Filters








49 Hits in 8.4 sec

Defining Reference Area for Prediction of Aerodynamic Coefficients of a Biologically Inspired Hybrid Buoyant Vehicle

Anwar-Ul Haque, Waqar Asrar, Ashraf A. Omar, Erwin Sulaeman
2017 Unmanned Systems  
Geometric and volumetric quantities are usually used to define the reference area for the prediction of aerodynamic coefficients of various aquatic mammals, airships and unmanned vehicle.  ...  However, reference area does not have a unique definition, especially for a hybrid buoyant aerial vehicle having hybrid lifting hull which resembles a Steller sea lion.  ...  Based on the predicted trends of aerodynamic coefficients and a deep literature survey, the projected planform area is proposed as the best option for reference area of a Steller sea lion as well as for  ... 
doi:10.1142/s230138501750011x fatcat:axvssipc6zavfaw6vj4uavraqa

Hydrostatic and Hydrodynamic Characteristics of Swimming Animals- an Inspiration for Hybrid Buoyant Aircraft

Anwar Ul Haque, Waqar Asrar, Ashraf Ali Omar, Erwin Sulaeman, Jaffar Syed Mohamed Ali
2016 Animal Review  
Correlation of the geometric and buoyant properties of the swimming animals with the hybrid buoyant aerial vehicles is an example of this hypothesis.  ...  It was found that the fineness ratio of this animal is of the same order as the optimum value of that for the condition of minimum drag and power required for the buoyant aerial vehicle.  ...  He mentioned that that there is no powerful hydrodynamic basis for the selection of reference area for the estimation of drag coefficient and the same holds good for hybrid aerial vehicles as well.  ... 
doi:10.18488/journal.ar/2016.3.1/101.1.1.9 fatcat:zb4icsnuprbzpcbu44nwsvakbm

Design and Shape Optimization of Unmanned, Semi-Rigid Airship for Rapid Descent Using Hybrid Genetic Algorithm

Vinay Singh, Eric Lanteigne
2019 2019 International Conference on Unmanned Aircraft Systems (ICUAS)  
Mutation: Mutation in a GA refers to the process of alteration of one or more genes in a chromosome to address genetic diversity in a biological population.  ...  Consequently, a hybrid genetic algorithm (HGA), a combination of local search and global search techniques, is employed on the mathematical model of airship hull to optimize its surface area and aerodynamic  ...  Then, the convexity of a function can be formally defined as, for a function f i of n variables to be convex on a convex set S, it must satisfy the inequality condition for any two points x and y in S  ... 
doi:10.1109/icuas.2019.8798185 fatcat:otn5gvvjwvfzzn7hmtgtapzfre

A biologically inspired, flapping-wing, hybrid aerial-aquatic microrobot

Yufeng Chen, Hongqiang Wang, E. Farrell Helbling, Noah T. Jafferis, Raphael Zufferey, Aaron Ong, Kevin Ma, Nicholas Gravish, Pakpong Chirarattananon, Mirko Kovac, Robert J. Wood
2017 Science Robotics  
devices that culminate in a hybrid, aerial-aquatic microrobot.  ...  To develop robots capable of hybrid aerial and aquatic locomotion, we require versatile propulsive strategies that reconcile the different physical constraints of airborne and aquatic environments.  ...  For rotorcrafts, the vehicle needs to tilt by 90° (12) , and this configuration induces large form drag because of the large exposed frontal area.  ... 
doi:10.1126/scirobotics.aao5619 pmid:33157886 fatcat:iu6342sbsrarnlaysi54qtgpem

Shark skin-inspired designs that improve aerodynamic performance

August G. Domel, Mehdi Saadat, James C. Weaver, Hossein Haj-Hariri, Katia Bertoldi, George V. Lauder
2018 Journal of the Royal Society Interface  
Through parametric modelling to query a wide range of different designs, we discovered a set of denticle-inspired surface structures that achieve simultaneous drag reduction and lift generation on an aerofoil  ...  Our findings not only open new avenues for improved aerodynamic design, but also provide new perspective on the role of the complex and potentially multifunctional morphology of shark denticles for increased  ...  Specifically, biological systems have evolved a wide range of drag reducing mechanisms that have inspired the design of synthetic surfaces [18] [19] [20] [21] [22] [23] [24] [25] [26] [27] .  ... 
doi:10.1098/rsif.2017.0828 pmid:29436512 fatcat:vvhpivs4wbcijfpzjbwwht36gi

Continuous Open Access Special Issue "Aircraft Design": Number 2 / 2020 [article]

Dieter Scholz
2020 Zenodo  
As such, the Special Issue "Aircraft Design" can be a home for all those working in the field who regret the absence of an aircraft design journal. SI-2/2020 contains seven papers; an Editorial: 1.)  ...  Design Space Exploration of Jet Engine Components, 4.) Study of Subsonic Wing Flutter, 5.) Design Optimization of a Blended Wing Body Aircraft, 6.) Discrete Mobile Control Surfaces, 7.)  ...  Acknowledgments: The presented work is part of the electro-impulse de-icing system for aircraft, which is funded by State Grid Corporation of China.  ... 
doi:10.5281/zenodo.4624993 fatcat:vkm2umjhcbekzba4x6rbt22pla

Living systems, 'total design' and the evolution of the automobile: the significance and application of holistic design methods in automotive design, manufacture and operation [chapter]

D. Andrews, P. Nieuwenhuis, P.D. Ewing
2006 Design and Information in Biology  
Pugh's 'total design' method is described as a linear activity in that product manufacture and use are considered but not what happens to the product at the end of life.  ...  During the latter decades of the 20th century as products became increasingly complex it became necessary to formalise engineering and product design methods, reputed exponents of which include Gerhard  ...  and vehicles with particular reference to solar powered cars), which demonstrated how a low coefficient of drag (C d ) contributes to energy efficiency.  ... 
doi:10.2495/978-1-85312-853-0/13 fatcat:wuvhjpvqgfhxnboux5frpxkb2q

Operational, regional-scale, chemical weather forecasting models in Europe

J. Kukkonen, T. Balk, D. M. Schultz, A. Baklanov, T. Klein, A. I. Miranda, A. Monteiro, M. Hirtl, V. Tarvainen, M. Boy, V.-H. Peuch, A. Poupkou (+13 others)
2011 Atmospheric Chemistry and Physics Discussions  
Such a single point of reference for European CWF information has not previously been operational.  ...  Sometimes the term biological weather forecasting is used to refer to forecasting of biological constituents in the air, such as various pollen species and airborne allergens. which are the optimal ones  ...  Comparison studies of the various chemical sub-models.  ... 
doi:10.5194/acpd-11-5985-2011 fatcat:ea5r4uylxbcxje6jeak7cnq2hy

Table of Contents

2016 Australian Journal of Primary Health  
The report will recommend acceptable levels of a change in acceleration over a defined time for transit vehicles for several passenger conditions, acceleration conditions, and vehicle types in reference  ...  In task five we develop a numerical model to predict the performance of the hybrid CLT systems under static and dynamic loads. Preliminary results are shown for these two tasks.  ... 
doi:10.1071/pyv22n4toc fatcat:hrwhnxdpjreslhuwi7y4edqmo4

A review of operational, regional-scale, chemical weather forecasting models in Europe

J. Kukkonen, T. Olsson, D. M. Schultz, A. Baklanov, T. Klein, A. I. Miranda, A. Monteiro, M. Hirtl, V. Tarvainen, M. Boy, V.-H. Peuch, A. Poupkou (+13 others)
2012 Atmospheric Chemistry and Physics  
focus areas: emission inventories, the integration of numerical weather prediction and atmospheric chemical transport models, boundary conditions and nesting of models, data assimilation of the various  ...  Finally, this article highlights the most prominent gaps of knowledge for chemical weather forecasting models and suggests potential priorities for future research directions, for the following selected  ...  Kenneth Schere (US Environmental Protection Agency) is thanked for a thorough review of this article, and for his many valuable comments. Edited by: R. Vautard  ... 
doi:10.5194/acp-12-1-2012 fatcat:dfu7klhg3bf2lafhc7xlnp65cu

Space Tourism — From Dream to Reality [chapter]

A. P. Bukley, W. Mendell
2002 Beyond the International Space Station: The Future of Human Spaceflight  
Shuxing Feng created the title of this report, From Dream to Reality. It is a reference to the dream or folk tale in China of travelling to the Moon to visit the mystical princess who lives there.  ...  On the back cover a painting depicts the elegance and romance of love with no bounds. Cover design by Patricia Garner. Front cover image courtesy of NASA, vehicle sketch by Li-Te Cheng.  ...  1 Introduction "Sure it´s expensive…But what´s the cost of an unfulfilled dream?" -Mike Saemisch [Triplett, 1994]  ... 
doi:10.1007/978-94-015-9880-4_31 fatcat:fy3a3afdrfgs3mjfdmuo7gh2ve

Green's-function reaction dynamics: A particle-based approach for simulating biochemical networks in time and space

Jeroen S. van Zon, Pieter Rein ten Wolde
2005 Journal of Chemical Physics  
AM we present two applications of this hybrid meteorological-acoustical calculation scheme: i͒ propagation of impulse noise in a coastal area, and ii͒ propagation of industrial noise in a rural area with  ...  On the prediction of absorption coefficient of porous materials with Finite Elements.  ...  We explore this phenomenon by evaluating the ЉAuditory Image ModelЉ ͑AIM͒, a biologically inspired model of the human auditory system from the outer ear up to central processing.  ... 
doi:10.1063/1.2137716 pmid:16392952 fatcat:tyehqewfnzahfju3rxvivugvaa

Nonnative listeners prefer perceptual cues they know from their L1: Dutch listeners use vowel duration less than English listeners for English final /v/‐/f/

Mirjam Broersma
2008 Journal of the Acoustical Society of America  
AM we present two applications of this hybrid meteorological-acoustical calculation scheme: i͒ propagation of impulse noise in a coastal area, and ii͒ propagation of industrial noise in a rural area with  ...  On the prediction of absorption coefficient of porous materials with Finite Elements.  ...  We explore this phenomenon by evaluating the ЉAuditory Image ModelЉ ͑AIM͒, a biologically inspired model of the human auditory system from the outer ear up to central processing.  ... 
doi:10.1121/1.2933287 fatcat:gqdetkftz5cmrghkql35figuw4

On determination of microphone response and other parameters by a hybrid experimental and numerical method

Salvador Barrera‐Figueroa, Finn Jacobsen, Knud Rasmussen
2008 Journal of the Acoustical Society of America  
A hybrid method for jet noise predictions based on Large Eddy Simulation and Reynolds-Averaged Navier-Stokes simulations.  ...  On the prediction of absorption coefficient of porous materials with Finite Elements.  ...  We explore this phenomenon by evaluating the ЉAuditory Image ModelЉ ͑AIM͒, a biologically inspired model of the human auditory system from the outer ear up to central processing.  ... 
doi:10.1121/1.2933455 fatcat:gl6kkwih6rbkriigc7g6ghdlnq

Relationship between room shape and acoustics of rectangular concert halls

Andrzej K. Klosak, Anders C. Gade
2008 Journal of the Acoustical Society of America  
A hybrid method for jet noise predictions based on Large Eddy Simulation and Reynolds-Averaged Navier-Stokes simulations.  ...  On the prediction of absorption coefficient of porous materials with Finite Elements.  ...  We explore this phenomenon by evaluating the ЉAuditory Image ModelЉ ͑AIM͒, a biologically inspired model of the human auditory system from the outer ear up to central processing.  ... 
doi:10.1121/1.2933354 fatcat:eymbpllxwjcfdbkedeijrtwbwq
« Previous Showing results 1 — 15 out of 49 results