新型冷轧(拔)无缝钢管高分子润滑工艺研究

提出了冷轧(拔)无缝钢管高分子润滑工艺。研究了该工艺的PL膜各种特性。介绍了工业实验情况。实验证明,高分子润滑工艺完全满足冷轧(拔)钢管工艺要求,并具有操作简便、环境污染小等优点,完全可以代替传统的磷化-皂化润滑工艺。     

SHS制备陶瓷内衬复合管中多孔层抑制措施

研究了在重力自蔓延法制备陶瓷内衬复合钢管过程中在复合热管底部出现的多孔层现象,以及各类添加剂对其的影响,分析了多孔层出现的原因,探讨了抑制措施。试验结果表明,SiO2的存在是产生多孔层的主要原因,并且多孔层部分随着SiO2含量的增加而增加,助燃剂也能导致多孔层的出现。当SiO2的质量分数小于2%时,适量加入氟化物,可以有效减少多孔层的体积。     

粘土砂旧砂再生效果与其含水量的关系

在影响粘土砂旧砂再生效果的诸多因素中,旧砂中水分含量是最重要的因素。本文就水分含量对再生效果的影响规律、再生效果最佳的水分含量等进行了研究和分析,得出了如下结论:并非含水量越低再生效果就越好,而是存在一个去泥率低谷区;再生效果最佳的适宜水分含量为1～2%。     

含B2O3渣系的热力学计算模型

根据炉渣结构的共存理论和相图，推导了ＣａＯＢ２Ｏ３和ＦｅＯＦｅ２Ｏ３Ｂ２Ｏ３渣系的热力学计算模型。结果表明：（１）理论计算的ＣａＯＢ２Ｏ３渣系的作用浓度ＮＣａＯ及ＮＢ２Ｏ３与实测的活度ａＣａＯ及ａＢ２Ｏ３一致；（２）理论计算的ＦｅＯＦｅ２Ｏ３Ｂ２Ｏ３渣系的氧化能力ＮＦｅｔＯ与实测的炉渣ＦｅｔＯ的活度值相符合。这说明本文提出的热力学计算模型是合理的。     

Anti-periodic solutions in a ring of four neurons with multiple delays

This paper is concerned with the existence and exponential stability of anti-periodic solutions of bidirectional associative memory (BAM) neural networks with multiple delays. Applying inequality techniques and Lyapunov method, Sufficient conditions which ensure the existence and exponential stability of anti-periodic solutions of the BAM neural networks are presented. Our results are new and supplement some previously known ones.     

A comparison between atmospheric water vapour content retrieval methods using MSG2-SEVIRI thermal-IR data

Atmospheric water vapour content (WVC) is a vital parameter in the study of climate change. Various methods have been developed to derive atmospheric WVC from remotely sensed data. In this study, we compared three methods for retrieving atmospheric WVC from thermal infrared data in the Meteosat Second Generation-SEVIRI channels 9 (10.8 μm) and 10 (12.0 ?m). The three methods are (1) the split-window covariance-variance ratio method using a spatial moving window (method 1); (2) the split-window covariance-variance ratio method using a temporal moving window (method 2); and (3) the varying surface temperature method using split-window channel data (method 3). The derived WVC using these three methods was compared to two WVC data sets from European Centre for Medium-Range Weather Forecasts (ECMWF) reanalysis data and the MODIS WVC product. Compared with these two data sets, the derived WVC using method 1 performed proved optimal. The valid pixels using methods 1 and 2 are greater than those using method 3. Furthermore, method 2 can be used to retrieve WVC over pixels where method 1 is invalid.     

The implications of serial correlation and time-lag effects for the impact study of climate change on vegetation dynamics – a case study with Hulunber meadow steppe,Inner Mongolia

Ecological time series data are widely used in ecological research thanks to the development of remote-sensing technologies and fixed ecological research stations. However, the serial correlation issue with time series, which violates the fundamental assumption of independence for traditional statistical models or analysis, is rarely considered by ecologists in vegetation–climate relationship research. In addition, the issue of time lags between climate change and vegetation response is also often ignored. Inadequate consideration of these issues produces misleading results in some cases. In this article, we propose an approach based on the Autoregressive Integrated Moving Average (ARIMA) model and the nonparametric test to address serial correlation issue and distribution requirements for the valid statistical analysis of time series data. With Hulunber meadow steppe as a case, we applied this approach to analyse the role of climate factors in vegetation dynamics based on leaf area index (LAI) data and climatic data. The results showed that the LAI dynamics of Hulunber meadow steppe were mainly related to temperature with the time lag of zero, whereas the impact of precipitation on LAI dynamics was not statistically obvious. The comparison of regression models that deal with serial correlation and residual normality to different extents showed that ignoring the serial correlation issue with time series data likely produces misleading results, highlighting the importance of serial correlation removal. The combination of nonparametric correlation tests with ARIMA-based cross-correlation analysis also proved quite useful in reducing the chance of spurious correlation and time lags resulting from outlier values in ARIMA-based cross-correlation.     

Distilled Collections from Textual Image Queries

We present a distillation algorithm which operates on a large, unstructured, and noisy collection of internet images returned from an online object query. We introduce the notion of a distilled set, which is a clean, coherent, and structured subset of inlier images. In addition, the object of interest is properly segmented out throughout the distilled set. Our approach is unsupervised, built on a novel clustering scheme, and solves the distillation and object segmentation problems simultaneously. In essence, instead of distilling the collection of images, we distill a collection of loosely cutout foreground “shapes”, which may or may not contain the queried object. Our key observation, which motivated our clustering scheme, is that outlier shapes are expected to be random in nature, whereas, inlier shapes, which do tightly enclose the object of interest, tend to be well supported by similar shapes captured in similar views. We analyze the commonalities among candidate foreground segments, without aiming to analyze their semantics, but simply by clustering similar shapes and considering only the most significant clusters representing non‐trivial shapes. We show that when tuned conservatively, our distillation algorithm is able to extract a near perfect subset of true inliers. Furthermore, we show that our technique scales well in the sense that the precision rate remains high, as the collection grows. We demonstrate the utility of our distillation results with a number of interesting graphics applications.     

红外球形摄像机补光系统的设计与实现

为解决目前红外球形摄像机普遍存在的红外灯板发热严重、近距离采集图像容易出现中心过曝等问题,搭建了以STM32F103为主控芯片、以PT4115为红外灯调光芯片的硬件电路,设计了一种基于红外灯亮度与镜头倍率匹配算法的新型红外球形摄像机补光系统,实现了在红外灯板上对多个串联红外灯的PWM智能调光。通过实验证明,该设计可以有效节约功耗、降低发热,提高了红外灯板的稳定性,从而提高红外球形摄像机的夜视监控效果。