4 resultados para destination slogans

em Chinese Academy of Sciences Institutional Repositories Grid Portal


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A 2-D SW-banyan network is introduced by properly folding the 1-D SW-banyan network, and its corresponding optical setup is proposed by means of polarizing beamsplitters and 2-D phase spatial light modulators. Then, based on the characteristics and the proposed optical setup, the control for the routing path between any source-destination pair is given, and the method to determine whether a given permutation is permissible or not is discussed. Because the proposed optical setup consists of only optical polarization elements, it is compact in structure, its corresponding energy loss and crosstalk are low, and its corresponding available number of channels is high. (C) 1996 Society of Photo-Optical Instrumentation Engineers.

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籽粒的灌浆是将光合器官合成的有机物贮存在籽粒中的过程。这一过程直接决定了籽粒的产量及品质。先前研究表明灌浆籽粒中贮存物质的累积是各种代谢活动和细胞学过程协同作用的结果,但灌浆的分子机制目前还不是非常清楚。水稻是研究籽粒灌浆的优良模式材料,不仅因为它是世界上最重要的淀粉食物来源,更重要的是其全基因组的测序完成为分子机制的研究带来极大的便利。我们对发育水稻籽粒的观察表明在开花后6 天,籽粒就已完成了胚的分化和胚乳的细胞化;此后籽粒经历了一个显著的细胞增大过程,并在开花后12 天左右达到成熟籽粒的大小;而籽粒的灌浆过程起始于开花后6 天,这个过程一直持续到开花后20 天。因此,我们将开花后6 天到20 天的籽粒分为8 个连续的发育阶段进行动态的蛋白质组分析,396个蛋白点的表达在灌浆过程中发生了两倍以上变化。质谱鉴定得到的345 个差异表达的蛋白划分为10 个不同的功能类别。其中新陈代谢类(45%)和蛋白合成/终点(destination)类(20%)两个功能类别中就包括了大多数的差异表达蛋白,预示着这两类蛋白在籽粒发育中的重要性。蛋白功能群的表达分析显示与淀粉合成和乙醇发酵相关的蛋白在发育过程中大幅度的上调,而与碳代谢中心过程(糖酵解和三羧酸循环)相关蛋白呈现明显的下调趋势。大多数的功能类或(亚类)也呈现出下调的表达趋势,如细胞生长/分裂类,蛋白合成类,水解类,信号传导类和转录类。蛋白表达分析的结果表明蛋白的表达随籽粒的发育发生了显著的变化,这些变化与籽粒在不同阶段的发育和代谢过程密切相关并协调一致,是细胞从生长分裂过渡到以淀粉合成为中心的物质基础。同时也说明代谢重点由中心碳代谢向乙醇发酵的转变对于籽粒的发育和淀粉的合成与累积具有重要意义。 籽粒发育的研究表明在长到成熟籽粒大小后(开花后12 天),籽粒的代谢集中到淀粉累积途径上,一直持续到进入脱水期(18 天),绝大多数淀粉合成相关蛋白在这期间到达表达的顶点。为了解淀粉累积关键时期淀粉合成关键部位(胚乳)的发育规律,我们进一步应用DIGE 技术对这一淀粉累积关键时期(灌浆中后期,开花后12 到18 天)的蛋白表达特性进行分析。细胞学的观察发现胚乳在灌浆后期先后经历了过氧化氢的爆发、半透明胚乳的形成以及胚乳细胞死亡事件。相应的DIGE 分析显示有321 个蛋白点在胚乳的后期发育中发生了显著的表达变化。细胞学的观察结合DIGE 分析显示胚乳的后期发育是一个典型的衰老过程:细胞结构的崩溃;氧化自由基的爆发;脱水干燥;蛋白、脂类和DNA 由同化作用向异化作用的代谢转化。与代谢转化相伴随的细胞营养的重新分配是胚乳后期发育的一个显著过程。DIGE分析全面展示了参与营养重新分配相关蛋白在后期发育中的表达变化,为细胞学中观察到的有机物向淀粉的转化提供了清晰的蛋白水平的证据支持。在鉴定的差异表达蛋白中有2/3 的蛋白是已知的对氧化电位变化敏感的蛋白,表明由H2O2 爆发形成的氧化压力将引起氧化还原调控从而对胚乳的后期发育进行全面的影响。而其中与碳元素代谢相关的代谢途径中尤其富含氧化还原电位敏感的蛋白,表明后期的营养重新分配以及淀粉的累积受到氧化还原电位的紧密调控。另一方面,H2O2 的爆发激发了胚乳中的抗氧化体系。由抗氧化蛋白(如thioredoxin、抗坏血酸和超氧化物歧化酶等)、氧化还原敏感蛋白、代谢中间产物以及glyoxalase 构成的抗氧化体系在胚乳后期发育中协同作用调节氧化还原电位的变化,从而控制胚乳细胞衰老的节奏。另外,我们发现与RraA 相关的转录本的调控在胚乳发育末期急剧上调,在调控的代谢途径、调控时间以及调控的部位与氧化还原调控相重叠,并且支持RraA 活动有利于胚乳细胞对氧化压力的适应。所有这些结果表明内生的过氧化氢(或氧化自由基)在胚乳的后期发育和淀粉累积中起到核心的调控作用。

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本文研究水下机器人在障碍位置未知条件下,进行路径规划的方法,使自治水下机器人以最短的行程距离,避开障碍,达到预定目标.针对变化的、复杂的海洋情况,本文采用动态与静态相结合、规划与控制相结合的手段,应用人工势场理论,引入距离误差做动态反馈补偿,实现全局规划控制.本文提出的这种适于自治水下机器人导航的动态路径规划-控制方法,可以解决障碍环境参数已知、未知的路径规划问题.仿真结果表明该方法具有较强的稳定性和适应性.

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Junggar Basin has a large amount of recoverable reserves, However, due to the unfavorable factors, such as bad seismic data quality, complex structure with many faults and less wells, the exploration of oil and gas is still relatively limited, so advanced theoretical guidance and effective technical supports are desirable. Based on the theories of sedimentology, as well as comprehensive studies of outcrops, seismic data, drilling data and setting of this area, the paper establishes the isochronous correlation framework, and analyzes the sedimentary facies types and provenance direction, and obtains the profile and plain maps of the sedimentary facies combined with the logging constrained inversion. Then the paper analyzes the reservoir controlling factors, reservoir lithology attribute, 4-property relationship and sensibility based on the sedimentary facies research, and sets up a 3D geological model using facies controlled modeling. Finally, the paper optimizes some target areas with the conclusions of reservoir, structure and reservoir formation.Firstly, the paper establishs the isochronous correlation framework by the seismic data, drilling data and setting of this area. The sedimentary facies in Tai13 well block are braided river and meandering river according to the analysis of the lithology attribute, logging facies and sedimentary structure attribute of outcrop. The concept of “wetland” is put forward for the first time. The provenance direction of Badaowan and Qigu formation is obtained by the geology setting, sedimentary setting and paleocurrent direction. The paper obtains the profile and plain maps of the sedimentary facies from the sand value of the wells and the sand thickness maps from the logging constrained inversion. Then, this paper takes characteristics and control factors of the Jurassic reservoirs analysis on thin section observation, scanning transmission electron microscope observation and find out the petrology characteristics of reservoir, space types of reservoir and lithofacies division. In this area, primary pores dominate in the reservoir pores, which believed that sedimentation played the most important roles of the reservoir quality and diagenesis is the minor factor influencing secondary porosity. Using stochastic modeling technique,the paper builds quantitative 3-D reservoir Parameter. Finally, combined the study of structure and reservoir formation, the reservoir distribution regularity is concluded: (a) structures control the reservoir formation and accumulation. (b) Locating in the favorable sedimentary facies belt. And the area which meets these conditions mentioned above is a good destination for exploration.