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In this research paper, our main focus is to design and develop a system for classification and recognition methodology for the acknowledgment and retrieval of a Sunflower flower in the natural environment centralized on the indigenous habitat dependent on a multi-layer method. Further, we design applications for their better classification. To handle a difficult undertaking task, an interdisciplinary cooperation is displayed dependent in the latest advancement methods in software implementation in engineering and innovation implemented by machine learning. A proposed work is design to increase the strategy for utilizing the techniques of machine learning. Final utilization of the Texture Feature, RST-Invariant Feature, Pattern Classification and furthermore utilize the K-Closest Neighbor calculations is done. Firstly, the paper is proposes to study about how to gather a flower images from the natural environment along with their corresponding background and Secondly, the paper focus on the Sunflower classification utility through Machine Learning. The computerization methods through blossom utilizing through AI system for sunflower utilized the 6-types of sunflower to get the fine yielding of profoundly sprouted sunflower blooms is caught from an advanced camera with a picture. The process of recognition implemented carried with 280 pictures. This method used a recognition as well as classification of sunflower by using the k-nearest neighbor image having overall 88.52% accuracy. This designed research paper, we trained the model with information and when concealed information is achieved then the predictive model predicts the Sunflower recognition through trained data supervised technique with machine learning.

Polyacrylamide-based hydrogels are widely used as potential candidates for cartilage replacement. However, their bioapplicability is sternly hampered due to their limited mechanical strength and puncture resistance. In the present work, the strength of polyacrylamide (PAM) hydrogels was increased using titanium oxide (TiO2) and carbon nanotubes (CNTs) separately and a combination of TiO2 with CNTs in a PAM matrix, which was interlinked by the bonding between nanoparticles and polymers with the deployment of density functional theory (DFT) approach. The synergistic effect and strong interfacial bonding of TiO2 and CNT nanoparticles with PAM are attributed to high compressive strength, elastic modulus (>0.43 and 2.340 MPa, respectively), and puncture resistance (estimated using the needle insertion test) for the PAM-TiO2-CNT hydrogel. The PAM-TiO2-CNT composite hydrogel revealed a significant self-healing phenomenon along with a sign toward the bioactivity and cytocompatibility by forming the apatite crystals in simulated body fluid as well as showing a cell viability of ∼99%, respectively. Furthermore, for new insights on interfacial bonding and structural and electronic features involved in the hydrogels, DFT was used. The PAM-TiO2-CNT composite model, constructed by two interfaces (PAM-TiO2 and PAM-CNT), was stabilized by H-bonding and van der Waals-type interactions. Employing the NCI plot, HOMO-LUMO gap, and natural population analysis tools, the PAM-TiO2-CNT composite has been found to be most stable. Therefore, the prepared polyacrylamide hydrogels in combination with the TiO2 and CNT can be a remarkable nanocomposite hydrogel for cartilage repair applications.

The effect of initial conditions in a [Formula: see text] sidewall enclosure on the mean flow characteristics of a three dimensional turbulent square wall jet has been studied experimentally. The initial conditions are varied by varying the length of the nozzle; it is varied as l/ h = 10, 50, and 90, where l and h indicates the nozzle length and the side of the square nozzle, respectively. The effect of nozzle length on initial velocity profiles, velocity distribution in lateral and wall normal directions, spread rate, decay of maximum mean velocity, local Reynolds number and similarity behaviour has been studied. The wall normal spread width is higher for the nozzle length l/h = 10 in the near field [Formula: see text] but this trend completely changed after [Formula: see text]. The spread rate is found independent of the initial condition of the nozzles in the fully developed region. The decay rate of maximum mean velocity is found higher for l/ h = 10 in the region of ([Formula: see text], whereas decay rate becomes independent of the initial conditions in the fully developed region [Formula: see text]. The local Reynolds number variation is also estimated along the downstream directions for present case and found that the local Reynolds number [Formula: see text] reaches approximately 56% of the jet exit Reynolds number [Formula: see text] at [Formula: see text] for nozzle length l/ h = 10, while it is 57% and 59% of Rejet for the nozzles [Formula: see text] and [Formula: see text] respectively at the same location. The nozzle l/ h = 10 attained self similar behaviour more quickly as compared to the other nozzles. The sidewall played a significant role which pushed the fluid more towards the center resulting in a lower jet half width in the wall normal direction as compared to the corresponding case, without a sidewall. The decay rates of the maximum mean velocity for all the nozzles are estimated to be 1.08 which is in the accepted range found in the literature.

In this work, thin films (∼200 nm) of vanadium oxide were deposited on Si (100) substrate by e-beam evaporation method with low-cost V2O5 powder. Some of the as-deposited samples were annealed in t...

Roof bolts such as rock bolts and cable bolts provide structural support in underground mines. Frequent assessment of these support structures is critical to maintain roof stability and minimise safety risks in underground environments. This study proposes a robust workflow to classify roof bolts in 3D point cloud data and to generate maps of roof bolt density and spacing. The workflow was evaluated for identifying roof bolts in an underground coal mine with suboptimal lighting and global navigation satellite system (GNSS) signals not available. The approach is based on supervised classification using the multi-scale Canupo classifier coupled with a random sample consensus (RANSAC) shape detection algorithm to provide robust roof bolt identification. The issue of sparseness in point cloud data has been addressed through upsampling by using a moving least squares method. The accuracy of roof bolt identification was measured by correct identification of roof bolts (true positives), unidentified roof bolts (false negatives), and falsely identified roof bolts (false positives) using correctness, completeness, and quality metrics. The proposed workflow achieved correct identification of 89.27% of the roof bolts present in the test area. However, considering the false positives and false negatives, the overall quality metric was reduced to 78.54%.

This work presents a novel approach to utilize waste wood ash (WA) generated from incineration of fuelwood as filler in bituminous concrete mixes. The bituminous mixes containing WA was designed as per Marshall mix design, and their engineering properties were compared with the mixes containing hydrated lime (HL) at equal mass proportions ranging from 4–7%. The performance of bituminous mixes was compared using methods like static creep test, indirect tensile strength test, Cantabro test, retained Marshall stability test, active and passive analysis. The economic and environmental feasibility of both types of mixes were also analyzed by comparing their cost and greenhouse gas emission. Additionally, the mastics containing b oth fillers at the filler-binder ratio in the range of 0.6–1.2 were prepared and their viscoelastic properties, as well as rutting (after short-term ageing) and fatigue (after long term ageing) resistance, were analyzed using multiple stress creep and recovery (MSCR) and linear amplitude sweep (LAS) tests respectively. Mastics containing WA displayed higher fatigue life and marginally lower rutting resistance than HL mastics. Irrespective of the type of filler, rutting, and cracking resistance of both bituminous mixes were found to increase with the quantity of filler. At optimum filler content, WA mixes exhibited 10, 30, and 41% lower moisture, cracking, and raveling resistance than conventional HL mixes. However, WA mixes also consumed relatively lower optimum binder content and found to be 7% more cost-effective and 62% more environmentally friendly than HL mixes. The overall conclusions of this study ascertain the utility of WA as an alternative filler in bituminous concrete.

In this work, a simple and viable method of green synthesis of multi-walled cobalt doped arginine carbon nanotubes (CNT’s) by chemical precipitation method using arginine amino acid is reported. The atomic force microscopy confirmed that metal ions present in a branched fashion on the surface of Co-doped arginine CNT’s and the obtained particle with diameter 20 nm well dispersed on the carbon nanotubes. The TEM analysis indicates the interlayer separation between the two adjacent carbon walls is estimated to be about 0.34 nm. The electron diffraction patterns indicate that the tube has nearly identical chirality for all of the concentric graphitic layers, as a zigzag-type MWCNT. The SEM analysis predicted tube like morphology and strain is existed on the surface of the CNTs. The Raman spectra confirmed the armchair (n = 8 to 11) multi-walled nanotubes with this chirality are assigned as a semiconducting type of nanotubes. The thermal property was studied by thermogravimetric analysis, differential thermal analysis and predicted the 27.81 % purity in CNTs.

Vasculitis is chronic inflammation resulting in necrosis of blood vessels due to narrowing or occlusion of the lumen. Here we present a case of 28 yrs old woman suffering from medium size vessel vasculitis since childhood. The patient had purulent skin lesions at lateral aspect of lower limbs, fatigue and pain all over the body. There was complaint of bluish discoloration of extremities, especially in winter season. The patients had history of similar skin lesions in past which were treated by allopathic treatment, but this treatment failed in meeting the expectations of patient. These lesions were not responding to the contemporary treatment since a year. The Ayurvedic diagnosis of the case was established as Siragatavata complicated with Dusta Vrana (~infected wound). She was treated with Vrana Prakshalana (doucing of skin ulceration) with Triphala Kwath for initial 15 days followed by Virechan Karma (purgation therapy) with Tilvaka Ghrita in 20 g dose. Erandmooladi Niruha Basti (enema mainly with decoction) with Bala Taila (oil) Anuvasan Basti (enema with oil) for eight days in Yoga Basti Krama (eight days order of enema) was administered after Virechana Karma. The Ayurvedic oral drugs [Ashwagandhaveleha-10 g, Jwarhar Kashaya- 40 ml, Shatavari Churna (powder)-3 gm, Vidanga Churna-2 g Kaishor Guggulu-500mg and Shilajatwadi Loha-500mg] twice a day for 12 months were also administered in the case. Skin lesions healed after a month of treatment and there was no relapse in more than 18months follow up. Patient was lean and thin and underweight at the beginning of the treatment. There was 4 Kg increase in weight during the treatment. There were no complaints of paresthesia, pain and fatigue after 18 months of treatment. No bluish discoloration was noted during this period. Presently patient is stable with Ayurvedic medications. The case study shows that medium size vessels vasculitis may be managed with Panchakarma procedures and Ayurvedic medication with satisfactory outcome. However, large sample studies are required for definitive conclusion.

Roof bolts are commonly used to provide structural support in underground mines. Frequent and automated assessment of roof bolt is critical to closely monitor any change in the roof conditions while preventing major hazards such as roof fall. However, due to challenging conditions at mine sites such as sub-optimal lighting and restrictive access, it is difficult to routinely assess roof bolts by visual inspection or traditional surveying. To overcome these challenges, this study presents an automated method of roof bolt identification from 3D point cloud data, to assist in spatio-temporal monitoring efforts at mine sites. An artificial neural network was used to classify roof bolts and extract them from 3D point cloud using local point descriptors such as the proportion of variance (POV) over multiple scales, radial surface descriptor (RSD) over multiple scales and fast point feature histogram (FPFH). Accuracy was evaluated in terms ofprecision, recall and quality metric generally used in classification studies. The generated results were compared against other machine learning algorithms such as weighted k-nearest neighbours (k-NN), ensemble subspace k-NN, support vector machine (SVM) and random forest (RF), and was found to be superior by up to 8% in terms of the achieved quality metric.

Carboxymethyl cellulose (CMC) is the most versatile cellulose derivative having several industrial applications such as mineral processing, pelletization process, oil drilling, surface modification...

Medicinal leech therapy or Hirudino therapy have roots back in ancient civilization. It was a prevalent form of therapy in various ailments. The novel Ayurveda text Sushruta Samhita devoted a complete chapter on hirudino therapy. In the early 20th century this therapy had a major setback due to origin and evolution of antibiotics. There was a discontinuity in the flow of knowledge about this therapy. Then, resumed and revived after few recent decades, due to its contribution in reconstructive surgeries. During this period, the research work on various aspects have been conducted. The present paper summarizes the various aspects of medicinal leech therapy both from Ayurveda text and the present knowledge and to enable the fraternity to use the both source for benefits of humankind.

To provide the best return on investments it is often required to assess the suitability of a site for installation of solar photovoltaic panel and quantify shading and atmospheric losses. The shading analysis is generally done using light detection and ranging or 3D geographic information system-based approaches which are cost-effective only for large-scale analysis. In several cases, particularly in developing countries, LiDAR data or 3D GIS are not available. In this study, a terrestrial image-based system is developed to accurately estimate solar insolation at a place. The positions of obstructions obtained using captured images are integrated with sun position model to provide solar insolation and optimal solar panel orientation. To further refine the result, the effect of sky conditions on the obtained solar insolation is also considered at monthly and yearly scale. About 40% reduction in solar insolation is observed due to shading which rose to 51% when the atmospheric conditions were included in the analysis of the selected sites. Further, an approach to estimate solar insolation over an area using some discrete point location is also presented and demonstrated. Results from 30 sites show that the obtained error in insolation estimate over an area is within 4%.

The study aims to conduct experimental investigations towards an integrated coolant and cutting tool based strategies for sustainable machining of Ti6Al4V alloy. Laser textured cutting tools were used under vegetable oil based MQL, and alumina suspended DI water based nMQL environments. The results were compared with plain and textured tools under dry condition with the same machining parameters. A detailed experimental plan was executed to conduct the series of experiments considering machining parameters, texture parameters and machining environment collectively. The MQL and nMQL parameters were selected based on spreadability of droplets at varying air pressure and flow rate. The results have shown a reduction in cutting forces, apparent friction coefficient, contact length, tool wear and chip adhesion over the rake face with textured tools under MQL environment. Nano fluid based cooling has a limited advantage over the range of cutting speeds and feeds as alumina nanoparticles get accumulated in the textured space. Reduced curling radius is obtained with textured tools due to the intense heat generated and associated interface multipoint micro-cutting (IMP-μC) mechanism.

The present study attempts a conjugate analysis of satellite-based remote sensing, gravity, and magnetic data for evaluation of structures and tectonic for new insights on Kimberlite emplacement ar...

An open label, randomized, comparative, interventional pilot study was done to assess the effect of Lekhana Basti (medicated enema) and Rechana Nasya Karma (Errhine therapy) in the management of Sthoulya with special reference to obesity. In the study 30 clinically diagnosed patient of either sex were randomly divided into two groups. In Basti group, Lekhana Basti in Karma Basti manner was given for 30 days. Anuvasana Basti (enema with Triphaladi Taila) in the dose of 120 mL and Asthapana Basti (enema with Triphaladi decoction etc.) in the dose of approximately 960 mL was given. In Nasya group, Rechana nasya on alternate days was given with Triphaladi (oil) in the dose of 0.5 mL per nostril for total 28 days. The patients were assessed on objective criteria such as such as weight, chest circumference, mid-arm circumference, mid-thigh circumference, triceps skin fold thickness, sub-scapular skin fold thickness, abdominal skin fold thickness, waist-hip ratio and lipid profile. It was observed that Basti group was a better intervention in providing relief, however there intergroup standard deviation was low on most of the variable expect the lipid profile. The results suggest that the Nasya Karma may be developed as a better practical approach in obesity management.

The pandemic spread of corona virus disease 2019 (COVID-19) has become a global threat. No cure is available for this condition till date. Ayurveda, may come to rescue in these times of COVID -19 spread. In this review we have analyzed that the COVID-19 has analogy with the Rajayakshma (∼a wasting disease indicating suboptimum immune response) and the established treatment of Rajayakshma disease can be proposed for preventive as well as curative purpose.

Various compositions of hexagonal boron nitride (h-BN) doped ceramics in the compound [(70-x)BaCO3-30TiO2-xBN] (x = 0, 1, 3, and 5) were prepared using conventional solid-state reaction method. X-ray diffraction (XRD) analysis showed the formation of bulk and opaque samples that confirmed the highly crystalline nature of these ceramics. The structural, surface morphological and elemental analyses were carried out in brief by employing the distinct characterization techniques. To obtain the information about the bond formation among the used oxides/nitride in these composite ceramics the FTIR tests were performed. Scanning electron microscope (SEM) was used to record the surface features at a desired magnification of the ceramic samples along with their grain and grain boundary distributions. The energy dispersive X-ray analysis (EDAX) was also carried out in detail for the Gold (Au) coated ceramic samples and determines the average elemental compositions.

As a newly exfoliated magnetic 2D material from hematite, hematene is the most far-reaching ultrathin magnetic indirect bandgap semiconductor. We have carried out a detailed structural analysis of hematene via prefacing strain by means of first-principles calculations based on density functional theory (DFT). Hematene in the pristine form emerges out to be a magnetic semiconductor with a bandgap of 1.0/2.0 eV for the majority/minority spin channel. The dependence of magnetic anisotropy energy (MAE), TC, and the bandgap on compressive and tensile strains has been scanned exclusively. It is examined that TC depends firmly on the compressive strain and increases up to 21.1% at a compressive strain of 6% whereas it decreases significantly for tensile strain. The MAE is negatively correlated with the tensile and compressive strain. The value of MAE for all compressive strain cases is more than that of the pristine hematene. These results summarize that the studied 2D hematene has broad application prospects in spintronics, memory-based devices, and valleytronics.

From a materials standpoint, biological cells can be regarded as nanomaterial factories, perfected by evolution to execute seemingly complex functions in a seamless, energy efficient manner. This a...

In this work, the thin films of vanadium oxide on Si substrate were deposited by RF sputtering and pulsed laser deposition method. The as-deposited samples were annealed in argon atmosphere at 500°...

The present study is an attempt to integrate the laser surface modification techniques with PVD-coatings. AlTiN and AlCrN coatings were deposited on different laser shock peened (LSP) and laser surface textured (LST) WC/Co surfaces. The developed surfaces and PVD coatings were characterized for surface morphology, elemental composition, surface topography, substrate/coating phases, and adhesion behavior. Tribological tests were performed to understand the friction and wear performance of developed surfaces against Ti6Al4V counter pair at varying sliding speeds. Tribo test results revealed that the coatings deposited on laser processed surfaces are helpful in reducing the coefficient of friction (COF) and wear loss. The associated wear mechanisms are discussed with the help of proposed wear models. For laser textured surfaces, the experimental evidence of texture induced micro cutting mechanism has been reported. The generation of weaker carbides for LSP surfaces reduced the coating adhesion and resulted in poor tribological performance. For machining of Ti6Al4V, improved performance of coated LST surfaces was achieved. Apparent friction coefficient and flank wear were reduced by 64% and 65% respectively.

In this manuscript, coupled and Schrodinger equations have been used for theoretically calculating and comparing XPM-induced crosstalk due to 3OD in SCM-WDM transmission system. XPM-induced crosstalk increases from (-95dB to-73dB) using Coupled equations and from (-117dB to-86dB) using Schrodinger equation when modulation frequency is increased from 0.5 to 5GHz. It is observed that XPM induced crosstalk is increased from (-90 dB to-67 dB) using Couple equation and from (-120 dB to-79 dB) using Schrodinger equation when transmission length lies between 5 to 50 km. XPM induced crosstalk remains between (-70 dB to-45 dB) using Couple equation and between (-110 dB to-60 dB) using Schrodinger equation when power lies between 0.2 to 2 mW. It has been deduced that Schrodinger equation gives less non-linear crosstalk induced by XPM in comparison with coupled equations in SCM-WDM transmission system.

In this paper, a physics-based analytical model for III-V based high electron mobility transistor (HEMT) is proposed. The variations in permittivity due to the change in thickness of the semiconductor layers from their bulk counterpart to the nanoscale are integrated into the model for the first time. In addition, the influence of trap density on channel charge is considered in the model. The contribution of two lowest energy levels is also considered, widening the applicability of the model for various device designs. The consistency of the proposed model is demonstrated by comparing modeled results with the experimental results of different device designs fabricated from different materials, including GaN.

Tool surface modification strategies are expected to achieve energy efficient dry cutting pertaining tribological advantages of textured surfaces. Current work focuses on both experimental and finite element based approaches to understand the effect of textured and coated textured tools on machining performance of Ti6Al4V alloy. Novel chevron textured tools were fabricated using nanosecond fiber laser and further coated with PVD-TiAlN coating. 2D FE simulation studies for turning with uncoated textured and TiAlN coated-textured tools were performed and compared with plain and coated-plain tools. The effectiveness of the textured tools is evaluated in terms of cutting forces, average friction coefficient, tool-chip contact length, chip disentangling behavior, and shear stresses between coating-substrate adhesions. Results confirm that the coated textured tool is helpful in machining performance improvement of Ti6Al4V alloys even at comparatively higher cutting speeds and feed. The concept of interface multipoint micro-cutting (IMP-μC) at varying machining speeds was observed from FE simulations and verified from experimental results.

Corrosion in reinforced concrete structure is a serious problem that leads to unexpected premature deterioration of reinforced concrete structure. One of the causes of the steel corrosion is due to ingress of sulphide ions at the surface of reinforcing bars in concrete. This study is an attempt to estimate corrosion effect of sulphuric acid solution through the parameters such as corrosion current density, corrosion rate and weight loss. This experimental study is carried out with the help of three-electrode electrochemical system. The study involves 12 mm o and 8 mm o steel bars embedded in cylindrical concrete specimen kept in sulphuric acid solution. Formation of a brown ring and cracks is observed near the bottom. The corrosion rate is found to be very high, when the specimens are immersed in concentrated sulphuric acid solution. The effect of diameter of bar to corrosion rate is observed to be negligible. Rusting is more in that portion of bar which is near the top; this may be due to its proximity to counter electrode and no provision of cover at this portion.

The main objective of present work was to synthesize sodium doped polycrystalline hydroxyapatite NaHAp (NaOH-HAp) powder by employing wet chemical precipitation method and its composites with alumina (Al2O3; 0, 10, 40, 70 wt%) using a scalable solid-state reaction method. Detailed investigations of NaHAp and its composites using X-ray powder diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, Raman spectroscopy, UV–visible spectroscopy, scanning electron microscopy followed by energy-dispersive X-ray spectroscopy and sensing behaviour is carefully described. XRD results exhibited major and minor phase of HAp, Ca2P2O7 and NaOH for NaHAp sample while for all fabricated composites of HAp–NaOH–Al2O3 and revealed the major phase of hibonite CaO(Al2O3)6 along with secondary phases of Ca2P2O7, Na4[Al(PO4)2(OH)], Na3Al(OH)(HPO4)(PO4), NaAl3(PO4)2(OH)4 and NaOH. The crystallite size of NaHAp-based composites was also determined and lies in the range of 200–2800 nm, which is larger than that of Al2O3. FTIR and Raman spectroscopic studies reveal the bonding formation of P–O, O–P–O and Al–O due to intramolecular interaction of Na4(Al(PO4)2(OH)), Na3Al(OH)(HPO4)(PO4) and NaAl3(PO4)2(OH)4 in the HAp–NaOH–Al2O3 composite, while bonding formation of Al–O–H recognized to intermolecular interaction in between Al with H atoms of Na4(Al(PO4)2(OH)), Na3Al(OH)(HPO4)(PO4) and NaAl3(PO4)2(OH)4. The SEM and energy dispersive spectroscopy analysis revealed the presence of all constituent elements of used chemicals which also validate the purity of used materials. It is concluded that the fabricated sensor (60 NaHAp–40 Al2O3) shows lowest response and recovery time, 4 and 3 s for the 0.5 vol.% concentration of the LPG. Therefore, among all composites, this fabricated composite can be used for LPG gas sensing applications.

The present work investigates the effect of cryogenic coolant on machining of Ti6Al4V alloy with plain and laser textured carbide cutting tools. The textured tools were used for machining under dry and cryogenic cutting conditions, and the machining results were compared with plain tools. Cutting forces, average tool temperature, interface temperature, and tool wear were predicted with the help of FE simulations. Results show a reduction in average cutting temperature for textured tools under cryogenic conditions. FEM simulations predicted the microscopic wear inside and around the textures and nearly 50% reduction in microscopic wear has been obtained for textured tools under cryogenic cooling.

World environmental pollution is having direct and visible influence of construction industry. Relatively, 10 quintal of CO2emitted by the manufacturing of 10 quintal of ordinary portland cement (OPC), which accounts almost seven percent of the global CO2 emissions. Averagely, ten thousand million cubic meter of concrete is produced yearly. Byproducts like rice husk ash (RHA), fly ash, blast-furnace slag, metakaolin and silica fume will be able to utilize as supplementary cementitious material because of their pozzolanic behavior. Rice husk cannot be used as animal’s feed due to the low nutritional value. Neither can it be discarded as landfill nor by burning because it arise a great environment challenge. By converting rice husk into rice husk ash (RHA), it can be used in concrete as a fractional substitution of cement because of high silica quantity in RHA. In this present paper, the result of some authors with the use RHA as a fractional substitution of cement on the properties of concrete like workability, permeability, compressive and tensile strength are reviewed.

Effect of texture shapes and texture area density for machining applications is a potential topic of investigation. However, it is difficult to fabricate perfect dimensions by using available micromachining techniques. Finite element simulations can be an effective way to understand the effect of texture density, texture depth and different geometric shapes on machining performances. The present study deals with the 3D finite element investigations of different texture shapes to predict cutting forces during machining of titanium alloy under dry condition. Available Johnson–Cook material model parameters have been investigated to select suitable parameters for 3D finite element studies in titanium machining. Different geometrical shapes (circular, square, triangular and elliptical shape) with the constant area are modeled at the rake face of cutting tools to incorporate textures. The effects of texture shape are studied for variation in cutting forces with different texture area density and depth. The effect of texture shape is found to be less influential for dry cutting however area density is found to have the most dominant effect on cutting forces. Further, the linear regression model for tool–chip contact length has been developed for the textured and untextured tools under different machining parameters. The developed model has incorporated the chip serration effect (serration peak and valley heights) in the contact length model. The contact length model for the textured tool has been developed for the first time, and the contact length variation has been compared with the plain tools. The results reveal that textured tools have limited applicability for dry cutting of titanium alloys. Further, the associated mechanism of contact area reduction for textured tools has been found to be not applicable at increased feed and cutting speeds due to chip embedment into textured space.

Before installing Photovoltaic (PV) panels at a place it is important to estimate the solar potential of the place. Most approaches available in literature do not consider the presence of surroundi...

Bio-inspired engineering applies biological design principles towards developing engineering solutions but is not practical as a manufacturing paradigm. We advocate 'bionic manufacturing', a synergistic fusion of biotic and abiotic components, to transition away from bio-inspiration toward bio-augmentation to address current limitations in bio-inspired manufacturing.

We performed density functional theory based calculations on Si 60 cage and analyzed the effect the substitution of single Al or P atom. We have explored and compared various electronic properties of Si 60 , Si 59 Al and Si 59 P cages. The density-of-state curves reveal that the substitution of Al (or P) creates additional energy level such that the frontier orbital gap is decreased, increasing its conductivity. The lower ionization energy of Si 59 Al and higher electron affinity of Si 59 P suggest the easy injection of holes and electrons, respectively. These findings clearly demonstrate that Si-nanoclusters mimic the properties of their bulk analogues.

Owing to increased demands of more efficient cutting tools for machining difficult to cut materials and environment friendly cutting operations, laser textured tools have become necessary. The characterization and machining studies with such laser textured tools coated with hard ceramic coatings are the prime motivation for this present work. The main aspect of the study is to evaluate two different PVD coated (AlTiN and AlCrN) laser textured tools. In the first stage, laser textured tools were prepared with novel chevron shaped textures on tool rake face using nanosecond pulse laser. This stage is followed by PVD coatings of AlTiN and AlCrN coatings by cathodic arc evaporation (CAE) technique. Coating characterization studies were conducted considering coating morphology, surface roughness, coating elemental analysis and phase analysis of coated and coated textured tools. The performance of the different tools thus manufactured was evaluated by carrying out suitable turning experiments on cylindrical Ti6Al4V work material under dry cutting environment. Machining results were evaluated in terms of cutting force, flank wear progress, rake surface analysis, and chip underside study. Further, static diffusion couple test (SDCT) has been conducted to understand diffusion wear mechanism in plain and textured tools. A new concept of derivative cutting or interfacial multipoint micro-cutting (IMP-μC) on chip underside surface due to texture patterns and a reduction of derivative cutting due to coatings on the textured tools have been proposed.

In this article, we have presented a comparative analysis of XPM crosstalk due to 4OD parameter in SCM-WDM link. Non-linear Schrodinger equation (NLSE) and coupled equations have been used to evaluate performance of the communication link. Results obtained using both equations have been compared and it has been concluded that 4OD parameter contributes significant amount of XPM crosstalk. It is deduced that XPM crosstalk due to 4OD parameter grows with increase in modulation frequency. XPM crosstalk due to 4OD parameter lies in the range of −180 dB to −105 dB employing coupled equations whereas it varies between −270 dB and −142 dB employing NLSE when modulation frequency increases from 0.2 to 5 GHz. XPM crosstalk lies between −209 dB and −158 dB employing coupled equations whereas it increases from −239 dB to −172 dB employing NLSE as transmission length increased from 1 to 50 km. XPM crosstalk varies from −175 dB to −145 dB using coupled equations while it lies in the range of −210 dB to −156 dB using NLSE when optical power varies from 0.1 to 2 mW.

Objective: To deposit the highly crystalline thin film of vanadium pentoxide on Si substrate. Method: In this work, we deposited vanadium oxide thin films by RF sputtering setup. These deposited thin films were annealed at 500°C for 1 hour in argon atmosphere. Grazing Incidence X-Ray Diffraction (GIXRD), Raman Spectroscopy and Fourier Transform Infrared Spectroscopy (FTIR) are used to analyze structural properties of as-deposited and annealed thin films of vanadium oxide. Finding: GIXRD spectra of annealed film revealed that highly crystalline thin film of vanadium pentoxide (V2 O5 ) is obtained. The texture of the film is oriented along c- axis, perpendicular to the surface of the Si substrate and it’s a, b axis are parallel to the surface of substrate. Raman Spectroscopy and FTIR results confirmed the layered structure of the annealed vanadium pentoxide thin film. After post annealing, the highly crystalline and layered structure of V2 O5 thin film on Si substrate is obtained. Applications: Vanadium pentoxide thin films are used in electrochromic devices, lithium batteries, and energy storage devices and as toxic gas sensors. Keywords: Vanadium Pentoxide (V2 O5 ), Grazing Incidence X-Ray Diffraction (GIXRD), Raman Spectroscopy, RF Sputtering

The present investigation focuses on the structural properties and magnetic response of Co, Mn and Co-Mn doped TiO 2 nanoparticles (within 3% dilute doping) along with their optical and electrical studies. X-ray diffraction (XRD) patterns for all these samples show the formation of tetragonal TiO 2 anatase phase with no extra impurity phases. Further, Raman bands at 143 cm −1 , 396 cm −1 , 516 cm −1 and 639 cm −1 also confirm the anatase phase in these samples. Diamagnetic response has been observed in pure TiO 2 nanoparticles. However, room temperature (RT) ferromagnetism has been observed with Co and/or Mn doping which gets enhanced further with codoping of Co ions. The observed ferromagnetism has been attributed to the formation of shallow levels with doping/codoping. The Co and/or Mn-doped TiO 2 nanoparticles are referred as diluted magnetic semiconductors due to their combined semiconducting and ferromagnetic response. UV-Vis spectra show the band gap of these samples are in the range of 3.03 eV–3.24 eV and a reduction in band gap is observed after codoping. The temperature dependent electrical conductivity measurements also show an enhancement in conductivity after codoping at RT.

The electronic properties of nanoclusters, such as Si 60 cage, are remarkably changed by substitution of heteroatom such as Al or P. How do such impure Si 60 cages behave when brought together to form a complex? To address this, we have performed DFT and TD-DFT based calculations on Si 60 Si 60 dimer and Si 59 Al Si 59 P complex. We have explored various electronic properties of Si 59 Al Si 59 P complex and compared with those of Si 60 Si 60 dimer. We notice that the bonding along with binding energies of cages in the complex is slightly different than that of dimer. The higher dipole moment and smaller energy gap of the complex compared to dimer suggest its increased polarity and conductivity. The density-of-state curves reveal that the frontier orbitals of the complex are slightly shifted relative to dimer such that their energy gap is decreased. The electronic excitation analyses suggest that the electronic transition in Si 59 Al Si 59 P complex takes place via charge transfer (CT) mode, and the strength of this CT interaction is much larger than that of Si 60 Si 60 dimer. This is confirmed by larger oscillator strength, larger distance between the centroid of hole and electron as well as larger Δ r index value. We believe that these findings might be useful in the application of Si-nanoclusters in the field of molecular electronics and nanoelectronics.

In this work, the results of DFT-based calculations on the structures, stabilities, vibrational, electronic, and hydrogen storage behavior of (CaO) n rings are presented and discussed systematically. The equilibrium ring structures of Ca–O clusters for n = 2–5 are found to be stable. Vibrational frequencies and IR intensities further support the enhanced stability with an increase in the size of Ca–O clusters. The HOMO–LUMO surfaces and their derived parameters are used to explain the electronic properties of the titled systems. For efficient hydrogen storage, metals especially, the transition metals with large cohesive energy (CE) suffer from the problem of cohesion as it is expected that the adsorption energies of metal decorated absorbents should be larger than the CEs of metal. In order to avoid this, hydrogen adsorbed directly on the absorbents is preferred. Due to relatively smaller CEs of the s-block metals, hydrogen adsorbs directly on the cluster which indeed solves the problem of cohesion. The hydrogen storage capacity of (CaO) n clusters, considering hydrogen adsorption on (CaO)4 and (CaO)5 rings is studied. The outcomes appear to give meaningful and satisfactory results. Thus the present work is expected to lead further the applications of small clusters for easy, efficient, and eco-friendly hydrogen storage.

Mutilation of various industrial devices like rechargeable-batteries, magnetic-recording heads from corrosion and wear can be protected by carbon coatings on nickel surface. This article presents a comprehensive study of the corrosion, magnetic and tribological behaviour of electrophoretically deposited Ni with the carbonaceous reinforcements, i.e. diamond (Ni-D), carbon nanotubes (Ni-CNT) and graphene (Ni-Gr). Enhanced corrosion resistance of Ni-D coating (1920 Ω cm 2 ) than that of pure Ni (552 Ω cm 2 ) and permanent magnetism with higher magnetic coercivity (413.56 Oe), compared to that of Ni-CNT (132.91 Oe), Ni-Gr (124.63 Oe) and pure Ni (129.07 Oe) coatings, is linked through the interfacial anchoring via distribution of the reinforcements. Enhanced magnetic coercivity and remanence of Ni-D coating is attributed to a wider domain wall width (1.65 μm) which has enhanced magnetostatic energy per unit area near the surface (3.16 erg/cm 2 ) compared to that of CNT (2.25 erg/cm 2 ) and graphene (0.94 erg/cm 2 ). Moreover, compressive stress (−611 MPa) existing in Ni-D coating have shown to seal the micro-cavities restricting the onset of corrosion and wear. With an enhanced corrosion resistance, magnetism and frictional resistance (reduced coefficient-of-friction, scratch wear volume and high scratch hardness), Ni-D coatings can be effectually applicable for batteries, marine, automotive and aerospace industries.

A large amount of waste coconut shell is generated in India from temples and industries of coconut product and its disposal need to be addressed. Researchers have proposed to utilize it as ingredient of concrete. This experimental investigation was aimed to quantify the effects of replacing partially the conventional coarse aggregate by coconut shell to produce concrete. The research work was divided into two parts. First part was aimed to observe the effect of such replacement on compressive strength and density of concrete. In the second part, the aim was to find out the additional quantity of cement required to compensate for reduction in strength of concrete resulted due to this replacement. It was found that with increasing proportion of coconut shells, there is decrement in compressive strength. Results revealed that with 40% replacement of conventional coarse aggregate by coconut shell, 7 days compressive strength of concrete decreased by 62.6%; whereas decrease in 28 days compressive strength was only 21.5%. 40% replacement makes the concrete lighter by 7.47%. Further, it was revealed that for mix design of concrete of 20 N/mm 2 characteristic strength, no additional cement is required for 5% replacement and only 3.6% additional cement was required for 10% replacement. The results confirm that although there is an increase in cost due to additional cement requirement, the advantages being many, including efficient utilization of waste coconut shell, reduction in natural source depletion etc , the use of coconut shell in concrete seems to be a feasible option. Such study will help to arrive at final decision regarding quantity of coconut shell for replacing conventional aggregates in concrete production.

We perform the linear stability analysis of a new model for poromechanical processes with inertia (formulated in mixed form using the solid deformation, fluid pressure, and total pressure) interacting with diffusing and reacting solutes convected in the medium. We find parameter regions that lead to spatio-temporal instabilities of the coupled system. The mutual dependences between deformation and diffusive patterns are of substantial relevance in the study of morphoelastic changes in bio-materials. We provide a set of computational examples in 2D and 3D (related to brain mechanobiology) that can be used to form a better understanding on how, and up to which extent, the deformations of the porous structure dictate the generation and suppression of spatial patterning dynamics, also related to the onset of mechano-chemical waves. UCR::Sedes Regionales::Sede de Occidente UCR::Vicerrectoría de Docencia::Ciencias Básicas::Facultad de Ciencias::Escuela de Matemática

Wireless sensor networks (WSN) offer great expertise that club the sensing, execution, communication, and network technology along with microelectronics and micro-mechanical devices together to study the environment. It is a new concept and a consequence of few steps in the communication field. If the original prospect of this new network works according to the planned concept, it will recover the examining and control systems used these days in the environment for consumer, medical, industries, and military sectors. The wireless technology gives the advantage of decrease in cost that cabling operation has in recent systems and also makes it possible to perform measurements in unreachable places. Many applications can work on the concept of this technology.

Mapping of sensitive species in environments such as upland swamps is important for management of anthropogenic impacts. However, the task is challenging due to the inherently complex distribution of species. Unmanned aerial vehicle (UAV) based remote sensing has the potential to map such complex environments. In this study, an integrated UAV and light detection and ranging (UAV-LiDAR) system was employed to map swamp and non-swamp vegetation in a complex upland swamp environment. The paper details the process of data acquisition, pre-processing, extraction of LiDAR metrics, dimensionality reduction, and different classification methods. Independent component analysis with support vector machine (ICA+SVM) produced the best classification results with a 69.9% overall accuracy (OA) and 0.62 kappa coefficient (k). The OA and k accuracy further improved to 73.6 % and 0.67 by adding high resolution optical (RGB) data along with the LiDAR data. The UAV-LiDAR technology offers an effective approach to distinguish between swamp and non-swamp vegetation communities.

10 pags., 5 figs., 1 tab. -- Open Access funded by Creative Commons Atribution Licence 4.0, We report novel data on ion-pair formation in hyperthermal (30–800 eV) neutral potassium collisions with neutral pyrimidine (Pyr, C4H4N2) molecules. In this collision regime, negative ions formed by electron transfer from the alkali atom to the target molecule were time-of-flight mass analyzed and the fragmentation patterns and branching ratios have been obtained. The most abundant product anions have been assigned to CN− and C2H− and the electron transfer mechanisms are comprehensively discussed. Particular importance is also given to the efficient loss of integrity of the pyrimidine ring in the presence of an extra electron, which is in contrast to dissociative electron attachment experiments yielding the dehydrogenated parent anion. Theoretical calculations were performed for pyrimidine in the presence of a potassium atom and provided a strong basis for the assignment of the lowest unoccupied molecular orbitals accessed in the collision process. In order to further our knowledge about the collision dynamics, potassium cation (K+) energy loss spectrum has been obtained and within this context, we also discuss the role of the accessible electronic states. A vertical electron affinity of (−5.69 ± 0.20) eV was obtained and may be assigned to a π3*(b1) state that leads to CN− formation., MM, SK, and FdS acknowledge the Portuguese National Funding Agency FCT-MCTES through PD/BD/106038/2015, PD/BD/142831/2018, and researcher position IF-FCT IF/00380/2014, respectively, and together with PL-V the Research Grants UID/FIS/00068/2019 (CEFITEC), PTDC/FISAQM/31215/2017, and PTDC/FIS-AQM/31281/2017. This work was also supported by Radiation Biology and Biophysics Doctoral Training Programme (RaBBiT, PD/00193/2012); UID/Multi/04378/2013 (UCIBIO). GG and AA acknowledge partial financial support from the Spanish Ministerio de Economia, Industria y Competitividad, Project No. FIS2016- 80440 and Project CTQ2013-41307-P. M-CB-M acknowledges support from the computational resources from the CCIN2P3 in Villeurbanne and CCRT/CINES/IDRIS by GENCI (Grand Equipement National de Calcul Intensif) under the allocation A0030807662.

Micromotor-mediated synthesis of thread-like hydrogel microstructures in an aqueous environment is presented. The study utilizes a catalytic micromotor assembly (owing to the presence of a Pt layer), with an on-board chemical reservoir (i.e., polymerization mixture), toward thread-like radical-polymerization via autonomously propelled bots (i.e., TRAP bots). Synergistic coupling of catalytically active Pt layer, together with radical initiators (H2 O2 and FeCl3 (III)), and PEGDA monomers preloaded into the TRAP bot, results in the polymerization of monomeric units into elongated thread-like hydrogel polymers coupled with self-propulsion. Interestingly, polymer generation via TRAP bots can also be triggered in the absence of hydrogen peroxide for cellular/biomedical application. The resulting polymeric hydrogel microstructures are able to entrap living cells (NIH 3T3 fibroblast cells), and are easily separable via a centrifugation or magnetic separation (owing to the presence of a Ni layer). The cellular biocompatibility of TRAP bots is established via a LIVE/DEAD assay and MTS cell proliferation assay (7 days observation). This is the first study demonstrating real-time in situ hydrogel polymerization via an artificial microswimmer, capable of enmeshing biotic/abiotic microobjects in its reaction environment, and lays a strong foundation for advanced applications in cell/tissue engineering, drug delivery, and cleaner technologies.

Mapping of structures, such as discontinuities, in an exposed rock mass is fundamental for slope stability analysis. This study investigates mobile laser scanning technology to identify structural discontinuity in a complex environment where the exposed rock face is partially covered with vegetation. The conventional terrestrial laser scanning and photogrammetry based approaches for structure identification rely solely on coplanarity criteria or point normal vectors and often miss several prominent discontinuity planes in a complex environment with inherent noise. To enhance structural mapping in such environments, this study tests a mobile scanner which has multi-view data collection to reduce blind spots. A new automated and robust algorithm termed clustering on local point descriptors (CLPD) is developed for more accurate discontinuity identification. The algorithm involves a rigorous pre-processing step to remove erroneous and irrelevant points followed by computation of local point descriptors. Five descriptors (i.e. eigenvalue descriptor (EVD), radial surface descriptor (RSD), fast point feature histogram (FPFH), normal and curvature) were generated for each point to capture spatial distribution, geometrical relationships and local surface variations in the point cloud. Finally, a K-Medoids clustering was performed on the computed descriptors using a histogram of normals to identify discontinuity planes. Results indicate that the proposed CLPD algorithm outperforms existing approaches in terms of accuracy in discontinuity orientation estimate (3.50° in dip angle and 4.32° in dip direction) for the study site. The stereonet comparison also validated that the poles distribution from CLPD is on par with the ground truth as well as results from commercially available software. The study presents a comparative evaluation of various approaches for kinematic feasibility of planar, wedge and sliding failures.