基于Vega Prime的多水下机器人视景仿真系统的设计与实现

介绍了一套多水下机器人三维视景仿真系统。该系统采用虚拟现实技术，利用虚拟仿真软件VegaPrime 与Visual C++.NET 2003 混合编程实现三维视景仿真。它主要用于海洋环境的模拟和多水下机器人运行时的位姿更新、碰撞检测、环境效果及各种特效的实时显示。此外，它还具有响应各种输入/输出设备的功能和通过人性化图形界面接口与用户进行交互的功能。

助推-远程滑翔三维飞行的热流峰值分析

为简便分析助推-远程滑翔弹道三维情况下的热流特性,基于远程滑翔三维飞行动力学模型和热力学基本公式,根据助推-远程滑翔弹道的两类飞行弹道（平衡滑翔弹道和跳跃滑翔弹道）的特点,推导建立了两类弹道三维情况下平均热流和驻点热流计算的解析公式。详尽分析了再入角、再入速度、升阻比、滚转角和翼载荷对两类弹道热流峰值的影响规律。由分析可知在远程滑翔三维飞行情况下,滚转角对其热流峰值有显著影响;升阻比大于1,滚转角控制在60度以内,其热流峰值能够得到有效降低。

Microstructure Evolution of Laser Pulse processed Ductile Iron Surface

Pulsed laser beam was used to modify surface processing for ductile iron. The microstructures of processed specimen were observed using optical microscope (OM). Nanoindentation and micro-hardness of microstructures were measured from surface to inner of sample. The experimental results show that, modification zone is consisted of light melted zone, phase transformation hardening area and transient area. The light melt area is made up of coarse dendrite crystalline with a thickness less than 20um, phase transformation hardening area mainly of laminal or acicular martensite, retained austenite and graphite, i.e. M+A prime+ G. The cow-eye microstructure around graphite sphere always is formed in phase transformation hardening area zone, which consisting of a variety structure with the distance from the surface. So, it maybe as a obvious sign distinguishing modification zone border. Finally, the microstructures evolution of laser pulse processed ductile iron was analyzed coupling with beam energy distribution in space and laser pulse heating procession characteristics. The analysis shows that energy distribution of laser pulse has an important effect on microstructure during laser pulse modified ductile iron. Multi-scale and interlace arrangement are the important features for laser pulse modified ductile iron. Of microstructure.

A scheme for multiple sequences alignment optimization-an improvement based on family representative mechanics features

As a basic tool of modern biology, sequence alignment can provide us useful information in fold, function, and active site of protein. For many cases, the increased quality of sequence alignment means a better performance. The motivation of present work is to increase ability of the existing scoring scheme/algorithm by considering residue–residue correlations better. Based on a coarse-grained approach, the hydrophobic force between each pair of residues is written out from protein sequence. It results in the construction of an intramolecular hydrophobic force network that describes the whole residue–residue interactions of each protein molecule, and characterizes protein's biological properties in the hydrophobic aspect. A former work has suggested that such network can characterize the top weighted feature regarding hydrophobicity. Moreover, for each homologous protein of a family, the corresponding network shares some common and representative family characters that eventually govern the conservation of biological properties during protein evolution. In present work, we score such family representative characters of a protein by the deviation of its intramolecular hydrophobic force network from that of background. Such score can assist the existing scoring schemes/algorithms, and boost up the ability of multiple sequences alignment, e.g. achieving a prominent increase (50%) in searching the structurally alike residue segments at a low identity level. As the theoretical basis is different, the present scheme can assist most existing algorithms, and improve their efficiency remarkably.

Number of phase levels of a Talbot array illuminator

The number of phase levels of a Talbot array illuminator is an important factor in the estimation of practical fabrication complexity and cost. We show that the number it) of phase levels of a Talbot array illuminator has a simple relationship to the prime number. When there is an alternative pi -phase modulation in the output array, the relations are similar. (C) 2001 Optical Society of America OCIS codes: 070.6760, 050.1950, 050.1980.

Symmetry of the Talbot effect and its applications

The Talbot effect is one of the most basic optical phenomena that has received extensive investigations both because its new results provide us more understanding of the fundamental Fresnel diffraction and also because of its wide applications. We summarize our recent results on this subject. Symmetry of the Talbot effect, which was reported in Optics Communications in 1995, is now realized as the key to reveal other rules for explanation of the Talbot effect for array illumination. The regularly rearranged-neighboring-phase-differences (RRNPD) rule, a completely new set of analytic phase equations (Applied Optics, 1999), and the prime-number decomposing rule (Applied Optics, 2001) are the newly obtained results that reflect the symmetry of the Talbot effect in essence. We also reported our results on the applications of the Talbot effect. Talbot phase codes are the orthogonal codes that can be used for phase coding of holographic storage. A new optical scanner based on the phase codes for Talbot array illumination has unique advantages. Furthermore, a novel two-layered multifunctional computer-generated hologram based on the fractional Talbot effect was proposed and implemented (Optics Letters, 2003). We believe that these new results should bring us more new understanding of the Talbot effect and help us to design novel optical devices that should benefit practical applications. (C) 2004 Society of Photo-Optical Instrumentation Engineers.

Microoptical research in Shanghai Institute of Optics and Fine Mechanics

This paper summarized the recent research results of Changhe Zhou's group of Information Optics Lab in Shanghai Institute of Optics and Fine Mechanics (SIOM). The first is about the Talbot self-imaging research. We have found the symmetry rule, the regular-rearranged neighboring phase difference rule and the prime-number decamping rule, which is briefly summarized in a recent educational publication of Optics and Photonics News, pp.46-50, November 2004. The second is about four novel microoptical gratings designed and fabricated in SIOM. The third is about the design and fabrication of novel supperresolution phase plates for beam shaping and possible use in optical storage. The fourth is to develop novel femtosecond laser information processing techniques by incorporating microoptical elements, for example, use of a pair of reflective Dammann gratings for splitting the femtosecond laser pulses. The most attractive feature of this approach is that the conventional beam splitter is avoided. The conventional beam splitter would introduce the unequal dispersion due to the broadband spectrum of ultrashort laser pulses, which will affect the splitting result. We implemented the Dammann splitting apparatus by using two-layered reflective Dammann gratings, which generates the almost same array without angular dispersion. We believe that our device is highly interesting for splitting femtosecond laser pulses.

液相外延法制备β-BBO薄膜

采用液相外延法在掺Sr^2＋的Q—BBO（001）衬底上制备了β-BBO薄膜，研究了制备条件对薄膜质量的影响．结果表明：当生长温度为810℃时，转速为300r／min生长的外延膜具有较高的结晶质量，且随着生长时间的延长，外延膜的结晶质量有所提高．β—BBO薄膜呈C轴高度择优取向，薄膜的双晶摇摆曲线半峰宽值FWHM仅为676．6”，表明β-BBO薄膜较好的结晶质量；在不具备相位匹配的条件下，β—BBO外延膜也能够实现二次谐波输出．

武汉市郊农田土壤中有机氯农药的残留分析

通过采集武汉市郊农田表层土壤,用GC-ECD法分析了土壤中HCH(六六六)、DDT(滴滴涕)及其代谢物的残留情况.结果表明:HCH残留低于DDT,∑HCHs介于0.18~18.90 ng.g-1,平均值为1.97 ng.g-1,∑DDTs介于1.82~165.34 ng.g-1,平均值为31.41 ng.g-1;残留水平较高的是p,p′-DDE、p,p′-DDD和p,p′-DDT.部分表层土壤中的∑DDTs超出了中国土壤环境质量标准的自然背景值.初步分析结果表明武汉市郊土壤中HCH及DDT的含量处于低浓度

基于光合色素的化学分类法在淡水藻类研究中的应用

采用反相高效液相色谱技术(RP-HPLC)系统研究了我国主要淡水藻类———蓝藻、绿藻、硅藻、甲藻、金藻、裸藻和隐藻等的光合色素,在8种纯培养藻类中共确定类胡萝卜素、叶绿素及其衍生物19种。分离到的主要标志性色素按洗脱时间分别为脱植基叶绿素a、19′-丁酰氧岩藻黄素、叶绿素c、脱镁叶绿素a、多甲藻素、甲基脱植基叶绿素a、岩藻黄素、新黄质、紫黄质、蓝藻叶黄素、硅甲藻黄素、硅藻黄质、叶黄素、玉米黄素、叶绿素b异构体、叶绿素b、叶绿素a异构体、叶绿素a和β-胡萝卜素;其中在纯培养的铜绿微囊藻中首次鉴定到19′-丁

阳光紫外辐射对室内水培发状念珠藻生理特性的影响

发状念珠藻(Nostoc flagelli forme Bornet & Flahault)是一种重要的陆生经济蓝藻,室内培育出的原植体如何适应阳光辐射的问题尚需探讨。为此,作者将室内水培发菜置于阳光下培养,测定了其生长、有效光化学效率(ΔF/F′m)和色素的变化。结果表明,较高的可见光(PAR,395—700nm)和紫外辐射(UVR,280—395nm)均导致水培发菜的ΔF/F′m下降。第1天中午,PAR和UVR分别使ΔF/F′m下降了54%和13%;傍晚,ΔF/F′m有部分恢复。UVR对发菜适应阳光2

两种东方鲀的GH基因单核苷酸多态性分析

根据红鳍东方鲀生长激素基因全序列,设计13对引物,结合单链构象多态性(SSCP)技术和克隆测序技术对野生红鳍东方鲀、养殖红鳍东方鲀和养殖暗纹东方鲀群体进行了遗传多样性分析。结果表明:东方鲀整个生长激素基因的6个外显子中没有多态性,在其内含子2、内含子5以及3′侧翼区发现有多处序列变异位点,包括碱基的缺失、插入和一些单核苷酸突变。这些遗传多态性的存在为从分子水平上对东方鲀的鉴定提供了一定的依据。群体遗传结构分析结果表明,红鳍东方鲀养殖群体的一些等位基因丧失,造成其遗传多样性显著下降,应及早加强对其种质的保护

草鱼免疫球蛋白M重链基因的克隆及表达

用RACE-PCR方法扩增出草鱼免疫球蛋白M(immunoglobulin M,IgM)分泌型的重链全长cDNA。其cDNA全长为1 940nt,包含5′非编码区20nt,3′非编码区189nt,开放阅读框1 731nt,编码576个氨基酸。序列比对分析表明草鱼IgM与鲤的相似性高达68%,与斑马鱼、斑点叉尾鱼回、鳜以及大西洋鳕的相似性分别为61%、43%、33%和30%。ClustalX比对结果显示:草鱼IgM中存在半胱氨酸和色氨酸的保守位点。进化分析表明,草鱼IgM与斑马鱼的IgM聚为一枝。荧光定量P

不同纬度螅状独缩虫耐热能力及Hsp70 mRNA表达水平的比较

本文以游泳体的形成作为虫体对热激响应的指征,比较了不同纬度(西安:东经108°98′,北纬34°25′;武汉:东经114°34′,北纬30°57′)两地螅状独缩虫(Carchesium polypinum)的耐热能力,发现武汉地区螅状独缩虫(WH株)形成游泳体的热激温度(36℃)高于西安地区(XA株)的33℃,说明前者的耐热能力较强;进一步利用实时PCR技术分析不同热激温度下两地螅状独缩虫热休克蛋白Hsp70mRNA的表达变化发现,XA株Hsp70mRNA热激后高表达水平的阈值温度为28℃,而WH株的为3