Transcendental functions are important functions in various high performance computing applications.Because these functions are time-consuming and the vector units on modern processors become wider and more scalable,t...Transcendental functions are important functions in various high performance computing applications.Because these functions are time-consuming and the vector units on modern processors become wider and more scalable,there is an increasing demand for developing and using vector transcendental functions in such performance-hungry applications.However,the performance of vector transcendental functions as well as their accuracy remain largely unexplored.To address this issue,we perform a comprehensive evaluation of two Single Instruction Multiple Data(SIMD)intrinsics based vector math libraries on two ARMv8 compatible processors.We first design dedicated microbenchmarks that help us understand the performance behavior of vector transcendental functions.Then,we propose a piecewise,quantitative evaluation method with a set of meaningful metrics to quantify their performance and accuracy.By analyzing the experimental results,we find that vector transcendental functions achieve good performance speedups thanks to the vectorization and algorithm optimization.Moreover,vector math libraries can replace scalar math libraries in many cases because of improved performance and satisfactory accuracy.Despite this,the implementations of vector math libraries are still immature,which means further optimization is needed,and our evaluation reveals feasible optimization solutions for future vector math libraries.展开更多
High performance X8R dielectric ceramics were prepared by dopingBi2O3 to BaTiO3-based ceramics.The effect of small amounts（≤1.2 mol%） ofBi2O3 additive on the microstructure and dielectric properties of BaTiO3-based...High performance X8R dielectric ceramics were prepared by dopingBi2O3 to BaTiO3-based ceramics.The effect of small amounts（≤1.2 mol%） ofBi2O3 additive on the microstructure and dielectric properties of BaTiO3-based ceramics have been investigated.The Bi2O3 ,acting as a sintering additive,can effectively lower the sintering temperature of BaTiO3-based ceramics from 1300 to 1130 °C.The bulk density of BaTiO3-based ceramics increased and reached the maximum value with increasingBi2O3 content.The dielectric constant increased with increasingBi2O3 until it reached the maximum value with 0.8 mol%Bi2O3 additive,and the dielectric loss decreased with increasingBi2O3 content.Optimal dielectric properties of ε=2470,tanδ=0.011 and △ε/ε 25 ≤±9%（-55-150 °C） were obtained for the BaTiO3-based ceramics doped with 0.8 mol%Bi2O3 sintered at 1130 °C for 6 h.展开更多
Vehicle tracking plays a crucial role in intelligent transportation, autonomous driving, and video surveillance. However, challenges such as occlusion, multi-target interference, and nonlinear motion in dynamic scenar...Vehicle tracking plays a crucial role in intelligent transportation, autonomous driving, and video surveillance. However, challenges such as occlusion, multi-target interference, and nonlinear motion in dynamic scenarios make tracking accuracy and stability a focus of ongoing research. This paper proposes an integrated method combining YOLOv8 object detection with adaptive Kalman filtering. The approach employs a support vector machine (SVM) to dynamically select the optimal filter (including standard Kalman filter, extended Kalman filter, and unscented Kalman filter), enhancing the system’s adaptability to different motion patterns. Additionally, an error feedback mechanism is incorporated to dynamically adjust filter parameters, further improving responsiveness to sudden events. Experimental results on the KITTI and UA-DETRAC datasets demonstrate that the proposed method significantly improves detection accuracy (mAP@0.5 increased by approximately 3%), tracking accuracy (MOTA improved by 5%), and system robustness, providing an efficient solution for vehicle tracking in complex environments.展开更多
A new Pb（II）-based coordination polymer, [Pb（L）]n （1）, was hydrothermally synthesized and its structure was determined by single-crystal X-ray diffraction （H2L = octane- 1,8-dicarboxylic acid）. Compound 1 crys...A new Pb（II）-based coordination polymer, [Pb（L）]n （1）, was hydrothermally synthesized and its structure was determined by single-crystal X-ray diffraction （H2L = octane- 1,8-dicarboxylic acid）. Compound 1 crystallizes in orthorhombic, space group Pnma with a = 32.061（4）, b = 7.2597（8）, c = 4.8084（5） A, V= 1119.2（2） A3, Z = 4, C10H1604Pb, Mr = 407.42, Dc = 2.418 g/cm3, F（000） = 760, μ（MoKa） = 15.066 mm-1, R = 0.0270 and wR = 0.0666. In 1, each Pb（II） cation is coordinated by six carboxylate oxygen atoms from four L2- anions. Each L2- anion bridges three Pb（ll） atoms in a μ3：η2：η1：η1 mode to form a 3D framework. The structure of 1 was characterized by IR spectrum and thermogravimetric analysis. Moreover, solid state luminescent property of 1 was also investigated.展开更多
M2SisN8：Eu2＋-based （M=Ca, Sr, Ba） red-emitting phosphors are fabricated at relatively low temperature （1200℃） and atmos- pheric pressure using a simple solid-state reaction process. Several processing parameter...M2SisN8：Eu2＋-based （M=Ca, Sr, Ba） red-emitting phosphors are fabricated at relatively low temperature （1200℃） and atmos- pheric pressure using a simple solid-state reaction process. Several processing parameters are systematically investigated to optimize the phosphors structural characterization and photoluminescence performance, including the amount of europium and the properties of the precursor materials. The as-prepared M2SisNs：Eu2＋-based （M=Ca, Sr, Ba） phosphors are orange in color and are intensively emitted in the red region of 580-670 nm under 465 nm excitation.展开更多
基金supported by the National Key Research and Development Program of China under Grant No.2020YFA0709803the National Natural Science Foundation of China under Grant Nos.61902407 and 61802416.
文摘Transcendental functions are important functions in various high performance computing applications.Because these functions are time-consuming and the vector units on modern processors become wider and more scalable,there is an increasing demand for developing and using vector transcendental functions in such performance-hungry applications.However,the performance of vector transcendental functions as well as their accuracy remain largely unexplored.To address this issue,we perform a comprehensive evaluation of two Single Instruction Multiple Data(SIMD)intrinsics based vector math libraries on two ARMv8 compatible processors.We first design dedicated microbenchmarks that help us understand the performance behavior of vector transcendental functions.Then,we propose a piecewise,quantitative evaluation method with a set of meaningful metrics to quantify their performance and accuracy.By analyzing the experimental results,we find that vector transcendental functions achieve good performance speedups thanks to the vectorization and algorithm optimization.Moreover,vector math libraries can replace scalar math libraries in many cases because of improved performance and satisfactory accuracy.Despite this,the implementations of vector math libraries are still immature,which means further optimization is needed,and our evaluation reveals feasible optimization solutions for future vector math libraries.
基金supported by the Tianjin Natural Science Foundation, China (Grant No. 06YFJMJC01000)
文摘High performance X8R dielectric ceramics were prepared by dopingBi2O3 to BaTiO3-based ceramics.The effect of small amounts（≤1.2 mol%） ofBi2O3 additive on the microstructure and dielectric properties of BaTiO3-based ceramics have been investigated.The Bi2O3 ,acting as a sintering additive,can effectively lower the sintering temperature of BaTiO3-based ceramics from 1300 to 1130 °C.The bulk density of BaTiO3-based ceramics increased and reached the maximum value with increasingBi2O3 content.The dielectric constant increased with increasingBi2O3 until it reached the maximum value with 0.8 mol%Bi2O3 additive,and the dielectric loss decreased with increasingBi2O3 content.Optimal dielectric properties of ε=2470,tanδ=0.011 and △ε/ε 25 ≤±9%（-55-150 °C） were obtained for the BaTiO3-based ceramics doped with 0.8 mol%Bi2O3 sintered at 1130 °C for 6 h.
文摘Vehicle tracking plays a crucial role in intelligent transportation, autonomous driving, and video surveillance. However, challenges such as occlusion, multi-target interference, and nonlinear motion in dynamic scenarios make tracking accuracy and stability a focus of ongoing research. This paper proposes an integrated method combining YOLOv8 object detection with adaptive Kalman filtering. The approach employs a support vector machine (SVM) to dynamically select the optimal filter (including standard Kalman filter, extended Kalman filter, and unscented Kalman filter), enhancing the system’s adaptability to different motion patterns. Additionally, an error feedback mechanism is incorporated to dynamically adjust filter parameters, further improving responsiveness to sudden events. Experimental results on the KITTI and UA-DETRAC datasets demonstrate that the proposed method significantly improves detection accuracy (mAP@0.5 increased by approximately 3%), tracking accuracy (MOTA improved by 5%), and system robustness, providing an efficient solution for vehicle tracking in complex environments.
基金Supported by the Institute Foundation of Siping City(No.2013036)
文摘A new Pb（II）-based coordination polymer, [Pb（L）]n （1）, was hydrothermally synthesized and its structure was determined by single-crystal X-ray diffraction （H2L = octane- 1,8-dicarboxylic acid）. Compound 1 crystallizes in orthorhombic, space group Pnma with a = 32.061（4）, b = 7.2597（8）, c = 4.8084（5） A, V= 1119.2（2） A3, Z = 4, C10H1604Pb, Mr = 407.42, Dc = 2.418 g/cm3, F（000） = 760, μ（MoKa） = 15.066 mm-1, R = 0.0270 and wR = 0.0666. In 1, each Pb（II） cation is coordinated by six carboxylate oxygen atoms from four L2- anions. Each L2- anion bridges three Pb（ll） atoms in a μ3：η2：η1：η1 mode to form a 3D framework. The structure of 1 was characterized by IR spectrum and thermogravimetric analysis. Moreover, solid state luminescent property of 1 was also investigated.
基金supported by New Century Excellent Talents of the University in China for the financial support(Grant No.NCET-04-0975)
文摘M2SisN8：Eu2＋-based （M=Ca, Sr, Ba） red-emitting phosphors are fabricated at relatively low temperature （1200℃） and atmos- pheric pressure using a simple solid-state reaction process. Several processing parameters are systematically investigated to optimize the phosphors structural characterization and photoluminescence performance, including the amount of europium and the properties of the precursor materials. The as-prepared M2SisNs：Eu2＋-based （M=Ca, Sr, Ba） phosphors are orange in color and are intensively emitted in the red region of 580-670 nm under 465 nm excitation.
