作者：徐博林、杜媛媛、陈神飞、杨松柏、李纬晟、张兵、李田茵、赵海天(深圳大学建筑与城市规划学院)

　　我们基于低位道路照明研究了一种新的方法来增强雾的能见度。

　　实验装置：如图所示，该实验是在长度为1.5米*宽度为1.2米*高度为4.0米的密封装置中进行的，根据准确比例1:15模拟了一条长度为60米，三车道宽度为3.75米，紧急车道宽度为3.0米的高速公路。

　　我们使用亮度成像仪记录目标的亮度，汽车照明由两个LED聚光灯模拟。照度计收集聚光灯的照度值。低位路灯设置在两侧40厘米的距离内，以模拟路灯。目标1距离亮度成像仪1.5米，目标2距离亮度成像仪3.0米。聚光灯和照度计用于计算雾浓度。实验装置的所有控制电源均通过无线控制终端进行集中远程控制。

　　实验过程：

　　在无雾情况下，即相对雾浓度为0时，采用机动车照明和低位照明时的两种照明环境下，机动车照明环境优于低位照明环境。然后，我们向装置内加雾。在此过程中，切换两种照明形式，我们很容易发现使用汽车照明会引起强烈的白墙效果。

　　当雾浓度为1时，雾浓度最高，使用汽车照明会产生严重的“白墙现象”，在两种照明条件下都无法确定目标。

　　最后，停止加雾，随着雾浓度降低，低位道路照明先于汽车照明确定目标1。

　　雾浓度为0.957时，随着雾浓度的降低，在汽车照明中只能观察到目标1，而在低位置道路照明中能观察到目标2，并且在低位道路照明中可以观察到目标2的亮度对比度比汽车照明中的目标1高。这也表明，与汽车照明相比，采用低位道路照明可以将可见度从1.5米提高到3.0米。

　　雾气浓度为0.594时，随着雾气浓度一定程度的降低，白墙现象消失，汽车照明中目标1的识别效果优于低位道路照明。对于近距离目标1，汽车照明的亮度对比度值高于低位道路照明的亮度对比度值。但是对于较远的目标2，低位道路照明比汽车照明要好。

　　实验结论：在浓雾天气下，低位道路照明比汽车照明将裸眼能见度增加一倍以上。

　　AMethod to Enhance Visibility in Fog

　　We develop a new method toenhance visibility in fog based on low-position road lighting.

　　Asis shown in the picture The experiment is conducted in a hermetic equipmentthat is 1.5 meters in length*1.2 meters in width*4.0 meters in height,simulating the highway which is 60 meters in length, 3.75 meters in width by 3lanes and 3.0 meters in width by an emergency lane according to the accurateratio of 1:15.

　　We use luminance imager to recordthe luminance of the targets, Automotive lighting is simulated by two LEDspotlights. The illuminometer collects the illuminance value of the spotlight.The low-position road lights are set in the distance of 40 centimeters on bothsides for simulating road lighting. Target 1 is 1.5 meters away from luminanceimager and Target 2 is 3.0 meters away from luminance imager. Spotlight andilluminometer is used to calculate the fog concentration. All control powersupplies of the experimental device adopted centralized remote control by awireless Control Terminal.

　　1、Next, start the experiment. Whenthere is no fog, that is to say, the relative fog concentration is 0, theenvironment under automotive lighting is better than that under low-positionlighting when adopting the two illuminating forms.

　　Then, we fill the device withfog. In this process, switching the two illuminating forms, we easily find thatusing automotive lighting will cause a strong white wall effect.

　　2、When the fog concentration is 1,the fog concentration is the highest, and using automotive lighting wouldproduce a serious "white wall phenomenon", targetsin both lighting conditions can’t be identified.

　　3、Finally, stop generating fog, asfog concentration decreases, target 1 is identified in low-position roadlighting preceding automotive lighting.

　　4、Whenthe fog concentration is 0.957, as fog concentrationdecreases, only the target 1 can be observed in automotive lighting while thetarget 2 can be observed in low-position road lighting, and the luminancecontrast of target 2 in low-position road lighting is higher than that oftarget 1 in automotive lighting. This also indicates that, compared withautomotive lighting, the visibility can be increased from 1.5 meters to 3.0meters by adopting low-position road lighting.

　　5、When the fog concentration is0.594, as fog concentration decreases by a certain extent, the white wallphenomenon disappears and the identification of target 1 in automotive lightingis better than that of low-position road lighting.For close-range target 1, the luminance contrast value of automotive lightingis higher than that of low-positionroad lighting. But for distant target 2, that low-position roadlighting is better than automotive lighting.