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21.
以西安地区一栋典型办公建筑为例,运用EnergyPlus数值模拟软件研究了相变蓄热通风技术在过渡季节和炎热季节的应用情况。采用日累计降温幅度ΔT和降温潜力百分比J两个指标对其降温效果进行评价,分析了相变材料充分发挥相变潜能时室外干球温度的日气温特征,并基于ASHRAE 55热舒适模型评价了该技术对室内热环境的改善情况。结果表明:当室外干球温度最大值高于相变区间上限值3℃时,最低温度低于相变区间下限值3℃,且日平均温度处于相变区间范围内时,相变蓄热通风技术能够充分发挥相变蓄能作用;该技术在过渡季节的应用效果优于炎热季节,与夜间自然通风技术相比,该技术可使整个过渡季节室内空气温度降温幅度提高14%,室内操作温度满足ASHRAE 55标准的80%,可接受温度范围的小时数提高8%,而整个炎热季节室内空气温度降幅只提高5.6%,室内操作温度满足ASHRAE 55标准的80%,可接受温度范围的小时数仅提高1%。 相似文献
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Maria Angeles Bonmati-Carrion Raquel Arguelles-Prieto Maria Jose Martinez-Madrid Russel Reiter Ruediger Hardeland Maria Angeles Rol Juan Antonio Madrid 《International journal of molecular sciences》2014,15(12):23448-23500
Currently, in developed countries, nights are excessively illuminated (light at night), whereas daytime is mainly spent indoors, and thus people are exposed to much lower light intensities than under natural conditions. In spite of the positive impact of artificial light, we pay a price for the easy access to light during the night: disorganization of our circadian system or chronodisruption (CD), including perturbations in melatonin rhythm. Epidemiological studies show that CD is associated with an increased incidence of diabetes, obesity, heart disease, cognitive and affective impairment, premature aging and some types of cancer. Knowledge of retinal photoreceptors and the discovery of melanopsin in some ganglion cells demonstrate that light intensity, timing and spectrum must be considered to keep the biological clock properly entrained. Importantly, not all wavelengths of light are equally chronodisrupting. Blue light, which is particularly beneficial during the daytime, seems to be more disruptive at night, and induces the strongest melatonin inhibition. Nocturnal blue light exposure is currently increasing, due to the proliferation of energy-efficient lighting (LEDs) and electronic devices. Thus, the development of lighting systems that preserve the melatonin rhythm could reduce the health risks induced by chronodisruption. This review addresses the state of the art regarding the crosstalk between light and the circadian system. 相似文献
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距离选通式半导体激光夜视系统 总被引:1,自引:0,他引:1
距离选通式半导体激光夜视系统是采用高功率脉冲半导体激光器作为夜视系统的照明光源、以微光管作为接收传感器的主动成像夜视系统。介绍了半导体激光夜视系统中所采用的高质量脉冲半导体激光光源技术及距离选通技术。其中光束准直整形技术和改善光场均匀性技术是脉冲半导体激光夜视系统的关键技术。距离选通式激光夜视系统消除了脉冲激光带来的后向散射及杂散光的干扰,提高了接收信噪比,可获取清晰的夜视图像。实验证明采用距离选通式半导体激光夜视系统可在很差的气象条件下工作,并可获得清晰图像,作用距离达5 km。该系统不仅用于军事领域也可用于边防、公安、搜救、监控等其他领域。 相似文献
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实验室条件下微光环境模拟 总被引:3,自引:0,他引:3
从光谱和光度两个方面分析了微光夜视系统的实际工作环境,设计了照度连续可调的微光光源,利用稳流电源供电,实现了实验室条件下的夜天光模拟。经标定,该微光光源的不均匀性小于1%。 相似文献
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哈尔滨地区办公建筑夜间机械通风能耗及室内热环境分析 总被引:2,自引:0,他引:2
采用EnergyPlus软件对哈尔滨地区典型办公建筑在常规空调系统运行模式与夜间机械通风系统运行模式下的室内热环境和能耗进行了模拟。结果表明,在哈尔滨地区,白天室外最高温度高于24℃时都适合进行夜间机械通风,一共约60d,占空调运行期的72.3%;整个夏季空调运行期内,采用夜间机械通风系统该办公建筑节电量指标为1.15kWh/(m2.a),节省运行费用指标为1.02元/(m2.a);在人工制冷阶段,夜间机械通风模式下的室内热环境明显优于常规空调模式,且房间体积与表面积比越小,越有利于提高室内环境的热舒适性;当室内空气设计温度较高时,室内温度下降大,延迟人工制冷开启时间长,但是节能量未必比室内设计温度较低时高。 相似文献
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M.C. Maccarone O. CatalanoS. Giarrusso G. La RosaA. Segreto G. AgnettaB. Biondo A. ManganoF. Russo S. Billotta 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》2011,659(1):569-578
UVscope is a portable multi-pixels photon detector developed at IASF-Pa to support experimental activities in the high-energy astrophysics and cosmic rays field. The instrument, working in single photon counting mode, is designed to directly measure light flux in the wavelengths range 300-650 nm. Thanks to its features and operational flexibility, the instrument can be used in a wide field of applications where the knowledge of the environmental luminosity is required, as in the characterization of sites for ground-based Cherenkov and fluorescence telescopes, and for cross-calibration of their cameras.The present version of UVscope is based on a Multi Anode Photo Multiplier Tube and it is completed by a motorized mount and a filter wheel which allow to make low-light measurements, at programmed pointing directions and at different filter wavelengths. In this paper, the instrument is firstly presented in all its components; then the procedures adopted for its absolute and relative calibration are detailed. The performance of UVscope is evaluated and, finally, current and planned scientific applications are described. 相似文献