Rapid estimation of an earthquake impact area using a spatial logistic growth model based on social media data

Rapid estimates of impact areas following large earthquakes constitute the cornerstone of emergency response scenarios.However,collecting information through traditional practices usually requires a large amount of manpower and material resources,slowing the response time.Social media has emerged as a source of real-time‘citizen-sensor data’for disasters and can thus contribute to the rapid acquisition of disaster information.This paper proposes an approach to quickly estimate the impact area following a large earthquake via social media.Specifically,a spatial logistic growth model(SLGM)is proposed to describe the spatial growth of citizen-sensor data influenced by the earthquake impact strength after an earthquake;a framework is then developed to estimate the earthquake impact area by combining social media data and other auxiliary data based on the SLGM.The reliability of our approach is demonstrated in two earthquake cases by comparing the detected areas with official intensity maps,and the time sensitivity of the social media data in the SLGM is discussed.The results illustrate that our approach can effectively estimate the earthquake impact area.We verify the external validity of our model across other earthquake events and provide further insights into extracting more valuable earthquake information using social media.

Numerical Study on the Impacts of Heterogeneous Reactions on Ozone Formation in the Beijing Urban Area

The air quality model CMAQ-MADRID （Community Multiscale Air Quality-Model of Aerosol Dynamics, Reaction, Ionization and Dissolution） was employed to simulate summer O3 formation in Beijing China, in order to explore the impacts of four heterogeneous reactions on O3 formation in an urban area. The results showed that the impacts were obvious and exhibited the characteristics of a typical response of a VOC-limited regime in the urban area. For the four heterogeneous reactions considered, the NO2 and HO2 heterogeneous reactions have the most severe impacts on O3 formation. During the O3 formation period, the NO2 heterogeneous reaction increased new radical creation by 30%, raising the atmospheric activity as more NO→NO2 conversion occurred, thus causing the O3 to rise. The increase of O3 peak concentration reached a maximum value of 67 ppb in the urban area. In the morning hours, high NO titration reduced the effect of the photolysis of HONO, which was produced heterogeneously at night in the surface layer. The NO2 heterogeneous reaction in the daytime is likely one of the major reasons causing the O3 increase in the Beijing urban area. The HO2 heterogeneous reaction accelerated radical termination, resulting in a decrease of the radical concentration by 44% at the most. O3 peak concentration decreased by a maximum amount of 24 ppb in the urban area. The simulation results were improved when the heterogeneous reactions were included, with the O3 and HONO model results close to the observations.

Assessment and impact of anthropogenic disturbances in protected areas of northern Togo

These days, human activities in the savanna and the remaining dry and riparian forests of the Sudanian ecoregions continue to have their impact. These anthropogenic practices are still the main cause of disturbances in these areas. In order to investigate and assess the importance of these disturbances, caused by people bordering on protected areas and to determine the relation between these activities and the environment in which they are carried out, 220 samples were selected in the three main protected areas of northern Togo. The investigation was mainly qualitative, considering the floristic sampling of this drought area; any anthropogenic activities observed were recorded. A simple investigative questionnaire about the activities of rural people in the reserved areas was distributed to individuals encountered in the study area. Each sample in the investigation ended with a site description of its ecologi- cal characterization, i.e., soil features, topography, fauna footprints, dominant plant species and GPS position; we also took photo- graphs of the site. Data processing was entirely based on descriptive statistics and a factor analysis. The results show that eight kinds of human activities, i.e., the use of pastures, tree cutting, bush fires, charcoal production, harvesting of plant material, fanning, honey harvesting and hunting, were noted to be serious disturbances to the integrity of the ecosystems. Among these disturbances, three are recurrent in all the sampled areas of which the use of pastures accounts for 31.88%, tree cutting for 30.35% and bush fires for 30.13%. Fire and pasture disturbances are closely linked and are responsible for the current features of the savanna area of the region. Tree cutting is more a direct function of the need for the production of wood fuel, generally used by city populations. Hunting, farm- ing and honey production are of lesser importance in the area and therefore, do not pose a significantly negative effect on the growth of fauna and flora. Knowledge of these disturbances in the context of requalification and a renewed demarcation of protected areas in Togo is essential for their sustainable management.

A numerical study of the impact of SST anomaly in the warm pool area on atmospheric circulation in winter

In this paper the impacts of the anomalous SST in the warm pool area of the Western Equatorial Pacific on the winter time circulation and the East Asian monsoon are studied by using the NCAR CCM. It is found that the abnormal heating in the warm pool area will change the strength and the position of the Walker Cell in the Equatorial Pacific and the anti-Walker Cell in the equatorial Indian Ocean. Both the Walker and anti-Walker Cells are strengthened. The local Hadley Cells over two hemispheres near the warm pool are also strengthened. The subtropical highs in two hemispheres become stronger and move poleward slightly. The westerly jets in the extratropical regions have similar changes as the subtropical highs. The winter monsoon in South-East Asia is weakened by the abnormal heating in the warm pool. The experiment also show that there are wave trains emanating from surrounding areas of the warm pool to the high latitudes, causing various changes in circulations and local weather.

Characteristics and Methods of Groundwater Environmental Impact Assessment in Mining Areas of Guizhou Province:A Case Study of Zhijin Area of Zhina Mining Area

In Guizhou Province,karst areas and springs are widely distributed,and hydrogeological conditions are complex in mining areas. Usually there are many hydrogeological units in a mining area,and the hydrogeological conditions are very different from that of most northern mining areas in China. In view of the uniqueness of mining areas in Guizhou Province,taking Zhijin area of Zhina mining area as an example,the planning characteristics of mining areas and characteristics of groundwater environment in Guizhou Province were analyzed firstly,and then the characteristics and key considerations of groundwater environmental impact assessment in mining areas of Guizhou Province were studied. For example,when the height of water flowing fractured zone,impact radius,and the amount of water resources affected are calculated,it is necessary to analyze and evaluate as many typical mines as possible. The impact on springs as the sources of residents＇ drinking water should be analyzed one by one.

郑州浅山区村落街巷微气候影响机制分析

【目的】探究村落街巷空间微气候的影响因素与调节机制,创造更加舒适的夏季微气候环境,减少能源消耗,提升农村居民生活品质。【方法】以郑州市浅山区典型村落的90个街巷样地为研究对象,通过实地调研和无人机测绘等方式采集数据,利用ENVI-met软件建立样地实况模型对微气候参数进行模拟,借助统计学分析方法探究街巷高宽比、街巷走向、植被覆盖度3项要素与街巷微气候的影响机制。【结果】1)高宽比(height-width ratio,H/W)主要通过降低平均太阳辐射温度(mean radiant temperature,MRT)来调节夏季街巷空间的微气候;植被覆盖度(fractional vegetation cover,FAC)主要通过增加相对湿度进而调节夏季街巷空间的微气候;而空气温度(air temperature,TA)、相对湿度(relative humidity,RH)、平均太阳辐射温度均会受到街巷走向的影响;2)通过极差分析可得,当高宽比达到1.1后,即可有效缩短街巷处于“极端”热应激等级的时间;3)在村内单位面积植被覆盖度≥10%时,通过和街巷高宽比结合设计的方式可最大程度地发挥植被增湿降温作用;4)南北走向(North-South direction,N-S)的街巷内夏季的空气温度、相对湿度、平均太阳辐射温度均优于东西走向(East-West direction,E-W)。【结论】街巷高宽比、街巷走向、植被覆盖度对郑州浅山区村落街巷微气候的影响机制各不相同,三者之间具有一定的关联性且存在最佳阈值。可从微气候的角度对村落街巷空间进行改造和设计,提升乡村人居环境品质的规划设计策略,为相同地理环境下的村落改造提供参考借鉴。

矿区生态环境调研评估与修复方案研究

以某矿区为例,对矿区水文环境、工程地质、基本设施等生态环境进行调研分析,结合调研结果预估矿山地质环境影响,分析矿区采矿活动对各类矿区地质环境因素所造成的影响。根据地质环境影响预测评估结果,实施矿区地质环境治理分区,介绍工程生态环境修复方案设计,为后续矿区生态环境修复方案设计,提供调研评估方法与修复设计方案参考。

BBNJ协定在国际海洋法上的制度创新

2023年在联合国总部通过的BBNJ协定是全球海洋治理的一个里程碑。该协定聚焦国际海洋法领域的重大和前沿问题,创设了规范海洋遗传资源的特殊法律制度、确立了适用于全球公海的海洋保护区制度、丰富了规范海洋活动的环境影响评价制度。为避免因不当介入国家间陆地或海洋争端而妨害协定的实施,BBNJ协定设计了若干条款,确保将协定排除适用于国家管辖海域或争议海域。上述成果填补了国际海洋法的许多空白,拓展了国际海洋法的调整对象,为发展海洋法律制度、推进全球海洋治理作出了贡献。

山区铁路隧道工程资源环境影响效应评估研究

山区地质复杂、环境敏感、生态脆弱,致使铁路隧道建设难度大,且在资源节约、环境保护等方面面临较高要求。绿色设计作为绿色建设的先行环节,对减少隧道建设对资源环境的扰动作用,达到资源节约、环境友好的目的起关键引领作用。为定量评估山区铁路隧道工程的资源环境影响效应、衡量隧道设计的绿色程度,提出一种山区铁路隧道工程资源环境影响效应分析方法。首先,基于“驱动力-状态-响应”模型(Driving force-State-Response,DSR),以隧道设计参数为驱动力指标、资源环境状况为状态指标、隧道设计措施为响应指标,构建山区铁路隧道工程资源环境影响效应评估指标体系,并建立各指标分级标准;其次,运用一种具有自学习自调整能力的支持向量回归模型(Support Vector Regression,SVR)对隧道工程的资源环境影响效应进行评估;再次,以驱动力指标和响应指标为分析对象,运用考虑指标间关联关系及叠加效应的敏感性分析法,甄别对隧道工程资源环境影响效应优化具有重要影响的隧道设计因素;最后,以某山区铁路隧道工程为例,得到该隧道工程的资源环境影响效应值为4.7157,对应等级为较好,表明该隧道工程绿色设计水平较好,资源集约节约利用较合理、环境保护力度较大,可为其他类似工况隧道工程的绿色设计提供借鉴。此外,分析结果显示,注浆加固效果是导致该隧道工程资源环境影响效应变化最敏感的因素,其次为清污分流比例,可着重从这2个方面进行优化设计,以实现隧道工程资源环境影响效应的进一步优化。研究结果验证了本文研究方法的适用性和可操作性,可为山区铁路隧道工程资源环境影响效应评估及明确隧道工程优化设计方向提供科学依据。

安百拓液压凿岩机活塞受力面积分析与三段法述评

搜集了11个安百拓双控式凿岩机和4个后控式凿岩机冲击活塞的直径数据,计算得到在凿岩机冲击运动周期中,回程与冲程活塞受力面积的比值范围。根据比值数据的分析,指出基于三段法理论的设计变量作为凿岩机性能评价指标的普适性较差。据此,本文强调了数据分析在凿岩机研究中的重要作用。文中还介绍了改进的三段法理论及其计算实例,论述了改进的三段法的优点与缺点。

“三农”领域高校智库建设现状及发展路径探析

“三农”领域高校智库在“三农”问题分析、决策拟定及政策工具弥补纠正等方面发挥着重要作用。为促进中国“三农”领域学术研究与智库研究有效对接,分析相关高校智库建设现状,总结其发展行为、运行机制、成果水平等方面及特点。研究发现,中国“三农”领域的高校智库建设主要依托一批专业化的研究团队和学术机构,在“三农”领域智库中数量占比最高且呈现快速增长趋势,并表现出强烈的地域性特征,在推动农业产业高质量发展方面发挥重要作用;但面临着服务乡村振兴的激励有限、协同合作能力有限、农业生产活动复杂性与农村调查公益性、成果实效水平不高和政策转化力度不够、资源及资金投入缺乏多元化与灵活性等困境。针对此,提出发挥涉农学科优势、推动成果评价制度改革、营造良好生态体系、畅通资政服务渠道、打造政产学研联盟共同体、构建“旋转门”机制、与新农村发展研究院协同建设等对策建议,以期对“三农”领域高校智库体系的建设与转型升级有所裨益,更好地满足新时期全面推进乡村振兴战略的智力需求。

跨境合作区的尺度重构与空间响应--以横琴为例

基于尺度重构理论,搭建尺度重构对空间影响的分析框架,并以横琴为例,从领域空间、制度建构、治理结构多维度协同入手,分析尺度重构不同阶段对空间的影响,探讨尺度不协调带来的空间治理问题以及尺度再重构下横琴空间规划响应的重点。研究认为,横琴空间演化的实质是通过尺度重构的渐进式调整、治理机制的优化来实现国家战略意图。在横琴新区建设时期,其多维度尺度关系相对复杂,存在领域空间模糊化、制度空间配置失衡、治理机制失效等问题;在横琴粤澳深度合作区建设时期,尺度再次上移,对领域空间、制度建构、治理结构进行了系统调整,尝试修正“尺度陷阱”问题。因此,在新一轮尺度重构下,横琴规划应当坚持制度设计的初心,创新空间标准,创建跨界包容共享的优质生活与就业场景,探索构建多元融合的“社会特区”。

高压喷嘴流动机理与结构优化设计研究

高压喷嘴作为高压水射流系统中的一个重要元件,其构造和特性直接影响高压水射流清洗系统性能的优劣,因此对高压喷嘴结构的研究具有非常重要的意义。文章通过对高压喷嘴进行结构设计、模型建立、数值模拟、结果分析,将靶面打击压强及打击面积作为主要的分析参数,对不同喷嘴结构和靶距下的高压水射流特性进行分析,得出最优的高压喷嘴结构以及打击距离。结果表明:渐缩形喷嘴的出口流量比锥形喷嘴出口流量增加了4.2%,比流线形喷嘴出口流量增加了1.6%;渐缩形喷嘴冲击靶距由50.68 mm减小到10 mm时,射流大于10 MPa的平均动压力值由27.2 MPa增加到31.9 MPa,射流大于40 MPa的平均动压力值由47.9 MPa增加到66.9 MPa;对应射流靶距为30 mm时,大于10 MPa的有效冲击面积最大,可达到8.3 cm^(2)。

120 t转炉顶底复吹过程多相流数值模拟研究

以120 t五孔氧枪顶底复吹转炉为原型,基于Fluent数值模拟,对多组不同氧枪枪位与底吹气体流量方案进行建模计算,分析了五孔喷头顶吹超音速射流行为,以及不同方案下熔池冲击面积及冲击深度的变化规律。模拟结果与前人实测结果吻合,证明了模拟的准确性。模拟结果表明,由于顶底复吹作用,速度集中在钢液面附近,顶吹和底吹气流周围的区域钢液流速变慢;随着氧枪高度不断升高,冲击深度逐渐减小,冲击面积先增大后减小;当氧枪高度1.8 m时熔池冲击面积最大,单孔底吹流量为60 m^(3)/h,底吹效果最好。

甘肃民族地区旅游影响感知对国家认同感的影响评价--以临夏回族自治州八坊十三巷景区为例

旅游目的地居民对国家认同感的持续提升是民族地区旅游业可持续发展的重要目标。文章以临夏州八坊十三巷景区为例,从居民旅游影响感知视角,探讨了旅游发展对当地居民国家认同感的影响,得出以下结论:(1)从旅游影响对国家认同感的影响感知来看,民族地区旅游目的居民对当地旅游发展带来的国家认同感更为敏感;(2)从旅游影响对国家认同感的影响评价来看,民族地区居民的旅游影响感知对国家认同感的综合影响评价较高。旅游业的发展进一步增强了人们的民族自豪感、文化自信以及对国家的功能依赖。

基于MaxEnt模型预测湖南省榧树适宜分布区

【目的】榧树Torreya grandis是我国特有的珍稀经济树种,预测榧树在湖南省的适宜分布区,探究影响其分布的主导环境因子,有助于其保护策略的制定和开发利用适宜地的选择。【方法】以湖南省193个野外调查榧树分布点为基础数据源,选取了22个影响其分布的环境变量,运用MaxEnt最大熵模型和ArcGIS10.7软件,分析影响其分布的主导环境因子,预测其在湖南省的适宜分布区。【结果】1)ROC曲线下训练数据集10次交叉验证拟合的平均AUC值为0.914,测试数据集10次交叉验证拟合的平均AUC值为0.867,标准差为0.074,模型预测精度可靠。2)限制榧树当前潜在适生区分布的4个关键因素依次是海拔、坡度、最干季平均温度以及最热季降水量,其百分比贡献率依次为29.40、16.90、8.60、7.30;置换重要性依次为53.30、14.60、5.70、6.50。43)榧树在湖南省的适生区总面积为9.114×10 km^(2),高适生区、中适生区、低适生区面积分别为0.872×10^(4)、2.659×10^(4)、5.583×10^(4) km^(2);榧树适生区主要集中在湘中、西、东南地区,高、中适生区集中分布在邵阳北部、南部、西南部,益阳西南部,永州中南部,娄底西北部以及怀化中南部。【结论】地形、气候等因子综合影响着湖南省榧树的地理分布格局,邵阳、益阳、永州、娄底、怀化等地区中,海拔较低、地势相对平缓、气候凉爽的溪谷地区可能适合榧树的引种栽培。

基于空耦冲击回波法的饰面瓷砖层间脱空识别研究

针对饰面瓷砖脱空掉落的现象,建立了空气-饰面瓷砖层间脱空有限元模型,分析了钢球半径、激励速度以及信号采集位置等因素对饰面瓷砖层间脱空检测效果的影响,确定了最优值,然后利用特征识别参数对饰面瓷砖粘结层的脱空程度进行评估,并开展足尺试验对有限元模型的有效性进行验证。结果表明:钢球半径建议取9 mm,激励速度建议取1 m·s^(-1),信号采集点与激励点的横向距离不宜小于60 mm,垂向距离取5 mm;黏结层脱空会使冲击回波信号加强。因此,时域图中的信号波动性增强、衰减速度减缓,频域图中的声压级增大,主频段前移并分化为代表结构整体振动和局部振动的两个频段;并且随着脱空程度的增加,频域面积增大,通过计算频域面积可有效评估饰面瓷砖黏结层的脱空状况。研究结果为饰面瓷砖的无损检测提供了参考。

三峡库区弯曲河段大偏角船桥碰撞力分析

为研究船舶在大角度和高流速下与大跨度斜拉桥发生的碰撞响应,结合国内外相关规范对船桥碰撞中最大撞击力计算方法和撞击方式,对内河航运过程中可能发生的碰撞角度和方式进行分析,并以重庆外环江津长江大桥作为依托工程,采用附加质量法建立了7 000 t级散货船和等比例斜拉桥模型,计算了船舶在四种通航水位下的正撞、侧撞和漂撞的最大撞击力,比较各规范的计算值与数值模拟结果,对不同情况下的计算结果进行对比研究。结果表明,国内外各规范更适用于船舶撞击桥塔,撞击点位于桥梁承台时最大撞击力将远高于规范计算值;在船舶与桥梁正面碰撞中,《美国公路桥梁设计规范》(American Association of State Highway and Transportation Officials, AASHTO)计算值与模拟值吻合程度高;在侧撞中,尤其在撞击角度为10°~25°时,建议采用《公路桥梁抗撞设计规范》;船舶漂撞桥塔产生的撞击力大约为正向撞击的1/4,该情况可采用《铁路桥涵设计规范》进行计算。多角度船桥碰撞研究结果可为三峡库区高变幅水位下船桥碰撞安全风险评估和桥梁抗撞设计提供参考。