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101.
借鉴国际管道技术委员会对输气管道提出的失效原因以及RBI思路,利用“专家打分法”对管道安装、维护、保养、检验等各个环节,量化发生事故的可能性和后果的严重程度,从而以半定量法确定在用工业管道风险值,进而进行风险预警,为压力管道使用单位、河北省质监局安全监察工作提出合理化建议。 相似文献
102.
103.
简介四喷嘴对置式气化炉烧嘴冷却水泵回路配置及联锁设置的情况,针对运行过程中出现的诸多问题,分析其原因,并采取了一系列优化、改造措施,由此保障了气化炉的长周期稳定运行。 相似文献
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105.
以2006-2012年我国所发表的关于关联数据的论文为分析数据,采用文献定量分析的方法进行统计分析,从时间分布、作者分布、期刊分布、研究资助基金分布和主题分布几个方面来分析我国关联数据研究的现状。同时,总结研究中尚存在的不足,探讨研究发展的趋势。 相似文献
106.
P. R. Underhill 《Research in Nondestructive Evaluation》2013,24(2):92-104
Fatigue cracks are prone to develop around the fasteners found in multilayer aluminum structures such as ageing aircraft. The determination of their probability of detection (POD) using eddy current techniques is critical for risk assessments used in evaluating serviceability. Normally, a large number of samples of both fatigue cracks and electric discharge machined notches are required for such a study. In this study, the use of quantitative fractography (QF) to efficiently gather POD data for bolt hole eddy current is demonstrated. The technique can be readily automated, significantly reducing man-hour requirements. The method is applied to mid-bore cracks, grown without starter notches, in order to simulate naturally occurring fatigue cracks. POD of the mid-bore cracks is examined using a probit analysis. An a 90/95 is the probability that 90% of the cracks of size a or larger will be detected 95% of the time. An a 90/95 of 0.34 mm was obtained for mid-bore crack depth. This value is consistent with skin depth considerations at the 1.6 MHz inspection frequency. An examination of the POD based on crack length found that it was related to that of depth according to the average length-to-depth aspect ratio of 2 to 1. 相似文献
107.
Magdalena Luczak Joanna Suszynska-Zajczyk Lukasz Marczak Dorota Formanowicz Elzbieta Pawliczak Maria Wanic-Kossowska Maciej Stobiecki 《International journal of molecular sciences》2016,17(5)
The major cause of mortality in patients with chronic kidney disease (CKD) is atherosclerosis related to traditional and non-traditional risk factors. However, the understanding of the molecular specificity that distinguishes the risk factors for classical cardiovascular disease (CVD) and CKD-related atherosclerosis (CKD-A) is far from complete. In this study we investigated the disease-related differences in the proteomes of patients with atherosclerosis related and non-related to CKD. Plasma collected from patients in various stages of CKD, CVD patients without symptoms of kidney dysfunction, and healthy volunteers (HVs), were analyzed by a coupled label-free and mass spectrometry approach. Dysregulated proteins were confirmed by an enzyme-linked immunosorbent assay (ELISA). All proteomic data were correlated with kidney disease development and were subjected to bioinformatics analysis. One hundred sixty-two differentially expressed proteins were identified. By directly comparing the plasma proteomes from HVs, CKD, and CVD patients in one study, we demonstrated that proteins involved in inflammation, blood coagulation, oxidative stress, vascular damage, and calcification process exhibited greater alterations in patients with atherosclerosis related with CKD. These data indicate that the above nontraditional risk factors are strongly specific for CKD-A and appear to be less essential for the development of “classical” CVD. 相似文献
108.
This paper introduces a novel control approach to maximizing the output energy of an adjustable slope angle wave energy converter (ASAWEC) with oil-hydraulic power take-off. Different from typical floating-buoy WECs, the ASAWEC is capable of capturing wave energy from both heave and surge modes of wave motions. For different waves, online determination of the titling angle plays a significant role in optimizing the overall efficiency of the ASAWEC. To enhance this task, the proposed method was developed based on a learning vector quantitative neural network (LVQNN) algorithm. First, the LVQNN-based supervisor controller detects wave conditions and directly produces the optimal titling angles. Second, a so-called efficiency optimization mechanism (EOM) with a secondary controller was designed to regulate automatically the ASAWEC slope angle to the desired value sent from the supervisor controller. A prototype of the ASAWEC was fabricated and a series of simulations and experiments was performed to train the supervisor controller and validate the effectiveness of the proposed control approach with regular waves. The results indicated that the system could reach the optimal angle within 2s and subsequently, the output energy could be maximized. Compared to the performance of a system with a vertically fixed slope angle, an increase of 5% in the overall efficiency was achieved. In addition, simulations of the controlled system were performed with irregular waves to confirm the applicability of the proposed approach in practice. 相似文献
109.
通过主要滋味成分化学分析和滋味定量描述分析相结合技术对绿茶茶汤的滋味进行研究。结果表明,绿茶茶汤中各主要滋味成分含量差异较大;对于同一滋味成分而言,不同茶汤中的含量也有一定差异。茶多酚(TP)、表没食子儿茶素没食子酸酯(EGCG)、表没食子儿茶素(EGC)、咖啡喊(Caf)、表儿茶素没食子酸酯(ECG)、芦丁(Rutin)、D-儿茶素(D-C)、表儿茶素(EC)、氨基酸(AA)等9个成分对绿茶茶汤滋味的贡献较大,各滋味间强度关系为涩味〉苦味〉鲜味〉甜味。通过主成分分析提取出的2个主成分数据、绿茶茶汤滋味定量描述结果对35个绿茶样品分别进行聚类,结果表明绿茶茶汤中各滋味成分之间存在着协同作用。 相似文献
110.
物相定量分析在铝工业中的应用 总被引:1,自引:0,他引:1
总结介绍了到目前为止在铝工业中应用的物相定量分析方法,分析了各种方法的应用范围以及优缺点,包括化学物相定量法、外标法、化学物相计算法、X射线衍射增量法、K值法、绝热法、Rietveld全谱拟合定量法、K值法和化学物相计算法结合以及Zevin无标定量法等.结果表明:每种物相定量分析方法都有各自的优点和缺点,需要根据样品的... 相似文献