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User Purchase Intention Prediction Based on Improved deep Forest

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Computer Modeling in Engineering & Sciences 2024年第4期139卷 661-677页

作者： Yifan zhang Qiancheng Yu Lisi zhang School of Computer Science and Engineering North Minzu UniversityYinchuan750030China Laboratory of Graphics and Images of the State Ethnic Affairs Commission North Minzu UniversityYinchuan750030China

Widely used deep neural networks currently face limitations in achieving optimal performance for purchase intention prediction due to constraints on data volume and hyperparameter *** address this issue,based on the deep forest algorithm and further integrating evolutionary ensemble learning methods,this paper proposes a novel deep Adaptive Evolutionary Ensemble(dAEE)*** model introduces model diversity into the cascade layer,allowing it to adaptively adjust its structure to accommodate complex and evolving purchasing behavior ***,this paper optimizes the methods of obtaining feature vectors,enhancement vectors,and prediction results within the deep forest algorithm to enhance the model’s predictive *** demonstrate that the improved deep forest model not only possesses higher robustness but also shows an increase of 5.02%in AUC value compared to the baseline ***,its training runtime speed is 6 times faster than that of deep models,and compared to other improved models,its accuracy has been enhanced by 0.9%.

关键词： Purchase prediction deep forest differential evolution algorithm evolutionary ensemble learning model selection

Seasonal thermal energy storage using natural structures:GIS-based potential assessment for northern China

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Building Simulation 2024年第4期17卷 561-574页

作者： Yichi zhang Jianjun Xia Midea HVAC Heating&Ventilation Equipment Co. LtdFoshan528311China Building Energy Research Center Tsinghua UniversityBeijing100084China

Seasonal thermal energy storage(StES)allows storing heat for long-term and thus promotes the shifting of waste heat resources from summer to winter to decarbonize the district heating(dH)*** being a promising solution for sustainable energy system,large-scale StES for urban regions is lacking due to the relatively high initial investment and extensive land *** close the gap,this study assesses the potentials of using two naturally available structures for StES,namely valley and ground pit *** on geographical information system(GIS)methods,the available locations are searched from digital elevation model and selected considering several criteria from land uses and construction *** costs of dams to impound the reservoir and the yielded storage capacities are then quantified to guide the choice of suitable *** assessment is conducted for the northern China where dH systems and significant seasonal differences of energy demand *** total,2,273 valley sites and 75 ground pit sites are finally identified with the energy storage capacity of 15.2 billion GJ,which is much larger than the existing dH demand in northern *** results also prove that 682 valley sites can be achieved with a dam cost lower than 20 CNY/m^(3).By conducting sensitivity analysis on the design dam wall height and elevations,the choices of available natural structures are expanded but practical issues about water pressures and constructions are also ***,the identified sites are geographically mapped with nearest urban regions to reveal their roles in the dH *** general,560 urban regions are found with potential StES units and most of them have StES storage capacities larger than their own dH *** novel planning methodology of this study and publicly available datasets create possibilities for the implementations of large-scale StES in urban dH systems.

关键词： seasonal thermal energy storage geographical information system district heating water reservoir

Enhanced charge separation by incomplete calcination modified co-doped tiO_(2)nanoparticle for isothiazolinone photocatalytic degradation

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Nano Research 2024年第6期17卷 4834-4843页

作者： Zhiren Guo Xiao zhang Xinyuan Li Chang Cui Zilei zhang Hansheng Li dongxiang zhang Jinying Li Xiyan Xu Jiatao zhang School of Chemistry and Chemical Engineering Beijing Institute of TechnologyBeijing 102488China department of Chemistry MSU-BIT UniversityShenzhen 517182Chin

Photocatalytic oxidation techniques are promising for degradation of the highly ecotoxic and refractory isothiazolinone bactericides in relevant industrial ***,low charge separation and directional transport efficiency under solar light radiation restrain their practical ***,we report a nanostructured photocatalyst doped with Gd and B in tiO_(2)with carbon incorporation and defect formation through incomplete *** specific surface area,grain size,and hydrophilicity of tiO_(2)are improved,which is beneficial for the interfacial reaction between the photocatalyst and *** reduction of the bandgap,the broadening of the photo-absorption range,and the retarded electron-hole recombination promote the photocatalytic performance due to the improved oxygen vacancies based on the electron distribution *** difference in partial density of states(ΔPdOS)between the current catalyst and raw tiO_(2)indicates that the co-doping of Gd and B with incomplete calcination changes the electronic hybridization of conduction band and valence band near the Fermi level,and affects the band gap *** improved charge separation and directional transport efficiency and benefited the formation of main active species,including•OH and O_(2)•−,for the pollutant *** rate of photocatalytic removal of benzisothiazolinone(BIt)by the current photocatalyst reaches 1.25 h^(−1),being 4.31 times that of tiO_(2).the current work offers a constructive approach to the design and synthesis of nanostructured photocatalysts for the photocatalytic degradation of refractory organic pollutants.

关键词： tiO_(2)nanoparticle charge separation oxygen vacancies electron distribution modification photocatalytic degradation

tHE SUPERCLOSENESS OF tHE FINItE ELEMENt MEtHOd FOR A SINGULARLY PERtURBEd CONVECtION-dIFFUSION PROBLEM ON A BAKHVALOV-tYPE MESH IN 2d

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Acta Mathematica Scientia 2024年第4期44卷 1572-1593页

作者： Chunxiao zhang Jin zhang School of Mathematics and Statistics Shandong Normal UniversityJinan 250014China

For singularly perturbed convection-diffusion problems,supercloseness analysis of the finite element method is still open on Bakhvalov-type meshes,especially in the case of *** difficulties arise from the width of the mesh in the layer adjacent to the transition point,resulting in a suboptimal estimate for *** analysis techniques cannot handle these difficulties *** fill this gap,here a novel interpolation is designed delicately for the smooth part of the solution,bringing about the optimal supercloseness result of almost order 2 under an energy norm for the finite element *** theoretical result is uniform in the singular perturbation parameterεand is supported by the numerical experiments.

关键词： singularly perturbed convection-diffusion finite element method supercloseness Bakhvalov-type mesh

Stabilization Controller of An Extended Chained Nonholonomic System With disturbance:An FAS Approach

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IEEE/CAA Journal of Automatica Sinica 2024年第5期11卷 1262-1273页

作者： Zhongcai zhang Guangren duan School of Engineering Qufu Normal UniversityRizhao 276826China Center for Control Science and technology Southern University of Science and TechnologyShenzhen 518055 Center for Control theory and Guidance technology Harbin Institute of TechnologyHarbin 150001China

this study examines the stabilization issue of extended chained nonholonomic systems(ECNSs)with external *** the existing approaches,we transform the considered system into a fully actuated system(FAS)model,simplifying the stabilizing controller *** implement a separate controller design and propose exponential stabilization controller and finite-time stabilization controller under finite-time disturbance observer(FtdO)for the two system *** addition,we discuss the specifics of global stabilization control *** approach demonstrates that two system states exponentially or asymptotically converge to zero under the provided switching stabilization control strategy,while all other system states converge to zero within a finite time.

关键词： design stabilization system

Preface:Special issue on soil ecology and sustainability for celebrating the 70th anniversary of ISSCAS

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Pedosphere 2024年第1期34卷 1-2页

作者： Fusuo zhang China Agricultural University Beijing 100193China

the Institute of Soil Science, Chinese Academy of Sciences (ISSAS) was founded in 1953. the institute aims to solve the problems of agricultural development, ecological conservation, and environmental protection and to promote the development of soil ***’s arable land is facing dual pressure of construction occupation and ecological degradation. this is because the rapid urbanization and industrialization continue to occupy high-quality arable land and the quality of complementary arable land is relatively low (Cumming et al., 2014;Wang S t et al., 2021). to ensure national food security, agricultural product quality, and agricultural ecology security,it is particularly important to ensure soil health to maintain sustainable agricultural production.

关键词： soil occupation maintain

Electronic origin of structural degradation in Li-rich transition metal oxides:the case of Li_(2)MnO_(3)and Li_(2)RuO_(3)

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Journal of Semiconductors 2024年第4期45卷 82-86页

作者： Peng zhang Key Laboratory of Optoelectronic devices and Systems of Ministry of Education and Guangdong Province College of Physics andOp toelec-tronic EngineeringShenzhen UniversityShenzhen 518060China

Li_(2)MnO_(3)and Li_(2)RuO_(3)represent two prototype Li-rich transition metal(tM)oxides as high-capacity cathodes for Li-ion batteries,which have similar crystal structures but show quite different cycling ***,based on the first-princi-ples calculations,we systematically studied the electronic structures and defect properties of these two Li-rich cathodes,in order to get more understanding on the structural degradation mechanism in Li-rich tM *** calculations indicated that the structural and cycling stability of Li_(2)MnO_(3)and Li_(2)RuO_(3)depend closely on their electronic structures,especially the energy of their highest occupied electronic states(HOS),as it largely determines the defect properties of these *** Li_(2)MnO_(3)with low-energy HOS,we found that,due to the defect charge transfer mechanism,various defects can form spontaneously in its host structure as Li ions are extracted upon delithiation,which seriously deteriorates its structural and cycling *** for Li_(2)RuO_(3),on the other hand,we identified that the high-energy HOS prevents it from the defect formation upon delithi-ation and thus preserve its cycling *** studies thus illustrated an electronic origin of the structural degradation in Li-rich tM oxides and implied that it is possible to improve their cycling performances by carefully adjusting their tM compo-nents.

关键词： defects Li-ion batteries first-principles calculations

Near-surface wind field characteristics of the desert-oasis transition zone in dunhuang,China

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Journal of Arid Land 2024年第5期16卷 654-667页

作者： PAN Jiapeng zhang Kecun AN Zhishan zhang Yu Key Laboratory of desert and desertification&dunhuang Gobi and desert Ecology and Environment Research Station Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China University of Chinese Academy of Sciences Beijing 100049China

the desert-oasis transition zone(dOtZ)serves as a buffer area between the desert and *** its wind field characteristics is of great significance for the prevention and control of aeolian disasters in the *** this study,we used meteorological data during 2013–2019 from the portable meteorological stations at five sites(site A on the edge of the oasis,sites B,C,and d in the dOtZ,and site O in the desert)in dunhuang,China to analyze the near-surface wind field characteristics and their causes,as well as to reveal the key role of the dOtZ in oasis *** results showed that the mean wind speed,frequency of sand-driving wind,and directional variability of wind decreased from west to east within the dOtZ,and wind speed was significantly affected by air *** terrain influenced the prevailing winds in the region,mainly from northeast and *** some areas adjacent to the oasis were controlled by southeasterly *** indicated that the near-surface wind field characteristics of the dOtZ were caused by the combined effects of local terrain and surface hydrothermal *** site d,the annual drift potential(dP)was 24.95 vector units(VU),indicating a low wind energy environment,and the resultant drift direction(Rdd)showed obvious seasonal ***,the dOtZ played an important buffering role between the desert and *** with the desert,the mean wind speed in the oasis decreased by 64.98%,and the prevailing wind direction was more *** results of this study will be useful in interpreting the aeolian activity of the dOtZ in dunhuang.

关键词： desert-oasis transition zone near-surface wind field hydrothermal difference sand-driving wind aeolian environment dunhuang

toughening additive manufactured Zr-based bulk metallic glass composites by martensite phase transformation

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Journal of Materials Science & technology 2024年第3期170卷 95-102页

作者： Pengcheng zhang Cheng zhang Jie Pan di Ouyang Lin Liu State Key Laboratory of Materials Processing and die&Mould technology School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074China

Additive manufacturing technology based on laser powder bed fusion(LPBF)offers a novel approach for fabricating bulk metallic glass(BMG)products without restriction in size and ***,the BMGs prepared by LPBF usually suffered from less plasticity and poorer fracture toughness as compared to their cast counterparts due to partial crystallization in heat-affected zones(HAZs).Since crystallization in HAZs is hard to avoid completely in LPBF BMGs,it is desirable to design a suitable alloy system,in which only ductile crystalline phase,instead of brittle intermetallics,is formed in *** unique structure could effectively increase the toughness/plasticity of the LPBF *** achieve this goal,a quaternary BMG system with a composition of Zr_(47.5)Cu_(45.5)Al_(5)Co_(2)is adopted and subjected to *** is found that nearly a single phase of B_(2)-ZrCu is precipitated in HAZs,while a fully amorphous phase is formed in molten pools(MPs).this B_(2)phase reinforced BMG composite exhibits excellent mechanical properties with enhanced plasticity and ***,it is easy to modulate the mechanical properties by altering the amount of the B_(2)phase via adjusting the laser energy ***,the best combination of strength,plasticity,and notch toughness is obtained in the BMG composite containing 27.4%B_(2)phase and 72.6%amorphous phase,which exhibits yield strength(σ_(s))of 1423 MPa,plastic strain(ε_(p))of 4.65%,and notch toughness(K_(q))of 53.9 MPa m 1/***,a notable strain-hardening is also *** improvement of plasticity/toughness and appearance of strain-hardening behavior are mainly due to the martensite phase transformation from the B_(2)phase to the Cm phase during plastic deformation(i.e.,the phase transformation-induced plasticity effect).the current work provides a guide for making advanced BMGs and BMG composites by additive manufacturing.

关键词： Laser powder bed fusion Bulk metallic glass composites Phase transformation-induced plasticity deformation mechanism