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Computer-based Creativity Enhanced Conceptual Design Model for Non-routine Design of Mechanical Systems

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Chinese Journal of Mechanical Engineering 2014年第6期27卷 1083-1098页

作者： LI Yutong WANG Yuxin DUFFY alex H b Department of Mechanical & Electrical Engineering China University of Petroleum Design Manufacture and Engineering ManagementUniversity of Strathclyde

Computer-based conceptual design for routine design has made great strides, yet non-routine design has not been given due attention, and it is still poorly automated. Considering that the function-behavior-structure（FbS） model is widely used for modeling the conceptual design process, a computer-based creativity enhanced conceptual design model（CECD） for non-routine design of mechanical systems is presented. In the model, the leaf functions in the FbS model are decomposed into and represented with fine-grain basic operation actions（bOA）, and the corresponding bOA set in the function domain is then constructed. Choosing building blocks from the database, and expressing their multiple functions with bOAs, the bOA set in the structure domain is formed. Through rule-based dynamic partition of the bOA set in the function domain, many variants of regenerated functional schemes are generated. For enhancing the capability to introduce new design variables into the conceptual design process, and dig out more innovative physical structure schemes, the indirect function-structure matching strategy based on reconstructing the combined structure schemes is adopted. by adjusting the tightness of the partition rules and the granularity of the divided bOA subsets, and making full use of the main function and secondary functions of each basic structure in the process of reconstructing of the physical structures, new design variables and variants are introduced into the physical structure scheme reconstructing process, and a great number of simpler physical structure schemes to accomplish the overall function organically are figured out. The creativity enhanced conceptual design model presented has a dominant capability in introducing new deign variables in function domain and digging out simpler physical structures to accomplish the overall function, therefore it can be utilized to solve non-routine conceptual design problem.

关键词： conceptual design non-routine design creative enhance model computer-based approach mathematical expression

Volcano video data characterized and classified using computer vision and machine learning algorithms

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Geoscience Frontiers 2020年第5期11卷 1789-1803页

作者： alex J.C.Witsil Jeffrey b.Johnson Department of Geosciences Boise State UniversityBoiseIDUSA

Video cameras are common at volcano observatories,but their utility is often limited during periods of crisis due to the large data volume from continuous acquisition and time requirements for manual *** cameras to serve as effective monitoring tools,video frames must be synthesized into relevant time series signals and further analyzed to classify and characterize observable *** this study,we use computer vision and machine learning algorithms to identify periods of volcanic activity and quantify plume rise velocities from video *** were collected at Villarrica Volcano,Chile from two visible band cameras located^17 km from the vent that recorded at 0.1 and 30 frames per second between February and April *** these two months,Villarrica exhibited a diverse range of eruptive activity,including a paroxysmal eruption on 3 *** to and after the eruption,activity included nighttime incandescence,dark and light emissions,inactivity,and periods of cloud *** quantify the color and spatial extent of plume emissions using a blob detection algorithm,whose outputs are fed into a trained artificial neural network that categorizes the observable activity into five *** shifts from primarily nighttime incandescence to ash emissions following the 3 March paroxysm,which likely relates to the reemergence of the buried lava *** periods exhibiting plume emissions are further analyzed using a row and column projection algorithm that identifies plume onsets and calculates apparent plume horizontal and vertical rise *** onsets are episodic,occurring with an average period of^50 s and suggests a puffing style of degassing,which is commonly observed at ***,the lack of clear acoustic transients in the accompanying infrasound record suggests puffing may be controlled by atmospheric effects rather than a degassing regime at the *** presented here offer a generalized toolset for volcano monito

关键词： Volcano monitoring Plume exit velocity Volcano webcam Image processing Machine learning Villarrica

Conics on barth-bauer octics

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Science China Mathematics 2024年第7期67卷 1507-1524页

作者： alex Degtyarev Department of Mathematics Bilkent UniversityAnkara06800Turkey

We analyze the configurations of conics and lines on a special class of Kummer octic surfaces. In particular, we bound the number of conics by 176 and show that there is a unique surface with 176 conics, all irreducible: it admits a faithful action of one of the Mukai groups. Therefore, we also discuss conics and lines on Mukai surfaces: we discover a double plane(ramified at a smooth sextic curve) that contains 8,910 smooth conics.

关键词： K3-surface octic surface Kummer surface conic Mukai group

Generation scenarios of anodic structures and experimental realization of turbulence in unmagnetized plasma

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Plasma Science and Technology 2020年第8期22卷 90-98页

作者： Prince alex Suraj Kumar SINHA Departimento di Fisica G.Occhialini Universita degli studi di MilanoBicoccaI-20126Italy Department of Physics Pondicherry UniversityKalapetPuducherry 605014India

In the present work,we report development of a DC glow discharge plasma(GDP)set-up to study controlled evolution of anodic structures having distinctive geometry,size and layers,generated in front of a positively biased electrode,submerged in unmagnetized *** such an anodic structure,we have also investigated the condition under which the turbulence is *** of these structures,generated in front of a positively biased electrode,depends on multiple parameters such as the ratio of anode to cathode size,electrode separation,gas pressure,biasing configuration such as anode bias,cathode bias and grounding *** attempted to classify different anodic structures observed experimentally,as anode glow,fireball,anode spot,double layer and multiple double layers(MDLs)based on its physical *** these structures the present investigation is focused on *** number of layers,observed in MDLs varied from as high as six to as low as zero,by controlling the operating discharge parameters,*** were carried out using Langmuir *** analysis of floating potential fluctuations corresponds to a multiple anodic structure showed emergence of turbulence,at its critical stage,satisfying condition for self-organized criticality(SOC).This was identified with three slopes observed in the power spectrum,resembling the sand-pile ***,the GDP is completely different from that of the magnetically confined plasma,the nature of turbulence observed with SOC,is very similar to that observed in the scrape of layer of fusion ***,the present investigation could provide new approach to study turbulence of similar nature,under an experimental condition that is free from the complexities of complicated field geometries used in confinement devices.

关键词： glow discharge plasma anode structure multiple anodic double layer turbulence unmagnetized plasma fireball

A systematic scoping review of study methodology for randomized controlled trials investigating probiotics in athletic and physically active populations

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Journal of Sport and Health Science 2024年第1期13卷 61-71页

作者： alex E.Mohr David b.Pyne Geovana Silva Fogaça Leite Deborah Akins Jamie Pugh College of Health Solutions Arizona State UniversityPhoenixAZ 85004USA Research Institute for Sport and Exercise University of CanberraCanberraACT 2617Australia Laboratory of Functional Fermented Food Faculty of Pharmaceutical SciencesUniversity of São PauloSão Paulo 05508-030Brazil Research Institute for Sport and Exercise Sciences Liverpool John Moores UniversityLiverpool L33AFUK

background:The purported ergogenic and health effects of probiotics have been a topic of great intrigue among researchers,practitioners,and the lay public *** has also been an increased research focus within the realm of sports science and exercise medicine on the athletic gut ***,compared to other ergogenic aids and dietary supplements,probiotics present unique study *** objectives of this systematic scoping review were to identify and characterize study methodologies of randomized controlled trials investigating supplementation with probiotics in athletes and physically active ***:Four databases(MEDLINE,CINAHL,Cochrane CENTRAL,and Cochrane Database of Systematic Reviews)were searched for randomized controlled studies involving healthy athletes or physically active *** intervention with probiotics and inclusion of a control and/or placebo group were *** peer-reviewed articles in English were considered,and there were no date *** were extracted and presented in tabular form to detail study protocols,characteristics,and *** in randomized controlled trials was determined with the Rob 2.0 ***:A total of 45 studies were included in the review,with 35 using a parallel group design and 10 using a cross-over *** half the studies used a single probiotic and the other half a multi-strain *** probiotic dose ranged from 2×10^(8)to 1×10^(11)colony forming units daily,and the length of intervention was between 7 and 150 *** than half the studies directly assessed gastrointestinal symptoms,gut permeability,or the gut *** sex ratio of participants was heavily weighted toward males,and only 3 studies exclusively investigated ***-level adverse events were reported in only 2 studies,although the methodology of reporting varied *** risk of bias was generally low,although details on randomization were lacking in some s

关键词： Exercise Experimental methodology Gastrointestinal symptoms Gut microbiota Probiotic supplementation

On helical behavior of turbulence in the ship wake

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Journal of Hydrodynamics 2013年第1期25卷 83-90页

作者： GOLbRAIKH Ephim EIDELMAN alexander SOLOVIEV alex Physics Department Ben-Gurion University of the Negev Mechanical Engineering Department Ben-Gurion University of the Negev Oceanographic Center NOVA South eastern University

Turbulent ship wake conservation at a long distance is among unsolved problems at present. It is well known that far wakes have a vortical structure and slowly expand with distance. As was obtained by Dubrovin et al., slow expansion of the wake may be related to the distribution of turbulent viscosity in it. In our work we study the effect of helicity in the wake on the behavior of turbulent viscosity. Taking into account the helical nature of the wake, we can clarify the difference between turbulence inside and outside the wake on the one hand and slowing down of its expansion with time on the other hand.

关键词： ship wake turbulent ship wake helical turbulence

Predicting factors for the need of extracorporeal membrane oxygenation for suicide attempts by cardiac medication:a single-center cohort study

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World Journal of Emergency Medicine 2022年第4期13卷 283-289页

作者： David Vandroux Thomas Aujoulat bernard-alex Gaüzère bérénice Puech bertrand Guihard Olivier Martinet Intensive Care Unit Félix Guyon HospitalUniversity Teaching Hospital of La Réunion97400 Saint DenisReunion IslandFrance Cardiosurgical Intensive Care Unit Dupuytren II HospitalUniversity Teaching Hospital of Limoges87042 LimogesFrance UMR 1094 Neuro-épidémiologie Tropicale University of Limoges87042 LimogesFrance Cardiovascular Anesthesia Department Félix Guyon HospitalUniversity Teaching Hospital of La Réunion97400 Saint DenisReunion IslandFrance Service d’Aide Médicale d’Urgence Félix Guyon HospitalUniversity Teaching Hospital of La Réunion97400 Saint DenisReunion IslandFrance

bACKGROUND:Severe poisoning due to the overdosing of cardiac drugs can lead to cardiovascular *** order to decrease the mortality rate,the most severe patients should be transferred as quickly as possible to an extracorporeal membrane oxygenation(ECMO)***,the predictive factors showing the need for venous-arterial ECMO(VA-ECMO)had never been ***:A retrospective,descriptive,and single-center cohort *** consecutive patients admitted in the largest ICU of Reunion Island(Indian Ocean)between January 2013 and September 2018 for beta-blockers(bb),calcium channel blockers(CCb),renin-angiotensin-aldosterone system blockers,digoxin or anti-arrythmic intentional poisonings were *** implementation was the primary ***:A total of 49 consecutive admissions were *** patients had ECMO,39 patients did not have *** patients in ECMO group died,while no patients in the conventional group *** most relevant ECMO-associated factors were pulse pressure and heart rate at first medical contact and pulse pressure,heart rate,arterial lactate concentration,liver enzymes and left ventricular ejection fraction(LVEF)at *** pulse pressure at first medical contact and LVEF were significant after logistic ***:A transfer to an ECMO center should be considered for a pulse pressure<35 mmHg at first medical contact or LVEF<20%on admission to ICU.

关键词： Extracorporeal membrane oxygenation Implementation Cardiac medication Overdose Predicting factor

Rational design of efficient visible-light photocatalysts(1D@2D/0D)ZnO@Ni-doped biObr/bi heterojunction:Considerations on hierarchical structures,doping and SPR effect

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Journal of Materials Science & Technology 2022年第30期125卷 38-50页

作者： Zhouzheng Jin Jingru Li Yiming Zhang Dan Liu Hui Ding bhekie b.Mamba alex T.Kuvarega Jianzhou Gui State Key Laboratory of Separation Membranes and Membrane Processes Tianjin Key Laboratory of Green Chemical Technology and Process Engineeringand School of Material Science and EngineeringTiangong UniversityTianjin 300387China School of Chemical Engineering and Technology Tiangong UniversityTianjin 300387China School of Chemistry Tiangong UniversityTianjin 300387China School of Environmental Science and Engineering Tianjin UniversityTianjin300072China University of South Africa College of ScienceEngineering and TechnologyNanotechnology and Water Sustainability Research UnitFlorida Science Campus 1710South Africa

Simultaneously integrating heterogeneous interface,element doping,and metal decorating was a promising strategy to promote the visible-light-driven photocatalytic ***,we demonstrated a facile solvothermal route for Ni-doped biObr/bi^(0) with ZnO 3D hierarchical heterojunction(denoted as Z@b/biNi).The optimal photocatalysts of Z@b/bi-Ni sample presented a remarkable catalytic performance of high concentrations of tetracycline solution(40 mg/L)than those of the Z@b/bi,Z@b,bOb and ZnO photocatalysts toward the visible-light-driven *** enhanced photocatalytic mechanism can be proposed as follows:(ⅰ)3D hierarchical heterojunction provided more active sites and accelerated the separation of charge carriers for photocatalytic TC;(ⅱ)formation of oxygen vacancies on the surface over Z@b/bi-Ni by in-situ reduction of bi^(0) and Ni doping could serve as the active sites for oxygen activation to adsorb free O_(2) and generate more superoxide radicals;(ⅲ)SPR effect of bi metal were beneficial to carrier separation and also act as the active site to trap O_(2) *** work clarified the role of unique morphologies,surface plasmonic resonance(SPR)effect of metal bi,and Ni doping in Z@b/bi-Ni,and its photocatalytic reaction mechanism was proposed by a series of experiments,characterization and DFT calculations,arousing a new perspective to design hierarchical heterojunction photocatalysts.

关键词： Hierarchical heterojunction Oxygen vacancies Doping Ni SPR effect Photocatalysis

Modeling novel methodologies for unmanned aerial systems–Applications to the UAS-S4 Ehecatl and the UAS-S45 bálaam

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Chinese Journal of Aeronautics 2019年第1期32卷 58-77页

作者： Maxime alex Junior KUITCHE Ruxandra Mihaela bOTEZ ETS Laboratory of Active ControlsAvionics and AeroServoElasticity LARCASE

The rising demand for Unmanned Aerial Systems(UASs) to perform tasks in hostile environments has emphasized the need for their simulation models for the preliminary evaluations of their missions. The efficiency of the UAS model is directly related to its capacity to estimate its flight dynamics with minimum computational resources. The literature describes several techniques to estimate accurate aircraft flight dynamics. Most of them are based on system identification. This paper presents an alternative methodology to obtain complete model of the S4 and S45 unmanned aerial systems. The UAS-S4 and the UAS-S45 models were divided into four sub-models, each corresponding to a specific discipline: aerodynamics, propulsion, mass and inertia, and actuator. The‘‘aerodynamic" sub-model was built using the Fderivatives in-house code, which is an improvement of the classical DATCOM procedure. The ‘‘propulsion" sub-model was obtained by coupling a two-stroke engine model based on the ideal Otto cycle and a blade Element Theory(bET) analysis of the propeller. The ‘‘mass and the inertia" sub-model was designed utilizing the Raymer and DATCOM methodologies. A sub-model of an actuator using servomotor characteristics was employed to complete the model. The total model was then checked by validation of each submodel with numerical and experimental data. The results indicate that the obtained model was accurate and could be used to design a flight simulator.

关键词： Aerodynamics Aerospace propulsion Flight dynamics Unmanned aerial vehicles modeling