基于改进VMD去噪的Prony-GSO联合谐波检测方法

针对传统Prony谐波检测方法在噪声条件下存在局限性,文章提出了一种能够在较大噪声条件下准确进行谐波检测的方法。通过对采样信号进行自适应的VMD分解,利用平均周期能量进行噪声模态的选择并予以剔除,将剩余模态重组后得到适合Prony算法的平稳信号,然后对平稳信号进行Prony谐波分析得到初步的谐波特征信息,最后对谐波特征信息进行循环筛选与GSO寻优,得到最终的谐波与间谐波特征信息。利用该方法进行谐波检测仿真实验,仿真结果表明,该方法有效提高了Prony算法在较大噪声条件下的辨识准确度,具有自适应性,能够自动筛选真实频率成分,具有高效、精确的优点。     

Detection of alpha-fetoprotein through biological signal amplification by biosensor based on imaging ellipsometry

High sensitive and quantitative detection of alpha-fetoprotein (AFP) by biosensor based on imaging ellipsometry (BIE) through biological amplification was investigated. AFP firstly reacted with the rat monoclonal antibody (rat-mAb) initially immobilized on glutaraldehyde modified silicon surface, then rabbit anti-human AFP polyclonal antibodies (Rabbit-pAb) and goat anti-rabbit IgG (goat-IgG) were sequentially applied to amplify signal. Results revealed that signal was enhanced approximately six fold. The linear range of AFP detection was 20.0-200.0 ng/ml with a low limit of 5.0 ng/ml (S/N = 3). The cross-reaction rate was less than 5.2% evaluated by biomarker (carcinoembryonic antigen, carbohydrate 19-9 and carbohydrate antigen 242) and two common proteins (human serum albumin, fibrinogen) and their mixture. Coefficient variation (CV) for intra-slide and inter-slide reproducibility were 10.3%, 6.6%, 6.3% and 10.7%, 7.9%, 6.4% for 41.6 ng/ml, 83.2 ng/ml and 128.4 ng/ml AFP. In clinic application, cut-off value at 28.6 ng/ml was also determined with sensitivity 0.72 and specificity 0.94. Results of 47 clinic patient samples detected by BIE were in good agreement with those of electrochemiluminescence immunoassay (ECLIA) (R2 = 0.9949).The area under receiver operating characteristic curve (ROC) curve is 0.89. Statistical analysis showed that BIE is high agreement with ECLIA (Kappa = 0.733, U = 3.21>U0.01). It shows a potential for hepatocellular carcinoma (HCC) diagnosis.     

插入式铜条转子并头套电阻硬钎焊工艺

为提高电动机中插入式铜条转子并头套的焊接质量，采用了电阻硬钎焊工,这样在改善劳动环境、降低劳动强度的同时提高了生产效率。     

医院改扩建中的功能环重铸

多组空间组合是综合医院的基本特性，在组合的过程中形成了功能环。医院发展到一定程度就会使之破裂，需要依据新的功能关系，重铸功能环。     

KOH modified Nafion112 membrane for high performance alkaline direct ethanol fuel cell

A polymer electrolyte membrane for alkaline direct ethanol fuel cell (ADEFC) was prepared by dipping Nafion112 membrane into KOH solution for some time at room temperature. The obtained membrane (Nafion112/KOH) exhibited higher mechanical properties and thermal stability than Nafion112 membrane. The ionic conductivity of Nafion112/KOH in 1 M, 2 M and 6 M KOH solutions was 0.011 S/cm, 0.026 S/cm, 0.032 S/cm, respectively, depending on internal OH⁻ concentration and the volume fraction of the internal aqueous phase. Single cell performance suggested that active ADEFC with Nafion112/KOH membrane can deliver a peak power density of 58.87 mW/cm² at 90 °C, meanwhile, it can stably run for at least 12 h above 0.2 V. On the other hand, Pt-free air breathing ADEFC with Nafion112/KOH can output a peak power density of 11.5 mW/cm² at 60 °C, and the corresponding lifetime was as long as 473 h above 0.3 V.     

Experimental study on grinding force and grinding temperature of Aermet 100 steel in surface grinding

This paper investigates grinding force and grinding temperature of ultra-high strength steel Aermet 100 in conventional surface grinding using a single alumina wheel, a white alumina wheel and a cubic boron nitride wheel. First, mathematical models of grinding force and grinding temperature for three wheels were established. Then, the role of chip formation force and friction force in grinding force was investigated and thermal distribution in contact zone between workpiece and wheel was analyzed based on the mathematical model. The experimental result indicated that the minimum grinding force and the maximum grinding force ratio under the same grinding parameters can be achieved when using a CBN wheel and a single alumina wheel, respectively. When the phenomenon of large grinding force and high grinding temperature appeared, the workpiece material would adhere locally to the single alumina wheel. Grinding temperature was in a high state under the effect of two main aspects: poor thermal properties of grinding wheel and low coolant efficiency. The predicted value of grinding force and grinding temperature were compared with those experimentally obtained and the results show a reasonable agreement.     

离心流化床干燥器研究进展

综述离心流化床干燥器的原理、设备结构、基础理论研究等方面的进展情况     

TRIZ TECHNOLOGY FORECASTING AS QFD INPUT WITHIN THE NPD ACTIVITIES

As a result of the fierceness of business competition, companies, to remain competitive,have to charm their customers by anticipating their needs and being able to rapidly develop excitingnew products for them. To overcome this challenge, technology forecasting is considered as a pow-erful tool in today's business environment, while there are as many success stories as there are fail-ures, a good application of this method will give a good result. A methodology of integration ofpatterns or lines of technology evolution in TRIZ parlance is presented, which is also known asTRIZ technology forecasting, as input to the QFD process to design a new product. For this purpose,TRlZ technology forecasting, one of the TRIZ major tools, is discussed and some benefits comparedto the traditional forecasting techniques are highlighted. Then a methodology to integrate TRIZtechnology forecasting and QFD process is highlighted.     

中压配电网的衍生接线模式

小区负荷发展在时间上是一个S形状,经历三个阶段:早期、中期和饱和期。本文研究了随小区负荷S形发展,接线模式的变化规律,提出中压配网衍生接线的思想。该思想利用较高负载率的接线模式,用时变的观点规划配电网络,选择接线模式;并针对架空线网和电缆网分别作了研究,指出架空线网的衍生经历了放射状网、“手拉手”网、多馈线联络到n-1网的过程;电缆网的衍生经历了“手拉手”网、双∏型网到多分段多联络网络的过程。衍生出的高负载率的接线模式与配电网自动化配合,具有推迟新建项目的潜在经济效益,优化了整个中压配电网络,并在对比了经济效益的基础上对杭州市规划新建小区提出了应用建议。