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Geodesy and Geodynamics 2022年第4期13卷 327-342页

作者： Wenguan jiang wei You Faculty of Geosciences and Environmental Engineering Southwest Jiaotong UniversityChengdu 611756China Third Geodetic Team of the Department of Natural Resources Chengdu 610100China State-Province Joint Engineering Laboratory of Spatial Information Technology for High-Speed Railway Safety Chengdu 610031China

During the satellite pulse propagation and reception, the altimeter waveform is inevitably affected by noise. To reduce the noise level in Jason altimeter waveforms, we used singular spectrum analysis(SSA),empirical mode decomposition(EMD), and the combination of SSA and EMD to obtain the denoised waveforms. The advantages of the combined method were verified and the accuracy of the mean sea surface height(MSSH) model was improved. Comparing the denoising effect of the three methods, the results show that the signal-to-noise ratio(SNR), correlation coefficient and root-mean-square error are effectively improved by the combination of SSA and EMD. The sea surface heights(SSHs) were remeasured with a 50% threshold retracker of denoised waveforms, and the MSSH model of the Caspian Sea with a grid of 1’× 1’was established from the retracked SSHs of Jason-1/2/3. Taking the mean value of the four models as a control, it is found that the model calculated by the combined denoising method has the highest accuracy. This indicates that using the combined denoising method to reduce the noise level is beneficial to improve the accuracy of the MSSH model.

关键词： Altimetry waveforms Jason-1/2/3 Combined method Waveform retracking Mean sea surface height

Simulated annealing reconstruction and characterization of a LiCoO＿2 Lithium-ion battery cathode

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Chinese Science Bulletin 2013年第36期58卷 4692-4695页

作者： WU wei jiang FangMing Laboratory of Advanced Energy Systems Key Laboratory of Renewable Energy and Gas Hydrate Guangzhou Institute of Energy ConversionChinese Academy of Sciences

We reconstruct the three-dimensional microstructure of a cathode from a commercial LiCoO2Lithium-ion battery with an adapted simulated annealing *** real size distribution curve of LiCoO2particles is applied to regulate the reconstruction *** discretizing a 40 m 40 m 40 m cathode volume with 8000000 numerical cubes,the cathode involving three individual phases:(1)LiCoO2as active material,(2)pores or electrolyte,and(3)additives(polyvinylidene fluoride+carbon black)is *** of the reconstructed cathode gives important structural and transport properties including volume-specific surface area between phases,tortuosity and geometrical connectivity of individual phase.

关键词：模拟退火方法锂离子电池钴酸锂阴极三维微结构表征聚偏氟乙烯分布曲线

FIELD TEST OF FLOATING OPEN CAISSON IN QIANTANG ESTUARY

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China Ocean Engineering 1990年第3期5卷 249-260页

作者： wei, jiang Zhejiang Provincial Inst of Estuarine and Coastal Engineering Research Hangzhou China

This paper attempts to deal with a whole testing process of a floating open caisson in the strong tidal Qiantang Estuary. It offers an over-all description of the open caisson's type selection, main principles regarding its structure design, building, floating, sinking, the joining of two open caissons and the operation of declination correction as well. In addition, the type of the open caisson, its self sinking, declination and swing in the test process are discussed in detail. All of these experiments might be quite useful in the building of a floating open caisson in similar strong tidal rivers.

关键词： Rivers Estuaries

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甲基纤维素对卵巢摘除大鼠的减肥作用

上海实验动物科学 2003年第3期23卷 163-165页

作者：乔伟伟周文江许兰文复旦大学实验动物科学部上海200032

研究不同剂量甲基纤维素(MethylcelluloseM450)对卵巢摘除中老年雌性大鼠体重的调节作用。对6月龄雌性大鼠施卵巢切除术后4个月起胃饲高中低三种剂量甲基纤维素30d,观察其体重、腹腔脂肪重量、脂肪细胞数量、大小、血脂、血胆固醇水平... 详细信息

研究不同剂量甲基纤维素(MethylcelluloseM450)对卵巢摘除中老年雌性大鼠体重的调节作用。对6月龄雌性大鼠施卵巢切除术后4个月起胃饲高中低三种剂量甲基纤维素30d,观察其体重、腹腔脂肪重量、脂肪细胞数量、大小、血脂、血胆固醇水平的变化。结果显示,给予甲基纤维素100mg/kg(中剂量)和200mg/kg(高剂量)组,大鼠体重、腹腔脂肪重量及脂肪细胞大小均明显低于对照组(P100mg/kg)甲基纤维素组对卵巢摘除的中老年大鼠有明显减肥作用,并有一定降血脂作用。30mg/kg(低剂量)纤维素组则无作用(P>0.05)。

关键词：甲基纤维素卵巢摘除大鼠减肥作用体重

Ultra‑High Sensitivity Anisotropic Piezoelectric Sensors for Structural Health Monitoring and Robotic Perception

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Nano-Micro Letters 2025年第2期17卷 432-446页

作者： Hao Yin Yanting Li Zhiying Tian Qichao Li Chenhui jiang Enfu Liang Yiping Guo State Key Laboratory of Metal Matrix Composites School of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai 200240People’s Republic of China Beijing Vacuum Electronics Research Institute Beijing 100015People’s Republic of China Fundamental Science On Vibration Shock and Noise LaboratoryState Key Laboratory of Mechanical System and VibrationSchool of Mechanical EngineeringShanghai Jiao Tong UniversityShanghai 200240People’s Republic of China

Monitoring minuscule mechanical signals,both in magnitude and direction,is imperative in many application scenarios,e.g.,structural health monitoring and robotic sensing ***,the piezoelectric sensor struggles to satisfy the requirements for directional recognition due to the limited piezoelectric coefficient matrix,and achieving sensitivity for detecting micrometer-scale deformations is also ***,we develop a vector sensor composed of lead zirconate titanate-electronic grade glass fiber composite filaments with oriented arrangement,capable of detecting minute anisotropic *** as-prepared vector sensor can identify the deformation directions even when subjected to an unprecedented nominal strain of 0.06%,thereby enabling its utility in accurately discerning the 5μm-height wrinkles in thin films and in monitoring human pulse *** ultra-high sensitivity is attributed to the formation of porous ferroelectret and the efficient load transfer efficiency of continuous lead zirconate titanate ***,when integrated with machine learning techniques,the sensor’s capability to recognize multi-signals enables it to differentiate between 10 types of fine textures with 100%*** structural design in piezoelectric devices enables a more comprehensive perception of mechanical stimuli,offering a novel perspective for enhancing recognition accuracy.

关键词： Flexible piezoelectric filaments Anisotropic Ultra-high sensitivity Structural health detection Texture recognition

An extended numerical model of the first exothermic peak for three dimensional printed cement-based materials

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Frontiers of Structural and Civil Engineering 2024年第1期18卷 80-88页

作者： wei jiang Wenqian LI Xi CHEN School of Materials Science and Engineering Tongji UniversityShanghai 200092China School of Civil Engineering Tongji UniversityShanghai 200092China

The first exothermic peak of cement-based material occurs a few minutes after mixing,and the properties of three dimensional(3D)printed concrete,such as setting time,are very sensitive to *** this background,based on the classical Park cement exothermic model of hydration,we propose and construct a numerical model of the first exothermic peak,taking into account the proportions of C_(3)S,C_(3)A and quicklime in *** calculated parameters are calibrated by means of relevant published exothermic test *** is found that this developed model offers a good simulation of the first exothermic peak of hydration for C_(3)S and C_(3)A proportions from 0 to 100% of cement clinker and reflects the effect of quicklime content at 8%-10%.The unique value of this research is provision of an important computational tool for applications that are sensitive to the first exothermic peak of hydration,such as 3D printing.

关键词： 3D printed cement-based materials cement hydration the first exothermic peak liquid quick-setting agent numerical model

A Multi-Objective Optimization Method of Initial Virtual Machine Fault-Tolerant Placement for Star Topological Data Centers of Cloud Systems

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Tsinghua Science and Technology 2021年第1期26卷 95-111页

作者： wei Zhang Xiao Chen Jianhui jiang the School of Software Engineering Tongji UniversityShanghai 201804China

Virtualization is the most important technology in the unified resource layer of cloud computing *** placement and dynamic management are two types of Virtual Machine(VM)management *** dynamic management is based on the structure of the initial VM placement,and this initial structure will affect the efficiency of VM dynamic *** a VM fails,cloud applications deployed on the faulty VM will crash if fault tolerance is not *** this study,a model of initial VM fault-tolerant placement for star topological data centers of cloud systems is built on the basis of multiple factors,including the service-level agreement violation rate,resource remaining rate,power consumption rate,failure rate,and fault tolerance ***,a heuristic ant colony algorithm is proposed to solve the *** service-providing VMs are placed by the ant colony algorithms,and the redundant VMs are placed by the conventional heuristic *** experimental results obtained from the simulation,real cluster,and fault injection experiments show that the proposed method can achieve better VM fault-tolerant placement solution than that of the traditional first fit or best fit descending method.

关键词： cloud computing virtual machine placement fault tolerance multi-objective optimization heuristic ant colony algorithm

Correlation analyse between thyroid hormone levels and severity of schizophrenia symptoms

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World Journal of Psychiatry 2025年第1期15卷 63-71页

作者： Qi-Hui jiang wei-Dong Gong Department of Endocrinology and Metabolism Hengyang Central HospitalHengyang 421000Hunan ProvinceChina Breast Tumor Surgical Outpatient Hengyang Central HospitalHengyang 421000Hunan ProvinceChina

BACKGROUND The imbalance of hormone levels in the body is closely related to the occurrence and progression of schizophrenia,especially thyroid *** To study the relationship between triiodothyronine(T3),thyroxine(T4),free T3(FT3),free T4(FT4),thyroid stimulating hormone(TSH)and *** In this study,100 schizophrenia patients were selected from our hospital between April 2022 and April *** clinical data were analyzed *** on the Positive and Negative Syndrome Scale(PANSS)score,patients were divided into mild(1-3 points,n=39),moderate(4 points,n=45),and severe groups(5-7 points,n=16).Additionally,55 healthy individuals served as a control *** blood samples were collected to measure T3,T4,FT3,FT4,TSH,and cortisol concentrations,analyzing their relationship with PANSS *** The serum levels of T3,FT3,FT4,TSH and cortisol in the schizophrenia group were lower than those in the control group(P<0.05).With the increase of the severity of the disease,the concentrations of T3 and T4 decreased,while the con-centrations of TSH and cortisol increased(P<0.05).The concentrations of TSH and cortisol were positively correlated with the PANSS score,while T3 and T4 were negatively correlated with the PANSS score(P<0.05).The receiver ope-rating characteristic curve results showed that T3,T4,TSH,and cortisol had good efficacy in the diagnosis of *** results showed that decreased T3 level,decreased T4 level,decreased TSH level and increased cortisol level may be independent risk factors for *** Thyroid hormone levels are associated with the severity of schizophrenia symptoms,which can provide new solutions for the diagnosis and treatment of schizophrenia.

关键词： Thyroid hormone Schizophrenia Symptom severity Positive and Negative Syndrome Scale score Cortisol

A New Model for Quark Mass Matrix

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Chinese Physics Letters 2011年第6期28卷 71-73页

作者： jiang Zhi-wei Department of Modern Physics University of Science and Technology of ChinaHefei 230026

We study the status of S3,i.e.a slightly broken symmetry of quarks and propose a new model in which the S3 symmetry among the three generation up−quarks is slightly broken into the C2 symmetry while the S3 symmetry of... 详细信息

关键词： symmetry quark slightly

AlH_(3)as a hydrogen storage material:recent advances,prospects and challenges

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Rare Metals 2021年第12期40卷 3337-3356页

作者： wei jiang Hui Wang Min Zhu Guangdong Provincial Key Laboratory of Advanced Energy Storage Materials School of Materials Science and EngineeringSouth China University of TechnologyGuangzhou510641China

Aluminum hydride(AlH_(3))is a covalently bonded trihydride with a high gravimetric(10.1 wt%)and volumetric(148 kg·m^(-3))hydrogen ***_(3)decomposes to Al and H_(2)rapidly at relatively low temperatures,indicating good hydrogen desorption kinetics at ambient ***,AlH_(3)is one of the most prospective candidates for high-capacity hydrogen storage ***,this review briefly summarizes the basic chemical and physical characteristics of AlH_(3).Then,its synthesis,dehydrogenation thermodynamics and kinetics,regeneration and methods for improving reversibility of hydriding are described with the aim of applying this material for hydrogen *** accordance with the fact that AlH_(3)is generally formed by reacting Al with H_(2)at extremely high hydrogen pressure,the high-pressure study of this hydride is discussed in ***,the advantages,weaknesses,critical technical challenges and outlook of this field are discussed.

关键词： Aluminum hydride AlH_(3) Hydrogen storage High pressure