基于直线运动机构的大变倍比红外变焦成像系统

针对同时兼顾大范围搜索和精确识别目标的迫切需求,研制了一种大变倍比红外变焦成像系统,设计两片独立运动的变倍镜及一片补偿镜,通过两个变倍镜级联的方式获得大变倍比。结合系统运动镜片多及变焦曲线复杂的特点,采用直线运动机构实现镜片变焦运动,使用集成编码器及螺纹丝杆的直线电机作为驱动。通过有限元仿真开展了系统力学分析,所设计镜片最大位移为3.04×10^-3 mm。成像系统适用于中波红外制冷式640×512焦平面阵列探测器,变倍比达到55倍。实验室成像及外场实景成像的结果表明,系统在焦距由6 mm至330 mm连续变化的过程中成像清晰、像质良好,验证了系统的连续变焦成像性能,该设计合理可靠。研究成果在搜索、跟踪、侦察、监视等方面有广阔的应用前景。     

够了，让我们实践吧！

众多的软件开发过程到底是为我们解决的问题多,还是造成的问题更多?它们是否真的能够为改进团队的工作方式提供深刻的见解和所需的指导?文中对当代软件开发过程所面临的问题做了深刻的分析,并指出为什么我们现在拥有如此多的过程。     

用于机动车尾气检测的NDIR传感器的加权定标方法研究

非分散红外（NDIR）气体传感器是机动车尾气CO和CO2检测系统的核心部件,一般使用定标的方法来计算待测气体的浓度。针对传统定标方法生成的定标曲线在低于CO和CO2满量程10%范围内的拟合优度不能满足实际使用要求的问题,提出了一种基于最小二乘加权拟合法的定标方法,通过对低浓度点赋予更大的权重和增加定标点的数目来改善定标曲线在低浓度范围内的拟合优度。采用该方法的定标结果表明,定标曲线在整个量程范围内的定标误差均小于2%。所提出的定标方法具有较高的应用价值。     

Strategy of water pollution prevention in Taihu Lake and its effects analysis

Taihu Lake, the third largest freshwater lake in China, is located in the Chanjiang Delta of the Yangtze River. Its waters are used by agriculture, industry and as major drinking water for several cities including Shanghai and Wuxi. The lake also is important for tourism, aquaculture and flood control. Taihu Lake and its surrounding areas are facing three major water-related threats: deteriorating water quality with inflow and runoff from its watershed; flooding during the rainy seasons; and water shortages during drier months. Noxious algae blooms are occurring with increasing frequency and water quality continues to decline. Remedial actions implemented to date have been ineffective. This paper proposes that the problems could be remedied by constructing a by-pass channel (BPC), which would divert low-quality water from the lake during low precipitation periods and allow better quality water to flow into the lake during high flow periods. This remedial action would simultaneously deal with the deteriorating water quality of Lake Taihu and maintain its water level at a desired level. A preliminary assessment of this strategy shows that, if the BPC were implemented, the water quality of Taihu Lake would be improved significantly in few years, the flood disaster would be greatly mitigated, and the water shortage problem in the basin would be alleviated.     

海蛇肉罐头生产工艺

<正>我国有漫长的海岸线,沿海一带的海蛇资源十分丰富,海蛇肉是一种营养丰富的海产品,除味道鲜美外,还有祛风、燥湿、通络活血、滋补强壮,使人皮肤光滑、不长疮等药效.据有关文献资料记载:海蛇肉中含有蛋白质13%~15%,脂肪0.21%~0.25%,灰分0.88%~