Global sensitivity analysis and aggregation of risk in multi-product supply chain networks

Manufacturing firms manage complex supply chain networks which are exposed to a plethora of hazard events. An essential part of the risk management process is the calculation of the stand-alone risk exposures of the product-specific supply chains, but also of the entire multi-product system. In this paper, first, a global sensitivity analysis of the statistical supply chain risk model is conducted. This method helps the decision-makers to understand the risk of the model they are using. Second, a methodology for risk aggregation in multi-product supply chain networks is proposed. The real-world data is used to analyse and validate the model. Supply chain managers equipped with the proposed method will better cope with the risk in supply chains for different product configurations.     

A secure and privacy-preserving lightweight authentication protocol for wireless communications

In wireless networks, seamless roaming allows a mobile user (MU) to utilize its services through a foreign server (FS) when outside his home server (HS). However, security and efficiency of the authentication protocol as well as privacy of MUs are of great concern to achieve an efficient authentication protocol. Conventionally, authentication involves the participation of three entities (MU, HS, and FS); however, involving an HS in the authentication process incurs heavy computational burden on it due to huge amount of roaming requests. Moreover, wireless networks are often susceptible to various forms of passive and active attacks. Similarly, mobile devices have low processing, communication, and power capabilities.

In this paper, we propose an efficient, secure, and privacy-preserving lightweight authentication protocol for roaming MUs in wireless networks without engaging an HS. The proposed authentication protocol uses unlinkable pseudo-IDs and lightweight time-bound group signature to provide strong user anonymity, and a cost-effective cryptographic scheme to achieve security of the authentication protocol. Similarly, we implement a better billing system for MUs and a computationally efficient revocation scheme. Our analysis shows that the protocol has better performance than other related authentication protocols in wireless communications in terms of security, privacy, and efficiency.     

Surface Chemistry Dictates the Osteogenic and Antimicrobial Properties of Palladium-, Platinum-, and Titanium-Based Bulk Metallic Glasses

Titanium alloys are commonly used as biomaterials in musculoskeletal applications, but their long-term efficacy can be limited by wear and corrosion, stress shielding, and bacterial colonization. As a promising alternative, bulk metallic glasses (BMGs) offer superior strength and corrosion resistance, but the influence of their chemical composition on their bioactivity remains largely unexplored. This study, therefore, aims to examine how the surface chemistry of palladium (Pd)-, platinum (Pt)-, and titanium (Ti)-based BMGs can steer their response to biological systems. The chemical composition of BMGs governs their thermophysical and mechanical properties, with Pd-based BMGs showing exceptional glass-forming ability suitable for larger implants, and all BMGs exhibiting a significantly lower Young's modulus than Ti-6Al-4 V (Ti64), suggesting a potential to reduce stress shielding. Although BMGs feature copper depletion at the near surface, their surface chemistry remains more stable than that of Ti64 and supports blood biocompatibility. Fibrin network formation is heavily dependent on BMGs’ chemical composition and Ti-based BMGs support thicker fibrin network formation than Ti64. Furthermore, BMGs outperform Ti64 in promoting mineralization of human bone progenitor cells and demonstrate antimicrobial properties against Staphylococcus aureus in a surface chemistry-dependent manner, thereby indicating their great potential as biomaterials for musculoskeletal applications.     

Analysis of fractional Navier–Stokes equations

In this study, we apply the fractional Laplace variational iteration method (FLVIM), a computer methodology for exploring fractional Navier–Stokes equation solutions. In light of the theory of fixed points and Banach spaces, this paper also explores the uniqueness and convergence of the solution of general fractional differential equations obtained by the suggested method. In addition, the fractional Laplace variational iteration method solution's error analysis is covered. The computational technique also clearly demonstrates the validity and dependability of the suggested method for solving fractional Navier-Stokes equations. Furthermore, the obtained solutions are a perfect fit with previously established solutions.     

Chemical Recycling of Polyolefins with the Molten Metal Reactor at 460 °C

This paper describes the pyrolysis of high-density polyethylene (HDPE) in a molten metal reactor, where the HDPE is initially in direct contact with molten metal at 460 °C. Due to the equal temperature across the molten metal, secondary reactions are minimised, and long-chain waxes with boiling points over 600 °C accumulate on the molten metal. Once enough wax has accumulated, further HDPE pyrolysis occurs within the wax in a direct heat transfer reaction.     

Single- and multi-GPU computing on NVIDIA- and AMD-based server platforms for solidification modeling application

This work explores the performance of single- and multi-GPU computing on state-of-the-art NVIDIA- and AMD-based server-class hardware using various programming interfaces to accelerate a real-world scientific application for solidification modeling based on the phase-field method. The main computations of this memory-bound application correspond to 20 stencils computed across grid nodes. We investigate the application's scalability for two basic schemes of organizing computation: without and with hiding data transfers behind computation, combined with using either peer-to-peer inter-GPU data transfers through NVIDIA NVLink and AMD Infinity interconnects or communication over the PCIe and main memory. Among the studied programming interfaces is CUDA, HIP, and OpenMP Accelerator Model. While the first two are designed to write the codes for a specific hardware platform, OpenMP enables code portability between NVIDIA and AMD GPUs. The resulting performance is experimentally assessed on computing platforms containing NVIDIA V100 (up to 8 GPUs) and A100 (one GPU), as well as AMD MI210 (one device) and MI250 (up to 8 logical GPUs).     

Hybrid rubber-concrete isolation slab system with various shape factors for structures subjected to horizontal and vertical vibrations

The present framework proposed the development of a Hybrid Rubber-Concrete Isolation Slab System (HRCISS) to support building structures subjected to horizontal and vertical vibration due to ground motion and machine or equipment operation in the structure. Given that the effect of the shape factor on both horizontal and vertical stiffness has yet to be reported, the proposed composite system was comprised of two layers under the nodal points of the upper layer near the slab corners with four High Damping Rubber (HDR) components positioned between the slab layers to dissipate multidirectional (horizontal and vertical directions) vibrations. The ABAQUS software was utilized to model the finite element model (FEM) and simulate the HRCISS subjected to cyclic horizontal and vertical displacements. For the optimal HDR design, the model was applied in five 3-story buildings, and the effect of distinct shape factors (0 $<$ S $<$ 2) of the HDR bearings—the ratio of bearing's loaded area to unloaded area (free to bulge)—within the hybrid system was evaluated. For each building with a specific HDR shape factor, the HRCISS was installed in the first, second, and third stories, separately, to investigate the influence of the installation level of the isolation system on the overall structural performance. The multistory buildings were subjected to two types of vibration loads: the interior machine-induced vibrations, and the exterior seismic-induced vibrations in the horizontal and vertical directions. Based on the results, the FEM results proved the significant influence of the shape factors on the dynamic response of the HRCISS under both interior and exterior 3D vibrations when applied in multistory buildings. The lateral drift of the three-story one-bay buildings decreased with the decrement of shape factor with buildings of HRCISS installed in 1st story recording more reduction. Moreover, the deflection in the structural slab under the HRCISS decreased for lower shape factor bearings. Nevertheless, the reduced deflection was less affected by the level of the machine-equipped story. The rubber layer also stiffened in shear and compression directions with a higher shape factor.     

A Spiky Silver-Iron Oxide Nanoparticle for Highly Efficient Targeted Photothermal Therapy and Multimodal Imaging of Thrombosis

Thrombosis and its complications are responsible for 30% of annual deaths. Limitations of methods for diagnosing and treating thrombosis highlight the need for improvements. Agents that provide simultaneous diagnostic and therapeutic activities (theranostics) are paramount for an accurate diagnosis and rapid treatment. In this study, silver-iron oxide nanoparticles (AgIONPs) are developed for highly efficient targeted photothermal therapy and imaging of thrombosis. Small iron oxide nanoparticles are employed as seeding agents for the generation of a new class of spiky silver nanoparticles with strong absorbance in the near-infrared range. The AgIONPs are biofunctionalized with binding ligands for targeting thrombi. Photoacoustic and fluorescence imaging demonstrate the highly specific binding of AgIONPs to the thrombus when functionalized with a single chain antibody targeting activated platelets. Photothermal thrombolysis in vivo shows an increase in the temperature of thrombi and a full restoration of blood flow for targeted group but not in the non-targeted group. Thrombolysis from targeted groups is significantly improved (p < 0.0001) in comparison to the standard thrombolytic used in the clinic. Assays show no apparent side effects of AgIONPs. Altogether, this work suggests that AgIONPs are potential theranostic agents for thrombosis.