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1.
为改善楼阁式古塔建筑夜景照明效果不良的现状,合理优化楼阁式古塔夜景照明色温表现视觉适宜性,在只考虑色温效果视觉呈现的基础上,结合古塔周边夜景照明实际环境特征、古塔照明设计色温应用现状及照明手册色温推荐,开展不同模拟场景下的楼阁式古塔夜景照明色温视觉舒适度主观评价实验,将视觉舒适度评价值作为标签,利用C-SVM支持向量机分类算法构建在不同色温及亮度工况下楼阁式古塔夜景照明色温视觉舒适性主观评价模型,并通过散点图及ROC曲线,对比不同分类模型的分类界面及结果,得到楼阁式古塔建筑最佳色温及亮度表现区间,在不同色温及亮度工况下与视觉舒适度之间的映射关系,进而对楼阁式古塔建筑照明设计色温表现情况进行评价和预测。将C-SVM分类算法与照明领域问题相结合,为设计者更好地利用照明手段还原人们心目中本质的楼阁式古塔建筑特性提供理论依据,改善楼阁式古塔建筑夜景照明效果。  相似文献   

2.
由于金卤(MH)灯和发光二极管(LED灯)作为道路照明光源时,其照明功率密度(LPD)没有标准可依,为此,选取色温为2 000 K的高压钠灯(HPS)、色温为4 800 K的MH灯和色温为7 200 K的LED灯作为照明光源。利用道路照明反应时间测试装置分别进行反应时间实验,得到道路照明亮度水平下MH灯和LED灯相对于HPS灯的亮度对比系数,确定其相对HPS灯的相对光效,并在此基础上计算得到MH灯和LED灯作为道路照明光源时的照明功率密度标准值。研究结果表明:将4 800 K的MH灯作为道路照明光源时,所需LPD为HPS灯的1.3倍左右,将7 200 K的LED灯作为道路照明光源时,所需LPD为HPS灯的47%~89%。  相似文献   

3.
为研究教室照明条件下学生瞳孔大小随亮度水平的变化规律,选择3位大学生作为被试者,采用iView X眼动仪,通过模拟教室照明条件的教室照明瞳孔大小测量系统实验,对3种教室常用色温(2 700 K,4 000 K,6 500 K)荧光灯光源提供的5种背景亮度下的瞳孔面积变化值进行测量.结果显示,3种色温荧光灯下的瞳孔面积与背景亮度呈负指数函数关系;在教室照明条件下人眼瞳孔面积随背景亮度的变大而减小,并逐渐趋于稳定;在相同背景亮度下,色温越高的荧光灯照明时瞳孔面积越小.  相似文献   

4.
目前,各国以及CIE的隧道照明设计规范和标准在隧道照明研究中都只考虑隧道路面的亮度或者照度水平,对于色温、显色性和光谱分布等因素对视觉效果的影响考虑不足,导致对隧道照明质量的评价不够科学。笔者从隧道照明光源光色对于驾驶员视觉功效的影响出发,选择两个隧道进行了小目标识别现场实验和不同色温反应时间测试实验,分析了驾驶员视觉功效受隧道照明光源的显色性和色温的影响情况。结果表明:隧道照明光源显色指数越高,驾驶员的视觉功效越好;对于光谱能量分布相似的光源,背景亮度相同时,含有短波成分多的光源照明效果更好,驾驶员的视觉功效也更好。  相似文献   

5.
光的非视觉生物效应与人体健康密切相关,随着LED在室内照明中的广泛应用,LED照明与人体生理健康的关系也日益重要.心电图(ECG,electrocardiograph)是生理参数的主要表征之一.针对LED照明,以3种色温(3000、5000、6500 K)、5种照度(300、500、750、1000、1500 lx)为主要变量,研究不同光照时长(10、20 min)下,老年人心电指标对光响应的情况.结果显示,照度、色温等光照参数的主效应对老年人的ECG无显著影响,但照度和色温的交互作用对老年人的ECG影响显著.其中,3000 K和10001x的交互作用对P波时间和T波时间影响最大;6500 K和15001x的交互作用影响最小;5000 K和7501x的交互作用对PR间期影响最大,6500 K和5001x的交互作用影响最小.但较短光照时长下,老年人的ECG变化不明显.因此,有必要探讨更长时间(1h及以上)光照下,老年人的心电生理响应情况,从而为老年人健康照明参数的确定提供依据.  相似文献   

6.
石路 《上海交通大学学报》2013,47(10):1616-1620
研究人在不同环境温度下,光源照度和色温对人体体核温度、皮肤平均温度和皮肤血流量的影响,探索光源照明对人体体温调节的作用.对8名受试者在人工气候室不同环境温度(18,30 °C)、光源照度(300,1 000 lx)和色温(3 000,6 000 K)下的体核温度、平均皮肤温度和皮肤血流量进行了60 min的测量和记录.结果表明:无论在高温还是低温条件下,当人体暴露于低色温光源下时人的体核温度较高色温光源下时高;在较低的环境温度下,平均皮肤温度和皮肤血流量在冷色温光源下的值高于低色温光源下的值;在较高温度下,平均皮肤血流量和皮肤温度在低色温光源下的值高于冷色温光源下的值.因此,在环境温度发生变化时,光源照明对人体的热调节起着一定的作用,在环境高温下以运用高色温光源为宜,反之亦然.这提示人们在不同的环境温度下对于光源照度和色温的选择是一个值得重视的问题,除视觉需要外,选择时还应考虑人体生理功能的平衡和舒适感.  相似文献   

7.
本文从色度学的理论出发,阐述了评价照明剂光色的三个特性参数:色坐标、色温或相关色温、显色指数.给出了目前通常使用的四种照明剂的光色特性参数的试验结果.首次报道了中国女性肤色在这四种照明剂光辐射照射下的特殊显色指数.  相似文献   

8.
基于高显色性白光LED的博物馆照明系统设计   总被引:2,自引:0,他引:2  
在详细分析博物馆照明要求的基础上,提出了一种基于白光LED光源的博物馆照明系统解决方案,并进一步实现了低色温、高显色性1 W白光LED的光谱学设计.试验证明,该照明系统解决方案可以满足博物馆内对光比较敏感的参展物品的照明需要.  相似文献   

9.
王津 《科技信息》2010,(4):391-391
对于服装卖场环境的塑造,照明无疑是最为有效的手段,通过人性化的照明设计,能够在短时间内提升卖场的整体艺术气氛,营造出吸引消费者的魅力空间。服装展示照明按其功能通常可分为整体照明、重点照明、气氛照明等照明形式,每种形式都有着不同的功能和特点。展示照明光源的色温对服装色彩的呈现有着很直接的影响。  相似文献   

10.
为了减轻视疲劳,提高工作效率,并尽可能降低建筑的照明能耗,利用主观满意度评价的方法,统计并分析受试者对一般照明、局部照明、混合照明3种照明方式中不同照度与色温组合下光环境满意程度;通过阅读勾销实验测试人员的工作效率;使用闪光融合频率仪测试人在短时暴露下的疲劳度,并对测试结果进行比较,给出相对节能的照明方案.结果表明:高...  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

13.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

14.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

15.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

16.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

17.
正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that  相似文献   

18.
For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the  相似文献   

19.
Franck-Condon factors bridge the gap between theoretical modeling and experimental observations for molecular electronic spectroscopy and electron transfer.Under the displaced harmonic oscillator approximation,multidimensional Franck-Condon factors are decomposed into a product of many one-dimensional(1D)Franck-Condon(FC)factors,and each 1D-FC factor is associated with one Huang-Rhys factor that determines the leading contribution of  相似文献   

20.
<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with  相似文献   

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