Research on wind turbine blade damage based on pre-stressed FBG strain sensors

One of the essential parts of a wind power generator that captures wind energy is the wind turbine blade. The safety of the blades rapidly declines as a wind turbine''s operating period grows. For real-time monitoring, a chip-type pre-stressed fiber Bragg grating (FBG) strain sensor was fabricated. The sensor''s structure was improved using simulation analysis along with optimization. It was discovered through calibration trials that the pre-stressing method expanded the sensor''s range of measurement, guaranteed overall linearity, and prevented the potential hysteresis phenomena during compression. The sensor''s final sensitivity was calculated to be 1.970 pm/με, and its linear fitting coefficient was 0.999. Finally, the sensor was used to monitor the wind turbine blades and the strain change curve of the root of a normally functioning blade is found to be a sine curve, which provides a certain reference value for judging whether the blade is damaged in the future.     

基于爬虫的XSS漏洞检测工具设计与实现

通过对XSS漏洞的研究,剖析其产生、利用的方式,在此基础上针对XSS漏洞的检测机制进行进一步的分析和完善。结合网络爬虫的技术,研究设计并实现了一款XSS漏洞的检测工具（XSS-Scan）,并与当前比较流行的一些软件做了分析比较,证明利用该工具可以对Web网站进行安全审计,检测其是否存在XSS漏洞。     

碳和磷对热轧带钢氧化铁皮起泡行为的影响

氧化铁皮的起泡行为发生在热轧过程,当铁皮发生起泡现象时,铁皮界面气体压力增加造成铁皮被顶起,在热轧轧制中起泡的铁皮被碾碎易于形成麻点和铁皮压入缺陷.通过热重分析手段和扫描电镜微观观察研究了超低碳钢、超低碳含磷钢、低碳钢、中碳钢在加热过程中铁皮的起泡行为,重点探讨了磷和碳元素对铁皮起泡行为的影响.研究表明,在980℃附近磷元素形成Fe3(PO4)2,此相高温下易于熔融气化造成铁皮起泡;在1050℃以上的高温区间,碳元素活性增高,随着铁皮生长界面碳元素的富集氧化,形成CO和CO2对铁皮起泡影响明显,高温试样铁皮气孔和裂纹密集.     

Status of eddy current testing in India

The status of eddy current testing (ECT) in India from various considerations is discussed in this paper. The points considered are: (i) the industrial back ground of India which has motivated the development and use of ECT; (ii) ECT in quality assurance; (iii) ECT in codes and standards as practised in India; (iv) capabilities of Indian-made ECT equipment; (v) manpower training in ECT in India; and (vi) research and development in ECT in India, including applications such as nuclear cladding tubes, surface probes, measurement of level of liquid metals, composites, and inservice inspection. Future trends expected to develop from the present status are also explained.     

中风化花岗岩中嵌岩桩承载性能原位试验与极限承载力预测

为深入探究中风化花岗岩中嵌岩桩的竖向抗压承载特性,对12根嵌岩桩进行了单桩竖向抗压静载原位试验与ABAQUS有限元数值模拟,通过多种方法对嵌岩单桩极限承载力进行评价,明确中风化花岗岩中嵌岩桩竖向抗压承载性状。研究表明:12根中风化花岗岩中嵌岩桩并非表现出完全端承桩,而是呈摩擦型桩或摩擦端承桩的性状;中风化花岗岩地基中的嵌岩桩竖向抗压极限承载力较高,桩顶沉降小,满足工程对基础的承载要求;有限元模拟荷载-沉降曲线与实测荷载-沉降曲线走势吻合度较高,桩顶沉降误差较小;本试验条件下,桩端阻力占桩顶荷载的56.9%,桩侧摩阻力占比为43.1%,桩侧摩阻力在荷载传递过程中发挥较充分;有限元模拟得到的单桩极限承载力与指数函数模型的预测结果较为吻合,可用于嵌岩桩单桩竖向抗压极限承载力的预测,以及嵌岩桩承载性状和荷载传递规律的分析。     

Wear of wheel-rail surfaces

The interactions between the tribological stress parameters and the measurable wear quantities during rolling with slip are examined with the help of experimental results already published and the results of some new investigations by the authors of this paper.It is from these that the following model for wear behaviour is derived.

• 1.(1) The wear quantities (wear volume and mass loss due to wear) are first of all proportional to the frictional work.
• 2.(2) The factor of proportionality between frictional work and wear volume depends on (a) the structure of the tribological system (material pairing and environment) and (b) the temperature of the contacting surfaces. This temperature is a function of the stress collective, the influence of which may be approximated as the relation of frictional power to contact area, the surface temperature thus governing the transitions between mild and severe wear.

     

Growth mechanism for zinc coatings deposited by vacuum thermal evaporation

The vacuum thermal evaporation technique was used to simultaneously deposit zinc coatings onto interstitial free steel plates and single-crystal silicon wafers ...     

东濮凹陷砂岩储集层物性参数关系研究及随钻应用方法

储集层的物性参数是评价储集层的重要基础数据,对储集层评价的准确程度有较大影响,文章统计分析结果表明砂岩储集层岩石密度与储集层主要物性参数之间有良好的相关性。以区域统计规律为基础,建立了东濮凹陷砂岩储集层体积密度与孔隙度和渗透率的关系方程。介绍了录井施工现场应用岩屑样品体积置换法、泥岩密度计法两种常规检测方法,能较准确的获取砂岩储集层的体积密度,反演计算孔隙度和渗透率数据,合理评价储集层物性参数,为准确评价储集层提供了可信度高的重要基础数据,从而弥补了录井现场物性参数获取不足的缺陷,在随钻评价油气储集层过程中有一定的实用价值。     

高Ti,Nb析出强化高强钢接头强度及焊接热影响区软化行为分析

采用混合气体（80％Ar＋20％CO2）保护焊对高Ti,Nb析出强化高强钢进行了焊接强度试验研究．结果表明,随着焊接热输入增大,接头强度有降低趋势．焊接热影响区较母材硬度降低,存在软化行为．粗晶区晶粒长大及10nm以下（Ti,Nb,Mo）（C,N）第二相粒子的溶解造成强化效果降低．未溶的（Ti,Nb,Mo）（C,N）第二相粒子固定了C,Mo元素,降低过冷奥氏体的稳定性,不能得到硬度较高的板条状马氏体或贝氏体,而形成硬度较低的粒状贝氏体．第二相强化效果的降低不能通过组织强化有效弥补,从而造成粗晶区软化．在细晶区热循环作用下,10nm以下第二相粒子粗化,使得偏离其临界强化尺寸,析出强化效果降低,造成细晶区软化．     

基于Fuzzing的蓝牙OBEX漏洞挖掘技术

Fuzzing是一种自动化的漏洞挖掘技术。该文在分析OBEX 协议的基础上,利用Fuzzing技术,设计并实现了蓝牙OBEX协议的Fuzzer工具——OBEX-Fuzzer,并且利用该工具对OBEX协议在Nokia N73和SMH-BT555蓝牙适配器上的实现进行了漏洞测试,发现存在多个安全漏洞,实践结果表明了研究思路的正确性以及利用OBEX-Fuzzer工具进行安全漏洞测试的高效性。