Earthshaker: A mobile rescue robot for emergencies and disasters through teleoperation and autonomous navigation

To deal with emergencies and disasters without rescue workers being exposed to dangerous environments, this paper presents a mobile rescue robot, Earthshaker. As a combination of a tracked chassis and a six-degree-of-freedom robotic arm, as well as miscellaneous sensors and controllers, Earthshaker is capable of traversing diverse terrains and fulfilling dexterous manipulation. Specifically, Earthshaker has a unique swing arm—dozer blade structure that can help clear up cumbersome obstacles and stabilize the robot on stairs, a multimodal teleoperation system that can adapt to different transmission conditions, a depth camera-aided robotic arm and gripper that can realize semiautonomous manipulation and a LiDAR aided base that can achieve autonomous navigation in unknown areas. It was these special systems that supported Earthshaker to win the first Advanced Technology & Engineering Challenge (A-TEC) championships, standing out of 40 robots from the world and showing the efficacy of system integration and the advanced control philosophy behind it.     

变压器绕组短路故障多特征融合诊断

绕组匝间短路是变压器最常见的初期故障类型之一.为了提高轻度故障的诊断准确率,考虑绕组短路电流、绕组温度、电流密度和磁通偏移特征,提出了变压器绕组短路故障的多特征融合诊断方法.首先建立了变压器绕组短路的COMSOL空间模型,将仿真结果和理论计算结果进行对比,证明空间模型的正确性.然后,对变压器轻度故障时进行了故障模拟和故障特征分析,提取其电流特征参量、温度特征参量、电流密度偏移率和磁通偏移率作为故障特征.采用BP网络进行故障识别.变压器的工程诊断实例验证了本文方法的有效性.     

地空数据传输系统中单载波频域预均衡技术

在频率选择性瑞利慢衰落信道条件下,提出了一种适用于地空传输系统上行链路的单载波频域预均衡方法。在此基础上设计了预均衡系统模型,地面端将下行链路中的导频信号与本地导频信号对比进行信道状态估计,利用获得的信道状态信息对上行链路信号进行预均衡处理,然后在机载接收端对上行链路信号进行再均衡。基于迫零准则和最小均方误差准则,分析了该方法的信号处理流程,计算得到预均衡系数。通过仿真实验,对比分析了不同均衡方案的误码性能,结果表明:单独在地面发送端进行预均衡,会出现误码率平台效应;而预均衡之后在机载接收端进行再均衡的方法,在误码率为10-5的情况下,与采用线性均衡结构的传统单载波频域均衡方法相比有2~3dB的性能增益。     

H_2O_2 氧化玉米淀粉胶性能研究

在引入预糊化剂的条件下,利用Ｈ２Ｏ２对玉米淀粉进行氧化,通过正交设计选择最佳氧化条件,确定对氧化淀粉进一步改性所用试剂的量,以降低淀粉胶的粘度,提高其流动性和初粘强度。实验所得产品淀粉胶与目前普遍使用的白乳胶相比,性能相近。     

组合合成阵的不可约性

本文讨论了布尔矩阵的组合合成的基本性质,用图论方法找出了２级组合合成阵为不可约的一些充分条件。     

机器人多指协调操作中抓取力的实时控制

提出了一个通用的抓取力实时控制算法．推广了抓取力的定义,探讨了抓取力存在性．定义了最优抓取力,给出了计算最优抓取力的具体算法．其核心是把抓取力的大小与方向分开处理,在抓取规划阶段确定抓取力的方向,在任务操作时仅调整抓取力的大小,而方向保持不变．该算法能很好地满足协调操作中力控制的实时性要求．仿真结果显示了其优越性．     

Molecular cloning and nucleotide sequence of classical swine fever virus strain Shimen

According to the previously published CSFV sequences, 18 paris of partially overlapping primers which span the entire genome of CSFV strain Shimen were designed and synthesized. Each cDNA fragment of strain Shimen was amplified by RT-PCR method from the anticoagulant blood of strain Shimen infected pig. The PCR fragments were cloned into pGEM-T vector respectively and sequenced. The results show that we have obtained the nucleotide sequence of strain Shimen. The viral RNA consists of 12 297 nucleotides including noncoding regions of 373 and 227 bases at the 5′ and 3′ end, respectively, and a single large open reading frame spanning 11 697 nucleotides in the middle, which encodes an amino acid sequence of 3 989 residues with a calculated molecular weight of 437.6×10³. The precisely sequencing of 5′ and 3′ termini is undertaking. Supported by the National Pandeng Project Huang Qianhua: born in 1968. Graduate student     

化学活性表面的分形研究

利用近十年来兴起的分形几何学,对固体表面进行了研究,指出固体表面的粗糙程度及不规则性可以用分形维数给予很好的定量描述,并给出了测定化学活性固体表面分形维数的方法。     

关于碳化硅作为超低碳钢连铸结晶器保护渣熔速调节剂的研究

本文研究了碳化硅（SiC）作为保护渣熔速调节剂的特性及作用机理,研究表明,以SiC替代炭质材料可大大降低保护渣对超低碳钢连铸坯的增碳和渗碳量。     

关于傅科摆相对运动轨迹的讨论

根据傅科摆确定的起始条件,正确导出其轨迹方程,并用计算机画出其相对运动轨迹曲线。同时推证得摆锤在最大幅角位置时,其相对速度为零这一重要特征。