62 research outputs found
The Effects of Nano Fillers on Space Charge Distribution in Cross-Linked Polyethylene
The performance of polymeric insulation will be distorted by the accumulation of space charge. This will lead to local electric field enhancement within the insulation material that can cause degradation and electrical breakdown. The introduction of nanofillers in the insulation material is expected to reduce the space charge effect. However, there is a need to analyze potential nanofillers to determine the best option. Therefore, the objective of this research work is to examine two types of nanofillers for Cross-Linked Polyethylene (XLPE); Zinc Oxide (ZnO) and Acrylic (PA40). The effects of these nanofillers were measured using the Pulsed-Electro Acoustic (PEA) method. The development of space charge is observed at three different DC voltage levels in room temperature. The results show that hetero charge distribution is dominant in pure XLPE materials. The use of both nanofiller types have significant effect in decreasing the space charge accumulation. With nanofillers, the charge profile changed to homo-charge distribution, suppressing the space charge formation. Comparisonbetween both the nanofillers show that PA40 has better suppression performance than ZnO
A time efficient and accurate retrieval of range aggregate queries using fuzzy clustering means (FCM) approach
Massive growth in the big data makes difficult to analyse and retrieve the useful information from the set of available data’s. Statistical analysis: Existing approaches cannot guarantee an efficient retrieval of data from the database. In the existing work stratified sampling is used to partition the tables in terms of static variables. However k means clustering algorithm cannot guarantees an efficient retrieval where the choosing centroid in the large volume of data would be difficult. And less knowledge about the static variable might leads to the less efficient partitioning of tables. Findings: This problem is overcome in the proposed methodology by introducing the FCM clustering instead of k means clustering which can cluster the large volume of data which are similar in nature. Stratification problem is overcome by introducing the post stratification approach which will leads to efficient selection of static variable. Improvements: This methodology leads to an efficient retrieval process in terms of user query within less time and more accuracy
Novel Proposed Work for Empirical Word Searching in Cloud Environment
People's lives have become much more convenient as a result of the development of cloud storage. The third-party server has received a lot of data from many people and businesses for storage. Therefore, it is necessary to ensure that the user's data is protected from prying eyes. In the cloud environment, searchable encryption technology is used to protect user information when retrieving data. The versatility of the scheme is, however, constrained by the fact that the majority of them only offer single-keyword searches and do not permit file changes.A novel empirical multi-keyword search in the cloud environment technique is offered as a solution to these issues. Additionally, it prevents the involvement of a third party in the transaction between data holder and user and guarantees integrity. Our system achieves authenticity at the data storage stage by numbering the files, verifying that the user receives a complete ciphertext. Our technique outperforms previous analogous schemes in terms of security and performance and is resistant to inside keyword guessing attacks.The server cannot detect if the same set of keywords is being looked for by several queries because our system generates randomized search queries. Both the number of keywords in a search query and the number of keywords in an encrypted document can be hidden. Our searchable encryption method is effective and protected from the adaptive chosen keywords threat at the same time
DESIGN, FORMULATION AND CHARACTERIZATION OF TENOFOVIR MICROEMULSION AS ORAL DRUG DELIVERY
ABSTRACT The aim of the present research was to design, formulate and evaluate Tenofovir Microemulsion. Tenofovir, a Nucleotide Reverse transcriptase inhibitor belongs to the category of anti retro viral drug. The oral bioavailability of Tenofovir is 25% due to its poor water solubility. An attempt was made to enhance solubility by formulating oral Microemulsion of Tenofovir. The solubility of Tenofovir in various Oils, Surfactants and Cosurfactants were checked to optimize the components of Microemulsion. Pseudo ternary diagrams were constructed to identify the area of Microemulsion region. A Microemulsion system with oleic acid as Oil phase, Tween 20 as surfactant and Ethanol as Cosurfactant was developed for oral delivery of Tenofovir. To achieve the objective of present study, Microemulsion formulations were prepared by using different ratios of Oil, Surfactant: Cosurfactant and Water. The prepared formulations of Tenofovir were characterized for thermo dynamic stability studies, pH, transparency, viscosity, drug content and in vitro drug release. Particle size and Zeta potential of optimized formulation were found to be 54.30nm and -5.61mV. Among four formulations, TME4 shows highest drug release of 86.88%. The invitro release was found to follow Non-fickian diffusion mechanism. These results demonstrate the potential use of Microemulsion for improving the Bioavailability of poor water soluble compound Tenofovir. Key words: Phase diagrams, Centrifugation, Kinetic models, Stability. INTRODUCTION Successful oral delivery of drugs has always remained challenge to the drug delivery field, since approximately 40% of the new drug candidates have poor water solubility associated with low bioavailability. Lipidbased formulations have attracted great deal of attention to improve the oral bioavailability of poorly water soluble drugs. In fact, the most novel approach is to incorporate lipophilic or hydrophilic drugs into inert lipid vehicles such as oils, surfactants through formulating in the form of microemulsions, self-emulsifying formulations. These lead to increased solubilization further increase in therapeutic efficacy. A microemulsion is a system of water, oil and an amphiphile which is a single optically isotropic and thermodynamically stable liquid solution. Microemulsions (μE) are usually in the range of 10-100 nm. These homogeneous systems, which can be prepared over a wide range of surfactant concentration and oil to water ratio, are all fluids of low viscosit
Fabrication of precast concrete slab panels incorporating foundry sand and blast furnace slag as a potential wall insulator
Increasing construction cost and environmental sustainability are persistent issues of concern in the built environment. Consequently, new generation materials are required for practical applications in order to considerably tackle the challenges. This work focused on the fabrication and testing of precast concrete slab panels produced using industrial by-products - foundry sand, as a partial replacement of fine aggregate, and ground granulated blast furnace slag as cement admixture. Foundry sand was substituted for manufactured sand in levels 0%, 10%, 20%, 30%, 40% and 50%, while granulated blast furnace slag (GGBS) was constantly added to cement at 30%, in a standard designed M40 concrete grade. The result showed that 40% of foundry sand was adequate for appreciable strength development in the modified mix. The same mixture was also found to have better insulation characteristics than the conventional mix. The wall panels tested in this study are quite economical when compared to competing building technologies
Alkali activated binders: Challenges and opportunities
Alkali activated binders (AAB) are gaining huge research attention in recent years, due to their potential
to totally be used in a zero-cement composite. Ordinary Portland cement (OPC) is characterized by high
energy usage and carbon emission from its production process, which thus shows the need for AAB development.
AAB are a sustainable replacement for OPC, as they can be produced from waste materials generated
by various industrial processes. This paper explored the properties of different types of waste used
as a solitary and binary combination for AAB, alongside their effects on the resulting composites. A general
summary of the opportunities of AABs are also discussed. It was concluded that, with more research
and developments dedicated to the field of AAB, AAB can be practical replacement of OPC for large-scale
applications in the near future
Optimization of Drilling Rig Hydraulics in Drilling Operations Using Soft Computing Techniques
The primary goal for all oil and gas producing companies is to produce oil as much as possible by
optimization with lower cost. One way to increase the productivity index is essentially related to a
proper drilling technique. In this study, optimization of drilling rig hydraulics in drilling operations was
performed using soft computing techniques. Data such as flow rate, the angle of inclination, yield point,
plastic viscosity and depth of the well were used as input. Thus, using the neural network (ANN)
approach, five process parameters are the inputs to the model and output from this model is cutting
concentration. The best model for the drilling rig contains five input parameters, seven hidden layers
and one output parameter. The optimization aids the inherent characteristics of the system as well as
the factors like exorbitant surface torque, unexplained drop in the rate of infiltration and a sudden
change in surface weigh
Shear Resistance of portal Frame Reinforced with Bamboo and Steel Rebar: Experimental and Numerical Evaluation
The main objective of this study is to evaluate the shear resistance of portal frame fabricated with bamboo and steel rebar by following experimental and numerical approaches. In support of sustainable construction, bamboo stripes were utilized as a partial replacement of steel rebar at tension zone of members that are subjected to lateral loading. The performance of nominal portal frame, which are fabricated with steel reinforcement was compared to the portal frames having several replacements of steel reinforcement with bamboo, in terms of seismic resistance and lateral load capacity. The experimental data was correlated based on software analysis using ABAQUS. The partial replacement of steel with bamboo under tension zone of the beams in portal frame was found to be highly effective, and also that the flexural rigidity of the partial bamboo reinforced frame was slightly higher than the nominal portal frame. This study provides insight on the possibility of reinforcing structural members with bamboo, when lateral loading is imminent on the structure
Synthesis, physico-mechanical properties, material processing, and math models of novel superior materials doped flake of carbon and colloid flake of carbon
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