人工藻结皮形成过程中表土非降雨型水分吸收的变化情况

在干旱、半干旱地区,表土非降雨型水分吸收对于植物、生物结皮以及一些小型动物都起着非常重要的作用.本研究对库布齐沙漠中各种水分吸收类型进行了调查,并对人工结皮形成过程中水分吸收的变化进行了跟踪监测.结果发现,在实验区,从空气中吸收的水分占表土水分吸收量的25.07%~39.83%,其主要是通过水汽吸附机制进行.相比之下,表土从深层土壤吸收的水分更多,大约占到水分吸收量的60.17%~74.93%.人工结皮的形成促进了表土水分的吸收,但吸收水分的增加并非在接种后或结皮形成后立即表现出来,而是在结皮形成后,结

The single pulse thermal effect mechanism of micro-EDM

为了解微能量单脉冲放电加工原理,文中从微细电火花单脉冲放电加工具有放电时间短,放电通道半径小,能量密度高等特点入手,从单脉冲热作用模型的放电通道半径和能量分配系数方面对当前电火花单脉冲蚀出模型进行改进。建立了时变放电通道的热作用模型,并验证了模型的正确性,提出了单脉冲热作用模型中能量分配到工件表面的百分比系数随着放电参数的变化而变化的规律,为微细电火花的广泛应用奠定基础。The single pulse micro electric discharge machining( micro-EDM) has the characteristics of short discharge time,small discharge channel radius,high energy density,etc. Considering these characteristics,the EDM single pulse erosion model is improved in plasma channel radius and energy distribution coefficient of the single pulse thermal effect model,to establish the thermal effect model of micro-EDM machining. The correctness of the model is verified by a reliable experimental method,which lays a foundation for the wide application of micro-EDM.贵州省教育厅基金项目(5392

DB&IR System: A Survey

介绍了从DB、IR到DB&IR的发展历程；阐述了DB&IR系统的设计考虑因素；讨论了DB&IR系统的体系架构设计问题；介绍了DB&IR系统所采用的基于关键词的查询技术；最后总结并展望未来的研究方向。The development process from DB, IR to DB&IR is presented first, followed by the detailed description of the consideration factors for the design and architecture of DB&IR system. Then keyword search in DB&IR system is discussed. Finally, some future trends in this area are discussed.国家自然科学基金No. 5060401

Design and implementation of the energy management and intelligent monitoring system of a zero energy consumption house

针对2013中国国际太阳能十项全能竞赛比赛规则及零能耗建筑的特点,结合比赛地点山西大同的气候数据,给出了厦门大学参赛作品,零能耗小屋Sunny InSIdE的能源管理与智能监控系统设计方案。以光伏建筑一体化理论为基础,设计15.25kW光伏并网发电系统,并用相关软件对能耗平衡进行了模拟验证。以三菱PlC为核心,构建了能源管理与智能监控系统,分析了不同条件下空调、相变及遮阳系统的控制策略,并给出具体实现方法。According to the rules of the Solar Decathlon China 2013 and the characteristics of zero energy consumption house, combining with the climate data in competition city—Datong Shanxi, an energy management and intelligent monitoring system for the zero energy consumption house called Sunny Inside from Xiamen University was born.A 15.25kW photovoltaic grid connected power system was designed based on building integrated photovoltaic theory, and used relevant simulation software to test energy balance property.An energy management and intelligent monitoring system was constructed based on Mitsubishi PLC, analyzed the control strategy of heating ventilation and air conditioning, phase-change material and shading system under different conditions, and gave a concrete realization method

微重力下板式贮箱内推进剂流动的研究

在卫星平台中,经常用液体推进剂贮箱为其提供能源保障,与其它类型的液体推进剂贮箱相比,第二代表面张力型推进剂贮箱,即板式贮箱,以其显著的性能优势和高可靠的特点成为了很多大型卫星推进剂贮箱的主流。板式贮箱的关键和核心部分是安装和布置在贮箱壳体内部的推进剂管理装置(PMD)。PMD功能的可靠实现,对保证卫星推进系统在空间正常工作具有直接的,决定性的作用和影响。为此,本文将对其进行研究,用三维气液平衡界面计算程序surface evolver对无重力下的板式贮箱中的液体形态进行模拟分析,为以后板式贮箱的设计提供参考