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Objectives. Current research aims to identify factors that affect the occupational safety climate in university laboratories despite their perception as low-risk areas compared to industrial environments. Methods. A safety climate survey was conducted in science laboratories across various engineering universities in Pakistan. The survey questionnaire was administered to 406 personnel, and a quantitative method for analysis was selected to examine the socio-demographic variables. A 5-point Likert scale (1 = strongly disagree to 5 = strongly agree) was used to perceive responses from participants. Additionally, a scale reliability test was conducted, and multivariate analysis of variance was performed to determine the relationship between selected dependent and independent variables. Results. The study found an overall safety climate score of 3.16 ± 0.55, indicating a moderate to high perception of safety on a scale of 1–5. Parameters such as role in the laboratory, departments/disciplines, accident experience and safety training significantly affected the safety climate score, while gender, age group, duration in university and accident witnessing did not. Conclusion. Upper management involvement, safety communication and direct supervision are crucial for improving the safety climate of university laboratories. The study recommends the consideration of the identified significant safety climate dimensions in laboratory safety policy-making at academic institutes. [ABSTRACT FROM AUTHOR]

In recent years, the reliable, accurate, and timely estimate of product cost at the conceptual design stage can enhance the competitiveness of a casting part. Set‐based concurrent engineering has emerged as an efficient solution to overcome this limitation as it provides simultaneous design procedures to positively assist the designer in achieving the required customer values in a short time and low cost. Therefore, this study attempts to integrate the set‐based concurrent engineering methodology into the development of a cost modeling system for the metal casting process. The system architecture is comprised of a user interface, knowledge database, and CAD modeling system. A detailed working flow process of the developed cost modeling system has been proposed under the guidelines of set‐based concurrent engineering. Further, the proposed methodology is demonstrated and validated by employing a real‐time casting part that was manufactured using the sand casting process. The implementation of the system provided many tangible benefits to the collaborative company including a decrease in cost estimation time (∼50%) and part rejection rate (∼32.3%). Further, the developed cost modeling approach provided a cost estimate near the actual cost of the product (∼4% deviation). It truly proves the significance of the developed system for the practitioners who believe that accurate and timely estimates of product manufacturing cost at the design stage can enhance the competitiveness of a product. [ABSTRACT FROM AUTHOR]

Peculiar characteristics of squeeze casted hybrid aluminum matrix composites (AMCs) enable it as an appropriate candidate for various manufacturing applications but also make their machining challenging. For that reason, wire electric discharge machining (WEDM) has been preferred over conventional machining processes for the cutting squeeze casted Al2024/Al2O3/W hybrid composite in this study. The presence of nanoparticles in the material affects the machining performance of wire electrodes. Therefore, molybdenum and zinc-coated wires have been chosen, and cryogenic treatment has been applied to improve their machining performance. To analyze the effects of cryogenic treatment, the machining efficiency of cryogenic treated (CT) wire has been compared with non-treated (NT) wire. Besides wire type, four key input variables including pulse duration (TON), wire feed rate (FR), wire runoff speed (SW), and wire tension (TW) have also been optimized to improve the imperative response measures including cutting speed (CS), surface roughness (SR), and kerf width (KW). Microstructural analysis of NT wire depicts a high concentration of micro-voids, micro-cracks, and deep craters, while the surface of CT wire has been observed relatively fine after the machining. Comparative analysis of both wire electrodes has declared that CT wire yields 26.96% and 15.10% superior results for CS and SR respectively, and 6.92% deprived results for KW than NT wire. Grey relational analysis (GRA) has been practiced for multi-objective optimization and presented TON = 3 μs, FR = 13 m/min, SW = 11 m/min, and TW = 10 g as an optimal set of input variables to achieve 75.1% and 72.5% overall results with NT and CT wire, respectively. [ABSTRACT FROM AUTHOR]