检索结果-南通市图书馆

基于Stacking模型融合策略的日本俯冲带板缘地震动预测

在线全文

学校读者我要写书评

暂无评论

世界地震工程 2024年第1期40卷 80-95页

作者：党浩天王自法赵登科位栋梁王祥琪 wang jianming 李兆焱河南大学土木建筑学院河南开封475001 中国地震局工程力学研究所黑龙江哈尔滨150080 地震灾害防治应急管理部重点实验室黑龙江哈尔滨150080 中震科建(广东)防灾减灾研究院广东韶关512000

高精度的地震动预测模型有助于提高地震灾害的预警和应对能力。传统回归方法构建地震动预测模型时提前设定了方程的形式,此种方法存在一定局限性,难以反映地震动传播过程中的复杂规律,因此越来越多的学者尝试应用机器学习方法构建地震... 详细信息

高精度的地震动预测模型有助于提高地震灾害的预警和应对能力。传统回归方法构建地震动预测模型时提前设定了方程的形式,此种方法存在一定局限性,难以反映地震动传播过程中的复杂规律,因此越来越多的学者尝试应用机器学习方法构建地震动预测模型。但采用单一的机器学习算法,难以从数据中捕捉到更多规律,最终导致模型精度难以提升。本文基于日本KiK-net和K-Net强震台网收集到的俯冲带板缘地震动记录,使用Stacking模型融合策略,以LightGBM、XGBoost和CatBoost算法作为基学习器,线性回归算法作为元学习器,引入客观且高效的贝叶斯优化算法对模型进行超参数优化,最终训练并提出了一种适用于日本俯冲带板缘地震动预测的融合模型Stacking-Interface。对比分析所提出模型、单一机器学习模型和传统模型,发现机器学习模型的精度普遍高于传统模型,且相较于单一的机器学习模型,融合模型的预测能力有一定的提升;通过与实际地震动记录的对比和特征参数敏感性分析,验证了所提模型的可靠性和泛化能力。研究方法和结果能够为地震风险分析提供参考。

关键词：地震动预测 Stacking 俯冲带板缘地震部分依赖图

Layered Structural PBAT Composite Foams for Efficient Electromagnetic Interference Shielding

在线全文

学校读者我要写书评

暂无评论

Nano-Micro Letters 2024年第2期16卷 273-286页

作者： jianming Yang Hu wang Yali Zhang Hexin Zhang Junwei Gu School of Chemistry and Chemical Engineering Anhui University of TechnologyMa’anshanAnhui 243032People’s Republic of China Shaanxi Key Laboratory of Macromolecular Science and Technology School of Chemistry and Chemical EngineeringNorthwestern Polytechnical UniversityXi’an 710072ShaanxiPeople’s Republic of China School of Materials Science and Engineering Jiangsu University of Science and TechnologyZhenjiang 212003JiangsuPeople’s Republic of China

The utilization of eco-friendly,lightweight,high-efficiency and high-absorbing electromagnetic interference(EMI)shielding composites is imperative in light of the worldwide promotion of sustainable manufacturing.In this work,magnetic poly(butyleneadipate-coterephthalate)(PBAT)microspheres were firstly synthesized via phase separation method,then PBAT composite foams with layered structure was constructed through the supercritical carbon dioxide foaming and scraping techniques.The merits of integrating ferroferric oxideloaded multi-walled carbon nanotubes(Fe3O4@MWCNTs)nanoparticles,a microcellular framework,and a highly conductive silver layer have been judiciously orchestrated within this distinctive layered configuration.Microwaves are consumed throughout the process of“absorption-reflection-reabsorption”as much as possible,which greatly declines the secondary radiation pollution.The biodegradable PBAT composite foams achieved an EMI shielding effectiveness of up to 68 dB and an absorptivity of 77%,and authenticated favorable stabilization after the tape adhesion experiment.

关键词： Electromagnetic interference shielding Layered structure Supercritical carbon dioxide foaming Poly(butyleneadipateco-terephthalate) Microcellular

Comparative analysis between single-train passing and double-train intersection in a tunnel

在线全文

学校读者我要写书评

暂无评论

Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2024年第5期25卷 429-442页

作者： jianming DU Qian FANG Xuan ZHANG Hualao wang Bridge and Tunnel Research Center Research Institute of Highway Ministry of TransportBejing 100088China Tunnel and Underground Engineering Research Center of Ministry of Education Beijing Jiaotong UniversityBeijing 00044China

Aerodynamic pressure significantly impacts the scientific evaluation of tunnel service performance.The aerodynamic pressure of two trains running in a double-track tunnel is considerably more complicated than that of a single train.We used the numerical method to investigate the difference in aerodynamic pressure between a single train and two trains running in a double-track tunnel.First,the numerical method was verified by comparing the results of numerical simulation and on-site monitoring.Then,the characteristics of aerodynamic pressure were studied.Finally,the influence of various train-tunnel factors on the characteristics of aerodynamic pressure was investigated.The results show that the aerodynamic pressure variation can be divided into stage I:irregular pressure fluctuations before the train tail leaves the tunnel exit,and stage II:periodic pressure declines after the train tail leaves the tunnel exit.In addition,the aerodynamic pressure simultaneously jumps positively or drops negatively for a single train or two trains running in double-track tunnel scenarios.The pressure amplitude in the two-train case is higher than that for a single train.The maximum positive peak pressure difference(P_(STP))and maximum negative peak pressure difference(P_(STN))increase as train speed rises to the power from 2.256 to 2.930 in stage I.The P_(STP) and P_(STN) first increase and then decrease with the increase of tunnel length in stage I.The P_(STP) and P_(STN) increase as the blockage ratio rises to the power from 2.032 to 2.798 in stages I and II.

关键词： Railway tunnel Aerodynamic effect Pressure characteristic Train speed Tunnel length Blockage ratio

Mechanical behaviors of warm and ice-rich frozen soil stabilized with sulphoaluminate cement

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Mountain Science 2024年第1期21卷 335-345页

作者： wang Honglei ZHANG Hu ZHANG jianming ZHANG Qi YIN Zhenhua State Key Laboratory of Frozen Soil Engineering Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China University of Chinese Academy of Sciences Beijing 100049China School of Civil Engineering and Transportation Northeast Forestry UniversityHarbin 150040China National Key Laboratory of Green and Long-Life Road Engineering in Extreme Environment CCCC First Highway Consultants Co.LtdXi'an 710065China Railway Engineering Research Institute China Academy of Railway Sciences Corporation LimitedBeijing 100081China

The warm and ice-rich frozen soil is characterized by high unfrozen water content, low shear strength and large compressibility, which is unreliable to meet the stability requirements of engineering infrastructures and foundations in permafrost regions. In this study, a novel approach for stabilizing the warm and ice-rich frozen soil with sulphoaluminate cement was proposed based on chemical stabilization. The mechanical behaviors of the stabilized soil, such as strength and stress-strain relationship, were investigated through a series of triaxial compression tests conducted at -1.0℃, and the mechanism of strength variations of the stabilized soil was also explained based on scanning electron microscope test. The investigations indicated that the strength of stabilized soil to resist failure has been improved, and the linear Mohr-Coulomb criteria can accurately reflect the shear strength of stabilized soil under various applied confining pressure. The increase in both curing age and cement mixing ratio were favorable to the growth of cohesion and internal friction angle. More importantly, the strength improvement mechanism of the stabilized soil is attributed to the formation of structural skeleton and the generation of cementitious hydration products within itself. Therefore, the investigations conducted in this study provide valuable references for chemical stabilization of warm and ice-rich frozen ground, thereby providing a basis for in-situ ground improvement for reinforcing warm and ice-rich permafrost foundations by soil-cement column installation.

关键词： Permafrost regions Frozen soil Mechanical behavior Chemical stabilization Ground improvement Ground modification

Experimental and numerical interpretation on composite foundation consisting of soil-cement column within warm and ice-rich frozen soil

在线全文

学校读者我要写书评

暂无评论

Journal of Mountain Science 2024年第1期21卷 313-321页

作者： wang Honglei ZHANG jianming WEI Shoucai SUN Zhizhong ZHANG Hu School of Civil Engineering Hebei University of EngineeringHandan 056038China State Key Laboratory of Frozen Soil Engineering Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China Second Geological Brigade Bureau of Geology and Mineral Resources Exploration and DevelopmentLhasa 850000China Da Xing’anling Observation and Research Station of Frozen Ground Engineering and Environment Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesJiagedaqi 165100China School of Civil Engineering Northeast Forestry UniversityHarbin 150040China

Affected by climate warming and anthropogenic disturbances, the thermo-mechanical stability of warm and ice-rich frozen ground along the Qinghai-Tibet engineering corridor(QTEC) is continuously decreased, which may delay the construction of major projects in the future. In this study, based on chemical stabilization of warm and icerich frozen ground, the soil-cement column(SCC) for ground improvement was recommended to reinforce the foundations in warm and ice-rich permafrost regions. To explore the validity of countermeasures mentioned above, both the original foundation and the composite foundation consisting of SCC with soil temperature of -1.0℃ were prepared in the laboratory, and then the plate loading tests were carried out. The laboratory investigations indicated that the bearing capacity of composite foundation consisting of SCC was higher than that of original foundation, and the total deformation of original foundation was greater than that of composite foundation, meaning that overall stability of foundation with warm and ice-rich frozen soil can be improved by SCC installation. Meanwhile, a numerical model considering the interface interaction between frozen soil and SCC was established for interpretating the bearing mechanism of composite foundation. The numerical investigations revealed that the SCC within composite foundation was responsible for the more applied load, and the applied load can be delivered to deeper zone in depth due to the SCC installation, which was favorable for improving the bearing characteristic of composite foundation. The investigations provide the valuable guideline for the choice of engineering supporting techniques to major projects within the QTEC.

关键词： Chemical stabilization Ground improvement Composite foundation Frozen soil engineering Qinghai-Tibet engineering corridor

Advances in the study of mitophagy in osteoarthritis

在线全文

学校读者我要写书评

暂无评论

Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2024年第3期25卷 197-211页

作者： Hong CAO Xuchang ZHOU Bowen XU Han HU jianming GUO Miao wang Nan LI Jun ZOU Department of Sport Rehabilitation Shanghai University of SportShanghai 200438China National Key Laboratory of Immunity and Inflammation Naval Medical UniversityShanghai 200433China School of Sport Medicine and Rehabilitation Beijing Sport UniversityBeijing 100084China

Osteoarthritis(OA),characterized by cartilage degeneration,synovial inflammation,and subchondral bone remodeling,is among the most common musculoskeletal disorders globally in people over 60 years of age.The initiation and progression of OA involves the abnormal metabolism of chondrocytes as an important pathogenic process.Cartilage degeneration features mitochondrial dysfunction as one of the important causative factors of abnormal chondrocyte metabolism.Therefore,maintaining mitochondrial homeostasis is an important strategy to mitigate OA.Mitophagy is a vital process for autophagosomes to target,engulf,and remove damaged and dysfunctional mitochondria,thereby maintaining mitochondrial homeostasis.Cumulative studies have revealed a strong association between mitophagy and OA,suggesting that the regulation of mitophagy may be a novel therapeutic direction for OA.By reviewing the literature on mitophagy and OA published in recent years,this paper elaborates the potential mechanism of mitophagy regulating OA,thus providing a theoretical basis for studies related to mitophagy to develop new treatment options for OA.

关键词： Mitophagy Osteoarthritis Chondrocyte Mitochondria Apoptosis

Efficient degradation of aqueous dichloromethane by an enhanced microbial electrolysis cell:Degradation kinetics,microbial community and metabolic mechanisms

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 2024年第5期139卷 150-159页

作者： Meng Wu Di Zhao Bing Gu Ziruwang Jun Hu Zhiliang Yu jianming Yu College of Environment College of Biotechnology and BioengineeringCollaborative Innovation Center of Yangtze River Delta Region Green PharmaceuticalsZhejiang University of TechnologyHangzhou 310014China Shentuo Environment(Hangzhou)Co.Ltd. Hangzhou 311121China Zhejiang Tianyi Environmental Co.Ltd. Hangzhou 310000China

Dichloromethane(DCM)has been listed as a toxic and harmful water pollutant,and its re moval needs attention.Microbial electrolysis cells(MECs)are viewed as a promising alterna tive for pollutant removal,which can be strengthened from two aspects:microbial inocula tion and acclimation.In this study,the MEC for DCM degradation was inoculated with the ac tive sludge enhanced by Methylobacterium rhodesianum H13(strain H13)and then acclimated in the form of a microbial fuel cell(MFC).Both the introduction of strain H13 and the initi ation in MFC form significantly promoted DCM degradation.The degradation kinetics were fitted by the Haldane model,with V_(max),K_(h),K_(i)and v_(max)values of 103.2 mg/L/hr,97.8 mg/L268.3 mg/L and 44.7 mg/L/hr/cm^(2),respectively.The cyclic voltammogram implies that DCM redox reactions became easier with the setup of MEC,and the electrochemical impedance spectrogram shows that the acclimated and enriched microbes reduced the charge transfe resistance from the electrode to the electrolyte.In the biofilm,the dominant genera shifted from Geobacter to Hyphomicrobium in acclimation stages.Moreover,Methylobacterium played an increasingly important role.DCM metabolism mainly occurred through the hydrolytic glutathione S-transferase pathway,given that the gene dcmA was identified rather than the dhlA and P450/MO.The exogenous electrons facilitated the reduction of GSSG,directly o indirectly accelerating the GSH-catalyzed dehalogenation.This study provides support fo the construction of an efficient and stable MEC for DCM removal in water environment.

关键词： Dichloromethane Microbial electrolysis cells Metabolic pathways Electron transfer Degradation kinetics

Paclitaxel-lipid prodrug liposomes for improved drug delivery and breast carcinoma therapy

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2024年第2期35卷 335-340页

作者： Xin Wu Xinmei Chen Xinyu wang Haisheng He jianming Chen Wei Wu Key Laboratory of Smart Drug Delivery of MOE School of PharmacyFudan UniversityShanghai 201203China Department of Pharmacy Fujian University of Traditional Chinese MedicineFuzhou 350122China Shanghai Wei Er Lab Shanghai 201707China Shanghai Skin Disease Hospital Tongji University School of MedicineShanghai 200443China

Paclitaxel(PTX)is widely applied for the treatment of unresectable and metastasis breast carcinoma as well as other cancers,whereas its efficacy is always impeded by poor solubility.Liposomes are one kind of the most successful drug carriers which are capable of solubilizing PTX and improving patients’tolerance owing to excellent biocompatibility and biodegradability.However,poor compatibility between PTX and liposomes compromises the stability,drug loading and anti-tumor capacity of liposomal formulations.To address this issue,three lipids with various chain lengths,namely,myristic acid(MA,14C),palmitic acid(PA,16C)and stearic acid(SA,18C),were conjugated to PTX via ester bonds and the synthesized prodrugs with high lipophilicity were further formulated into liposomes,respectively.All liposomes show high stability and drug loadings,as well as sustained drug release.The chain lengths of lipids are negatively correlated with drug release and enzymatic conversion rates,which further impact the pharmacokinetics,tumor accumulation,and anti-tumor efficacy of liposomal PTX.Neither rapid nor slow drug release facilitates high tumor accumulation as well as anti-tumor efficacy of PTX.Among all liposomes,PTX-PA-loaded liposomes show the longest circulation and highest tumor accumulation of PTX and exert the most potent anti-tumor capacities in vivo,owing to its moderate drug release and enzymatic conversion rate.Witnessing its superior safety,PTX-PA liposomes hold potential for further clinical translation.

关键词： Paclitaxel Lipids Prodrugs Liposomes Drug release Chemotherapy

Advances in the study of protein folding and endoplasmic reticulum-associated degradation in mammal cells

在线全文

学校读者我要写书评

暂无评论

Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2024年第3期25卷 212-232页

作者： Hong CAO Xuchang ZHOU Bowen XU Han HU jianming GUO Yuwei MA Miao wang Nan LI Jun ZOU Department of Sport Rehabilitation Shanghai University of SportShanghai 200438China National Key Laboratory of Immunity and Inflammation Naval Medical UniversityShanghai 200433China

The endoplasmic reticulum is a key site for protein production and quality control.More than one-third of proteins are synthesized and folded into the correct three-dimensional conformation in the endoplasmic reticulum.However,during protein folding,unfolded and/or misfolded proteins are prone to occur,which may lead to endoplasmic reticulum stress.Organisms can monitor the quality of the proteins produced by endoplasmic reticulum quality control(ERQC)and endoplasmic reticulum-associated degradation(ERAD),which maintain endoplasmic reticulum protein homeostasis by degrading abnormally folded proteins.The underlying mechanisms of protein folding and ERAD in mammals have not yet been fully explored.Therefore,this paper reviews the process and function of protein folding and ERAD in mammalian cells,in order to help clinicians better understand the mechanism of ERAD and to provide a scientific reference for the treatment of diseases caused by abnormal ERAD.

关键词： Endoplasmic reticulum-associated degradation(ERAD) Protein folding Ubiquitination Retrotranslocation