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强震区桥梁抗震挡块强度退化模型及其应用

中国公路学报 2024年第7期37卷 179-188页

作者：韦旺邵长江袁得铮王春阳李贞新庄卫林 OKOYA ONOUNGOUA f f 西南交通大学土木工程学院四川成都610031 陆地交通地质灾害防治技术国家工程研究中心四川成都610031 中交公路规划设计院有限公司北京100088

钢筋混凝土抗震挡块作为强震区桥梁的重要受力构件,强震下往往率先发生严重破坏,而现行规范中尚未明确给出挡块的抗震设计方法及其分析模型。为此,在揭示钢筋混凝土抗震挡块斜截面破坏机理的基础上,基于刚体转动平衡方程推导了考虑混凝... 详细信息

钢筋混凝土抗震挡块作为强震区桥梁的重要受力构件,强震下往往率先发生严重破坏,而现行规范中尚未明确给出挡块的抗震设计方法及其分析模型。为此,在揭示钢筋混凝土抗震挡块斜截面破坏机理的基础上,基于刚体转动平衡方程推导了考虑混凝土残余抗拉强度和钢筋变形协调性的3类挡块强度计算公式,并通过能量等效原理建立了挡块强度双折线退化模型。以九度区一座近断层的中小跨径梁桥为例,通过剪切铰模型模拟挡块强度双折线退化,进而探讨挡块承载力下降对桥梁下部结构地震需求的影响。研究结果表明:所提抗震挡块强度计算公式及其强度退化模型能够较为精确地预测挡块的力学特征(计算平均误差小于5%),采用剪切铰模型能够合理地模拟挡块在强震下的损伤行为;强震作用下,不考虑抗震挡块碰撞效应的影响将低估桥梁下部结构的地震需求,会导致不安全的设计结果;而仅考虑挡块刚性碰撞(不考虑挡块承载力下降)则会高估桥梁下部结构的地震需求,容易造成不必要的浪费;抗震挡块不仅起到限制主梁横向位移的作用,而且挡块的损伤一定程度上起到消耗上部结构地震力的作用;考虑所提挡块强度退化后,能准确反映主梁与挡块之间的碰撞力对桥梁下部结构地震需求的影响。所提的挡块强度退化模型及其模拟方法可为九度区中小跨径梁桥的抗震设计提出借鉴。

关键词：桥梁工程强度退化模型剪切破坏机理抗震挡块板式橡胶支座滑动效应九度区

Applying Earth Observation Technologies to Economic Consequence Modeling:A Case Study of COVID‑19 in Los Angeles County,California

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International Journal of Disaster Risk Science 2024年第1期15卷 18-31页

作者： fynnwin Prager Marina T.Mendoza Charles K.Huyck Adam Rose Paul Amyx Gregory Yetman Kristy f.Tiampo California State University Dominguez HillsCarsonCA 90747USA ImageCat Inc.Long BeachCA 90802USA University of Southern California Los AngelesCA 90015USA CIESIN–Center for International Earth Science Information Network Columbia UniversityPalisadesNY 10964USA Cooperative Institute for Research in Environmental Sciences(CIRES) University of Colorado BoulderBoulderCO 80309USA

Earth observation(EO) technologies,such as very high-resolution optical satellite data available from Maxar,can enhance economic consequence modeling of disasters by capturing the fine-grained and real-time behavioral responses of businesses and the *** investigated this unique approach to economic consequence modeling to determine whether crowd-sourced interpretations of EO data can be used to illuminate key economic behavioral responses that could be used for computable general equilibrium modeling of supply chain repercussions and resilience *** applied our methodology to the COVID-19 pandemic experience in Los Angeles County,California as a case *** also proposed a dynamic adjustment approach to account for the changing character of EO through longer-term disasters in the economic modeling *** found that despite limitations,EO data can increase sectoral and temporal resolution,which leads to significant differences from other data sources in terms of direct and total impact *** findings from this analytical approach have important implications for economic consequence modeling of disasters,as well as providing useful information to policymakers and emergency managers,whose goal is to reduce disaster costs and to improve economic resilience.

关键词： Computable general equilibrium models COVID-19 Disaster economic impacts Earth observation Economic consequence analysis Los Angeles County

Retreived bacteria from Noctiluca miliaris (green) bloom of the northeastern Arabian Sea

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Chinese Journal of Oceanology and Limnology 2013年第1期31卷 10-20页

作者： BASU Subhajit MATONDKAR SG Prabhu furtado Irene Department of Microbiology Goa University National Institute of Oceanography (CSIR-India)

In recent years, seasonal blooms of the dinoflagellate Noctiluca miliaris have appeared in the open-waters of the northern Arabian Sea （NAS）. This study provides the first characterization of bacteria from a seasonal bloom of green Noctiluca ofNAS （20°N-17°N and 64°E-70°E）, during the spring-inter-monsoon cruise ofSagar Sampada 253, in March 2007. Bacterial growth as assessed by most-probable number （MPN） and plate counts, revealed ＇variable-physiotypes＇ over a wide range of salinities （0%-25% w/v NaC1）, pH levels （5-8.5）, and organic nutrient strengths, in comparison to non-bloom waters. MPN indices of bacteria in surface waters of bloom stations ＊DWK and ＊PRB, corresponded to （3.08-4.41）×103 cells/mL at 3.5% NaC1 （w/v）, and （2.82-9.49）× 102 cells/mL at 25% （w/v） NaC1 in tryptone-yeast extract broth （TYE）. Plate counts were （1.12-4） × 106 CfU/mL at 0% （w/v） NaC1, （1.28-3.9） × 106 CfU/mL at 3.5% （w/v） NaC1, and （0.4- 7）×104 CfU/mL at 25% NaC1 （w/v） on TYE. One-tenth-strength Zobell＇s gave （0.6-3.74）× 105 CfU/mL at pH 5 to （3.58-7.5）× 105 CfU/mL at pH 8.5. These bacteria were identified to the genera Bacillus, Cellulomonas, Staphylococcus, Planococcus, Dietzia, Diergibacillus, Micrococcus, Sporosarcinae, Leucobacter, and Halomonas. The identity of three strains （GUfBSS253N2, GUfBSS253N30, and GUfBSS253N84） was confirmed through 16S rDNA sequence homology as Bacillus cohnii, Bacillusflexus, and Bacillus cereus. The -2-3-fold higher plate counts of culturable bacteria from the open-waters of the NAS indicate that these bacteria could critically determine the biogeochemical dynamics of the bloom and its milieu. The role of these bacteria in sustaining/terminating the bloom is under evaluation.

关键词： northeastern Arabian Sea (NAS) green Noctiluca bloom retrievable bacteria

Heat and mass transfer of a circular porous moist object located in a triangular shaped vented cavity

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Journal of Central South University 2024年第6期31卷 1956-1972页

作者： SELIMEfENDIGIL fatih OZCAN COBAN Seda OZTOP Hakan f Department of Mechanical Engineering College of EngineeringKing Faisal UniversityAl Ahsa 31982Saudi Arabia Department of Mechanical Engineering Manisa Celal Bayar UniversityManisa 45140Turkey Department of Mechanical Engineering Technology FacultyFırat UniversityElazığTurkey

Heat and mass transfer of a circular-shaped porous moist object inside a two-dimensional triangle cavity is investigated by using finite element *** porous object is considered to be a moist food sample,located in the middle of the cavity with inlet and outlet ports with different configurations of inlet/outlet *** drying performance is numerically assessed for different values of Reynolds numbers(between 50 and 250),dry air inlet temperature(between 40 and 80℃)and different locations of the *** is observed that changing the port locations has significant impacts on the flow recirculaitons inside the triangular chamber while convective drying performance is highly *** moisture content reduces with longer time and for higher Reynolds number(Re)*** P4 where inlet and outlet ports are in the middle of the walls provides the most effective configuration in terms of convective drying performance while the worst case is seen for P1 case where inlet and outlet are closer to the corners of the *** is a 192% difference between the moisture reduction of these two cases at Re=250,T=80℃ and t=120 min.

关键词： convective drying porous domain cavity flow inlet/exit port finite element method

Reviewing 40 years of artificial intelligence applied to power systems-A taxonomic perspective

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Energy and AI 2024年第1期15卷 136-150页

作者： f.Heymann H.Quest T.Lopez Garcia C.Ballif M.Galus Swiss federal Office for Energy(SfOE) Section Geoinformation and Digital InnovationIttigenSwitzerland Ecole Polytechnique fédérale de Lausanne(EPfL) Photovoltaics and Thin-Film Electronics Laboratory(PV-LAB)Institute of Electrical and Micro Engineering(IEM)NeuchâtelSwitzerland 3S Swiss Solar Solutions AG ThunSwitzerland Swiss Center for Electronics and Microtechnology(CSEM) Sustainable Energy CenterNeuchâtelSwitzerland Digital Energy and Electric Power Lucerne University of Applied Sciences and ArtsLucerneSwitzerland

Artificial intelligence(AI)as a multi-purpose technology is gaining increased attention and is now widely used across all sectors of the *** growing complexity of planning and operating power systems makes AI extremely valuable for the power *** now,there has been a lack of clarity regarding the specific points along the power system supply chain where AI applications demonstrate significant value,as well as which AI domains are best suited for such *** study employs an AI taxonomy and automated web search to qualitatively and quantitatively unveil the biggest potentials of AI in the power *** analysis,based on a review of 258’919 publications between 1982 and 2022,reveals where AI applications are particularly *** consider six AI domains(reasoning,planning,learning,communication,perception,integration&interaction)and 19 use cases from the power supply chain(i.e.,generation,transmission networks,distribution networks,isolated grids/microgrids,market operations and retail).Our findings indicate that,as of now,the focus is predominantly on AI applications in power retail(55%),transmission(14%)and generation(13%).Most analyzed works describe applications built on algorithms of the AI domains“learning”(45%)and“planning”(14%).Results also suggest that the current definition of AI domains is ambiguous,and they highlight missing information on the actual use and successful implementation of AI in power system use cases.

关键词： Artificial intelligence Power systems Electricity Taxonomy Policy

A new technique for fault diagnosis in transformer insulating oil based on infrared spectroscopy measurements

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High Voltage 2024年第2期9卷 319-335页

作者： Mohamed M.f.Darwish Mohamed H.A.Hassan Nagat M.K.Abdel-Gawad Matti Lehtonen Diaa-Eldin A.Mansour Department of Electrical Engineering Faculty of Engineering at ShoubraBenha UniversityCairoEgypt Department of Electrical Engineering and Automation School of Electrical EngineeringAalto UniversityEspooFinland Department of Electrical Power Engineering Egypt-Japan University of Science and Technology(E-JUST)New Borg El-Arab CityEgypt Department of Electrical Power and Machines Engineering Faculty of EngineeringTanta UniversityTantaEgypt

Condition monitoring of the insulating system within power transformers has a massive importance according to the electrical *** gas analysis(DGA)is frequently used for this ***,DGA lacks the necessary level of accuracy to identify all equipment faults,particularly in their initial stages of ***,it does not have the capability for real-time monitoring and relies on manual sampling and laboratory testing,causing potential delays in fault ***,the interpretation of DGA data necessitates specialised expertise,which may pose difficulties for smaller entities that have limited access to ***,the contribution of this research is to use infrared spectroscopy measurements as a new effective technique substituting the DGA method for fault diagnosis in insulating *** inception faults that were considered in this study were the electrical fault(discharges of high energy)and the thermal fault(300°Cfted especially for serving the simulation processes inside the laboratory for both types of inception ***,six samples of pure paraffinic mineral oil were taken to be degraded in the *** that,all of them besides another sample that were not subjected to any kind of faults were taken to be examined by fourier transform infrared(fTIR)spectroscopy to obtain an overview of the oil's behaviour in each fault *** that,the fTIR analysis was initially verified utilising the DGA ***,for further affirmation,the dielectric dissipation factor(DDf)for all samples was *** the final analysis,the verification tests provide experimental evidence about the outperformance of this new optical technique in detecting the transformer's inception faults in addition to proving its potential for being a superior alternative to the well-known traditional diagnostic techniques.

关键词： fault diagnosis spectroscopy

Use of Targeted Orographic Smoothing in Very High Resolution Simulations of a Downslope Windstorm and Rotor in a Sub-tropical Highland Location

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Advances in Atmospheric Sciences 2023年第11期40卷 2043-2062页

作者： Peter SHERIDAN Anlun XU Jian LI Kalli furtado Met Office ExeterEX13PBUK Dali National Climate Observatory Dali 671003China State Key Laboratory of Severe Weather and Institute of Tibetan Plateau Meteorology Chinese Academy of Meteorological SciencesBeijing 100081China National Environment Agency Singapore

Nested simulations of a downslope windstorm over Cangshan mountain,Yunnan,China,have been used to demonstrate a method of topographic smoothing that preserves a relatively large amount of terrain detail compared to typical smoothing procedures required for models with terrain-following grids to run *** simulations were carried out using the Met Office Unified Model(MetUM)to investigate downslope *** smoothing method seamlessly blends two terrain datasets to which uniform smoothing has been applied—one with a minimum of smoothing,the other smoothed more heavily to remove gradients that would cause model *** latter dataset dominates the blend where the steepest slopes exist,but this is localised and recedes outside these *** a result,increased detail is starkly apparent in depictions of flow simulated using the blend,compared to one using the default *** includes qualitative flow details that were absent in the latter,such as narrow shooting flows emerging from roughly 1-2 km wide leeside *** separation is more common due to steeper lee *** use of targeted smoothing also results in increased lee side temporal variability at a given point during the windstorm,including over flat ***-/high-pass filtering of the wind perturbation field reveals that relative spatial variability above 30 km in scale(reflecting the background flow)is similar whether or not targeting is *** this scale,when smoothing is targeted,relative flow variability decreases at the larger scales,and increases at lower *** seems linked to fast smaller scale flows disturbing more coherent flows(notably an along-valley current over Erhai Lake).Spatial variability of winds in the model is unsurprisingly weaker at key times than is observed across a local network sampling mesoscale variation,but results are compromised due to relatively few observation locations sampling the *** when targeted smoothing is applied doe

关键词： lee wave turbulence mountain Tibetan Plateau aviation flow separation foehn complex terrain

Insulin therapy in type 2 diabetes: Insights into clinical efficacy, patient-reported outcomes, and adherence challenges

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World Journal of Diabetes 2024年第5期15卷 828-852页

作者： Mahmoud Emad-Eldin Gehan f Balata Eman A Elshorbagy Mona S Hamed Mohamed S Attia Department of Pharmacy Practice Faculty of PharmacyZagazig UniversityZagazig HFQM+872Al-Sharqia GovernorateEgypt Department of Pharmacy Practice Faculty of PharmacyHeliopolis UniversityCairo 44519Egypt Department of Pharmaceutics Faculty of PharmacyZagazig UniversityZagazig 44519Al-Sharqia GovernorateEgypt Department of Internal Medicine Faculty of MedicineZagazig UniversityZagazig 44519Al-Sharqia GovernorateEgypt Department of Community at faculty of Medicine Zagazig UniversityZagazig 44519Al-Sharqia GovernorateEgypt

Insulin therapy plays a crucial role in the management of type 2 diabetes as the disease *** the past century,insulin formulations have undergone significant modifications and bioengineering,resulting in a diverse range of available insulin *** products show distinct pharmacokinetic and pharmacodynamic ***,various insulin regimens have em-erged for the management of type 2 diabetes,including premixed formulations and combinations of basal and bolus *** utilization of different insulin regimens yields disparate clinical outcomes,adverse events,and,notably,patient-reported outcomes(PROs).PROs provide valuable insights from the patient’s perspective,serving as a valuable mine of information for enhancing healthcare and informing clinical *** to insulin therapy,a critical patient-reported outcome,significantly affects clinical outcomes and is influenced by multiple *** review provides insights into the clinical effectiveness of various insulin preparations,PROs,and factors impacting insulin therapy adherence,with the aim of enhancing healthcare practices and informing clinical decisions for individuals with type 2 diabetes.

关键词： Adherence Diabetes Insulin Patient-reported outcomes Pharmacokinetic Pharmacodynamic

The Importance of Posterior Tibial Slope in TKR: Pre and Post-Operative Measurements in United States Osteoarthritic Patients

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Open Journal of Orthopedics 2024年第8期14卷 374-379页

作者： frederick f. Buechel Sr frederick f. Buechel Jr Rutgers New Jersey Medical School Department of Orthopaedic Surgery Newark USA Lenox Hill Hospital Department of Orthopaedic Surgery New York USA

Background: Sagittal plane placement of the tibial component in total knee replacement (TKR) has important implications for maximizing the range of flexion motion, allowing collateral ligaments to function more normally, as well as providing ideal compressive loading on the tibial bone-prosthesis interface. This study attempts to quantify the normal posterior tibial slope (PTS) angle pre-operatively and post-operatively in osteoarthritic patients after using a conventional extramedullary tibial resection guide to assess its effectiveness. Methods: forty-nine primary cementless total knee replacements in 34 osteoarthritic patients were measured radiographically pre-operatively and one year post-operatively to determine the PTS and its effect on range of motion. Lateral X-rays, using the anterior cortical line of the tibia, were employed for all measurements. Results: Pre-operative PTS measured 11.83˚ (range 5˚ - 18˚), while post-operative PTS of implanted tibial components measured 11.30o (range 4˚ - 18˚). The pre-operative range of motion of 112˚ (range 30˚ to 135˚) was improved to 119˚ (range 90˚ to 135˚) post-operatively after 1 year. Conclusions: Anterior tibial shaft referencing using a conventional extramedullary tibial resection guide provides an easy and convenient method for reproducing the anatomical PTS during TKR. This methodology provided improvement in average range of motion from 112˚ pre-operatively to 119˚ post-operatively at one year.

关键词： Posterior Tibial Slope Posterior Tibial Inclination Extramedullary Tibial Resection Guide Total Knee Alignment