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1.
针对合流制管网系统在雨天溢流污染严重,造成城市水体黑臭现象的问题,以银川市某高密度城区合流制管网系统为例,基于SWMM模型,在短历时设计降雨和长历时设计降雨两种条件下,模拟分析了合流制溢流(CSO)调蓄池、雨污管道混错接改造、绿化带海绵化改造等“灰绿”协同措施对CSO污染的影响。结果表明:CSO调蓄池、雨污管道混错接改造、绿化带海绵化改造及“灰绿”措施结合4种方案在短历时、长历时设计降雨条件下,随着降水量的增加,溢流水量及溢流污染物负荷均增加,溢流削减率均逐渐减小,其中“灰绿”措施结合方案对溢流污染的削减效果最为显著;重现期小于5 a时,溢流水量削减率与溢流污染物负荷削减率基本达到80%;降雨条件为中雨时,污染物负荷削减率基本达到75%;重现期为20 a时,溢流水量削减率及TSS、COD、TP、NH^(+)_(4)-N负荷削减率分别达到64%、70%、70%、70%、70%;降雨条件为大雨时,溢流水量削减率及TSS、COD、TP、NH^(+)_(4)-N负荷削减率分别达到28%、32%、26%、31%、33%。 相似文献
2.
3.
Enhancing the earthquake behavioral responses and post-earthquake evacuation preparedness of building occupants is beneficial to increasing their chances of survival and reducing casualties after the mainshock of an earthquake. Traditionally, training approaches such as seminars, posters, videos or drills are applied to enhance preparedness. However, they are not highly engaging and have limited sensory capabilities to mimic life-threatening scenarios for the purpose of training potential participants. Immersive Virtual Reality (IVR) and Serious Games (SG) as innovative digital technologies can be used to create training tools to overcome these limitations. In this study, we propose an IVR SG-based training system to improve earthquake behavioral responses and post-earthquake evacuation preparedness. Auckland City Hospital was chosen as a case study to test our IVR SG training system. A set of training objectives based on best evacuation practice has been identified and embedded into several training scenarios of the IVR SG. Hospital staff (healthcare and administrative professionals) and visitors were recruited as participants to be exposed to these training scenarios. Participants’ preparedness has been measured along two dimensions: 1) Knowledge about best evacuation practice; 2) Self-efficacy in dealing with earthquake emergencies. Assessment results showed that there was a significant knowledge and self-efficacy increase after the training. In addition, participants acknowledged that it was easy, helpful, and engaging to learn best evacuation practice knowledge through the IVR SG training system. 相似文献
4.
“Smart firefighting” construction as a part of the “smart city” has been a concern of the public security and fire agencies at all levels. In this study, the status, problems, and reflections of “smart firefighting” construction in China are discussed. A recent survey indicates that China has launched its smart firefighting construction and initially created a new perspective on its regional smart firefighting work based on three main aspects: intelligent disaster perception by Internet of Things (IoT) construction, intelligent disaster prevention by big data construction, and intelligent disaster disposal by emergency rescue platform construction. However, the current smart firefighting construction in China still has some prominent problems such as the data interconnectivity and normalized management of various platforms, the extensibility of smart firefighting platforms, and the intelligent level of smart firefighting researches, which need to be solved urgently. Therefore, we argue that smart firefighting construction in China should establish data interconnectivity, industrial normalized management, 2D/3D geographic information interaction and extension, high-integration fire protection theory, and many other aspects in the near future and truly realize firefighting visualization and efficient data applications for 4D time space. This study could provide valuable reference for smart firefighting and smart city construction. 相似文献
5.
分析近代天津历次近代城市规划中机场布局思想的演进历程,采用比较研究方法剖析天津近代各类机场设计方案的异同及其各自特征,并总结了天津近代机场场面规制及其跑道形制在不同时期的演进规律,还从规划编制体例角度论证了天津近代机场规划及其实例应用。 相似文献
6.
青海省格尔木市西大滩东多金属矿出露地层主要为早-中三叠世昌马河地层走向呈北西~南东向,与区域构造线方向基本一致。是测区的主要矿源层,为后期矿化提供了物质基础。比较发育的北西向、北西西向逆断层具有明显的多期活动特点,多形成破碎带,为热液活动、成矿元素富集提供了良好空间,对本区矿化起着一定的控制作用,破碎蚀变带控制了土壤异常展布。本文对西大滩东多金属矿控矿因素及找矿前景进行分析探讨。 相似文献
7.
《Journal of Great Lakes research》2022,48(6):1387-1400
Sediment remediation and habitat restoration projects have been increasingly employed along the coast of the Great Lakes to improve environmental quality since the designation of 43 highly degraded Areas of Concern (AOCs) by the 1987 Great Lakes Water Quality Agreement between the U.S. and Canada. Improvements in water quality, habitat, and other environmental conditions can also support community wellbeing and revitalization; however, the mechanisms that support these connections are relatively unclear. We address this gap through a case study of three AOCs near Lake Michigan: 1) Grand Calumet River; 2) White Lake, and 3) Muskegon Lake. By analyzing secondary data and planning documents, we found that alongside environmental cleanup, anchor institutions, housing and economic development, and local events drive revitalization. Our research also illustrates that, rather than acting as discrete processes, environmental cleanup and revitalization drivers overlap in time and space. Finally, our research reveals a high level of variation within and across AOCs in terms of diverse socioeconomic contexts, planning capacities, and existing partnerships. Together, our findings point to the need for collaborative and inclusive planning processes that account for the heterogeneity present within and across AOCs to simultaneously support remediation, restoration, and revitalization and to sustain continued revitalization in AOC communities after delisting. 相似文献
8.
9.
吴良镛先生的人居环境科学理论既
为我国空间规划体系构筑了框架,也提出要有
目的有重点地运用相关学科成果进行融贯的
综合研究。最近《中共中央国务院关于建立国
土空间规划体系并监督实施的若干意见》提出
“在资源环境承载能力和国土空间开发适宜
性评价的基础上,科学有序统筹布局生态、
农业、城镇等功能空间,划定生态保护红线、
永久基本农田、城镇开发边界等空间管控边
界”,对国土空间规划体系提出进行多学科交
融研究。因此,作为国土空间规划重要基础
的国土空间开发适宜性评价需要综合考虑资
源、环境、生态、灾害等要素和区位条件,确
定国土空间内进行农业生产和城镇建设等的
适宜程度。本文主要以青岛市国土空间开发
适宜性评价为实践案例,在客观真实公正地
摸清资源环境资源本底条件基础上,研判国
土空间开发利用问题和风险,明确农业生产、
城镇建设的最大合理规模和适宜空间,落实
不同主体功能区规划背景下的战略引领,以期
支撑青岛市国土空间规划编制工作。 相似文献
10.
作为京津冀典型特大城市之一,天
津市半城市化区县的发展与城镇化驱动机制
在京津冀都市圈有较强的代表性,且与长三
角珠三角地区的发展特征有巨大差异。本文
在既有研究的基础上优化指标体系,提出门
槛时间划定方法和发展模式分析方法,并将
其应用于天津市半城市化区县。分析结果显
示:天津市半城市化空间扩张经历了轴向缓
慢发展、圈层+轴向拓展、中郊蔓延以及远郊
辐射四大发展阶段;近远郊发展模式差异较
大,其中近郊以土地—综合—人口的快速迭
代增长模式为主,中远郊则以土地—人口(经
济)的缓慢波动发展模式为主。最后,结合分
析结果和实际发展路径对其发展机制与治理
瓶颈进行分析。 相似文献