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Design and Analysis of an Adjustable and Configurable Bio-inspired Heuristic Scheduling Technique for Cloud Based SystemsAl Buhussain, Ali January 2016 (has links)
Cloud computing environments mainly focus on the delivery of resources, platforms, and infrastructure as services to users over the Internet. More specifically, Cloud promises user access to a scalable amount of resources, making use of the elasticity on the provisioning of recourses by scaling them up and down depending on the demand. The cloud technology has gained popularity in recent years as the next big step in the IT industry. The number of users of Cloud services has been increasing steadily, so the need for efficient task scheduling is crucial for improving and maintaining performance. Moreover, those users have different SLAs that imposes different demands on the cloud system. In this particular case, a scheduler is responsible for assigning tasks to virtual machines in an effective and efficient matter to meet with the QoS promised to users. The scheduler needs to adapt to changes in the cloud environment along with defined demand requirements. Hence, an Adjustable and Configurable bio-inspired scheduling heuristic for cloud based systems (ACBH) is suggested. We also present an extensively comparative performance study on bio-inspired scheduling algorithms namely Ant Colony Optimization (ACO) and Honey Bee Optimization (HBO). Furthermore, a networking scheduling algorithm is also evaluated, which comprises Random Biased Sampling (RBS). The study of bio-inspired techniques concluded that all the bio-inspired algorithms follow the same flow that was later used in the development of (ACBH). The experimental results have shown that ACBH has a 90% better execution time that it closest rival which is ACO. ACBH has a better performance in terms of the fairness between execution time differences between tasks. HBO shows better scheduling when the objective consists mainly of costs. However, when there is multiple optimization objectives ACBH performs the best due to its configurability and adaptability.
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Design, Construction, Inverse Kinematics, And Visualization Of Continuum RobotsNeppalli, Srinivas 13 December 2008 (has links)
Continuum robots are the biologically inspired robots that mimic the behaviors of mammalian tongues, elephant trunks, and octopus arms. These robots feature a backboneless structure similar to their biological counterparts, such as termed muscular hydrostats. The drawbacks of two existing designs are examined and a new mechanical design that uses a single latex rubber tube as the central member is proposed, providing a design that is both simple and robust. Next, a novel verification procedure is applied to examine the validity of the proposed model in two different domains of applicability. A two-level electrical control scheme enables rapid prototyping and can be used to control the continuum robot remotely with a joystick via a Local Area Network (LAN). Next, a new geometrical approach to solve inverse kinematics for continuum type robot manipulators is introduced. Given the tip of a three-section robot, end-points of section 1 and section 2 are computed, and a complete inverse kinematics solution for a multisection continuum robot is then achieved by applying inverse kinematics to each section continuum trunk. Moreover, the algorithm provides a solution space rather than a single valid solution. Finally, the techniques involved in visualization of AirOctor/OctArm in 3D space in real-time are discussed.The algorithm has been tested with several system topologies.
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Design of a Biologically-Inspired Climbing Hexapod Robot for Complex ManeuversDiller, Eric David 09 January 2010 (has links)
No description available.
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Bat Inspired Lifesize Ornithopter with Passive Lateral Wing RetractionKelley, Logan Chaney 31 May 2024 (has links)
Bats have a unique flying style that allows them to be highly dexterous in capturing prey and have great freedom of movement in flight. Bats' wings have a wing membrane that is tensioned by their fingers and arms, allowing them to retract their wings laterally in flight. This distinct motion has allowed bats to be the only mammals capable of sustained flight, adding to their evolutionary uniqueness.
This thesis presents the creation of the VALKRIE (Versatile Aerial Lifesize Kinetic Robot Inspired by bat Evolution) project: a to-scale simplified bat-inspired ornithopter that can be remotely controlled, sustain flight, and passively retract and extend its wings laterally. VALKRIE mimics the dimensions and size of its biological counterpart, Hipposideros diadema, a medium-sized bat; setting its aerodynamical constraints to the dimensions of Hipposideros diadema.
Bats' maneuverability is derived from their unique wing motion while in flight, retracting and extending their wings. VALKRIE mimics this motion by simplifying the joint structure of a bat's wing and passively retracting and extending the wings. By simplifying the complex anatomy of bat wing motion, VALKRIE can maintain flight and generate sufficient lift for increasing altitude. With a simplified design, VALKRIE only has two motors that actuate wing flapping, wing retraction, and rotation of the hind legs. With this simplified design, the operator can remotely control VALKRIE by increasing and decreasing the wingbeat frequency and steering to the right and left with the hind legs. / Master of Science / Bats have a unique flying style that allows them to be highly dexterous in capturing prey and have great freedom of movement in flight. Bats' wings have a wing membrane that is tensioned by their fingers and arms, allowing them to retract their wings laterally in flight. This distinct motion has allowed bats to be the only mammals capable of sustained flight, adding to their evolutionary uniqueness.
This thesis presents the creation of the VALKRIE (Versatile Aerial Lifesize Kinetic Robot Inspired by bat Evolution) project: a to-scale simplified bat-inspired ornithopter that can be remotely controlled, sustain flight, and passively retract and extend its wings laterally. VALKRIE mimics the dimensions and size of its biological counterpart, Hipposideros diadema, a medium-sized bat; setting its aerodynamical constraints to the dimensions of Hipposideros diadema.
Bats' maneuverability is derived from their unique wing motion while in flight, retracting and extending their wings. VALKRIE mimics this motion by simplifying the joint structure of a bat's wing and passively retracting and extending the wings. By simplifying the complex anatomy of bat wing motion, VALKRIE can maintain flight and generate sufficient lift for increasing altitude. With a simplified design, VALKRIE only has two motors that actuate wing flapping, wing retraction, and rotation of the hind legs. With this simplified design, the operator can remotely control VALKRIE by increasing and decreasing the wingbeat frequency and steering to the right and left with the hind legs.
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Toward Efficient Bio-Inspired Propulsion: The Effect of Propulsor Shape and Kinematics on System Performance and Efficiency during Bio-inspired LocomotionMatta, Alexander George 25 August 2017 (has links)
Both bird and fish locomotion are thought to be more efficient than the equivalent man-made vehicles driven by propellers/impellers and jet engines. Through studies that decompose the different kinematic and shape effects of these biological systems, we can understand what leads to their high cruising performance and efficiency. Two major studies were conducted. The first was on the effect of different kinematic parameters of large soaring birds on flight performance and the second was on the effect of caudal fin shape on the performance of thunniform swimmers. For the first study on flight performance, flapping, folding, and twist were the wing motions of interest. The second study on swimming performance observed how caudal fin sweep angle affects propulsion while isolating the effect of this shape difference from aspect ratio and area effects. Low order models were primarily used to conduct the bird flight study, though experimental methods were investigated as well. The thunniform swimming study was conducted through experimentation on a biomimetic system.
The flight study found that, under the right circumstances, both wing twist and wing folding have a positive effect on flight performance. However, the impact of wing twist is much larger. To incorporate this wing twist into a robotic system, a new reduced order model that partially accounts for 3D effects was developed and validated. In the future, this model can be used in conjunction with a flight controller to control wing twist.
The swimming study found that caudal fin sweep had a significant impact on performance, moderately swept fins showing the greatest improvement. Using an overly large sweep angle led to diminished performance when compared to the moderately swept fins, but still demonstrated improved performance over a non-swept fin. The increased performance of the moderately swept fins was due to how it affected LEV formation and stability. / Ph. D. / Bird flight and fish swimming are thought to be more efficient than drones and submersible vehicles respectively. By conducting studies on the motion of the wing and the shape of the tail fin, we can gain a better understanding of how to produce efficient vehicles that are inspired by fish/birds. Two major studies were conducted. The first study analyzed the wing motion of birds such as seagulls. The three most important wing motions were analyzed using fast computational simulations. Functional flapping aircraft that can be used in future studies were also constructed. The second study analyzed the tail fin shape of tuna, specifically how the swept shape affects propulsion performance. This study was conducted by operating a robotic tuna with interchangeable tails in a water tunnel.
The computational studies on wing motion showed that controlling twist of the wing in addition to typical flapping motion could greatly improve performance of a flapping bird-like aerial vehicle. To incorporate this wing twist into a future system, a mathematical model that provided aerodynamic predictions was developed. This model can be used in conjunction with a controller to provide efficient real time control of the wing twist.
The experimental swimming study found that fin sweep had a significant impact on performance. Using a moderately swept fin (25-35 degrees) increases thrust production without increased energy expenditure. Fins with greater sweep angles start to yield diminished performance benefits. Using an elliptical area distribution can also lead to increased performance.
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Gait and Morphology Optimization for Articulated Bodies in FluidsAllen, David W. 16 August 2016 (has links)
The contributions of this dissertation can be divided into three primary foci: input waveform optimization, the modeling and optimization of fish-like robots, and experiments on a flapping wing robot. Novel contributions were made in every focus.
The first focus was on input waveform optimization. This goal of this research was to develop a means by which the optimal input waveforms can be selected to vibrationally stabilize a system. Vibrational stabilization is the use of high-frequency, high-amplitude periodic waveforms to stabilize a system about a desired state. The contributions presented herein develop a technique to choose the ``best" input waveform and a discussion of how the ``best" input waveform changes with the definition of ``best."
The next focus was the optimization of a fish-like robot. In order to optimize such robots, a new model for fish-like locomotion is developed. An optimization technique that uses numerous simulations of fish-like locomotion was used to determine the best gaits for traveling at various speeds. Based on these results, trends were found that can determine the optimal gait using a couple relatively simple functions.
The final focus was experimentation on a flapping wing robot in a wind tunnel. These experiments determined the performance of the flapping wing robot at a variety of flight conditions. The results of this research were presented in manner that is accessible to the larger aircraft design community rather than only to those specializing in flapping flight. / Ph. D.
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Information representation on a universal neural ChipGalluppi, Francesco January 2013 (has links)
How can science possibly understand the organ through which the Universe knows itself? The scientific method can be used to study how electro-chemical signals represent information in the brain. However, modelling it by simulating its structures and functions is a computation- and communication-intensive task. Whilst supercomputers offer great computational power, brain-scale models are challenging in terms of communication overheads and power consumption. Dedicated neural hardware can be used to enhance simulation performance, but it is often optimised for specific models. While performance and flexibility are desirable simulation features, there is no perfect modelling platform, and the choice is subordinate to the specific research question being investigated. In this context SpiNNaker constitutes a novel parallel architecture, with communication and memory accesses optimised for spike-based computation, permitting simulation of large spiking neural networks in real time. To exploit SpiNNaker's performance and reconfigurability fully, a neural network model must be translated from its conceptual form into data structures for a parallel system. This thesis presents a flexible approach to distributing and mapping neural models onto SpiNNaker, within the constraints introduced by its specialised architecture. The conceptual map underlying this approach characterizes the interaction between the model and the system: during the build phase the model is placed on SpiNNaker; at runtime, placement information mediates communication with devices and instrumentation for data analysis. Integration within the computational neuroscience community is achieved by interfaces to two domain-specific languages: PyNN and Nengo. The real-time, event-driven nature of the SpiNNaker platform is explored using address-event representation sensors and robots, performing visual processing using a silicon retina, and navigation on a robotic platform based on a cortical, basal ganglia and hippocampal place cells model. The approach has been successfully exploited to run models on all iterations of SpiNNaker chips and development boards to date, and demonstrated live in workshops and conferences.
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Atomic force microscopy probing methods for soft viscoelastic synthetic and biological materials and structuresYoung, Seth Lawton 27 May 2016 (has links)
The focus of this dissertation is on refining atomic force micrscopy (AFM) methods and data analysis routines to measure the viscoelastic mechanical properties of soft polymer and biological materials in relevant fluid environments and in vivo using a range of relevant temperatures, applied forces, and loading rates. These methods are directly applied here to a several interesting synthetic and biological materials. First, we probe poly(n-butyl methacrylate) (PnBMA), above, at and below its glass transition temperature in order to verify our experimental procedure. Next, we use AFM to study the viscoelastic properties of coating materials and additives of silicone-based soft contact lenses in a tear-like saline solution. Finally, a major focus in this dissertation is determining the fundamental mechanical properties that contribute to the excellent sensitivity of the strain sensing organs in a wandering spider (Cupiennius salei) by probing under in vivo conditions. These strain-sensing organs are known to have a significant viscoelastic component. Thus, the cuticle of living spiders is directly investigated in near-natural environments (high humidity, temperatures from 15-40 °C). The main achievements of these studies can be summarized through the following findings: We suggest that full time-temperature-modulus relationships are necessary for the understanding of soft materials systems, and present a practical method for obtaining such relationships. These studies will have a direct impact on both scientists in the metrology field by developing practical experimental procedures and data analysis routines to investigate viscoelastic mechanical properties at the nanoscale, and future materials scientists and engineers by showing via spider mechanosensory systems how viscoelasticity can be applied for functional use in sensing technology.
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3-D Direction of Arrival Estimation with Two AntennasYu, Xiaoju, Xin, Hao 10 1900 (has links)
ITC/USA 2011 Conference Proceedings / The Forty-Seventh Annual International Telemetering Conference and Technical Exhibition / October 24-27, 2011 / Bally's Las Vegas, Las Vegas, Nevada / Inspired by human auditory system, an improved direction of arrival (DOA) technique using only two antennas with a scatterer in between them to achieve additional magnitude cues is proposed. By exploiting the incident-angle-dependent magnitude and phase differences between the two monopole antennas and applying 2-D / 3-D multiple signal classification algorithms (MUSIC), the DOA of an incident microwave signal can be estimated. Genetic algorithm is applied to optimize the scatterer geometry for the 3-D DOA estimation. The simulated results of both the azimuth and three-dimensional DOA estimation have shown an encouraging accuracy and sensitivity by incorporating a lossy scatterer.
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Bio-inspired algorithms for single and multi-objective optimizationTsang, Wai-pong, Wilburn., 曾瑋邦. January 2009 (has links)
published_or_final_version / Industrial and Manufacturing Systems Engineering / Master / Master of Philosophy
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