基于PSI9816智能压力测量系统的应用研究与风洞实验

论述PSI9816智能压力测量系统的工作原理及硬件结构特点,利用LabWindows/CVI开发工具实现系统的模块功能及其工作流程,结合国家863计划"风力机先进翼型族的设计与实验研究"的翼型风洞实验实例,说明了PSI9816智能压力测量系统在风洞实验中的良好应用前景,具有很高的使用价值.     

Persistent Scatterers Interferometry detects and measures ground subsidence in Lisbon

Results from the application of Persistent Scatterers Interferometry in Lisbon Metropolitan Area revealed two previously unknown subsiding urban areas: one (Laranjeiras) is located in the center of Lisbon; another (Vialonga) is to be found toward the North, in an industrial region crossed by Lisbon's main highway and railway lines. The two subsiding sectors are bordered by sharp velocity gradients, and the subsidence pattern appears partially delimited by mapped geologic faults. Surface geology and urbanization alone are unable to explain the phenomena. In the Vialonga area, the historical record of water pore pressure shows a clear decline of the levels (up to 65 m in 27 years), providing evidence of over-exploitation of groundwater resources. Limited information from wells drilled inside and outside the subsidence area points to a spatial correlation between the subsidence and the water pressure levels, and suggests that faults could be acting as hydraulic barriers in the aquifer system. The surface subsidence detected is probably caused by compaction of a clay-rich Oligocene-aged aquitard, led by over-exploitation of adjacent aquifers. The same Oligocene aquitard layer is present in the Laranjeiras area, immediately bellow a multi-layered sand-clay-limestone Miocene aquifer, but further work is needed to diagnose the possibility of over-exploitation of groundwater here. In this work we were able to independently confirm the PSI results, by comparing autonomous PSI results processed for the same geographical areas, and by comparing PSI with leveling and continuous GPS derived subsidence velocities, whose close match provided further ground validation of the space-borne PSI technique.     

A new instrument for passive remote sensing: 2. Measurement of leaf and canopy reflectance changes at 531 nm and their relationship with photosynthesis and chlorophyll fluorescence

A previously described passive remote sensing fluorimeter (see companion paper) was modified to detect changes in the reflectance of vegetation. The utility of this remote sensing technique to measure the Physiological Reflectance Index (PRI) is shown at both leaf level under laboratory conditions and at the canopy level in the field. PRI, defined as the relative changes in reflectance at 531 nm with respect to those at 570 nm (PRI=R531−R570/R531+R570), is related to xanthophyll-related, dynamic changes of non-photochemical quenching of chlorophyll fluorescence. The robustness of this relationship by simultaneous remote sensing of PRI and chlorophyll fluorescence is strengthened. At the leaf level, the existence of two kinetically distinct components of PRI is shown. A fast (within seconds) component that is partly attributed to ΔpH induced chloroplast shrinkage, and a slow (within minutes), main component that is related to xanthophyll de-epoxidation, as demonstrated by its disappearance in the presence of DTT. Overall, PRI correlated better with non-photochemical quenching of chlorophyll fluorescence (NPQ) than with any other measured parameter, including the photochemical efficiency of PSII. Finally, at the canopy level and under field conditions, it is shown that PRI can be a useful tool for remote sensing of water stress in grapevines.     

数字电视机顶盒PSI/SI信息接收和存储方案设计

设计了一种改进型PSI/SI信息接收和存储方案。在接收过程中,通过改进section拼接技术实现section随机且无丢失的快速接收和拼接;在存储过程中,通过三级结构实现PSI/SI同级别信息的联合存储,方便了PSI/SI信息的查询。     

MELCOR/MACCS simulation of the TMI-2 severe accident and initial recovery phases, off-site fission product release and consequences

MELCOR has become the preferred code of the Swiss nuclear industry and of PSI for severe accident analysis, on account of its integrated systems-level approach and validation against experiments and more detailed codes, while MACCS is commonly used by safety authorities for independent assessment of off-site consequences, in particular health effects. The present work arises out of a programme to assess MELCOR independently using empirical data consistent with the recommendations of the OECD/CSNI validation matrix for core degradation codes. The MELCOR 1.8.5RD calculations are based on a model for phases 1 and 2 provided by the code developers but with a simplified thermal hydraulic noding in certain regions and the inclusion of a simple representation of the fission product release and transport pathways. The model has also been extended to simulate phases 3, 4, and the continuing initial period of core recovery and stabilisation. These calculations are a first attempt to demonstrate a MELCOR–MACCS capability to simulate the whole plant accident sequence beyond phase 4, including the containment response and off-site consequences arising from fission product release from the containment. Emphasis is placed on the overall accident evolution and whole plant response, rather than the detailed behaviour. Results are compared with observed and deduced data for the major accident signatures and rough estimates for exposure based on off-site monitoring. The results provide a good basis for the NPP analysis foreseen.     

PSI8400压力测试系统的Visual Basic设计

PSI8400电子压力测试系统是美国压力系统公司生产的高精度的压力测量设备，广泛应用在风洞压力测量试验中。本文介绍了在Visual Basic6．0环境下基于Ethemet接口的PS18400压力测试系统的软件设计实现。实验表明，该系统操作简单方便，运行稳定可靠，大幅提高了试验测量精度，节约了试验成本。     

机顶盒解复用器适配层的设计与实现

本文提出了一套机顶盒解复用器的设计和相关的接口函数 .它具有完备 ,简单 ,通用 ,易用的特点 ,支持应用程序的各种要求 ,数目少 ,抽象程度高 ,主要描述应用程序的要求 ,并且从 MPEG和 DVB标准出发 ,不涉及解复用器操作的细节 ,可在多个硬件平台上使用 ,为应用程序提供了一个稳定的开发环境 .能够很好地支持应用程序的开发 .文中详细地介绍了它的指导思想 ,概念 ,结构 ,所提供的服务 .同时 ,还介绍了实现这些函数的关键算法 .     

数字有线电视机顶盒节目指南的实现

本文介绍了电子节目指南信息的构成及MPEG-PSI和DVB-SI信息规范，提出了一种EPG信息的存储结构和节目数据库的生成方案，并据此介绍了如何在数字有线机顶盒中生成电子节目指南EPG。     

Psi(+)] prion generation in yeast: characterization of the 'strain' difference

The yeast cytoplasmically-inherited nonsense suppressor [PSI(+)] determinant is presumed to be a manifestation of the aggregated prion-like state of the Sup35 protein. Overexpression of the Sup35 protein induces generation of [PSI(+)] determinants with various suppressor efficiency and mitotic stabilities. Here, we demonstrate that the relative frequency of appearance of [PSI(+)] with different properties depends on the SUP35 allele used to induce their generation. The difference in properties of [PSI(+)] determinants was preserved after their transmission from one yeast strain to another. This difference correlated with variation in properties of the Sup35 protein. A novel type of prion instability was observed: some [PSI(+)] with weak suppressor efficiency could convert spontaneously into strong suppressor determinants.     

数字电视分前端系统集成的讨论

讨论地市级分前端系统构成与维护，分析不同节目源的特点及后续处理方法，结合本地节目插入对技术指标保障作具体分析，并就EPG信息的统一规划进行细致论述。