No abstract

When modern FPGA architecture becomes increasingly complicated, modern FPGA placement is a mixed optimization problem with multiple objectives, including wirelength, routability, timing closure, and clock feasibility. Typical FPGA devices nowadays consist of heterogeneous SLICEs like SLICEL and SLICEM. The resources of a SLICE can be configured to {LUT, FF, distributed RAM, SHIFT, CARRY}. Besides such heterogeneity, advanced FPGA architectures also bring complicated constraints like timing, clock routing, carry chain alignment, etc. The above heterogeneity and constraints impose increasing challenges to FPGA placement algorithms.In this work, we propose a multi-electrostatic FPGA placer considering the aforementioned SLICEL-SLICEM heterogeneity under timing, clock routing and carry chain alignment constraints. We first propose an effective SLICEL-SLICEM heterogeneity model with a novel electrostatic-based density formulation. We also design a dynamically adjusted preconditioning and carry chain alignment technique to stabilize the optimization convergence. We then propose a timing-driven net weighting scheme to incorporate timing optimization. Finally, we put forward a nested Lagrangian relaxation-based placement framework to incorporate the optimization objectives of wirelength, routability, timing, and clock feasibility. Experimental results on both academic and industrial benchmarks demonstrate that our placer outperforms the state-of-the-art placers in quality and efficiency.

Accompanied by the concept of supply-side structural reform and conversion of new and old driving energy to create a new round of economic development in China, cement supplier evaluation and selection are increasingly crucial for concrete production plants, ensuring not only raw material supply with high quality and at a reasonable price but also sustainable and long-term cooperation with suppliers. Given the limitations of the existing approaches, this study proposes a cement supplier evaluation and selection framework based on the combination of the improved FAHP-CRITIC method and VIKOR method. We first develop a cement supplier evaluation and selection index system under the background of new and old driving energy conversion, including eight first-level indicators and twenty-one second-level indicators. The proposed model then uses triangular fuzzy numbers AHP (TFN-AHP) and the improved CRITIC method to calculate subjective and objective weights by replacing the coefficient of variation with standard deviation, uses the ideal solution-based method to determine their combination weights, and combines the VIKOR method to calculate the comprehensive evaluation values of candidate cement suppliers. After that, the proposed approach is applied to evaluate and select ten cement suppliers for concrete production plants, and the results are compared and analyzed with those using the traditional method. The results of the comparison show that the proposed strategy can be scientific and reliable, helping managers to make the right decision under the background of new and old driving energy conversion in China.