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1.
To obtain the expression of maximum spectral luminous efficiency of mesopic level, we studied the contribution to spectral sensitivity in the mesopic region of the rods and cones based on heterochromatic brightness matching and reaction time, respectively. We next acquitted the expression of maximum spectral luminous efficiency of the mesopic level. Our opinion is that the results based on different experiments reflect different vision characteristics of human beings. The expression of maximum spectral luminous efficiency should be chosen in accordance with the application. We advise that the maximum spectral luminous efficiency based on heterochromatic brightness matching should be chosen in evaluating the effect of night scene lighting. The maximum spectral luminous efficiency based on reaction time should be chosen in designing road lighting.  相似文献   

2.
Five color temperature LEDs were compared to traditional light sources (HPS and MH) under three lighting levels and negative contrasts to study the effect of light sources color on tunnel lighting. Through the experiment of reaction times, the relation between light sources color and reaction times, and the relation between light sources color and pupil size were studied, respectively. The experiment result shows that visual performance and cirtopic with high color temperature LED are the most significant under high lighting level. The visual performance and cirtopic with middle color temperature LED are the most significant under mesopic lighting level. It is shown that comprehensive influence of light sources color on visual performance and cirtopic must be considered for choosing appropriate light sources in different sections of tunnel lighting.  相似文献   

3.
The road lighting system and the road greening system, which are mutually interrelated and independent, are two important parts in the urban road environment. Unreasonable road lighting is easy to induce light pollution and has a great negative impact on the physiology and growth of garden plants in the urban green space. In this paper, 21 kinds of common tree species in the urban green space of Zhengzhou were selected as the research object, and the photosynthetic physiological parameters of landscape trees under the LED light source were observed using LI-6400 Photosynthesis System. This paper attempted to find the critical point for initiating photosynthesis of different types of tree species under a certain light source and then calculated the safe distance between lighting fixtures and landscape trees. The results showed that road lighting interfered with the photosynthetic physiological activities of the surveyed trees, affecting the normal dormancy of the plants at night; the sensitivity of different tree species to night lighting was different, and there were some differences in the light compensation points, so the corresponding safe distance was also different. It is hoped that this study can provide a valuable reference and scientific basis for urban road greening and lighting design.  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.
不同LED照射方式对鸡毛菜货架期品质及活性氧代谢影响   总被引:1,自引:0,他引:1  
为研究不同发光二极管(LED)光照方式对货架期蔬菜的保鲜效果,以小白菜的幼苗毛菜为试材,分析了连续照射、脉冲照射和光刺激3种不同光照方式对鸡毛菜货架期品质的影响。结果表明:黑暗条件下鸡毛菜货架期仅有48 h,并且完全萎蔫黄化,丧失商品性;货架48 h,与黑暗对照相比,3种LED光照方式照射能较好地维持鸡毛菜的硬度、脆度、L*值、a*值和叶绿素含量,抑制失重率的上升,保持鸡毛菜良好的商品性;脉冲照射和连续照射比光刺激能更好地抑制组织相对电导率的上升,减少丙二醛、H2O2和超氧阴离子累积,维持活性氧代谢途径中过氧化物酶(POD)、过氧化氢酶(CAT)、超氧化物歧化酶(SOD)和抗坏血酸过氧化物酶(APX)的活性,且通过感官品质和贮藏品质综合对比发现脉冲照射的保鲜效果更佳。因此,脉冲照射是鸡毛菜货架贮藏的最适LED光照条件。  相似文献   

6.
Through the analysis on components of the environment,the essential factors affecting the city illumination,such as human beings,light and objects,are discussed in this paper with the help of environment psychology.On the basis of people's visual characteristics and psychological needs,the characters of illumination of the city in whole,city square,buildings and garden landscape are summarized and the laws of city illumination are revealed.It is found that designing the city illumination should create not only a visual environment but coordination with city spatial elements and physiological sense of human beings,offering a psychological environment in harmony with function atmosphere.The author finally puts forward his thinking on city illumination which combines the natural condition,object form,people's visual characteristics and environmental features based on the environment principle.  相似文献   

7.
Quality Evaluation Indicators for Urban Sideway Traffic Road Lighting   总被引:1,自引:0,他引:1  
CIE has proposed the semi-cylindrical illuminations as evaluation indicators and the overseas reports nave also been put forward in the use of three-dimensional sense indicators to prevent violations based on the assessment of lighting to create efficient, economic, safe and comfortable urban traffic lighting environments. But this required experimental verifications. The study used subjective and objective experiment methods to survey the parts of the sidewalk lighting in Chongqing urban. Through extensive testing information disposals and analyses, the autrors illumination should be the optimal parameters of sidewalk lighting and exist problems at present. The computer gray separation method is first used in analysing the facial features of pedestrians at night. It gets the scope of applications and application conditions of three-dimensional sense. The study provide an experimental basis and scientific method for constituting sidewalk lighting evaluation indicators, and provided important values for the study of sidewalk lighting evaluation indicators.  相似文献   

8.
光照对植物合成花色素苷的影响研究进展   总被引:1,自引:0,他引:1  
花色素苷决定着花卉、果实及彩叶植物叶片的颜色,对植物的观赏性有着重要价值,已受到人们的广泛关注。近几年来,对于外界环境影响植物花色素苷合成的研究已有相关报道,但都是一些综合性的阐述。对于光照影响植物花色素苷的研究,缺乏更为系统和深入的论述。依据国内外近几年的相关文献,在阐述植物花色素苷合成机理的基础上,针对光照这一外界环境因子,综述了光照时间、不同光质及光照强度对于植物花色素苷合成的影响。指出了对于一般植物,光照时间越长,越有利于其合成花色素苷;在不同的光质中,对合成花色素苷最有效的是蓝光和紫外光;对于一般植物,光照强度越大,越有利于合成花色素苷。还分析了目前关于植物花色素苷研究尚存在的问题,并展望了今后的研究方向,以期为今后的研究提供一些参考。  相似文献   

9.
为探究NaCl胁迫处理对采后马铃薯见光绿变及龙葵素生成的影响,本试验先将马铃薯块茎置于20% NaCl溶液中分别浸泡6 h和12 h,后置于光照条件下进行试验。结果表明:与见光对照相比,2个处理均显著提高了马铃薯的综合感官品质,货架期延长1倍;NaCl溶液处理较好地抑制了马铃薯表皮绿变,在同一光照时间,处理马铃薯表皮a*、叶绿素含量显著低于对照组;8天货架期后,2个处理马铃薯龙葵素含量显著低于见光对照组,8天货架期间,对照龙葵素增加了122%,而NaCl处理6 h和12 h的龙葵素含量分别增加了68.86%和91.42%。因此,20% NaCl处理可有效抑制马铃薯表皮绿变和龙葵素的产生,并且20% NaCl处理对马铃薯发芽也有明显的抑制作用。  相似文献   

10.
This paper probes into visual characters of older people, analyzes circumstance of lighting luminous environment under their living condition and then, beginning with visual physiology and visual psychology, it studies the illuminance and design methods of lighting luminous environment for older people living areas in residence.  相似文献   

11.
储藏条件对马铃薯渣中龙葵素含量影响的研究   总被引:2,自引:0,他引:2  
采用乙醇—乙酸法提取不同储藏条件下马铃薯渣中的龙葵素,通过测定其含量及纯度,研究了光照、储藏温度及储藏时间对马铃薯渣中龙葵素含量的影响。结果表明,马铃薯渣中的龙葵素含量与储藏时间及温度呈正相关,光照条件对龙葵素含量的影响显著。  相似文献   

12.
对大小垄栽培群体和30cm等行距栽培群体不同层次的光照强度、群体行间温、湿度等生态因子及每穴穗数、每穗实粒数和单穴生产力三个产量性状和不同分蘖时期每穴茎数的边际效应指数进行了研究。结果表明,大小垄栽培群体下部的光照强度和透光率显著增加,行间温、湿度降低,使群体内部的光、温条件得到改善。每穴穗数、每穗实粒数和单穴生产力及不同分蘖时期每穴茎数的边际效应指数降低,说明实行大小垄种植后,群体内部的长势与边行的差距缩小,群体内部个体的生长优势得到发挥,达到了利用边际优势增产的目的。  相似文献   

13.
水稻边际优势利用栽培增产的生态原因分析   总被引:7,自引:0,他引:7  
对大小垄栽培群体和30cm等行距栽培群体不同层次的光照强度、群体行间温、湿度等生态因子及每穴穗数、每穗实粒数和单穴生产力三个产量性状和不同分蘖时期每穴茎数的边际效应指数进行了研究。结果表明,大小垄栽培群体下部的光照强度和透光率显著增加,行间温、湿度降低,使群体内部的光、温条件得到改善。每穴穗数、每穗实粒数和单穴生产力及不同分蘖时期每穴茎数的边际效应指数降低,说明实行大小垄种植后,群体内部的长势与边行的差距缩小,群体内部个体的生长优势得到发挥,达到了利用边际优势增产的目的。  相似文献   

14.
In order to establish the relationship between subjective sense and physical measurement in lighting engineering, the qualitative and quantitative analyses are connected through generalized Weber - Fechner Law. For practical application problems of lighting engineering, a proximate function of subjective sense deduced from physical measurement is brought forward. The experiment in advertising lighting shows that the result of this function is more exact and more closely to the practice than others. Using this proximate function, the illumination level, corresponding to given satisfaction level, can be found. In other words, the physical measurement corresponding to given subjective sense can be evaluated by using this proximate function, accordingly the design of lighting project can be directed reasonably.  相似文献   

15.
为研究水稻不同种植模式对稻瘟病发生影响,通过试验设计、采样设计,以稻瘟病病原菌为研究对象。通过定时捕捉稻瘟病病原菌孢子,并与温度、光照强度、相对湿度、不同试验区间进行研究分析。试验结果表明:孢子量变化与温度、光照强度和相对湿度呈正相关;同一种植模式及布局接壤的试验区孢子量变化间呈显著正相关;研究还发现多样性种植的试验区孢子总量略低于单一种植的试验区孢子总量,说明多样性种植能较好地抑制稻瘟病的发生。同时,利用分形理论研究了整个试验区的分形维,研究表明:分形维为小数,说明整个试验区具有一定的混沌特性。  相似文献   

16.
便利店销售额在传统零售业中增幅最高,照明在所调研样本总室内能耗中占比为43%。基于全国257家便利店的数据,探讨便利店的照明特征。采用多重线性回归方法建立照明能耗预测模型,采用因子分析方法探讨客观参数与主观评价的联系。研究表明,对便利店,考虑照明节能时需同步关注其主观评价的变化;进行照明设计时需因地制宜;照明能耗预测模型为ln y=0.479 ln x1+ 0.248ln x2-0.217(y为照明功率密度,x1为单位面积照明造价,x2为典型货架位置水平照度平均值);顾客对照明充足度的“敏感性”比照明均匀度高;提高照度平均值有助于提高主观评价。  相似文献   

17.
The effect of fiber in asphalt mixtures has attracted general concern. For study of this problem, four kinds of fibers are chosen in this test. Asphalt and modified asphalt are adopted in asphalt mixtures AC-16I. The road performance influenced by additional fiber was analyzed impersonally,i, e. the stability of asphalt concrete under high temperature condition, anti-crack ability under low temperature condition, the water resistance and fatigue performance. It was shown through the research that the optimum asphalt content, air void rate, clearance rate of the mineral powder, saturation degree, and the flow value were increased and the density was decreased after adding the fiber. The road performance, such as the stability of asphalt concrete under high temperature condition, anti-crack ability under low temperature condition, water resistance and fatigue performance, was obviously improved,and the high temperature stability and fatigue performance improved most evidently. The fiber asphalt mixture performance reached and even exceeded the modified asphalt mixture performance. The modified asphalt performance after adding fiber would be improved more greatly.  相似文献   

18.
一种室内大量饲养灰飞虱的方法   总被引:1,自引:0,他引:1  
灰飞虱是重要的农业害虫和病毒传播介体,为给相关研究提供足够的活体材料,建立了一种室内灰飞虱规模化饲养的方法,笔者经一系列生物学试验,对温度、光强、饲养密度等条件进行了优化,并对产卵和换苗时间进行了规定。试验表明饲养温度24~28℃,光照强度5000~7000lx,不同龄期虫的饲养密度分别为300~400头/杯(若虫)、200~300头/杯(3~4龄虫)、100~200头/杯(成虫)适合各自饲养时水稻苗的生长、灰飞虱的发育繁殖、卵的孵化等。为保证同批次虫龄的一致性,规定产卵时间和换苗时间分别为48h和8~10天。此方法条件因素明确,可操作性强,不受场地、时间、环境等自然条件限制;可随时提供足量试验用龄次标准试虫。  相似文献   

19.
密闭式植物种苗工厂的设计及其光环境研究   总被引:1,自引:0,他引:1  
密闭式植物苗工厂具有节能、环保、控制精度高、生产成本低等特点,发展前景广阔。利用不透光的绝热材料建设人工光型密闭式植物工厂,设计开发了高精度的环境控制系统,为植物生长提供优化的物理环境。研制了种苗繁育LED光环境调控装置、光照距离可调式荧光灯板,有效地改善植物生长所需的光环境,提高植物的光能利用率。通过对环境控制系统的试验研究以及相关的生物学试验,为密闭式植物工厂以及人工光源在育苗领域的应用研究提供了理论和试验依据。LED、荧光灯与自然光条件下黄瓜育苗对比试验表明LED光环境下植株生长速率高于其他处理,表现出一定的生长优越性。  相似文献   

20.
This paper suggests that using best solar energy and advancing visual performance,a new evaluating method may be put that is about luminous environment.It not only recommends twelve parameters(targets),considering luminous environment and sky light climate but also luminary,heating,lowering temperature,psychology and physiology,ect.in accordance withyear's effect of daylighting.On the basis of different sky lighting climate areas and main uses of buildings.We use with a considerable weight factor that is satisfied with a basic function.Then by fuzzy multiple criterion,the distinct result about luminous environment in buildings is obtaoned.  相似文献   

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