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Algorithms and statistical analysis for linear structured weighted total least squares problem

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Geodesy and Geodynamics 2024年第2期15卷 177-188页

作者： jian Xie Tianwei qiu Cui Zhou Dongfang Lin Sichun Long School of Earth Science and Spatial Information Engineering Hunan University of Science and TechnologyXiangtan 411201China College of Science Central South University of Forestry and TechnologyChangsha 410018China National-Local Joint Engineering Laboratory of Geo-spatial Information Technology Hunan University of Science and TechnologyXiangtan 411201China

Weighted total least squares(WTLS)have been regarded as the standard tool for the errors-in-variables(EIV)model in which all the elements in the observation vector and the coefficient matrix are contaminated with random ***,in many geodetic applications,some elements are error-free and some random observations appear repeatedly in different positions in the augmented coefficient *** is called the linear structured EIV(LSEIV)*** kinds of methods are proposed for the LSEIV model from functional and stochastic *** the one hand,the functional part of the LSEIV model is modified into the errors-in-observations(EIO)*** the other hand,the stochastic model is modified by applying the Moore-Penrose inverse of the cofactor *** algorithms are derived through the Lagrange multipliers method and linear *** estimation principles and iterative formula of the parameters are proven to be *** first-order approximate variance-covariance matrix(VCM)of the parameters is also derived.A numerical example is given to compare the performances of our proposed three algorithms with the STLS ***,the least squares(LS),total least squares(TLS)and linear structured weighted total least squares(LSWTLS)solutions are compared and the accuracy evaluation formula is proven to be feasible and ***,the LSWTLS is applied to the field of deformation analysis,which yields a better result than the traditional LS and TLS estimations.

关键词： Linear structured weighted total least squares Errors-in-variables Errors-in-observations Functional modelmodification Stochastic model modification Accuracyevaluation

High-yield production of porous carbon spheres derived from enzymatic hydrolysis lignin for zinc ion hybrid capacitors

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Frontiers of Chemical Science and Engineering 2024年第2期18卷 127-136页

作者： Tao Huang Xihong Zu jianhui Ma Wenbin jian Xueqing qiu Wenli Zhang Guangdong Provincial Key Laboratory of Plant Resources Biorefinery School of Chemical Engineering and Light IndustryGuangdong University of TechnologyGuangzhou 510006China School of Advanced Manufacturing Guangdong University of TechnologyJieyang 522000China Jieyang Branch of Chemistry and Chemical Engineering Guangdong Laboratory(Rongjiang Laboratory) Jieyang 515200China

The widespread implementation of supercapacitors is hindered by the limited energy density and the pricey porous carbon electrode *** cost of porous carbon is a significant factor in the overall cost of supercapacitors,therefore a high carbon yield could effectively mitigate the production cost of porous *** study proposes a method to produce porous carbon spheres through a spray drying technique combined with a carbonization process,utilizing renewable enzymatic hydrolysis lignin as the carbon source and KOH as the activation *** purpose of this study is to examine the relationship between the quantity of activation agent and the development of morphology,pore structure,and specific surface area of the obtained porous carbon *** demonstrate that this approach significantly enhances the carbon yield of porous carbon,achieving a yield of 22%in contrast to the conventional carbonization-activation method(9%).The samples acquired through this method were found to contain a substantial amount of mesopores,with an average pore size of 1.59 to 1.85 nm and a mesopore ratio of 25.6%.Additionally,these samples showed high specific surface areas,ranging from 1051 to 1831 m2·g^(−1).Zinc ion hybrid capacitors with lignin-derived porous carbon cathode exhibited a high capacitance of 279 F·g^(−1) at 0.1 A·g^(−1) and an energy density of 99.1 Wh·kg^(−1) when the power density was 80 kW·kg^(−1).This research presents a novel approach for producing porous carbons with high yield through the utilization of a spray drying approach.

关键词： enzymatic hydrolysis lignin porous carbon spheres spray drying zinc ion hybrid capacitors

Exact Box-Constrained Economic Operating Region for Power Grids Considering Renewable Energy Sources

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Journal of Modern Power Systems and Clean Energy 2024年第2期12卷 514-523页

作者： Huating Xu Bin Feng Chutong Wang Chuangxin Guo jian qiu Mingyang Sun College of Electrical Engineering Zhejiang UniversityHangzhou 310027China Department of Control Science and Engineering Zhejiang UniversityHangzhou 310027China

The growing integration of renewable energy sources manifests as an effective strategy for reducing carbon emissions. This paper strives to efficiently approximate the set of optimal scheduling plans(OSPs) to enhance the performance of the steady-state adaptive cruise method(SACM) of power grid, improving the ability of dealing with operational uncertainties. Initially, we provide a mathematical definition of the exact boxconstrained economic operating region(EBC-EOR) for the power grid and its dispatchable components. Following this, we introduce an EBC-EOR formulation algorithm and the corresponding bi-level optimization models designed to explore the economic operating boundaries. In addition, we propose an enhanced big-M method to expedite the computation of the EBCEOR. Finally, the effectiveness of the EBC-EOR formulation, its economic attributes, correlation with the scheduling plan underpinned by model predictive control, and the significant improvement in computational efficiency(over twelvefold) are verified through case studies conducted on two test systems..

关键词： Exact box-constrained economic operating region(EBC-EOR) big-M method intelligent scheduling steady-state adaptive cruise uncertainty renewable energy source

Effect of Tanshinone IIA on High Glucose-induced Apoptosis and Oxidative Stress Damage in Vascular Endothelial Cells

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Chinese Journal of Biomedical Engineering 2024年第2期33卷 62-68页

作者： qiu Shui-lin HUANG Rong HUANG jian-qing qiu Rong-shui Longyan First Affiliated Hospital of Fujian Medical University Xiamen Medical College Affiliated Haicang Hospital

Objective: The primary cause of microvascular disease in diabetic complications is long-term hyperglycemia, wherein the damage and apoptosis of vascular endothelial cells play a significant role. Sodium tanshinone IIA sulfonate(STS) has been found to have beneficial effects on cardiovascular health. This study aimed to investigate the impact of STS on high glucose-induced apoptosis and oxidative stress damage in vascular endothelial cells, as well as its potential protective mechanisms. Methods:Human umbilical vein endothelial cells(HUVECs) were divided into five groups:low-glucose group, high-glucose group, and three STS groups(STS-a, STS-b, and STS-c). The low-glucose group was incubated with DMEM low-sugar medium containing 5.5 mmol·L-1glucose, while the high-glucose group was treated with 33.3mmol·L-1glucose. The STS groups were exposed to 10, 30, and 50 μg·m L-1of STS,respectively. Each group was cultured for 72 h, and the MTT method was utilized to assess cell proliferation. Additionally, flow cytometry was employed to monitor changes in cell apoptosis and cellular oxidative stress indicators at 24, 48, and 72 h of cell culture in each group. Results: As time went on, the cell proliferation ability and apoptosis rate of each group gradually increased. The high-glucose group exhibited lower proliferation ability compared to the other groups. The STS-c group demonstrated the highest OD value for proliferation ability(24 h: 1.19±0.12; 48 h: 1.20±0.13; 72 h:1.25 ±0.12), but it was still lower than that of the low-sugar group. Notably, the high-glucose group had the highest cell apoptosis rate, while the low-glucose group had the lowest. The apoptosis rate of the STS-c group(24 h: 8.02±0.13; 48 h: 10.10±0.12;72 h: 13.18 ±0.11)% was between that of the low-glucose group and the high-glucose group, and lower than the STS-a and STS-b groups. Furthermore, the high-glucose group exhibited the highest malondialdehyde and nitric oxide synthase activities, as well as super

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Problem identification and revitalization strategies for the recovery and reconstruction of traditional villages in the Ms 6.8 Luding Earthquake

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Journal of Mountain Science 2024年第2期21卷 361-379页

作者： HUANG Chao qiu jian LIU Chun jianG Rui ZHAO Chuanrong ZHANG Yi School of Architecture and Research Center of Space Planning and Engineering Design Southwest Jiaotong UniversityChengdu 611756China Sichuan Provincial Rural Construction and Development Center Chengdu 610041China Sichuan Institute of Urban and Rural Construction Chengdu 610043China China Association for Promoting Democracy(CAPD)Sichuan Provincial Committee Chengdu 610016China Sichuan Provincial Architectural Design and Research Institute(SADI) Chengdu 610095China

Post-disaster reconstruction is a topic of global concern,and traditional villages have special heritage attributes and need to face more requirements and obstacles in post-disaster *** paper summarizes four concepts based on the research on post-disaster reconstruction both domestically and internationally,as well as the recovery and reconstruction of cultural *** a field survey of traditional villages in the Ms 6.8 Luding earthquake-stricken area,it is found that there are problems such as insufficient awareness of heritage value,misalignment of scientific reconstruction technology,and insufficient protection of reconstruction elements during the reconstruction *** villages face the risk of declining or even loss of heritage *** order to effectively protect traditional villages and inherit the carrier of regional culture,four targeted reconstruction response strategies are proposed,i.e.,to"establish special planning for traditional village preservation","emphasize recovery of the authenticity of village heritage","ensure elements for village heritage recovery"and"promote the activation and utilization of village heritage",based on the problems discovered during the survey and the four concepts summarized in the research on post-disaster reconstruction of traditional *** research results hope to provide useful reference for ancient cultural areas affected by earthquakes on how to protect cultural heritage during the post-disaster reconstruction process.

关键词： Seismic hazard Decision making Traditional village Cultural heritage protection Post-earthquake recovery and reconstruction Revitalization strategy

Effects of Hydrogen Charging Time and Pressure on the Hydrogen Embrittlement Susceptibility of X52 Pipeline Steel Material

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Acta Metallurgica Sinica(English Letters) 2024年第2期37卷 293-307页

作者： Hong-jiang Wan Xiao-Qi Wu Hong-Liang Ming jian-qiu Wang En-Hou Han School of Materials Science and Engineering University of Science and Technology of ChinaShenyang110016China CAS Key Laboratory of Nuclear Materials and Safety Assessment Institute of Metal ResearchChinese Academy of SciencesShenyang110016China School of Materials Science and Engineering Northeastern UniversityShenyang110819China Institute of Corrosion Science and Technology Guangzhou510530China

The effects of hydrogen charging time and pressure on the hydrogen embrittlement(HE)susceptibility of X52 pipeline steel material are studied by slow strain rate tensile *** fracture morphologies of the specimens are observed by scanning electron *** HE susceptibility of the X52 pipeline steel material increases with an increase in both hydrogen charging time and hydrogen *** a charging time of 96 h,the HE susceptibility index reaches 45.86%,approximately 3.6 times that at a charging time of 0 ***,a charging pressure of 4 MPa results in a HE susceptibility index of 31.61%,approximately 2.5 times higher than that at a charging pressure of 0.3 MPa.

关键词： Hydrogen embrittlement X52 pipeline steel material Tubular specimen Hydrogen charging time Hydrogen charging pressure

Synthetic Control of Thorium Metal-Organic Frameworks for Sequencing and Sensing of Radioiodine Species

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Chinese Journal of Chemistry 2024年第1期42卷 20-28,I0004页

作者： Yu Ju Zi-jian Li xue Wang Jie qiu Yiuhon Chan Zhi-Hui Zhang Mingyang He jian Lin jiangsu Key Laboratory of Advanced Catalytic Materials and Technology Changzhou UniversityNo.21Gehu Middle RoadChangzhouJiangsu 213164China Schoolof Nuclear Science and Technology Xi'an Jiaotong UniversityNo.28West Xianning RoadXianShaanxi 710049China Key Laboratoryof Interfacial Physics and Technology Shanghai Institute of Applied PhysicsChinese Academy of Sciences2019JiaLuoRoadShanghai 201800China

Exploring the physiochemical properties and expanding the applications of actinide-containing materials is paramount to address the escalating challenge of radioactive waste ***,unlocking the full potential of these materials is largely crippled by the radiotoxicity of the *** report here two porous and luminescent thorium-based metal-organic frameworks(Th-BITD-1 and Th-BITD-2)that serve as a bifunctional platform for sequencing and sensing of radioiodine,a much more radioactive fission product discharged during the nuclear fuel *** particular,Th-BITD-1 displays better iodine uptake performance than Th-BITD-2 via the solution-based process and vapor diffusion with the maximum adsorption capacities of 831 and 1099 mg/g,*** thermore,Th-BITD-1 can function as a highly sensitive luminescence sensor for iodate with a quenching constant(Ksv)of 6.6(5)×10^(3) M^(-1)and a detection limit of 2.02μM,respectively,outperforming 2.96(6)×10^(3)M^(-1)and 10.5μM of ***,a positive correlation between the sensing efficacy and the iodate adsorption capacity has been *** work highlights the opportunity in designing novel actinide-based MOFs for their potential applications in radiological fields,e.g.,radionuclide separation and detection.

关键词： Thorium Metal-organic frameworks Adsorption Detection lodine Actinides Radiochemistry Luminescence

Understanding the Thermal Impedance of Silicone Rubber/Hexagonal Boron Nitride Composites as Thermal Interface Materials

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Chinese Journal of Polymer Science 2024年第3期42卷 352-363,I0008页

作者： Yuan Ji Shi-Da Han Hong Wu Shao-Yun Guo Feng-Shun Zhang jian-Hui qiu The State Key Laboratory of Polymer Materials Engineering Sichuan Provincial Engineering Laboratory of Plastic/Rubber Complex Processing TechnologyPolymer Research InstituteSichuan UniversityChengdu 610065China Institute of Chemical Materials China Academy of Engineering PhysicsMianyang 621900China Department of Mechanical Engineering Faculty of Systems Science and TechnologyAkita Prefectural UniversityAkita 015-0055Japan

Silicone rubber(SR) composites are most widely used as thermal interface materials(TIMs) for electronics heat dissipation. Thermal impedance as the main bottleneck limiting the performance of TIMs is usually neglected. Herein, the thermal impedance of SR composites loaded with different levels of hexagonal boron nitride(h-BN) as TIMs was elaborated for the first time by the ASTM D 5470 standard test and finite element analysis. It was found that elastic modulus and surface roughness of SR composites increased with the increase of h-BN content, indicating that the conformity was reduced. When the assembly pressure was 0.69 MPa, there existed an optimal h-BN content at which the contact resistance was minimum(0.39 K·cm^(2)·W^(-1)). Although the decreased bond line thickness(BLT) by increasing the assembly pressure was beneficial to reduce the thermal impedance, the proper assembly pressure should be selected to prevent the warpage of the contact surfaces and the increase in contact resistance, according to the compression properties of the SR composites. This study provides valuable insights into fabrication of high-performance TIMs for modern electronic device applications.

关键词： Thermal interface materials Hexagonal boron nitride Thermal impedance Surfaces

Mechanical properties of multi-scale germanium specimens from space solar cells under electron irradiation

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Chinese Journal of Aeronautics 2024年第1期37卷 173-185页

作者： jian qiu Maliya HEINI Jusha MA Wenjia HAN Xunchun WANG Jun YIN Yan SHI Cunfa GAO State Key Laboratory of Mechanics and Control of Mechanical Structures Nanjing University of Aeronautics and AstronauticsNanjing 210016China School of Chemistry and Civil Engineering Shaoguan UniversityShaoguan 512005China Key Laboratory of Functional Materials and Devices for Special Environments of Chinese Academy of Sciences Chinese Academy of SciencesUrumqi 830011China Shanghai Institute of Space Power-Sources Shanghai 200245China

During long-term service in space,Gallium Arsenide(GaAs)solar cells are directly exposed to electron irradiation which usually causes a dramatic decrease in their *** the multilayer structure of solar cells,the germanium(Ge)layer occupies the majority of the thickness as the *** to the intrinsic brittleness of semiconductor material,there exist various defects during the preparation and assembly of solar cells,the influences of which tend to be intensified by the irradiation *** this work,first,Ge specimens for mechanical tests were prepared at scales from microscopic to ***,after different doses of electron irradiation,the mechanical properties of the Ge specimens were *** experimental results demonstrate that electron irradiation has an obvious effect on the mechanical property variation of Ge in diverse *** four-point bending test indicates that the elastic modulus,fracture strength,and maximum displacement of the Ge specimens all increase,and reach the maximum value at the irradiation dose of 1×10^(15)e/cm^(2).The micrometer scale cantilever and nanoindentation tests present similar trends for Ge specimens after *** Force Microscope(AFM)also observed the change in surface ***,a fitting model was established to characterize the relation between modulus change and electron irradiation dose.

关键词： Electron irradiation Germanium Mechanical properties Multi-scale Space solar cells