荧光磁粉探伤裂纹智能识别图像处理研究

磁粉探伤的发展趋势是自动化、智能化,而工件表面状况、真伪裂纹、工况条件等使得现有的检测识别方法难以满足工件表面裂纹缺陷自动检测识别的需要。在分析工件表面荧光磁粉图像特征及裂纹缺陷特征的基础上,研究表征裂纹邻域像素空间相关度的二维直方图分布,提出基于多重分块极值的图像边缘检测算法。根据裂纹邻域像素空间相关度参数,以及裂纹缺陷的长宽比、圆形度等特征,设计了基于Fisher线性判别方法的工件裂纹识别算法。以此为基础的荧光磁粉探伤工件裂纹缺陷自动检测识别技术,应用于列车轮轴检测线实时检测,裂纹缺陷的有效检出率达99%。     

Incorporating the extended theory of planned behavior in a school travel mode choice model: a case study of Shaoxing,China

Travel to and from school can have social, economic, and environmental implications for students and their parents. Therefore, understanding school travel mode choice behavior is essential to find policy-oriented approaches to optimizing school travel mode share. Recent research suggests that psychological factors of parents play a significant role in school travel mode choice behavior and the Multiple Indicators and Multiple Causes (MIMIC) model has been used to test the effect of psychological constructs on mode choice behavior. However, little research has used a systematic framework of behavioral theory to organize these psychological factors and investigate their internal relationships. This paper proposes an extended theory of planned behavior (ETPB) to delve into the psychological factors caused by the effects of adults’ cognition and behavioral habits and explores the factors’ relationship paradigm. A theoretical framework of travel mode choice behavior for students in China is constructed. We established the MIMIC model that accommodates latent variables from ETPB. We found that not all the psychological latent variables have significant effects on school travel mode choice behavior, but habit can play an essential role. The results provide theoretical support for demand policies for school travel.     

通信对抗效能的计算机仿真浅析

通过介绍通信对抗效能计算机分析仿真原理、蒙特卡洛法、数字传输系统的计算机仿真原理、系统结构、仿真执行器机制、模型库开发技术,给出具体仿真模型.     

大吨位球型钢支座安装技术

大胜关长江大桥主桥钢梁支座自重大、尺寸大,安装质量要求高。以钢支座安装为工程实例,对6～8号墩和0～5号墩钢梁支座安装方法进行介绍,重点阐述了保证支座安装质量的关键技术措施。     

三维变速拖曳数学模型

分析了水下拖曳系统中拖船机动转弯、变速直航时，水下拖索的受力和运动情况以及水下拖索与拖曳器的相互影响关系，并建立了变速拖曳时，水下拖索的三维数学模型。最后的算例表明该模型具有一定的工程实际价值。     

多巴胺抑制大鼠背角伤害性神经元初步观察

本实验用玻璃微电极细胞外记录方法,观察了脊髓局部应用DA对清醒大鼠背角伤害性神经元电活动的影响。发现DA对背角伤害性神经元的自发放电和RHS、TES诱发反应均有抑制作用;DA对TES诱发反应的抑制主要表现为后串放电脉冲数的减少,但在有些神经元还伴有后串放电的潜伏期延长、时程缩短或频率下降;DA的作用可被静脉注射DA能受体拮抗剂氟哌啶所翻转。本文在国内首次证实,DA对大鼠背角伤害性神经元具有抑制作用。     

桥梁结构现有技术状况的模糊综合评判

传统的桥梁结构技术状况评价主要依靠结构的强度、稳定性、刚度及其裂缝等方面的信息,运用调查、检测和验算相结合的手段,对现有桥梁的承载能力及使用条件做综合评定。该文借鉴模糊数学的原理,通过建立综合评判模型,确定隶属函数和权重,用模糊综合评判的方法来对桥梁做出一个比较客观的评价,并通过袂花江大桥的例子来分析说明。     

城市客车车内噪声振动实测分析

噪声振动测试是解决车辆噪声问题的首要环节,对城市客车车内噪声和车体振动进行了测试,分析了城市客车车内噪声振动分布情况、噪声振动频谱特征.分析结果表明,城市客车噪声与发动机的振动有直接关系,噪声分布的主要频率为63 Hz～1 kHz.     

Intelligent drug delivery system using UML diagrams analysis

A novel intelligent drug delivery system potential for the more effective therapy of the diabeticswas proposed, and the composition of system was analyzed. Based on the design of micro-electro-mechanicalsystems (MEMS), an iterative modeling process was introduced. Unified modeling language (UML) was em-ployed to describe the function requirement, and different diagrams were built up to explore the static model,the dynamic model and the employment model. The mapping analysis of different diagrams can simply verifythe consistency and completeness of the system model.     

跨海桥梁基础冰荷载计算探讨

总结了海冰与桥梁基础的作用形式,分析了几种冰荷载计算公式的适用性,提出了跨海桥梁基础冰荷载计算需要考虑的因素,最后结合某跨海桥梁基础给出了冰荷载计算算例。