The rods that were shaped from nanocrystalline WC- 10.21 Co-0.42 VC/ Cr3 C2 （ wt% ） composite powders by using powder extrusion molding （PEM） were investigated. The nanocrystalline WC- 10.21 Co- 0. 42 VC/ Cr3 C2 ...The rods that were shaped from nanocrystalline WC- 10.21 Co-0.42 VC/ Cr3 C2 （ wt% ） composite powders by using powder extrusion molding （PEM） were investigated. The nanocrystalline WC- 10.21 Co- 0. 42 VC/ Cr3 C2 （ wt% ） composite powders were prepared by the spray thermal decomposition-continuous reduction and carburization technology. In order to improve the properties of rods shaped by using powder extrusion molding, the cold isostatic pressing （CIP） technology was used before or after debinding. Specimens were siutered by vacuum siutering and hot isostatic pressing （HIP）. The density, Rockwell A hardness, magnetic coercivity , and magnetic saturation induction of siutered specimen were measured. The microstructure of the green bodies and the siutered specimens was studied by scanning electron microscopy （SEM）. Results show that the rod formed by using powder extrusion molding after debinding and followed by cold isostatic pressing can be siutered to 99.5% density of composite cemented carbide rods with an average grain size of about 200- 300 nm, magnetic coercivity of 30.4 KA / m, Rockwell A hardness of 92.6 and magnetic saturation induction of 85% . Superfine WC- 10 Co cemented carbide rods with excellent properties were obtained.展开更多
在艺术与科技研究领域中,针对目前大部分现有公开数据集过于老旧而导致已有研究方法在实际GUI(Graphical User Interface)检测中因界面所特有的组件种类多样、背景复杂的情况,同时因高分辨率显示器使得部分组件更小更密集从而导致检测...在艺术与科技研究领域中,针对目前大部分现有公开数据集过于老旧而导致已有研究方法在实际GUI(Graphical User Interface)检测中因界面所特有的组件种类多样、背景复杂的情况,同时因高分辨率显示器使得部分组件更小更密集从而导致检测效率不高和检测精度瓶颈等问题,该文依托太原师范学院智能科技与艺术创新科研平台自行构建GUI数据集并基于RT-DETR模型进行改进提出EM-DETR,构建面向GUI组件检测任务的实时目标检测网络创新性优化策略。为突破低质量样本与计算效率的双重限制,创新构建了引入增强定位敏感区域的表达能力模块的EMViT轻量化骨干网络;与此同时,为改善最近邻插值法可能出现细节丢失、锯齿状边缘和图像失真等问题,引入DySample上采样算子;最后为了解决低质量样本回归难题,设计基于WIoUv3的动态梯度分配策略。本实验在太原师范学院智能科技与艺术创新科研平台提供的GUI数据集中验证了检测精度及效率平衡方面的有效性。实验结果表明,检测平均精度(mAP)达到了89.8%,相较于原始RT-DETR提升了9.53百分点,同时,EM-DETR在检测速度上也表现出色,在GUI组件检测这一细分场景下,首次将RT-DETR架构的精度提高到可落地水平,在保持可接受的实时性同时大大提高了检测正确率。现已将其应用到教育部产学合作协同育人公示企业山西赛迩教育科技有限公司中的产品研发环节,取得良好效果。展开更多
为实现交叉口时空资源的高效利用,对交叉口车道布局与信号控制协同优化问题进行了研究。首先,基于美国国家电气制造商协会(National Electric Manufacturers Association,NEMA)的双环标准相位,考虑饱和流量随车道数增加的递减效应,以信...为实现交叉口时空资源的高效利用,对交叉口车道布局与信号控制协同优化问题进行了研究。首先,基于美国国家电气制造商协会(National Electric Manufacturers Association,NEMA)的双环标准相位,考虑饱和流量随车道数增加的递减效应,以信号周期最小化为模型的目标,以车道布局、相位时长、饱和流量、交通流量、流量比、饱和度为模型的约束条件,建立了交叉口车道布局与信号控制方案协同优化的0-1混合整数线性规划(binary-mix-integer-linear-program,BMILP)模型。其次,使用分支定界法,快速得到模型的全局最优解。最后,选取南京市的北京东路-丹凤街交叉口,设定了3组不同的流量组合,对模型进行了实例验证。结果表明:模型可根据交叉口交通流量的分布特征,生成相应的车道布局和信号配时方案,无须预设特定的车道布局模式,且能灵活配置共享车道和右转相位;同时,对模型的最大可接受饱和度参数进行了敏感性分析,讨论了该参数和信号周期、相位饱和度等优化结果的关系。展开更多
基金Funded by Open Foundation of State Key Laboratory of AdvancedTechnologyfor Materials Synthesis and Processing, Wuhan Universi-ty of Technology, the Post PhD Science Foundation of China(2003034504) andthe Foundation of Wuhan University of Technol-ogy(2003XJJ202)
文摘The rods that were shaped from nanocrystalline WC- 10.21 Co-0.42 VC/ Cr3 C2 （ wt% ） composite powders by using powder extrusion molding （PEM） were investigated. The nanocrystalline WC- 10.21 Co- 0. 42 VC/ Cr3 C2 （ wt% ） composite powders were prepared by the spray thermal decomposition-continuous reduction and carburization technology. In order to improve the properties of rods shaped by using powder extrusion molding, the cold isostatic pressing （CIP） technology was used before or after debinding. Specimens were siutered by vacuum siutering and hot isostatic pressing （HIP）. The density, Rockwell A hardness, magnetic coercivity , and magnetic saturation induction of siutered specimen were measured. The microstructure of the green bodies and the siutered specimens was studied by scanning electron microscopy （SEM）. Results show that the rod formed by using powder extrusion molding after debinding and followed by cold isostatic pressing can be siutered to 99.5% density of composite cemented carbide rods with an average grain size of about 200- 300 nm, magnetic coercivity of 30.4 KA / m, Rockwell A hardness of 92.6 and magnetic saturation induction of 85% . Superfine WC- 10 Co cemented carbide rods with excellent properties were obtained.
文摘在艺术与科技研究领域中,针对目前大部分现有公开数据集过于老旧而导致已有研究方法在实际GUI(Graphical User Interface)检测中因界面所特有的组件种类多样、背景复杂的情况,同时因高分辨率显示器使得部分组件更小更密集从而导致检测效率不高和检测精度瓶颈等问题,该文依托太原师范学院智能科技与艺术创新科研平台自行构建GUI数据集并基于RT-DETR模型进行改进提出EM-DETR,构建面向GUI组件检测任务的实时目标检测网络创新性优化策略。为突破低质量样本与计算效率的双重限制,创新构建了引入增强定位敏感区域的表达能力模块的EMViT轻量化骨干网络;与此同时,为改善最近邻插值法可能出现细节丢失、锯齿状边缘和图像失真等问题,引入DySample上采样算子;最后为了解决低质量样本回归难题,设计基于WIoUv3的动态梯度分配策略。本实验在太原师范学院智能科技与艺术创新科研平台提供的GUI数据集中验证了检测精度及效率平衡方面的有效性。实验结果表明,检测平均精度(mAP)达到了89.8%,相较于原始RT-DETR提升了9.53百分点,同时,EM-DETR在检测速度上也表现出色,在GUI组件检测这一细分场景下,首次将RT-DETR架构的精度提高到可落地水平,在保持可接受的实时性同时大大提高了检测正确率。现已将其应用到教育部产学合作协同育人公示企业山西赛迩教育科技有限公司中的产品研发环节,取得良好效果。
文摘为实现交叉口时空资源的高效利用,对交叉口车道布局与信号控制协同优化问题进行了研究。首先,基于美国国家电气制造商协会(National Electric Manufacturers Association,NEMA)的双环标准相位,考虑饱和流量随车道数增加的递减效应,以信号周期最小化为模型的目标,以车道布局、相位时长、饱和流量、交通流量、流量比、饱和度为模型的约束条件,建立了交叉口车道布局与信号控制方案协同优化的0-1混合整数线性规划(binary-mix-integer-linear-program,BMILP)模型。其次,使用分支定界法,快速得到模型的全局最优解。最后,选取南京市的北京东路-丹凤街交叉口,设定了3组不同的流量组合,对模型进行了实例验证。结果表明:模型可根据交叉口交通流量的分布特征,生成相应的车道布局和信号配时方案,无须预设特定的车道布局模式,且能灵活配置共享车道和右转相位;同时,对模型的最大可接受饱和度参数进行了敏感性分析,讨论了该参数和信号周期、相位饱和度等优化结果的关系。
