Spatiotemporal pattern of climate change in the China-Myanmar Economic Corridor from 1901 to 2018

The China-Myanmar Economic Corridor(CMEC) is an important part of China's Belt and Road Initiative and an important area for global ecology and biodiversity. In this study, the annual and seasonal spatiotemporal patterns of temperature and precipitation in the CMEC over the past century were investigated using linear tendency estimation, the Mann-Kendall mutation test, the T-test, and wavelet analysis based on the monthly mean climatic data from 1901 to 2018 released by the Climatic Research Unit(CRU) of the University of East Anglia, UK. The results show that the CMEC demonstrated a trend of warming and drying over the past 100 years, and the rate of change in Myanmar was stronger than that in Yunnan Province of China. The warming rate was 0.039 ℃/10a. Precipitation decreased at a rate of -6.1 mm/10a. From the perspective of spatial distribution, temperature was high in the central and southern, low in the north of the CMEC, and the high-temperature centers were mainly distributed in the southern plain and river valley. Precipitation decreased from west to east and from south to north of the CMEC. From the perspective of the rate of change, warming was stronger in central and northern CMEC than in southern and northeastern CMEC. The rate of precipitation decline was stronger in the central and western regions than in the eastern region. This study provides a scientific reference for the CMEC to address climate change and ensure sustainable social and economic development and ecological security.

Dynamic response of mountain tunnel,bridge,and embankment along the Sichuan-Tibet transportation corridor to active fault based on model tests

The Sichuan-Tibet transportation corridor is prone to numerous active faults and frequent strong earthquakes.While extensive studies have individually explored the effect of active faults and strong earthquakes on different engineering structures,their combined effect remains unclear.This research employed multiple physical model tests to investigate the dynamic response of various engineering structures,including tunnels,bridges,and embankments,under the simultaneous influence of cumulative earthquakes and stick-slip misalignment of an active fault.The prototype selected for this study was the Kanding No.2 tunnel,which crosses the Yunongxi fault zone within the Sichuan-Tibet transportation corridor.The results demonstrated that the tunnel,bridge,and embankment exhibited amplification in response to the input seismic wave,with the amplification effect gradually decreasing as the input peak ground acceleration(PGA)increased.The PGAs of different engineering structures were weakened by the fault rupture zone.Nevertheless,the misalignment of the active fault may decrease the overall stiffness of the engineering structure,leading to more severe damage,with a small contribution from seismic vibration.Additionally,the seismic vibration effect might be enlarged with the height of the engineering structure,and the tunnel is supposed to have a smaller PGA and lower dynamic earth pressure compared to bridges and embankments in strong earthquake zones crossing active faults.The findings contribute valuable insights for evaluating the dynamic response of various engineering structures crossing an active fault and provide an experimental reference for secure engineering design in the challenging conditions of the Sichuan-Tibet transportation corridor.

The changes in the annual distribution of mountain runoff during the period of 1965-2018 in Hexi Corridor,Northwest China

The annual distribution characteristics of river runoff in arid regions have significant implications for water resource stability and management.Based on the mountain runoff data from 1965 to 2018,this study examines the annual change characteristics of monthly runoff of the Shiyang River Basin,Heihe River Basin,and Shule River Basin in the Hexi Corridor,Northwest China.Many indexes are used and analyzed,including the coefficient of variance,the complete regulation coefficient,the concentration degree and concentration period,the magnitude of change,the skewness coefficient,and the kurtosis coefficient of the annual distribution curves.The results reveal the following:(1)The inhomogeneity of annual runoff distribution in the Taolai River and the rivers to the west of it,except the Shiyou River,show an increasing trend.Conversely,the inhomogeneity of the rivers to the east of the Taolai River generally show a downward trend,but the coefficient of variance value is still very high.(2)In the Shiyang River Basin,the annual distribution of the concentration period is characterized by a relatively discrete pattern.Conversely,the Heihe River Basin exhibits a relatively concentrated pattern,and the distribution pattern of the Shule River Basin is quite different.Notably,all concentration periods in the three basins have shifted backward after the 2000s.(3)The Shiyang River Basin exhibits disordered annual distribution curves of runoff in different years.In contrast,the Heihe River Basin presents a typical‘single-peak’pattern with a prominent right-skewed.The Shule River Basin has regular distribution curves,with a gradually significant‘double-peak’pattern from east to west.Overall,there has been a slight change in runoff in the Shiyang River Basin,while the Heihe River Basin and Shule River Basin have experienced significant increases in runoff.The annual distribution curves of runoff in the Liyuan River and the rivers to the east of it exhibit a gentle peak pattern,and the appearance probability of extreme runoff during the year is low.Conversely,the rivers to the west of the Liyuan River,excluding the Danghe River,display a sharp peak and thick tail pattern,indicating that the appearance probability of extreme runoff during the year is high.These findings have practical implications for the planning and management of water resources in the Hexi Corridor.Moreover,they provide a solid foundation for predicting future changes in regional water resources.

Empirical Bayes Absolute Error Loss Estimation for Parameter of One-Side Truncation Distribution Families

In this paper we propose an absolute error loss EB estimator for parameter of one-side truncation distribution families. Under some conditions we have proved that the convergence rates of its Bayes risk is o, where 0<λ,r≤1,Mn≤lnln n (for large n),Mn→∞ as n→∞.

One-sided empirical Bayes test for location parameter in Gamma distribution

In this paper, we devote to constructing the one-sided empirical Bayes(EB) test for the location parameter in the Gamma distribution by nonparametric method. Under some mild conditions, we prove that the EB test is asymptotically optimal with the rate of the order O(n^(-δs/(2s+1))), where 1/2 ≤ δ < 1 and s > 1 is a given natural number. An example is also given to illustrate that the conditions of the main theorems are easily satisfied.

An Efficient Second-Order Convergent Scheme for One-Side Space Fractional Diffusion Equations with Variable Coefficients

In this paper,a second-order fnite-diference scheme is investigated for time-dependent space fractional difusion equations with variable coefcients.In the presented scheme,the Crank-Nicolson temporal discretization and a second-order weighted-and-shifted Grünwald-Letnikov spatial discretization are employed.Theoretically,the unconditional stability and the second-order convergence in time and space of the proposed scheme are established under some conditions on the variable coefcients.Moreover,a Toeplitz preconditioner is proposed for linear systems arising from the proposed scheme.The condition number of the preconditioned matrix is proven to be bounded by a constant independent of the discretization step-sizes,so that the Krylov subspace solver for the preconditioned linear systems converges linearly.Numerical results are reported to show the convergence rate and the efciency of the proposed scheme.

Potential seismic landslide hazard and engineering effect in the Ya’an-Linzhi section of the Sichuan-Tibet transportation corridor, China

The Sichuan-Tibet transportation corridor is located at the eastern margin of the Qinghai-Tibet Plateau,where the complex topography and geological conditions,developed geo-hazards have severely restricted the planning and construction of major projects.For the long-term prevention and early control of regional seismic landslides,based on analyzing seismic landslide characteristics,the Newmark model was used to carry out the potential seismic landslide hazard assessment with a 50-year beyond probability 10%.The results show that the high seismic landslide hazard is mainly distributed along large active tectonic belts and deep-cut river canyons,and are significantly affected by the active tectonics.The low seismic landslide hazard is mainly distributed in the flat terrain such as the Quaternary basins,broad river valleys,and plateau planation planes.The major east-west linear projects mainly pass through five areas with high seismic landslide hazard:Luding-Kangding section,Yajiang-Xinlong(Yalong river)section,Batang-Baiyu(Jinsha river)section,Basu(Nujiang river)section,and Bomi-Linzhi(eastern Himalaya syntaxis)section.The seismic action of the Bomi-Linzhi section can also induce high-risk geo-hazard chains such as the high-level glacial lake breaks and glacial debris flows.The early prevention of seismic landslides should be strengthened in the areas with high seismic landslide hazard.

The Best m-Term One-Sided Approximation of Besov Classes by the Trigonometric Polynomials

In this paper, we continue studying the so called best m-term one-sided approximation and Greedy-liked one-sided ap- proximation by the trigonometric polynomials. The asymptotic estimations of the best m-terms one-sided approximation by the trigonometric polynomials on some classes of Besov spaces in the metricLp(Td(1≤p≤∞ are given.

Variation Inequalities for the Commutators of One-Sided Calderón-Zygmund Singular Integrals with Lipschitz Functions

In this paper, we establish the weighted Lp (1 < p < ∞) boundedness of variation operator for the commutators generated by one-sided Calderón-Zygmund singular integrals with Lipschitz functions.

New Approach to Observer-Based Finite-Time H_(∞)Control of Discrete-Time One-Sided Lipschitz Systems with Uncertainties

This paper investigates the finite-time H_(∞)control problem for a class of nonlinear discrete-time one-sided Lipschitz systems with uncertainties.Using the one-sided Lipschitz and quadratically inner-bounded conditions,the authors derive less conservative criterion for the controller design and observer design.A new criterion is proposed to ensure the closed-loop system is finite-time bounded(FTB).The sufficient conditions are established to ensure the closed-loop system is H_(∞)finite-time bounded(H_(∞)FTB)in terms of matrix inequalities.The controller gains and observer gains are given.A numerical example is provided to demonstrate the effectiveness of the proposed results.

Development characteristics and failure modes of reactivated ancient landslides in the Sichuan–Tibet transportation corridor,China

The risk of reactivated ancient landslides in the Sichuan–Tibet transportation corridor in China is significantly increasing,primarily driven by the intensification of engineering activities and the increased frequency of extreme weather events.This escalation has resulted in a considerable number of fatalities and extensive damage to critical engineering infrastructure.However,the factors contributing to the reactivation and modes of destruction of ancient landslides remain unknown.Therefore,it is imperative to systematically analyze the developmental characteristics and failure modes of reactivated ancient landslides to effectively mitigate disaster risks.Based on a combination of data collection,remote sensing interpretation,and field investigations,we delineated the developmental attributes of typical ancient landslides within the study area.These attributes encompass morphological and topographic aspects,material composition,and spatial structure of ancient landslides.Subsequently,we identified the key triggers for the reactivation of ancient landslides,including water infiltration,reservoir hydrodynamics,slope erosion,and excavation,by analyzing representative cases in the study area.Reactivation of ancient landslides is sometimes the result of the cumulative effects of multiple predisposing factors.Furthermore,our investigations revealed that the reactivation of these ancient landslides primarily led to local failures.However,over extended periods of dynamic action,the entire zone may experience gradual creep.We categorized the reactivation modes of ancient landslides into three distinct types based on the reactivation sequences:progressive retreat,backward thrusting,and forward pulling–backward thrusting.This study is of great significance for us to identify ancient landslides,deepen our understanding of the failure modes and risks of reactivated ancient landslides on the eastern margin of the Tibetan Plateau,and formulate effective disaster prevention and mitigation measures.

A Study on German Translation Strategies of Culture-Loaded Words in Documentary Hexi Corridor(Expert)by Adaptation Theory

This paper deals with the translation strategies of Chinese Culture-Loaded Words from the perspective of adaptation theory.It is based on the translation text of the sixth episode“Silk Road”and the seventh episode“Dunhuang”of the documentary Hexi Corridor.Many words with Chinese cultural connotations appear in the subtitles of this documentary.This paper will be divided into four parts.The first part and the second part deal with the basic theories,i.e.,definition of Chinese Culture-Loaded Words and of adaptation theory.The original text is analysed in the third part.This part deals with the background and specifics of the language of the documentary film Hexi Corridor.The fourth part deals with the difficulties encountered by the author in translation practice and the corresponding solutions adopted by the author.The translation difficulties are solved by five translation methods,namely transliteration,loan translation,substitution,interpretation,and adaptation.

关于打通铁路网运输能力堵点对策探究

国铁企业落实党中央部署要求并加快推进铁路货运市场化改革,采取有效措施尽快打通铁路网运输能力堵点,有效降低物流成本。通过分析路网总体规模、旅客运输供给能力、货物运输保障能力等铁路网运输能力现状,剖析铁路网运输能力堵点及成因。在此基础上,提出加强铁路网运输能力经验借鉴,探析打通铁路网运输能力堵点对策,即:畅通普速干线通道,加强煤运通道能力保障,强化中欧班列通道能力,完善港口铁路通过能力,增强西部陆海新通道线路能力,完善枢纽点线配套能力,强化铁路货运设施设备卸车能力等方面,在助力降低全社会物流成本中发挥“火车头”的重要作用。

基于功能连接度的城市生态廊道空间范围划定研究

如何科学确定城市生态廊道空间范围是城乡规划和风景园林领域最为关心的问题之一。基于电路理论模型量化源地间物种转移廊道的功能连接度,引入经济学“效益成本比”思想构建城市生态廊道空间范围划定模型,提取生态廊道功能连接度效益成本比的拐点作为该条廊道规划建设的参照宽度。结果显示:(1)研究区共识别59个30hm^(2)以上的生态源地,其中大型生态源地多处在研究区外围,景观阻力面空间分布特征具有明显地“核心-边缘”特征;(2)基于最小成本路径模型与电路理论提取出126条生态廊道,并识别了重要生态源地、夹点及障碍点,发现障碍点与夹点空间存在明显拮抗关系;(3)整合电路理论(Circuitscape平台Pairwise模式)与分段线性回归模型划定研究区城市生态廊道的参考宽度范围处于60.27~371.83m,并对比了现有功能连接度量化方法对廊道参照宽度有潜在影响。以上研究结论可为今后城市乃至区域生态网络构建提供科学借鉴。

甘肃五坝墓地人骨反映的史前人群变迁

在跨大陆交流的大背景下,河西走廊史前时期人群的迁徙、扩散、融合及其与古文化发展之间的关系等问题一直备受关注。但人骨材料的缺乏使学界对该区新石器时代人群的来源及其与青铜时代人群的关系并不清楚。本文以地处河西走廊中部的五坝墓地(4400~3800 BP)中出土的14例成年个体颅骨为研究对象,进行了非测量和测量性状的分析。结果显示:五坝人群属东亚类群,与青海省东北部新石器时代晚期人群具有最近的亲缘关系。对河西地区史前时期人群变迁历史的梳理则表明该地区至少经历了两次大规模的人群迁徙:新石器时代晚期,来自河湟地区的农人成规模地向河西走廊扩散,同时带来了波浪式的文化传播;青铜时代早中期,该区人群的颅面部形态特征变得相对复杂,但人群属性并未发生根本性变化。青铜时代晚期以后,欧亚草原游牧人群的大规模南下使河西人群的颅面部形态发生明显改变,也使该地区迎来了考古学文化和生业方式的转型。

不同结构因子下带连廊高层建筑外墙火竖向蔓延数值模拟

目的 研究带连廊高层建筑发生火灾时火焰蔓延的变化规律,为该类建筑的防火设计提供参考。方法 应用火灾数值模拟软件FDS建立一个33层带连廊建筑模型,分别改变结构因子、窗口数量两种因素进行模拟,分析该模型在不同条件下的温度分布等温线和温度曲线。结果 结构因子为0.4、0.8、1.2,窗口数量为二、三、四时,达到危险温度540℃,火焰融合高度随结构因子和窗口数量增加而上升;随着结构因子的增加,火焰融合高度提高了0.25~12.5 m;随着窗口数量的增加,火焰融合高度上升了0.9~6.37 m;结论 带连廊高层建筑外墙火焰蔓延高度受结构因子和窗口数量影响;随着窗口数量增加,结构因子对火焰融合高度影响越大,结构因子越大,火焰融合高度越高;建议带连廊高层建筑连廊部分结构因子小于0.8,并选用结构因子为0.8时的火焰融合高度作为外部蔓延防火阻隔区高度。

东北地区湿地水鸟生态廊道的识别研究

生态廊道作为应对气候变化的生物多样性保护模式,目前已成为国际生态领域研究的热点之一。但是有关水鸟的生态廊道研究相对很少。以构建湿地水鸟的生态廊道为研究目的,东北地区为研究区,丹顶鹤、灰鹤、大天鹅和中华秋沙鸭四种湿地水鸟为研究对象,采用最小阻力模型和电流理论相结合的混合模型方法,构建四种湿地水鸟的生态廊道。基于最小阻力模型的水鸟生态廊道结果表明:四种水鸟生态廊道的最低成本路线都是将各邻近核心生境斑块连接起来的路线,但是它们的数量、分布和最大宽度有所不同。基于电流理论的水鸟生态廊道结果表明:四种水鸟生态廊道的电流密度、夹点区域数目有所不同。研究采用四种水鸟的实际观测数据来进行生态廊道模拟结果验证。验证结果发现:大部分的水鸟出现点距水鸟最低成本路线不远,说明部分基于最小阻力模型生成的最低成本路线是最有可能成为水鸟生态廊道的地方。大部分的水鸟出现点与水鸟的夹点区域重合,说明基于电流理论生成的夹点区域是最有可能成为水鸟生态廊道的地方。研究采用的方法和结果是对区域尺度水鸟生态廊道构建的一种尝试,对其他国家区域尺度上的多物种水鸟生态廊道的构建具有一定的借鉴和参考价值。

基于“源地-阻力-廊道”的三江源区生态安全格局构建

三江源区是青藏高原生态屏障的重要组成部分,科学构建生态安全格局对筑牢三江源区生态安全屏障、维护可持续发展具有重要意义。耦合层次分析法(AHP)与熵权法,基于生态系统服务、形态学空间格局分析(MSPA)、景观连通性等方法识别不同等级生态源地,利用土地利用类型并综合生态敏感性与地形位指数构建生态阻力面,基于Linkage Mapper工具识别不同类别生态廊道,构建三江源区生态安全格局。结果表明:(1)三江源区生态源地约52371.30km2,占研究区总面积13.70%,多为大尺度不规则斑块,呈现东多西少的空间分布格局;其中一级生态源地面积约为48290.06km2,占生态源地总面积的92.21%,集中分布在生态系统服务重要性较高的中部与东南部地区。(2)识别生态廊道共328条,廊道分布呈现中东部密集,西部稀疏的蜘蛛网状空间格局,整体呈东西向波状延伸态势。(3)识别生态夹点1796km2、生态障碍点2490km2,主要分布于研究区中南部的杂多县;提取生态断裂点61处,集中分布于治多县东南部。(4)构建“三区三带多点”生态安全格局,以生态维育发展区、中部修复关键区、西部生态保护区为“三区”,以绿水青山维护带、生物保护关键带、河源安全建设带为“三带”,识别核心修复点为“多点”,考虑不同小区域内的生态状况,因地制宜进行生态建设。研究结果可以为三江源区生态保护地优化提供科学建议。

创新型城区体育运动空间布局规划策略——以杭州城西科创大走廊为例

梳理我国体育运动空间的发展演变历程及其规划布局的理论方法,分析创新型城区体育运动空间布局规划的难点。以健康活力为基本导向,明确“产业—城市—人群”3个方面的发展目标,提出精准匹配、整合联动和运动触媒3大核心策略。同时,以杭州城西科创大走廊的体育运动空间布局实践为例,对3大核心策略加以验证,以期为我国其他创新型城区的健康活力发展提供参考。

民族走廊学说与区域舞蹈文化研究——以南岭民族走廊为例

本文以费孝通先生提出的民族走廊学说为研究视角,以南岭民族走廊为研究对象,对走廊所包含的东段粤北地区、中段桂东北地区、北段湘西南地区的瑶族、汉族、壮族、苗族、侗族、客家等族群舞蹈的分布及互动展开比较研究。拟从区域舞蹈文化研究的范式转变、民族迁徙、信仰流播、“中心”与“边缘”等多元视角来看族群舞蹈文化的互动互融,印证南岭民族走廊各族群在历史上的动态流变,以此阐释中华民族多元一体理论的形成与发展,为南岭民族走廊舞蹈文化研究提供更多研究的视角与案例。