A Study on Dual-Load-Zone Model of Overlying Strata and Evolution Law of Mining Stress

The changeable structure and movement law of overlying strata are the main contributor to the change of mining stress. Starting from the relevant theory of key stratum and particularly based on the theory of mine ground pressure and strata control, this research proposed a new solution to mining stress problems by establishing a dual-load-zone stratum structural model. Elastic foundation beam theory was used to solve the stress of overlying strata of the dual-load-zones with superposition method, which revised the traditional calculation method of mining stress. The abnormal increase of lead abutment pressure in the mining area was explained effectively, through which the evolution law of mining stress in the case of hard rock was obtained. The results indicate that mining stress experiences a drastic change within the range of 50 m ahead of the coal wall due to the collapse of main roof; under the influence of main key stratum and inferior key strata, the influence range of lead abutment pressure is extended up to approximately 120 m in the working face; this remarkable increase can be attributed to the excessive length of sagging zone. Results from both the dual-load-zone model experiment and field measurement demonstrate high consistency. The model can predict the influence range of abutment pressure effectively and thus guide the safety production of mining.     

祁东煤矿综采覆岩破坏特征

阐述了祁东煤矿地质采矿条件的特殊性,介绍了祁东煤矿综采覆岩破坏的实测结果,结合国内其他矿区覆岩破坏的一般规律及特点,对比分析了祁东煤矿综采中硬覆岩破坏的异常特征,指出了祁东煤矿综采覆岩破坏出现异常的主要原因。     

基于Leader-Follower的分群移动控制算法

分布式智能体群体移动控制中,简洁高效的多任务分群和群体移动是实现复杂群体运动控制的基础.群体运动会受到各节点运动不统一的影响而产生震荡和波动,使群体的移动距离增加,降低了群体移动效率.受"阻尼减震"的启发,本文对领导者最大速度进行限制,同时调节合力组成比例,对节点间无序力进行弱化,减小无序力对群体移动的负面影响,突出移...     

筛分法和激光粒度法联合测定陆源碎屑岩粒度

用筛分法和激光粒度法联合测定陆源碎屑岩粒度,对激光粒度法的分析数据进行了校正,以保证两种方法的分析数据配套衔接.通过对比不同地质年代沉积岩的岩心校正前后概率累积频率曲线,校正后的曲线能更好地表征碎屑岩粒度的分布.对影响马尔文Mastersizer 2000激光粒度仪背景测量的进样器搅拌转速A、泵速B、超声强度C三个因子...     

浮纹织机针综的智能控制系统

在普通1515A型多梭箱织机上附加浮纹装置（针综开口、暂停、横动、变换机构等）织造浮纹织物,依靠织机中凸轮齿轮花型控制其在地布中运动距离是传统的方法。本文用PLC和交流伺服系统组成绝对位置控制系统来控制针综横向运动的精确距离,智能化控制系统具有手动、自动控制、花样数据设置和修改、掉电保护等人机对话功能。     

基于车载环境的交通目标跟踪

针对车载环境下小目标难以识别和相机动态移动造成的目标跟踪精度下降问题, 提出一种基于改进YOLOv5与ByteTrack的交通目标跟踪方法. 首先, 引入Transformer与加权特征金字塔(BiFPN)结构的思想重构YOLOv5检测网络, 有效捕获了特征的全局依赖关系, 缓解了深层卷积小目标信息丢失问题, 改善了车载环境下的目标检测性能. 此后, 以ByteTrack为基础提出了添加相机移动补偿的CMC-ByteTrack跟踪方法, 更精准地描述了视频前后帧的数据关联关系, 提高了相机大幅位移时的跟踪精度. 实验结果表明, 改进YOLOv5的平均检测精度(mAP)达到了82.2%, 相比原算法提高了3.9%, 与CMC-ByteTrack结合后的跟踪准确性(MOTA)相比改进前的跟踪方法提高了2.8%.     

垂直运动PMLSM电磁力角控制器仿真研究

本文通过对垂直运动永磁直线同步电机力角特性的分析,得出电磁力角控制策略,并设计出了电磁力角控制器。仿真结果表明,该控制方法提高了垂直运动永磁直线同步电动机运行的稳定性、可靠性和电机的运行效率,并可有效预防垂直运动永磁直线同步电动机的失步问题。     

模拟注视眼动的多聚焦彩色图像融合

多聚焦图像存在聚焦和离焦区。通常聚焦区吸引人的注意力,具有突出的视觉显著性。提出一种模拟人类视觉机制的彩色图像融合方法。利用超复数傅里叶变换改进传统显著性检测算法,直接检测彩色图像显著度;模拟人类视觉的注视眼动机制对图像尺度稍微扰动,并对不同尺度下获得的图像显著度进行累加;选择累计显著度最大的源图像像素构建融合图像,并采用颜色相似性准则处理边界带像素。相关仿真实验表明,超复数傅里叶变换充分利用了源图像的颜色信息,累加显著度能提高峰值信噪比并减少均方根误差。实验结果表明该方法可得到超过36 dB的峰值信噪比和小于个位数的均方误差,在图像融合中可得到相对好的主观视觉效果。     

Assistant force compensation for hand movement of patients by using exogenous signals and/or neurophysiological signals

Because functional diseases of the brain can cause disabilities related to human movement control, a compensation method was developed for improving the performance of hand movements. The compensation for human hand movements can be carried out by adding an assistant force that is generated from artificial equipment attached to a human arm. From the experiment on visual target tracking, it was found that the tracking trajectory was adequately represented by a dynamic model of the motion of an articulated industrial robot arm, and the different abilities for movement control among healthy people and patients were classified by different model parameters as position loop gain, velocity loop gain, and response delay. Dynamic force compensation was approached by considering the different control features of the patients. The effectiveness of the proposed compensation method was verified in a simulation study on an actual industrial robot arm. A human-machine interface, e.g., a brain-computer interface (BCI), for realizing the control of artificial equipment to compensate for human hand movements is also presented and discussed.     

高压开关运动系统等效质量的计算

提出用“基本形块”分割法来计算形状复杂构件的转动惯量,这种方法易于写出通用算式,并便于用作图法简化计算.在速度比方面,介绍了作图解法和适于计算机使用的算式.