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Journal of Magnesium and Alloys 2019年第2期7卷 328-334页

作者： teng zhang School of Material Science and Engineering Xi’an University of Science and TechnologyXi’an 710054PR China

In order to utilize the carbon resource,a novel process was developed to extract magnesium from magnesia by the reaction between MgO-CaO-CaF_(2)and Al-C powders reinforced using mechanical activation technique under atmospheric pressure at 1223 K(950°C).The effects of C,CaO,CaF_(2),and ball milling time on the reduction ratio of magnesia was *** was found that the reduction ratio of magnesia is shown to increase with an increase of the variables being ***,the reactivity of Al was enhanced by the addition of C powder into reactants during the ball milling ***,the reduzate were characterized by X-ray diffraction(XRD),scanning electron microscopy(SEM)coupled with energy-dispersive X-ray spectroscopy(EDS)to reveal the reaction *** results indicated that the reaction mechanism was different from the previous report owing to the addition of C powder during high energy ball milling process,and the reaction process is the reduction of MgO,the formation of 12CaO7Al_(2)O_(3),MgAl_(2)O_(4)and CaAl_(1.9)O_(4)C_(0.4)when the content of CaO is 20-30 wt%,and when the content of CaO is more than 30 wt%,the MgAl_(2)O_(4)phase is ***,with the addition of CaF_(2),the reduction reaction is expressed as the reduction of MgO,the formation of 11CaO7Al_(2)O_(3)CaF_(2)and CaAl_(1.9)O_(4)C_(0.4).

关键词： Al-C powder Reduction reaction Ball milling Reaction mechanism

Multi-threaded code generation from Signal program to OpenMP

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Frontiers of Computer Science 2013年第5期7卷 617-626页

作者： Kai HU teng zhang Zhibin YANG State Key Laboratory of Software Development Environment Beihang University Beijing 100191 China School of Computer Science and Engineering Beihang University Beijing 100191 China IRIT-CNRS Universite de Toulouse Toulouse 31062 France

The use of multi-core processors will become a trend in safety critical systems. For safe execution of multi- threaded code, automatic code generation from formal spec- ification is a desirable method. Signal, a synchronous lan- guage dedicated for the functional description of safety crit- ical systems, provides soundness semantics for determinis- tic concurrency. Although sequential code generation of Sig- nal has been implemented in Polychrony compiler, deter- ministic multi-threaded code generation strategy is still far from mature. Moreover, existing code generation methods use certain multi-thread library, which limits the cross plat- form executions. OpenMP is an application program inter- face （API） standard for parallel programming, supported by several mainstream compilers from different platforms. This paper presents a methodology translating Signal program to OpenMP-based multi-threaded C code. First, the intermedi- ate representation of the core syntax of Signal using syn- chronous guarded actions is defined. Then, according to the compositional semantics of Signal equations, the Signal pro- gram is synthesized to dependency graph （DG）. After par- allel tasks are extracted from dependency graph, the Signal program can be finally translated into OpenMP-based C code which can be executed on multiple platforms.

关键词： multi-thread synchronous language Signal,code generation OpenMP

Corrosion and aging of organic aviation coatings:A review

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Chinese Journal of Aeronautics 2023年第4期36卷 1-35页

作者： Tianyu zhang teng zhang Yuting HE Yuchen WANG Yaping BI Air Force Engineering University Xi’an 710038China

Organic anticorrosive aviation coatings are an effective guarantee for aviation structure,since aircraft corrosion can lead to great economic *** it is during ground parking or air cruises,organic aviation coatings are important barriers to the corrosion of aviation *** the vigorous development of the aviation industry,organic aviation coatings continue to meet the challenges of diverse,complex,and harsh service *** review analyzes and summarizes the research status of the types and development of organic aviation coatings,influencing factors and mechanisms,experimental methods,calendar life research methods,and modification *** also summarizes the research results that have been achieved to *** current research deficiencies in the equivalence relationship between atmospheric exposure and artificial acceleration,failure criteria and life prediction were pointed out,and nano-modification technology,and future research strategies and directions that need breakthroughs are discussed.

关键词： Aging Calendar life Classification Corrosion Experimental methods Modification Organic aviation coatings

Distributed Source-Load-Storage Cooperative Low-Carbon Scheduling Strategy Considering Vehicle-to-Grid Aggregators

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Journal of Modern Power Systems and Clean Energy 2024年第2期12卷 440-453页

作者： Xiao Xu Ziwen Qiu teng zhang Hui Gao School of Automation Nanjing University of Posts and TelecommunicationsNanjing210023China

The vehicle-to-grid(V2G)technology enables the bidirectional power flow between electric vehicle(EV)batteries and the power grid,making EV-based mobile energy storage an appealing supplement to stationary energy storage ***,the stochastic and volatile charging behaviors pose a challenge for EV fleets to engage directly in multi-agent *** unlock the scheduling potential of EVs,this paper proposes a source-load-storage cooperative low-carbon scheduling strategy considering V2G *** uncertainty of EV charging patterns is managed through a rolling-horizon control framework,where the scheduling and control horizons are adaptively adjusted according to the availability periods of ***,a Minkowski-sum based aggregation method is employed to evaluate the scheduling potential of aggregated EV fleets within a given scheduling *** method effectively reduces the variable dimension while preserving the charging and discharging constraints of individual ***,a Nash bargaining based cooperative scheduling model involving a distribution system operator(DSO),an EV aggregator(EVA),and a load aggregator(LA)is established to maximize the social welfare and improve the low-carbon performance of the *** model is solved by the alternating direction method of multipliers(ADMM)algorithm in a distributed manner,with privacy of participants fully *** proposed strategy is proven to achieve the objective of low-carbon economic operation.

关键词： Electric vehicle(EV) low-carbon scheduling mobile storage system Nash bargaining power flexibility alternating direction method of multipliers(ADMM).

An efficient parallel algorithm of variational nodal method for heterogeneous neutron transport problems

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Nuclear Science and Techniques 2024年第4期35卷 29-45页

作者： Han Yin Xiao-Jing Liu teng-Fei zhang School of Nuclear Science and Engineering Shanghai Jiao Tong UniversityShanghai 2002040China

The heterogeneous variational nodal method(HVNM)has emerged as a potential approach for solving high-fidelity neutron transport ***,achieving accurate results with HVNM in large-scale problems using high-fidelity models has been challenging due to the prohibitive computational *** paper presents an efficient parallel algorithm tailored for HVNM based on the Message Passing Interface *** algorithm evenly distributes the response matrix sets among processors during the matrix formation process,thus enabling independent construction without *** the formation tasks are completed,a collective operation merges and shares the matrix sets among the *** the solution process,the problem domain is decomposed into subdomains assigned to specific processors,and the red-black Gauss-Seidel iteration is employed within each subdomain to solve the response matrix ***-to-point communication is conducted between adjacent subdomains to exchange data along the *** accuracy and efficiency of the parallel algorithm are verified using the KAIST and JRR-3 test *** results obtained with multiple processors agree well with those obtained from Monte Carlo *** parallelization of HVNM results in eigenvalue errors of 31 pcm/-90 pcm and fission rate RMS errors of 1.22%/0.66%,respectively,for the 3D KAIST problem and the 3D JRR-3 *** addition,the parallel algorithm significantly reduces computation time,with an efficiency of 68.51% using 36 processors in the KAIST problem and 77.14% using 144 processors in the JRR-3 problem.

关键词： Neutron transport Variational nodal method Parallelization KAIST JRR-3

Numerical Analysis of Static Performance Comparison of Friction Stir Welded versus Riveted 2024-T3 Aluminum Alloy Stiffened Panels

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Chinese Journal of Mechanical Engineering 2014年第4期27卷 761-767页

作者： SHAO Qing HE Yuting zhang teng WU Liming Aeronautics and Astronautics Engineering College Air Force Engineering University

Most researches on the static performance of stiffened panel joined by friction stir welding（FSW） mainly focus on the compression stability rather than shear stability. To evaluate the potential of FSW as a replacement for traditional rivet fastening for stiffened panel assembly in aviation application, finite element method（FEM） is applied to compare compression and shear stability performances of FSW stiffened panels with stability performances of riveted stiffened panels. FEMs of 2024-T3 aluminum alloy FSW and riveted stiffened panels are developed and nonlinear static analysis method is applied to obtain buckling pattern, buckling load and load carrying capability of each panel model. The accuracy of each FEM of FSW stiffened panel is evaluated by stability experiment of FSW stiffened panel specimens with identical geometry and boundary condition and the accuracy of each FEM of riveted stiffened panel is evaluated by semi-empirical calculation formulas. It is found that FEMs without considering weld-induced initial imperfections notably overestimate the static strengths of FSW stiffened panels. FEM results show that, buckling patterns of both FSW and riveted compression stiffened panels represent local buckling of plate between stiffeners. The initial buckling waves of FSW stiffened panel emerge uniformly in each plate between stiffeners while those of riveted panel mainly emerge in the mid-plate. Buckling patterns of both FSW and riveted shear stiffened panels represent local buckling of plate close to the loading corner. FEM results indicate that, shear buckling of FSW stiffened panel is less sensitive to the initial imperfections than compression buckling. Load carrying capability of FSW stiffened panel is less sensitive to the initial imperfections than initial buckling. It can be concluded that buckling loads of FSW panels are a bit lower than those of riveted panels whereas carrying capabilities of FSW panels are almost equivalent to those of riveted panel

关键词： friction stir welding rivet fastening stiffened panel stability performance finite element method(FEM)

Kinetic study on the reaction between CO_2-CO and wustite using the isotope exchange method

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International Journal of Minerals,Metallurgy and Materials 2013年第2期20卷 125-130页

作者： teng zhang Xiao-jun Hu Kuo-Chih Chou State Key Laboratory of Advanced Metallurgy University of Science and Technology Beijing School of Metallurgical and Ecological Engineering University of Science and Technology Beijing

To investigate the reaction between CO2-CO and wustite using the isotope exchange method at 1073, 1173, 1273, and 1373 K, the experiment apparatus was designed to simulate the fluidized bed. The chemical rate constant was estimated by considering the effect of gas phase mass transfer on the reaction. It is found that the chemical rate constant is inversely decreased with the increase in the ratio of CO2/CO by volume. The activation energy of reaction is in a linear relationship with the ratio of COs/CO by volume, and the average activation energy is 155.37 kJ/mol.

关键词： kinetics isotope exchange rate constants wustite activation energy

Integration of traditional Chinese medicine and Western medicine in the era of precision medicine

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Journal of Integrative Medicine 2017年第1期15卷 1-7页

作者： Wen-jian Wang teng zhang Institute of Integrative Medicine Huashan Hospital Fudan University Clinical Research Institute of Chinese Integrative Medicine Shanghai Academy of Traditional Chinese Medicine Yueyang Hospital of Chinese Integrative Medicine Shanghai University of Traditional Chinese Medicine

Precision medicine has received growing recognition from clinicians, health systems, and the pharmaceutica industry, as well as patients and policymakers, which will leave a major impact on the practice of medicine. Interestingly, traditional Chinese medicine （TCM） provides personalized medical treatment based on the theory of TCM characterized by holistic concept and pattem differentiation. This, to some extent, is similar to the personalized medical treatment of precision medicine. In China, TCM as well as Western medicine （WM） plays an important role in healthcare. In this article, the authors summarized the influence of precision medicine on current medical directions, the advantages of TCM in disease treatment, further development of precision medicine and the strategies for integration of TCM and WM under this new treatment approach. In addition, the authors discuss the perspective of precise medical diagnosis and treatment, precise prevention, and the complementary advantages of the integration of TCM and WM. Finally, the authors give their perspectives on the challenges and opportunities presented by precision medicine, in the context of further research toward the integration of TCM and WM.

关键词： precision medicine medicine, Chinese traditional Western medicine integrative medicine

Individual identification using multi-metric of DTI in Alzheimer's disease and mild cognitive impairment

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Chinese Physics B 2018年第8期27卷 655-664页

作者： Ying-teng zhang Shen-Quan Liu School of Mathematics South China University of TechnologyGuangzhou 510640China

Accurate identification of Alzheimer＇s disease （AD） and mild cognitive impairment （MCI） is crucial so as to improve diagnosis techniques and to better understand the neurodegenerative process. In this work, we aim to apply the machine learning method to individual identification and identify the discriminate features associated with AD and MCI. Diffusion tensor imaging scans of 48 patients with AD, 39 patients with late MCI, 75 patients with early MCI, and 51 age-matched healthy controls （HCs） are acquired from the Alzheimer＇s Disease Neuroimaging Initiative database. In addition to the common fractional anisotropy, mean diffusivity, axial diffusivity, and radial diffusivity metrics, there are two novel metrics, named local diffusion homogeneity that used Spearman＇s rank correlation coefficient and Kendall＇s coefficient concordance, which are taken as classification metrics. The recursive feature elimination method for support vector machine （SVM） and logistic regression （LR） combined with leave-one-out cross validation are applied to determine the optimal feature dimensions. Then the SVM and LR methods perform the classification process and compare the classification performance. The results show that not only can the multi-type combined metrics obtain higher accuracy than the single metric, but also the SVM classifier with multi-type combined metrics has better classification performance than the LR classifier. Statistically, the average accuracy of the combined metric is more than 92% for all between-group comparisons of SVM classifier. In addition to the high recognition rate, significant differences are found in the statistical analysis of cognitive scores between groups. We further execute the permutation test, receiver operating characteristic curves, and area under the curve to validate the robustness of the classifiers, and indicate that the SVM classifier is more stable and efficient than the LR classifier. Finally, the uncinated fasciculus, cingulum, corp

关键词： Alzheimer's disease mild cognitive impairment, diffusion tensor imaging classification

Soil detachment and transport under the combined action of rainfall and runoff energy on shallow overland flow

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Journal of Mountain Science 2017年第7期14卷 1373-1383页

作者： LI Guang-lu ZHENG teng-hui FU Yu LI Bai-qiao zhang teng College of Resource and Environment Northwest A & F University Key laboratory for Agricultural Resources and Environmental Rehabilitation on the Loess Plateau of Agriculture Ministry of China

Rainfall and runoff energy results in soil erosion. This paper presents new the concepts of rainfall and runoff energy and analyzes the relationship of rainfall energy and runoff energy with sediment transport based on the conversion theory of kinetic and potential energy using artificial rainfall and mechanical calculation. The results show that the ratio of sediment detachment in sloping fallow overland flow increases with the slope gradient,rainfall energy and runoff energy, while the sediment detachment ratio under raindrop impact are significantly higher than those under no raindrop impact. The sediment concentration increases with the slope gradient and rainfall energy; when the slope gradient and rainfall energy are constant, the sediment concentration decreases as the runoff energy increases. Rainfall disturbance coefficients have a logarithmic correlation with the rate of rainfall energy and runoff energy. On the same slope gradient,when the rainfall energy is constant, the disturbance coefficient decreases as the runoff energy increases,while when the runoff energy is constant, the disturbance coefficient increases as the rainfall energyincreases. Rainfall energy results in sediment detachment, and runoff energy is the transportation for erosion sediment. This showed that rainfall energy and runoff energy are important in the sediment detachment and transportation of shallow overland flow.

关键词： Shallow overland flow Rainfall energy Runoff energy Sediment detachment Disturbancecoefficient