Internal short circuit detection method for battery pack based on circuit topology

Internal short circuit(ISCr) is one of the major obstacles to the improvement of the battery safety. The ISCr may lead to the battery thermal runaway and is hard to be detected in the early stage. In this work, a new ISCr detection method based on the symmetrical loop circuit topology(SLCT) is introduced. The SLCT ensures that every battery has the same priority in the circuit and every battery will contribute the same amount of short-circuit current to the ISCr once the ISCr happens. The ISCr battery could be identified by the combination of the ratio of the short-circuit currents and the sign of the short-circuit currents. The recursive least square method is adopted for the real-time application and the optimized ammeters allocation is derived from the mathematic deduction. The battery pack based on the individual DP(dual polarization) battery model is established to verify the ISCr detection method. The 1–1000 Ω s ISCr(the early stage ISCr) can be effectively detected within 1–125 s. The SLCT provides the possibility of new battery pack designs and new battery management methods. The proposed ISCr detection method shows excellent effectiveness and efficiency on the identification of the ISCr battery in the early stage.     

改扩建工程工艺管线碰头口焊接管理

通过扬子石油化工公司85万t/a芳烃改扩建工程工艺管线碰头口焊接质量管理的成功经验,阐述如何保证改扩建工程工艺管线碰头口焊缝的焊接质量,为公司以后改扩建工程实施工艺管线碰头口焊接质量管理积累了经验.     

景观作品应经得起“取景”

大家也许都有这样的体会。有些景观建成后粗看很是“热闹”，但真要拿起相机取景时，往往很难找到一幅满意的“构图”，或是构图失去均衡；或是画面缺少必要的主体，或是色彩层次不够，或是——其实一个真正好的景观设计作品建成后除了应经得起公众“看”以外，还应经得起摄影师的“取景”，既我们通常所说的“要有好的景点”。     

一种基于DSC无刷直流电机无传感器新控制方法

介绍了一种基于DSC（数字信号控制器）无刷直流电机无传感器新控制方法，包括工作原理和系统组成。     

Thermal and elemental analysis of the combustion chamber deposits in a large-scale two-stroke marine diesel engine

It is of significance to understand the chemical content of carbon deposits in the large-scale two-stroke(LSTS) marine diesel engine because of adverse effect on the engine performance, oil consumption and emissions. In this work, two different combustion chamber deposits in an LSTS marine diesel engine were studied using thermogravimetry analysis(TGA), elemental analysis(EA) and synchrotron X-ray fluorescence(SXRF). One was on the piston top and the other on the piston land, termed PTCD and PLCD, respectively. For the PTCD sample, the 97% residue in the TGA and 1.4% carbon content in the EA indicated the main compositions of PTCD were metal salts or oxides and ashes, significantly different from the previous findings of the highest carbon content in deposits from the small four stroke engines. The different chemical content between PTCD and PLCD implied higher thermal load in the LSTS marine diesel engine led to a nearly complete thermal decomposition of PTCD. The higher calcium content in PTCD and PLCD indicated the additives of cylinder oil should be the main source of metal content of PTCD and PLCD. Calcium distribution in the SXRF results was indicative of the potential layered structure in PTCD and PLCD. In addition, the appearance of iron on the surface against the piston in PTCD and PLCD indicated iron oxides formation between carbon deposit and piston materials.     

安塞油田南部侏罗系延8～延9储层特征及控制因素研究

安塞油田南部侏罗系延安组延8～延9储层是一套以长石砂岩、岩屑长石砂岩、岩屑石英砂岩和长石石英砂岩为主的陆源碎屑沉积,为早成岩期的产物,成分成熟度和结构成熟度均较低,属三角洲前缘亚相范畴.孔隙类型包括原生粒间孔和次生孔隙,后者以粒间溶孔为主.通过成岩分析,指出沉积物源及古地理环境控制着储层性质,成岩作用使储层物性进一步变差,而溶解作用改善了储层性能.     

基于改进小生境遗传算法的微波/光混合链路中继卫星资源调度方法

针对微波/光混合链路中继卫星系统多资源约束 下的多目标综合调度问题,分析了微波与激光混 合链路的主要特点和影响因素,建立了混合链路资源调度多目标约束规划模型;将小生境技 术引入遗传 算法,并设计了基于精英保留的选择机制和自适应的交叉、变异算子,提出了一种改进的小 生境遗传算 法对模型进行求解。所提算法可有效避免遗传算法局部优化能力差及容易陷入局部最优等缺 陷,同时能够 防止最优解的丢失,解决了混合链路多资源约束下的多目标综合调度问题。仿真结果表明 ,相对与传统 的遗传算法,本文算法在保持种群多样性和求解全局最优解方面具有优势,有效解决微波/ 激光混合链路中继卫星系统的多目标综合调度问题。     

Study on the hardening mechanism of cement asphalt binder

The hydration and hardening mechanism of cement asphalt binder(CAB) was studied.The early hydration process,hydration products and paste microstructure of CAB made by Portland cement and anionic asphalt emulsion were investigated by calorimetry,X-ray diffraction,and environmental scanning electron microscopy.The early hydration process of CAB can be characterized as 5 stages similar to those of Portland cement.There is no chemical reaction detected between cement and asphalt,hence no new hydration products ...     

车身控制CAN总线系统开发

本文以长安公司SC6350车型为实验对象,依据CAN2.0B标准协议设计了车身CAN总线应用层协议,定义了报文的标识系统和数据域报文编码方式。同时,根据车身电器的特点,制定了长安SC6350车身CAN报文具体格式,设计了3类控制报文服务过程,并通过了CAN/LIN测试平台软件的测试,实现了车身电器的CAN总线控制系统。     

A new kind of magnetic targeting induction heating drug carrier and its physical and biological properties

Nano-carbon and iron composite―carbon-coated iron nanoparticles (CCINs) produced by carbon arc method can be used as a new kind of magnetic targeting induction heating drug carrier for cancer therapy. The structure and morphology of CCINs are studied by X-ray diffraction (XRD) and transmission electron microscope (TEM). Mossbauer spectra of these nanoparticles show that they contain only iron and carbon, without ferric carbide and ferric oxide. CCINs can be used as the magnetic drug carrier, with the effect...