Dynamic response of hybrid carbon fibre laminate beams under ballistic impact

This novel hybrid fibre composites combining stiff composites with soft composites are developed to improve the ballistic impact resistance of composite beams while maintaining good quasi-static loading bearing capacity. The ballistic impact performance of the hybrid beams have been investigated experimentally at a projectile velocity range of , including ballistic limits, failure modes, energy absorption capacity and the interaction between stiff and soft composite parts. For each type of monolithic beams, i.e. stiff, soft and hybrid monolithic beams, three categories of failure modes have been identified: minor damage with rebound of projectile at the low impact velocities, fracture of beam at the medium impact velocities and perforation of beam at the high impact velocities. The critical velocity of hybrid monolithic beam was similar to that of the soft monolithic beam under the same failure mode, and higher than that of the stiff monolithic beam. For the sandwich beams with stiff, soft and hybrid face sheets, the failure modes were similar to those of the monolithic beams. Among the monolithic beams, the hybrid and soft monolithic beams exhibited better energy absorption capacity than the stiff monolithic beams. As for the sandwich beams, the hybrid-face sandwich beams absorbed more kinetic energy of projectile than the soft-face sandwich beams at higher projectile velocity. The advantages of the stiff/soft hybrid construction include: (i) at lower impact velocity, the soft composite part survived with negligible damage under impact; (ii) due to the buffer effect of the soft part at the front face, stress distribution within the stiff part of the hybrid monolithic beams is more uniform than that of the stiff monolithic beams

Comparative study and optimal design of alternative PM configuration transverse flux linear machine

This paper presents the comparative study and optimal design of a transverse flux linear machine with different PM configurations, viz. surface-mounted and consequent-pole, in which the consequent-pole version is firstly proposed. Firstly, the effect of variation of the main design parameters on both topologies are studied. Then, the multi-objective optimization method based on genetic algorithm combined with response surface methodology (RSM) is adopted to realize the optimal design of these two topologies and Pareto front solutions will be obtained. Finally, the characteristics of these two topologies are analyzed and compared, with particular regard to the advantages and disadvantages of the consequent pole topology

Multi-domain optimization of high power-density PM electrical machines for system architecture selection

The power density of electrical machines for transport applications has become a critical aspect and target of optimization. This paper looks at the development of an intelligent, rapid, flexible, and multidomain tool to aid for system-level optimization of electrical machines within next-generation high power density applications. The electromagnetic, thermal, and mechanical aspects are wholly integrated, thus enabling the optimization including the nonactive mass. The implementation and overall architecture of the tool are described, and using a case study drawn fromthe aerospace industry, the tool is used to compare the power density of various surface permanentmagnet topologies including single airgap and dual airgapmachines, highlighting the particular suitability of the dual rotor topology in achieving the best power to mass ratio. Finally, the accuracy of the tool is highlighted by practical realization and experimental validation

Analytical Model of Modular Spoke-Type Permanent Magnet Machines for In-Wheel Traction Applications

This paper proposes an analytical model of modular spoke-type permanent magnet (MSTPM) machines based on air-gap field modulation (AFM) theory. Firstly, a fundamental AFM model of open-circuit MSTPM machines is introduced. The open-circuit air-gap field of MSTPM machines is determined by three fundamental elements including the primitive magnetizing magnetomotive force (MMF) produced by permanent magnet (PM), and two modulators which consist of stator and rotor permeance. The analytical MMF excited by PM (PM-MMF) can be calculated by using magnetic circuit method, while the stator and rotor permeance models are developed based on relative permeance (RP) method. Thereafter, a general model is proposed to calculate the open-circuit back electromotive force (EMF) of MSTPM machines. Further, the winding inductance model is established on the basis of equivalent magnetic circuit method and RP model. Finally, the machine performance is predicted by the analytical model, and verified by both finite element analysis (FEA) and experimental results

INFO3333 GROUP ASSIGNMENT Group 61 (Prac 13 Tue 3pm CC)

This literature review will analyse, examine, and confirm all the information included in the literature from 2013 to 2021 is recent, relevant, and correct. Our project, classroom AR integration, aims to allow remote students to join the class through VR imaging and to project the remote students into the classroom as in-campus students through AR. The main objective is to enable two modes (online and on-campus) of teaching to work generally as conventional, allowing diverse and flexible learning styles

Sensitivity analysis of machine components thermal properties effects on winding temperature

This paper investigates the sensitivity analysis of winding temperature to key parameters in electrical machine thermal design. With a validated 3D thermal model based on an existing 75kW traction machine for an electric vehicle, the methodology of the sensitivity analysis study is conducted and presented. Finally, further research and practical guidelines on reducing the peak temperature of electrical machines are proposed

Equivalent slot thermal conductivity and back-iron extension effects on machine cooling

Back-iron Extension (BIE) is an effective thermal management technique which reduces the winding temperatures by projecting part of the back iron into the center of slot, thereby shortening the heat transfer path between the coil and back iron. Based on an existing concentrated-wound traction motor, this paper investigates the effects of equivalent slot thermal conductivity of coil on the optimal back iron extension geometry and temperature reduction

Beyond Semantics: Learning a Behavior Augmented Relevance Model with Self-supervised Learning

Relevance modeling aims to locate desirable items for corresponding queries, which is crucial for search engines to ensure user experience. Although most conventional approaches address this problem by assessing the semantic similarity between the query and item, pure semantic matching is not everything.Comment: Partial conten

The tumor burden score may be a discriminator in microwave ablation versus liver resection for hepatocellular carcinoma within the Milan criteria: a propensity score matching and inverse probability of treatment weighting study

PurposeThis study aims to compare the prognostic outcome of resection (RES) and microwave ablation (MWA) in different tumor burden score (TBS) cohorts.Patients and MethodsWe retrospectively analyzed 479 patients with primary hepatocellular carcinoma (HCC) who underwent RES (n = 329) or MWA (n = 150) with curative intent at our institution. We assessed their overall survival (OS) and progression-free survival (PFS) using the Kaplan–Meier curve. Propensity score matching (PSM) and inverse probability of treatment weighting (IPTW) were performed to minimize selection and confounding biases. Multivariate Cox regression was used to define the association between surgical modalities and outcomes.ResultsFollowing PSM, in the TBS ≤3 cohort, the cumulative 1-, 3-, 5- year OS in the RES and MWA groups were 92.5% vs. 98.8%, 82.7% vs. 90.0%, and 82.7% vs. 83.2% (P = 0.366), respectively. The corresponding PFS rates in the RES and MWA groups were 82.7% vs. 88.0%, 63.6% vs. 68.3% and 55.2% vs. 56.3, respectively (P = 0.218). In the TBS >3 cohort, the cumulative 1-, 3-, 5- year OS between the RES and MWA groups were 92.5% vs. 95.0%, 82.8% vs. 73.2% and 76.3% vs. 55.1%, (P = 0.034), respectively. The corresponding PFS rates in the RES and MWA groups were 78.0% vs. 67.5%, 63.6% vs. 37.5% and 55.2% vs. 37.1%, respectively (P = 0.044). The IPTW analysis showed similar results as shown in PSM analysis. The multivariate Cox regression indicated that the type of surgical modality was not associated with a poorer prognostic outcome in the TBS ≤3 cohort, unlike in the TBS >3 cohort.ConclusionTBS, as a discriminator, might help guide treatment decision-making for HCC within the Milan criteria