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Probabilistic analysis of ultimate seismic bearing capacity of strip foundations

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journal of Rock Mechanics and Geotechnical Engineering 2018年第4期10卷 717-724页

作者： Adam Hamrouni Badreddine Sbartai daniel Dias Laboratory InfraRes Mohammed Cherif Messaadia UniversitySouk-AhrasAlgeria Department of Civil Engineering Badji Mokhtar-Annaba UniversityAnnabaAlgeria Laboratory LMGHU Skikda UniversitySkikdaAlgeria School of Automotive and Transportation Engineering Hefei University of TechnologyHefei230009China Grenoble Alpes University Laboratory 3SRGrenobleFrance

This paper presents a reliability analysis of the pseudo-static seismic bearing capacity of a strip foundation using the limit equilibrium theory. The first-order reliability method(FORM) is employed to calculate the reliability index. The response surface methodology(RSM) is used to assess the Hasofer e Lind reliability index and then it is optimized using a genetic algorithm(GA). The random variables used are the soil shear strength parameters and the seismic coefficients(khand kv). Two assumptions(normal and non-normal distribution) are used for the random variables. The assumption of uncorrelated variables was found to be conservative in comparison to that of negatively correlated soil shear strength parameters. The assumption of non-normal distribution for the random variables can induce a negative effect on the reliability index of the practical range of the seismic bearing capacity.

关键词： Strip foundations Seismic bearing capacity First-order reliability method (FORM) Response surface methodology (RSM) Reliability Genetic algorithm (GA)

Analysis of Autopilot Disengagements Occurring During Autonomous Vehicle Testing

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IEEE/CAA journal of Automatica Sinica 2018年第1期5卷 58-68页

作者： Chen Lv Dongpu Cao Yifan Zhao daniel j. Auger Mark Sullman Huaji Wang Laura Millen Dutka Lee Skrypchuk Alexandros Mouzakitis School of Aerospace Transport and Manufacturing Cranfield University Cranfield Bedford MK430AL UK jaguar Land Rover Coventry CV3 4LF UK IEEE

In present-day highly-automated vehicles, there are occasions when the driving system disengages and the human driver is required to take-over. This is of great importance to a vehicle's safety and ride comfort. In the U.S state of California, the Autonomous Vehicle Testing Regulations require every manufacturer testing autonomous vehicles on public roads to submit an annual report summarizing the disengagements of the technology experienced during testing. On 1 january 2016,seven manufacturers submitted their first disengagement reports:Bosch, Delphi, Google, Nissan, Mercedes-Benz, Volkswagen, and Tesla Motors. This work analyses the data from these disengagement reports with the aim of gaining abetter understanding of the situations in which a driver is required to takeover, as this is potentially useful in improving the Society of Automotive Engineers(SAE) Level 2 and Level 3 automation *** events from testing are classified into different groups based on attributes and the causes of disengagement are investigated and compared in detail. The mechanisms and time taken for take-over transition occurred in disengagements are studied. Finally, recommendations for OEMs, manufacturers, and government organizations are also discussed.

关键词： Automated vehicle Disengagement humanvehicle interactions take-over operation vehicle testing

In vitro and in vivo cytochrome P450 3A enzyme inhibition by Aframomum melengueta and Dennettia tripetala extracts

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Asian Pacific journal of Tropical Medicine 2017年第6期10卷 645-650页

作者： Sunday O.Nduka Mathew j.Okonta daniel L.Ajaghaku Chinwe V.Ukwe Department of Clinical Pharmacy and Pharmacy Management Nnamdi Azikiwe UniversityAwkaAnambra StateNigeria Department of Clinical Pharmacy and Pharmacy Management University of NigeriaNsukkaEnugu StateNigeria Department of Pharmacology and Toxicology Nnamdi Azikiwe UniversityAwkaAnambra StateNigeria

Objective: To evaluate the in vitro and in vivo inhibitory effects of two commonly used herbs, Aframomum melengueta(A. melengueta) and Dennettia tripetala(D. tripetala) on CYP 3A enzymes. Methods: In vitro inhibition of the enzymes were assessed with microsomes extracted from female albino rats using erythromycin-N-demethylation assay(EMND) method while their in vivo effects were measured by estimating simvastatin plasma concentrations in rats. Pharmacokinetic parameters were determined using non-compartmental anaysis as implemented in Win Nonlin pharmacokinetic program. Results: EMND assay with intestinal microsomes indicated that aqueous extracts of D. tripetala and A. melengueta significantly(P < 0.05) inhibited intestinal CYP 3A activity at both 50 μg and 100 μg concentrations. Petroleum ether extract of D. tripetala and ethanol extracts of A. melengueta inhibited intestinal CYP3 A activity at 100 μg but not at 50 μg concentrations. All the extracts showed an in vitrodose dependent CYP 3A inhibition with liver microsomes. In vivo analysis showed that pretreatment with the extracts enhanced systemic absorption of simvastatin with reductions in metabolizing enzymes activity as indicated in significant increases in maximal concentration, area under curve, area under moment curve and mean resident time of simvastatin(P < 0.05). Conclusions: Herbal preparations containing these plants' extracts should be used with caution especially in patients on CYP450 3A substrate medications.

关键词： Cytochrome P450 enzymes CYP 3A Enzyme inhibition Herbal extracts

Carbon nanotube and conducting polymer composites for supercapacitors

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Progress in Natural Science:Materials International 2008年第7期18卷 777-788页

作者： daniel jewell George Z. Chen School of Chemical and Environmental and Mining Engineering University of Nottingham University ParkNottingham NG7 2RD UK

Composites of carbon nanotubes and conducting polymers can be prepared via chemical synthesis, electrochemical deposition on pre- formed carbon nanotube electrodes, or by electrochemical co-deposition. The composites combine the large pseudocapacitance of the conducting polymers with the fast charging/discharging double-layer capacitance and excellent mechanical properties of the carbon nanotubes. The electrochemically co-deposited composites are the most homogeneous and show an unusual interaction between the polymer and nanotubes, giving rise to a strengthened electron delocalisation and conjugation along the polymer chains. As a result they exhibit excellent electrochemical charge storage properties and fast charge/discharge switching, making them promising electrode mate- rials for high power supercapacitors.

关键词： Supercapacitor Carbon nanotube Conducting polymer

Surgery in the age of biologics

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Gastroenterology Report 2019年第2期7卷 77-90,I0001页

作者： daniel j.Wong Eve M.Roth joseph D.Feuerstein Vitaliy Y.Poylin Department of Surgery Division of Colon&Rectum SurgeryBeth Israel Deaconess Medical CenterHarvard Medical SchoolBostonMassachusettsUSA Department of Medicine Division of GastroenterologyBeth Israel Deaconess Medical CenterHarvard Medical SchoolBostonMassachusettsUSA

Since the introduction of the first anti-tumor necrosis factor antibodies in the late 1990s,biologic therapy has revolutionized the medical treatment of patients with inflammatory bowel disease(IBD).Nevertheless,surgery continues to play a significant role in treating IBD *** of intestinal resection in patients with Crohn’s disease or colectomy in ulcerative colitis are reducing but not substantially over the long *** increasing variety of biologic medications are now available to treat IBD patients in various clinical ***,a number of questions persist about how biologic medications affect the need for surgery and overall course in IBD *** the trend for earlier and more frequent use of biologic medications in IBD patients,a working knowledge of the effects of these medications on surgical decision-making and outcomes is essential for the practicing colorectal surgeon and *** review seeks to summarize the relevant literature surrounding biologic use and IBD surgery with a focus on the effect of biologics on the frequency,type and complications of surgery in this‘age of biologics’.

关键词： Biologics inflammatory bowel disease surgery review

Reliability analysis of shallow tunnels using the response surface methodology

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Underground Space 2017年第4期2卷 246-258页

作者： Adam Hamrouni daniel Dias Badreddine Sbartai Grenoble Alpes Uniersity Laboratory 3SRGrenobleFrance Mohamnmed Cherif Messaadia University Laboratory InfraResSouk-AhrasAlgeria Department of Civil Engineering University Bdji Mokhtar Annaba&LMGHU LaboratoryUniversity 204out1955 SkikdaAlgeria

A probabilistic study of a circular tunnel excavated in a soil mass using the response surface methodology(RSM)is presented.A deterministic model based on two-dimensional numerical simulations in a transversal section is used,and the serviceability limit state(SLS)is considered in the *** model permits the surface settlement curve and the bending moment on the tunnel lining to be *** the soil parameters are considered as random ***ﬁrst-order reliability method(FORM)and the response surface methodology(RSM)are utilized for the assessment of the Hasofer-Lind reliability index(bHL)optimized by the use of a genetic algorithm(GA).Two assumptions(normal and non-normal distribution)were used for the random *** comparison analysis considering a correlation between the friction angle and the cohesion indicates that the results are conservative if a negative correlation among strength parameters is not taken into *** assumption of a non-normal distribution for the random variables has an important effect on the reliability index for the practical range of values of surface settlements.

关键词： Tunnel Convergence-conﬁnement method FORM Response surface reliability Limit states Approximate performance function Genetic algorithm

Analysis of the corrosion performance of binder jet additive manufactured magnesium alloys for biomedical applications

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journal of Magnesium and Alloys 2022年第5期10卷 1296-1310页

作者： Kai Xiang Kuah daniel j.Blackwood Wee Kit Ong Mojtaba Salehi Hang Li Seet Mui Ling Sharon Nai Sudesh Wijesinghe Department of Materials Science&Engineering National University of Singapore9 Engineering Drive 1117575 Singapore Reliability and Characterisation Unit Singapore Institute of Manufacturing Technology(SIMTech)Agency forScienceTechnology and Research(A^(∗)STAR)73 Nanyang Drive637662 Singapore Additive Manufacturing Group Singapore Institute of Manufacturing Technology(SIMTech)Agency forScienceTechnology and Research(A^(∗)STAR)73 Nanyang Drive637662 Singapore

Binder jet printing(BjP)is a state-of-the-art additive manufacturing technique for producing porous magnesium *** MgZn-Zr based BjP samples were assessed for corrosion performance in simulated body fluids by electrochemical and hydrogen evolution *** corrosion rates of the BjP specimens were significantly higher than solid controls,even after accounting for their larger surface areas,suggesting that the BjP microstructure is detrimental to corrosion performance.X-ray computed tomography revealed nonuniform corrosion within the porous structure,with corrosion products forming on the pore *** the pores with hydroxyapatite or polymers greatly improved the corrosion resistance of the BjP samples.

关键词： Magnesium Additive manufacturing Binder jetting Porous Corrosion Biodegradability

Validation of a discrete element model using magnetic resonance measurements

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Particuology 2009年第4期7卷 297-306页

作者： Christoph R.Müller Stuart A.Scott daniel j.Holland Belinda C.Clarke Andrew j.Sederman john S.Dennis Lynn F.Gladden Department of Chemical Engineering and Biotechnology University of CambridgePembroke StreetCambridge CB2 3RAUnited Kingdom

The discrete element model （DEM） is a very promising modelling strategy for two-phase granular systems. However, owing to a lack of experimental measurements, validation of numerical simulations of two-phase granular systems is still an important issue. In this study, a small two-dimensional gas- fluidized bed was simulated using a discrete element model. The dimensions of the simulated bed were 44mm × 10mm × 120 mm and the fluidized particles had a diameter dp = 1.2 mm and density ρp = 1000 kg/m^3. The comparison between DEM simulations and experiments are performed on the basis of time-averaged voidage maps. The drag-law of Beetstra et al. [Beetstra, R., van der Hoef, M.A., ＆ Kuipers,j. A. M. （2007b）. Drag force of intermediate Reynolds number flow past mono- and bidispersed arrays of spheres. AIChE journal, 53,489-501 ] seems to give the best results. The simulations are fairly insensitive to the coefficient of restitution and the coefficient of friction as long as some route of energy dissipation during particle-particle and particle-wall contact is provided. Changing the boundary condition of the gas phase at the side-walls from zero-slip to full-slip does not affect the simulation results. Care is to be taken that the cell sizes are chosen so that a reasonable number of particles can be found in a fluid cell.

关键词： Discrete element modelling Magnetic resonance imaging Voidage Gas-fluidized beds

Comprehensive review of hepatocellular carcinoma with portal vein tumor thrombus:State of art and future perspectives

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Hepatobiliary & Pancreatic Diseases International 2024年第3期23卷 221-227页

作者： Paschalis Gavriilidis Timothy M Pawlik daniel Azoulay Department of Surgery Colchester General HospitalTurner RoadColchester CO45JLUK Department of Surgery The Ohio State Wexner Medical CenterJames Comprehensive Cancer CenterColumbusOHUSA Department of Hepato-Biliary and Liver Transplantation surgery Paul Brousse University HospitalParis-Saclay UniversityVillejuif 94800France

Background:Despite advances in the diagnosis of patients with hepatocellular carcinoma(HCC),70%-80%of patients are diagnosed with advanced stage *** vein tumor thrombus(PVTT)is among the most ominous signs of advanced stage disease and has been associated with poor survival if *** sources:A systematic search of MEDLINE(PubMed),Embase,Cochrane Library and Database for Systematic Reviews(CDSR),Google Scholar,and National Institute for Health and Clinical Excellence(NICE)databases until December 2022 was conducted using free text and MeSH terms:hepatocellular carcinoma,portal vein tumor thrombus,portal vein thrombosis,vascular invasion,liver and/or hepatic resection,liver transplantation,and systematic ***:Centers of surgical excellence have reported promising results related to the individualized surgical management of portal thrombus versus arterial chemoembolization or systemic *** elements to the individualized surgical management of HCC and portal thrombus include precise classification of the portal vein tumor thrombus,accurate identification of the subgroups of patients who may benefit from resection,as well as meticulous surgical *** review addressed five specific areas:(a)formation of PVTT;(b)classifications of PVTT;(c)controversies related to clinical guidelines;(d)surgical treatments versus non-surgical approaches;and(e)characterization of surgical techniques correlated with classifications of ***:Current evidence from Chinese and japanese high-volume centers demonstrated that patients with HCC and associated PVTT can be managed with surgical resection with acceptable results.

关键词： Hepatectomy Liver surgery Liver neoplasms Portal vein tumor thrombus