Lug Joint is a typical connecting structure in the engineering field, which is often used to connect different components. Analyzing lug stresses is crucial for structural integrity and failure understanding. This study focuses on investigating the stress concentration factor and displacements of different types of lug joints under axial loading. Lug modelling in SolidWorks, results via Finite Unit Analysis plug-in. The ESDU files will be used as validation and compared with the obtained results to ensure the reliability of the experiments. This study compared the structural performance of a waisted lug and a waisted lug with additional flat (or called: flat-sided lug) under different geometric ratio conditions (a/w and t/d). The flat-sided lug consistently exhibited lower stress concentration factors (SCF) and smaller displacements, which indicate greater bearing capacity and less deformation, although it the volume and weight larger than the waisted lug. The different lugs exhibited similar behaviour with respect to t/d, showing a continuous improvement until reaching the medium thickness range, after which performance began to deteriorate at higher thicknesses due to bending effects. Overall, the flat-sided lug shows superior mechanical performance. However, the final design must strike a balance between these advantages and physical and economic considerations.

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As high-performance computing, artificial intelligence, and power-electronic devices continue to evolve toward higher integration and power density, localized chip hotspots impose increasingly severe thermal constraints. Conventional air cooling and heat-spreading-only solutions are becoming insufficient to simultaneously remove high heat fluxes and maintain temperature uniformity. Microchannel liquid cooling offers a large surface-area-to-volume ratio, short heat-transfer paths, and high volumetric heat-transfer capability. In particular, manifold microchannels shorten the effective flow length and reshape coolant distribution, providing a promising route for cooling chips under high and spatially non-uniform heat loads. Based on a thorough revision of the original manuscript, this review discusses the development of microchannel heat sinks, geometric parameters and flow-distribution mechanisms of manifold structures, hotspot-oriented cooling strategies, field-synergy and secondary-flow mechanisms, thermal response under dynamic boundary conditions, multiphysics simulation, and advanced manufacturing. Current studies indicate that manifold structures can reduce streamwise pressure losses while improving local heat transfer; however, their performance strongly depends on the coupled manifold-microchannel geometry, flow uniformity, and operating boundary conditions, and no universal optimum geometric parameter exists independently of the specific application. Future work should focus on adaptive flow control for dynamic hotspots, chip-cooler co-design, two-phase and advanced coolants, data-driven optimization, and integrated additive manufacturing to move manifold microchannel cooling from high-performance prototypes toward reliable and scalable engineering systems.

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Compared to traditional titanium alloy blades, CFRP blades offer higher specific strength and specific stiffness, fatigue performance, and greater design flexibility in terms of structural geometry.This paper employs a literature review approach to discuss the theoretical foundations, engineering examples, limiting factors, and potential future developments related to CFRP resin-matrix composites. The analytical method first examines the principles of material reinforcement, damage tolerance, and the relationship between manufacturing methods and performance. Subsequently, composite fan designs from the GE90, GEnx, GE9X, and Rolls-Royce families are studied as typical examples to illustrate their progression from experimentation to practical engineering applications.Furthermore, the advantages and challenges of CFRP fan blades are comprehensively summarized from the perspectives of mechanics, manufacturing, and maintenance. Finally, future research directions are proposed regarding smart manufacturing, multistage damage models, interface optimization, and multifunctional composite systems. This review demonstrates that carbon fiber-reinforced polymer fan blades have become an integral part of the new generation of aero-engines; however, manufacturing consistency, impact resistance, and life prediction still require further improvement.

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Two-dimensional transition-metal dichalcogenides have become important candidate materials for post-silicon semiconductors and optoelectronic devices because of their atomic-scale thickness, tunable band gaps, and good device compatibility. The electronic structure of monolayer MoS₂ is highly sensitive to strain. In-plane biaxial strain can continuously tune both the magnitude and the direct/indirect character of the band gap by changing Mo–S bond lengths and orbital hybridization. Based on density-functional theory, this work systematically performs first-principles calculations on the electronic structure of monolayer 1H-MoS₂ under biaxial strains from −6% to +8% in Quantum ESPRESSO, using the PBE functional and PAW pseudopotentials. At each strain point, ionic relaxation, self-consistent field calculation, and Γ–K–M–Γ band analysis are completed, and the fundamental gap, the K–K direct gap, and the Γ–K indirect gap are extracted simultaneously. The results show that under −2% compressive strain the system exhibits a K–K direct gap with a fundamental gap of 1.890 eV; near zero strain the K–K and Γ–K gaps are nearly degenerate (1.686 eV and 1.667 eV, respectively); after entering the tensile regime, the valence-band maximum shifts to Γ while the conduction-band minimum remains at K, forming a stable indirect gap, and the fundamental gap decreases monotonically from 1.667 eV at 0% to 0.589 eV at +8%. Gaps on the compressive side remain overall larger and reach a maximum of 1.919 eV at −4% within the present scan. This study provides a reproducible strain–band-gap relation and transition criterion, and offers a benchmark for band-gap engineering of two-dimensional MoS₂ and for subsequent higher-accuracy calculations.

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