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Air Circuit Breakers are used for circuit protection from the faulty current that might damage the subsystems of the circuits like motors, transformers, transmission systems, etc. The cost optimization of the component used in the mechanism unit of Air Circuit Breaker (ACB). This can be achieved by replacing the existing material AISI 9260 to equivalent proposed material AISI 4140. This material exhibits the better mechanical properties in all aspects, along with low process cost involved during manufacturing of the components. This paper presents comparative dealing with the properties like hardening & tempering, hardenability, weldability, stamping-ability, endurance limit, and modification factors of the existing material AISI 9260 to proposed material AISI 4140. The proposed steel AISI 4140 is suitable for ACB mechanism parts which exhibits the same reliability and better mechanical properties than presently used AISI 9260 steel. The proposed AISI 4140 steel reduces the cost of the component by elimination and replacing the partial or fully heat treatment cost and wire electric discharge machining (WEDM) cost respectively. Because the component manufactured with AISI 4140 steel shows the desired mechanical properties only in hot rolled conditions with additional localized hardening, wherever the rolling surface is present. The elimination and replacement of heat treatment and WEDM process cost involved in present AISI 9260 steel components, can be achieved by partial induction hardening and stamping process employed on proposed AISI4140 steel respectively. There are three conditions that is, when fully elimination of heat treatment saves 27% of the total process cost, when partial elimination of heat treatment cost saves 25.5% of the total process cost, and when replacing the WEDM to stamping saves 22% of the total component cost. The proposed material and process also maintain the same reliability for the rated 20,000 operations.

In today’s world, researchers are actively seeking the most suitable materials to meet the growing industrial demands. These materials need to possess specific characteristics such as lightweight nature, high strength, excellent mechanical properties, and environmental friendliness. Due to these requirements, relying solely on mono fiber composite materials is insufficient. Therefore, it has become necessary to incorporate different reinforcements into polymer matrices to achieve the desired mechanical properties. This study focuses on the fabrication of a novel hybrid composite using jute fibers, luffa fibers, palmyra leaf fibers, and AISI 303 (0.5 mm) wire mesh combined with epoxy resin. The fabrication process involved utilizing vacuum bagging techniques. To assess the mechanical properties of the hybrid composites, two wire mesh orientations (45° and 90°) and a total of 12 stacking sequences of jute/wire mesh/luffa/palmyra (J/W/L/P) were selected. The mechanical characterization of the hybrid composites included tensile, impact, flexural, and interlaminar strength tests. Furthermore, a dynamic mechanical analyzer (DMA-8000) was employed to investigate the elastic behavior, including storage modulus (E′), loss modulus (E″), and damping factor (tan δ). Additionally, the fracture surface's microstructure was examined using a scanning electron microscope (SEM). Among the various stacking sequences and fiber orientations, the 45° fiber orientation and the stacking sequences JWLP, JLWP, JWPL, JPWL, PWJL, and PJWL exhibited superior ultimate tensile strength. Notably, the PWJL stacking sequence displayed the highest average tensile strength (74.83 MPa), flexural strength (131.60 MPa), percentage elongation (1.35%), and interlaminar strength (1.47 kN). Moreover, dynamic mechanical analysis revealed that the hybrid composite sample with 90° wire mesh orientation exhibited a peak energy absorption of 0.820 at the transition region, specifically at a frequency of 0.5 Hz.

Predicting river discharge is essential for managing water resources, contributing to the economy, and minimising associated hydrologic risks. Despite the manifold importance of a sound understanding of river discharge, the rugged geography of Bhutan makes installing sophisticated water discharge measuring equipment challenging. Using an integrated flood analysis system - a non-structural method - is used to calculate the river discharge of the Punatshangchu River Basin. The two-tank configuration hydrologic model was applied through parameterisation, calibration, and validation and was forced using rainfall data. The maximum observed discharge was 1,532 m3/s and the minimum was 58 m3/s. The validated simulation model showed a maximum discharge of 1,522 m3/s and a minimum discharge of 138 m3/s, respectively. The simulated result overestimates the low flow and underestimates the high flow. A Nash-Sutcliffe efficiency of 0.7626 was achieved, indicating a satisfactory level of estimation. The study found that the IFAS model can predict river discharge in a data-scarce environment.

Natural fiber reinforced hybrid composite materials, with their enhanced characteristics, represent the future of our advanced material search. Natural fibers are the substitute for synthetics because their less manufacturing cost, bio-degradable, easy availability, durability, resistance to environmental degradation, etc., makes them popular nowadays. This paper presents how jute fibers are recycled from various jute waste sources. After recycling, jute fibers are used to fabricate the hybrid composites. Two forms of recycled jute sheets are used to fabricate the composites that is, woven sheets and nonwoven comingled (jute and polypropylene) sheets. The NaOH treatment was performed on recycled jute sheets with different concentrations (0%, 2%, 4%, 6%, and 8%). The hybrid composites are made using three distinct fiber-polypropylene weight fraction ratios (50/50, 40/60, and 30/70), as well as five different stacking sequences. Mechanical parameters such as tensile strength, elongation (%), flexural strength, impact strength, and water absorption were evaluated. Among the five fabricated combinations, it is found that the combination of (40/60), (JJJ), with 2% NaOH treated fibers composite gives the maximum tensile and flexural strength, and the combination of (30/70) (CCC) with 2% NaOH treated fiber composites exhibits the maximum Impact strength. The combination of (50/50), and (CCC) with 2% NaOH treated fiber composite gives the maximum Elongation %, and the combination of (50/50), (JJJ), and 0% NaOH treatment yields the maximum water absorption. A relationship between fabric loading, tensile modulus, and flexural modulus and other relationship between chemical treatment and water absorption% has been established for JJJ laminated sheet which shows almost best properties among them. These assessments make them most valuable for a variety of sectors, including car, aircraft, marine, and building construction.

In this research, main objective is to study the effect of heat transfer in a hybrid radiator (wavy and rectangular louvered) tube on the thermophysical properties of Aluminium oxide and copper oxide-based nanofluids. ANSYS Fluent has been used in the simulation and the SST-K-ε model is used since the flow condition is turbulent. The study presents a thorough comparison in physical properties of nanofluids with variable volume concentrations between 0.05 and 0.30 per cent. An increase in Nusselt number of 174% was established with CuO-based nanofluid compared to a 162% increase with Al2O3-based nanofluid. For a CuO-based nanofluid at a volume concentration of 3% and a mass flow rate of 6 l/min, convective heat transfer of 37021.41 W/mK is recorded, a 142% increase over the base fluid. Increasing mass flow and volume concentration reduces the friction factor. As volume concentration increases, heat transfer capacity increases and reaches a maximum of 8.93% higher than base fluid at a flow rate of 6 l/min.

Ordinary Portland cement (OPC) has a major contribution to the increment of greenhouse gases due to its increased demand as a construction material. To overcome this problem, researchers are being done to partially replace OPC by utilizing industrial by-products, which are cheap, and eco-friendly. Geopolymer is a new material having binding properties almost resembling the OPC. In this paper, fly ash (FA) and ground-granulated blast furnace slag (GGBFS) were used for geopolymer synthesis. A series of fly ash-based geopolymers was synthesized with varying NaOH (6 M, 8 M and 10 M) concentrations by blending GGBFS in ambient conditions. Compressive strength results show that more than 40% GGBFS in the blend of fly ash and GGBFS gives the desired strength, i.e., more than 35 MPa in an alkali activation at 27 °C, with high (6 M, 8 M, 10 M) molarity of the NaOH solution. In the isothermal conduction calorimetry test, the maximum heat of hydration was observed in the sample with 8 M NaOH and minimum with 6 M NaOH solution. In the durability test, the performance of the 1:1 blended FA-GGBFS system shows that the loss in strength is increased with the increase in alkali concentration. Samples with 6 M NaOH have shown a minimum loss, which was increased in the sample with 8 M and 10 M. Similar to the aforementioned, the loss of strength and loss in mass in the sample increased with the increase in alkali concentration. Also, characterization of prepared geopolymer samples (A66M, A610M, A56M and A510M) was done by XRD and FTIR spectroscopy.

Soil erosion is one of the most critical hazards adversely affecting both environment and economy. Assessment of the annual soil erosion rate provides information on soil erosion risk zones indicating the areas with high, severe and low risks. Modelling and prediction of soil erosion has a long history of more than seven decades. It becomes imperative to be familiar with the quantum of studies conducted and methods employed across the world to assess vulnerability of ecosystems to soil erosion to plan strategies for their conservation. There are several methods based on various factors like land use, soil quality, topography etc. available to assess the susceptibility of a region to soil loss. With time the gap in understanding of such models and their use around the world has increased. Numerous models for assessing soil erosion exist but there is a lack of knowledge on spatial distribution of the methods being used. Academic papers related to assessment of soil erosion vulnerability published during the past three decades (1991–2019) were reviewed. Total 160 studies were reviewed to understand advances in the methods used to assess soil erosion vulnerability worldwide, identification of the most popular methods and proportion of studies conducted in the fragile region of Himalayas. The results show that 18 different methods have mainly been used to assess soil erosion risk in different regions. These methods include statistical, physical, process based and empirical models. The use of few physical methods like ANSWERS and SHE has decreased with time while that of physical and process methods like RUSLE, SWAT, WEPP and PESERA has increased with time. The review highlighted that various models being used worldwide are based on their suitability to the region. It also brings to attention that few models like PESERA, EUROSEM and WEPP are mostly being used concentrated in a particular region. Models like PESERA and EPM are mostly used in European region and may be encouraged to estimate soil erosion in Himalayan region. The review also highlights lack of studies with inclusion of water quality as an important parameter while assessing soil erosion vulnerability in the region. The review suggests that in case of lack of data, various statistical methods like PCA, CF, FUZZY etc. can be preferred for qualitative assessment over quantitative assessment. Considering availability of accurate input, researchers need to attempt more methods and perform comparative studies to attain accurate results for assessing soil erosion vulnerability leading to strategizing soil conservation in fragile regions.

Corporations are frequently seeking different methods to increase their earnings per share and diversified acquisition has become a major means for profitability and growth. This article will explore how a corporation can increase its growth and profits through acquisitions and mergers in todays complex business environment.