Research on forming quality of poly-wedge pulley spinning

As an important power transmission part, pulleys are widely used in automobile industry, agricultural machinery, pumps and machines. A near-net forming process for six-wedge belt pulleys manufacturing was put forward. For this purpose, the required tooth shape and size can be formed directly by spinning without machining. The whole manufacturing procedures include blanking, drawing and spinning. The spinning procedure includes five processes, performing, drumming, thickening, toothing and finishing. The forming defects occurred during each forming processes of poly-wedge pulley spinning, such as the drumming failure, flanged opening-end, folded side-wall, insufficient bottom size, flashed opening-end, cutting-off bottom, are introduced, and the factors influencing the defects are analyzed. The corresponding preventive measures are put forward

Alteration Detection of Tensor Dependence Structure via Sparsity-Exploited Reranking Algorithm

Tensor-valued data arise frequently from a wide variety of scientific applications, and many among them can be translated into an alteration detection problem of tensor dependence structures. In this article, we formulate the problem under the popularly adopted tensor-normal distributions and aim at two-sample correlation/partial correlation comparisons of tensor-valued observations. Through decorrelation and centralization, a separable covariance structure is employed to pool sample information from different tensor modes to enhance the power of the test. Additionally, we propose a novel Sparsity-Exploited Reranking Algorithm (SERA) to further improve the multiple testing efficiency. The algorithm is approached through reranking of the p-values derived from the primary test statistics, by incorporating a carefully constructed auxiliary tensor sequence. Besides the tensor framework, SERA is also generally applicable to a wide range of two-sample large-scale inference problems with sparsity structures, and is of independent interest. The asymptotic properties of the proposed test are derived and the algorithm is shown to control the false discovery at the pre-specified level. We demonstrate the efficacy of the proposed method through intensive simulations and two scientific applications

Sustainable Design Framework for Enhancing Shear Capacity in Beams Using Recycled Steel Fiber-Reinforced High-Strength Concrete

According to a recent estimate, over 1.5 billion wasted tyres which containing over 40 % of vulcanised rubber and 15% of steel fibre are discarded yearly, which posing a serious threat to circular economy implementation and transition to net zero. To minimise the greenhouse gas(GHG) emission and the environmental side effect caused by burning and burying these waste tyres, recycling and reusing these materials for sustainable structural designs has become the centre of attention. This paper focuses on applying recycled bead steel fibre to improve the shear capacity of fibre-reinforced concrete beams. Moreover, the existing national standard known as Eurocode 2 and TR63 can hardly illustrate the relationship between fibre and high-strength concrete. This study is the first to investigate shear behaviours of high-strength industrial and recycled steel fibre reinforced concrete beams with consideration of different shear span ratios. Therefore, twenty real-scale beams are constructed to examine the shear capacity of high-strength industrial and recycled steel-fibre reinforced concrete beams, which aims to compare the improvement of shear strength through experiments and identify different shear strength improvements of the two categories of steel fibre. Besides, comprehensive data of 164 beams from previous studies have been collected to benchmark with the experimental results for the formula design. This study proves the feasibility of replacing industrial steel with recycled steel fibre to improve the shear capacity of fibre-reintroduced concrete beams. Moreover, there are six novel equations designed developed using Eurocode 2 and TR63 as a basis in this study. Based on the findings of the paper, the proposed formulas demonstrate remarkable accuracy, with an average value of 0.982 and standard deviation of 0.213, respectively. Following an exhaustive comparison of RSF and ISF reinforced concrete beams, with a focus on economic expenditure and GHG emissions, it can be concluded that RSF offers superior economic and environmental benefits, which reduce the emissions up to 25.39% and price up to 28.04% when replacing ISF 0.8% RSF, respectively

Sustainable Design Framework for Enhancing Shear Capacity in Beams Using Recycled Steel Fiber-Reinforced High-Strength Concrete

According to a recent estimate, over 1.5 billion wasted tyres which containing over 40 % of vulcanised rubber and 15% of steel fibre are discarded yearly, which posing a serious threat to circular economy implementation and transition to net zero. To minimise the greenhouse gas(GHG) emission and the environmental side effect caused by burning and burying these waste tyres, recycling and reusing these materials for sustainable structural designs has become the centre of attention. This paper focuses on applying recycled bead steel fibre to improve the shear capacity of fibre-reinforced concrete beams. Moreover, the existing national standard known as Eurocode 2 and TR63 can hardly illustrate the relationship between fibre and high-strength concrete. This study is the first to investigate shear behaviours of high-strength industrial and recycled steel fibre reinforced concrete beams with consideration of different shear span ratios. Therefore, twenty real-scale beams are constructed to examine the shear capacity of high-strength industrial and recycled steel-fibre reinforced concrete beams, which aims to compare the improvement of shear strength through experiments and identify different shear strength improvements of the two categories of steel fibre. Besides, comprehensive data of 164 beams from previous studies have been collected to benchmark with the experimental results for the formula design. This study proves the feasibility of replacing industrial steel with recycled steel fibre to improve the shear capacity of fibre-reintroduced concrete beams. Moreover, there are six novel equations designed developed using Eurocode 2 and TR63 as a basis in this study. Based on the findings of the paper, the proposed formulas demonstrate remarkable accuracy, with an average value of 0.982 and standard deviation of 0.213, respectively. Following an exhaustive comparison of RSF and ISF reinforced concrete beams, with a focus on economic expenditure and GHG emissions, it can be concluded that RSF offers superior economic and environmental benefits, which reduce the emissions up to 25.39% and price up to 28.04% when replacing ISF 0.8% RSF, respectively