CO2气层录井识别影响因素分析与解释评价

松辽盆地南部深层天然气储集层富含CO2,随着勘探的深入进行,CO2气层的录井识别与评价难题已突显,主要表现为异常发现和分层困难,无法定量评价。从CO2特殊的物理化学性质分析入手,通过实验分析,确认了CO2气层录井出现分层和评价困难的主要原因是CO2在水中的高溶解度、高扩散性和溶于水后产生的弱酸性。进一步通过研究CO2与甲烷录井密切的伴生关系以及甲烷气的录井显示灵敏性,结合钻时、CO2与甲烷的相对含量高低等录井参数,在现有技术条件下,初步建立了CO2气层的录井识别评价方法。     

基于FlexPDE研究顺电相KTN晶体中大调制度全息光栅的形成

在用带输运模型研究光折变效应时,大多数情况下都限定入射的相干光调制度远小于1,对方程做线性化近似以便于求解,这在求解小调制度问题时可以达到满意的精度。但在很多实际情况下光调制度接近于1,此时线性理论不再适用。基于FlexPDE程序提出了一种新的求解方法,适用于大调制度时的情况。采用有限元算法,严格求解光折变带输运方程,研究了外加电场时顺电相KTN晶体中大调制度全息光栅的形成,给出了晶体中的空间电荷场、光激发电子、离化施主、晶体折射率等的分布情况和时间演化曲线。计算结果表明,采用FlexPDE程序不仅可以大大降低带输运模型的求解难度,而且能够实时动态显示全息光栅的形成过程,具有直观性。     

基于最小一乘的遥感图像融合

基于全色数据与多光谱数据之间的线性关系进行遥感图像融合是一种可行并被广泛应用的思路.本文利用GCOS模型对GS方法进行了分析,发现GS法可通过最小二乘法进行线性回归.由于最小一乘与最小二乘相比更为稳健,因此预期采用最小一乘法的融合方珐具有更好的性能.本文提出了一种基于最小一乘融合方法的构建,并对IKONOS数据进行了对比试验.试验结果表明,基于最小一乘的融合方法是对GS方法的一种有效改进.     

Rational Designs for Lithium-Sulfur Batteries with Low Electrolyte/Sulfur Ratio

Lithium-sulfur batteries (LSBs) are considered a promising next-generation energy storage device owing to their high theoretical energy density. However, their overall performance is limited by several critical issues such as lithium polysulfide (PS) shuttles, low sulfur utilization, and unstable Li metal anodes. Despite recent huge progress, the electrolyte/sulfur ratio (E/S) used is usually very high (≥20 µL mg⁻¹), which greatly reduces the practical energy density of devices. To push forward LSBs from the lab to the industry, considerable attention is devoted to reducing E/S while ensuring the electrochemical performance. To date, however, few reviews have comprehensively elucidated the possible strategies to achieve that purpose. In this review, recent advances in low E/S cathodes and anodes based on the issues resulting from low E/S and the corresponding solutions are summarized. These will be beneficial for a systematic understanding of the rational design ideas and research trends of low E/S LSBs. In particular, three strategies are proposed for cathodes: preventing PS formation/aggregation to avoid inadequate dissolution, designing multifunctional macroporous networks to address incomplete infiltration, and utilizing an imprison strategy to relieve the adsorption dependence on specific surface area. Finally, the challenges and future prospects for low E/S LSBs are discussed.     

AN H∞ FUZZY TRACKING CONTROL SCHEME FOR AFFINE COUPLED SPATIO-TEMPORAL CHAOS

Due to the interactions among coupled spatio-temporal subsystems and the constant bias term of affine chaos, it is difficult to achieve tracking control for the affine coupled spatiotemporal chaos. However, every subsystem of the affine coupled spatio-temporal chaos can be approximated by a set of fuzzy models; every fuzzy model represents a linearized model of the subsystem corresponding to the operating point of the controlled system. Because the consequent parts of the fuzzy models have a constant bias term, it is very difficult to achieve tracking control for the affine system. Based on these fuzzy models, considering the affine constant bias term, an H∞ fuzzy tracking control scheme is proposed. A linear matrix inequality is employed to represent the feedback controller, and parameters of the controller are achieved by convex optimization techniques. The tracking control for the affine coupled spatio-temporal chaos is achieved, and the stability of the system is also guaranteed. The tracking performances are testified by simulation examples.     

Discrimination of Smoke Particles Using Infrared Photoelectrical Detection

A method of discrimination of smoke particles using infrared photoelectrical detection is proposed in this paper. Principle of the method is that smoke particles of different materials have different scattering light intensities at same scattering angle according to Mie Theory. Facility used to realize the method includes an infrared laser as light source and an array of avalanche photodiodes distributed at assigned angles as sensing devices. Scattered light signal at these angles are collected and processed. Categories of smoke particle are discriminated by signal processing results. Experiments show that by using this method cigarette smoke, kerosene smoke and water vapor can be discriminated with rate of discrimination of greater than 95%. Application of this technology in the field of fire detection will eliminate some effects of human activities such as cigarette smoking and steam on smoke detection, and improve sensitivity as well as reliability of smoke detection.     

60km车载瑞利测风激光雷达研制

目前我国尚缺乏25~60 km大气风场实时探测手段,为此研制了60 km车载瑞利测风激光雷达。介绍了系统总体结构,对分系统的研制做了详细描述。为提高风场反演的精度,设计了标准具通过率函数校准系统。提出了标准具通过率函数校准方法,并开展实验对标准具通过率函数进行了校准。校准结果表明,接收机性能稳定,各参数测量标准差均小于0.06。该系统在德令哈地区对15~60 km大气风场进行了观测,获得了水平风场的测量结果,并与当地探空气球的探测结果进行了比对,30 km以下一致性较好。对风速、风向测量误差进行了计算,40 km以下,风速测量误差4 m/s,风向测量误差6,40 km以上,风速测量误差8 m/s,风向测量误差18。该系统设计合理,性能稳定,能够实时探测10~60 km大气风场。     

浅谈元器件失效分析在质量问题归零中的作用

本文首先简要介绍了元器件失效分析的目的和作用以及基本实施程序,然后针对我所在质量问题归零过程中存在的集成电路失效原因及机理定位不准确,纠正措施不到位的问题,举例说明了近期在某质量问题归零工作过程中通过委托工信部电子5所进行失效分析,明确了芯片失效原因,进而实现了彻底归零。实践证明,元器件失效分析对于准确定位器件失效原因及机理,从而促进质量问题彻底归零有着关键作用。     

适用于计算机绘图的数据结构浅议

计算机绘图中的数据处理,图学者往往感到棘手。本文介绍一种方便可行的数据结构,并举例说明其应用。