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Hybrid partial least squares and neural network approach for short-term electrical load forecasting

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控制理论与应用（英文版） 2008年第1期6卷 93-96页

作者： Shukang yang ming LU Huifeng xue College of Automation Northwestern Polytechnical University Xi＇an Shanxi 710072 China

Intelligent systems and methods such as the neural network （NN） are usually used in electric power systems for short-term electrical load forecasting. However, a vast amount of electrical load data is often redundant, and linearly or nonlinearly correlated with each other. Highly correlated input data can result in erroneous prediction results given out by an NN model. Besides this, the determination of the topological structure of an NN model has always been a problem for designers. This paper presents a new artificial intelligence hybrid procedure for next day electric load forecasting based on partial least squares （PLS） and NN. PLS is used for the compression of data input space, and helps to determine the structure of the NN model. The hybrid PLS-NN model can be used to predict hourly electric load on weekdays and weekends. The advantage of this methodology is that the hybrid model can provide faster convergence and more precise prediction results in comparison with abductive networks algorithm. Extensive testing on the electrical load data of the Puget power utility in the USA confirms the validity of the proposed approach.

关键词： Electric loads Forecasting Hybrid neural networks model

Interfacial intermetallic compound growth and shear strength of low-silver SnAgCuBiNi/Cu lead-free solder joints

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International Journal of Minerals,Metallurgy and Materials 2013年第9期20卷 883-889页

作者： Guo-qiang Wei Lei Wang Xin-qiang Peng ming-yang xue School of Mechanical and Automotive Engineering South China University of Technology

The growth rule of the interfacial intermetallic compound （IMC） and the degradation of shear strength of ***-0.5Cu-2.0Bi-0.05Ni （SACBN）/Cu solder joints were investigated in comparison with Sn-3.0Ag-0.5Cu （SAC305）/ Cu solder joints aging at 373, 403, and 438 K. The results show that （Cul-x,Nix）6Sn5 phase forms between the SACBN solder and Cu substrate during soldering. The interracial IMC thickens constantly with the aging time increasing, and the higher the aging temperature, the faster the IMC layer grows. Compared with the SAC305/Cu couple, the SACBN/Cu couple exhibits a lower layer growth coefficient. The activation energies of IMC growth for SACBN/Cu and SAC305/Cu couples are 111.70 and 82.35 kJ/mol, respectively. In general, the shear strength of aged solder joints declines continuously. However, SACBN/Cu solder joints exhibit a better shear strength than SAC305/Cu solder joints.

关键词： soldering alloys soldered joints aging intermetallics activation energy shear strength

Synthesis, Structures, Fluorescence and Magnetism of Two Lanthanide Metal-organic Frameworks with CaF2 Topology Based on Silicon-centered Tetrahedral Ligand

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Chemical Research in Chinese Universities 2013年第4期29卷 611-616页

作者： LI yang-xue xue ming HUANG Lin CHEN Si-ru QIU Shi-lun State Key Laboratory of Inorganic Synthesis and Preparative Chemistry Jilin University Changchun 130012 P. R. China

Two 3D multifunctional lanthanide metal-organic frameworks（MOFs）, Pr（HTCPS）（H20）·2DMF·C2H2OH·5H2O（JUC-93） and Pr3（TCPS）2（NO3）（H2O）4（DMA）2.2DMA.C2H5OH.3H2O（JUC-94）[H4TCPS=tetrakis（4-carboxyphenyl）- silane, DMF=N,N＇-dimethylformamide, DMA=N,N＇-dimethylacetamide and JUC=Jilin University China] were synthe- sized by the self-assembly of a rigid silicon-centered tetrahedral carboxylate ligand H4TCPS and Pr（III） ions in different solvothermal reactions. X-Ray crystallography revealed that they exhibited a rare CaFE topology framework, constructed from the 4-connected tetrahedral TCPS unit with the 8-connected dinuclear praseodymium cluster unit and trinuclear praseodymium cluster unit, respectively. In addition, the luminescent and magnetic properties of the two compounds were investigated.

关键词： Metal-organic framework Tetrakis(4-carboxyphenyl)silane CaF2 topology Magnetic property Fluores- cence

Using ^(137)Cs Tracer Technique to Evaluate Erosion and Deposition of Black Soil in Northeast China

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Pedosphere 2006年第2期16卷 201-209页

作者： FANG Hua-Jun yang xue-ming ZHANG Xiao-Ping LIANG Ai-Zhen Northeast Institute of Geography and Agricultural Ecology CAS Changchun 130012 （China）. Graduate School of the Chinese Academy of Sciences Beijing 100039 （China） Greenhouse ＆ Processing Crops Research Centre Agriculture ＆ Agri-Food Canada Harrow Ontario NOR 1 GO （Canada）

Soil and water losses through erosion have been serious in the black soil region of Northeast China. Therefore, a sloping cultivated land in Songnen Plain was selected as a case study to： 1） determine the ^137Cs reference inventory in the study area; 2） calculate erosion and deposition rates of black soil on different slope locations; 3） conduct a sensitivity analysis of some model parameters; and 4） compare overall outputs using four different models. Three transects were set in the field with five slope locations for each transect, including summit, shoulder-slope, back-slope, foot-slope, and toe-slope. Field measurements and model simulation were used to estimate a bomb-derived ^137Cs reference inventory in the study area. Soil erosion and deposition rates were estimated using four ^137Cs models and percentage of ^137Cs loss/gain. The ^137Cs reference value in the study area was 2 232.8 Bq m^-2 with ^137Cs showing a clear topographic pattern, decreasing from the summit to shoulder-slope, then increasing again at the foot-slope and reaching a maximum at the toe-slope, Predicted soil redistribution rates for different slope locations varied. Among models, the yang Model （yang-M） overestimated erosion loss but underestimated deposition. However, the standard mass balance model （MBM1） gave predictions similar to a mass balance model incorporating soil movement by tillage （MBM2）. Sensitivity analysis of the proportion factor and distribution pattern of ^137Cs in the surface layer demonstrated the impact of ^137Cs enrichment on calculation of the soil erosion rate. Factors influencing the redistribution of fallout ^137Cs in landscape should be fully considered as calculating soil redistribution rate using ^137Cs technique.

关键词： black soil cesium-137 (^137Cs) Northeast China quantitative models soil erosion

Syntheses, Structures, Fluorescence and Magnetism of Six Lanthanide Metal-organic Frameworks Based on Silicon-centered Tetrahedral Ligand

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Chemical Research in Chinese Universities 2013年第2期29卷 196-200页

作者： LI yang-xue xue ming GUO Li-jia HUANG Lin CHEN Si-ru QIU Shi-lun State Key Laboratory of Inorganic Synthesis and Preparative Chemistry Jilin University Changchun 130012 P. R. China

Multifunctional lanthanide metal-organic frameworks（MOFs）, M（H4TCPS）（H20）l.5[M=Tb（JUC-95a）, Er（JUC-95b）, Dy（JUC-95c）, Tm（JUC-95d）, Y（JUC-95e） and Pr（JUC-95f）; H4TCPS=tetrakis（4-carboxyphenyl）silane] were synthesized via the reaction of the lanthanide metal ions（Ln3） with a rigid silicon-centered tetrahedral carbo- xylate ligand H4TCPS via a hydrothermal synthesis method. X-Ray diffraction（XRD） analyses reveal that they are extremely similar in structure and crystallized in a monoclinic system with space group C2/c. Two eight-coordinated metal centers and four tetrahedral H4TCPS groups constructed a paddle-wheel building block. The paddle-wheel buil- ding blocks assembled with each other via one oxygen bridge from a water molecule to lead to a 1D infinite inorganic rod-shaped chain, --Y--O--C--O--Y--, along the [001] direction. These 1D inorganic rod-shaped chains linked with the phenyl groups of the tetrahedral HaTCPS ligand to form a 3D framework. In addition, the luminescent and magnetic properties of these compounds show that they could be potential antiferromagnetic and fluorescent mate- rials.

关键词： Metal-organic framework Tetrakis(4-carboxyphenyl)silane Magnetic property Fluorescence

Interplay between Microscopic Structures and Macroscopic Viscoelastic Properties of Polyampholyte Gels

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Chinese Journal of Polymer Science 2024年第9期42卷 1360-1367,I0008页

作者： You-Cai xue Yi-ming yang Di Jia Beijing National Laboratory for Molecular Sciences Laboratory of Polymer Physics and ChemistryInstitute of ChemistryChinese Academy of SciencesBeijing100190China University of Chinese Academy of Sciences Beijing100049China

Polyampholyte gels,which have hierarchical structures,exhibit excellent self-healing properties and have great promise for biomaterials and *** investigated the relationship between microscopic structures and macroscopic viscoelastic properties of polyampholyte gels and found three factors influencing their viscoelastic properties,including the chemical crosslinking bonds,topological entanglements controlled by monomer concentration,and the ionic *** strength plays a major role on the strength of ionic bonds.A crossover point of elastic modulus and loss modulus was observed in the dynamic frequency sweeps at low monomer concentration or low chemical crosslinking density for gels with intermediate strength of ionic *** solid-liquid transition signaled by the crossover point is a typical feature of dynamic associated gels,representing the dynamical association-dissociation of the ionic bonds and full relaxation of the topological entanglements in the gel *** the crossover point disappears when the ionic bonds are too weak or too strong to form“permanent”***,in the non-linear yielding measurement,gels with intermediate strength of the ionic bonds are ductile and yield at very large shear strain due to the self-healing properties and the dynamic association-dissociation of the ionic *** the self-healing properties disappear when the ionic bond strength is too weak or too *** work reveals the mechanism of how the dynamic association-dissociation of ionic bonds influences both the linear and non-linear viscoelastic properties of the polyampholyte gels.

关键词： Polyampholyte gel Ionic bond Topological entanglement Self-healing Hierarchical structure

A Terbium(Ⅲ)-organic Coordination Polymer:Synthesis,Characterization and Its Luminescence

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Chinese Journal of Structural Chemistry 2022年第2期41卷 79-84,I0009页

作者： MI Ying-Hao yang ming-xue KUANG Xiao-Fei LU Can-Zhong State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China College of Chemistry and Materials Science Fujian Normal UniversityFuzhou 350007China University of Chinese Academy of Sciences Beijing 100049China

A new 3D terbium(Ⅲ)metal-organic network[Tb(HIMDC)(HCOO)(H_(2)O)]_(n)(complex 1)has been synthesized by Tb^(3+)ions coordinated with 4,5-imidazole dicarboxylic acid(H_(3)IMDC)and formic acid under solvothermal conditions with the mixed solvents of N,N-dimethylformamide(DMF)and H_(2)*** unambiguous structural determination has been confirmed by single-crystal X-ray diffraction combined with elemental analysis,infrared(IR)spectrum,thermogravimetric analysis(TGA)and powder X-ray diffraction(PXRD).Complex 1crystallizes in orthorhombic Fdd2 space group with a=22.295(2),b=24.097(3),c=6.7256(6)?,V=3613.3?^(3),Z=16,D_(c)=2.765 g/cm^(3),F(000)=2816,μ=7.855 mm^(-1),the final R=0.0173(I≥2σ(I)),w R=0.0416(all data)and GOOF=*** complex 1,the Tb^(3+)ions are connected by HIMDC^(2-)anions into 2D metal-organic layers which are further extended into a three-dimensional(3D)architecture through formic acid functional *** addition,complex 1 shows intense and characteristic green luminescence.

关键词： coordination polymer crystal structure photoluminescence

Short-Term Impacts of No Tillage on Aggregate-Associated C in Black Soil of Northeast China

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Agricultural Sciences in China 2010年第1期9卷 93-100页

作者： LIANG Ai-zhen yang xue-ming ZHANG Xiao-ping SHEN Yan SHI Xiu-huan FAN Ru-qin FANG Hua-jun Northeast Institute of Geography and Agroecology Chinese Academy of Sciences Changchun 130012 P.R.China Greenhouse ＆ Processing Crops Research Centre Agriculture ＆ Agri-Food Canada Ontario NOR 1G0 Canada Institute of Geographic Sciences and Natural Resources Research Centre Chinese Academy of Sciences Beijing 100101 P.R.China

In order to get a good indicator to evaluate the impacts of no tillage （NT） on soil structure and soil quality, we studied the dynamics of total soil organic carbon （SOC） and aggregate-associated SOC, and their relationships in the plow layer （30 cm） in black soil of Northeast China under NT practice. The tillage experiment was established in Dehui County, Jilin Province, China, in 2001. The total SOC and aggregate-associated SOC under 5-yr tillage treatments were measured. NT practices did not lead to the increase of average SOC content at 0-30 cm depth, but it did significantly increase SOC at the top soil （0-5 cm）. In NT plots, the change of SOC in 〉 1 000 μm aggregate was the same with that of total SOC, but the effect of NT on SOC in 〉 1 000 lain aggregate was greater than the effect on total SOC, suggesting that 〉 1 000 μm aggregate had more sensitive response to the impact of tillage practices. Also, significant positive correlation occurred between total SOC and SOC in 〉 1 000 μm aggregate in black soil. Consequently, in the short term soil macroaggregate 〉 1 000 μm could be used as an indicator to evaluate the impacts of tillage practices on soil structure in black soil of Northeast China.

关键词： no tillage soil organic carbon water-stable aggregate black soil

Advanced Materials for NH_(3)Capture:Interaction Sites and Transport Pathways

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Nano-Micro Letters 2024年第11期16卷 119-155页

作者： Hai‑Yan Jiang Zao‑ming Wang xue‑Qi Sun Shao‑Juan Zeng yang‑yang Guo Lu Bai ming‑Shui Yao Xiang‑Ping Zhang Key Laboratory of Green Process and Engineering State Key Laboratory of Mesoscience and EngineeringBeijing Key Laboratory of Ionic Liquids Clean ProcessInstitute of Process EngineeringChinese Academy of SciencesBeijing 100190People’s Republic of China School of Future Technology University of Chinese Academy of SciencesBeijing 100049People’s Republic of China China University of Petroleum Beijing 102249People’s Republic of China Institute for Integrated Cell‑Material Sciences(iCeMS) Kyoto UniversitySakyo‑KuYoshidaKyoto 606‑8501Japan

Ammonia(NH3)is a carbon-free,hydrogen-rich chemical related to global food safety,clean energy,and environmental *** an essential technology for meeting the requirements raised by such issues,NH3 capture has been intensively explored by researchers in both fundamental and applied *** four typical methods used are(1)solvent absorption by ionic liquids and their derivatives,(2)adsorption by porous solids,(3)abadsorption by porous liquids,and(4)membrane *** in the development of advanced materials for NH3 capture,we conducted a coherent review of the design of different materials,mainly in the past 5 years,their interactions with NH3 molecules and construction of transport pathways,as well as the structure–property relationship,with specific examples ***,the challenges in current research and future worthwhile directions for NH3 capture materials are proposed.

关键词： Ammonia capture Solvents Porous solids Porous liquids Membranes