scholarly journals Study on the Influence of LED Spectrum on the Visual and Nonvisual Effects in the Interior Zone of Tunnels

2021 ◽  
Vol 2021 ◽  
pp. 1-16
Author(s):  
Li-Li Dong ◽  
Peng Liu ◽  
Qi Lou ◽  
Wen-Hai Xu

Judicious use of lamps is of profound significance to improve the internal traffic safety of tunnels. This study evaluated the biological effects of spectrum on human visual and nonvisual under mesopic vision category. According to the difference of human eyes’ response to the visual and nonvisual biological effects of different wavelengths of light radiation, a method of applying the mesopic visual spectral luminous efficiency curve to the assessment of nonvisual biological effects and blue light hazards is proposed. The results show that, in theory, under mesopic vision category, the spectrum with high correlation color temperature (CCT) and high color rendering index (CRI) has higher blue light content Z-value and has greater impact on human nonvisual effects and blue light radiation damage, but it can also provide higher human perception luminance. The visual effect detection experiment of driving in the interior zones of the tunnel is simulated in the laboratory, and the critical flicker frequency and reaction time are taken as physiological indexes. The results show that the spectrum with high CCT and high CRI corresponds to lower critical flicker frequency drop value and faster reaction time, which has a positive effect on improving driving safety. Therefore, this paper suggests that the LED with high CCT and high CRI (CCT = 6500 K, CRI2012 = 95) should be used in the interior zones of the tunnel with relatively short lighting section, and the CCT and CRI should be appropriately reduced in other road environments with long lighting section to reduce the impact of spectrum on nonvisual photobiology, so as to improve road traffic safety.

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Lei Lin ◽  
Feng Shi ◽  
Weizi Li

AbstractCOVID-19 has affected every sector of our society, among which human mobility is taking a dramatic change due to quarantine and social distancing. We investigate the impact of the pandemic and subsequent mobility changes on road traffic safety. Using traffic accident data from the city of Los Angeles and New York City, we find that the impact is not merely a blunt reduction in traffic and accidents; rather, (1) the proportion of accidents unexpectedly increases for “Hispanic” and “Male” groups; (2) the “hot spots” of accidents have shifted in both time and space and are likely moved from higher-income areas (e.g., Hollywood and Lower Manhattan) to lower-income areas (e.g., southern LA and southern Brooklyn); (3) the severity level of accidents decreases with the number of accidents regardless of transportation modes. Understanding those variations of traffic accidents not only sheds a light on the heterogeneous impact of COVID-19 across demographic and geographic factors, but also helps policymakers and planners design more effective safety policies and interventions during critical conditions such as the pandemic.


Nutrients ◽  
2018 ◽  
Vol 10 (8) ◽  
pp. 1058 ◽  
Author(s):  
Yuji Morita ◽  
Kenta Jounai ◽  
Mika Miyake ◽  
Masaharu Inaba ◽  
Osamu Kanauchi

Background: Visual display terminals (VDTs) emitting blue light can cause ocular disorders including eye fatigue. Some dietary constituents have been reported to be effective in improving ocular disorders while few clinical studies have been performed. We evaluated the effects of heat-killed Lactobacillus paracasei KW 3110 on improving ocular disorders and symptoms of eye fatigue among healthy human subjects with VDT loads. Methods: In vitro, the effect of L. paracasei KW3110 on blue light-induced human retinal pigment epithelial (ARPE-19) cell damage. For clinical studies, 62 healthy Japanese volunteers of 35 to 45 years of age who had experienced eye fatigue were randomized into two groups and given a placebo or L. paracasei KW3110-containing supplements for eight weeks. The primary endpoint was changes in VDT load-induced eye fatigue as determined by critical flicker frequency four and eight weeks after the start of supplementation. Results: In vitro, blue light-induced human retinal cell death was suppressed with the culture supernatants of cells treated with L. paracasei KW3110. In clinical study, the VDT load-induced reduction of critical flicker frequency tended to be milder in the L. paracasei KW3110 group when compared with the placebo group during the fourth week. Subgroup analysis classified by the degree of eye fatigue showed that the VDT load-induced reduction of critical flicker frequency was significantly better in the high-level eye fatigue subjects from the L. paracasei KW3110 group when compared with the placebo group during the fourth week (p = 0.020). Conclusions: L. paracasei KW3110 suppressed blue light-induced retinal pigment epithelial cell death. In the clinical study, ingestion of L. paracasei KW3110 had a potential to improve eye fatigue induced by VDT loads especially high levels of eye fatigue. However, further studies should be required to show more dependable clinical efficacy of L. paracasei KW3110.


2018 ◽  
Vol 56 (05) ◽  
pp. 461-468 ◽  
Author(s):  
Robin Greinert ◽  
Cristina Ripoll ◽  
Alexander Zipprich

Abstract Background and aims Covert hepatic encephalopathy impairs many aspects of quality of life, although its impact on the emotional state has not been evaluated. This study aims to evaluate the impact of covert hepatic encephalopathy on the emotional state and which factors are associated with changes in the emotional state in patients with cirrhosis. Methods This single-center study included all patients with cirrhosis who underwent the portosystemic encephalopathy syndrome (PSE) test, critical flicker frequency, and emotional state assessment with the Eigenschaftswörterliste 60-S in 2011. Covert hepatic encephalopathy was defined by abnormal PSE. Parametric and non-parametric tests were used according to variable distribution. Results One hundred seventeen patients with cirrhosis were included (median age: 59 [interquartile range: 48 – 67], 32 % female, 74 % alcohol-associated). Seventy patients had covert hepatic encephalopathy (60 %) with a higher MELD (16 [interquartile range: 13 – 21], p = 0.001) and a higher Child-Pugh score (p = 0.003) compared to patients without encephalopathy. Patients with covert encephalopathy felt reduced mental activity (p = 0.004), lower general well-being (p = 0.001), and reduced extraversion (p = 0.021). The scores in the negative domains such as general lethargy (p = 0.031) and anxiousness/depressiveness (p = 0.033) were higher in patients with covert hepatic encephalopathy. There was no correlation between MELD and the emotional state. Patients with 2 pathological tests (critical flicker frequency and PSE) showed the most distinct alterations in the emotional state in the group of patients with covert hepatic encephalopathy. Conclusions Patients with covert hepatic encephalopathy have an alteration of the emotional state, which is more marked in patients with 2 pathological tests. Interestingly, MELD had no impact on the emotional state.


2010 ◽  
Vol 13 (1) ◽  
pp. 221-234
Author(s):  
Wojciech Kustra ◽  
Kazimierz Jamroz

Analysis of Factors Influencing the Density of Fatalities on National Roads in PolandIn Poland 20% of the total number of accidents occur on the national roads, which constitute 7% of the length of all roads. In the case of fatalities this share is significantly higher as it constitutes up to 36% of the total casualties. In accordance with the EU Directive (Journal of Laws EU L. 319/59) the level of road traffic safety should be raised by targeting investment on the most dangerous road sections. Finding the dependence between road and traffic factors and the number of accidents and casualties of road accidents may be helpful in predicting safety levels and selecting road traffic safety improvement measures. The paper presents the experience of other countries and preliminary tests results of the impact of the selected factors on the density and the number of road accident fatalities on the national roads in Poland.


2021 ◽  
Vol 276 ◽  
pp. 02008
Author(s):  
Peng Liu ◽  
LiLi Dong ◽  
YingQi Jiang

Judicious use of lamps is of profound significance to improve the internal traffic safety of tunnels. This study evaluated the effect of LED color on human visual fatigue under mesopic vision category. According to the difference of human eyes’ response to different wavelengths of light radiation, the mesopic vision spectral luminous efficiency curve is applied to the visual fatigue evaluation methods. Taking the critical fusion frequency as the physiological index, the detection experiment of human visual fatigue was carried out in the simulated tunnel environment. The results show that spectrum with high color rendering index has a positive effect on alleviating drivers’ visual fatigue, and is more suitable for tunnel interior lighting.


Author(s):  
Monika Stoma ◽  
Jacek Caban ◽  
Agnieszka Dudziak ◽  
Andrzej Kuranc

The article is an attempt to present the two modern concepts of safety management systems. The first is the sunflower pyramid used especially in Europe, the second is the ISO 39001 standard (Road Safety Management System) of international scope. The idea and possibilities offered by use of both concepts of safety management, as well as an attempt to assess the impact of their actions on decrease in fatalities in selected EU countries, were presented. As a result of the conducted analyses, a downward trend was noted as to the number of certificates issued for compliance with the ISO 39001 standard in the world, which may indicate an appearance of the more adequate management systems, or other tools or concepts to improve the road safety, or inadequate education society and low level of awareness in this area of stakeholders, including politicians, scientists, producers, drivers (professional and reliable), as well as other road users, including unprotected ones.


2018 ◽  
Vol 231 ◽  
pp. 05003 ◽  
Author(s):  
Arkadiusz Matysiak ◽  
Paula Razin

The article presents the analysis of the performance of the vehicles equipped with automated driving systems (ADS) which were tested in real-life road conditions from 2015 to 2017 in the state of California. It aims at the effort to assess the impact on the road safety the continuous technological advancements in driving automation might have, based on of the first large-scale, real-life test deployments. Vehicle manufacturers and other stakeholders testing the highly automated vehicles in California are obliged to issue yearly reports which provide an insight on the test scale as well as the technology maturity. The so-called 'disengagement reports' highlight the range and number of control takeovers between the ADS and driver, which are made either based on driver's decision or information provided by the vehicle itself. The analysis of these reports allowed to investigate the development made in automated driving technology throughout the years of tests, as well as the direct or indirect influence of the external factors (e.g. various weather conditions) on the ADS performance. The results show that there is still a significant gap in reliability and safety between human drivers and highly automated vehicles which has been yet steadily decreasing due to technology advancements made while driving in the specific infrastructure and traffic conditions of California.


1978 ◽  
Vol 6 (6) ◽  
pp. 430-434 ◽  
Author(s):  
Peter Crome ◽  
Belinda Newman

Eight healthy volunteers received single doses of either mianserin 10 mg, mianserin 20 mg, amitriptyline 25 mg or placebo. Critical flicker frequency, reaction time, digit substitution and addition times were tested up to six hours afterwards. Mianserin 20 mg and amitriptyline 25 mg significantly prolonged reaction time and mianserin 10 mg and 20 mg significantly reduced critical flicker frequency. No other significant effects were found. Patients should be warned of possible sedation when first starting treatment with mianserin.


2020 ◽  
Vol 12 (4) ◽  
pp. 40-51
Author(s):  
Katarzyna Brzozowska-Rup ◽  
Marzena Nowakowska

Abstract Although the occurrence of road accidents and the number of road accident casualties in almost all Polish voivodeships has decreased over the last few years, the rate of this change varies considerably from region to region. To provide a better understanding of such a tendency, panel data regression models are proposed to conduct this pilot research which evaluates the relative performance of Polish regions in terms of their road traffic safety. Panel data are multi-dimensional data which involve measurements over time. In the research, a voivodeship is a unit analysed at a group level, whereas a year is a unit analysed at a time level. A two-way error component regression model has been applied to survey the impact of regressors, the group effects, and time effects on a dependent variable. The analysis has been conducted using data acquired from the Statistics Poland Local Data Bank website, as well as from the General Directorate for National Roads and Motorways. The panel data from 16 regions in Poland and the 2012–2018 period have been investigated. The examined models refer to road traffic safety indices defined based on the following characteristics: the number of road accidents, the number road fatalities, and the number of people injured. The results of all the three models indicate a negative effect as regards the GDP per capita, (car) motorisation rate, the indicator of government expenditure for current maintenance of national roads, and the road length per capita. A positive association has been found between the truck motorisation rate and the indicator of local government expenditure on roads. The impact of the region's urbanisation indicators on road safety is ambiguous as, on the one hand, its increase causes a reduction in the road accident and accident injury indices, but, on the other hand, it produces a rise in the accident fatality index. In the models, the significance of time effects has been identified; a decreasing time trend suggests a general improvement in road safety from year to year. Most of the group effects have turned out to be highly significant. However, the effects differ as regards both the road accident and the accident injury indices in magnitude and direction.


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