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LSDA-APF:A Local Obstacle Avoidance Algorithm for Unmanned Surface Vehicles Based on 5G Communication Environment

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工程与科学中的计算机建模(英文) 2024年第1期138卷 595-617页

作者： xiaoli Li Tongtong Jiao Jinfeng Ma Dongxing duan Shengbin Liang School of Software Henan UniversityKaifeng475004China

In view of the complex marine environment of navigation,especially in the case of multiple static and dynamic obstacles,the traditional obstacle avoidance algorithms applied to unmanned surface vehicles(USV)are prone to fall into the trap of local optimization.Therefore,this paper proposes an improved artificial potential field(APF)algorithm,which uses 5G communication technology to communicate between the USV and the control center.The algorithm introduces the USV discrimination mechanism to avoid the USV falling into local optimization when the USV encounter different obstacles in different scenarios.Considering the various scenarios between the USV and other dynamic obstacles such as vessels in the process of performing tasks,the algorithm introduces the concept of dynamic artificial potential field.For the multiple obstacles encountered in the process of USV sailing,based on the International Regulations for Preventing Collisions at Sea(COLREGS),the USV determines whether the next step will fall into local optimization through the discriminationmechanism.The local potential field of the USV will dynamically adjust,and the reverse virtual gravitational potential field will be added to prevent it from falling into the local optimization and avoid collisions.The objective function and cost function are designed at the same time,so that the USV can smoothly switch between the global path and the local obstacle avoidance.The simulation results show that the improved APF algorithm proposed in this paper can successfully avoid various obstacles in the complex marine environment,and take navigation time and economic cost into account.

关键词： Unmanned surface vehicles local obstacle avoidance algorithm artificial potential field algorithm path planning collision detection

Several major issues concerning the environmental transmission and risk prevention of SARS-CoV-2

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Science China Earth Sciences 2022年第6期65卷 1047-1056页

作者： Jin MA Jian XU xiaoli ZHAO Shouliang HUO xiaoli duan Yunsong MU Ying WANG Yuan WEI Jiang CHANG Xiaowei JIN Fengchang WU State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental SciencesBeijing 100012China School of Energy and Environmental Engineering University of Science and Technology BeijingBeijing 100083China School of Environment and Nature Resource Renmin University of ChinaBeijing 100872China School of Space and Environment Beihang UniversityBeijing 102206China China National Environmental Monitoring Centre Beijing 100012China

Coronavirus disease 2019(COVID-19) is the most serious infectious disease pandemic in the world in a century, and has had a serious impact on the health, safety, and social and economic development of all mankind. Since the earth entered the“Anthropocene”, human activities have become the most important driving force of the evolution of the earth system. At the same time, the epidemic frequency of major human infectious diseases worldwide has been increasing, with more than 70% of novel diseases having zoonotic origins. The review of several major epidemics in human history shows that there is a common rule, i.e., changes in the natural environment have an important and profound impact on the occurrence and development of epidemics. Therefore, the impact of the natural environment on the current COVID-19 pandemic and its mechanisms have become scientific issues that need to be resolved urgently. From the perspective of the natural environment, this study systematically investigated several major issues concerning the environmental transmission and risk prevention of Severe Acute Respiratory Syndrome Coronavirus 2(SARS-CoV-2). From a macroscopic temporal and spatial scale, the research focus on understand the impact of the destruction of the natural environment and global changes on the outbreak of infectious diseases;the threat of zoonotic diseases to human health;the regularity for virus diffusion, migration and mutation in environmental media;the mechanisms of virus transmission from animals and environmental media to humans;and environmental safety, secondary risk prevention and control of major epidemics. Suggestions were made for future key research directions and issues that need attention, with a view to providing a reference for the prevention and control of the global coronavirus disease 2019, and to improving the ability of response to major public health emergencies.

关键词： SARS-CoV-2 Environmental transmission Risk prevention Zoonotic diseases Ecological security

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A Social Intervention Approach to Rehabilitate the Health Psychology of Leftbehind Children with Psychological Problems in Healthcare Settings

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International Journal of Mental Health Promotion 2022年第3期24卷 415-423页

作者： Qijie Jiang Chi Zhang xiaoli duan Siyi Pei Business School Chengdu UniversityChengdu610106China School of Management The University of SheffieldWestern BankSheffieldS102TNUK School of Economic and Management Zhengzhou Normal UniversityZhengzhou450044China Sichuan Academy of Social Science Chengdu610071China

Background:Left-behind children are more inclined to generate psychological problems relative to non-leftbehind children,thus how to rehabilitate their health psychology and promote the psychological health development of this special disadvantaged group in healthcare settings should be paid more attention to.Objective:This paper attempts to present a social intervention approach and explore its impact on the rehabilitation of rural leftbehind children’s psychological problems in healthcare settings.Methods:This study firstly designed a social intervention program based on the health psychology theory and the generation causes of left-behind children’s psychological problems,and then three groups were applied to test the effectiveness of the program with comparison analysis.Results:Compared with the control left-behind children(group 2),the left-behind children in the experimental group 1 had positive changes in learning anxiety,physical symptoms,anxiety about people,loneliness tendency,self-blame tendency,allergy tendency,terror tendency and impulse tendency.And their mental health can be rehabilitated to the level of non-left-behind children in group 3.Conclusion:This study revealed positive effects of specially designed social intervention program on the rehabilitation of left-behind children’s psychological problems in healthcare settings.The results have both theoretical and practical implications.

关键词： Health psychology left-behind children rehabilitation healthcare settings experiment

Collaborative control of fine particles and ozone required in China for health benefit

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环境科学与工程前沿(英文) 2023年第8期17卷 1-11页

作者： Ling Qi Zhige Tian Nan Jiang Fangyuan Zheng Yuchen Zhao Yishuo Geng xiaoli duan School of Energy and Environmental Engineering University of Science and Technology BeijingBeijing 100083China

PM2.5 concentration declined significantly nationwide,while O3 concentration increased in most regions in China in 2013–2020.Recent evidences proved that peak season O3 is related to increased death risk from non-accidental and respiratory diseases.Based on these new evidences,we estimate excess deaths associated with long-term exposure to ambient PM2.5 and O3 in China following the counterfactual analytic framework from Global Burden Disease.Excess deaths from non-accidental diseases associated with long-term exposure to ambient O3 in China reaches to 579(95%confidential interval(CI):93,990)thousand in 2020,which has been significantly underestimated in previous studies.In addition,the increased excess deaths associated with long-term O3 exposure(234(95%CI:177,282)thousand)in 2013–2020 offset three quarters of the avoided excess deaths(302(95%CI:244,366)thousand)mainly due to PM2.5 exposure reduction.In key regions(the North China Plain,the Yangtze River Delta and the Fen-Wei Plain),the former is even larger than the latter,particularly in 2017–2020.Health benefit of PM2.5 concentration reduction offsets the adverse effects of population growth and aging on excess deaths attributed to PM2.5 exposure.Increase of excess deaths associated with O3 exposure is mainly due to the strong increase of O3 concentration,followed by population aging.Considering the faster population aging process in the future,collaborative control,and faster reduction of PM2.5 and O3 are needed to reduce the associated excess deaths.

关键词： Excess deaths Long-term exposure Fine particle Ozone

Role of Meteorological Parameters in COVID-19 Pandemic Waves in Delhi, India

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Open Journal of Air Pollution 2023年第2期12卷 31-49页

作者： Deepak Gupta xiaoli duan School of Energy and Environmental Engineering University of Science and Technology Beijing Beijing China

In this study, the levels of meteorological parameters like maximum temperature (°F), relative temperature (°F), minimum temperature (°F), humidity (%), dew point (°F), wind speed (mph), rainfall (in), and air pressure (in) were analyzed for all three COVID-19 pandemic waves in the NCT of Delhi, India. After doing statistical analysis, the results showed that only a few parameters, like temperature (maximum, minimum, and relative), dew point, humidity, and air pressure, were linked to the start of COVID-19 pandemic waves, and rainfall had nothing to do with COVID-19 during any of the three waves. So, according to the results of this study, the Indian government should take strict steps to stop the spread of the fourth wave of COVID-19 and any other diseases that can spread in urban areas based on the meteorological conditions.

关键词： COVID-19 Meteorological Parameters SARS-CoV-2 Correlation

Health risk assessment of dietary exposure to polycyclic aromatic hydrocarbons in Taiyuan, China

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Journal of Environmental Sciences 2014年第2期26卷 432-439页

作者： Jing Nie Jing Shi xiaoli duan Beibei Wang Nan Huang Xiuge Zhao Chinese Research Academy of Environmental Sciences State Key Lab of Environmental Criteria and Risk Assessment Soil and Water Science College of Resources and Environmental Sciences China Agricultural University Department of Safety Engineering China Institute of Industrial Relations

Sixteen polycyclic aromatic hydrocarbons （PAHs） were determined in 24 duplicate-diet samples from people in Taiyuan during summer and winter in 2009. Dietary intake of PAHs for 2862 participants was subsequently estimated by a survey in Taiyuan. Results from these 24 samples were compared with a raw food study in Taiyuan in 2008. Three main sources of dietary PAHs are vegetables, wheat flour and fruits, the sum of which contributes 75.95% of PAHs in dietary food. Compared to the estimated value in raw food, much more B[a]Peq （benzo[a]pyrene equivalents） were detected in food samples collected in the duplicate-diet study in Taiyuan （60.75 ng/day）. The cooking process may introduce more B[a]Peq into food, and the relative contribution of 16 PAHs in the diet would be changed during the cooking procedure.

关键词： dietary exposure food health risk assessment polycyclic aromatic hydrocarbons （PAHs） benzo[a]pyrene

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Effect of temperature on Lu’an bituminous char structure evolution in pyrolysis and combustion

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Frontiers in Energy 2021年第1期15卷 14-25页

作者： Yandi ZHANG Yinhe LIU xiaoli duan Yao ZHOU Xiaoqian LIU Shijin XU State Key Laboratory of Multiphase Flow in Power Engineering Xi'an Jiaotong UniversityXi'an 710049China

In the process of pyrolysis and combustion of coal particles, coal structure evolution will be affected by the ash behavior, which will further affect the char reactivity, especially in the ash melting temperature zone. Lu’an bituminous char and ash samples were prepared at the N_(2) and air atmospheres respectively across ash melting temperature. A scanning electron microscope (SEM) was used to observe the morphology of char and ash. The specific surface area (SSA) analyzer and thermogravimetric analyzer were respectively adopted to obtain the pore structure characteristics of the coal chars and combustion parameters. Besides, an X-ray diffractometer (XRD) was applied to investigate the graphitization degree of coal chars prepared at different pyrolysis temperatures. The SEM results indicated that the number density and physical dimension of ash spheres exuded from the char particles both gradually increased with the increasing temperature, thus the coalescence of ash spheres could be observed obviously above 1100℃. Some flocculent materials appeared on the surface of the char particles at 1300℃, and it could be speculated that β-Si_(3)N_(4) was generated in the pyrolysis process under N_(2). The SSA of the chars decreased with the increasing pyrolysis temperature. Inside the char particles, the micropore area and its proportion in the SSA also declined as the pyrolysis temperature increased. Furthermore, the constantly increasing pyrolysis temperature also caused the reactivity of char decrease, which is consistent with the results obtained by XRD. The higher combustion temperature resulted in the lower porosity and more fragments of the ash.

关键词： bituminous char pyrolysis ash structure evolution reactivity

舒适护理在慢性阻塞性肺疾病伴Ⅱ型呼吸衰竭患者无创呼吸机治疗中的应用效果

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中国社区医师 2024年第1期40卷 105-107页

作者：段晓莉兴化市人民医院江苏兴化225700

目的:探讨舒适护理在慢性阻塞性肺疾病(COPD)伴Ⅱ型呼吸衰竭患者无创呼吸机治疗中的应用效果。方法:选取2021年1月—2022年10月于兴化市人民医院呼吸科行无创呼吸机治疗的COPD伴Ⅱ型呼吸衰竭患者64例作为研究对象,采用随机数字表法分为... 详细信息

目的:探讨舒适护理在慢性阻塞性肺疾病(COPD)伴Ⅱ型呼吸衰竭患者无创呼吸机治疗中的应用效果。方法:选取2021年1月—2022年10月于兴化市人民医院呼吸科行无创呼吸机治疗的COPD伴Ⅱ型呼吸衰竭患者64例作为研究对象,采用随机数字表法分为两组,各32例。对照组实施常规护理,研究组实施舒适护理。比较两组护理效果。结果:护理后,研究组遵医治疗、配合检查、配合护理、生理舒适、心理舒适以及环境舒适评分均高于对照组,并发症总发生率低于对照组,差异有统计学意义(P<0.05)。结论:舒适护理在COPD伴Ⅱ型呼吸衰竭患者无创呼吸机治疗中的应用效果理想,可提升患者依从性、舒适度,减少并发症。

关键词：舒适护理慢性阻塞性肺疾病 Ⅱ型呼吸衰竭无创呼吸机

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Increased urbanization reduced the effectiveness of school closures on seasonal influenza epidemics in China

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贫困所致传染病(英文) 2021年第5期10卷 52-61页

作者： Hao Lei Hangjin Jiang Nan Zhang xiaoli duan Tao Chen Lei Yang Dayan Wang Yuelong Shu Shenzhen Campus of Sun Yat-Sen University University of Science and Technology Beijing Collaboration Innovation Center for Diagnosis and Treatment of Infectious Diseases Zhejiang University People’s Republic of ChinaKey Laboratory of Green Built Environment and Energy Efficient Technology Guangdong 518107 People’s Republic of ChinaSchool of Energy and Environmental Engineering Beijing 102206 Key Laboratory for Medical Virology No. 66 ChinaNational Institute for Viral Disease Control and Prevention School of Public Health Guangming District National Health Commission Beijing University of Technology Chinese Center for Disease Control and Prevention Hangzhou People’s Republic of ChinaNational Institute for Viral Disease Control and Prevention Gongchang Road People’s Republic of ChinaCenter for Data Science People’s Republic of ChinaSchool of Public Health (Shenzhen)

Background: School closure is a common mitigation strategy during severe influenza epidemics and pandemics. However, the effectiveness of this strategy remains controversial. In this study, we aimed to explore the effectiveness of school closure on seasonal influenza epidemics in provincial-level administrative divisions (PLADs) with varying urbanization rates in China.Methods: This study analyzed influenza surveillance data between 2010 and 2019 provided by the Chinese National Influenza Center. Taking into consideration the climate, this study included a region with 3 adjacent PLADs in Northern China and another region with 4 adjacent PLADs in Southern China. The effect of school closure on influenza transmission was evaluated by the reduction of the effective reproductive number of seasonal influenza during school winter breaks compared with that before school winter breaks. An age-structured Susceptible-Infected-Recovered-Susceptible (SIRS) model was built to model influenza transmission in different levels of urbanization. Parameters were determined using the surveillance data via robust Bayesian method.Results: Between 2010 and 2019, in the less urbanized provinces: Hebei, Zhejiang, Jiangsu and Anhui, during school winter breaks, the effective reproductive number of seasonal influenza epidemics reduced 14.6% [95% confidential interval (CI): 6.2-22.9%], 9.6% (95%CI: 2.5-16.6%), 7.3% (95%CI: 0.1-14.4%) and 8.2% (95%CI: 1.1-15.3%) respectively. However, in the highly urbanized cities: Beijing, Tianjin and Shanghai, it reduced only 5.2% (95%CI: -0.7-11.2%), 4.1% (95%CI: -0.9-9.1%) and 3.9% (95%CI: -1.6-9.4%) respectively. In China, urbanization is associated with decreased proportion of children and increased social contact. According to the SIRS model, both factors could reduce the impact of school closure on seasonal influenza epidemics, and the proportion of children in the population is thought to be the dominant influencing factor.Conclusions: Effectiveness of school closure on the epidemics varies with th

关键词： School closure Influenza epidemics Urbanization Contact China