Small-scale fire tests in the underwater tunnel section model with new sidewall smoke extraction

The Shenzhen–Zhongshan Bridge is a 24‐km‐long bridge and tunnel system,including a 6.8-km-long super cross section subsea tunnel.To solve the smoke exhaust problem of a super large cross-section subsea tunnel,the tunnel has a new smoke exhaust system that combines a horizontal smoke exhaust cross section at the top and sidewall smoke exhaust holes.In order to evaluate the potential fire hazards of this type of tunnel,a 1:30 tunnel model was established and 140 smallscale experiments on underwater tunnel fires were conducted.By changing the fire power,fire location,and fan operation mode,different scenarios of submarine immersed tunnel fire were simulated and the related key parameters such as fire smoke diffusion behavior and smoke temperature distribution were studied.On this basis,the optimal smoke control strategy was proposed for different fire scenarios.The research results indicate that the new smoke exhaust system can fully utilize the smoke flow characteristics,significantly improve smoke exhaust efficiency,and increase available evacuation time,thus further enhancing the fire safety of super large cross-section subsea tunnels.

Inhibition of the NF-κB Signaling Pathway Improves Cigarette Mainstream Smoke-Induced Lung Injury and Gut Microbiota Disturbance

Currently,cigarette smoke(CS)remains a major contributor to disease morbidity and mortality.CS can be divided into cigarette mainstream smoke(CMS)and side-stream smoke,depending on where it is produced by burning tobacco^([1]).CMS is inhaled by smokers from the filter end during cigarette combustion and is strongly associated with the development of several diseases^([2-4]).

U-Net Inspired Deep Neural Network-Based Smoke Plume Detection in Satellite Images

Industrial activities, through the human-induced release of Green House Gas (GHG) emissions, have beenidentified as the primary cause of global warming. Accurate and quantitative monitoring of these emissions isessential for a comprehensive understanding of their impact on the Earth’s climate and for effectively enforcingemission regulations at a large scale. This work examines the feasibility of detecting and quantifying industrialsmoke plumes using freely accessible geo-satellite imagery. The existing systemhas so many lagging factors such aslimitations in accuracy, robustness, and efficiency and these factors hinder the effectiveness in supporting timelyresponse to industrial fires. In this work, the utilization of grayscale images is done instead of traditional colorimages for smoke plume detection. The dataset was trained through a ResNet-50 model for classification and aU-Net model for segmentation. The dataset consists of images gathered by European Space Agency’s Sentinel-2 satellite constellation from a selection of industrial sites. The acquired images predominantly capture scenesof industrial locations, some of which exhibit active smoke plume emissions. The performance of the abovementionedtechniques and models is represented by their accuracy and IOU (Intersection-over-Union) metric.The images are first trained on the basic RGB images where their respective classification using the ResNet-50model results in an accuracy of 94.4% and segmentation using the U-Net Model with an IOU metric of 0.5 andaccuracy of 94% which leads to the detection of exact patches where the smoke plume has occurred. This work hastrained the classification model on grayscale images achieving a good increase in accuracy of 96.4%.

An Improved YOLOv5s-Based Smoke Detection System for Outdoor Parking Lots

In the rapidly evolving urban landscape,outdoor parking lots have become an indispensable part of the city’s transportation system.The growth of parking lots has raised the likelihood of spontaneous vehicle combus-tion,a significant safety hazard,making smoke detection an essential preventative step.However,the complex environment of outdoor parking lots presents additional challenges for smoke detection,which necessitates the development of more advanced and reliable smoke detection technologies.This paper addresses this concern and presents a novel smoke detection technique designed for the demanding environment of outdoor parking lots.First,we develop a novel dataset to fill the gap,as there is a lack of publicly available data.This dataset encompasses a wide range of smoke and fire scenarios,enhanced with data augmentation to ensure robustness against diverse outdoor conditions.Second,we utilize an optimized YOLOv5s model,integrated with the Squeeze-and-Excitation Network(SENet)attention mechanism,to significantly improve detection accuracy while maintaining real-time processing capabilities.Third,this paper implements an outdoor smoke detection system that is capable of accurately localizing and alerting in real time,enhancing the effectiveness and reliability of emergency response.Experiments show that the system has a high accuracy in terms of detecting smoke incidents in outdoor scenarios.

Pursuing a smoke-free generation

The United Kingdom may soon become a world leader in forging a smoke-free generation.Last month,the country passed a bill that bans the sale of cigarettes to anyone born in 2009 or later.The prime minister claims the policy will"phase out smoking in young people almost completely as early as 2040."A final vote by Parliament is expected next month.Tobacco claims 8 million lives every year,and could claim a billion lives over this century-mostly in low-and middle-income countries.For every person that dies,at least 30 more suffer from smokingrelated chronic disease.The benefits of a tobacco-free society would be transformational.

Impact of Smoke-Free Legislation on Acute Myocardial Infarction and Subtypes of Stroke Incidence in Shenzhen,China,2012-2016:An Interrupted Time Series Analysis

Objective This study assesses the impact of smoke-free legislation on the incidence rate for acute myocardial infarction(AMI)and stroke in Shenzhen.Methods Data on ischemic(n=72,945)and hemorrhagic(n=18,659)stroke and AMI(n=17,431)incidence covering about 12 million people in Shenzhen from 2012 to 2016 were used.Immediate and gradual changes in incidence rates were analyzed using segmented Poisson regression.Results Following the smoke-free legislation,a 9%(95%CI:3%-15%)immediate reduction was observed in AMI incidence,especially in men(8%,95%CI:1%-14%)and in those aged 65 years and older(17%,95%CI:9%-25%).The gradual annual benefits were observed only in hemorrhagic and ischemic stroke incidence,with a 7%(95%CI:2%-11%)and 6%(95%CI:4%-8%)decrease per year,respectively.This health effect extended gradually to the 50-64 age group.In addition,neither the immediate nor gradual decrease in stroke and AMI incidence rates did not show statistical significance among the 35-49 age group(P>0.05).Conclusion Smoke-free legislation was enforced well in Shenzhen,which would generate good experiences for other cities to enact and enforce smoke-free laws.This study also provided more evidence of the health benefits of smoke-free laws on stroke and AMI.

基于WRF-SMOKE-CMAQ模型的济南市清洁取暖改造环境效益评估

为评估济南市清洁取暖改造后的环境效益,以2018年为基准年,采用WRF-SMOKE-CMAQ模型模拟计算了2019—2021年济南市冬季清洁取暖改造后各项污染物改善率,并分析了不同污染时段和不同气象条件下污染物的改善率。结果表明:济南市清洁取暖改造后各污染物浓度均有不同程度的改善,其中CO、SO_(2)和细颗粒物(PM_(2.5))基准年改善率(模拟的污染物浓度相对于基准年同时段的改善率)较大,主要与散煤燃烧CO、SO_(2)和PM_(2.5)的排放因子较大有关,2020年年均改善率(模拟的污染物浓度相对于去年同时段的改善率)最大,主要与污染物的减排量最多有关;各污染物改善呈现出明显的区域差异,清洁取暖改造户数较多的区县污染物年均改善率较高;各污染物在空气严重污染时段基准年改善率均最大,重度污染时段次之,并且在不利气象条件时基准年改善率也最大,说明清洁取暖改造对冬季不利气象条件造成的高污染物浓度起到明显的削峰作用,可为济南市空气质量持续改善提供有力保障。

The Association between Exposure to Second-Hand Smoke and Disease in the Chinese Population: A Systematic Review and Meta-Analysis

Objective To analyze the association between exposure to second-hand smoke(SHS) and 23 diseases,categorized into four classifications, among the Chinese population.Methods We searched the literature up to June 30, 2021, and eligible studies were identified according to the PECOS format: Participants and Competitors(Chinese population), Exposure(SHS),Outcomes(Disease or Death), and Study design(Case-control or Cohort).Results In total, 53 studies were selected. The odds ratio(OR) for all types of cancer was 1.79(1.56–2.05), and for individual cancers was 1.92(1.42–2.59) for lung cancer, 1.57(1.40–1.76) for breast cancer, 1.52(1.12–2.05) for bladder cancer, and 1.37(1.08–1.73) for liver cancer. The OR for circulatory system diseases was 1.92(1.29–2.85), with a value of 2.29(1.26–4.159) for stroke. The OR of respiratory system diseases was 1.76(1.13–2.74), with a value of 1.82(1.07–3.11) for childhood asthma. The original ORs were also shown for other diseases. Subgroup analyses were performed for lung and breast cancer. The ORs varied according to time period and were significant during exposure in the household;For lung cancer, the OR was significant in women.Conclusion The effect of SHS exposure in China was similar to that in Western countries, but its definition and characterization require further clarification. Studies on the association between SHS exposure and certain diseases with high incidence rates are insufficient.

Design and Optimization of New Smoke Exhaust Pipe for Mining Trucks

In order to improve the maintenance efficiency,extend the use time,ensure that the exhaust emission meets the standard,forthe 830E truck heating bucket exhaust pipe design defects,the current single smoke exhaust system is transformed into atime period,convertible smoke exhaust system.After the transformation,it can not only realize the side row to prevent direct corrosion of the box bucket in summer,but also realize the heating of the box bucket at low temperature in winter to prevent snow and ice and frozen blocks from sticking to the box bucket and the materials transported.After the transformation can save a lot of manpower,material resources,financial resources,improve the service life.

Smoke Hazard Assessment Model Based on Fire Dynamics Simulator and FED Model

Smoke is the main cause of fire death. In order to minimize the potential danger of smoke hazard, a rational VR based fire training simulator should fully consider all aspects of smoke hazard. In the simulator, the visualization of data based on FDS (Fire Dynamics Simulator) and FED fire dynamic data and volume rendering is further optimized, which can be effectively and quickly applied to virtual fire protection. In addition, a comprehensive smoke hazard assessment model based on FED and FED is established to assess the IHD value of different paths, which represents the safety of different paths, and can be used for evacuation or rescue in virtual training. Taking the case of campus fire drill as an experiment, the research shows the accuracy and effectiveness of smoke assessment based on FDS and FED model. The road force with the highest safety can be selected through the comprehensive model. So the assessment model is proved to be valuable.

Carbon Monoxide and Respiratory Disorders in Professional Female Fish Smokers at 2 Artisanal Sites in Benin

Introduction: The use of biomass for cooking is a very common practice in Africa and Benin, and is associated with exposure to organic pollutants. The aim of this study was to assess carbon monoxide exposure and respiratory disorders in women at artisanal fish-smoking sites. Methods: This was a cross-sectional study of women fish smokers at two artisanal fish-smoking sites in Benin. Recruitment was exhaustive. An interview using a respiratory questionnaire inspired by the Union questionnaire, spirometry and carbon monoxide (CO) measurement were carried out. Descriptive analysis and comparison of means using Student’s t-test with a threshold of p = 0.05 were performed. Results: The median age of the 81 people surveyed was 40, with an interquartile range (IQT) of [25 to 75]. The median duration of daily exposure to smoke was 6 h IQT [4, 7]. Of those surveyed, 64 (79.01%) were illiterate and 39 (48.24%) had been working for 20 years. CO levels at the start of activity varied from 89 to 145 ppm in one case and from 40 to 89 ppm in the other. Respiratory symptoms were present in 19 (23.46%);18 (22.22%) had mild airway impairment on spirometry. There was a statistically significant decrease between the mean values of peak expiratory flow (PEF), mean expiratory volume in seconds (FEV1) and forced vital capacity (FVC) before and after exposure to smoke. Conclusion: CO levels are high on fish smoking sites and respiratory problems are common. Improved working conditions are important for these women.

Analysis of temporal and spatial distribution characteristics of ammonium chloride smoke particles in confined spaces

In response to the demand for short-range detection of anti-smoke environment interference by laser fuzes,this study proposes a smoke environment simulation of non-uniform continuous point source diffusion and investigates an experimental laboratory smoke environment using an ammonium chloride smoke agent.The particle size distribution,composition,and mass flow distribution of the smoke were studied.Based on a discrete phase model and a kεturbulence model,a numerical simulation was developed to model the smoke generation and diffusion processes of the smoke agent in a confined space.The temporal and spatial distribution characteristics of the smoke mass concentration,velocity,and temperature in the space after smoke generation were analyzed,and the motion law governing the smoke diffusion throughout the entire space was summarized.Combined with the experimental verification of the smoke environment laboratory,the results showed that the smoke plume changed from fan-shaped to umbrella-shaped during smoke generation,and then continued to spread around.Meanwhile,the mass concentration of smoke in the space decreased from the middle outward;the changes in temperature and velocity were small and stable.In the diffusion stage(after 900 s),the mass concentration of smoke above 0.8 m was relatively uniform across an area of smoke that was 12 m thick.The concentration decreased over time,following a consistent decreasing trend,and the attenuation was negligible in a very short time.Therefore,this system was suitable for conducting experimental research on laser fuzes in a smoke environment.Owing to the stability of the equipment and facilities,the setup could reproduce the same experimental smoke environment by artificially controlling the smoke emission of the smoke agent.Overall,this work provides a theoretical reference for subsequent research efforts regarding the construction of uniform smoke environments and evaluating laser transmission characteristics in smoky environments.

Dose-response relationship of lung cancer to amount smoked, duration and age starting

AIM: To quantify smoking/lung cancer relationships accurately using parametric modelling. METHODS: Using the International Epidemiological Studies on Smoking and Lung Cancer database of all epidemiological studies of 100+ lung cancer cases published before 2000, we analyzed 97 blocks of data for amount smoked, 35 for duration of smoking, and 27 for age started. Pseudo-numbers of cases and controls(or at risk) estimated from RRs by dose level formed the data modelled. We fitted various models relating loge RR to dose(d), including βd, βdY and βloge(1 + Wd),and investigated goodness-of-fit and heterogeneity between studies. RESULTS: The best-fitting models for loge RR were0.833 loge [1 +(8.1c/10)] for cigarettes/d(c), 0.792(y/10)0.74 for years smoked(y) and 0.176 [(70- a)/10]1.44 for age of start(a). Each model fitted well overall, though some blocks misfitted. RRs rose from 3.86 to 22.31 between c = 10 and 50, from 2.21 to 13.54 between y = 10 and 50, and from 3.66 to 8.94 between a = 30 and 12.5. Heterogeneity(P < 0.001) existed by continent for amount, RRs for 50 cigarettes/d being 7.23(Asia), 26.36(North America) and 22.16(Europe). Little heterogeneity was seen for duration of smoking or age started. CONCLUSION: The models describe the dose-relationships well, though may be biased by factors including misclassification of smoking status and dose.

Detection of nicotine from secondhand smoke as a marker compound

About millions of people die yearly due to tobacco use.A number that has been estimated byWorld Health Organization will be double in next 15 years.Over the past decade significant progress has been made around theworld in controlling involuntary exposure of nonsmokers to the Secondhand smoke(SHS).In some country expanding workplace restriction now protect a majority of working adults,but the home remains the most important exposure setting for children.The BIDI is often called the poor man’s cigarette and is perhaps the cheapest tobacco smoking product in the world.Most often found in India,it is more harmful than cigarette and is one of the major sources for Secondhand smoke.

Salivary immunoglobulin classes in Nigerian smokers with periodontitis

AIM:To determine the levels of salivary immunoglobulin classes in Nigerian smokers and non-smokers with periodontitis.METHODS:Sixty-nine individuals were recruited into this study after obtaining informed consent.They were subdivided into three groups that consisted of 20(aged 46 ± 11 years) cigarette smokers with periodontitis(S+P);24(40 ± 12 years) smokers without periodontitis(S-P);and 25(53 ± 11 years) non-smokers with periodontitis(NS+P).An oral and maxillofacial surgeon used radiographs for periodontal probing for the diagnosis of periodontitis.The smokers included subjects who smoked at least six cigarettes per day and all the periodontitis patients were newly diagnosed.About 5 mL of unstimulated saliva was expectorated by each subject into plain sample bottles.Salivary immunoglobulin levels were estimated using enzyme linked immunosorbent assay.Student's t test was used to deter-mine significant differences between the means.Values of P < 0.05 were regarded as significant.RESULTS:No significant differences were observed in the mean salivary levels of the immunoglobulin classes(IgG,IgA,IgM and IgE) when S+P was compared with S-P.Mean salivary levels of IgA(520.0 ± 155.1 ng/mL vs 670.0 ± 110 ng/mL,P = 0.000) and IgM(644.5 ± 160.0 ng/mL vs 791.4 ± 43.7 ng/mL,P = 0.000) were significantly lower in the S+P compared with NS+P group.Salivary IgA(570.4 ± 145.6 ng/mL vs 670.0 ± 110 ng/mL,P = 0.008) and IgM(703.1 ± 169.3 ng/mL vs 791.4 ± 43.7 ng/mL,P = 0.012) levels were significantly lower in the S-P compared with NS+P group.Only one(5%) periodontal patient had detectable levels of salivary IgE(0.20 IU/mL).Similarly,only one smoker(4.17%) had detectable levels of salivary IgE(0.04 IU/mL) and two non-smokers(9.52%) had detectable levels of IgE(0.24 IU/mL).CONCLUSION:Our study suggests that reduced salivary IgA and IgM levels in smokers with periodontitis could enhance increased susceptibility to periodontitis.

Autodesk Smoke2012工作站测试报告

本文对Smoke工作站3D节目后期制作流程进行了测试,介绍了测试系统硬件配置及软件版本组成,以及如何利用工作站进行视频信号的采集与输出、文件的导入与导出,特别是对P2与XDCAM文件进行导入的流程,同时介绍了利用Smoke2012对3D素材进行剪辑与合成的功能。

Population-Based Survey of Secondhand Smoke Exposure in China

Objective To determine the extent of secondhand smoke exposure in China, and to explore the potential associated factors. Methods This study was a nationally representative household survey examining secondhand smoke exposure of non-institutionalized men and women aged 15 and older using a global standardized geographically clustered sample design. A total of 13 354 people completed the individual questionnaire with questions on gender, age, educational level, residence, profession, potential factors associated with secondhand smoke exposure, and workplace smoking policy. The data were used to determine whole population estimates of secondhand smoke exposure. Results Among non-smokers aged 15 years and older, it was estimated that 72.4% （556 million） were exposed to secondhand smoke, with 52.5% （292 million） exposed to secondhand smoke daily. The prevalence of secondhand smoke exposure was 74.1% for men, 71.6% for women, 70.5% for urban populations, and 74.2% for rural populations. The rates were 67.3%, 63.3%, and 72.7% respectively, within the household, indoor workplaces and public places. Secondhand smoke exposure was significantly reduced in workplaces with a smoking ban but not in workplaces with a partial smoking ban. Conclusion Although China has made some progress toward a smoke-free environment there remains a high degree of exposure to secondhand smoke.

基于Smoke仿真分析在器件降额设计中的应用

器件降额设计是电路可靠性设计中的一种常用方法,通过降额设计可以达到降低器件基本失效率、提高产品使用可靠性的目的。传统的降额设计存在计算量大、耗时长、是一种静态分析方法、无法估计器件瞬态应力的缺点,基于Smoke仿真分析的降额设计可以准确分析电路中各个器件的瞬态电应力和器件结温,并直接输出所有器件的应力分析和降额情况,从而大大提高了降额设计的准确性和效率。本文采用OrCAD公司PSpice软件中的Smoke高级分析模块,对飞机刹车控制电路的V/I转换模块进行了降额设计仿真,验证了该方案的可行性,从而为电路的降额设计提供了一种新的手段,说明在Smoke分析基础上进行降额设计的研究具有重要的实用意义。

Berberine Attenuates Cigarette Smoke Extract-induced Airway Inflammation in Mice:Involvement of TGF-β1/Smads Signaling Pathway

Although several studies confirmed that berberine may attenuate airway inflammation in mice with chronic obstructive pulmonary disease(COPD),its underlying mechanisms were not clear until now.We aimed to establish an experiment mouse model for COPD and to investigate the effects of berberine on airway inflammation and its possible mechanism in COPD model mice induced by cigarette smoke extract(CSE).Twenty SPF C57BL/6 mice were randomly divided into PBS control group,COPD model group,low-dose berberine group and high-dose berberine group,5 mice in each group.The neutrophils and macrophages were examined by Wright's staining.The levels of inflammatory cytokines TNF-α and IL-6 in bronchoalveolar lavage fluid(BALF)were detennined by enzyme-linked immunosorbent assay.The expression levels of TGF-β1,Smad2 and Smad3 mRNA and proteins in lung tissues were respectively detected by quantitative real-time polymerase chain reaction and Western blotting.It was found that CSE increased the number of inflammation cells in BALF,elevated lung inflammation scores,and enhanced the TGF-β1/Smads signaling activity in mice.High-dose berberine restrained the alterations in the COPD mice induced by CSE.It was concluded that high-dose berberine ameliorated CSE-induced airway inflammation in COPD mice.TGF-β1/Smads signaling pathway might be involved in the mechanism.These findings suggested a therapeutic potential of high-dose berberine on the CSE-induced airway inflammation.