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Rolling in Nature and Robotics: A Review

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Journal of Bionic Engineering 2006年第4期3卷 195-208页

作者： Rhodri H.Armour Julian f.v.vincent Centre for Biomimetic and Natural Technologies Department of Mechanical Engineering University of Bath Bath BA2 7AY UK

This paper presents a review of recent rolling robots including Rollo from Helsinki University of Technology, Spherical Mobile Robot from the Politecnico of Bad, Sphericle from the University of Pisa, Spberobot from Michigan State University, August from Azad University of Qazvin and the University of Tehran, Deformable Robot from Ritsumeijan University, Kickbot from the Massachusetts Institute of Technology, Gravitational Wheeled Robot from Kinki University, Gyrover from Carnegie Mellon University, Roball from the Université de Sherbrooke, and Rotundus from the Angstroem Space Technology Center. Seven rolling robot design principles are presented and discussed （Sprung central member, Car driven, Mobile masses, Hemispherical wheels, Gyroscopic stabilisation, Ballast mass - fixed axis, and Ballast mass - moving axis）. Robots based on each of the design principles are shown and the performances of the robots are tabulated. An attempt is made to grade the design principles based on their suitability for movement over an unknown and varied but relatively smooth terrain. The result of this comparison suggests that a rolling robot based on a mobile masses principle would be best suited to this specific application. Some wonderful rolling organisms are introduced and defined as ＂active＂ or ＂passive＂ depending on whether they generate their own rolling motion or external forces cause their rolling.

关键词： Rolling robot tumbleweed wheel ballast Gryoscope

PDC钻头钻进岩石破碎过程及其与钻进规程参数关系的分析研究

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钻探工程 2024年第1期51卷 5-14页

作者：汤凤林赵荣欣 НескоромныхB.B. 李博周欣段隆臣 Чихоткин В.Ф. 上海市建筑科学研究院有限公司上海200032 中国地质大学(武汉)工程学院湖北武汉430074 西伯利亚联邦大学(СибирскийФедеративныйУниверситет) 俄罗斯克拉斯诺雅尔斯克市(г.КрасноярскРоссия)660095 湖北省地震局湖北武汉430064

PDC复合片钻头在地质勘探和石油天然气钻井等领域得到了广泛的应用,取得了很好的技术经济效果。但是,对于其碎岩过程及其与钻进规程参数间的关系研究不够深入,影响了技术经济指标的进一步提高。俄罗斯钻探工作者在这方面做了很多工作,... 详细信息

PDC复合片钻头在地质勘探和石油天然气钻井等领域得到了广泛的应用,取得了很好的技术经济效果。但是,对于其碎岩过程及其与钻进规程参数间的关系研究不够深入,影响了技术经济指标的进一步提高。俄罗斯钻探工作者在这方面做了很多工作,取得了一定效果,值得引起我们的注意。例如,他们建议,由于岩石破碎方式是变化的,所以,尽量使岩石破碎处于体积破碎状态;如果把钻头每转进尺能耗量指标作为一个评价指标考虑进去,则评价系统会更加科学和更加全面;钻头每转进尺,不是越高越好,有一个最优值,这个最优值与钻进规程参数密切相关;提出了临界钻进规程的概念,即当轴载和转速的乘积高达一定数值时,切削具温度急剧上升、钻头磨损明显加剧,冲洗液量再大也无济于事,因此,此时应该采取措施,及时调整规程参数,避免钻进过程处于临界规程状态,以便使钻进处于正常状态,继续钻进下去。

关键词： PDC钻头油气钻井地质勘探技术经济指标岩石破碎过程钻进规程参数

Time-Series Embeddings from Language Models:A Tool for Wind Direction Nowcasting

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Journal of Meteorological Research 2024年第3期38卷 558-569页

作者： Decio ALvES fabio MENDONCA Sheikh Shanawaz MOSTAfA fernando MORGADO-DIAS University of Madeira Campus Universitário da Penteada9020-105FunchalPortugal Interactive Technologies Institute/Laboratory for Robotics and Engineering Systems and Agência Regional para o Desenvolvimento da Investigação Tecnologia e InovaçãoEdif.Madeira TecnopoloCaminho da Penteada piso-29020-105FunchalPortugal

Wind direction nowcasting is crucial in various sectors,particularly for ensuring aviation operations and *** this context,the TELMo(Time-series Embeddings from Language Models)model,a sophisticated deep learning architecture,has been introduced in this work for enhanced wind-direction *** by using three years of data from multiple stations in the complex terrain of an international airport,TELMo incorporates the horizontal u(east-west)and v(north-south)wind components to significantly reduce forecasting *** a day with high wind direction variability,TELMo achieved mean absolute error values of 5.66 for 2-min,10.59 for 10-min,and 14.79 for 20-min forecasts,processed within a swift 9-ms/step *** degree-based analysis,in comparison,yielded lower performance,emphasizing the effectiveness of the u and v *** contrast,a vanilla neural network,representing a shallow-learning approach,underperformed in all analyses,highlighting the superiority of deep learning methodologies in wind direction *** is an efficient model,capable of accurately forecasting wind direction for air traffic operations,with an error less than 20°in 97.49%of the predictions,aligning with recommended international *** model design enables its applicability across various geographical locations,making it a versatile tool in global aviation meteorology.

关键词： wind nowcasting wind components wind direction time series prediction deep learning

Recovery rates of persistent post-COvID-19 olfactory dysfunction using psychophysical assessment:A longitudinal cohort study

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World Journal of Otorhinolaryngology-Head and Neck Surgery 2024年第2期10卷 79-87页

作者： Jeremy P.Tervo Patricia T.Jacobson Brandon J.vilarello Tiana M.Saak francesco f.Caruana Liam W.Gallagher Joseph B.Gary David A.Gudis Paule v.Joseph D.P.Devanand Terry E.Goldberg Jonathan B.Overdevest Columbia University vagelos College of Physicians and Surgeons New YorkNew YorkUSA Department of Otolaryngology-Head and Neck Surgery New York-Presbyterian/Columbia University Irving Medical CenterNew YorkNew YorkUSA Department of Otolaryngology-Head and Neck Surgery University of PittsburghPittsburghPennsylvaniaUSA Department of Otolaryngology-Head and Neck Surgery University of MinnesotaMinneapolisMinnesotaUSA National Institute of Alcohol Abuse and Alcoholism Section of Sensory Science and Metabolism&National Institute of Nursing ResearchBethesdaMarylandUSA New York-Presbyterian/Columbia University Irving Medical Center New YorkNew YorkUSA

Objectives:Persistent olfactory dysfunction(OD)following loss of smell associated with SARS-Cov-2 infection is a major feature of long *** on the prevalence of persistent OD predominantly rely on self-reported olfactory *** studies have tracked longitudinal rates of recovery using psychophysical assessment among patients presenting for evaluation of persistent OD beyond a window of acute *** anchored in standardized testing methods are needed to counsel patients who fail to acutely regain their sense of *** study aims to quantify the degree of persistent OD in post-COvID-19 patients who experience subjective and psychophysical ***:We grouped participants presenting for OD evaluation into cohorts based on both subjective and psychophysical olfactory status at a baseline assessment and assessed their olfactory abilities with a visual analogue scale and the Sniffin'Sticks extended test at baseline and 1-year time *** had confirmed a history of COvID-19 by lab evaluation or clinical diagnosis if lab evaluation was not ***:Baseline olfactory evaluation was completed by 122 participants,53 of whom completed the 1-year follow-up *** participants presenting with perceived OD,74.5%had confirmed psychophysical OD at baseline,with 55.1%at 1-year *** had reliable trends in self-rated versus psychophysically tested olfactory function at both time *** total threshold,discrimination,and identification(TDI)score improved by+3.25 points in the cohort with psychophysical OD(p=0.0005),with this improvement largely attributable to an increase in median threshold scores(+2.75 points;p=0.0004).Conclusions:OD persists in a significant number of patients who fail to acutely recovery their sense of smell after COvID-19,with many demonstrating lingering deficits at *** in threshold,but not discrimination or identification,most significantly mediate improvement

关键词： long COvID olfaction post-COvID condition smell dysfunction

Understanding the precursor chemistry for one-step deposition of mixed cation perovskite solar cells by methylamine route

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Journal of Energy Chemistry 2021年第6期30卷 386-391,I0010页

作者： Manuel vásquez-Montoya Juan f.Montoya Daniel Ramirez franklin Jaramillo Centro de Investigación Innovación y Desarrollo de Materiales CIDEMATUniversidad de Antioquia UdeACalle 70 No.52-21MedellínColombia

Upscaling perovskite solar cell fabrication is one of the key challenges in the pathway for *** slow evaporation of frequently used solvents(DMf or DMSO) limits the fast perovskite layer crystallization,hindering their implementation in large scale deposition ***,methylamine-based precursors have demonstrated rapid crystallization,leading to uniform and specular ***,their application has been limited to MAPbI3 perovskites with limited efficiency and *** this work,we report the requirements for stabilizing α-phase of mixed cation perovskites with high amount of formamidinium by using a methylamine-based *** found that even though,there are many methods for incorporating the methylamine(MA) in precursors or films;the MA content determines stabilization of the α-phase and therefore the viscous-solution route is the only method to incorporate high amounts of *** low amounts of MA,perovskite tend to crystallize in 1D dimensional fA_(3)(MA)PbI5 phases due to the incomplete solvation of the *** contrast,high MA ratio induces a full solvation of the clusters,leading to a rapid crystallization and a full stabilization of the active 3D α-*** results open a window in the development and understanding of new precursors for the fabrication of high efficient,stable and scalable perovskite devices.

关键词： Methylamine Stabilizingα-phase Mixed cation perovskite precursor formamidinium Upscaling Perovskite Solar cells

New filler metal systems for the brazing of titanium alloys

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China Welding 2015年第3期24卷 1-5页

作者： v. f. Khorunov S. v. Maksymova v. v. voronov E.O. Paton Electric Welding Institute NASU 11 Bozhenko Str. Kiev 03680 Ukraine

It＇ s well known welding takes the leading role in development of titanium structures. However, in number of cases technological processes of brazing are more appropriate and, sometimes, being the single possible, in particular, during production of multilayer thin-wall structures. It should be noted that brazing filler metals of Ti-Cu-Ni, Ti-Zr-Cu-Ni, Zr-Ti-Ni and Cu-Zr-Ti systems in a form of plastic foils, as well as in powder form are mainly used in world practice for brazing of titanium alloys. Present work provides the results of complex investigations of brazing filler metals of Ti-Zr-fe, Ti-Zr-Mn and Ti-Zr-Co systems using differential thermal analysis, light and scanning microscopy, X-ray microspectrum analysis. Data on melting ranges of pilot alloys were obtained, and liquidas su^Caces of given systems using simplex-lattice method were build. Brazing filler metals covering brazing temperature range of current structural titanium materials based on solid solutions as well as intermetallics were proposed. Structure, chemical inhomogeniety and strength characteristics of brazed joints were studied. It is determined that brazing of solid solution based alloys （OT4, vT6 ） using indicated brazing fiUer metals ensures strength characteristics of joints, which are not inferior to that obtained with application of known brazing filler metals even if they are received at lower brazing temperature.

关键词： vacuum brazing titanium alloys inter-metallic alloys brazing filler metals brazed joints structure,strength of brazed joints

Technosols Made of Wastes to Improve Physico-Chemical Characteristics of a Copper Mine Soil

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Pedosphere 2013年第1期23卷 1-9页

作者： v.ASENSIO f.A.vEGA M.L.ANDRADE E.f.COvELO Department de Bioloxía vexetal e Ciencia do Solo Facultade de Bioloxia Universidade de VigoLagoas Marcosende 36310 Vigo Pontevedra (Spain)

Mine tailing soils created from the copper extraction in Touro Mine （Northwest Spain） are very degraded both physically and chemically. Three plots in this mine tailing were amended with Technosols in different proportions in each one to know if this mixture improved the physico-chemical characteristics of the mine soil and contaminated it with heavy metals. The Technosols were made of organic wastes, including mussel residues, wood fragments, sewage sludges and paper mill ashes. An unamended area was used as a control soil. Pseudototal and diethylenetriaminepentaacetic acid （DTPA）-extractable contents of A1, Cr, Cu, fe, Mn, Ni, Pb and Zn were determined in soil samples. The untreated soil had significant limitations for vegetation growth. All the Technosols improved the properties of the mine soil by increasing organic carbon and pH value, but they added Ni, Pb or Zn to the soil. It is advisable to check whether the heavy metal concentrations of the wastes are hazardous or not before adding to soils. It is also necessary to study the effect of these wastes over time and in more areas to conclude if they are actually favourable to restore degraded mine soils.

关键词： heavy metals mine tailing vegetation growth waste amendment

miniSCIDOM: a scintillator-based tomograph for volumetric dose reconstruction of single laser-driven proton bunches

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High Power Laser Science and Engineering 2024年第2期12卷 41-50页

作者： A.Corvino M.Reimold E.Beyreuther f.-E.Brack f.Kroll J.Pawelke J.D.Schilz M.Schneider U.Schramm M.E.P.Umlandt K.Zeil T.Ziegler J.Metzkes-Ng Helmholtz-Zentrum Dresden–Rossendorf DresdenGermany Technische Universität Dresden DresdenGermany OncoRay–National Center for Radiation Research in Oncology Faculty of Medicine and University Hospital Carl Gustav CarusTUD Dresden University of TechnologyHelmholtz-Zentrum Dresden–RossendorfDresdenGermany Current affiliation:Institut Curie UniversitéPSLCNRS UMR3347OrsayFrance Current affiliation:Universitätsklinikum freiburg FreiburgGermany

Laser plasma accelerators(LPAs)enable the generation of intense and short proton bunches on a micrometre scale,thus offering new experimental capabilities to research fields such as ultra-high dose rate radiobiology or material *** spectrally broadband,laser-accelerated proton bunches allow for tailored volumetric dose deposition in a sample via single bunches to excite or probe specific sample *** rising number of such experiments indicates a need for diagnostics providing spatially resolved characterization of dose distributions with volumes of approximately 1 cm^(3) for single proton bunches to allow for fast online *** we present the scintillator-based miniSCIDOM detector for online single-bunch tomographic reconstruction of dose distributions in volumes of up to approximately 1 cm^(3).The detector achieves a spatial resolution below 500μm and a sensitivity of 100 *** detector performance is tested at a proton therapy cyclotron and an LPA proton *** experiments’primary focus is the characterization of the scintillator’s ionization quenching behaviour.

关键词： beam monitoring detectors laser-driven proton beams scintillator-based diagnostics ultra-high dose rate

Applications—Influence of Biology on Engineering

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Journal of Bionic Engineering 2006年第3期3卷 161-177页

作者： Julian f. v. vincent Department of Mechanical Engineering The University of Bath Bath BA2 7AY UK

Examples are presented showing the way in which biological systems produce a range of functions which can be implemented in engineering, such as feedback-control of stiffness （muscles and nervous system）, the design of fault-free structures （trees） and damage-tolerant materials （wood） and high performance insulation （penguin feathers） and shock absorbers （hedgehog spines）.

关键词： Applications Influence of Biology on Engineering