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At present, with the enormous development of cloud-based applications, the demand of related enterprises for computing and a large number of storage resources is increasing day by day. Due to the characteristics of ultra-large scale and low cost, cloud computing has been gradually applied to complex workflow scheduling problems in various fields. The traditional scheduling algorithms have lot of limitations such as inefficient task management and unreasonable resource allocation. The workflow scheduling problem in the cloud computing environment has been proved to be an NP-complete problem. To solve these problems, this paper proposes an improved ant colony optimization workflow scheduling for workflow execution of tasks within a user-specified deadline. On this basis, a hybrid cloud deadline-constrained cost workflows scheduling algorithm under the hybrid cloud is proposed, which will prioritize scheduling execution in the private cloud, and use the public cloud to schedule part of the workflow when the task execution time exceeds the task deadline constraint. The simulation results show that the proposed workflow scheduling algorithm reduces the cost and attain faster execution time.

The control plane plays an essential role in the implementation of Software Defined Network (SDN) architecture. Basically, the control plane is an isolated process and operates on control layer. The control layer encompasses controllers which provide a global view of the entire SDN. The Controller selection is more crucial for the network administrator to meet the specific use case. This research work mainly focuses on obtaining a better SDN controller. Initially, the SDN controllers are selected using integrated Analytic Hierarchy Process and Technique for Order Preference Similarity to Ideal Solution (AHP and TOPSIS) method. It facilitates to select minimal number of controllers based on their features in the SDN application. Finally, the performance evaluation is carried out using the CBENCH tool considering the best four ranked controllers obtained from the previous step. In addition, it is validated with the real-time internet topology such as Abilene and ERNET considering the delay factor. The result shows that the “Floodlight” controller responds better for latency and throughput. The selection of an optimum controller-Floodlight, using the real-world Internet topologies, outperforms in obtaining the path with a 28.57% decrease in delay in Abilene and 16.94% in ERNET. The proposed work can be applied in high traffic SDN applications.

Two different samples of metakaolin one hardened by acid (10 M phosphoric acid) (MP) and another by alkali (Na2SiO3 of silica modulus 1.1) (MS) are reinforced with reduced graphene oxide (rGO) to form nanocomposites (MPr and MSr) and their macrostructural, microstructural and electrochemical properties are investigated. The presence of polymerised aluminosilicates and alumino-silico phosphates are conclusively proved from XRD. The FTIR spectral analysis of the composites and the synthesized cement were also performed. The results confirmed that the addition of an optimal dose of rGO at 2% does not affect the existing gel network of the final product. However, reinforcement by rGO improved the microstructure as seen from the scanning electron microscopy (SEM) analysis of both MP and MS and also resulted in a strength gain of nearly to 10–12% at all ages of curing (1–28 days). The maximum compressive strength attained at 28 days curing in the MPr sample is 79.15 MPa. The electrochemical properties have been studied through cyclic voltammetry and electrochemical impedance spectroscopy and the results are compared. CV curves are symmetrical but slightly deformed, which indicate a good capacitive behaviour. The specific conductance of MPr and MSr is 53.2 F/g and 42.5 F/g, respectively, which is comparatively higher than that of the geopolymer cement, MP (48.27 F/g) and MS (37.5 F/g). The performance of phosphoaluminate sample is better than the alkali-activated sample due to multiple ionic compositions that form Al–O–P units and Si–O–T (T = Si, Al, P) in the network. The conductive mechanism is predominantly governed by ion drift which can be explained through electrolyte distribution in the matrix via pore/channels in addition to fast conducting H+ ions in the phosphoaluminate. The synergistic effect of rGO–metakaolin geopolymers with a desirable compressive strength balanced by good electrochemical properties gives the newly formed material greater potential for energy storage applications.

Now-a-days, vehicle thefts have very high impact on public safety. There is a need in preventing those thefts. For vehicle theft detection and tracking system, we design a device which is cheap, compatible and also efficient. This device is vehicle tracking hardware which consists of GPS and GSM module for tracking the location of vehicle using co-ordinates and also it has a camera for live face capture of the intruder. In our system, whenever the vehicle’s engine starts, an OTP will be sent to the owner’s mobile for verification, if the OTP is not verified or incorrect OTP is entered, buzzer starts and an alert intimating theft will be sent to the owner. This hardware device is installed on the vehicle in the place where the intruder finds it difficult to identify and remove. The proposed system is an updated version of existing locking system in such a way that the device alerts the owner and notifies with updated location of vehicle at regular intervals and image of the intruder can be seen using live face capture system which secures the vehicles from theft.

The experimental work reported here lay emphasis on mechanical strength, thermal resistance and microstructural characteristics of geopolymer cement to traditional Portland cement prepared under different curing conditions. Portland cement mortars prepared under conventional water curing and air curing aided with 0.5,1, 1.5 and 2.0% dosage (O-1,2,3,4) of poly ethylene glycol (PEG) under different ages. An optimal combination of the PEG has been determined as 1–1.5% with the enhanced the C-S-H gel with better permeability. The strength development of alkali mediated Ground granulated blast furnace slag(GGBS) partially blended with 0, 25, 50, 75% fly ash(FA) (M−1,2,3,4) geopolymer mortars (GPM) prepared under air, water curing and with optimal dose of 1% of PEG . The compressive strength cured under open air and water are compatible that are found to be increased with increase in % GGBS. More than 80% of 28 days(d) strength attained at early ages of 7d in all the GPM samples irrespective of type of curing, suggest that these binders have potential to save time, energy and water that lead to cost economic construction practice. The results on GPM after exposure to elevated temperature 200–600 °C show almost retaining the compressive strength while the control of Ordinary Portland Cement(OPC) mortar significantly loses the strength with the development of wider crack width. The microstructural characterization using Scanning Electron Microscope(SEM) analysis indicate that densification of microstructure depends upon curing regime that effect the thermo mechanical strength significantly.

In this paper, we focus on how nanoadditives such as nano-Al2O3, nano-TiO2 and nano-CaCO3 modify the mechanical and capillary permeability of fly ash cement mortars (5:1). When nanoadditives are added in proportions of 2%, 4% and 6% of the binder volume, hydration products are generated, and thermal conductivity and microstructure of cement mortars undergo a change. Mechanical property measured at 7, 28 and 90 days are measured to understand the underlying pozzolanic reaction and filling effect. The experimental findings reveal that the form and quantity of refractory chemicals in mortar production had an impact hardened matrix at the early age between 7 and 28 days, but thereafter, there is only a marginal strength gain. Nano-Al2O3 and nano-CaCO3 (at 2% of binder volume) additives were able to increase the mortar strength to the extent of 27% of the 28-day compressive strength at 7 days. The addition of 2% nano-TiO2 did not produce this effect. The addition of 6% nano-Al2O3 + nano-CaCO3 in binary and 6% nano-TiO2 + nano-Al2O3 + nano-CaCO3 blend in ternary combinations produced a phenomenally positive effect on the compressive strength with the reduction of capillary permeability at 90 days of setting. The X-ray diffraction patterns of these matrices compared with control showed a clear evidence of reduction of CH growth. Formation of a compact binding gel can be observed in scanning electron microscopic (SEM) pictures. A dense microstructure of binary and ternary nano additive mixes is establish to be favourable in decreasing the thermal conductivity of fly ash blend cement mortar measured at 30 °C. The combination of non-siliceous nano-size materials such as nano-Al2O3, nano-TiO2 and nano-CaCO3 in small quantities have an impact on the pozzolanic reaction with continual strength gain and are effective in counteracting the shortcomings of fly ash blended with cement mortars.

Efficient routing and broadcasting among a set of nodes play a critical role in wireless adhoc networks. for energy efficient routing, a connected dominating set (CDS) based virtual backbone is a promising approach. In the network, one-hop neighbors are selected as multi point relay (MPR) by each node to cover all its two-hop neighbors for the purpose of broadcasting and 2-hop repair. To improve the network lifetime, energy efficient MPR based CDS construction has been proposed by considering the node degree, energy level, node ID and velocity of the node. We also propose a route discovery protocol to relay route request messages, which makes use of the CDS nodes to obtain a stable routing path; 2-hop repair for route maintenance, which reduces the path damage (reduced control packets with lesser consumption of bandwidth) and broadcast storm problem. The simulation results show that the proposed protocol increases the network lifetime up to 30% than other works and effectively repair damaged routes by reducing control packets.

In all the sectors of the economy, issues about sustainable solid waste management and recycling have become increasingly prominent. On the other side, the total energy consumption is dramatically increasing all over world and much of the energy demand lies on building energy consumption for thermal insulation purpose, high-temperature packaging or encapsulating materials. From this point of view, current research explores the possibility of using industrial waste from thermal power plants as a replacement for binder in traditional Portland cement by chemical reaction. Design of composite using 20% partially replacement of fly ash in cement binder (FOPC) and alkali-activated cement (AAFSC) using high-volume fly ash with GGBS as an additive in 4:1 mass ratio, harden at room temperature to study the thermal insulation property. The effect of temperature in the wide range from 30 to 800 °C on thermal conductivity and compressive strengths was evaluated, and the results are compared. The calcium hydroxide groups irrespective of fly ash addition in Portland cement matrix begin to decompose at 300–400 °C and calcium carbonate at 700 °C and melt at 800 °C that were evidenced from thermal stability studies. The thermal impact on strength and mass loss is greatly reduced in AAFSC, provided 50% of virgin strength at 800 °C. The composites comprising FOPC covered by AAFSC and vice versa studied by varying binder-to-filler ratio as 1:1 and 1:2. AAFSC cover integrated well, whereas FOPC drastically failed to retain the structure. Finally, this study confirmed on given thermal-resistant properties and environmental effect, the alkali-activated cement prepared from low energy intensive path be a best option for thermal-resistant building construction.

Cloud computing is a model for enabling ubiquitous, convenient, on-demand network access to the sharable computing resources. The services of cloud could be effectively used for running large-scale data and computation-intensive scientific workflow applications. Workflow scheduling (WFS) plays an important role in the integration of complex applications in multi-cloud computing environment. Normally cloud users want to get rid of vendor lock-in problem and try to use multi-cloud based on their optimal criteria satisfaction. Workflows also constitute different applications. Hence in this chapter we propose an effective service aggregation methodology for different services in the workflow structure. Scheduling the individual applications in the workflow to various cloud services needs to follow a good heuristic and decision model. Here we propose a fuzzy-based multi-objective service selection algorithm, which can be used for WFS. The objectives considered in this work are time, cost, and trust. We device a fuzzy logic-based decision for solving the multi-objective problem. The proposed fuzzy logic-based workflow scheduling (FLWS) provides an optimal schedule for the given workflow, considering the services provided by different cloud providers. The FLWS finds the optimal services for each application in the workflow based on the weights got for the three objectives time, cost, and trust. Hence our FLWS provides a flexible system for optimal decision based on the users’ priority.

Scheduling is a process of mapping resources to tasks and it’s objective is either one or more. This paper focuses on scheduling in heterogeneous multiprocessor systems. Here the resources are processing elements and tasks are the jobs submitted to the processor. The main objectives of multiprocessor scheduling are reducing schedule length, reducing the overall energy consumption, reducing the temperature, reducing failure rates and so on. A Hybrid dual-objective parallel genetic algorithm is applied in the proposed work. Makespan and energy consumption are the two objectives considered. The proposed algorithm determines the global optimal solutions by generating the initial population using some heuristics and then performing parallel genetic operations on it. The main aim of employing parallelism is to find a global optimum solution by avoiding premature convergence in a local optimum and to reduce the running time of the algorithm. Hill climbing is also used in addition, to avoid local optimum solutions. The proposed algorithm balances the tradeoff between energy consumption and makespan according to the inclinations of the users by following weighted sum methodology. Our experimental results demonstrate that the proposed algorithm outperforms the other existing algorithms in terms of both makespan and energy consumption by incurring less running time.

In this work, we report on p-Phenylenediamine (PPD) functionalized reduced graphene oxide (rGO)/Si hybrid-structure designed for UV photodetector applications (PD). The hybrid-structure was characterized by using Fourier Transform-infrared spectroscopy, X-ray photoelectron spectroscopy to confirm the formation of nano-hybrid structure and the experimental results confirmed the covalent bond between rGO and PPD. The diode parameters such as barrier height, series resistance, and ideality factor were estimated for both PPD functionalized rGO (PrGO)/Si and rGO/Si heterostructure by using I-V characteristics. The time-resolved photocurrent spectroscopy used to examine the photoresponse properties of both PrGO/Si and rGO/Si samples with UV light (λ = 382 nm). The experimental results showed that PrGO/Si exhibited significant UV photoresponse than that of rGO/Si PD. The PrGO/Si heterostructure device exhibited photoresponsivity of 1.4 × 10−3 A/W, which is 15 times higher than rGO/Si. The high photoresponse was attributed to the synergistic effects originated from the charge transfer between PPD and rGO. The results proved that PrGO is a promising material for high response photodetector applications.

This paper proposes a new tri-objective scheduling algorithm called Heterogeneous Reliability-Driven Energy-Efficient Duplication-based (HRDEED) algorithm for heterogeneous multiprocessors. The goal of the algorithm is to minimize the makespan (schedule length) and energy consumption, while maximizing the reliability of the generated schedule. Duplication has been employed in order to minimize the makespan. There is a strong interest among researchers to obtain high-performance schedules that consume less energy. To address this issue, the proposed algorithm incorporates energy consumption as an objective. Moreover, in order to deal with processor and link failures, a system reliability model is proposed. The three objectives, i.e., minimizing the makespan and energy, while maximizing the reliability, have been met by employing a method called Technique for Order Preference by Similarity to an Ideal Solution (TOPSIS). TOPSIS is a popular Multi-Criteria Decision-Making (MCDM) technique that has been employed to rank the generated Pareto optimal schedules. Simulation results demonstrate the capability of the proposed algorithm in generating short, energy-efficient and reliable schedules. Based on simulation results, we observe that HRDEED algorithm demonstrates an improvement in both the energy consumption and reliability, with a reduced makespan. Specifically, it has been shown that the energy consumption can be reduced by 5–47%, and reliability can be improved by 1–5% with a 1–3% increase in makespan.

Cloud computing is a new computing paradigm which is gaining wide acceptance among scientific fraternity in the recent years. The services of cloud could be effectively used for running large-scale...

Natural and inorganic materials of Chitosan-Zinc oxide-Neem seed (CS-ZnO-NS) hybrid composite were synthesized by chemical precipitation method. The obtained CS-ZnO-NS hybrid composites were characterized for functional group confirmation by Fourier transform infrared spectroscopy and UV–Visible spectroscopy. The ZnO particles connected to biopolymers exhibited small grains and rod, bullet like structure confirmed by scanning electron microscopy and transmission electron microscopy analysis. The size of the prepared CS-ZnO-NS hybrid composite was found to be 20–80 nm. The crystalline behaviors were determined by X-ray diffraction analysis. The surface area of the prepared hybrid composite was determined using BET analysis. The elemental composition was analyzed by energy dispersive X-ray spectroscopy and thermal behaviors by thermo gravimetric analysis. The obtained result shows that zinc oxide was well able to incorporate into chitosan-neem seed composite which enhances the thermal stability. Further, the antibacterial activity evaluated by agar well diffusion method against Gram-positive Staphylococcus aureus and Gram-negative Escherichia coli bacteria exhibits higher inhibition effect because of ZnO particles presence in the chitosan-neem seed. Hence the CS-ZnO-NS is a promising material for biomedical applications.

Geopolymer a new green binder material describes the family of mineral binders with chemical composition like zeolites but with an amorphous microstructure. Unlike OPC geopolymers do not need calcium silicate hydrate (CSH gel) for binding action. On alkali mediation, soluble alumina and silica from fly ash undergo polycondensation reaction that mostly determined by soluble silica/alumina content, activator type and concentration, water to binder ratio as well admixture. This paper focuses on the effect of silica fume (silica source) on alkali activation of fly ash optimized by response surface methodology. The strength attainment of the optimized mix proportion showed that the addition of 5% silica fume improves the microstructure and hence the compressive strength of the mortar by 25%.

In present study, eco-friendly biosynthesis of Chitosan–Neem seed (CS-NS) composite was prepared by co-precipitation method using aqueous neem seed extract. Cotton fabrics were treated with two different crosslinking agents (Glutaraldehyde and Citric acid) then the synthesized composite coated on cotton fabric by chemical linkage between the composite and the cellulose structure. As synthesized composite materials and treated cotton fabrics were characterized by Fourier transform infrared spectroscopy for functional groups confirmation, X-ray diffraction for crystalline behavior determination, UV–vis spectroscopy analysis for optical property and High resolution scanning electron microscopy for Surface morphological properties. The antibacterial activity of CS-NS composite coated cotton fabric and CS-NS composite coated cotton fabric with crosslinking agents were tested against the gram-positive and gram negative bacteria by agar well diffusion method. The results demonstrated that CS-NS composite with crosslinked coated cotton fabric has higher antibacterial activity than without crosslinked cotton fabric. Thus the chitosan-neem seed composite may be applied to the medical textiles.

A field experiment was conducted during kharif 2015 at Agricultural College Farm, Bapatla on sandy loamsoil to study the phenology, accumulated growing degree days, photo thermal unit, helio-thermal unit, heat useefficiency and performance of fingermillet varieties grown under different sowing dates. The crop was sown on2nd fortnight of July took maximum calendar days, growing degree days, photo thermal unit, helio-thermal unitto attend different phonological stages till maturity. The genotype sown on 2nd fortnight of July (D2) growthand yielded higher. The highest drymatter (3665kg ha-1) at harvest and grain yield (2305 kg ha-1) was recordedwith (D2) 2nd fortnight of July sowing. Among the varieties Chaitanya took highest calendar days growingdegree days, photo thermal unit, helio-thermal unit to reach the maturity. The variety Chaitanya recorded thehighest grain yield at 2nd fortnight of July sowing as compared to all other sowing dates.

In this study biopolymer-inorganic material of chitosan‑copper oxide-neem seed (CS-CuO-NS) biocomposite was successfully synthesized by simple precipitation method and characterized by FT-IR, XRD, HR-SEM, TEM and TGA analyses. From HR-SEM and TEM analysis, CS-CuO-NS biocomposite shows flower and needle like structure respectively. The size of the as prepared CS-CuO-NS biocomposite is found to be 20–100 nm. All the synthesized materials were tested for antibacterial activity against both gram positive like Staphylococcus aureus (S. aureus) and Streptococcus pyogenes (S. pyogenes) and gram negative like Escherichia coli (E. coli) and Klebsiella aerogenes (K. aerogenes) bacterial strains. The maximum zone of inhibition is obtained for CS-CuO-NS biocomposite against S. aureus (23 mm), S. pyogenes (21 mm), E. coli (22 mm) and K. aerogenes (20 mm). The minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) were determined. The antioxidant activity was determined by free radicals scavenging such as 1, 1-Diphenyl-2-picryhydrazyl (DPPH) and 2, 2-azinobis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS). Furthermore, the cytotoxicity effect was investigated against human breast cancer (MCF-7) cell line and the highest cytotoxicity (IC50:16.33 μg/mL) is found to be in biocomposite. From the results of antibacterial, antioxidant and cytotoxic activities, it is concluded that CS-CuO-NS biocomposite may be suitable for biomedical applications.