Retrieving ocean surface current by 4-D variational assimilation of sea surface temperature images

In this article we propose a new method to estimate ocean mesoscale structures of the surface current velocity by processing sea surface satellite images. Assuming that the intensity level can be described by a transport-diffusion equation, the proposed approach is based on variational assimilation of image observations within a simple transport-diffusion model. This approach permits to retrieve the current velocity field from a sequence of satellite images. Results of processing synthetic data and real NOAA-AVHRR satellite images are presented and commented.     

肺癌组织中SOX4突变蛋白三级结构的建模及分析

SOX家族与很多人类肿瘤的发生有关.对人类肺癌组织中的SOX4进行测序,发现该基因HMG-box区有突变发生并导致SOX4蛋白的107密码子发生突变.以三级结构已知的SOX2为模板,采用同源建模方法对突变和正常SOX4蛋白FMG-box进行建模.结果显示突变和正常SOX4蛋白的三级结构很相似,且突变导致107密码子位置的侧链结构不稳定.提示该位置的不稳定可能会影响突变SOX4蛋白侧链的弹性,并有可能影响相应蛋白的功能.表面静电分析显示SOX4蛋白C端有一个可能与其它小分子或蛋白质的相互作用位点的N/C腔.这些结果显示SOX4蛋白的上述空间结构可能与其活性与功能的调控有关,而SOX4突变可能与肺癌的发生和转移有关.     

四腿机器人步态参数自动进化研究与实现

采用进化算法和基于自主视觉的适应度评估方法,实现了四腿机器人在RoboCup机器人足球比赛现场的行走步态在线自动进化．我们引入内推法作为交叉方法,利用PC基站进行进化算法计算和流程主控,并采用了一些学习时间缩减策略．实现了进化学习的连续性和可扩展性,使得学习过程可以在4060min内完成,这样就能在比赛现场对ERS-7四足机器人进行行走再学习,提高了行走控制的适应性．算法最终结果使ERS-7型四足机器人的行走速度从27cm/s提升到43cm/s．     

Preozonation of Chlorophenolic Wastewater for Subsequent Biological Treatment

Preozonation was investigated for its effects on the biodegradability of five chlorophenolic compounds in activated-sludge systems. The biodegradability was expressed in terms of the oxidation of each compound itself and of the total organic contents of the whole sample.

Results indicate that preozonation could either promote or retard the biodegradability, depending primarily on whether or not the sludge used in the subsequent biological system had been acclimated beforehand. For unacclimated sludge, preozonation was found to be helpful in promoting the biodegradability of all the compounds, especially the chlorophenols with a meta-position chlorine attachment. For acclimated sludge, a reverse effect generally, was observed.     

合成介质对PEDOT催化染料敏化太阳电池光阴极性能的影响

采用聚3,4-乙烯二氧噻吩(PEDOT)/FTO为对电极,研究了合成介质对循环伏安法电聚合制备的PEDOT/FTO对电极性能的影响。通过SEM、CV、EIS、Tafel曲线,并首次采用SECM方法对所制备的对电极的电催化性能进行了表征。结果表明:在LiClO4水溶液和1-丁基-3-甲基四氟硼酸盐离子液体(IL)中制备的光阴极具有良好的电催化性能。J-V测试曲线表明,在LiClO4水溶液和IL中制备的光阴极所组装的DSSC器件的光电转化效率分别达6.4%和6.6%,接近于同等条件下以Pt对电极构建的DSSC器件的光电转化效率。     

CoNi2S4 Nanoparticle/Carbon Nanotube Sponge Cathode with Ultrahigh Capacitance for Highly Compressible Asymmetric Supercapacitor

Compared with other flexible energy‐storage devices, the design and construction of the compressible energy‐storage devices face more difficulty because they must accommodate large strain and shape deformations. In the present work, CoNi₂S₄ nanoparticles/3D porous carbon nanotube (CNT) sponge cathode with highly compressible property and excellent capacitance is prepared by electrodepositing CoNi₂S₄ on CNT sponge, in which CoNi₂S₄ nanoparticles with size among 10–15 nm are uniformly anchored on CNT, causing the cathode to show a high compression property and gives high specific capacitance of 1530 F g⁻¹. Meanwhile, Fe₂O₃/CNT sponge anode with specific capacitance of 460 F g⁻¹ in a prolonged voltage window is also prepared by electrodepositing Fe₂O₃ nanosheets on CNT sponge. An asymmetric supercapacitor (CoNi₂S₄/CNT//Fe₂O₃/CNT) is assembled by using CoNi₂S₄/CNT sponge as positive electrode and Fe₂O₃/CNT sponge as negative electrode in 2 m KOH solution. It exhibits excellent energy density of up to 50 Wh kg⁻¹ at a power density of 847 W kg⁻¹ and excellent cycling stability at high compression. Even at a strain of 85%, about 75% of the initial capacitance is retained after 10 000 consecutive cycles. The CoNi₂S₄/CNT//Fe₂O₃/CNT device is a promising candidate for flexible energy devices due to its excellent compressibility and high energy density.     

An inexact hybrid projection-proximal point algorithm for solving generalized mixed variational inequalities

In this paper, we investigate an inexact hybrid projection-proximal method for solving a class of generalized mixed variational inequalities in Hilbert spaces. We construct a general inexact hybrid projection-proximal point algorithm, in which an inexact relaxed proximal point step is followed by a suitable orthogonal projection onto a hyperplane. Under some suitable conditions concerned with the pseudomonotone set-valued mapping T, the nonsmooth convex function f and the step size λ_k, we prove the convergence of the inexact hybrid projection-proximal point algorithm for solving generalized mixed variational inequalities in Hilbert spaces.     

Strong stability of the mono-tubular heat exchanger equation with output feedback

We investigate asymptotic behavior of the C₀-semigroup T(t) associated with the mono-tubular heat exchanger equation with output feedback by a perturbation method. It is shown that T(t) is bounded if a constraint is satisfied by the parameters and the spatial distribution function. Further, applying the Arendt-Batty-Lyubich-Vu theorem, a criterion is established to judge strong stability of T(t).     

Δ3-1,2,4—噻二唑类化合物的量子化学及构效关系研究

Δ3-1,2,4—噻二唑类化合物具有抑制黄瓜霜霉病毒的杀菌活性。本文用半经验PM3方法对25个该类化合物进行了量子化学计算,并依据原子的净电荷、前沿轨道能级、轨道主要成分及原子在前沿轨道中所占比重等计算结果和多重回归分析讨论了该类化合物的活性部位,为该类化合物结构与活性的研究奠定了理论基础。     

用于半自动视频对象提取的自适应网格图像分割

随着MPEG－4标准的发展和基于内容的视频处理研究,视频对象平面（VOP）的有效产生成为一个关键问题。本文提出一种基于区域的自适应网格彩色图像分割方法,可用于获得半自动视频对象跟踪和提取所需的初始VOP。该方法利用CIE L＊a*b＊色彩空间的特征量,对视频序列的第一帧进行三角形网格的分裂与合并。对MPEG－4标准测试序列的分割实验取得了较好的结果。