In order to precisely retrieve the atmospheric CO2 , a retrieval method based on both near infrared (NIR) and thermal infrared (TIR) is established firstly. Then a look-up-table (LUT) based fast line-by-line rad...In order to precisely retrieve the atmospheric CO2 , a retrieval method based on both near infrared (NIR) and thermal infrared (TIR) is established firstly. Then a look-up-table (LUT) based fast line-by-line radiative transfer model (RTM) was integrated into the retrieval procedure to accelerate radiative transfer calculations. The LUT stores gas absorption cross-sections as a function of temperature, pressure and wavenumber. It could greatly reduce calculating time in radiative transfer compared to direct line-by-line method. Then retrieval was simulated using NIR, TIR and both bands. The retrieved CO2 profiles suggest joint approach could reconstruct CO2 profile better than those using NIR or TIR alone. Joint retrieval using both bands simultaneously could provide better constrain to CO2 vertical distribution in the whole troposphere.展开更多
A new hybrid FPGA architecture is proposed. The logic tile,which consists of a logic cluster and related connection boxes (CBs), can be configured as either programmable logic arrays (PLAs) or look-up tables (LUT...A new hybrid FPGA architecture is proposed. The logic tile,which consists of a logic cluster and related connection boxes (CBs), can be configured as either programmable logic arrays (PLAs) or look-up tables (LUTs), This architecture can be classified as an AND-LUT array. PLAs are suitable for the implementation of high fan-in logic circuits, while LUTs are used to implement low fan-in logic circuits. As a result, the proposed hybrid FPGA architecture (HFA) is more flexible to improve logic density. Experiments based on MCNC benchmark circuits were performed in both the hybrid architecture and conventional LUT-based symmetrical FPGA architecture in term of area consumption. Preliminary results indicate that on average, the area is reduced by 46% using the new hybrid architecture.展开更多
Based on architecture analysis of island-style F PGA,area and delay models of LUT FPGA are proposed.The models are used to analyze the effect of LUT size on FPGA area and performance.Results show optimal LUT size obta...Based on architecture analysis of island-style F PGA,area and delay models of LUT FPGA are proposed.The models are used to analyze the effect of LUT size on FPGA area and performance.Results show optimal LUT size obtained by computation models is the same as that from experiments:a LUT size of 4 produces the best area results,and a LUT size of 5 provides the better performance.展开更多
基金Supported by the National Natural Science Foundation of China(41175037)
文摘In order to precisely retrieve the atmospheric CO2 , a retrieval method based on both near infrared (NIR) and thermal infrared (TIR) is established firstly. Then a look-up-table (LUT) based fast line-by-line radiative transfer model (RTM) was integrated into the retrieval procedure to accelerate radiative transfer calculations. The LUT stores gas absorption cross-sections as a function of temperature, pressure and wavenumber. It could greatly reduce calculating time in radiative transfer compared to direct line-by-line method. Then retrieval was simulated using NIR, TIR and both bands. The retrieved CO2 profiles suggest joint approach could reconstruct CO2 profile better than those using NIR or TIR alone. Joint retrieval using both bands simultaneously could provide better constrain to CO2 vertical distribution in the whole troposphere.
文摘A new hybrid FPGA architecture is proposed. The logic tile,which consists of a logic cluster and related connection boxes (CBs), can be configured as either programmable logic arrays (PLAs) or look-up tables (LUTs), This architecture can be classified as an AND-LUT array. PLAs are suitable for the implementation of high fan-in logic circuits, while LUTs are used to implement low fan-in logic circuits. As a result, the proposed hybrid FPGA architecture (HFA) is more flexible to improve logic density. Experiments based on MCNC benchmark circuits were performed in both the hybrid architecture and conventional LUT-based symmetrical FPGA architecture in term of area consumption. Preliminary results indicate that on average, the area is reduced by 46% using the new hybrid architecture.
文摘Based on architecture analysis of island-style F PGA,area and delay models of LUT FPGA are proposed.The models are used to analyze the effect of LUT size on FPGA area and performance.Results show optimal LUT size obtained by computation models is the same as that from experiments:a LUT size of 4 produces the best area results,and a LUT size of 5 provides the better performance.