Nonlinear Aerodynamic Damping of Sharp-Edged Beams at Low Keulegan-Carpenter Numbers

Slender sharp-edged flexible beams such as flapping wings of micro air vehicles (MAVs), piezoelectric fans and insect wings typically oscillate at moderate-to-high values of non-dimensional frequency parameter β with amplitudes as large as their widths resulting in Keulegan–Carpenter (KC) numbers of order one. Their oscillations give rise to aerodynamic damping forces which vary nonlinearly with the oscillation amplitude and frequency; in contrast, at infinitesimal KC numbers the fluid damping coefficient is independent of the oscillation amplitude. In this article, we present experimental results to demonstrate the phenomenon of nonlinear aerodynamic damping in slender sharp-edged beams oscillating in surrounding fluid with amplitudes comparable to their widths. Furthermore, we develop a general theory to predict the amplitude and frequency dependence of aerodynamic damping of these beams by coupling the structural motions to an inviscid incompressible fluid. The fluid–structure interaction model developed here accounts for separation of flow and vortex shedding at sharp edges of the beam, and studies vortex-shedding-induced aerodynamic damping in slender sharp-edged beams for different values of the KC number and the frequency parameter β. The predictions of the theoretical model agree well with the experimental results obtained after performing experiments with piezoelectric fans under vacuum and ambient conditions

Formulation and Evaluation of Ciprofloxacin Solid Dispersion Controlled Release Floating Capsules for Solubility Improvement

Solid dispersions in water soluble carriers have attracted considerable interests as a mean of improving the dissolution rate and hence possibly bioavailability range of hydrophobic drugs. The poor solubility of ciprofloxacin leads to poor dissolution and hence variation in bioavailability. The purpose of present investigation was formulation and evaluation of controlled release floating capsule of ciprofloxacin with improved solubility and dissolution rate. In present study solid dispersion using various carriers like mannitol and lactose in different ratios were prepared by solvent evaporation method. The prepared solid dispersions were characterized for drug content, solubility and dissolution rate. The dissolution rate substantially improved for ciprofloxacin from its solid dispersions compared with pure drug. Dissolution rate increased with increase in carrier content. The dissolution rate was increased 3 folds with solid dispersions containing 1:4 of drug: lactose. The granules of ciprofloxacin solid dispersion containing 1:4 of drug: lactose ratio was prepared by wet granulation method using polymer such as ethyl cellulose and HPMC. The prepared granules were evaluated to preformulation studies such as angle of repose (18.41-24.22), bulk density, tapped density, compressibility index (11.31-12.75) and hausner’s ratio. All the parameters shows that the granules having good flow properties. These granules had converted into the capsule forms. Then the formulated capsules were taken to the evaluation studies such as weight variation, release study, buoyancy and floating duration (more than 6 hrs.). We can conclude that all the parameters were within the acceptable limits

A Modified Image Template for FELICS Algorithm for Lossless Image Compression

Abstract In this paper, a lossless image compressio

Taste masking of oral pregabalin liquid preparation by using ion exchange resins

The purpose of this study was to use cation exchange resins to mask Pregabalin's unpleasant taste. Dowex-50, a crosslinked polystyrene backbone, was employed. DRCs were synthesised in batches with drug-to-resin ratios of 1:1, 1:2, and 1:3. The optimal drug-to-resin ratio as well as the time required for maximum complexation were discovered. In this work, an attempt was made to develop a taste-masked Pregabalin solution using a simple, rapid, and cost-effective flavour masking approach, such as complexation among ion exchange resin, that could be acceptable to industries. To mask the flavour, researchers used a combination of ion-exchange resins such as doshion P 542, Tulsion 344, Indion 234, Indion 204, and Kyron T 114, as well as formulation into a solution. The generated suspensions were tested for taste, drug content, particle size, viscosity, sedimentation volume, drug release, and accelerated stability. Kyron T 114 has been shown to effectively disguise the drug among the various resins. The newly developed formulation also has the benefit of simplifying the manufacturing process and being cost-effective. According to drug release studies, the entire medicament was released within 20 minutes.&nbsp

PREPARATION AND EVALUATION OF A TASTE-MASKED ARTEMETHER ORAL SUSPENSION

Objective The antimalarial drug Artemether is bitter in taste. The purpose of this work is to construct a taste-masked Artemether resinate employing ion exchange resins.   Methodology The process for drug resin complexation was adjusted in terms of drug resin ratio and medium pH. FTIR and DSC measurements were used to characterise the taste masked complex. As an ion exchange resin, Indion 204 was used. It was combined with medication in various ratios: Indion was generated at various times and pH values and the extent of complexation was determined.   Results The result indicates that a 1:1 ratio of Indion 204 to resin resulted in the largest amount of complexation after four hours of mixing. These resinate then converted into granules and they exhibit angle of repose, bulk density, and flow characteristic values that are acceptable. The loading of drugs was greater than 99 percent. Based on drug content, suitable amount of drug-resinate was taken for formulation. Then Suspension was studied for general appearance, viscosity, sedimentation ratio, drug release, resuspendability. The release test showed that 92.46% drug release within 120 min.   Conclusion Hence we can conclude that, the Indion 204 has been proved to be useful as taste masking agent. Thus we are able to achieve our objectives of preparing taste masked suspension of Artemether with minimum excipients and simple method of manufacturing.&nbsp

On the Design, Implementation, Analysis, and Prototyping of a 1-mu s, Energy-Efficient, Carrier-Class Optical-Ethernet Switch Router

The integration of layer-2 carrier-class packet technologies with optical transport network is termed as packet-optical integration and is being deployed by service providers for migration from legacy SONET/SDH systems. We present a state-of-the-art carrier-class switch router that facilitates packet-optical integration, thereby achieving best of both the optical and packet worlds. The premise of this switch router is the use of carrier ethernet technology as a packet enabler for achieving statistical multiplexing at fine granularities, while maintaining rich operations, administration, maintenance, and provisioning features. To this end, we proposed the omnipresent ethernet concept that uses binary routing and source routing to support: 1) layer 2 and layer 3 switching and routing, 2) low latency of the order of 1-5 mu s even for layer 3 processing, and 3) low-energy consumption. The omnipresent ethernet framework leads to a software defined networking solution, whereby a centralized controller admits services and configures nodes based on homogenous networking parameters. In this paper, we report a commercial implementation of a packet-optical network demonstrated by our designed, fabricated, developed carrier ethernet switch router (CESR). We discuss the architectural considerations, design, and implementation of both the hardware and the control software. A switch architecture achieving 1-mu s port-to-port delay across layers 1, 2, and 2.5 based on an opportunistic principle of virtual output queuing is showcased. The novelty is a scalable 96-Gbps cross connect fabric implemented in a field programmable gate array using a two-stage buffer system. A multistate software defined control plane is also reported. An exact analysis of the switch architecture using a combinatorial G/G/1 model is developed. An energy audit of the CESR is showcased. A test bed in the lab replicating a field deployment is presented. An exhaustive set of test cases are developed to test our designed CESR. Results are shown for latency, throughput, service support, frame-size stability, power, and bit error rate, thus validating our design

Development and modification of the natural polymers by converting them into nanobiocomposite

The main target ofTthis study is to develop an  antibacterial  chitosan  nanocomposite  fabric  among  in  situ   crated   silver  nanoparticles  utilizing   Vitex  leafTextract,  which  i s amedicinal herb. The CNCFs were evaluated using scanning  electron  microscopy  (SEM), Fourier transform infrared (FT-IR) spectroscopy,Xray diffraction (XRD), and antimicrobial testing. Additionally, these CNCFs have excellent antibacterial characteristics. These CNCFs could be used  in medical  applic  ations like surgical aprons, wound cleansing, wound  dressing,  and  hospital  bed  mat erials, as they were manufactured utilising a simple and environmentally acceptable approach