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Investigation of fractured rock aquifer in South China using electrical resistivity tomography and self-potential methods

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Journal of Mountain Science 2019年第4期16卷 850-869页

作者： Muhammad HASAN shang Yan-jun JIN wei-jun Gulraiz AKHTER Key Laboratory of Shale Gas and Geoengineering Institute of Geology and Geophysics Chinese Academy of Sciences Institutions of Earth Science Chinese Academy of Sciences University of Chinese Academy of Sciences Department of Earth Sciences Quaid-i-Azam University

Assessment of fractured rock aquifers in many parts of the world is complicated given their strong heterogeneity. Delineation of the subsurface geological formation in the weathered terrain is essential for groundwater exploration. To achieve this goal, 2D electrical resistivity tomography(ERT) and self-potential(SP) in combination with joint profile method(JPM) and boreholes have been carried out to delineate the subsurface geological units, detect the fracture/fault zones in hard rock, monitor the groundwater flow, and estimate the groundwater reserves contained within the weathered terrain at a complex heterogeneous site of Huangbu, South Guangdong of China. The integration of resistivity images with the borehole lithology along three profiles delineates three subsurface distinct layers namely topsoil cover, weathered and unweathered layers. The incorporation of ERT and SP with JPM reveal five fractures/faults, i.e., F_1, F_2, F_3, F_4 and F_5. 2D ERT models interpret the less resistive anomalies as the fractures/faults zones, and high resistive anomalies as the fresh bedrock. The inversion program based on the smoothness-constraint is used on the resistivity field data to get more realistic three layered model. SP measurements are obtained along the same electrical profiles which provide the negative anomalies clearly indicating the groundwater preferential flow pathways along the fracture/fault zones. Hydraulic parameters namely hydraulic conductivity and transmissivity were determined to estimate the groundwater resources contained within the fractures/faults. The integrated results suggest that the fractures/faults zones are most appropriate places of drilling for groundwater exploration in the investigated area. Geophysical methods coupled with the upfront borehole data provides better understanding about the conceptual model of the subsurface geological formations. The current investigation demonstrates the importance of the integrated geophysical methods a

关键词： Electrical resistivity tomography Self-potential Groundwater flow Hard rock Heterogeneity Hydraulic parameters

Failure Mechanism and Material Requirements for Coal Lance in Blast Furnace

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Journal of Iron and Steel Research International 2012年第4期19卷 11-16页

作者： XIONG wei JIA Juan CHEN Jia-chao shang He-ming Key Laboratory for Ferrous Metallurgy and Resources Utilization of Ministry of Education Wuhan University of Science and Technology Wuhan 430081 Hubei China

Pulverized coal injection（PCI） is a key technology in modern ironmaking by blast furnace（BF） and the life of injection lance has a great influence on PCI operation and on normal running of blast *** is found that the main reasons for the failure of the lances are their outer surface oxidation and the inner surface erosion through monitoring some lances used in *** outer surface oxidation of the lances made of lCr18Ni9Ti is inevitable under high hot blast temperature condition through thermodynamics analysis.A mathematical model for calculating the temperature of common monocular coal lance had been developed according to the principles of mass and energy *** temperature and flow velocity of the hot blast would cause a rise in the lance *** influence of hot blast temperature is more *** lance temperature would decline when compressed air flux *** technology of dense phase pulverized coal is beneficial to extending lance’s life because decreasing solid-gas ratio would intensify erosion and burning *** anti-oxidation temperature of lance materials needs to be over 1000 ℃ for BF intensified *** order to increase the resistance to oxidation of the coal lance’s outer surface,oxidation-resistant steel or Al coating stainless steel is the appropriate material for BF *** the metal surface treatment technology to enhance the hardness of the coal lance’s internal surface could prolong the service life of coal lance

关键词： blast furnace coal lance failure mechanism material requirements

Two-parameters quasi-filled function algorithm for nonlinear integer programming

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第12期7卷 2083-2087页

作者： WANG wei-xiang shang You-lin ZHANG Lian-sheng Department of Mathematics Shanghai University Shanghai 200444 China Department of Applied Mathematics Tongji University Shanghai 200092 China Department of Mathematics Henan University of Science and Technology Luoyang 471003 China

A quasi-filled function for nonlinear integer programming problem is given in this paper. This function contains two parameters which are easily to be chosen. Theoretical properties of the proposed quasi-filled function are investigated. Moreover, we also propose a new solution algorithm using this quasi-filled function to solve nonlinear integer programming problem in this paper. The examples with 2 to 6 variables are tested and computational results indicated the efficiency and reliability of the pro- posed quasi-filled function algorithm.

关键词： Integer programming Local minimizer Global minimizer Filled function Global optimization

Two-dimensional functional materials:from properties to potential applications

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International Journal of Smart and Nano Materials 2020年第3期11卷 247-264页

作者： Yining wei Xiao Tang Jing shang Lin Ju Liangzhi Kou School of Mechanical Medical and Process EngineeringQueensland University of TechnologyBrisbaneAustralia School of Mechanical Medical and Process EngineeringQueensland University of TechnologyBrisbaneQLD 4001Australia

Two-dimensional(2D)materials have been extensively investigated since the exfoliation of *** to the excellent and versatile properties,the promising applications in novel nanodevices have been proposed in the last few ***,we chose three stable 2D materi-als which have been experimentally synthesized and have potential to be used for next-generation nanodevices,namely semiconducting MoS2,Janus MoSSe,and magnetic CrI_(3),to review their electronic/magnetic properties,and reveal the relationship of the propertiesapplications in *** showcase review on property-application is expected to provide new research insights into the investigations of 2D materials.

关键词： Two-dimensional functional materials

Federated learning-outcome prediction with multi-layer privacy protection

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Frontiers of Computer Science 2024年第6期18卷 186604页

作者： ZHANG Yupei LI Yuxin WANG Yifei wei Shuangshuang XU Yunan shang Xuequn School of Computer Science Northwestern Polytechnical University MIIT Lab of Big Data Storage and Management

Learning-outcome prediction (LOP) is a long-standing and critical problem in educational routes. Many studies have contributed to developing effective models while often suffering from data shortage and low generalization to various institutions due to the privacy-protection issue. To this end, this study proposes a distributed grade prediction model, dubbed FecMap, by exploiting the federated learning (FL) framework that preserves the private data of local clients and communicates with others through a global generalized model. FecMap considers local subspace learning (LSL), which explicitly learns the local features against the global features, and multi-layer privacy protection (MPP), which hierarchically protects the private features, including model-shareable features and not-allowably shared features, to achieve client-specific classifiers of high performance on LOP per institution. FecMap is then achieved in an iteration manner with all datasets distributed on clients by training a local neural network composed of a global part, a local part, and a classification head in clients and averaging the global parts from clients on the server. To evaluate the FecMap model, we collected three higher-educational datasets of student academic records from engineering majors. Experiment results manifest that FecMap benefits from the proposed LSL and MPP and achieves steady performance on the task of LOP, compared with the state-of-the-art models. This study makes a fresh attempt at the use of federated learning in the learning-analytical task, potentially paving the way to facilitating personalized education with privacy protection.

关键词： federated learning local subspace learning hierarchical privacy protection learning outcome prediction privacy-protected representation learning

States of Carbon Nanotube Supported Mo-Based HDS Catalysts

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Journal of Natural Gas Chemistry 2006年第3期15卷 203-210页

作者： Hongyan shang Chenguang Liu Yongqiang Xu Jieshan Qiu Fei wei Key Laboratory of Catalysis CNPC College of Chemistry and Chemical Engineering University of Petroleum Dongying 257061 China Carbon Research Laboratory Center for Nano Materials and Science Dalian University of Technology Dalian 116012 China Department of Chemical Engineering Tsinghua University Bejing 100085 China

The dispersion of the active phase and loading capacity of the Mo species on carbon nanotube （CNT） was studied by the XRD technique. The reducibility properties of Co-Mo catalysts in the oxide state over CNTs were investigated by TPR, while the sulfided Co-Mo/CNT catalysts were characterized by means of the XRD and LRS techniques. The activity and selectivity with respect to the hydrodesulfurization （HDS） performances on carbon nanotube supported Co-Mo catalysts were evaluated. It was found that the main active molybdenum species in the oxide state MoO3/CNT catalysts were MoO2, but not MoO3, as generally expected. The maximum loading before the formation of the bulk phase was lower than 6% （percent by mass, based on MoO3）. TPR studies revealed that the active species in the oxide state Co-Mo/CNT catalysts were reduced more easily at relatively lower temperatures in comparison to those of the Co-Mo/γ-Al2O3 catalysts, indicating that the CNT support promoted or favored the reduction of the active species. The active species of a Co-Mo-0.7/CNT catalyst were more easily reduced than those of the Co-Mo/CNT catalysts with Co/Mo atomic ratios of 0.2, 0.35, and 0.5, respectively, suggesting that the Co/Mo atomic ratio has a great effect on the reducibility of the active species. It was found that the incorporation of cobalt improved the dispersion of the molybdenum species on the support, and a phenomenon of mobilization and re-dispersion had occurred during the sulfurization process, resulting in low valence state Mo3S4 and Co-MoS2.17 active phases. HDS measurements showed that the Co-Mo/CNT catalysts were more active than the Co-Mo/γ-Al2O3 ones for the desulfurization of DBT, and the hydrogenolysis/hydrogenation selectivity of the Co-Mo/CNT catalysts was also much higher than those of the Co-Mo/γ-Al2O3. The Co-Mo/CNT catalyst with a Co/Mo atomic ratio of 0.7 showed the highest activity, whereas the catalyst with a Co/Mo atomic ratio of 0.35 had the highest selectivity.

关键词： carbon nanotubes XRD TPR HDS LRS

Accelerated design of lead-free high-performance piezoelectric ceramics with high accuracy via machine learning

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Journal of Advanced Ceramics 2023年第7期12卷 1389-1405页

作者： wei Gu Bin Yang Dengfeng Li Xunzhong shang Zhiyong Zhou Jinming Guo Key Laboratory of Green Preparation and Application for Functional Materials Ministry of EducationSchool of Materials Science and EngineeringHubei UniversityWuhan 430062China Key Laboratory of Inorganic Functional Materials and Devices Shanghai Institute of CeramicsChinese Academy of SciencesShanghai 201899China

The piezoelectric performance serves as the basis for the applications of piezoelectric *** ability to rapidly and accurately predict the piezoelectric coefficient(d_(33))is of much practical importance for exploring high-performance piezoelectric *** this work,a data-driven approach combining feature engineering,statistical learning,machine learning(ML),experimental design,and synthesis is trialed to investigate its accuracy in predicting d_(33) of potassium-sodium-niobate(K,Na)NbO_(3),KNN)-based *** atomic radius(AR),valence electron distance(DV)(Schubert),Martynov-Batsanov electronegativity(EN-MB),and absolute electronegativity(EN)are summarized as the four most representative features in describing d_(33) out of all 27 possible features for the piezoelectric *** four features contribute greatly to regression learning for predicting d_(33) and classification learning for distinguishing polymorphic phase boundary(PPB).The ML method developed in this work exhibits a high accuracy in predicting d_(33) of the piezoelectric *** example of KNN combined with 6 mo1%LiNbO_(3)demonstrates d_(33)3 of 184 pC/N,which is highly consistent with the predicted *** work proposes a novel feature-oriented guideline for accelerating the design of piezoelectric ceramic systems with large d_(33),which is expected to be widely used in other functional materials.

关键词： machine learning(ML) piezoelectric ceramics piezoelectric properties perovskite regression learning

Synthesis and characterization of biodegradable thermoplastic elastomers derived from N.N-bis （2-carboxyethyl）-pyromellitimide, poly（butylene succinate） and polyethylene glycol

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Frontiers of Chemical Science and Engineering 2018年第3期12卷 457-466页

作者： Jiaojiao shang Guo Yao Ronghui Guo wei Zheng Long Gu Jianwu Lan College of Light Industry and Textile and Food Engineering Sichuan University Chengdu 610065 China

Abstract Biodegradable poly（ether-imide-ester） elasto- mers were synthesized from succinic acid, 1,4-butanediol, polyethylene glycol 1000 and N＇,N-bis（2-carboxyethyl）- pyromellitimide which was derived from pyromellitic dianhydride and glycine. The chemical structures, crystal- linities, thermal stabilities, mechanical properties, hydro- philicities and biodegradabilities of these elastomers were investigated. The hard segments of the linear aliphatic poly （ether-ester） exhibited monoclinic chain packing. Increas- ing the amount of aromatic bisimide moieties in the poly （ether-ester） reduced the crystallinity of the material and improved the thermal stability and tensile strength of the elastomers. In addition, introducing a suitable amount of aromatic bisimide moieties into the poly（ether-ester） backbones endowed the elastomers with improved biode- gradability but too many aromatic bisimide groups reduced the biodegradability of the elastomers.

关键词： thermoplastic elastomers biodegradability thermo-stability mechanical property aromatic bisimide moiety

Simulative technology for auxiliary fuel tank separation in a wind tunnel

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Chinese Journal of Aeronautics 2016年第3期29卷 608-616页

作者： Ma Xin Liu wei Chen Ling Li Xiao Jia Zhenyuan shang Zhiliang Key Laboratory for Precision and Non-traditional Machining Technology of the Ministry of Education Dalian University of Technology

In this paper, we propose a simulative experimental system in wind tunnel conditions lbr the separation of auxiliary fuel tanks from an aircraft. The experimental system consists of a simulative release mechanism, a scaled model and a pose measuring system. A new release mechanism was designed to ensure stability of the separation. Scaled models of the auxiliary fuel tank were designed and their moment of inertia was adjusted by installing counterweights inside the model. Pose param- eters of the scaled model were measured and calculated by a binocular vision system. Additionally, in order to achieve high brightness and high signal-to-noise ratio of the images in the dark enclosed wind tunnel, a new high-speed image acquisition method based on miniature self-emitting units was pre- sented. Accuracy of the pose measurement system and repeatability of the separation mechanism were verified in the laboratory. Results show that the position precision of the pose measurement system can reach 0.1 mm, the precision of the pitch and yaw angles is less than 0.1° and that of the roll angle can be up to 0.3°. Besides, repeatability errors of models＂ velocity and angular velocity controlled by the release mechanism remain small, satisfying the measurement requirements. Finally, experiments for the separation of auxiliary fuel tanks were conducted in the laboratory.

关键词： Aircraft auxiliary equipmentBinocular vision Position and attitude mea-surement Release mechanism Simulation experiment