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1.
本文描述了Solaris2.X操作系统上网络文件系统NFS的特性及其环境配置,介绍了如何建立了NFS服务器和NFS客户机,从而实现了远程文件系统资源共享。 相似文献
2.
住宅厨房共用排烟系统性能比较 总被引:3,自引:1,他引:2
介绍了当地住宅厨房通风设计的发展简况,比较了两种房共用排烟系统的构造,尺寸,性能,造价及能耗,对厨房通风设计和施工提出了建议。 相似文献
3.
从数字看发展片式电容器面临的机遇与挑战 总被引:11,自引:2,他引:9
采用海关进、出口统计和行业生产统计资料,通过计算、分析,用数字来说明国内发展片式多层陶瓷电容器、片式钽电解电容器、片式铝电解电容器、片式有机薄膜电容器所面临的机遇与挑战,并对其国内市场需求总量、额,国产品在国内市场占有率等做出评估,为有关单位了解片式电容器的发展提供参考,为国产产品更有效地进入国内市场、促进其发展提供依据。 相似文献
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5.
R. van Tijum 《Surface & coatings technology》2007,201(8):4633-4639
This paper concentrates on revealing the local deformation as a function of applied strain in a polymer coating supported by a plastically deforming and roughening metal substrate. To this end in-situ birefringence microscopy measurements have been executed. The measurements are performed in reflection and an alternative unwrapping scheme for the optical path difference is proposed. From the characterization of PET (polyethylene terephthalate) coated stainless steel it is concluded that strain localization appears below the macroscopic strain at yield and that the surface roughness of the substrate is the driving force of the localization. 相似文献
6.
Impacts of spectral band difference effects on radiometric cross-calibration between satellite sensors in the solar-reflective spectral domain 总被引:2,自引:0,他引:2
In order for quantitative applications to make full use of the ever-increasing number of Earth observation satellite systems, data from the various imaging sensors involved must be on a consistent radiometric scale. This paper reports on an investigation of radiometric calibration errors due to differences in spectral response functions between satellite sensors when attempting cross-calibration based on near-simultaneous imaging of common ground targets in analogous spectral bands, a commonly used post-launch calibration methodology. Twenty Earth observation imaging sensors (including coarser and higher spatial resolution sensors) were considered, using the Landsat solar reflective spectral domain as a framework. Scene content was simulated using spectra for four ground target types (Railroad Valley Playa, snow, sand and rangeland), together with various combinations of atmospheric states and illumination geometries. Results were obtained as a function of ground target type, satellite sensor comparison, spectral region, and scene content. Overall, if spectral band difference effects (SBDEs) are not taken into account, the Railroad Valley Playa site is a “good” ground target for cross calibration between most but not all satellite sensors in most but not all spectral regions investigated. “Good” is defined as SBDEs within ± 3%. The other three ground target types considered (snow, sand and rangeland) proved to be more sensitive to uncorrected SBDEs than the RVPN site overall. The spectral characteristics of the scene content (solar irradiance, surface reflectance and atmosphere) are examined in detail to clarify why spectral difference effects arise and why they can be significant when comparing different imaging sensor systems. Atmospheric gas absorption features are identified as being the main source of spectral variability in most spectral regions. The paper concludes with recommendations on spectral data and tools that would facilitate cross-calibration between multiple satellite sensors. 相似文献
7.
基于P2P的云计算模型及其安全性分析 总被引:1,自引:0,他引:1
文章通过将P2P技术和云计算相结合,提出了一种可靠的、可扩展的、低成本的文件共享模型PA-Cloud。该文介绍了PA-Cloud的文件下载和更新过程,并对系统的安全性进行了分析。通过对PA-Cloud进行对比实验表明,PA-Cloud可以有效提高系统的可扩展性,降低服务提供商的成本。 相似文献
8.
将5G无线通信基站安装在电力线杆塔上,可以通过电力线路杆塔共享促进5G网络建设,实现电力企业和通信公司的互利共赢。重点讨论了5G基站的新架构,分析了把基站应用到电力杆塔上应考虑的供电、接地、安装等问题,并给出了相应的解决方案。 相似文献
9.
Heinz Ludwig 《Desalination》2004,164(1):1-18
Ever since seawater desalination has been applied on an industrial scale, and particular in the countries of the Arabian Gulf, the application of desalination processes in dual-purpose facilities—water and power—as a hybrid configuration has been discussed in many feasibility investigations and also planning concepts. It is above all the combination of reverse osmosis with thermal processes that has found increasing interest with the aim of ensuring, as economically as possible, uniform water supplies under the specific, greatly varying load conditions in the Gulf countries. Such design concepts for hybrid configurations encompass straightforward structures with a low degree of coupling between membrane and thermal desalination processes, but range up to very complex configurations with strong interconnections on both the water side and thermally, as well as with several desalination processes connected in series or in parallel. Classical hybrid concepts in which the permeate from an RO desalination component is mixed with distillate from thermal desalination have already been implemented in Saudi Arabian dual-purpose plants, like Jeddah and Yanbu-Medina. Although hybrid systems of greater complexity have been addressed in many design studies and publications, up to now none has been brought to fruition. Coming into consideration asthe design basis for determining the capacity shares of the various desalination processes operated in a hybrid configuration are: arrangement of thermal cycle of the power plant component; water/power ratio of the dual-purpose seawater desalination and power plant; provision of undiminished water production of the desalination plant as electricity generation varies; provision of a specified drinking water quality with regard to composition and salt content; combination of all these aspects. Also gaining in importance are concerns of environmental pollution and sustainable development when selecting seawater desalination and power plant configurations, as well as their optimization when considering desalination and electricity generation as a whole. In the practical design of hybrid membrane and thermal systems, aspects come to light, though, that restrict linking of the two systems and joint utilization of facilities, as conceived in studies and conceptual design investigations. This applies both for common utilization of intakes and the use of heated up cooling water from thermal processes as a feed stream for the RO part of the desalination process. Additionally, requirements of drinking water composition, particularly chloride content, TDS and compliance with a specific residual content of boron, influence specifically the design of the membrane process part and its share in the total desalination capacity. Such practical aspects have greatly influenced the design and configuration of the Fujairah hybrid plant for which, from a total desalination capacity of 100 MIGD (454,600 m3/d), the share of 37.5 MIGD (170,500 m3/d) makes its seawater RO plant the biggest currently being constructed anywhere in the world. From the findings of the engineering of this plant and the idea that, by increasing interconnection between the two processes on the water side, it is possible to advance a hybrid configuration of this type with regard to cost optimization in the membrane installation, but also by joint utilization of the intake equipment, perspectives result for applied research efforts over the near and long terms, for example: long-term behavior of membranes at elevated temperatures; tendency for biofouling in membrane process with common utilization of cooling water and brine; influences of such interconnections on the overall availability of the facility. But also for the operation and maintenance organization of such large facilities, consequences can be foreseen for the future development of hybrid plants, particularly for operation management and organisation of the interplay of the different power plant and desalination systems, monitoring of SWRO membrane replacement and cleaning, as well as controlling water quality. 相似文献
10.
为适应南水北调信息系统在地域分布特性和各个信息系统本身工程数据多样性的特点,并解决工程管理对数据集成和交换的需求,本文提出面向水利物联网的数据共享平台,依据该平台可以实现南水北调信息系统之间数据共享与交换的稳定性、高效性以及灵活性。 相似文献