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The purpose of this paper is to study the influence of Zr content on immersion and electrochemical corrosion behavior of Zr-containing Ti-based (TiZr) alloys.

The phase analysis of as-cast TχZAB alloys was carried out using X-ray diffraction. The microstructure of corrosion surfaces of the samples was observed using optical metallographic microscopy and scanning electron microscopy, equipped with energy dispersive spectroscopy.

The immersion test reveals that the corrosion is alleviated in the presence of a high amount of Zr, whereas pitting corrosion occurs when the Zr content is up to 40 Wt.%. Furthermore, the electrochemical analysis demonstrates that the corrosion resistance TiZr alloys is improved with increasing Zr content.

The TiZr alloys are promising candidates for high-end applications because of their excellent comprehensive properties. These alloys are usually used in marine or other harsh corrosive environments; therefore, it is essential to study their corrosion behavior.

Paediatric congenital esophageal atresia surgery typically requires delicate and dexterous operations in a narrow and confined workspace. This study aims to develop a novel robot assisted surgical system to address these challenges.

The proposed surgical robot consists of two symmetrical slave arms with nine degree of freedoms each. Each slave arm uses a rigid-dexterous configuration and consists of a coarse positioning manipulator and a distal fine operation manipulator. A small Selective Compliance Assembly Robot Arm (SCARA) mechanism was designed to form the main component of the coarse positioning unit, ensuring to endure large forces along the vertical direction and meet the operational demands. The fine positioning manipulator applied the novel design using flexible shafts and universal joints to achieve delicate operations while possessing a high rigidity. The corresponding kinematics has been derived and then was validated by a co-simulation that was performed based on the combined use of Adams and MATLAB with considering the real robot mass information. Experimental evaluations for the tip positioning accuracy and the ring transfer tasks have been performed.

The simulation was performed to verify the correctness of the derived inverse kinematics and demonstrated the robot’s flexibility. The experimental results illustrated that the end-effector can achieve a positioning accuracy within 1.5 mm in a confined 30 × 30 × 30 mm workspace. The ring transfer task demonstrated that the surgical robot is capable of providing a solution for dexterous tissue intervention in a narrow workspace for paediatric surgery.

A novel and compact surgical assist robot is developed to support delicate operations by using the dexterous slave arm. The slave arm consists of a SCARA mechanism to avoid experiencing overload in the vertical direction and a tool manipulator driven by flexible shafts and universal joints to provide high dexterity for operating in a narrow workspace.

The objective of this paper is to compare and evaluate the environmental performance of steel supply chains considering relevant environmental loss factors using Taguchi loss function (TLF) and design of experiments (DOE).

The different environmental loss factors in steel manufacturing supply chain were studied and the significant factors were identified. Their combined contributions along the significant factors were estimated using TLF and DOEs comparing environment losses at different scenarios.

The proposed methodology using TLF and DOEs was applied to three Indian steel manufacturing companies (Company A, Company B and Company C). The Company A with minimal average environmental loss score is found to be operating its supply chain with higher efficiency and has better environmental performance compared to the other two companies (B and C).

The results obtained are based on the study carried out in three Indian steel manufacturing companies. Therefore, the results cannot be generalized.

This paper will definitely show the direction for comparative environmental performance assessment of manufacturing industries in general and steel industries in specific considering environmental loss factors and environmental conditions. It determines individual performance across each environmental loss factor and their combined impact.

Although there is a need to have comparative performance analysis with respect to environmental losses among steel companies in developing countries such as India, but hardly any study has been reported in this direction. This work will definitely add the value to the supply chain literature in general and environment losses in steel manufacturing supply chain in specific.