通信系统中数字上变频技术的研究与设计

为了将通信系统中数字基带信号调制到中频信号上,采用数字上变频技术,通过对数字I、Q两路基带信号进行FIR成形滤波、半带插值滤波、数字混频处理得到正交调制后的中频信号,最后经MATLAB仿真分析得到相应的时域和频域图,来验证电路设计的有效性。     

SO2 emission characteristics and BP neural networks prediction in MSW/coal co-fired fluidized beds

The SO₂ emission characteristics of typical MSW components and their mixtures have been investigated in a Φ150mm fluidized bed. Some influencing factors of SO₂ emission in MSW fluidized bed incinerator were found out in this study. The SO₂ emission is increasing with the growth of the bed temperature, and it is rising with the increasing oxygen concentration at furnace exit. When the weight percentage of auxiliary coal is being raised, the conversion rate of S to SO₂ is largely going up. The SO₂ emission decreases if the desulfurizing agent (CaCO₃) is added during the incineration process, but the desulfurizing efficiency is weakened with the enhancement of the bed temperature. The fuel moisture content has a slight effect on the SO₂ emission. Based on these experimental results, a 12×6×1 three-layer BP neural networks prediction model of SO₂ emission in MSW/coal co-fired fluidized bed incinerator was built. The prediction results of this model give good agreement with the experimental results, which indicates that the model has relatively high accuracy and good generalization ability. It was found that BP neural network is an effectual method used to predict the SO₂ emission of MSW/coal co-fired fluidized bed incinerator.     

样板扩缩

以23码尖头圆口女鞋为例,在帮样设计后,利用射线扩缩法,采用手工的方式,将基准样板按一定的比例扩缩,形成一系列的成套样板。     

光导管照明系统设计及工程应用

从天然采光的理念着手,介绍了光导管照明系统的概念,对系统中各部件的构成作了简要说明,并对光导管系统与传统照明的节能进行了分析比较。结合某工程现场要求,提出光导管照明系统设计思路和方案,并实际投入应用,随后对不同时段及不同天气条件下光导管照明效果进行测评及分析。结合工程实际状况及局限性,对工程上光导管系统设计及广泛应用提出建议,以期为同行提供参考。     

上海质子重离子医院工艺冷却水及空调水系统节能设计

介绍了该工程的工艺冷却水系统及空调水系统设计中采用的多项节能措施,主要包括工艺一、二次水系统的优化和控制方式以及空调水系统中采用的水源热泵、冷却塔免费供冷等技术手段。     

上海某天象馆空调设计简介

简要介绍了某现代化天象馆的组成;详细描述了天象馆空调系统、排烟系统设计以及需要注意的事项,以供设计参考。     

历史保护建筑改建工程中多联空调系统的运用

分析了暖通设计中如何找到历史保护建筑改建工程“修旧如旧”[1]与“满足建筑使用功能及保证人员舒适度”的最佳平衡点,并结合实际工程介绍了多联空调系统在历史保护建筑中的运用.从“空调系统冷热源的选择”与“空调末端系统的选择”两方面对此进行深入分析,说明了多联空调系统在历史保护建筑改建过程中的优势.     

Degradation of the Tensile Properties of an Au-Coated 316L Stainless Steel Bipolar Plate in a Fuel Cell Stack

Cost reduction for fuel cell stainless steel bipolar plate (BPP)’s Au-coating requires in depth understanding of its corrosion behavior. To this end, this paper explores the degradation of the tensile properties of an Au-coated 316L stainless steel bipolar plate in a real fuel cell stack. 4 BPPs were randomly chosen and removed from a stack that had run for 1600 h and, along with 2 pristine BPPs, were subsequently tested for surface morphology and tensile properties. Results suggest that (1) Pristine BPPs have initial pinhole flaws on the surface, whereas corroded BPPs have punctate (on O₂ side) and continual (on H₂ side) corrosions. (2) The tensile ultimate elongation for a BPP significantly decreases after corrosion on both O₂ and H₂ sides. (3) The degradation of tensile properties is attributed to primary cell effect.

     

金茂三亚度假大酒店一期、二期电气设计比较

比较了金茂三亚度假大酒店一、二期两个五星级酒店建筑的电气设计,包括以下几方面内容：①变电所位置的确定;②电能管理系统的设置;③酒店标准客房的配电箱系统;④二期在客房中增加重要负荷进线的原因;⑤客房管理系统的优势及其在实际应用中的问题等。     

区域医疗健康平台中检验检查指标的标准化算法

由于没有完整可用的指标同义词库以进行指标映射,各家医院关于同一检验检查指标的不同称谓,已严重影响到了区域间医疗信息的互联共享,因而需要对检验检查指标进行标准化处理.这可以看作是一个实体对齐问题,但指标只有相应的取值和取值范围,难以像知识库实例匹配那般使用到属性信息,也不似实体链接那般拥有上下文信息,而且不存在一个标准知识库来提供所有指标的标准名称.针对以上问题,提出指标标准化算法,先根据指标字面特征进行聚类,再使用相似度特征和分块打分特征迭代地进行二分类映射.实验表明,最终的二分类映射,其F1-score可以达到85.27%,证明了该方法的有效性.