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The use of back-to-back built-up channel beams in cold-formed steel (CFS) structures is steadily rising. The growing demand for CFS sections as a cost-effective design solution has driven the development of these CFS built-up sections. Despite this, there has been limited research on the performance of mild steel (MS) based CFS at high temperatures, particularly regarding its flexural behavior. This study thoroughly explores the behavior of MS-based CFS beams with different spans under high temperatures, followed by cooling with air or water. It assesses the impact of thermal loading and evaluates the effectiveness of these cooling methods. Experimental findings are validated and analyzed in conjunction with Finite Element Modeling (FEM) using ABAQUS and the Direct Strength Method (DSM). The study also conducts a parametric analysis to determine how the varying span that affects flexural capacity of beam. Among beams heated to the same temperature, those cooled with water exhibit slightly lower load capacities than those cooled with air. The maximum load observed is 91.21 kN for the reference specimen, while the minimum load is 39.82 kN for the specimen heated for 90 min and cooled with water, resulting in a 78.45% difference between these values. Additionally, as heating duration increases, ductility of beam also increases. Various failure modes are observed based on different heating and cooling conditions across different beam spans. This study offers valuable insights into the performance of MS-based CFS beams under thermal stress and different cooling conditions, providing important data for structural design and safety in construction.

Due to infrastructural development activities, the need for the construction materials increases, because of which most of the naturally available natural resources are over exploited and the cost of construction materials are increased. Therefore, the present study focuses on the use of industrial by-products for the development of concrete and examines the physical, mechanical, durability and sustainable performances. Fly ash (FA) and ground granulated blast furnace slag (GGBS) were employed as binder medium and the industrial effluent sodium silicate waste was used to replace the conventional river sand in the geopolymer concrete (GPC). GGBS was employed as source material for the production of concrete to increase the polymerization reaction process and further, the developed concrete was cured in the ambient condition of temperature range 27 ± 2 °C, in the laboratory. The concentration of the sodium hydroxide (NaOH) in the present study was 12M, and the alkaline solution ratio was 1:1.5. During the production process of sodium silicate solution in the factory, the residue left at the bottom of the boiling hopper were dumped as waste in the open land. GPC gains its strength based on the alumina and silica in the source material and alkaline activator solution, therefore, this industrial waste residue was identified as potential alternative to conventional river sand. The concrete with and without effluent was subjected to two types of acid (Sulfuric acid (H2SO4) and Hydrochloric acid (HCl)) and further to examine the performance of concrete under marine condition, two types of salt solutions, namely, magnesium sulfate (MgSO4) and Sodium Chloride (NaCl) were used, the concentration of acids employed in the present study is 2% and the marine solution is 3.5%. Increase in the proportion of effluent from 0% to 100% decreases the slump value of the concrete. Contrastingly, increasing the proportion of effluent increases the strength of GPC after 28-d of room temperature curing. To examine the performance of the concrete under acidic and marine conditions, average of three concrete specimens were employed and the duration of exposure was considered in the present study starts from 28-d and continues till 360-d. After exposing to acidic environment, mass loss, strength loss and surface modification were examined; the loss in mass was found to be 1.5–3% and the strength loss was found to be 35%–45%. In the case of salt solution exposure, the loss in mass was seen to be 1–2% and whereas in the case of strength, the loss was found to be 30%–42%, respectively. Further, the sustainability aspects of the concrete with industrial effluents were examined in detail; focusing on economic value of the concrete, carbon emission and energy demand during the production of concrete.

This study examines the physical, mechanical, and durability characteristics of geopolymer concrete (GPC) when blended with sodium silicate waste (SSW). SSW was added in varying amounts from 0 % to 50 %. The concrete was exposed to sulfuric acid and nitric acid (both at 2 % concentration) over 360-d, with assessments every 28-d to observe long-term performance in acidic and marine environments. The concrete's workability decreased by 35 % when 50 % SSW was added, making it stiffer. Compressive strength increased by 18 % with 50 % SSW, indicating enhanced polymerization. After 360-d, mass loss was minimal (2 % with sulfuric acid, 2 % with nitric acid), while strength loss ranged between 35 % and 37 %. In marine environments (sodium chloride (NaCl) & magnesium sulfate (MgSO4), the observed mass loss after 28-d was about 1 %, and strength loss was slightly lower with 50 % SSW (38 %) compared to GPC without SSW (39 %). Using SSW, the cost efficiency improved by 21.71 % and energy efficiency improved by 18.56 % compared to concrete without SSW. The study concludes that SSW can be a reliable and sustainable alternative in GPC, offering enhanced performance and cost-efficiency.

The production of Ordinary Portland Cement (OPC) composites contributes significantly to carbon dioxide (CO2) emissions, necessitating a shift towards more environmentally friendly alternatives in the construction sector. This study explores the potential of incorporating Nano Bentonite (nBT) into Fly Ash (FA) and Ground Granulated Blast Furnace Slag (GGBFS) based Alkali Activated Nano Concrete (AANC) to improve both environmental impact and mechanical properties. Various concentrations of nBT (3%, 6%, 9%, 12%, and 15%) were added to the AANC mixtures, denoted as nBTx. The impact of nBT on fresh properties, mechanical strength, and microstructure of AANC was assessed through standard tests including setting time, slump value, ultrasonic pulse velocity (UPV), compressive strength (CS), splitting tensile strength (STS), flexural strength (FS), modulus of elasticity (MOE), and density. Results show that the addition of nBT decreased setting times, though reduced workability, and facilitated the formation of a compact microstructure, leading to improved mechanical properties. Notably, a 6% nBT concentration demonstrated a significant enhancement in CS, STS, FS, and MOE. Microstructural examinations confirmed the efficient distribution of nBT within the AANC matrix, contributing to a solid microstructure with reduced micro cracks and voids. However, challenges such as non-uniform dispersion and potential agglomeration were noted at higher nBT concentrations. Overall, the integration of nBT into AANC presents a promising pathway towards environmentally sustainable construction practices, offering potential energy conservation benefits and enhanced sustainability in the construction industry.

This experimental study delves into the impact of Multi-Walled Carbon Nanotubes (MWCNTs) on Geopolymer Concrete (GPC), investigating their effect on compressive strength and load deflection behaviour. MWCNT concentrations ranging from 0.02% to 0.16% were employed to examine their influence on the structural performance of 1500 mm (L) x 150 mm (B) x 150 mm (D) concrete beams. The findings derived from this investigation yielded several significant conclusions. The outcome of research identified the optimum MWCNT dosage for enhancing compressive strength at 0.12%, resulting in a substantial strength of 29.78 MPa. However, surpassing this concentration led to a decline in concrete strength. Notably, a remarkable 26.62% increase in compressive strength was observed with the 0.12% MWCNT concentration when compared to reference specimens. In analysing structural performance, it was observed that the energy absorption capacity (EAC) exhibited consistent behavior up to 0.6% addition of MWCNT. At 0.12% MWCNT inclusion, the EAC of the GPC reached its peak value at 6116 kN.mm. Stiffness maintenance mirrored the EAC trends up to 0.1% MWCNT, beyond which a decrease in stiffness was noted with higher MWCNT concentrations. Furthermore, the Density Index (DI) of GPC beams was sustained up to 0.1% MWCNT, after which DI began to increase. The Flexural Toughness Factor (FTF) of GPC beams retained its value up to 0.06%. However, addition of MWCNT with a higher concentration of 0.12% MWCNT, declined its flexural strength. Additionally, Scanning Electron Microscopy (SEM) images revealed a denser internal structure at the optimal dosage of 0.12% MWCNT. Subsequent additions of MWCNT led to increased agglomeration, potentially hampering effective interaction between the binder, MWCNT, and activator within the concrete matrix. These findings contribute to obtain the optimised MWCNT concentrations for superior performance in Geopolymer Concrete applications.

Corrosion in reinforced concrete (RC) structures is a typical occurrence, particularly in coastal locations. Corrosion occurs when steel reinforcement within concrete is exposed to environmental variables such as moisture, oxygen, and chloride ions, resulting in a chemical reaction that deteriorates the steel and degrades the concrete structure's overall function. In order to create effective mitigation techniques, it is critical to evaluate the impact of corrosion on various types of concrete. Chloride ions, often present in marine environments penetrate the concrete cover and reach the steel reinforcement, through pores. The water-cement ratio is a critical factor in concrete mix design. Excess water in the mix can result in the formation of larger and interconnected pores, during the hydration process. Further, improper curing conditions, such as insufficient moisture during the initial stages of hydration, can cause incomplete hydration and the formation of pores. Therefore use of high dense and highly alkaline concrete such as geopolymer concrete (which does not require water curing), can be employed to reduce the impact of corrosion. In the present study an attempt was created to examine the rate of corrosion resistance in three different concrete types: conventional cement concrete (CC), self-compacting concrete (SCC), and geopolymer concrete (GPC). To induce corrosion in the RC (RC) beams, an accelerated corrosion test setup was employed. The main objective of the study is to examine and compare the corrosion resistance of the RC beams by altering the concrete type, which were then exposed to accelerated corrosion to replicate the consequences of long-term exposure to corrosive environments. From the experimental studies it was found that the CC specimens possess a loss (load carrying capacity) of 31.28%, the SCC and GPC specimens possess a loss of 30.08% and 24.95%, respectively. This shows that GPC has higher resistance to salt solution when compared to SCC and CC specimens. Further all the three specimens show similar ductility index (DI), which was found to be in the range between 2.3 and 2.38 with a marginal variation of ± 0.1. GPC shows a 27.41% reduction in carbon emission compared to CC. On the other hand, SCC demonstrates a 12.30% reduction in carbon emission compared to CC. The investigation revealed that the total energy demand for producing 1 m3 of conventional concrete was measured to be 1.88 gigajoules (GJ/m3). On the other hand, the energy demand for the same volume of self-compacting concrete was slightly lower, specifically 1.78 GJ/m3.

Fires occurring within buildings present a grave concern, as they entail substantial risks to human lives, property, and the environment. Implementing appropriate fire safety measures becomes imperative to mitigate the occurrence of fires and ensure efficient response in the event of an incident. The primary aim of the study is to examine the performance of various coatings on the residual strengths of the reinforced normal strength self-compacting geopolymer concrete (NSGC) and high strength self-compacting geopolymer concrete (HSGC) columns subjected to standard temperature exposure in accordance with ISO 834 guidelines. The design compressive strength of the concretes was 36.12, 57.06 and 52.8 MPa. Two types of coating were employed in the present investigation namely ceramic wool wrapping and high alumina cement. A computerized electric furnace is used to heat the column specimens. Amongst the forty-two columns developed, six specimens tested without temperature exposure and protective coating as a reference specimen. Twelve specimens were heated as per ISO fire curve and tested to assess the residual axial strength performance and twenty-four specimens were coated with protective layers, then heated and tested to assess the post fire performance. It is exemplified that the composite protective coating offers effective resistance to concrete, gaining optimum axial strength performance. The findings show that these fire protecting composites have a high potential for utilizing as new strengthening techniques for reinforced concrete (RC) columns.

The study assesses the mechanical efficiency, long-lasting characteristics, microstructure, and sustainability of sustainable concrete (SC) samples through several optimization methods, emphasizing the significance of the 3Rs (recycle, reuse, reduce) approach in the construction sector. The study uses advanced techniques like the Taguchi method, grey relational analysis (GRA), analysis of variance (ANOVA), and signal-noise ratio (SNR) to optimize parameters affecting the performance of SC. In this study, the properties of SC are assessed by considering various parameters. These parameters include the use of 10 %, 20 %, and 30 % of ground granulated blast furnace slag (GGBFS) as a replacement for fly ash (FA). Additionally, six different binder contents ranging from 300 kg/m3 to 600 kg/m3 are examined. The study also investigates three different molarities of sodium hydroxide (NaOH) (8 M, 12 M, and 16 M), three different ratios of alkaline activators (AA) (1.5, 2.0, and 2.5), three different AA to-binder ratios (0.30, 0.35, and 0.40), and curing temperature (CT) of 30 °C, 60 °C, and 90 °C. The study includes fresh properties such as fresh density (FD) and slump, mechanical properties such as tensile strength (TS), flexural strength (FS), modulus of elasticity (MOE), and compressive strength (CS), and durability studies such as dry density (DD), impact strength, water absorption (WA), and sorptivity. The blended proportions were obtained using the Taguchi method. The study shows that GGBFS accelerates geopolymerization in FA-based concrete, reducing setting time and early-age CS. FA is crucial for setting time, workability, and CS enhancement. GGBFS increases the densities of fresh and hardened concrete, with a highly correlated increase, allowing accurate hardened density prediction with a coefficient of 0.9057. The CS of the cube SC surpassed 40 MPa, irrespective of variables such as the AA ratio, CT, and NaOH molarity. The trail mix with a binder concentration of 600 kg/m3, 30 % GGBFS content, 12 M NaOH molarity, 1.5 AA ratio, 0.35 AA to binder ratio, and 90 °C CT exhibited the greatest strength. Mixtures containing 10 % GGBFS can attain a CS above 30 MPa after 28 days, making them suitable for structural purposes. The T18 mix exhibited a compact Calcium (alumino) silicate hydrate (C-A-S-H) and N-A-S-H gel, whereas the T3 mix displayed a varied and permeable structure. The study used GRA, ANOVA, and SNR methods to analyze properties varying by six variables, finding GGBFS content as the most influencing parameter. The study found that the SC had a lower sustainability score than the OPC mix, but had better energy efficiency.

Skin cancer is a serious health issue that affects millions of people worldwide. One in every three cancers is a skin cancer and, most people fail to identify and get a diagnosis which is why early detection is essential for effective treatment and improving patient outcomes. In recent years, computer vision and machine learning have become important tools for the automatic detection of skin cancer. One of the commonly used machine learning algorithms for this task is Support Vector Machines (SVMs). SVMs are a type of supervised learning algorithm that is used for classification tasks. In skin cancer detection, the SVM classifier is trained on a dataset of dermatoscopic images of skin lesions. The first step in the process is feature extraction, where relevant information is extracted from the images to serve as input to the SVM classifier. This information can include color, texture, and shape features, among others. The training and testing of the SVM classifier is then performed using a portion of the dataset, with the remainder being used to evaluate its performance. During the testing phase, the SVM classifier is used to predict the class label of each image, which can be malignant or benign. The accuracy of the classifier is evaluated by comparing its predictions to the actual class labels of the images in the evaluation dataset. The results of using SVMs in skin cancer detection have been promising, with high accuracy rates being achieved. This highlights the potential of SVMs as a useful tool for skin cancer screening and early detection. In conclusion, the use of SVMs in skin cancer detection provides a fast, automatic, and reliable method for detecting skin cancer, which can help to improve patient outcomes. Currently it is really very important to watch and analyse the cancer disease automatically at intervals the first stages. Irregular streaks square measure one in every of the foremost very important features (included in most of dermoscopy algorithms) that show high association with carcinoma and basal cell malignant growth malady. The diagnostic test technique for the detection is most painful and harmful so we have a tendency to tend to square measure going for the machine-driven detection. Here we have a tendency to tend to square measure practice the GLCM choices for the detection the choices of skin lesions square measure extracted normalized symmetrical grey Level Co-occurrence Matrices GLCM. GLCM based texture choices square measure extracted from each of the four classes and given as input to the Multi-Class Support vector machine that's utilized for classification purpose.

Radiation Shielding Concrete plays a critical role in safeguarding against ionizing radiation, in nuclear power plants, medical facilities, and other radiation-sensitive environments. This review paper presents a comprehensive examination of radiation shielding concrete development, highlighting a novel approach that incorporates a diverse range of natural and industrial materials. Traditional radiation shielding concrete formulations rely heavily on virgin materials, contributing to environmental degradation and resource depletion. In contrast, this paper explores the innovative use of natural materials, industrial by-products, and waste materials, emphasizing the environmental sustainability and resource efficiency of such approaches. By harnessing these alternative materials, the paper outlines how radiation shielding concrete production can significantly reduce its ecological footprint while maintaining or even enhancing its radiation shielding capabilities. The paper delves into the functional aspects, composition variations, and performance characteristics of radiation shielding concrete, providing a holistic perspective on the diverse materials employed. Additionally, it thoroughly examines the factors influencing the effectiveness of radiation shielding concrete in nuclear power plants. Furthermore, this review discusses recent developments and advancements in radiation shielding concrete, offering insights into the cutting-edge research and innovations that are shaping the future of radiation shielding. The integration of natural and industrial materials presents promising avenues for enhancing the versatility, cost-effectiveness, and sustainability of radiation shielding concrete.

Extensive infrastructure development has led to the overexploitation of traditional virgin materials. To preserve the ecosystem, it's crucial to find alternatives. This study explores the viability of using turmeric bulb (TB) as a substitute for virgin coarse aggregate in geopolymer concrete (GPC). With 36 trial mixes varying in activator concentration and curing methods, the aim is to assess TB as a filler material replacement. Experimental trials revealed that replacing up to 20% of the coarse aggregate with TB maintained 28-day compressive strength at 35–38 MPa under ambient curing. However, with oven curing, strength was sustained only up to a 30% TB replacement, beyond which it declined. The UPV value for concrete with 50% TB was 3.79–3.9 km/s. Increasing the activator concentration from 8 M to 16 M significantly enhanced GPC strength, ranging between 24 and 36 MPa. GPC blended with TB showed a higher rate of water absorption, ranging from 24% to 26% for 50% replacement of conventional coarse aggregate. Sustainability analysis revealed that lower activator concentrations (e.g., 8 M) offered a more sustainable alternative to traditional cement concrete. In conclusion, this study underscores the potential of replacing coarse aggregate in GPC, promoting eco-friendly concrete production through sustainable practices and optimized activator concentration.

Ordinary Portland Cement (OPC) composites significantly affect the atmosphere by emitting Carbon dioxide (CO2) during its production process. The addition of Nano Materials (NM) for the construction could change the matrix configuration at the nano level. Compared to other NMs, converting industrial by-products and locally available materials into nano size can enhance the characteristics of the binder composites. This research work focuses on the effects of Nano Fly ash (nFA), on the fresh, mechanical, microstructural, and thermal resistance properties of Fly Ash (FA) and Ground Granulated Blast Furnace Slag (GGBFS) based Alkaline Activator Nano Concrete (AANC). The impact of adding nFA in various concentrations of 3 %, 6 %, 9 %, 12 %, and 15 % on the properties of AANC was studied. By adding nFA in an optimal proportion, the degree of geo-polymerization is improved which is found by Field Emission Scanning Electron Microscopy (FESEM), X-ray diffraction (XRD), Thermogravimetric analysis (TGA), Energy Dispersive X-Ray Analysis (EDAX) and Fourier Transform Infrared (FTIR). Results indicate that the addition of nFA significantly increased polymerization, reducing initial and final setting times by 13.3 %–52.5 % and 5.3 %–28.8 %, respectively. Moreover, nFA promoted the formation of polymer gel, leading to a denser microstructure with fewer cracks and refined pores, resulting in a substantial increase in mechanical strength, particularly with 9% nFA, achieving an optimal CS of 56.14 MPa after 28 days which is 37.97 % improvement compared to the mix without nFA. However, when nFA was added, beyond 9 %, the performances declined due to its high surface area resulting in a non-uniform dispersion that promoted agglomeration. This dispersion enhances the formation of C-A-S-H and C–S–H gels. The addition of nFA in AANC can be an environmentally friendly solution by reducing CO2 emissions, energy consumption, cost reduction and increased sustainability.

Geopolymer concrete (GPC) is an emerging green substitute for conventional cement-based concrete. Due to the eco-friendly benefits of GPC, it possesses superior strength properties. Self-compacting concrete (SCC) is a special concrete, it has the tendency to pass and fill congested areas without the help of vibrators. As the Self-compacting based Geopolymer concrete (SCGC) is a sustainable construction material, the knowledge about the thermal performance of SCGC is vital. Therefore, the current work examined the behavior of binary blended SCGC under room temperature and elevated temperatures of 821 °C, 925 °C, 986 °C, and 1029 °C. The investigation's main objectives are to examine the bond performance and microstructure of binary blended SCGC composites subjected to temperature exposure. Three types of mixes are considered in the investigation, namely FA (100% Fly Ash (FA)), F-G (50% Fly Ash (FA) and 50% Ground Granulated Blast Furnace Slag (GGBS)), and F-M (50% Fly Ash (FA) and 50% Metakaolin (MK)). The workability tests, such as the Flow test, T500 test, V-funnel test, and J-ring tests, were carried out in line with EFNARC guidelines to examine the rheological properties of SCGC. The SCGC composites were subjected to temperature exposure following ISO 834 standard fire curve. The Pull-Out (PO) test was carried out to investigate the Bond stress (BS) of the heated and unheated SCGC composites. The Bond stress of the SCGC composites decreases with an increase in temperature exposure. Test results show that the F-G mix possesses higher BS for unheated specimens, followed by F-M and FA mix. When exposed to elevated temperature, the SCGC composite mix F-G and F-M exhibit higher strength loss (%) than the FA mix. A relationship has been established between the compressive and bond stress of SCGC.

Fiber-reinforced geopolymer concrete has been attracting attention and interest worldwide due to its sustainable properties. However, few studies have reported the pull-out behaviour of fiber-reinforced geopolymer concrete (GPC) at elevated temperatures. In order to bridge this knowledge gap, a series of detailed investigations aimed to investigate the effect of elevated temperatures on the mechanical and microstructure properties of fiber-reinforced geopolymer concrete. In the present investigation, crimped steel fibers (SF), polypropylene fibers (PF), basalt (BF), and hybrid fibers such as SF:PF and PF:BF is employed to develop the GPC. Alkaline activators such as sodium hydroxide (NaOH) of 8 M and 10 M and Na2SiO3/NaOH ratios of 2.5 are used in the production of M35 and M40 grade GPC. Compressive strength, weight loss, crack pattern, bond strength, and microstructure of fiber-reinforced GPC specimens have been evaluated, after exposing to higher temperature following ISO 834 standard fire curve. Results from the conducted tests show that adding various types of fibers improves the compressive strength and bond strength of the GPC specimens. More specifically, amongst all tested specimens, the exposed GPC-BF shows lesser weight loss and higher residual compressive strength with fewer cracks on the surface of the specimens. on the other hand, GPC with SF shows higher residual bond strength than other fiber-reinforced GPC specimens. Microstructure analysis (SEM/EDAX) confirms the extent of damage and contribution of fiber in the temperature-exposed GPC. A statistical relationship and correlation has been obtained between compressive and bond strength.

This paper presents an investigation on the effect of protective coatings of high-strength self-compacting geopolymer concrete (HSGC) when subjected to standard fire conditions. The study involved the use of two types of protective coatings, namely ceramic-wool plaster and alumina-bauxite cement plaster, to insulate 42 beams. The findings of this study reveal that employing geopolymer concrete combined with ceramic-wool and alumina-bauxite protective coatings constitutes a significant advancement in fire-resistant construction materials. Specifically, the application of protective coatings to geopolymer concrete beams introduces an additional layer of insulation and fire resistance, resulting in a reduced rate of temperature rise and prevention of spalling and cracking. Both wool-plaster and powder-plaster coating materials exhibit higher heat resistance properties, displaying 2–4 times greater resistance than specimens without protective coatings. The wool-plaster protective coating significantly enhances the residual load-carrying capacity, achieving 97.8% for fly ash (FA)-blended specimens at 821 °C, demonstrating 96.6% and 96.26% for FG (fly ash-ground granulated blast furnace slag) and FM (fly ash-metakaolin) specimens, respectively. Similarly, powder-plaster coated FA and FG specimens exhibit 87.5% and 89.4% residual load-carrying capacity at 821 °C, while FM-blended mix specimens exhibit 89.6%. In specimens subjected to 1029 °C, the residual load-carrying capacity for wool-plaster coated FA, FG, and FM-based specimens was found to be 75.8%, 72.37%, and 69.62%, respectively. Powder-plaster coated specimens exhibited a similar trend with a residual load-carrying capacity of 67.74%, 64.9%, and 66.82% for FA, FG, and FM blends, respectively. Notably, wool-plaster coated specimens proved superior performance compared to powder-plaster coated ones, retaining 75–85% of their strength after 60 min of heating exposure. Conversely, powder-plaster coated specimens retained the same percentage of strength after 30 min of heating exposure. However, an increase in heating intensity and duration led to a decrease in the strength of the concrete mix.

The appearance of fruits is crucial in their quality grading and consumer choices. Colour, texture, size, and shape determine fruit quality. Existing computer vision systems have been implemented for external quality control, relying on observations for fruit grading and classification. Banana quality detection systems, which employ advanced algorithms and sensors to evaluate the ripeness and general quality of bananas throughout their life cycle, are an innovative application of smart farming technology. In this proposed system, Knowledge Embedded-Graph Convolutional Neural Networks (KEGCNNs) are employed to classify and grade banana fruit. The approach aims to detect banana fruit quality by converting banana images into a knowledge graph, applying knowledge embedding to transform them into a continuous vector space, and using Graph Convolution Neural Networks (GCNNs) to analyze the graph structure and make accurate detections. KEGCNNs are especially useful for detecting the quality of banana fruits because they provide a form for capturing the contextual interactions between distinct nodes. KEGCNNs can learn from the data within the graph in an unsupervised manner, allowing them to use the knowledge inherent in the graph structure. KEGCNNs enable more accurate and efficient diagnosis of banana quality as they can discover patterns in data that conventional machine learning algorithms cannot. The suggested technique demonstrates an impressive performance score, indicating its suitability for detecting the quality or grade of banana fruit.

The development of sustainable infrastructure is a serious issue faced by modern society. Portland cement is one of the common ingredients in concrete, which influences construction activities. The major issue with the employment of cement in civil-based works is that it is responsible for carbon dioxide emission (CO2-e), the primary greenhouse gas responsible for global warming. Alternative to cement-based concrete, geopolymer concrete (GPC) employs zero cement for concrete production, leading to a reduction in CO2-e. In the case of mass concreting, interface/joints are developed, which are found to be the possible failure spots of brittle fracture. Concrete with different grades (strength) may interface, or other building materials, such as reinforcing materials. The interfacial bond strength has to be examined to ensure the homogeneity of the composite structures. The employment of shear ties at the interface ensures homogeneous behaviour. Moreover, a higher number of shear ties in the shear zone increases the cost of production. The interfacial shear strength (ISS) parameters will be miserably damaged in the concrete structures subjected to fire accidents, which might depend on the intensity of temperature exposure and its duration. The current study investigates the ISS of the High Strength Self-compacting geopolymer concrete (HSGC) in the interface of push-off samples. SCGC was made using binary blended composites, which comprised Fly Ash (FA), Metakaolin (MK), and Ground Granulated Blast Furnace Slag (GGBFS) as precursor materials. The work highlights the need to comprehend the reduction in shear strength of SCGC subjected to high temperatures. The fresh properties of the SCGC composites strictly adhered to the EFNARC guidelines. The SCGC composites, after their curing period, were exposed to 821 ℃, 925 ℃, 986 ℃, and 1029 ℃ following ISO 834 guidelines. Residual mechanical properties were examined after being cooled to room temperature.

Cold-formed steel (CFS) sections are light gauge materials widely used to construct industrial structures. CFS construction is gaining more interest among researchers, construction industries, and structural engineers due to its lightweight and cost-effective design. Fire safety in the building is a significant factor to be considered in the design and construction practices. However, limited studies are reported on experimental and finite element modelling (FEM) of back-to-back built-up channel sections under flexure with unrestrained conditions. Nine back-to-back built-up CFS sections were considered for the experiment. CFS test specimens were exposed to elevated temperatures following the ISO 834 standard fire curve for durations of 30 min (821 ℃), 60 min (925 ℃), 90 min (986 ℃), and 120 min (1029 ℃). After the temperature exposure, air- and water-cooling methods were adopted to cool the CFS specimens. The influence of temperature exposure and cooling affects CFS sections' residual load-carrying capacity and failure behaviour. A detailed physical observation was made after cooling conditions to observe the failure behaviour of CFS specimens. Experiments were performed to evaluate the influence of elevated temperature exposure on the ultimate flexural capacity, moment-deformation behaviour, load-strain behaviour and stiffness of CFS. The moment of resistance results obtained from FEM and the Direct Strength Method (DSM) were validated with experimental results. The experimental results showed that, while increasing the temperature exposure and heating duration, the CFS's load-carrying capacity decreases drastically. In the case of cooling conditions, air-cooled specimens exhibited a higher residual strength capacity, about 10–15%, compared to the water-cooled specimens. A good correlation was noted between the experiment and FEM results in failure modes.

Cement replacement materials have been the subject of increasing levels of research and development in recent years. These products are employed for many reasons, including to modify the properties of concrete, although the most urgent need for their use currently is to produce more sustainable concrete and reduce waste. Recently, nanomaterials such as nano-fly ash and nano-metakaolin have been studied as cement replacement materials as they tend to fill the pores present in the matrix, thereby increasing the density of the concrete resulting in an enhanced hydration process and greater mechanical performance. This paper is concerned with the post-fire mechanical and durability behaviour of concrete containing nanomaterials as a cement replacement material, for which there is no information available currently. The key information and results from an experimental investigation are presented and discussed. The experimental programme studied both nano-fly ash and nano-metakaolin with a cement replacement ratio of between 5% and 25%. The specimens were subjected to a standard fire and then cooled either slowly, in air, or quickly in water. Based on the test data, it is concluded that the presence of either of these nanomaterials in concrete reduces the pore volume and increases the pozzolanic activities in the mix, leading to enhanced mechanical and durability behaviour compared with traditional concrete. The optimization trials indicate that the best replacement ratios are 20% for the nano-fly ash and 15% for the nano-metakaolin. Overall, following elevated temperature exposure, the concretes containing nano-fly ash performed better than the concretes with nano-metakaolin but both out-performed traditional cement-based concrete.

Geopolymer Concrete (GPC) is a unique and sustainable building material that has the potential to be transformed into a self-compacted lightweight composite for industrial applications. This paper investigates the sustainability of self-compactable lightweight geopolymer concrete (SCLGC) made from Expanded Clay Aggregate (ECA) to further explore this front. In this study, the physical properties of SCLGC, such as slump flow test, T500 test, V-funnel, and J-ring tests, are examined. Furthermore, the density, Ultrasonic Pulse Velocity (UPV), compressive strength, splitting tensile strength, and impact resistance are also tested to evaluate the mechanical properties of SCLGC mix with various concentrations of Sodium Hydroxide (SH) cured under different curing regimes. The aforenoted properties are examined following the American, Indian and European guidelines. In addition, microstructural analysis is conducted to assess the compactness and internal structure of SCLGC blends with varying SH concentrations cured under different curing regimes. Finally, the sustainability aspects of GPC and SCLGC mixes are analyzed through the Life Cycle Assessment (LCA) and Environmental Impact Assessment (EIA) to evaluate the energy requirement and CO2 emission and cost. The Sustainability analysis was performed to evaluate the energy requirement and CO2 emission of SCLGC in the production of 1 m3 concrete based on the previous literatures. The significance of the proposed research work emphasizes the utilization of ECA as an aggregate material for the development of SCLGC. The cost, carbon and energy efficiency of the SCLGC's mixes were estimated. Mix with ECA requires higher energy demand and emits high CO2 in the open atmosphere. Based on the present analysis it can be concluded that an increase in the concentration of activator solution increases the energy demand and emits more amount of CO2. The inference from the present study reveals ECA can be employed for the production of SCLGC with the replacement percentage not exceeding 50%.

Nanomaterials (NMs) are being used to enhance the properties of construction materials. This review focuses on the use of NMs to improve the characteristics of fresh and hardened Geopolymer Composites (GC). Over 335 research publications are reviewed to detail the benefits and drawbacks of the integration of NMs in GC. More specifically, this review outlines the effects of numerous NMs such as Nano Silica (NS), Nano Alumina (NA), Nano Titanium dioxide (NT), Carbon Nano Tubes (CNT), Multiwall Carbon Nano Tubes (MCNT), Nano Calcium Carbonate (NCC), Nano Zinc oxide (NZ), Graphene Oxide (GO), Nano Metakaolin (NMK), Nano Fly Ash (NFA), Nano Glass Powder (NGP) and Nano-clay(NC) on Geo-polymer Paste (GPP), Geo-polymer Mortar (GPM) and Geo-polymer Concrete (GPC). The presence of NMs was found to enhance the geo-polymerization reaction and result in a denser matrix. The presence of NMs also enhances the durability of GC by preventing micro-pores interconnectivity. In hindsight, our review indicates that the addition of NMs is directly tied to producing high-performance GC, which the construction industry can effectively readily adopt. Additional insights, challenges, and future research directions are identified and discussed toward the end of this review.

In emerging economies, huge stocks of industrial wastes are dumped in open landfills. Such wastes serve as a source for environmental pollution. Some of these materials such as Fly Ash (FA), Ground Granulated Blast Furnace Slag (GGBFS), Rice Husk Ash (RHA), and Palm Oil Fuel Shell Ash (POFA) can be used as binder materials to produce concrete mix. Aim of the study is to effectively utilize the Municipal Solid Waste (Sodium Silicate Waste (SSW)) powder as a partial replacement for FA in the development of Geopolymer Concrete (GPC). GPC requires heat curing for the attainment of early age strength. The development of GPC under heat curing conditions is a hard process in practice. To overcome such circumstances, an attempt was made to develop the GPC under ambient curing conditions with the aid of SSW. The influence of SSW on strength gain and microstructural characteristics of GPC is investigated. Mechanical properties of GPC such as compressive strength, tensile strength, and flexural strength are reported and discussed. This study focuses on the assessment of mechanical and microstructure characterization of eco-efficient GPC developed with SSW. The required optimum quantity of binder, alkali activator, alkaline liquid to binder ratio and aggregates was determined by appropriate trials. Following the properties of SSW, it is realistic to substitute up to 50% of SSW as the resulting binder mix falls within the requirements of the analyzed mix. Increase in the percentage of SSW decreases the fresh properties of GPC, such as setting time and workability; mix with 50% SSW exhibited the lowest initial and final setting time i.e., 77% and 81% than the control mix. Contrastingly, inclusion of SSW content enhances the mechanical properties of the mix. 12SSW50 mix produces the maximum compressive, tensile and flexural strength of 40.16 MPa, 2.8 MPa, and 4.18 MPa, respectively. Mix with 8 M concentration comprising 50% SSW possess higher cost efficiency than the mix with higher alkaline content. The main significance of this research work is, SSW can be used as a precursor material as an alternative for cementitious binder with better efficiency in terms of strength, microstructure, and sustainability. Therefore, GPC produced with SSW is an eco-friendly and sustainable building material. Effective use of waste materials such as fly ash and SSW for the development of GPC is another major research focus in the proposed investigation.

Fire accidents are common and one among the serious hazards faced by civil infrastructures; therefore, appropriate measures have to be taken while designing the buildings and structures to ensure the safety of the residents. Reducing the damage caused by fire and the collapse of structural elements are the primary significance in designing concrete structures. An experimental study was conducted to examine the mechanical properties of temperature exposed concrete specimens following ISO 834 standard fire curve. Present investigation examines the performance of Geopolymer concrete (GPC) after exposed to temperature exposure. Two types of concrete namely, low and high strength GPC were cured under two curing regimes viz, room temperature curing and oven curing was adopted in this study. The GPC specimens were heated to 821 °C, 925 °C, 986 °C and 1029 °C, following the rate of heating was in accordance with ISO 834. Influence of elevated temperature on GPC specimens were examined by visual inspection, weight loss, strength loss and micro-level studies including Scanning Electron Microscope (SEM). Results from the study reveals that, the strength of high strength concrete was more prone to temperature exposure. Room temperature cured GPC specimens possessed higher residual strength than oven cured specimens for all the heating durations (marginal variation less than 5%). Crushing Index (CI) of 8.1% was regarded as optimal value for coarse aggregates (CA) to sustain its strength at a temperature of 821 °C. The phase change and dehydration of geopolymeric gel were observed in SEM analysis, and strength loss of CA are considered as the influencing parameters for degradation of concrete at higher temperature exposure. High strength concrete is more prone to strength loss than low strength concretes.

This paper presents an experimental and numerical analysis considering the effect of standard fire conditions on the post-fire strength of hot rolled hollow steel sections, where the influence of passive protection, cooling conditions and micro structural changes were also analysed with precision. Square, rectangular and circular shaped specimens were considered for the investigation. Cementitious perlite coating was used to improve the fire resistance of sections exposed to elevated temperature following the ISO 834 standard fire curve. Investigations were performed to evaluate the influence of fire conditions on the axial load capacity, deformation, stress-strain behaviour, yield stress, ultimate stress, and elastic modulus of sections. Finite Element Models (FEM) were developed and validated with experimental results. A detailed micro structural analysis was done with keen observation to assess the physical characteristics by scanning electron microscope (SEM) and image analysis. As expected, passively protected specimens show significantly higher post-fire resistance. In the case of water cooling, the post-fire capacity of sections decreased by approximately to 10–15%. Micro cracks were identified along with a greater proportion of pearlite in the micro structures of water cooled specimen

Concrete and reinforcement steel are essential building materials widely used in composite construction due to their advantages, such as strength, durability and ease of availability. Fire is one of the critical hazards that causes severe damage to the structure and leads to progressive collapse. Due to the intensity of fire exposure, the concrete and reinforcing steel significantly losses their inherent mechanical properties and service life. Minimizing the fire-induced damage and failure are the primary objectives in the design of concrete structures. Therefore, an extensive experimental attempt was undertaken to evaluate the pull out behaviour and also to improve the bond performance of concrete and reinforcement steel when exposed to elevated temperature. A cement based perlite coating was developed as a protective material to safeguard the concrete in the study. All the pull out bond test specimens were heated following the ISO 834 standard fire curve, and subsequently cooled either by air or water. Residual mechanical properties of steel rebar such as yield strength, ultimate strength, elastic modulus, shear and bending capacity were evaluated after the exposure to elevated temperature. Investigations were conducted on pull out specimens to evaluate the bond stress slip behaviour and bond strength of concrete. A detailed physical observation was made on the failed concrete specimens to examine the damage. A drastic reduction in bond strength of concrete and tensile strength of the rebar were observed while increasing the duration of heating. Also, it was observed that the coated specimens exhibited better performance by retaining the bond strength and yield strength of the rebar.

Interfacial shear stress transfer may occur in structural elements across concrete or between concrete and steel. The fundamental contributing parameters which improve the shear capacities are aggregate grading, compressive strength of concrete, type and area of the interfacial zone, and interfacial reinforcement pattern. During the event of a fire, these parameters are severely affected and mainly depend on the exposure level of the temperature and its duration. In the present investigation, the effect of elevated temperature on the interfacial Shear Transfer Capacity (STC) of Self-Compacting Concrete (SCC) was evaluated using shear (push-off) specimens. SCC was developed using Fly Ash (FA) and Ground Granulated Blast Furnace Slag (GGBFS) as Supplementary Cementitious Material (SCM). The study emphasises the proper understanding of degradation in shear strength of SCC exposed to elevated temperatures. Expanded Perlite Aggregate (EPA) is utilised as a partial replacement for fine aggregate. Also, a thermal protective coating is developed with Cement Perlite Plaster (CPP) for improving the performance of SCC. The European Federation of National Associations Representing for Concrete (EFNARC) guidelines were followed to ensure the workability of the developed SCC mix. Specimens were exposed to 30, 60, 90, and 120 min of heating durations following the International Organization for Standardization 834 (ISO 834) fire rating curve and tested to examine residual compressive strength, mass loss, STC after the natural air cooling process. The SCC specimens with EPA content have exhibited higher residual compressive strength and STC. All the protected SCC specimens coated with the CPP mixture contributed to retaining the original shear capacity by resisting the temperature. An empirical relationship was proposed to predict the residual STC of SCC after exposure to elevated temperature.

Background Chronic pancreatitis is a debilitating disease presenting with pain, diabetes and steatorrhoea. Surgery offers better long‐term pain relief than other interventions, but there is still uncertainty about the optimal surgical procedure and approach and a lack of long‐term follow‐up data in patients with chronic calcific pancreatitis selected for laparoscopic surgical treatment. Methods This was an observational cohort study of patients who underwent laparoscopic surgery for chronic calcific pancreatitis between January 2006 and April 2017, and had completed a minimum follow‐up of 1 year at a tertiary‐care teaching institute. Eligibility for the laparoscopic approach was main duct diameter greater than 7 mm, absence of extensive head calcification, size of head less than 3·5 cm, absence of local complications, and ASA grade I or II status. The primary outcome variable was a reduction in pain score by 1 year. Secondary outcomes were hospital stay, complications, pain score at 3 and 5 years, and the development or progression of exocrine and endocrine insufficiency. Results Some 57 patients were scheduled to undergo laparoscopic surgery for chronic pancreatitis: longitudinal pancreatojejunostomy (39), modified Frey's procedure (15) and pancreatoduodenectomy for suspicion of malignancy (3). The latter three patients were excluded from the analysis. Conversion to open surgery was needed in ten of the 57 patients (18 per cent). The mean(s.d.) age of the analysed cohort was 34·2(3·7) years and there was a predominance of men (34, 63 per cent). Adequate pain relief was achieved in 91, 89 and 88 per cent of patients at 1, 3 and 5 years of follow‐up respectively. Conclusion Laparoscopic surgical management of chronic calcific pancreatitis with longitudinal pancreatojejunostomy or modified Frey's procedure is feasible, safe and effective in selected patients for the relief of pain.

Genome-wide runs of homozygosity (ROH) are suitable for understanding population history, calculating genomic inbreeding, deciphering genetic architecture of complex traits and diseases as well as identifying genes linked with agro-economic traits. Autozygosity and ROH islands, genomic regions with elevated ROH frequencies, were characterized in 112 animals of seven Indian native cattle breeds (B. indicus) using BovineHD BeadChip. In total, 4138 ROH were detected. The average number of ROH per animal was maximum in draft breed, Kangayam (63.62 ± 22.71) and minimum in dairy breed, Sahiwal (24.62 ± 11.03). The mean ROH length was maximum in Vechur (6.97 Mb) and minimum in Hariana (4.04 Mb). Kangayam revealed the highest ROH based inbreeding (FROH>1Mb = 0.113 ± 0.059), whereas Hariana (FROH>1Mb = 0.042 ± 0.031) and Sahiwal (FROH>1Mb = 0.043 ± 0.048) showed the lowest. The high standard deviation observed in each breed highlights a considerable variability in autozygosity. Out of the total autozygous segments observed in each breed except Vechur, > 80% were of short length (< 8 Mb) and contributed almost 50% of the genome proportion under ROH. However, in Vechur cattle, long ROH contributed 75% of the genome proportion under ROH. ROH patterns revealed Hariana and Sahiwal breeds as less consanguineous, while recent inbreeding was apparent in Vechur. Maximum autozygosity observed in Kangayam is attributable to both recent and ancient inbreeding. The ROH islands were harbouring higher proportion of QTLs for production traits (20.68% vs. 14.64%; P≤ 0.05) but lower for reproductive traits (11.49% vs. 15.76%; P≤ 0.05) in dairy breeds compared to draft breed. In draft cattle, genes associated with resistant to diseases/higher immunity (LYZL1, SVIL, and GPX4) and stress tolerant (CCT4) were identified in ROH islands; while in dairy breeds, for milk production (PTGFR, CSN1S1, CSN2, CSN1S2, and CSN3). Significant difference in ROH islands among large and short statured breeds was observed at chromosome 3 and 5 involving genes like PTGFR and HMGA2 responsible for milk production and stature, respectively. PCA analysis on consensus ROH regions revealed distinct clustering of dairy, draft and short stature cattle breeds.

Abstract We use conformal symmetry to define an AdS3 proto-field ϕ as an exact linear combination of Virasoro descendants of a CFT2 primary operator O $$ \mathcal{O} $$. We find that both symmetry considerations and a gravitational Wilson line formalism lead to the same results. The operator ϕ has many desirable properties; in particular it has correlators that agree with gravitational perturbation theory when expanded at large c, and that automatically take the correct form in all vacuum AdS3 geometries, including BTZ black hole backgrounds. In the future it should be possible to use ϕ to probe bulk locality and black hole horizons at a non-perturbative level.

Buffaloes mostly suffer from delayed puberty, anestrus, sub–estrus, summer infertility, prolonged inter-calving interval and postpartum uterine disorders. Nesfatin-1 and Leptin are directly or indirectly related with body weight (BW), feed parameters and regulation of puberty. The objective of this study was to investigate the influence of Nesfatin-1 and Leptin in pubertal and non-pubertal Murrah buffalo heifers. The Murrah buffalo heifers (n=13) were randomly selected and divided into two groups; pubertal group (PG) and non-pubertal group (NG). Heifers with plasma progesterone (P4) level of ≥1 ng/mL were classified as PG. Blood samples were collected at fortnight intervals for analysis of plasma Nesfatin-1, Leptin, P4, glucose and non-esterified fatty acids. Body weight, dry matter intake and feed conversion efficiency were recorded at fortnight intervals. The mean (±SEM) plasma Nesfatin-1, Leptin, P4, BW and feed conversion efficiency (%) were significantly (P