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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. [ABSTRACT FROM AUTHOR]

This paper presents the surface degradation analysis of contact tips of commercial (20A, 110 V) molded case circuit breaker due to multiple electrical interruptions during experimental electrical test. In the experimental electric test, and according to the post arc current observation, the arc voltage and current were categorized. Multiple high-current interruption has been identified, and the phenomena that regulate the interruption failure have been established. Also, post-arc current sprinted for a short period of time (10–200 µs) during multiple electrical interruptions. These interruptions cause the failure of the contact tips of MCCB. The metallurgical changes were also observed on the contact tips. The braze joints between contacts tips and copper base is also affected by thermal and electrical conductivity during the electrical interruptions. The optical microscope reveals the typical metallurgical changes that occur during a breakdown, such as surface degradation, wear, cracks adjacent to the braze interface, oxide layer formation, cracks on the contact tips, and cracks that penetrate into the copper base. The experimental investigation of the factors influencing the post arc current was carried out to learn more about the link between the post arc current and the degradation of the interruption characteristics. This investigation's primary objective is to explore the interruption performance and failure analysis of commercial MCCBs. [ABSTRACT FROM AUTHOR]

Background: Bone cancer is a severe condition often leading to patient mortality. Diagnosis relies on X-rays, MRIs, or CT scans, which require time-consuming manual review by experts. Thus, developing an automated system is crucial for accurate classification of malignant and healthy bone. Methods: Differentiating between them poses a challenge as they may exhibit similar physical characteristics. The initial step is selecting the optimal edge detection method. Two feature sets are then generated: one with the histogram of oriented gradients (HOG) and one without. Performance evaluation involves two machine learning models: Support Vector Machine (SVM) and Random Forest. Results : Including HOG consistently yields superior results. The SVM model with HOG achieves an F-1 score of 0.92, outperforming the Random Forest model's.77. This study aims to develop reliable methods for bone cancer classification. The proposed automated method assists surgeons in accurately detecting malignant bone regions using modern image analysis techniques and machine learning models. Incorporating HOG significantly enhances performance, improving differentiation between malignant and healthy bone. Conclusion : Ultimately, this approach supports precise diagnoses and informed treatment decisions for bone cancer patients. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]