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华北抗日根据地的医疗卫生工作——以医疗卫生展览为例

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河北开放大学学报 2024年第4期29卷 1-6页

作者：王志峰焦冰睿山西大学马克思主义学院山西太原030006

抗日战争时期,由于华北革命根据地迷信思想存在、卫生防疫意识缺乏,再加上战争频发和敌伪投毒,疾疫严重威胁着根据地人民的生命健康,导致人民生活水平和生产力下降,影响到军队士兵战斗效能的发挥。为此华北抗日根据地举办了一系列包括... 详细信息

抗日战争时期,由于华北革命根据地迷信思想存在、卫生防疫意识缺乏,再加上战争频发和敌伪投毒,疾疫严重威胁着根据地人民的生命健康,导致人民生活水平和生产力下降,影响到军队士兵战斗效能的发挥。为此华北抗日根据地举办了一系列包括建立医疗机构和培养医务人员、强调公共卫生与家庭卫生、反对封建迷信与提倡科学就医、自主研发医疗器械与药品等为主要内容的医疗卫生展览。这些展览由专业人士和卫生部门参与筹办,注重展品的选取陈列和观众的互动反馈,增强了根据地人民的卫生观念和政治认同,促进了根据地中西医的进一步合作和卫生防疫事业的进步。

关键词：抗日战争华北抗日根据地医疗卫生工作展览

我国本科临床医学类专业招生规模的时空布局分析

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医学与哲学 2024年第7期45卷 76-80页

作者：贾雅雯侯建林王志锋北京大学公共卫生学院北京100191 北京大学医学教育研究所/全国医学教育发展中心北京100191 北京大学医学部卫生政策与技术评估中心北京100191

1998—2019年,我国普通高校本科临床医学类专业招生规模显著增长,院校由90所增至181所;招生人数由2.9万人增至9.6万人。不同地区的招生规模差异较大,具有显著的空间正相关性,即招生规模相似的省份在空间上趋于聚集。高-高聚类主要位于... 详细信息

1998—2019年,我国普通高校本科临床医学类专业招生规模显著增长,院校由90所增至181所;招生人数由2.9万人增至9.6万人。不同地区的招生规模差异较大,具有显著的空间正相关性,即招生规模相似的省份在空间上趋于聚集。高-高聚类主要位于经济发达、高等教育发展历史悠久、地理位置优越的地区,如华东地区;而低-低聚类则多位于经济社会发展水平较低、基础设施建设滞后的地区,如西北地区。因此,应进一步优化招生规模在地区间的分布,通过制定实施倾斜性的政策、进行资源支持、发挥地区带动效应等促进招生规模的区域均衡布局。

关键词：本科临床医学类专业普通高校招生规模地区分布

下一代太阳能热发电中固体颗粒吸热器研究进展

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中国电机工程学报 2024年第18期44卷 7293-7308,I0016页

作者：张亚南唐宪友聂辅亮姚磐白凤武王志峰中国广核新能源控股有限公司北京市丰台区100160 中国科学院电工研究所北京市海淀区100190 中国科学院大学北京市海淀区100190

以化学惰性的固体颗粒作为下一代太阳能热发电系统中的传热流体和储热介质,可以使集热和储热系统的运行温度超过800℃,有望大幅度提高太阳能热发电系统的年均发电效率,进而降低发电成本。固体颗粒吸热器是太阳能热发电系统中的核心设备... 详细信息

以化学惰性的固体颗粒作为下一代太阳能热发电系统中的传热流体和储热介质,可以使集热和储热系统的运行温度超过800℃,有望大幅度提高太阳能热发电系统的年均发电效率,进而降低发电成本。固体颗粒吸热器是太阳能热发电系统中的核心设备,国内外研究团队提出了多种技术方案。该文根据颗粒流动方式的不同对各种固体颗粒吸热器技术进行分类,并对各种固体颗粒吸热器技术的研究进展进行介绍,重点阐述了优化吸热器结构和颗粒流动特性对吸热器热性能的提升作用。此外,通过各种固体吸热器热性能参数的对比分析,结合其运行特征总结出面临的技术挑战,并提出相应的优化策略,可为固体颗粒吸热器的优化设计提供指导。

关键词：下一代太阳能热发电固体颗粒吸热器颗粒流动热性能参数

Assessment of Storm Surge and Flood Inundation in Chittagong City of Bangladesh Based on ADCIRC and GIS

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Journal of Ocean University of China 2023年第6期22卷 1473-1486页

作者： LIU Yuxin LI Songtao wang zhifeng National Ocean Technology Center Tianjin 300110China Shandong Provincial Key Laboratory of Ocean Engineering&College of Engineering Ocean University of ChinaQingdao 266100China

Coastal flooding caused by tropical cyclones has long been a major threat to life,property,and infrastructure in coastal *** study assessed the risk of flooding in Chittagong,southeastern Bangladesh,under extreme sea level scenarios caused by high astronomical tides and storm *** Jelesnianski typhoon model and the ADvanced CIRCulation hydrodynamic model were used to simulate 91 typhoons that occurred in the Bay of Bengal between 1981 and 2017,and observational data were used for model *** inundation model was based on a digital elevation model and a seed spread algorithm,and a geographical information system was used to visualize the flood *** four scenarios,the changes in flood levels caused by sea level rise had no signifi-cant influence on the extent of flooding in *** flood levels of 8.82m(50-year storm surge without sea level rise)and 8.89 m(50-year storm surge with sea level rise),the maximum estimated area of inundation was 11.35 km^(2).The western coastal and southeastern river coastal plain areas of Chittagong have the highest risk of inundation due to their low-lying *** flood levels of 9.83m(100-year storm surge without sea level rise)and 9.97m(100-year storm surge with sea level rise),the maximum simulated flood extent was 36.44km^(2).Simulated floodwaters propagated in a south–north direction,and most of the northern areas of the city are at risk of inundation under these scenarios.

关键词： typhoon storm surge extreme sea level inundation

Intensity of Level Ice Simulated with the CICE Model for Oil-Gas Exploitation in the Southern Kara Sea, Arctic

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Journal of Ocean University of China 2022年第5期21卷 1099-1108页

作者： DUAN Chenglin wang zhifeng DONG Sheng College of Engineering Ocean University of ChinaQingdao 266100China

Sea ice is the predominant natural threat to marine structures and oil-gas exploitation in the ***,for ice-resistant structural design,long-term successive level ice thickness measurements are still *** fill this gap in the southern Kara Sea,the Los Alamos Sea Ice Model(CICE)is applied to achieve better simulation at the local and regional *** on the validation against ice thickness observations in March and April in 1980-1986,the statistical root-mean-square error is determined to be less than 0.2 ***,based on the hindcast data,the spatiotemporal distributions of level ice thickness are analyzed annually,seasonally,and monthly,with thicker level ice of 1.2-1.5 m in spring and large ice-free zones in September and *** floating platforms,a novel ice grade criterion with five classifications,namely,excellent,good,moderate,severe,and catastrophic,is *** first two grades are most suitable for offshore activities,particularly from August to October,and the moderate grade is acceptable if with ice-resistant ***,hostile ice conditions are discussed in terms of the generalized extreme value *** statistics reveal that at a return period of 100 yr,extreme level ice is primarily between 0.6 m and 1.0 m in *** present investigation could be a useful reference for a feasibility study of the potential risk analysis and ice-resistant operation of oil-gas exploitation in the Arctic.

关键词： level ice CICE spatiotemporal distribution return period ice-resistant floating platform southern Kara Sea

基于GSL-YOLO模型的综放工作面混矸率检测方法

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工矿自动化 2024年第9期50卷 59-65,137页

作者：王福奇王志峰金建成井庆贺王耀辉王大龙汪义龙华能庆阳煤电有限责任公司甘肃庆阳745000 中国矿业大学(北京)能源与矿业学院北京100083 华亭煤业集团有限责任公司甘肃平凉744100 扎赉诺尔煤业有限责任公司内蒙古满洲里021410 华能煤炭技术研究有限公司北京100071 华能云南滇东能源有限责任公司云南曲靖655500 华能煤业有限公司陕西矿业分公司陕西西安710001

针对现有基于深度学习的综放工作面混矸率检测方法在井下低照度、高粉尘、煤矸堆叠等复杂条件下存在煤矸识别精度低、分割效果差、模型参数量和运算量大、未实现混矸率的实时检测等问题,提出了一种基于GSL-YOLO模型的混矸率检测方法。GS... 详细信息

针对现有基于深度学习的综放工作面混矸率检测方法在井下低照度、高粉尘、煤矸堆叠等复杂条件下存在煤矸识别精度低、分割效果差、模型参数量和运算量大、未实现混矸率的实时检测等问题,提出了一种基于GSL-YOLO模型的混矸率检测方法。GSL-YOLO模型在YOLOv8-seg的基础上进行以下改进:在主干网络中引入全局注意力机制(GAM),通过减少信息弥散和放大全局交互表示提高模型特征提取能力;选用具有高效局部聚合网络的空间金字塔池化(SPPELAN)模块,提升模型处理不同尺寸目标时的检测性能;采用轻量级非对称多级压缩检测头(LADH),降低模型的训练难度,同时提高推理速度。提出了一种基于类别分割掩码的混矸率计算方法,该方法基于煤流图像处理结果中的分割掩码信息,计算其中矸石的像素面积与总像素面积的比值,作为瞬时混矸率。实验结果表明:(1)GSL-YOLO模型的m AP@0.5∶0.95达96.1%,比YOLOv8-seg模型提高了0.8%。(2)GSL-YOLO模型的参数量为2.9×10^(6)个,浮点运算次数为11.4×10^(9),模型权重为6.0MiB,比YOLOv8-seg模型分别降低了12.1%,5.8%,11.8%,实现了模型的轻量化。(3)GSL-YOLO模型在测试集上的帧率为12帧/s,基本满足实时检测要求。(4)与YOLO系列模型相比,GSL-YOLO模型分割效果最好,检测精度最高,参数量和运算量较少,综合性能最佳。(5)基于截取的综放工作面后部刮板输送机上煤流视频中的3帧图像,计算了瞬时混矸率,结果表明,提出的混矸率计算方法基本实现了综放工作面混矸率的实时计算。

关键词：智能放煤煤矸识别混矸率检测 YOLOv8-seg 图像分割全局注意力机制非对称检测头

Dynamic Simulation of a Novel Solar Polygeneration System for Heat, Power and Fresh Water Production based on Solar Thermal Power Tower Plant

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Journal of Thermal Science 2020年第2期29卷 378-392页

作者： LI Xing wang zhifeng YANG Ming YUAN Guofeng Key Laboratory of Solar Thermal Energy and Photovoltaic System Chinese Academy of SciencesBeijing 100190China Institute of Electrical Engineering Chinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China Beijing Engineering Research Center of Solar Thermal Power Beijing 100190China

A novel solar polygeneration system for heat, power and fresh water production with absorption heat pump(AHP) and humidification-dehumidification(HDH) desalination system was proposed for high-efficiency utilization of solar energy. A case study of the proposed system was investigated based on 1 MW solar thermal power(STP) tower plant located in Beijing. Depending on mathematical modeling of the proposed system, corresponding modules were developed in TRNSYS. Meanwhile, control and operation strategies were fully studied with principal of solar energy cascade utilization. The thermodynamic performance of the proposed system was dynamically simulated at one minute intervals in a typical day. It was found that solar energy utilization level was improved with the help of solar thermal storage system and continuous heating in different operation modes met well with flexible heating loads from 93.76 kW to 169.49 kW. During AHP operation period, its Coefficient of Performance(COP) varied from 1.39 to 1.73 due to recoverable condensate heat restricted by heating demand. Meanwhile, fresh water production of HDH increased from 352.05 kg/h to 416.62 kg/h with Gained Output Ratio(GOR) increase from 2.48 to 2.67. Compared with original STP tower plant, maximum power generation efficiency was increased from 18.66% to 19.22% with power from 1169.69 kW to 1204.44 kW.

关键词： polygeneration solar thermal power dynamic simulation absorption heat pump humidification-dehumidification

Thermal performance of a single-layer packed metal pebble-bed exposed to high energy fluxes

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Frontiers in Energy 2021年第2期15卷 513-528页

作者： Shengchun ZHANG zhifeng wang Hui BIAN Pingrui HUANG Key Laboratory of Solar Thermal Energy and Photovoltaic System Chinese Academy of SciencesBeijing 100190China Institute of Electrical Engineering Chinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100190China Beijing Engineering Research Center of Solar Thermal Power Beijing 100190China 2.Lanzhou University of TechnologyLanzhou 730050China

It is difficult to accurately measure the temperature of the falling particle receiver since thermocouples may directly be exposed to the solar *** study analyzes the thermal performance of a packed bed receiver using large metal spheres to minimize the measurement error of particle temperature with the sphere temperature reaching more than 700°C in experiments in a solar furnace and a solar *** numerical models of a single sphere and multiple spheres are verified by the *** multiple spheres model includes calculations of the external incidence,view factors,and heat *** effects of parameters on the temperature variations of the spheres,the transient thermal efficiency,and the temperature uniformity are investigated,such as the ambient temperature,particle thermal conductivity,energy flux,sphere diameter,and sphere *** the convection is not considered,the results show that the sphere emissivity has a significant influence on the transient thermal efficiency and that the temperature uniformity is strongly affected by the energy flux,sphere diameter,and sphere *** the emissivity increases from 0.5 to 0.9,the transient thermal efficiency and the average temperature variance increase from 53.5%to 75.7%and from 14.3%to 27.1%at 3.9 min,*** average temperature variance decreases from 29.7%to 9.3%at 2.2 min with the sphere diameter increasing from 28.57 mm to 50 *** the dimensionless energy flux increases from 0.8 to 1.2,the average temperature variance increases from 13.4%to 26.6%at 3.4 min.

关键词： packed bed solar thermal power plants high heat fluxes radiative heat transfer

Experimental Study on Melting Process in an Industrial Level Molten Salt Tank

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Journal of Thermal Science 2020年第2期29卷 457-463页

作者： LI Zhi ZHANG Qiangqiang wang zhifeng LI Jun Key Laboratory of Solar Thermal Energy and Photovoltaic System of Chinese Academy of Sciences Beijing 100190China Institute of Electrical Engineering Chinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China Beijing Engineering Research Center of Solar Thermal Power Beijing 100190China

Thermal energy storage(TES) is an important part of concentrating solar power(CSP) plants. The primary advantage of TES in CSP plants is the ability to dispatch electrical output to match peak demand periods and reduce the levelized cost of electricity. The major challenge of the molten salt is its high freezing point, leading to additional complicating freeze protection. This paper presents the experimental results of melting process of a mixed nitrate salt with a melting temperature of 115℃ in a 20 m^3 industrial level tank. Twenty electrical heaters inside the tank are used to heat the salt with a total maximum input power of 240 kW. In order to ensure a safe and fast melting process, the whole process adopted an operating strategy of combining automatic control with manual control. The whole melting process lasted for 314 hours. The salt temperature showed the greatest increase in the first 38 hours. Finally, an economic operation mode of molten salt heat storage tank was obtained.

关键词： molten salt melting concentrating solar power thermal energy storage