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The parameter estimation optimisation with constraints for the nonlinear complex system requires a serious of computation. This paper introduced a novel constrained optimisation method named Lagrangian-based state transition algorithm (LSTA) to solve problems in distributed cloud computing environment. LSTA with the physical constraints involved in solving the problems which occurs while the conventional techniques are used. In LSTA, the updating of the result to an optimisation problem with constraints known as, a state transition. The Lagrangian multiplier is used as a constraint for state transition process to estimate the drying process system effectively. The experiments are conducted in the cloud computing environment and simulated results validated the proposed LSTA methodology for parameter estimation. This method is a promising way for system identification due to its searching competency, enduring performance considering physical limitations and quick convergence.

Sugarcane and energycane (Saccharum spp. hybrids) are prominent sources of sugar, ethanol, as well as high-value bioproducts globally. Genetic analysis for trait improvement of sugarcane is greatly hindered by its complex genome, limited germplasm resources, long breeding cycle, as well as recalcitrance to genetic transformation. Here, we present a biolistic-based transformation and bioreactor-based micro-propagation system that has been utilized successfully to transform twelve elite cane genotypes, yielding transformation efficiencies of up to 39%. The system relies on the generation of embryogenic callus from sugarcane and energycane apical shoot tissue, followed by DNA bombardment of embryogenic leaf roll discs (approximately one week) or calli (approximately 4 weeks). We present optimal criteria and practices for selection and regeneration of independent transgenic lines, molecular characterization, as well as a bioreactor-based micro-propagation technique, which can aid in rapid multiplication and analysis of transgenic lines. The cane transformation and micro-propagation system described here, although built on our previous protocols, has significantly accelerated the process of producing and multiplying transgenic material, and it is applicable to other varieties. The system is highly reproducible and has been successfully used to engineer multiple commercial sugarcane and energycane varieties. It will benefit worldwide researchers interested in genomics and genetics of sugarcane photosynthesis, cell wall, and bioenergy related traits.

The advancement of flow measurement techniques continues to extend experimental boundaries and thus significantly contributes to improving our understanding of both basic and applied aerodynamics. This is particularly apparent in the case of particle image velocimetry (PIV), where its application has furthered the existing knowledge in several areas of helicopter rotor aerodynamics. The complex nature of helicopter rotor flows presents unique challenges to experimentalists, including transonic flow, concentrated vortices and dynamic stall. To illustrate the impact of the technological advancements on the way helicopter aerodynamics is studied today, the development of PIV since the early nineties of the last century is reviewed and some recent PIV applications are described. Using examples of main rotor wakes, dynamic stall and flow control investigations, the capabilities of large–scale, time–resolved and volumetric PIV are summarized.

Numerical and experimental analysis of a synthetic jet actuator in quiescent air is reported. The study focuses on the actuator itself and on the vorticity field as well as on structures that are generated by the actuator. Large eddies simulation was used for numerical analysis and phase-locked, two-dimensional microscopic-particle image velocimetry technique was used in the experiment. In the numerical simulation, the equations were integrated using a nondissipative scheme that enforces discrete conservation of kinetic energy. The internal cavity flow of the actuator was part of the simulation. The actuator under consideration is of a unique design, fabricated to accommodate practical issues associated with helicopter rotor application. However, it has the same operating principles as a conventional synthetic jet actuator. Harmonics of the forcing frequency were traced in the velocity field. Insight into the evolution of the vortical structures, jet flapping, and onset of turbulence in the jet was retrie...

Aim: To evaluate and compare the variations in the inclination of occlusal plane of casts mounted on Artex articulator using a facebow with a fixed value and customized nasion indicator. Materials and Methods: Twenty two subjects were selected for this investigation. Two maxillary impressions were made, and casts poured. For each of the twenty two subjects, the facebow records were made with, Artex face-bow using a fixed value nasion indicator and customized nasion indicator and mounted. The angle between the occlusal plane of upper cast and the upper articulator arm was measured with a Universal bevel protractor and compared with the gold standard cephalometric value. Results: It shows that, when angle was measured between maxillary occlusal plane and upper member of the articulator, on the mounted cast using a customized nasion indicator and fixed value nasion indicator against the gold standard cephalometric value as a whole, it was found to be not significant. But, if each patient were evaluated individually, there found to be the difference in the angle. Discussion and Conclusion: Variation in occlusal plane was very minimal and close to the cephalometric value when using customized nasion indicator compared to fixed value nasion indicator on the Artex.

Vortex aperiodicity introduces random uncertainty in the measured vortex center location. Unless corrected, this may lead to systematic uncertainty in the vortex properties derived from the measured velocity field. For example, the vortex core size derived from averaged or mean flow field appears larger because of aperiodicity. Several methodologies for aperiodicity correction have been developed over the past two decades to alleviate this systematic uncertainty. However, these do not always reduce the accompanying random uncertainty. The current work shows that the analysis methods used to derive the vortex properties from the measured velocity field play an important role in the resultant random uncertainty in these properties; perhaps, even more important role than the aperiodicity correction methodology itself. It is hypothesized that a class of methods called global methods, which use a large extent of measured data, yield a smaller measurement uncertainty compared to local methods. This hypothesis is verified using a newly proposed global method based on a planar least-squares fit. The general applicability of the method is demonstrated using previous particle image velocimetry measurements of rotor tip vortices. The results clearly demonstrate a reduced random uncertainty in the vortex core properties, even in the presence of secondary vortical structures. Furthermore, the results are independent of the choice of aperiodicity correction methodology.

Performance and flowfield measurements were conducted on a small-scale cyclorotor for application to a micro air vehicle. Detailed parametric studies were conducted to determine the effects of the number of blades, rotational speed, and blade pitching amplitude. The results showed that power loading and rotor efficiency increased when using more blades; this observation was found over a wide range of blade pitching amplitudes. The results also showed that operating the cyclorotor at higher pitching amplitudes resulted in improved performance, independently of the number of blades. A momentum balance performed using the flowfield measurements helped to quantify the vertical and sideward forces produced by the cyclorotor; these results correlated well with the force measurements made using load balance. Increasing the number of blades increased the inclination of the resultant thrust vector with respect to the vertical because of the increasing contribution of the sideward force. The profile drag coefficient of the blade sections computed using a momentum deficit approach correlated well with typical values at these low chord Reynolds numbers. Particle image velocimetry measurements made inside the cage of the cyclorotor showed that there are rotational flows that, when combined with the influence of the upper wake on the lower half of the rotor, explain the relatively low efficiency of the cyclorotor.

The aerodynamic interaction between an unsteady, inclined synthetic jet and a crossflow boundary layer was studied as a precursor toward applying active flow control concepts for rotor applications, such as dynamic stall control and fuselage drag reduction. Because the flowfield offered numerous challenges from a measurement perspective, several experiments were carried out using a phase-locked, two-dimensional microscopic particle image velocity technique in a building block approach, by adding one complexity after another. The procedure began with boundary layer measurements made on a simple flat plate using the microscopic particle image velocity technique. Velocity measurements were made deep in the viscous sublayer, as close as 20μm from the surface. Following this, the synthetic jet actuator was characterized while operating in quiescent air as well as in crossflow. The results showed that the evolution of the synthetic jet in crossflow was substantially different from its evolution in quiescent air, suggesting that any flow physics or performance prediction (for example, the depth of penetration of the jet into the boundary layer) made based on the quiescent flow conditions may not be applicable in crossflow. All the momentum added to the boundary layer had its source from the synthetic jet actuator, and the penetration of the jet was limited to the viscous sublayer and log layer; the outer layer was unaffected, despite using a jet to freestream velocity ratio of four. Significant effort was also made to validate the microscopic particle image velocity technique and evaluate its capability to accurately resolve such a complex flowfield. To this end, microscopic particle image velocity measurements were compared with hot-wire measurements made on a simple steady jet, as well as an unsteady, periodic synthetic jet. Excellent correlation was found between the two techniques, validating microscopic particle image velocity measurements.

The formation and evolutionary characteristics of the blade tip vortices generated by a hovering rotor were studied using dual-plane stereoscopic particle image velocimetry. The dual-plane stereoscopic particle image velocimetry technique permitted noninvasive measurement of the three components of the velocity field and the nine components of the velocity gradient tensor, a capability not possible with classical particle image velocimetry. The dual-plane stereoscopic particle image velocimetry method is based on coincident flow measurements made over two differentially spaced laser sheet planes. A polarization-based approach was used in which the two laser sheets were given orthogonal polarizations, with filters and beam-splitting optical cubes placed so that the cameras imaged Mie scattered light from only one or other of the laser sheets. The digital processing of the images used a deformation grid correlation algorithm that was optimized for the high velocity gradient and small-scale turbulent flows found inside the blade tip vortices. High-resolution flow imaging of the vortex sheet in the wake behind the rotor blade, combined with detailed turbulence measurements, revealed the presence of several turbulent flow features during the vortex roll-up process that appear to play an important role in its final evolution. The dual-plane stereoscopic particle image velocimetry measurements also included the fluctuating terms involved in the Reynolds-averaged stress transport equations. The results confirm that an isotropic assumption of turbulence is invalid inside blade tip vortices and that stress should not be represented as a linear function of strain. The dual-plane stereoscopic particle image velocimetry measurements were also compared with velocity and turbulence measurements made using a laser Doppler velocimeter system, with good correlation.

An experiment was conducted to identify and measure the sources of uncertainty that are associated with the application of particle image velocimetry to the measurement of the vortical wakes trailing from helicopter rotor blades. Phase-resolved, three-component particle image velocimetry measurements were performed in the wake of a subscale rotor operating in hover, and were compared with high-resolution three-component laser Doppler velocimetry measurements obtained with the same rotor under identical operating conditions. This helped formulate the essential experimental conditions that need to be satisfied for particle image velocimetry to accurately resolve the high-velocity gradient, high streamline curvature flows that are present inside the rotor wake and in the blade tip vortices. Uncertainties associated with the calibration, acquisition, and processing of the particle image velocimetry images were analyzed in detail. It was shown that the optimization of laser pulse separation time is fundamental to reduce the errors associated with acceleration and curvature effects. Similarly, the interrogation window size was shown to play a critical role in determining the velocity gradient bias errors. The correlation between the laser Doppler velocimetry and particle image velocimetry measurements of the tip vortex characteristics, such as core radius and peak swirl velocity, were found to be excellent.

This paper focuses on one of the most prominent flow features of the hovering rotor wake, the close interaction of the tip vortex with a following blade. Such vortex interactions are fundamental determinants of rotor performance, loads, and noise. Yet, they are not completely understood, largely due to the lack of sufficiently comprehensive experimental data. The present study aims to perform such comprehensive measurements, not on hovering helicopter rotors (which hugely magnifies test complexity) but using fixed-wing models in controlled wind tunnel tests. The experiments were designed to measure, in considerable detail, the aerodynamic loading resulting from a vortex interacting with a semi-span wing, as well as the wake resulting from that interaction. The goal of the present study is to answer fundamental questions such as (a) the influence of a vortex passing below a wing on the lift, drag, tip vortex, and the wake of that wing and (b) the strength of the forming tip vortex and its relation to the wing loading and/or the tip loading. This paper presents detailed wing surface pressure measurements that result from the interaction of the wing with an interacting vortex trailing from an upstream wing. The data show large lift distribution changes for a range of wing–vortex interactions including the effects of close encounter with the vortex core. Significant asymmetry in the vortex-induced lift loading was observed, with the increase in wing sectional lift outboard of the interacting vortex (closer to the tip) being much smaller than the corresponding decrease inboard of the vortex.

The unsteady aerodynamics of a biomimetic inspired flapping-wing mechanism has been analyzed by performing detailed phase-locked diagnostics of its flow field. Flow visualization and particle image velocimetry results have shown the presence of a shed dynamic stall vortex that spans across most of the wing span. The shedding of this type of leading-edge vortex was accompanied by the formation of another leading-edge vortex before the first vortex reached the midchord, resulting in multiple shedding leading-edge vortices on the top surface of the wing during each wing stroke. A strong starting vortex was also formed at the trailing edge of the wing during the early part of its translational stroke. This vortex continuously gained strength from shed vorticity as the wing accelerated into its stroke. The starting vortex remained close to the trailing edge until the wing reached midstroke. A pair of vortices that continuously trailed from the root and tip of the wing were identified, both of which induced a significant downwash velocity over the wing surface. These trailed vortices were found to exhibit a contracting wake structure as they convected into the wake below the wing, consistent with an increase in slipstream velocity. The evolution of the tip and root vortex pair showed rapid diffusive characteristics with an increase in time (wake age).

Afl ow-visualization experiment was conducted on an insect-based flapping-wing mechanism. This enabled greater understanding and insight to be gained on the unsteady aerodynamic phenomena that are responsible for the enhanced lift of wings operating at low Reynolds numbers in hovering flapping flight. Flow-visualization images were acquired with a strobbed laser sheet to illuminate the flow, which was seeded with a mineral oil fog. The general flowfield structure was found to consist of a folded wake, with a relatively large starting vortex at the end of each half-stroke. A large flow recirculation region was generated in the plane of flapping, which was centered around the two extreme flapping displacements. These general flowfield features were enhanced by detailed observations of the local flowfield around the wing section. One observation was the presence of multiple vortices on the top surface of the wing as it underwent translation. Furthermore, the local flowfield images clearly showed the growth of the leading-edge vortex as a function of span and identified the presence of separated flow on the outboard regions of the wing. These experimental results were supported by a free vortex modeling of the wake developments. The model was found to predict similar wake flowfield dynamics to that found in the experiments. This research has contributed to a better understanding of the unsteady aerodynamic mechanisms that are responsible for the enhanced lift of insect-based flapping wings in hover.

An experiment was performed to help quantify the interdependence of viscous/turbulent diffusion and straining effects on the development of helicopter rotor tip vortices. The properties of the blade tip vortices were measured in the wake of a small-scale hovering rotor and compared to the results for the case when the wake approached a solid boundary. The presence of the boundary created velocity gradients that forced the tip vortex filaments to strain, allowing the effects of this process on the vortices to be measured relative to the baseline case without the boundary. It is shown that vortex stretching begins to decrease the viscous core size, and when the strain rates become large, this can balance the normal growth in the vortex core resulting from diffusion. The present results were used to help develop a more general tip vortex model suitable for use in a variety of helicopter rotor aeroacoustic applications. The proposed engineering model combines the effects of turbulent diffusion and strain on the vortex core growth. The empirical coefficients of this model have been derived based on the best available results from rotating-wing tip vortex measurements.

Automation has been growing in recent years for the manufacturing industries to increase productivity. Multiple robotic arms are used to handle materials for lifting in flexible directions. The vertical rotation of a 360 degree single arm is considered in this research on a position servo drive with brushless DC motor. The load torque of an arm varies depending upon the angular displacement due to gravity, so it requires four-quadrant operation of the drive with a robust feedback controller. This paper deals with the design and performance comparison of a conventional PID feedback controller with a fuzzy-based PID controller and suggests the most suitable controller. The design was implemented in real time through the dSPACE DS1104 controller environment to verify the dynamic behaviors of the arm.

Numerical and experimental analysis of synthetic jet actuator is reported. The study focuses on the actuator itself and on the vorticity field and structures that are generated by the actuator. Phase-locked, 2-D microscopic-PIV technique (MPIV) was used in experiment, and large eddies simulation (LES) was used for numerical analysis. The two methods were first validated for a circular steady jet, continuing with synthetic jet, emanated from a practical device design to quiescent air. The development of vortical structures and their interactions was carefully studied. The insight obtained is an important building block for better understanding of the interaction of synthetic jets and boundary layers. Nomenclature

Experiments were performed to better understand the aerodynamic flow field of a flapping-wing micro air vehicle. High-resolution laser sheet flow visualization and particle image velocimetry (PIV) analyses have shown the presence of folded vortex filaments that are trailed from the tip and root of the wing, which are combined with a shed dynamic stall vortex with a strong spanwise flow toward the wing tip. This leading-edge vortex gains strength as the translational motion of the wing accelerates through midstroke. There is a subsequent shedding of this vortex, but with the simultaneous formation of another leading-edge vortex. The generation of the second vortex occurs before the first vortex reaches mid-chord, enhancing overall lift. This second vortex moves along the chord during supination, before finally being shed from the trailing-edge of the wing. A starting vortex forms near the trailing-edge as the wing starts to accelerate during the downstroke/upstroke of the flapping cycle. This starting vortex grows larger in size, gaining energy from further shed vortices, until the wing reaches the mid-point of the cycle. The folded root and tip vortices that trail from the flapping wing have been found to be relatively strong, and move inward and axially downward as the wing moves through its flapping cycle. The close proximity of the starting vortex, as well as the trailed root and tip vortices, has a large influence on the downwash over the wing. This suggests that any modeling techniques used to predict the lift on flapping wings must fundamentally take into account the three-dimensional, unsteady effects associated with its complex vortex wake structure.

Results were obtained for several high frequency tests conducted on biomimetic, flapping-pitching wings. The wing mass was found to have a significant influence on the maximum frequency of the mechanism because of a high inertial power requirement. All the wings tested showed a decrease in thrust at high frequencies. In contrast, for a wing held at 90◦ pitch angle, flapping in a horizontal stroke plane with passive pitching caused by aerodynamic and inertial forces, the thrust was found to be larger. To study the effect of passive pitching, the biomimetic flapping mechanism was modified with a passive torsion spring on the flapping shaft. Results of some tests conducted with different wings and different torsion spring stiffnesses are shown. A soft torsion spring led to a greater range of pitch variation and produced more thrust at slightly lower power than with the stiff torsion spring. Some flow visualization images have also been obtained using the passive pitching wings.

Advent of osseointegration has rapidly led to use of dental implants over recent years. Implant complications are often inadvertent sequelae of improper diagnosis, treatment planning, surgical method, and placement. This can be overcome by using surgical guides for implant positioning. Although conventionally made surgical guide are used, the clinical outcome is often unpredictable, and even if the implants are well placed, the location and deviation of the implants may not meet the optimal prosthodontic requirements. High accuracy in planning and execution of surgical procedures is important in securing a high success rate without causing iatrogenic damage. This can be achieved by computed tomography, 3D implant planning software, image-guided template production techniques, and computer-aided surgery. This article evaluates about the various systems of conventionally made surgical guide using radiograph and also the newer computer generated surgical guide in detail.