Asymmetric Relationship between the Meridional Displacement of the Asian Westerly Jet and the Silk Road Pattern

In previous work, a significant relationship was identified between the meridional displacement of the Asian westerly jet （JMD） and the Silk Road Pattern （SRP） in summer. The present study reveals that this relationship is robust in northward JMD years but absent in southward JMD years. In other words, the amplitude of the SRP increases with northward displacement of the jet but shows little change with southward displacement. Further analysis indicates that, in northward JMD years, the Rossby wave source （RWS） anomalies, which are primarily contributed by the planetary vortex stretching, are significantly stronger around the entrance of the Asian jet, i.e., the Mediterranean Sea-Caspian Sea area, with the spatial distribution being consistent with that related to the SRP. By contrast, in southward JMD years, the RWS anomalies are much weaker. Therefore, this study suggests that the RWS plays a crucial role in inducing the asymmetry of the JMD-SRP relationship. The results imply that climate anomalies may be stronger in strongly northward-displaced JMD years due to the concurrence of the JMD and SRP, and thus more attention should be paid to these years.

Two Modes of the Silk Road Pattern and Their Interannual Variability Simulated by LASG/IAP AGCM SAMIL2.0

In this study, two modes of the Silk Road pattern were investigated using NCEP2 reanalysis data and the simulation produced by Spectral Atmospheric Circulation Model of IAP LASG, Version 2 （SAMIL2.0） that was forced by SST observation data. The horizontal distribution of both modes were reasonably reproduced by the simulation, with a pattern correlation coefficient of 0.63 for the first mode and 0.62 for the second mode. The wave train was maintained by barotropic energy conversion （denoted as CK） and baroclinic energy conversion （denoted as CP） from the mean flow. The distribution of CK was dominated by its meridional component （CKy） in both modes. When integrated spatially, CKx was more efficient than its zonal component （CKx） in the first mode but less in the second mode. The distribution and efficiency of CK were not captured well by SAMIL2.0. However, the model performed reasonably well at reproducing the distribution and efficiency of CP in both modes. Because CP is more efficient than CK, the spatial patterns of the Silk Road pattern were well reproduced. Interestingly, the temporal phase of the second mode was well captured by a single-member simulation. However, further analysis of other ensemble runs demonstrated that the successful reproduction of the temporal phase was a result of internal variability rather than a signal of SST forcing. The analysis shows that the observed temporal variations of both CP and CK were poorly reproduced, leading to the low accuracy of the temporal phase of the Silk Road pattern in the simulation.

Comparison between the interannual and decadal components of the Silk Road pattern

The Silk Road pattern（SRP）, which is a teleconnection pattern along the Asian upper-tropospheric westerly jet in summer, exhibits both interannual and decadal variabilities. Through the nineyear Gaussian filtering method and regression analyses, this study compares the interannual and decadal components of the SRP. The results indicate that the interannual SRP corresponds to a well-organized wave train of alternate cyclonic and anticyclonic anomalies across the Eurasian continent along the Asian westerly jet, resulting in a similar wave-like pattern of cold and warm surface temperature anomalies. This pattern of temperature anomalies differs from that associated with the original SRP, which is characterized by warmer or cooler temperatures mainly over Europe–West Asia and Northeast Asia, depending on the phase of the SRP. On the other hand, the decadal SRP shows a similar pattern to the interannual one from Europe to Central Asia, but the meridional wind anomalies tend to be weak over East Asia. These circulation anomalies are responsible for the significant temperature anomalies over Europe–West Asia and Northeast Asia but weak anomalies between these two domains.

Teleconnection between Sea Ice in the Barents Sea in June and the Silk Road,Pacific–Japan and East Asian Rainfall Patterns in August

In contrast to previous studies that have tended to focus on the influence of the total Arctic sea-ice cover on the East Asian summer tripole rainfall pattern, the present study identifies the Barents Sea as the key region where the June sea-ice variability exerts the most significant impacts on the East Asian August tripole rainfall pattern, and explores the teleconnection mechanisms involved. The results reveal that a reduction in June sea ice excites anomalous upward air motion due to strong near-surface thermal forcing, which further triggers a meridional overturning wave-like pattern extending to midlatitudes.Anomalous downward motion therefore forms over the Caspian Sea, which in turn induces zonally oriented overturning circulation along the subtropical jet stream, exhibiting the east–west Rossby wave train known as the Silk Road pattern. It is suggested that the Bonin high, a subtropical anticyclone predominant near South Korea, shows a significant anomaly due to the eastward extension of the Silk Road pattern to East Asia. As a possible descending branch of the Hadley cell, the Bonin high anomaly ultimately triggers a meridional overturning, establishing the Pacific–Japan pattern. This in turn induces an anomalous anticyclone and cyclone pair over East Asia, and a tripole vertical convection anomaly meridionally oriented over East Asia. Consequently, a tripole rainfall anomaly pattern is observed over East Asia. Results from numerical experiments using version 5 of the Community Atmosphere Model support the interpretation of this chain of events.

Connection between the Silk Road Pattern in July and the Following January Temperature over East Asia

This study investigates a cross-seasonal influence of the Silk Road Pattern（SRP）in July and discusses the related mechanism.Both the reanalysis and observational datasets indicate that the July SRP is closely related to the following January temperature over East Asia during 1958/59–2001/02.Linear regression results reveal that,following a higher-than-normal SRP index in July,the Siberian high,Aleutian low,Urals high,East Asian trough,and meridional shear of the East Asian jet intensify significantly in January.Such atmospheric circulation anomalies are favorable for northerly wind anomalies over East Asia,leading to more southward advection of cold air and causing a decrease in temperature.Further analysis indicates that the North Pacific sea surface temperature anomalies（SSTAs）might play a critical role in storing the anomalous signal of the July SRP.The significant SSTAs related to the July SRP weaken in October and November,re-emerge in December,and strengthen in the following January.Such an SSTA pattern in January can induce a surface anomalous cyclone over North Pacific and lead to dominant convergence anomalies over northwestern Pacific.Correspondingly,significant divergence anomalies appear,collocated in the upper-level troposphere in situ.Due to the advection of vorticity by divergent wind,which can be regarded as a wave source,a stationary Rossby wave originates from North Pacific and propagates eastward to East Asia,leading to temperature anomalies through its influence on the large-scale atmospheric circulation.

Road Centrality and Landscape Spatial Patterns in Wuhan Metropolitan Area,China

Road network is a corridor system that interacts with surrounding landscapes,and understanding their interaction helps to develop an optimal plan for sustainable transportation and land use.This study investigates the relationships between road centrality and landscape patterns in the Wuhan Metropolitan Area,China.The densities of centrality measures,including closeness,betweenness,and straightness,are calculated by kernel density estimation(KDE).The landscape patterns are characterized by four landscape metrics,including percentage of landscape(PLAND),Shannon′s diversity index(SHDI),mean patch size(MPS),and mean shape index(MSI).Spearman rank correlation analysis is then used to quantify their relationships at both landscape and class levels.The results show that the centrality measures can reflect the hierarchy of road network as they associate with road grade.Further analysis exhibit that as centrality densities increase,the whole landscape becomes more fragmented and regular.At the class level,the forest gradually decreases and becomes fragmented,while the construction land increases and turns to more compact.Therefore,these findings indicate that the ability and potential applications of centrality densities estimated by KDE in quantifying the relationships between roads and landscapes,can provide detailed information and valuable guidance for transportation and land-use planning as well as a new insight into ecological effects of roads.

Factors and Pattern of Injuries Associated with Road Traffic Accidents in Hilly District of Nepal

Introduction: In 21st century, road traffic accidents (RTA) are considered as increasing epidemic of non-communicable disease which is abandoned and needs special attention to prevent them. The aim of this study was to assess the factors and pattern of injuries associated with road traffic accidents. Methods: A cross sectional study was conducted among 112 RTA victims and 56 drivers in Palpa District of Nepal. The association of factors and pattern of injuries with exposure to accidents was assessed using Fisher’s exact test. Bivariate logistic regression examined the association between driving and socio-demographics factors and exposure to road accidents. Results: Of 112 RTA victims, 50% were in the age group of 21 to 40 years and 71.4% were male. Drivers who were in the age less than or equal to 30 years were more likely (OR: 3.6;95% CI: 1.0, 14.3) to expose to an accident than those who were above 30 years. Similarly, those having driving speed less than 40 km/hr were less likely to expose to an accident than those with speed 40 - 60 km/hr (OR: 6.0;95% CI: 0.8, 73.5) and those with speed more than 60 km/hr (OR 7.8;95% CI: 1.0, 100.1). Moreover, the driving experience was also found positively associated (OR: 5.6;95% CI: 1.1, 35.5) with the exposure to an accident. Conclusion: Being in younger age group, male gender, morning time, the driving speed, driving experiences, and driving hours on the road were positively associated with RTA. The efforts should be made to enforce laws in control of speed targeting experienced drivers and those with younger age groups.

Safer Design and Less Cost Operation for Low-Traffic Long-Road Illumination Using Control System Based on Pattern Recognition Technique

The paper covers analysis and investigation of lighting automation system in low-traffic long-roads. The main objective is to provide optimal solution between expensive safe design that utilizes continuous street lighting system at night for the entire road, or inexpensive design that sacrifices the safety, relying on using vehicles lighting, to eliminate the problem of high cost energy consumption during the night operation of the road. By taking into account both of these factors, smart lighting automation system is proposed using Pattern Recognition Technique applied on vehicle number-plates. In this proposal, the road is sectionalized into zones, and based on smart Pattern Recognition Technique, the control system of the road lighting illuminates only the zone that the vehicles pass through. Economic analysis is provided in this paper to support the value of using this design of lighting control system.

“一带一路”背景下广东与东盟国家贸易格局演变及影响因素分析

在“一带一路”倡议下,广东与东盟国家之间的贸易关系呈现出新的发展机遇,因此对双边贸易进行研究具有重要的价值。本文运用贸易强度指数、HM指数、贸易引力模型分析了在“一带一路”背景下广东与东盟十国贸易格局的时空演变及其影响因素。研究结果表明:广东与东盟国家之间的贸易规模不断扩大,双边贸易差额逐渐减小;马来西亚成为广东最重要的贸易伙伴,其次是泰国,新加坡的贸易伙伴地位有所下降;广东与东盟国家的进出口贸易紧密程度越来越强,广东出口对东盟整体市场的依赖性很小但呈现逐渐增强的趋势;广东省人均GDP、东盟各国人均GDP和人口规模、贸易自由度对广东与东盟国家双边贸易具有正向推动作用,广东省人口规模、首都(府)间距离和加权平均关税对广东与东盟国家双边贸易具有反向阻碍作用。

江、河、海交融影响下的扬州古城格局演进研究

扬州位于运河和长江交汇处,长江岸线、运河水系的变迁及海上贸易的影响,对扬州古城格局演进产生了重大作用。运河水系和长江岸线的变迁,推动扬州古城从闾里制度格局下的“单城”,发展为坊市制度及其后的“多城”。随着古代扬州的水环境变迁及工商业贸易的繁荣,扬州古城形态历经从秦至隋时期的“口”字形、唐至元时期的“吕”字形至明清时期的“明”字形的格局变化,以及自唐元时期的“南北纵向”至明清时期的“东西横向”生长方向变化;城市功能也从封闭型防御功能为主逐步演进为开放型商贸功能为主,并呈现“江、河、海共生型”扬州古城空间格局演进特点。

鄱阳湖生态经济区建设用地扩张对耕地景观破碎化的影响

为分析鄱阳湖生态经济区耕地景观与建设用地扩张之间的关系,利用形态学空间格局分析法研究2000-2020年耕地景观破碎化的形态学特点,同时运用外溢效应分析、景观格局指数分析、地理加权回归等模型方法,探究建设用地扩张对耕地景观破碎化的影响。结果表明:2000-2020年间耕地景观破碎化程度加强,核心区面积减少强度由1.33%提高到6.27%,并表现出由平原地区向山地丘陵区加强的地域性差异,且建设用地扩张会导致耕地景观破碎化;建设用地占用耕地的面积由268.60 km2增加到1 003.26 km2,主要发生在路网成熟的地区;建设用地扩张对耕地的外溢效应逐渐增强,在路网成熟地区更显著;建设用地扩张对耕地景观破碎化有较强的正向影响,道路建设对这种影响有强化作用,同时,耕地景观破碎化表现出随道路缓冲距离的减小而加强的阶梯性差异。研究表明,耕地景观破碎化程度受地形和建设用地扩张的影响显著,耕地景观破碎化现象主要发生在地势起伏大或建设用地密集、路网成熟的地区。

神农架国家公园野生动物对道路的时空适应动态研究

理解野生动物对人为干扰的响应有助于更好地制定野生动物保护和人为干扰管理策略。本研究基于2023年5-10月在神农架国家公园神农顶区域的红外相机监测数据,识别道路对物种多样性分布的影响,分析主要有蹄类相对多度与日活动节律,探讨野生动物对道路的时空响应,并与2014年红外相机数据比较以探究野生动物对道路的适应动态。结果表明:①2023年红外相机共记录到兽类5目14科24种,鸟类5目16科39种。②道路对物种多样性的分布具有显著影响,道路影响的阈值约为50 m和150 m。③野生动物从时间和空间两个维度回避人类活动高峰且回避程度具有物种特异性,梅花鹿表现为空间不回避、时间回避;小麂和中华斑羚表现为不同程度的时空回避,空间回避距离约为50 m。④在道路50 m范围内拍摄到豹猫、林麝等,梅花鹿、小麂、中华斑羚的相对多度较10年前更高。研究显示,野生动物通过调节自身活动节律适应道路干扰,对道路表现出一定的适应性。研究结果可为国家公园道路等人为活动管理措施的制定提供科学依据。

风流扰动下露天矿土质路面粉尘运移规律研究

为降低露天矿土质路面粉尘质量浓度,提高清洁生产水平,采用气固两相流理论,建立粉尘颗粒起动模型,分析粉尘起动风速及变化规律,利用实验研究进行验证,并确立粉尘运移规律以及运动形式,选取正交实验极差分析各因素对起尘量影响显著性。研究结果表明:粉尘起动风速与粉尘粒径、含水率、负荷均有函数关系;起尘量在粒径、含水率、负荷、风速4种因素下呈现不同变化规律,与粒径、风速均呈非线性关系,与含水率呈负相关,与粉尘负荷呈正相关,影响显著性为:粒径>负荷>风速>含水率;粉尘运动形式与风速和粒径相关,在5 m/s风速下,(0,75]μm粒径粉尘易做悬浮运动,(75,500]μm粒径粉尘易做跳跃运动,(500,1000]μm粒径粉尘易做蠕移运动。研究结果可为降尘措施提供理论指导。

共玉高速公路路基下伏多年冻土时空演变特征及影响因素

为分析青藏高原高速公路路基下伏多年冻土的时空演变特征,并探讨新建路基路面结构和自然环境因素对路基下伏多年冻土退化的影响程度,以共玉高速公路穿越多年冻土区南界段为例,利用ArcGIS栅格单元属性分析方法对研究区内公开的气候、地形及钻芯数据进行深入挖掘;分析了不同高程、坡度、坡向、归一化植被指数(NDVI)、年平均气温(MAT)、年平均地温(MAGT)、平均年降雨量(MAP)、年平均湿度(MAH)和新建路基路面结构对高速公路路基下伏多年冻土时空演变特征的影响。结果表明:新建路基路面结构对路基下伏多年冻土退化的影响程度为自然环境因素的1.23倍;2011—2019年沿线多年冻土退化呈现出一定的空间异质性,在多年冻土快速和低速退化区内,影响多年冻土退化速度的主要因素分别为MAGT和MAH;影响整个研究区多年冻土退化速度的主要因素为MAGT;2011—2019年高速公路路基下伏多年冻土退化速度为36 cm/a,分别为同期青藏铁路和青藏公路的8倍和2.32倍,为同期同区位G214共玉高速公路的1.83倍。建议青藏高原多年冻土区高速公路选线按无多年冻土分布、有多年冻土赋存的高海拔阴坡、低海拔阴坡、高海拔阳坡和低海拔阳坡的位置分布依次选择,且当路线走向定于后3种情形时,需对路基采取相应的保护冻土措施。

近几十年丝绸之路遥相关对中国夏季气温的影响

为分析近几十年丝绸之路遥相关对中国夏季气温的影响及可能机理,基于1961-2020年CN05.1高分辨格点气温资料和ERA5大气再分析资料,采用经验正交分解、回归分析和相关分析等统计诊断方法分析丝绸之路遥相关对中国夏季气温的影响及可能机理,结果表明:(1)丝绸之路遥相关主要沿亚洲急流自西向东传播,呈显著的“-+-+”分布,其活动中心主要位于里海、巴尔喀什湖和中国北方地区,并存在明显的年际变化和年代际变化。中国夏季气温整体上呈一致的变化趋势,其中20世纪60-80年代由暖到冷,90年代后又明显升温。(2)除新疆西部和西藏西部、东北地区西部及江淮地区为负相关分布外,夏季丝绸之路遥相关与同期中国大部分地区气温之间为显著的正相关关系。(3)丝绸之路遥相关可通过影响北半球对流层中高层位势高度、垂直速度和涡度平流等环流因子导致中国夏季气温异常。具体表现为受丝绸之路遥相关影响产生的位势高度正异常有利于晴好天气的维持,同时对流层中高层受负涡度平流控制,以下沉运动为主,导致中国夏季气温异常升高。

基于sDNA的路网演变及其对景观格局的影响

为探讨路网空间结构对景观格局的影响,以招远市为例,获取2009—2018年路网数据和土地利用数据,利用sDNA模型和路网密度计算方法,计算道路接近度和路网密度,作为道路网络结构评价指标;选取PD、ED、LPI、LSI、AI、SHDI等指数构建景观格局评价体系,从而分析城市道路网络空间结构对景观格局的影响。结果表明,2009—2018年招远市道路接近度和路网密度自中心向周围呈递减态势;研究区景观呈多样性、复杂性、破碎化发展态势,道路接近度与景观格局指数的相关性更高,因此在表征景观格局变化时,道路接近度比路网密度更加准确。

加快构建辽宁“一体两翼”对外开放新格局

辽宁是东北亚开放的窗口和“一带一路”建设的重要节点,加快构建“一体两翼”对外开放新格局是辽宁深化改革、扩大开放、实现高质量发展和全面振兴全方位振兴的重要举措。从贸易开放、资金开放、技术开放、社会开放四个维度构建“一体两翼”对外开放效果评价体系,采用因子分析法对2021年我国内地31个省份对外开放度进行评价,结果显示:辽宁对外开放度在全国处于较低水平,外贸外资因子、教育文化因子和旅游因子得分显著低于广东、上海和浙江,是影响辽宁对外开放水平的主要因素。从外资外贸、教育文化、旅游方面的主因子视角和对接国际高标准规则优化营商环境,加强区域合作开放平台建设,完善国际合作交通网络等政策方面,提出加快构建辽宁“一体两翼”对外开放新格局的对策建议。

丝绸之路视域下唐代纺织品中鸟衔花纹样的起源与形式流变

文章以唐代纺织品中的鸟衔花纹样为研究对象,通过历史文献与考古实物等资料对其溯源。梳理丝绸之路打通后西方鸟衔花纹样的传播,并分析其传入唐代后的形式演变。研究表明,唐代纺织品中的鸟衔花纹样因受到了西方含绶鸟纹样题材、纬线显花织造技术等因素影响而形成。并经历了模仿、改造、定型三个发展阶段,完成从呆板程式向传神自由转变的本土化进程,该纹样在唐代的演变可进一步细分为“团窠对鸟”和“足踏花台”的双线发展模式。

教师教育现代化转型之路

作为以中国式现代化全方位推进国家兴、民族兴的基础工程,建成教育强国,必然离不开教育高质量发展,更离不开教师教育现代化转型。教师教育现代化转型既是满足教育高质量发展和中国式教育现代化发展的需要,也是落实教育数字化战略、实现个性化育人的需要。从我国教育国情与实践上来看,教师教育现代化转型的内涵包括以立德树人为本源、以守正创新为原则、以建成教育强国为目标。在教师教育现代化转型之路上,应从“教师教育的政策取向、教师教育的模式建构、教师教育的知识创新”等三个方面进行探索,以培养造就高素质专业化教师队伍。

两种道路网格网模式识别方法比较研究

基于“数据密集型范式”的研究思路,设计了两种格网模式道路识别方法。一种是基于统计实验区域的道路相交角的方法,另外一种是基于统计实验区域道路网眼格网单元矩形度的方法。经过实验验证,两种方法效果均较好,且易于运用于工程实践。