基于Retinex模型和GTV的铁路货车铸件DR图像增强

铁路运输已成为我国最重要的运输方式之一,铁路货车部件(摇枕、侧架等)的铸造缺陷(气孔、裂纹等)可能造成交通事故。由于铁路铸件自身的不均匀性会导致原始DR图像灰度不均,不易捕捉缺陷细节,因此需要对原始DR图像进行图像增强等操作检测缺陷。基于Retinex模型,同时考虑目标的光照强度和材质信息,将图像分解为光照图和反射图。基于高斯全变分(GTV)的保护图像边缘滤波器可以平滑光照图像,并且可以移除光照图的纹理细节,因此缺陷等细节就暴露在反射图中。对于铁路货车铸件的缺陷识别问题,结合Retinex和GTV方法,提出一种改进的Retinex增强模型,利用GTV和基于纹理感知的加权项对Retinex分解过程中的光照图和反射图进行正则化。此外,用交替优化算法求解该模型。最后,将能够反映图像缺陷细节的反射图作为最终增强图像。此方法得到的图像不仅保留了图像的结构信息,还明显暴露了图像的缺陷细节。实验结果表明,与其他已有的模型相比,该模型增强缺陷效果显著,此外,该模型提高了DR图像的信息熵、平均梯度等量化指标。与原图相比,增强后图像的信息熵提高了8%以上,平均梯度至少提高为原来的6倍。此方法提高了DR图像检测缺陷的能力,可以应用于铁路货车铸件等无损检测领域。

河湖生态修复过程中的误区探讨与模式构建

文章针对河湖生态修复过程中普遍存在的误区及错误进行深入剖析,围绕“恢复河湖自身生境”的核心思路,提出了河湖生态修复的针对性措施和思考,并介绍了以“物化净化”、“生物多样性提高”、“引水调控”3类子修复模式为基础的6种生态修复模式及相应工程案例,为科学系统推进城市河湖生态修复提供一种新的思路。

Effect of Hot-Rolled Oxide Scale on Dry/ Wet Cyclic Corrosion Behavior of Q370qNH Steel in Simulated Industrial Atmosphere Environment

The corrosion behavior of Q370qNH steel in the presence and absence of hot-rolled oxide scale in simulated industrial atmospheric environment was studied by dry/wet cycle accelerated corrosion experiments.The experimental results show that the corrosion type of bare steel is uneven overall corrosion and large size pitting corrosion in small areas;that of oxide scale sample is local dissolution corrosion and small size pitting corrosion in large areas,and corrosion rate is much smaller than that of bare steel.The corrosion products of both steels are composed ofα-FeOOH,γ-FeOOH,Fe_(2)O_(3),and Fe_(3)O_(4),but the formation mechanism is different.The bare steel generatesα-FeOOH andγ-FeOOH through“acid regeneration cycle mechanism”;the oxide scale sample generates hydroxides mainly through the gradual dissolution of the oxide film,and then through“the acid regeneration cycle mechanism”.With the extension of corrosion time,the electrochemical stability of the sample with oxide scale increases,but the change of tafel curve of bare steel sample is not obvious.In simulated industrial atmosphere,the existence of hot-rolled oxide scale can facilitate the formation of dense rust layer on the surface of Q370qNH steel,which is more protective than bare steel.

New Progress in CNPC's Down Stream Ventures

ＮｅｗＰｒｏｇｒｅｓｓｉｎＣＮＰＣ＇ｓＤｏｗｎＳｔｒｅａｍＶｅｎｔｕｒｅｓＲｅｎＹｕｘｉａＤｕｒｉｎｇｔｈｅｐｅｒｉｏｄｏｆｔｈｅＥｉｇｈｔｈＦｉｖｅ－ＹｅａｒＰｌａｎ，Ｃｈｉｎａ＇ｓｏｎｓｈｏｒｅｐｅｔｒｏｌｅｕｍｉｎｄｕｓｔｒｙｓｔｅｐｐｅｄｆｏ...

玫瑰红景天不同采收期有效成分含量测定

目的建立玫瑰红景天中有效成分的含量测定方法,并检测不同采收期样品中红景天苷、络塞琳和络塞维含量。方法采用高效液相色谱仪,以X select HSS T3(250 mm×4.6 mm,5μm)为色谱柱,流动相为甲醇-乙腈和0.05%磷酸水溶液,梯度洗脱,流速1 ml/min,柱温30℃,进样量5μl,检测波长为275 nm(红景天苷)和254 nm(络塞琳、络塞维)。结果红景天苷、络塞琳和络塞维分别在44~1420、10~307、18~573μg范围内线性关系良好(r>0.999),精密度、稳定性、重复性和加样回收率均符合标准。玫瑰红景天块茎中红景天苷、络塞琳和络塞维含量高于须根,雌株中络塞维含量高于雄株(P<0.05),9月采收的玫瑰红景天中红景天苷、络塞琳和络塞维含量分别为0.66、0.07、0.53 mg/g。结论建立的方法简单快捷,适用于玫瑰红景天中有效成分含量的检测。9月采收的玫瑰红景天中红景天苷、络塞琳和络塞维含量最高。