检索结果-南通市图书馆

Modal Parameter Identification Method of Jacket Platform Structure Based on AFDD and Optimized FBFFT

在线全文

学校读者我要写书评

暂无评论

China Ocean Engineering 2023年第3期37卷 393-407页

作者： LENG Jian-cheng MA Jin-yong FAN Zong-heng QIAN Wan-dong feng hui-yu School of Mechanical Science and Engineering Northeast Petroleum UniversityDaqing 163318China

Offshore platforms are susceptible to structural damage due to prolonged exposure to random loads,such as wind,waves,and *** is particularly true for platforms that have been in service for an extended *** the modal parameters of offshore platforms is crucial for damage diagno sis,as it serves as a prerequisite and foundation for the ***,it holds great significance to prioritize the identification of these *** at the shortcomings of the traditional Fast Bayesian Fast Fourier Transform(FBFFT) method,this paper proposes a modal parameter identification method based on Automatic Frequency Domain Decomposition(AFDD) and optimized *** introducing the AFDD method and Powell optimization algorithm,this method can automatically identify the initial value of natural frequency and solve the objective function efficiently and *** order to verify the feasibility and effectiveness of the proposed method,it is used to identify the modal parameters of the IASC-ASCE benchmark model and the j acket platform structure model,and the Most Probable Value(MPV) of the modal parameters and their respective posterior uncertainties are successfully *** identification results of the IASC-ASCE benc hmark model are compared with the identification re sults of the MODE-ID method,which verifies the effectivene ss and accuracy of the proposed method for identifying modal *** provides a simple and feasible method for quantifying the influence of uncertain factors such as environmental parameters on the identification results,and also provide s a reference for modal parameter identification of other large structures.

关键词： jacket platform uncertain modal parameter identification FBFFT method environmental excitation AFDD method Powell optimization

A real-time intelligent lithology identification method based on a dynamic felling strategy weighted random forest algorithm

在线全文

学校读者我要写书评

暂无评论

Petroleum Science 2024年第2期21卷 1135-1148页

作者： Tie Yan Rui Xu Shi-hui Sun Zhao-Kai Hou Jin-yu feng School of Petroleum Engineering Northeast Petroleum UniversityDaqing163318HeilongjiangChina Sanya Offshore Oil&Gas Research Institute Northeast Petroleum UniversitySanya572025HainanChina

Real-time intelligent lithology identification while drilling is vital to realizing downhole closed-loop drilling. The complex and changeable geological environment in the drilling makes lithology identification face many challenges. This paper studies the problems of difficult feature information extraction,low precision of thin-layer identification and limited applicability of the model in intelligent lithologic identification. The author tries to improve the comprehensive performance of the lithology identification model from three aspects: data feature extraction, class balance, and model design. A new real-time intelligent lithology identification model of dynamic felling strategy weighted random forest algorithm(DFW-RF) is proposed. According to the feature selection results, gamma ray and 2 MHz phase resistivity are the logging while drilling(LWD) parameters that significantly influence lithology identification. The comprehensive performance of the DFW-RF lithology identification model has been verified in the application of 3 wells in different areas. By comparing the prediction results of five typical lithology identification algorithms, the DFW-RF model has a higher lithology identification accuracy rate and F1 score. This model improves the identification accuracy of thin-layer lithology and is effective and feasible in different geological environments. The DFW-RF model plays a truly efficient role in the realtime intelligent identification of lithologic information in closed-loop drilling and has greater applicability, which is worthy of being widely used in logging interpretation.

关键词： Intelligent drilling Closed-loop drilling Lithology identification Random forest algorithm Feature extraction

Co-Harvest Phase-Change Enthalpy and Isomerization Energy for High-Energy Heat Output by Controlling Crystallization of Alkyl-Grafted Azobenzene Molecules

在线全文

学校读者我要写书评

暂无评论

Energy & Environmental Materials 2024年第3期7卷 419-428页

作者： Jian Gao Yiyu feng Wenyu Fang hui Wang Jing Ge Xiaoyu Yang huitao yu Mengmeng Qin Wei feng School of Materials Science and Engineering Tianjin University Key Laboratory of Materials Processing and Mold Ministry of EducationZhengzhou University

Photoisomerization-induced phase change are important for co-harvesting the latent heat and isomerization energy of azobenzene *** optimizing heat output and energy delivery at alternating temperatures are challenging because of the differences in crystallizability and *** article reports two series of asymmetrically alkylgrafted azobenzene （Azo-g）,with and without a methyl group,that have an optically triggered phase *** exothermic modes were designed to utilize crystallization enthalpy （ΔHc） and photothermal （isomerization）energy （ΔHp） at different temperatures determined by the ***-g has high heat output (275-303 J g-1) by synchronously releasingΔHcandΔHpover a wide temperature range （-79℃to 25℃）.We fabricated a new distributed energy utilization and delivery system to realize a temperature increase of 6.6℃at a temperature of-8℃.The findings offer insight into selective utilization of latent heat and isomerization energy by molecular optimization of crystallization and isomerization processes.

关键词： crystallizability distributed energy utilization system energy density exothermic modes isomerization

重症肌无力危象前状态管理专家共识(2024)

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

中国临床神经科学 2024年第3期32卷 241-251页

作者：罗苏珊周昊岳耀先卜碧涛常婷邓晖段瑞生笪宇威冯慧宇管宇宙王玉鸽杨春生张华周红雨赵重波杨欢复旦大学附属华山医院神经内科国家神经疾病医学中心上海200040 中南大学湘雅医院神经内科长沙410008 山东大学齐鲁医院(青岛)神经内科青岛266035 华中科技大学同济医学院附属同济医院神经内科武汉430030 空军军医大学第二附属医院神经内科西安710038 吉林大学白求恩第一医院神经内科长春130021 山东第一医科大学第一附属医院神经内科济南250014 首都医科大学宣武医院神经内科北京100053 中山大学附属第一医院神经内科广州510080 中国医学科学院北京协和医院神经内科北京100730 中山大学附属第三医院神经内科广州510635 天津医科大学总医院神经内科天津300052 北京医院神经内科北京100730 四川大学华西医院神经内科成都610041 中国罕见病联盟/北京罕见病诊疗与保障学会重症肌无力协作组北京100022

重症肌无力(MG)是一种自身免疫性神经-肌肉接头疾病,肌无力危象(MC)是MG患者的最严重状态,显著增加患者死亡风险和疾病负担,如能及时识别和干预MG危象前状态,阻止疾病向MC进展,其临床意义重大。然而MG危象前状态的诊断尚无统一标准,对... 详细信息

重症肌无力(MG)是一种自身免疫性神经-肌肉接头疾病,肌无力危象(MC)是MG患者的最严重状态,显著增加患者死亡风险和疾病负担,如能及时识别和干预MG危象前状态,阻止疾病向MC进展,其临床意义重大。然而MG危象前状态的诊断尚无统一标准,对其治疗管理亦缺乏高级别证据。为此,中国MG协作组专家基于新近研究结果和临床实践经验,经过反复讨论,围绕MG危象前状态的早期识别、诊断标准、治疗干预及随访管理等形成共识,以期为临床改善MG危象前状态的管理及预后提供参考。

关键词：重症肌无力肌无力危象危象前状态管理共识

Jejunal sarcomatoid carcinoma:A case report and review of literature

在线全文

学校读者我要写书评

暂无评论

World Journal of Gastrointestinal Oncology 2024年第8期16卷 3723-3731页

作者： Qian feng Wei yu Jing-hui feng Qiao Huang Gui-Xiang Xiao The First College of Clinical Medical Science China Three Gorges UniversityYichang 443000Hubei ProvinceChina Department of Oncology Yichang Central People's HospitalYichang 443000Hubei ProvinceChina Institute of Pathology Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430022Hubei ProvinceChina

BACKGROUND Sarcomatoid carcinoma(SCA)of the jejunum is a rare and aggressive neoplasm affecting the smooth muscle cells of the *** study presents a recent case of jejunal SCA,detailing its diagnosis and treatment,thereby providing a reference for clinical *** SUMMARY A 65-year-old male presented to Yichang Central People's Hospital with a chief complaint of hemorrhoids.A computed tomography(CT)scan incidentally revealed multiple abnormal signals in the *** positron emission tomography/CT at Wuhan Union Hospital indicated malignant tumor progression,with a primary duodenal tumor and multiple metastases in the upper left ***,a large tumor was identified on the *** and immunohistochemical analyses of the resected specimen confirmed the diagnosis of jejunal *** patient received a combination therapy of sintilimab,nanoparticle albumin-bound paclitaxel,and ***-up imaging demonstrated significant reduction of hepatic and peritoneal *** patient has remained stable for over one year *** This case suggests that chemotherapy,immunotherapy,plus targeted therapy may represent an optimal treatment for intestinal SCA,meriting further investigation.

关键词： Jejunal sarcomatoid carcinoma Targeted therapy Immunotherapy Chemotherapy Case report

From non-carbon host toward carbon-free lithium-sulfur batteries

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

Nano Research 2024年第3期17卷 1337-1365页

作者： Yanqi feng hui Liu Qiongqiong Lu School of Materials Science and Engineering Shaanxi Key Laboratory of Green Preparation and Functionalization for Inorganic MaterialsShaanxi University of Science and TechnologyXi’an 710021China Institute of Materials Henan Key Laboratory of Advanced Conductor MaterialsHenan Academy of SciencesZhengzhou 450046China Leibniz Institute for Solid State and Materials Research(IFW)Dresden e.V. Helmholtzstraβe 2001069 DresdenGermany School of Materials&Environment Engineering Chengdu Technological UniversityChengdu 611730China

Lithium-sulfur(Li-S)batteries with advantages of high energy densities(2600 Wh·kg^(-1)/2800 Wh·L^(-1))and sulfur abundance are regarded as promising candidates for next-generation high-energy ***,the conventional carbon host used in sulfur cathodes suffers from poor chemical adsorption towards Li-polysulfides(LPS)in liquid electrolyte and sluggish redox kinetics,leading to low capacity and rate ***,carbon host used in Li metal anode with the intrinsic property of poor lithiophilicity and high Li-nucleation barrier gives rise to uncontrollable dendrite growth and further battery ***,non-carbon hosts with chemical adsorption toward LPS and catalytic activity for accelerating LPS redox conversion as well as lithiophilic property for guiding uniform Li deposition are proposed and demonstrated a high efficiency in both sulfur cathodes and Li metal *** this review,the principle and challenges of Li-S batteries are first presented,then recent work using non-carbon hosts in Li-S batteries is summarized comprehensively,and the mechanism of non-carbon host in improving sulfur utilization and stabilizing Li metal anode is discussed in ***,remaining challenges and outlook on the implementation of non-carbon host for practical carbon-free Li-S batteries are also provided.

关键词： sulfur cathode Li metal anode polysulfides adsorption catalytic effect Li dendrite carbon-free lithium-sulfur batteries

Corrugated Graphene Paper Reinforced Silicone Resin Composite for Efficient Interface Thermal Management

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

Chinese Journal of Polymer Science 2024年第7期42卷 1002-1014,I0010页

作者： Bo-Wen Wang Heng Zhang Qing-Xia He hui-Tao yu Meng-Meng Qin Wei feng Tianjin Key Laboratory of Composite and Functional Materials School of Materials Science and EngineeringTianjin UniversityTianjin300350China International Engineering Institute Tianjin UniversityTianjin300350China

With the rapid development of high-power-density electronic devices,interface thermal resistance has become a critical barrier for effective heat management in high-performance electronic ***,there is an urgent demand for advanced thermal interface materials(TIMs)with high cross-plane thermal conductivity and excellent compressibility to withstand increasingly complex operating *** achieve this aim,a promising strategy involves vertically arranging highly thermoconductive graphene on ***,with the currently available methods,achieving a balance between low interfacial thermal resistance,bidirectional high thermal conductivity,and large-scale production is ***,we prepared a graphene framework with continuous filler structures in in-plane and cross-plane directions by bonding corrugated graphene to planar graphene *** interface interaction between the graphene paper framework and polymer matrix was enhanced via surface functionalization to reduce the interface thermal *** resulting three-dimensional thermal framework endows the polymer composite material with a cross-plane thermal conductivity of 14.4 W·m^(-1)·K^(-1)and in-plane thermal conductivity of 130W·m^(-1)·K^(-1)when the thermal filler loading is 10.1 wt%,with a thermal conductivity enhancement per 1 wt%filler loading of 831%,outperforming various graphene structures as *** its high thermal conductivity,low contact thermal resistance,and low compressive modulus,the developed highly thermoconductive composite material demonstrates superior performance in TIM testing compared with TFLEX-700,an advanced commercial TIM,effectively solving the interfacial heat transfer issues in electronic *** novel filler structure framework also provides a solution for achieving a balance between efficient thermal management and ease of processing.

关键词： Graphene paper Vertically aligned structure Cross-plane thermal conductivity Low compressive modulus Thermal interface material

Derivation of Expanded Isospectral-Nonisospectral Integrable Hierarchies via the Column-vector Loop Algebra

在线全文

学校读者我要写书评

暂无评论

Acta Mathematicae Applicatae Sinica 2024年第3期40卷 778-800页

作者： Hai-feng WANG yu-feng ZHANG School of Science Jimei UniversityXiamen 361021China School of Mathematics China University of Mining and TechnologyXuzhou 221116China

A scheme for generating nonisospectral integrable hierarchies is *** on the method,we deduce a nonisospectral hierarchy of soliton equations by considering a linear spectral *** follows that the corresponding expanded isospectral and nonisospectral integrable hierarchies are deduced based on a 6 dimensional complex linear space ■.By reducing these integrable hierarchies,we obtain the expanded isospectral and nonisospectral derivative nonlinear Schr?dinger *** using the trace identity,the biHamiltonian structure of these two hierarchies are also ***,some symmetries and conserved quantities of the resulting hierarchy are discussed.

关键词： expanded isospectral-nonisospectral integrable hierarchies column-vector loop algebra bi-Hamiltonian structure symmetry

Higher-order expansions of powered extremes of logarithmic general error distribution

在线全文

学校读者我要写书评

暂无评论

Applied Mathematics(A Journal of Chinese Universities) 2024年第1期39卷 47-54页

作者： TAN Xiao-feng LI Li-hui School of Mathematics and Statistics Southwest UniversityChongqing 400715China

In this paper,Let M_(n)denote the maximum of logarithmic general error distribution with parameter v≥***-order expansions for distributions of powered extremes M_(n)^(p)are derived under an optimal choice of normalizing *** is shown that M_(n)^(p),when v=1,converges to the Frechet extreme value distribution at the rate of 1/n,and if v>1 then M_(n)^(p)converges to the Gumbel extreme value distribution at the rate of(loglogn)^(2)=(log n)^(1-1/v).

关键词： logarithmic general error distribution convergence rate higher-order expansion powered ex-treme