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This paper evaluates the electrical performance of photovoltaic (PV) modules with and without anti-soiling coating at different incidence angles and layers of soiling. Two test coupons were evaluat...

Globally abundant wave energy for power generation attracts ever increasing attention. Because of non-linear dynamics and potential uncertainties in ocean energy conversion systems, generation productivity needs to be increased by applying robust control algorithms. This paper focuses on control strategies for a small ocean energy conversion system based on a direct driven permanent magnet synchronous generator (PMSG). It evaluates the performance of two kinds of control strategies, i.e., traditional field-oriented control (FOC) and robust adaptive control. The proposed adaptive control successfully achieves maximum velocity and stable power production, with reduced speed tracking error and system response time. The adaptive control also guarantees global system stability and its superiority over FOC by using a non-linear back-stepping control technique offering a better optimization solution. The robustness of the ocean energy conversion system is further enhanced by investigating the Lyapunov method and the use of a DC-DC boost converter. To overcome system complexity, turbine-generator based power take-off (PTO) is considered. A Matlab/Simulink study verifies the advantages of a non-linear control strategy for an Oscillating Water Column (OWC) based power generation system.

Yttrium and cerium co-doped ZnO nanoparticles were synthesized by combustion route and characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), Brunauer-Emmett-Teller (BET), energy dispersive spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS), UV-visible diffuse reflectance spectroscopy (UV-vis DRS), photoluminescence (PL) and electrochemical impedance spectroscopy (EIS) techniques. The introduction of yttrium ions has efficiently increased the relative percentage of Ce3+ ions in ZnO. Yttrium and cerium co-doped ZnO shows efficient photo activity for hydrogen evolution (10.61 mmol/((g·h)) higher than previously reported optimal value for rare earth co-doped ZnO photocatalysts. This remarkably increased hydrogen evolution can be ascribed to the synergy between electronic anchoring effect of Y3+/Y2+ and Ce4+/Ce3+ redox couples. This report presents new idea for the synthesis of efficient photocatalyst using economical route and ion anchoring effect. The hydrogen evolution was also tested using Na2S and Na2SO3 as electron donors under visible light illumination. The synthesized photocatalysts also exhibit high stability.

[Submitted in IEEE J-BHI]Retinopathy refers to any damage in the retina that causes visual impairments or even blindness. Identification of retinal lesions plays a vital role in accurately grading retinopathy and for its effective treatment. Optical coherence tomography (OCT) imaging is the most popular non-invasive technique used for the retinal examination due to its ability to screen abnormalities in early stages. Many researchers have presented studies on OCT based retinal image analysis over the past. However, to our best knowledge, there is no framework yet available which can extract retinal lesions from multi-vendor OCT scans and utilize them for the intuitive grading of the human retina. To cater this lack, we propose a deep retinal analysis and grading framework (RAG-FW). RAG-FW is a hybrid convolutional framework which extracts retinal lesions such as intra-retinal fluid, sub-retinal fluid, hard exudates, drusen and chorioretinal abnormalities (including fibrotic scars and choroidal neovascular membranes) from multi-vendor OCT scans. Furthermore, it utilizes them for the lesion-influenced grading of retinopathy as per the clinical standards. RAG-FW has been trained using 113,261 retinal OCT scans from which 112,261 scans were used for training and 1,000 scans were used for the validation purposes. Furthermore, it has been rigorously tested on 43,613 scans from five highly complex publicly available datasets where it achieved the mean intersection-over-union score of 0.8055 for extracting the retinal lesions and the F1 score of 99.52% for correctly classifying the retinopathy cases. The source code of RAG-FW is available at http://biomisa.org/index.php/downloads/.

The recent increase in electricity prices and the usage of single-phase induction motors (SPIMs) provide a stimulus for a focused research on energy-efficient optimization of SPIM load such as air-conditioners and refrigerators. Variable speed control of SPIM provides a promising way forward to reduce its power consumption. However, during variable speed operation under the popular constant $V/f$ method, SPIM is required to operate at non-rated conditions. The operation of SPIM at non-rated conditions disturbs its symmetrical and balanced operation, thus degrading its efficiency. Moreover, soft-starting of SPIM at non-rated conditions is also challenging due to the resulting reduction in starting-torque. In this article, after a detailed analysis of SPIM energy-efficiency, an improved sensor-less optimal speed control strategy is developed to enable the symmetrical and balanced operation of SPIM at all the operating points over the entire speed-range to improve its performance. A novel algorithm, termed as the phase-shift algorithm, is also devised for efficient implementation of the proposed optimal speed control strategy. In addition, a unique framework for efficient soft-starting of SPIM at very low frequencies is also developed. The simulation-based results of the motor operated through the proposed phase-shift algorithm validate the energy-saving potential of the proposed control strategy.

Poisonous plants are widely distributed and may have risk of phytotoxicity upon mixing with medicinal plants. Several species of Cestrum genus are poisonous and linked with many serious health issues. In the present study, cross-mixing of a toxic plant, Cestrum diurnum with morphologically resembling medicinal plant, Adhatoda vasica was studied using chemical fingerprinting approach. LC-ESI-MS/MS tool was used to develop the chemical fingerprints of three toxic species of Cestrum, including, C. diurnum, C. nocturnum and C. parqui. Total forty-three compounds were identified using high-resolution LC-ESI-MS/MS data comparison. Chemometric analyses were done to compare the distribution of identified compounds present in these Cestrum species. One of the identified compounds, nornicotine (a toxic compound) was also quantified using LC-IT-MS/MS. Adulteration study was conducted by mixing toxic C. diurnum in A. vasica with various ratios (w/w) and five differentiable compounds were identified to detect the adulteration. The method was able to detect up to the limit of 5% mixing of toxic C. diurnum. Moreover, cytotoxicity of the methanolic extracts of these three species were also studied on normal human PBMC (peripheral blood mononuclear cells) and all found to be toxic, while the C. nocturnum showed the highest level of toxicity with the IC50 12.5 μg/mL.

Sustainable smart city development experience various challenges, such as legislation and policies, funding, infrastructure, and technological aspects. Numerous studies have highlighted the importance of sustainability concepts in smart cities' development. However, there is scarce research focusing on the challenges faced for the development of sustainable smart cities. This study aimed to develop a conceptual framework that provides critical challenges faced by private and government organisations, and the respective solutions of the challenges for the development of sustainable smart cities. Pakistan has been chosen as a case study that yields a total of 17 respondents from the executive, managerial, and operational levels of private enterprises and government organisations involved in smart city development. This research is a preliminary step towards providing insights and significance of infusing sustainability in the development of smart cities. The proposed conceptual framework can act as a practise guideline for practitioners to prepare themselves for sustainable smart city development.

Remotely operated underwater vehicle (ROUV) provides an interesting and extensible platform to search the wanted objects and for the inspection of deep sea. The basic goal of this research is to control the position and stabilize the dynamic behavior of ROUV. In this study, we design the dual controller approach design for controlling the overall responses of ROUV. The design dual controller consists of model reference adaptive control (MRAC) along with proportional integral derivative (PID) controller and an integral use for the feedback of the design scheme. The dynamic moments and disturbances in the system is dealt by MRAC controller and PID controller is responsible for tuning the adaptive gains of the system. However, Lyapunov stability criterion is responsible for the stability of the system. The inclusion of integrator as a feedback in the system increases the order of the system model, but it helps to eliminate the steady state error and also improves the convergence rate of the system. The designed control algorithm is tested and confirmed its validity using experiment and simulations by tracking the reference path of the ROUV. It is evidence that the designed control system shows quick convergence, improved steady state error and better robustness in the presence of disturbances.

Tandem configuration-containing perovskite and silicon solar cells are promising candidates for realizing a high power conversion efficiency of 30% at reasonable costs. Silicon solar cells with planar front surfaces used in tandem devices cause high optical losses, which significantly affects their efficiency. Moreover, some studies have explored the fabrication of perovskites on textured silicon cells. However, due to improper texturing, light trapping is not ideal in these devices, which reduces the efficiency. In this work, we optimized the pyramid height of textured silicon cells and efficiently characterized them to achieve enhanced light trapping. Two different kinds of perovskites, namely, Cs0.17FA0.6Pb(Br0.17I0.7)3 and Cs0.25FA0.6Pb(Br0.20I0.7)3 with wide bandgaps were conformally deposited on textured silicon cells, and the performance of these flat and fully textured tandem devices was numerically analyzed. The thickness of each layer in the tandem cell was optimized in a way to ensure a perfect current match between the top perovskite and bottom silicon subcells. The results indicated that the textured tandem configuration enhances light absorption over a broad spectral range due to the optimized pyramid height compared to flat surfaces. Eventually, the photovoltaic parameters of the proposed tandem cell were compared with the already existing structures, and our design supports large values of open circuit voltage (Voc) = 1.78 V, short circuit current density (Jsc) = 20.09 mA cm−2, fill factor (FF) = 79.01%, and efficiency (η) = 28.20% compared to other kinds of tandem solar cells.

Seeking high power conversion efficiency is always a striving pathway for many researchers to commercialize organic solar cells (OSCs). Thus, it is essential to achieve high conversion efficiency to make solar oriented devices as truly green energy resource. In this paper, we report novel tandem structures based on organic materials in which homo and hybrid schemes are utilized. The homo tandem structures involve the well-known organic materials such as P3HT: PCBM and PTB7: PCBM as top and bottom absorber layers, while the hybrid tandem structure is made by the combination of P3HT: PCBM and PTB7: PCBM, respectively. Due to different absorption coefficients, simulation results indicate that the hybrid tandem structure exhibit large values for current density Jsc = 22.60mA/cm2, open circuit voltage Voc = 0.85V, fill factor FF = 68.21%, and efficiency η = 13.96%, compared to homo tandem cell and proves to be more efficient and highly stable towards high temperatures, which indicates that the proposed structure is more suitable for practical applications.

Dye-sensitized solar cells are gaining interest in the aerospace industry, extending their applications from solar-powered drones to origami-style space-based solar power stations due to their flexibility, light weightiness, and transparency. The major issue with its widespread commercial use is the employment of expensive Pt-based counter electrodes. In this study, an attempt has been made to replace the Pt with Polyaniline (PANI)/Molybdenum sulfide (MoS2) nanocomposite. The nanocomposites i.e., PANI-0.5wt% MoS2, PANI-2wt%MoS2, PANI-5wt%MoS2, and PANI-7wt%MoS2and PANI-9wt%MoS2, have been synthesized and compared with standard Pt-based CE. Scanning electron microscopy, transmission electron microscopy, and X-ray diffraction methods have been utilized to study both surface morphology and structural composition. Fourier transform infrared has also been used to identify redox-active functionalities. Electron impedance spectroscopy and cyclic voltammetry have been employed to study electron transfer and catalytic activity. Finally, I-V testing has been conducted using a sun simulator. A maximum efficiency of 8.12% has been observed with 7wt% MoS2 in the PANI matrix at 6 µm thickness, which is 2.65% higher compared to standard Pt-based CE (7.91%). This is due to high electronic conduction with the addition of MoS2, improved catalytic activity, and the high surface area of the PANI nano-rods.

Background It is becoming imperative to develop renewable fuels such as biodiesel which are sustainable and environmentally friendly. Exploiting non-edible oils is more necessary to reduce dependency of edible oils for biodiesel production. The current study investigated biodiesel production from non-edible Salvadora persica seed oil (SPSO) and crude coconut oil (CCO) by Burkholderia cepacia lipase acting as a biocatalyst in a solvent-free system. The biodiesel yield produced from these feedstocks was compared and the effect of ethanol (acyl acceptor) vs. SPSO and CCO in various ratios on biodiesel production was determined. Results The presence of medium-chain fatty acids in majority was confirmed for SPSO and CCO while the average molecular weight was calculated as 749.53 g/mol and 664.57 g/mol, respectively. Thin Layer Chromatography indicated ethyl esters in the produced Salvadora and coconut biodiesel samples. Maximum biodiesel yield (around 70%) was obtained at 1:4 oil-to-ethanol molar ratio from both oils followed by a decline at higher ratios. The gas chromatographic analysis of Salvadora biodiesel at 1:4 molar ratio showed that the yield of individual esters was mostly of medium- and long-chain fatty acids. The analysis of coconut biodiesel at 1:4 molar ratio revealed that it consists mainly of the esters of medium-chain fatty acids. A comparison of estimated properties of biodiesel from both the parent oils with the international standard showed that it meets most of the requirements. Conclusion The study paves the way for a green route for biodiesel production and would promote the use of non-edible vegetable oils over edible ones to produce biodiesel. Further, it is a right step to use lipases in biodiesel production as compared to chemical catalysts. Ethanol, which can also be produced from biomass fermentation, can be used as acyl acceptor to produce biodiesel and this makes the process eco-friendly. Moreover, Burkholderia cepacia lipase is a good choice among lipases to get high biodiesel yields successfully from SPSO and CCO at low oil-to-ethanol molar ratios.

The Fourth Industrial Revolution begins, and policies are being formulated by economies as well as efforts are being made to meet the needs of the current times. Among other technologies which are part of Fourth Industrial Revolution, big open data is also the part of Pakistan’s digital policy framework. Scholarship is available to explore and examine the determinants of BOD diffusion and adoption, a little literature is available to understand big open data as policy innovation and its diffusion. Therefore, this study drew on Diffusion of Innovation (DOI) theory and its application to public policy innovation research to examine patterns of BOD policy innovation diffusion at government and public bodies’ level in Pakistan. These patterns are based on policy declaration timing by the governments, policy adoption timing, development of technological applications, and proactively released datasets statistics in public bodies. An Event History Analysis was carried out to examine BOD policy innovation diffusion patterns. Results showed that Federal government is the innovator for the policy innovation diffusion across different governments and subsequent public bodies. It was also found that efficacy ranking of public bodies is quite low in terms of developing BOD technological platforms and proactive release of datasets in large quantities. Therefore, government and policy-makers should focus on effective implementation of big open data policy innovation in Pakistan to equip with 21st century needs.

Neural activity that occur during motor movement, speech, thought, and various other events can be observed in the form of brainwaves composed of synchronized electrical pulses emitted from adjoining communicative neurons. Observations of these brainwaves have been made possible through neurodevices, which can detect changes in electrical and/or mechanical parameters. For decades, the field of neuroscience has been enriched by the utilization of neurotechnologies at the microscale, which has begun to gain further enhancement with the introduction of nanotechnology. For example, microelectrodes were initially used for only extracellular measurements, but over the past decade, developments have been made to also record intracellular signals. Likewise, nanoknives, which gained popularity due to their versatility, can now be used for both fabricating bio-Micro-Electro-Mechanical Systems (MEMS) and also as a neurosurgery tool. Thus, considerable efforts have been made over the years to make micro- and nanosystems reliable, accurate, and sensitive to neural activity. In the late 20th century, several sophisticated technologies, including magnetic resonance imaging (MRI), computed tomography (CT), and intracranial pressure (ICP) monitoring have been integrated with MEMS. Furthermore, existing biotechnologies are being miniaturized at both the system and component level. For example, there is a remarkable interest in the field of neuroscience to utilize microfluidic technology as a diagnostic tool using specimens such as cerebrospinal fluid (CSF). Microfluidic devices are also employed as biocompatible drug delivery systems to target cells, tissues, and organs. This paper summarizes the recent developments in micro- and nano-scale neurotechnologies, including devices, fabrication processes, detection methods, their implementation challenges, in neural stimulation, monitoring, and drug delivery. This review discusses recent developments in micro and nanotechnologies, fabrication methods, and their implementation in neuroimaging, neurostimulation, monitoring of neural activities, and neural drug delivery.

Improving the photon absorption in ultrathin-film solar cells with active layer thickness of a few micrometers is important for enhancing efficiency and reducing cost. We present a computational study of novel design consisting of ultrathin absorber layer made of gallium arsenide (GaAs) integrated with plasmonic square nanoring particles. The energy absorbed by GaAs layer is significantly enhanced with the help of plasmonic nanorings, resulting in substantial absorption enhancement of approximately 34% compared with bare active layer. For qualitative analysis, the short-circuit current density of thin-film cell is evaluated for AM 1.5 G solar illumination and is found to be 1.4 times higher compared with unpatterned solar cell structure. Furthermore, the structure is optimized by varying different parameters and materials of functional layers, yielding a photocurrent density of 30.185 mA/cm2, which is close to the Yablonovitch limit.

Burkholderia glumae and B. gladioli are seed-borne rice pathogens that cause bacterial panicle blight (BPB) disease, resulting in huge rice yield losses worldwide. However, the excessive use of chemical pesticides in agriculture has led to an increase in environmental toxicity. Microbe-mediated nanoparticles (NPs) have recently gained significant attention owing to their promising application in plant disease control. In the current study, we biologically synthesize zinc oxide nanoparticles (ZnONPs) from a native Bacillus cereus RNT6 strain, which was taxonomically identified using 16S rRNA gene analysis. The biosynthesis of ZnONPs in the reaction mixture was confirmed by using UV–Vis spectroscopy. Moreover, XRD, FTIR, SEM-EDS, and TEM analysis revealed the functional groups, crystalline nature, and spherical shape of ZnONPs with sizes ranging from 21 to 35 nm, respectively. Biogenic ZnONPs showed significant antibacterial activity at 50 µg mL−1 against B. glumae and B. gladioli with a 2.83 cm and 2.18 cm zone of inhibition, respectively, while cell numbers (measured by OD600) of the two pathogens in broth culture were reduced by 71.2% and 68.1%, respectively. The ultrastructure studies revealed the morphological damage in ZnONPs-treated B. glumae and B. gladioli cells as compared to the corresponding control. The results of this study revealed that ZnONPs could be considered as promising nanopesticides to control BPB disease in rice.

The negative effects of salinity on plant growth and physiology are well-established, which is one of the major threats to food security in semi-arid and arid regions of the world. The current research focuses on biosynthesis of copper nanoparticles (CuNPs) from a bacterial strain NST2, which was genetically identified as Klebsiella pneumoniae based on taxonomic identity of 16S rRNA gene. The strain was selected for bioprospecting of CuNPs owing to its Cu tolerance potential. The biologically-synthesized CuNPs were confirmed in culture by using ultraviolet visible spectroscopy. The material characteristics of green CuNPs were further investigated by using Fourier transform infrared spectroscopy, X-ray diffractometer, scanning electron microscopy and transmission electron microscopy, where crystallite size was ranged from 22.44 nm to 44.26 nm and particles were stabilized by various functional groups, such as carbonyl and amine groups. When 100 mg kg−1 of green CuNPs were mixed in saline soil in a pot experiment, the maize plants showed increased root and shoot length (43.52% and 44.06%, respectively), fresh weight (46.05% and 51.82%, respectively) and dry weight (47.69% and 30.63%, respectively) in comparison to control maize plants without CuNPs application. Moreover, green CuNPs at their highest treatment level (100 mg kg−1 of soil) counteracted the lipid peroxidation and oxidative damage in maize plants by promoting the activities of antioxidants and demoting the cellular levels of reactive oxygen species and ionic contents of Na+ and Cl-. Conclusively, biogenic CuNPs is an emerging and promising technique, which could replace traditional methods of salinity management in agricultural soils.

Aquilegia fragrans (AF) and Aquilegia pubiflora (AP) are the two medicinally important species of genus Aquilegia used for the treatment of various diseases and infections. This paper describes the potential of fetal hemoglobin induction activity of the methanolic extracts of AF and AP in K562 cell line. AF and AP have shown 27.147 +/- 1.376 and 32.786 +/- 1.048 percent erythroid induction, respectively at 15.625 (mg/mL) concentration which suggested that both plants can be the source of potential fetal hemoglobin inducers and may be used for the treatment of beta-thalassemia. Phytochemical analyses of both species were also evaluated by using high-resolution LC-ESI-QTOF-MS/MS techniques. A Total of thirty compounds were identified using positive and negative ionization modes. The identification was based on the matching of high-resolution masses, isotopic pattern, and MS/MS fragmentation. Several statistical analyses were performed to evaluate the distribution of compounds in both species. Identified compounds belong to various classes including flavonoids, steroids, lignans, terpenoids, benzofuran and coumarins. The established chemical fingerprints will be helpful in standardization and quality control of plant extracts.

The adulteration of plant raw materials used for the preparation of herbal drugs with foreign plant material is one of the important issues in the quality control of herbal products. Chemical fingerprinting is a well-known approach for the characterization of secondary metabolites associated with the plant species and can be used for quality control of plant material. The current study centred on the development of chemical fingerprinting of three medicinal plants of genus Anemone including A. obtusiloba, A. falconeri and A tetrasepala through identification of their metabolites using LC-ESI-QTOF-MS/MS analysis. Thirty compounds were identified by using high-resolution positive and negative electrospray- ionization (ESI) modes and MS/MS analysis. The identified compounds belong to diterpenoids, alkaloids, phenols, flavonoids and other classes and their distribution among the analysed species was studied using different statistical tools. Moreover, an LC-HR-ESI-MS/MS method was developed to detect the cross mixing of A. obtusiloba with Ziziphus jujuba. Seven chromatographically differentiative peaks confined to A. obtusiloba were selected to detect its contamination in adulterated samples. The method was able to detect as low as 20% mixing of A. obtusiloba in Z. jujuba. This study can play a significant role to manage the quality control of herbal medicines and to identify lead natural products of these plants.

The rapid development in the industrial sector has caused severe damage to the environment, which resulted in the occurrence of catastrophic disasters of high magnitude on earth. Moreover, the efforts for providing better early warnings and rescue operations during and after the disasters largely depend on communication protocol utilized for disaster management. Therefore, researchers are working to devise an efficient communication protocol for detection and communication of disasters. The communication protocol must comprise a methodology to transmit images of the disaster site effectively and facilitates communication between disaster site and disaster management centers. Presently, the disaster management is performed using terrestrial networks (using the Internet and mobile networks), space-ground networks (using satellites in different orbits), and air-ground networks (using Un-manned Aerial Vehicle and airships). Besides, the utilization of all devices in space, air, and ground can help to enhance the services for disaster management. In this work, Space-Air-Ground Integrated Network (SAGIN) is proposed to be used for disaster management. Moreover, a framework is proposed for the realization of the enhanced services using Internet Protocol (IP) for the detection and communication of disasters. Also, a comparison with the presently deployed networks is provided for comparison of services provided for disaster management.

Cadmium and drought are the most destructive of the abiotic stresses with negative consequences in terms of impaired metabolism, restricted nutrient use efficiency and disruptive photosynthesis of plants. The present study investigated the mitigation strategy of both aforementioned stresses by the application of iron oxide (IONPs) and hydrogel nanoparticles (HGNPs) simultaneously probably for the first time. IONPs were biofabricated by using a locally identified Bacillus strain RNT1, while HGNPs were produced chemically followed by the confirmation and characterization of both NPs through nanomaterials characterization techniques. Results of FTIR and XRD showed the capping of NPs by different functional groups together with their crystalline structure, respectively. SEM and TEM analysis showed the spherical shape along with the particle size ranging from 18 to 94 nm of both NPs, while EDS analysis confirmed the elemental purity of NPs. The results revealed that IONPs-treated rice plants increased biomass, antioxidant enzyme contents, photosynthesis efficiency, nutrient acquisition together with the decrease in reactive oxygen species and acropetal Cd translocation under normal and drought stress conditions as compared with control plants. Furthermore, the expression of the Cd transporter genes, OsHMA2, OsHMA3 and OsLCT1 were curtailed in NPs-treated rice plants under normal and drought stress conditions. The overall significance of the study lies in devising the NPs-based solutions of increasing heavy metal pollution and water availability challenges being faced the farmers around the world.

Chitosan is a potent biopolymer having promising antimicrobial properties against phytopathogens. Recently, engineered nanomaterials (ENMs) have gained much attention due to their potential application in the plant disease management. In this study, we reported the green synthesis of chitosan-magnesium (CS-Mg) nanocomposite and its antimicrobial activity against two rice pathogens namely Acidovorax oryzae and Rhizoctonia solani for the first time. The green MgO nanoparticles synthesized by using a native Bacillus sp. strain RNT3, were used to fabricate CS-Mg nanocomposite utilizing one-pot synthesis method. The synthesis of CS-Mg nanocomposite was further confirmed by using UV–vis spectroscopy, whereas, FTIR and XRD analysis showed the capping of CS-Mg nanocomposites by different functional groups together with their crystalline structure, respectively. Besides, SEM and TEM images revealed the spherical shape along with the particles size ranging from 29 to 60 nm. Moreover, EDS analysis confirmed the elemental purity of nanocomposite. The CS-Mg nanocomposite showed remarkable antimicrobial activity against A. oryzae and R. solani and significantly inhibited the growth as compared to non-treated control. The ultrastructure studies showed damaged structure of cell wall and internal cellular organelles after treatment with 100 μg mL−1 CS-Mg nanocomposite. The results of this study indicated that CS-Mg nanocomposite-based antimicrobial agents could be considered as promising nanopesticides against phytopathogens in plant disease management.

Pestalotiopsis versicolor is a most destructive fungal pathogen that causes twig blight disease in bayberry. For the last seven years, it is difficult to control this pathogen due to its latent infestation mode and its control through chemical fungicides is environmentally corrosive in addition to being costly. In this study, we reported the fungicidal potential of biologically synthesized zirconium oxide nanoparticles (ZrONPs) against P. versicolor for the first time. The strain used for green synthesis of ZrONPs was taxonomically identified as Enterobacter sp. strain RNT10. The production of ZrONPs in reaction mixture was confirmed through UV–vis spectroscopy analysis. Moreover, FTIR, XRD, SEM and TEM analysis showed the presence of capping proteins and crystalline nature of spherical shaped ZrONPs with particle size ranging from 33 to 75 nm. EDX spectra revealed an elemental profile of ZrONPs comprising of Zr (54.40%) and oxygen (43.49%). Biogenic ZrONPs showed substantial antifungal inhibition zones (25.18 ± 1.52 mm) at 20 μg mL−1 concentration against P. versicolor strain XJ27. Moreover, the treatment of 20 μg mL−1 ZrONPs significantly inhibited twig blight in detached leaf assay. Furthermore, imaging through SEM and TEM showed the adverse effects of ZrONPs against P. versicolor in terms of extracellular leakage of DNA and proteins. Overall, this study suggested that biogenic ZrONPs could substitute chemically synthesized antifungal agents with the specific application towards control of twig blight disease in bayberry.

Heavy metal accumulation in arable lands and water bodies has become one of the serious global issues among multitude of food security challenges. In particular, cadmium (Cd) concentration has been increasing substantially in the environment that negatively affects the growth and yield of important agricultural crops, especially wheat (Triticum aestivum L.). No doubt, nanotechnology is a revolutionary science but the comprehension of nanoparticle-plants interaction and its potential alleviatory role against metal stress is still elusive. Here, we investigated the mechanistic role of astaxanthin nanoparticles (AstNPs) in Cd stress amelioration and their interaction with wheat under Cd-spiked conditions. The AstNPs fabrication was confirmed through ultraviolet visible spectroscopy, where the particles showed characteristic peak at 423 nm. However, Fourier transform infrared, X-ray diffraction, scanning electron microscopy and transmission electron microscopy analyses confirmed the presence of stabilized spherical-shaped nanocrystals of AstNPs within the size range of 12.03–30.37 nm. The hydroponic application of AstNPs (100 mg L−1) to Cd-affected wheat plants increased shoot height (59%), shoot dry weight (31%), nitrogen concentration (42%), and phosphorus concentration (26%) as compared to non-treated Cd affected seedlings. Moreover, AstNPs-treated plants showed reduction in acropetal Cd translocation (29%) in contrast to plants treated with Cd only. Under Cd-spiked conditions, AstNPs-treated plants displayed an improved nutrient profile (P, N, K+ and Ca2+) with a relative decrease in Na+ content in comparison with non-treated plants. Interestingly, it was found that AstNPs restricted the translocation of Cd to aerial plant parts by negatively regulating Cd transporter genes (TaHMA2 and TaHMA3), and relieved plants from oxidative burst by activating antioxidant machinery via triggering expressions of TaSOD and TaPOD genes. Consequently, it was observed that the application of AstNPs helped in maintaining the nutrient acquisition and ionic homeostasis in Cd-affected wheat plants, which subsequently improved the physiochemical profiles of plants under Cd-stress. This study suggests that AstNPs plausibly serve as stress stabilizers for plants under heavy metal-polluted environment.

Novel metasurface absorber based on crossed shaped resonator placed at the top surface is proposed to exhibit enhanced absorption resonances in the entire solar spectrum. Different cases of the absorber are discussed with special emphasis on large spectral width and peak amplitude. It is found that the absorption resonances and their corresponding spectral widths can be significantly modified and widened by adding extra nanorods to the crossed shaped structure at different locations. Furthermore, the weighted absorption under the AM1.5 solar spectrum (AAM1.5) of the solar cell is also evaluated by varying the structural parameters, which reaches to ∼ 86.35%. Such high value of AAM1.5 indicates that the proposed design is highly suitable for solar cell application because it greatly enhance the conversion efficiency.

Highly porous ZIF-67 (Zeolitic imidazole framework) has a conductive crystalline metal organic framework (MOF) structure which was served as a precursor and template for the preparation of nitrogen-doped carbon nanotubes (NCNTs) electrocatalysts. As a first step, the chloroplatinic acid, a platinum (Pt) precursor was infiltrated in ZIF-67 with a precise amount to obtain 0.12 mg.cm-2 Pt loading. Later, the infiltrated structure was calcined at 700°C in Ar:H2 (90:10 vol%) gas mixture. Multi-walled nitrogen-doped carbon nanotubes were grown on the surface of ZIF-67 crystals following thermal activation at 700°C. The resulting PtCo-NCNTs electrocatalysts were deposited on Nafion-212 solid electrolyte membrane by spray technique to study the oxygen reduction reaction (ORR) in the presence of H2/O2 gases in a temperature range of 50-70°C. The present study elucidates the performance of nitrogen-doped carbon nanotubes ORR electrocatalysts derived from ZIF-67 and the effects of membrane electrode assembly (MEA) steaming on the performance of proton exchange membrane fuel cell (PEMFC) employing PtCo-NCNTs as ORR electrocatalysts. We observed that the peak power density at 70°C was 450 mW/cm2 for steamed membrane electrode assembly (MEA) compared to 392 mW/cm2 for an identical MEA without steaming.

Modifications in the physical properties of photovoltaic materials lead to enhanced conversion efficiency of a solar cell. This paper focuses on the suitable material selection for the cadmium telluride (CdTe) solar cell with special emphasis on improving the electrical parameters such as open-circuit voltage Voc, short-circuit current density Jsc, fill factor FF, and efficiency ƞ. Simulation results showed that materials having wide bandgap are more appropriate for each layer in the proposed cell compared to small-bandgap materials. Moreover, the back metal contact, which acts as electrode and also used as light reflector, usually suffers from high intrinsic absorption losses. To reduce such losses, we replaced the metal contact by a highly reflective one-dimensional distributed Bragg reflector, which increases the optical path length in greater amount over a broad span of incident angles and frequencies, and subsequently enhances the performance of the cell. The measured electrical parameters of the proposed cell under global AM 1.5G conditions are JSC = 25.036 mA/cm2, Voc = 1.065 V, FF = 87.56%, and ƞ = 23.94%, respectively.

Thin film solar cells (TFSCs) suffer from poor light absorption due to their small thickness, which limits most of their practical applications. Surface plasmons generated by plasmonic nanoparticles offer an opportunity for a low-cost and scalable method to optically engineer TFSCs. Here, a systematic simulation study is conducted to improve the absorption efficiency of amorphous silicon (a-Si) by incorporating double sided plasmonic bi-metallic (Al–Cu) nanogratings. The upper pair of the gratings together with an antireflection coating are responsible for minimizing the reflection losses and enhancing the absorption of low wavelength visible light spectrum in the active layer. The bottom pairs are accountable for increasing the absorption of long wavelength photons in the active layer. In this way, a-Si, which is a poor absorber in the long wavelength region, is now able to absorb broadband light from 670–1060 nm with an average simulated absorption rate of more than 70%, and improved simulated photocurrent density of 22.30 mA cm−2, respectively. Moreover, simulation results show that the proposed structure reveals many other excellent properties such as small incident angle insensitivity, tunability, and remarkable structural parameters tolerance. Such a design concept is quite versatile and can be extended to other TFSCs.

Chromium (Cr) concentration has been increasing substantially in the environment due to industrial and anthropogenic factors. Plants can absorb Cr and undergo unrestrained oxidation cascades, resulting in cell injury. The ameliorative role of biogenic copper nanoparticles to relieve wheat plants from Cr stress by supporting their growth is still unclear. The present work aims at the biosynthesis and characterization of copper nanoparticles (CuNPs) from a native Klebsiella pneumoniae strain, followed by assessment of wheat growth and physiological responses to CuNPs mixed in Cr-rich soil. The taxonomic rank of K. pneumoniae SN35 was established by the 16 S rRNA gene sequence analysis. The properties of biogenic CuNPs were elucidated by using UV–vis spectroscopy, FTIR, XRD, SEM, and TEM. It was found that 19.01–47.47 nm spherical shaped CuNPs were stabilized by different functional groups produced extracellularly by the strain SN35. The XRD data revealed the crystalline nature of CuNPs as a face-centered cubic structure. Different concentrations of CuNPs (0, 25, 50 and 100 mg kg−1 of soil) were added into the soil mixed with 3.5 mg kg−1 K2Cr2O7 and the pots were placed in a growth chamber for 30 days. The results revealed that the CuNPs, at 25 and 50 mg kg−1 of soil, augmented plant growth, biomass, and cellular antioxidants contents, whereas decreased the reactive oxygen species and Cr translocation from soil to roots and shoots as compared to control plants. Overall, the results revealed that the soil amendment of CuNPs could immobilize the Cr in the soil to prevent its translocation to the upper plant parts and support wheat growth by relieving cellular oxidative stress.

Background Increasing population and industrialization are continuously oppressing the existing energy resources and depleting the global fuel reservoirs. The elevated pollutions from the continuous consumption of non-renewable fossil fuels also seriously contaminating the surrounding environment. The use of alternate energy sources can be an environment-friendly solution to cope these challenges. Among the renewable energy sources biofuels (biomass-derived fuels) can serve as a better alternative to reduce the reliance on non-renewable fossil fuels. Bioethanol is one of the most widely consumed biofuels of today's world. Objective The main objective of this review is to highlight the significance of lignocellulosic biomass as a potential source for the production of biofuels like bioethanol, biodiesel or biogas. Methods We discuss the application of various methods for the bioconversion of lignocellulosic biomass to end products i.e. biofuels. The lignocellulosic biomass must be pretreated to disintegrate lignocellulosic complexes and to expose its chemical components for downstream processes. After pretreatment, the lignocellulosic biomass is then subjected to saccharification either via acidic or enzymatic hydrolysis. Thereafter, the monomeric sugars resulted from hydrolysis step are further processed into biofuel i.e. bioethanol, biodiesel or butanol etc. through the fermentation process. The fermented impure product is then purified through the distillation process to obtain pure biofuel. Conclusion Renewable energy sources represent the potential fuel alternatives to overcome the global energy crises in a sustainable and eco-friendly manner. In future, biofuels may replenish the conventional non-renewable energy resources due to their renewability and several other advantages. Lignocellulosic biomass offers the most economical biomass to generate biofuels. However, extensive research is required for the commercial production of an efficient integrated biotransformation process for the production of lignocellulose mediated biofuels.

This project was designed to evaluate the immunotoxicological effects of thiamethoxam (TMX). One-day-old broiler chicks (total of 90) were procured and maintained under standard housing conditions ...

Inevitably, the time has come that necessitates software systems to have long lasting social impact and environmental friendliness. Although sustainability related to environmental and social aspects have been well versed in the literature, software sustainability, for the way of development and as final product for use, is still not mature enough. With the increasing role of software crowdsourcing, a new working architecture for software development, in global software development (GSD) settings, has emerged challenges regarding sustainable software development and software sustainability, which are still to be elucidated. Software standards and models exist to assist co-located and global software development; however, seismic changes in the working architecture of software development as software crowdsourcing are highlighting a risk of software failure. Recently, statistics showed that only 30% of projects are successful, whereas 50% encounter challenges and the remaining 20% are absolute failures that implicate a challenge toward software success and its sustainability. This posits questions of how many IEEE and international standard organization standards exist that cover the sustainability aspects in particular to software development and how in-depth the development practices are addressing sustainable aspects in software crowdsourcing? Thus, the aim of this paper is to examine the IEEE software standards with a lens of sustainability to software crowdsourcing. After reviewing the existing IEEE standards related to sustainability, it has been observed that few standards exist which have discussed the importance of sustainability on an abstract level (energy and examining environmental influence by the computers) in software development. Moreover, standards are focusing less attention toward the sustainability of software development in the presence of new envision toward software crowdsourcing. Thus, a lack of any guideline toward sustainable software crowdsourcing is highlighted as one of the limitations in the software standards. This paper contributes to the GSD industry in two folds, first by laying down the importance and theoretical association on and around sustainable crowdsourcing, and second by highlighting that the IEEE standards, inadequacy toward the suppressing phenomena of sustainability in software crowdsourcing, if addressed adequately, can minimize the ripple effect toward software failure.

Transform-based techniques partially address challenges like robustness and the imperceptibility in image steganography. Such approaches, however, increase the memory requirement and reduce the quality of the cover image and hiding capacity. Moreover, the steganography is always coupled with cryptography to strengthen the confidentiality. This paper presents an adaptive hybrid method for image steganography procedure based on bit reduction and pixel adjustment using the fuzzy logic and integer wavelet transform technique. The fuzzy set theory provides powerful tools to represent and process human knowledge in the form of fuzzy if-then rules that can resolve difficulties in image processing arising due to the uncertainty of the data, tasks, and results. We apply a bit reduction algorithm to each byte of the data which are to hide in the cover image. This decreases the memory usage and increases the capacity. The embedding of the input text into the cover image distorts the cover image. Hence, to minimize the visual difference between the cover image and the text embedded image, an optimum pixel adjustment algorithm is applied to the text embedded image. Simulation results demonstrate the effectiveness of our proposed approach.

We numerically analyzed a simple and novel design of multi-broadband plasmonic absorber which consists of a planar array of thin gold square ring structures on dielectric/metal substrate. Several optimized designs of the metasurface screen are proposed to absorb wide range of the electromagnetic spectrum, which includes single ring, single split ring, ring inside split ring, and dual split ring resonators, respectively. Moreover, simulation results demonstrate that by changing the dimensions of the metasurface screen and the middle dielectric spacer, multi-broadband absorption resonant peaks having absorption bandwidth of about 570 nm above 50% absorption and bandwidth of about 93 nm above 90% absorption are obtained in the visible and near-infrared regime. The proposed design has potential applications in imaging and detection.

Software Engineering is a discipline that provides a systematic approach to develop software in a cost-effective manner. Successful software development is challenged by various challenges, such as varying situational contexts, conformity with standards, changing requirements, optimism of schedule, schedule pressure, software complexity, and software invisibility. Varying situational contexts are the changed circumstances that are resulted due to varying situational factors. These situational factors are the root cause of varying situations, which need to be discovered in detail. If these situational factors are left unattended, they can cause software failures. Software standards can help to deal with software failures. In this paper, we have reviewed various software engineering standards from the Institute of Electrical and Electronics Engineers Standard Association. These software engineering standards were investigated for the factors and sub-factors that can lead to varying situations among software development team members. As a result we found 12 factors grouped with 52 sub-factors that can lead to varying situations among software development team members. These resulted factors and sub-factors can act as a source for varying situations among team members. Unattended identified situational factors can lead to software failures. This paper provides a guideline for the practitioners to consider these factors and sub-factors while performing software development in order to have a successful software development.

Improving the photon absorption in thin-film solar cells with plasmonic nanoparticles is essential for the realization of extremely efficient cells with substantial cost reduction. Here, a comprehensive study of solar energy enhancement in a cadmium telluride (CdTe) thin-film solar cell based on the simple design of a square array of plasmonic titanium nanoparticles, has been reported. The excitation of localized plasmons in the metallic nanostructures together with the antireflection coating (ARC) significantly enhances the absorption of photons in the active CdTe layer. The proposed structure attained super absorption with a mean absorbance of more than 97.27% covering a wide range from visible to near-infrared (i.e., from 300 nm to 1200 nm), presenting a 90% absorption bandwidth over 900 nm, and the peak absorption is up to 99.9%. For qualitative analysis, the photocurrent density is also estimated for AM 1.5 solar illumination (global tilt), whose value reaches 40.36 mA cm−2, indicating the highest value reported to date. The impact of nanoparticle dimensions, various metal materials, shapes, and random arrangement of nanoparticles on optical absorption are discussed in detail. Moreover, the angle insensitivity is essentially validated by examining the absorption performance with oblique incidences and it is found that the solar cell keeps high absorption efficiency even when the incidence angle is greater than 0°. Therefore, these findings suggest that the proposed broadband structure has good prospect in attaining high power conversion efficiency while reducing the device cost.

This research aims to develop a simple mathematical model for performance evaluation of a thermally exposed solar parabolic trough cooker. It was done under open environmental climate conditions for domestic uses. The experimental setup consisted of a solar cooker made of polished parabolic trough stainless steel having concentration ratio 9.867. The efficiency analysis depicts that the resulted parabolic trough optical efficiency range between 53-33%, theoretical efficiency between 50-30% and the experimental efficiency between 38-5%. Additionally, the maximum water temperature achieved was 37.2 °C at the outlet of parabolic trough. However, maximum water temperature achieved by parabolic trough cooker was 53.6 °C under stagnated conditions. Furthermore, the observed cooker energy efficiency range between 6.5-0.11% and exergy efficiency was in range between 7.6 × 10−2 - 2.1 × 10−2% for direct cooking. Results found helpful for making domestic useable cooker. Keywords: Energy and exergy efficiency analysis, Mathematical model, Performance evaluation, Solar parabolic trough cooker

The advancements in communication technology have evolved the algorithms used for communication security. Recently, the Authenticated Encryption (AE) algorithms are employed for providing security services for data communication. The Advanced Encryption Standard in Counter mode (AES-CTR) with Cipher-block Chaining Message authentication code (AES-CCM) algorithm is used for providing the data security for various applications. But the AES-CCM algorithm provides limited throughput for data communication. Therefore, in this work, new architecture is proposed for increase in throughput for provision of data security for communication application. The proposed algorithm uses the AES-CTR algorithm with the Cipher-based Message Authentication Code (CMAC) algorithm for providing AE. The proposed AE algorithm is implemented on FPGA and it’s compared with the FPGA implementation of AES-CCM algorithm. The comparison results of the proposed algorithm and the AES-CCM algorithm shows that the proposed algorithm provides improvement in the consumption of the area, processing time, and throughput. The implementation of proposed AES-CMAC AE algorithm on FPGA provides a throughput of 4.30 Gbps.

Context: Vehicular Ad-hoc network (VANET) is an emerging trend that originates from the field of Mobile Adhoc Network that gained significant attention from the past few years. The communication is realized through the On-Board Unit (OBU) equipped in vehicles. The concern of VANET is to provide a safe journey to the passengers. Although its significant high mobility of vehicles may cause a loss in connection or security attacks. Objective: The aim behind systematic literature review (SLR) is to identify the diverse type of security attacks in VANET and their respective solutions to handle those attack. This study mainly focuses on VANET centric security attacks and categorizes them along with the solutions to handle these attacks. Method: By using kitchenham guideline for systematic review and PRISMA flow for study selection to ensure coverage of all relevant studies we initially came up with 403 articles. Among these studies, 84 studies were qualified to be relevant according to 4 defined research questions. After identification and categorization of VANET centric attacks, proposed solutions a mapping between attacks and solution is provided. Results: Result of this systematic literature review suggest that identifies Access Management is a major concern in VANET with 44% of selected studies followed by Privacy 28% and Sybil attack 5%. Similarly, numerous security concerns such as Message Authentication 3%, Trust Management 4% and Black Hole attack 3% receives considerably lesser attention by the research community. Conclusions: In the context of security-related solutions which technique found to be most widely used to resolve the problem. The contribution of this study is considered important because there is no such study that has provided such an extensive overview of VANET security attacks and their perspective solutions.

The performance of Single Phase Grid Connected Inverters (SPGCIs) get degraded due to several detrimental factors such as the grid voltage harmonics, the dead time effect and the turn ON/OFF of the switches and so on, which cause the harmonics at the output of Grid Connected Inverters (GCIs). Therefore, it is not easy to satisfy the harmonic standards such as IEEE 519 and P1547 without the help of harmonic compensator. In this paper, the Digital Lock-in Amplifier (DLA) based harmonic compensation is proposed, which makes it possible to extract the amplitude and phase information of the harmonics from the output current and compensate it by using a simple PI controller in a feedforward manner. In order to show the superior performance of the proposed harmonic compensation technique, it is compared with those of conventional harmonic compensation methods in terms of the effectiveness of harmonic elimination, complexity and implementation. The validity of the proposed harmonic compensation techniques is verified through the PSIM simulation and experiments with a 5kW SPGCI.

Due to the recent increasing use of nonlinear loads and Grid Connected Inverters (GCIs), the harmonics are also increasing in the grid. The detrimental effects of the harmonics in the grid include the heating in the equipment and conductors, the misfiring in variable speed drives, the torque pulsations in motors and the asynchronization of the GCIs. Therefore, the standard such as IEEE 519 and P1547 forces the GCIs to meet a certain level of output quality in terms of harmonics, phase and frequency variation. In order to inject the pure active power to the grid, the synchronization between the grid and a GCI by a highperformance Phase Locked Loops (PLLs) is essential. Several kinds of PLL methods to synchronize the GCI under the distorted grid condition have been proposed. However, their performances are significantly degraded under the distorted grid condition, especially with a DC off-set and harmonics. In this paper a novel Digital Lock-in Amplifier (DLA) based PLL is proposed to improve the performance of the PLL under the highly distorted grid condition including the power quality events. Since the proposed DLA-PLL is composed of a robust Phase Sensitive detector (PSD), it is immune to any frequency component except the fundamental and the DC off-set present in the grid can be completely rejected. The superiority of the proposed DLA-PLL is proved by the simulation and experiments by comparing it to the results obtained with the six kinds of conventional PLL methods widely used under distorted grid condition.

Various fields of manufacturing, management, and business, including technology education, software development, and information communication technology (ICT), have espoused sustainability concepts. Including sustainability concepts in technology, education can help students learn how to implement the dimensions of sustainability (economic, social, and environmental). Lack of awareness and education regarding sustainability among students can impact their competence to incorporate sustainability into technology development. Thus, the development of student competence across the curriculum of technology education for sustainability is crucial. This research aims to explore student competence development in technology education (IT, computer science, and software development) through investigating their awareness of sustainability, and to investigate how much sustainability is infused across the technology education curriculum. The case study for this research is taken from a very populous and developing country&mdash, Pakistan. First, an in-depth survey of higher education students is conducted to investigate their awareness level of sustainability. Second, qualitative document analysis is conducted, where the standard curriculum for technology education is taken and analyzed for its provision towards sustainability. A total of 159 students from various public-sector universities of Pakistan reported their awareness towards sustainability. The results show that 71% of them are unaware of the term sustainability in their respective fields, only 17% students know the basic definition of sustainability, and 12% of students have just an idea of how sustainability is related to technology education. It is also observed that the current curriculum of technology education does not sufficiently cover specific subjects or topics that can help students understand the concepts of sustainability. This study highlights the gaps in the offered curriculum for building the desired competence of students in technology education.

Energy serves as the prime mover for every country’s growth. It is the fundamental requirement of each country in the present era. As the population increases day by day the electricity demand is also increasing rapidly. Pakistan has been facing the worst energy crises in this decade since its creation. The leading cause of this deprive is the mismanagement of government and poor policies. Pakistan is a country with massive potential of clean and green renewable sources of energy, wind energy holds a significant position in it, 50 GW of wind energy farms have been installed throughout the world. In Pakistan around 1237 MW wind power farms are installed out of which a major share contained by the Sindh province with the installed capacity of about 935 MW. This paper analyses the positive steps taken in the wind power sector of our country and Sindh province. Moreover, some recommendations are also presented regarding wind power potential which will be beneficial for insertion of the huge amount of cheap power in the national grid mix to lean the looming issues of Pakistan’s energy sector.

The lifespan, power density, and transient response make supercapacitors a component of choice for the electric vehicle and renewable energy industry. Supercapacitors’ long lifecycle often makes it difficult for designers to assess the system’s reliability over the complete product cycle. In the existing literature, the remaining useful life (RUL) estimations utilize up to 50% state of health (SOH) degradation data to successfully predict the RUL of the supercapacitors with reasonable accuracy, making them impractical in terms of time and resources required to collect the data. The time to acquire data imposes restrictions on developing a data-driven RUL prediction model for the supercapacitors. The objective of this study is to reliably predict the SOH degradation curve of the supercapacitors with the availability of less than 10% degradation data to avoid time and cost-consuming lifecycle testing. This study presents a novel combination of deep learning algorithm-Deep Belief Network (DBN) with Bayesian Optimization and HyperBand (BOHB) to predict the RUL of the supercapacitors in the early phases of degradation. The proposed method successfully predicts the degradation curve using the data of the initial 15 thousand cycles (less than 6% data for training in most of the cases), which is very promising since the supercapacitor has yet to show much degradation at this stage, thus reducing up to 54% time for the development of the RUL prediction model. The proposed model shows good accuracy with percent error and root mean squared error (RMSE) ranging from 0.05% to 2.2% and 0.8851 to 1.6326, respectively. The robustness of the model is also tested by injecting noise in the training data during training.

The power quality of grid-connected inverters (GCIs) is attracting a lot of attention as the number of distributed generation systems with renewable energy sources are increased. It is well known that the harmonics present in the grid have a lot of detrimental effects on the equipment and devices connected to a power system network such as heating and derating. These effects lead to problems in terms of safety and lifespan. Therefore, harmonic standards such as IEEE 519 and P1547 suggest that GCIs should achieve total harmonic distortion (THD) of the output current that is less than 5%. However, it is not easy to achieve the current THD of GCIs that is less than 5% with only an output filter under distorted grid conditions. In this paper, a harmonic compensation method using a lock-in amplifier (LIA) is proposed. Due to the outstanding performance of the LIA, accurate information of the harmonics can be obtained. This information is used to eliminate the harmonics by the simple PI controller. To demonstrate the superiority of the proposed method, it is applied to a 5 kW single phase GCI connected to the real grid. The results obtained are compared with those of the conventional harmonic compensation methods.

Magnesium oxide nanoparticles (MgONPs) have emerged as effective antibacterial agents with unique physiochemical properties. Here, we report antibacterial activity of MgONPs produced by using Acinetobacter johnsonii strain RTN1 against rice pathogen Acidovorax oryzae for the first time. The physico-chemical and optical properties of biogenic MgONPs were elucidated by using UV–vis spectroscopy, FTIR, XRD, EDS, SEM, and TEM. Biogenic MgONPs showed substantial antibacterial activity (35.2 ± 0.61 mm zone of inhibition) against A. oryzae at 20 µg mL−1 and significantly reduced cell density (80.83% MIC at OD600) of pathogen in broth culture. The ultrastructure studies revealed the morphological disruptions in MgONPs-treated A. oryzae cells as compared to control. Hence, the MgONPs could be used to formulate a potent nanopesticide for A. oryzae.

In this study magneto-hydrodynamic convection in a half-moon shaped cavity filled with ferrofluid has been analyzed numerically. The cavity has two semi-circular bottom heaters and effect of the distance between these two heaters ( λ = 0.1 , 0.4 ) has been thoroughly investigated. Numerical simulation has been carried out for a wide range of Rayleigh number ( Ra = 10 3 ∼ 10 7 ), Hartmann number ( Ha = 0 ∼ 100 ) and inclination angle of magnetic field ( γ = 0 ° ∼ 90 ° ) to understand the flow field, thermal field and entropy generation respectively. Cobalt-kerosene and Fe 3 O 4 -water ferrofluids are used for the present investigation and considered as a single phase fluid. Galerkin weighted residual method of finite element analysis has been used for numerical solution. The code validation and grid independency test have been carried out to justify the numerical accuracy. It has been observed that increment of magnetic field reduces the heat transfer rate, whereas increment of heater distance augments the heat transfer rate significantly. Results are discussed on the basis of Nusselt number ( Nu ), Bejan number ( Be ) and shown by contours and 3D plots. It has also been found that λ = 0.4 always shows better heat transfer rate and entropy optimization.

Due to zero shading and higher packing density, interdigitated back contact (IBC) solar cells based PV modules offer low optical losses as compared to conventional PV modules. The optical losses in PV modules are mainly governed by reflection losses. In this work, loss in short circuit current density (JSC) due to reflection losses from two types of coupons, (1) back contact solar cell having glass-glass packaging with Aluminium foil as back sheet (2) back contact solar cell with conventional Tedlar as back sheet, are evaluated by incorporating two novel encapsulants, thermoplastic polyolefin (TPO) and polybutadiene ionomer (PBI), along with conventionally used ethylene vinyl acetate (EVA). The loss in JSC in case of “(1)” with TPO, PBI and EVA are found as 3.043 mA/cm2, 3.048 mA/cm2 and 3.11 mA/cm2 respectively. While, the loss in JSC in case of “(2)” with TPO, PBI and EVA are found as 2.88 mA/cm2, 2.95 mA/cm2 and 3.024 mA/cm2 respectively. Although lesser losses are observed in case of Tedlar based coupons, the results obtained from Aluminum foil based coupons are still very much comparable and its lower cost makes it a good choice to replace Tedlar in future. Moreover, the results clearly showed that TPO and PBI performs better as compared to conventional EVA with an added advantage of being less prone to encapsulant discoloration.

Organic solar cells (OSCs) have significantly reduced the overall cost of solar energy system, making solar oriented devices universally clean and green energy source. However, to make OSCs more competitive in diverse photovoltaic (PV) technologies, it is essential to attain high efficiencies by analyzing novel materials and realizing optimal arrangements of donor–acceptor materials. In this paper, we attempt to show a terse depth insight of OSCs by investigating three novel architecture schemes with special emphasis on improving the power conversion efficiency. The materials include include i) poly (3-hexylthiophene):[(6,6)]-phenyl C61 butyric acid methyl ester (P3HT:PCBM), ii) thieno [3,4-b] thiophene-alt-benzodithiophene [6,6]:-phenyl-C61 butyric acid methyl ester (PTB7:PCBM), and iii) poly{4,4′-bis(2-ethylhexyl) dithieno [3,2-b:2′,3′-d] silole-alt-5,6-difluoro-4,7-bis (4-hexylthiophen-2-yl)-2,1,3-benzothiadiazle): [6,6]-phenyl-C61 butyric acid methyl ester (PDTS-DTffBT:PCBM), respectively. Results show that the extracted performance parameters including short circuit current (JSC) = 10.88 mA/m2, open circuit voltage (Voc) = 0.82 V, fill factor (FF) = 83.52 %, and efficiency (ƞ) = 7.49 % is highest for the second scheme among others. Different intermediate layers have also been analyzed with the objective to reduce the recombination losses and enhance the power conversion efficiency of the proposed cell. The impact of temperature on the overall ղ is also presented and it is discovered that high temperature reduces the performance of the solar cell. Furthermore, the performance of the proposed structure is compared with various kinds of OSCs and it is found that our design exhibit highest efficiency. The achievement of high efficiencies in this work may accelerate the practical applications of OSCs.