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大坝安全对于保证社会稳定和有序发展至关重要.介绍了一种基于单片机MSC1210的多功能数据采集模块,该模块为一个分布式大坝安全监测自动化系统的核心部件.该系统主要由监测传感器,数据采集模块及监控主机三部分组成.数据采集模块完成对所连接的各类监测传感输出信号的采集,处理和存储,并实现与监控主机的通信,可检测电压,电流,频率,阻抗等形式的信号,其与监控主机的通信采用RS-485和GPRS无线传输互为备用的方式.重点研究了数据采集模块的工作原理、硬件构成及抗干扰措施。本系统应用了测量及通信技术的最新成果,在准确度、可靠性、扩展性、简易性等方面都有很大的提高。  相似文献   
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为了移动核心网更加安全,在核心网络中推进MSC POOL技术,该技术具有提高设备利用率、节省信令开销、减少局间位置登记、减少局间切换以及提高网络性能等许多方面的优势。  相似文献   
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以某车双横臂独立悬架的下控制臂为研究对象,基于有限元模态分析、多体动力学和疲劳分析等相关理论,综合运用MSC.Nastran,MSC.Adams及MSC.Patran(Fatigue)软件对其进行疲劳寿命集成化虚拟试验仿真研究,在较短的时间内预知该零部件的疲劳寿命和危险部位等信息。研究表明,该方法可以作为汽车设计和试验的有效手段。  相似文献   
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Fucoidans, sulfated polysaccharides extracted from brown algae, are marine products with the potential to modulate bone formation and vascularization processes. The bioactivity and safety of fucoidans are highly associated with their chemical structure, which may vary with algae species and extraction method. Thus, in depth evaluation of fucoidan extracts in terms of endotoxin content, cytotoxicity, and their detailed molecular biological impact on the individual cell types in bone is needed. In this study, we characterized fucoidan extracts from three different Fucus species including Fucus vesiculosus (Fv), Fucus serratus (Fs), and Fucus distichus subsp. evanescens (Fe) for their chemical features, endotoxin content, cytotoxicity, and bioactive effects on human outgrowth endothelial cells (OEC) and human mesenchymal stem cells (MSC) as in vitro models for bone function and vascularization. Extracts contained mainly high molecular weight (HMW) fucoidans and were free of endotoxins that may cause inflammation or influence vascularization. OEC tolerated fucoidan concentrations up to 200 µg/mL, and no indication of cytotoxicity was observed. The inflammatory response, however, investigated by real-time PCR (RT-PCR) and enzyme-linked immunosorbent assay (ELISA) and endothelial barrier assessed by impedance measurement differed for the individual extracts. MSC in comparison with endothelial cells were more sensitive to fucoidans and showed partly reduced metabolic activity and proliferation at higher doses of fucoidans. Further results for MSC indicated impaired osteogenic functions in alkaline phosphatase and calcification assays. All tested extracts consistently lowered important molecular mediators involved in angiogenesis, such a VEGF (vascular endothelial growth factor), ANG-1 (angiopoietin 1), and ANG-2 (angiopoietin 2), as indicated by RT-PCR and ELISA. This was associated with antiangiogenic effects at the functional level using selected extracts in co-culture models to mimic bone vascularization processes during bone regeneration or osteosarcoma.  相似文献   
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隧道衬砌台车有限元结构仿真及优化设计   总被引:1,自引:0,他引:1  
基于有限单元法的基本思想为理论基础,用MSC/PATRAN建立隧道衬砌台车仿真模型,对其在工作状态下的工况进行MSC/NASTRAN强度、刚度分析,得到隧道衬砌台车的最大应力、应变值及分布情况。通过分析,此隧道衬砌台车有进一步优化的空间,接着在MSC/NASTRAN中定义设计变量,确定设计目标,进行优化设计。结果表明用MSC/PATRAN建模分析可以节省人力物力,又有比较高的模拟精度,对于工程实际是相当有帮助的,可以提高工程机械结构设计水平,使得结构更加合理,满足当今机械设计发展的需求,本文的研究方法适用于指导任何其他类型机械的分析。  相似文献   
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高沙土地区土壤含沙量高,渗漏严重,采用混凝土暗渠,可集节约用水、降低成本、复垦土地等诸多优点于一体,是解决该地区农业灌溉缺水的出路之一。通过大型有限元分析软件MSC.MARC从结构角度验证暗渠断面的合理性。  相似文献   
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Approaches to counter the overfishing and aquaculture production crisis include those imposed by public governing bodies, as well as those implemented by businesses and non‐governmental organizations (NGOs). In the case of the latter, private actors govern fisheries consumption and production through corporate social responsibility (CSR). In this contribution, we focus on three key tools that businesses are increasingly turning towards in an effort to meet the one particular CSR goal of sustainable seafood sourcing. In this context, the key tools of certifications, fisheries improvement projects (FIPs) and traceability are reviewed, and their potential as well as limits in contributing to continual improvement in pursuit of global seafood sustainability are analyzed. We argue that seafood CSR has created its own whimsical and fantastical world, a Seussian world, in which company image has become more important than sustainability performance. We posit four important barriers that must be overcome to bring seafood CSR back to reality. Specifically, we suggest moving away from the business case for CSR, reducing accessibility barriers for small‐scale and developing world fisheries, reconciling different labels and sustainability concepts, and better recognizing the imperative role of the state in governing fisheries and seafood.  相似文献   
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