Access routes to high mountain huts facing climate-induced environmental changes and adaptive strategies in the Western Alps since the 1990s

ABSTRACT

In the European Alps, high mountain environments are subject to major impacts resulting from climate change, which strongly affect human activities such as mountaineering. The purpose of the study was to examine changes in access routes to 30 high mountain huts in the Western Alps since the 1990s. Data were derived from the use of two different methods, geo-historical studies and a questionnaire, and were used to identify both the climate-related processes affecting the climbing routes and the strategies implemented by public entities, Alpine clubs, guide companies, and hut keepers to maintain acceptable safety and technical conditions. The case studies revealed issues affecting three access routes and the results from the questionnaire showed that the main processes affecting access routes were loss of ice thickness and retreat from the front of the glaciated areas. Commonly, in situ equipment was installed to facilitate access for mountaineers and/or a part of a route was relocated to a safer area. The authors conclude that in most cases, the measures were effective but they were limited by financial, ethical and legal issues, especially in protected or classified areas that could jeopardise their durability and effectiveness.     

塔克拉玛干荒漠-绿洲过渡带尘卷风活动特征——以肖塘为例

利用1992—2011年塔克拉玛干沙漠北缘荒漠-绿洲过渡带肖塘气象站的观测资料,分析了该地区尘卷风的年、月变化规律及其与气象因子的关系。结果表明:(1) 1992—2011年尘卷风发生日数总体呈波动递减趋势;尘卷风主要发生在3—9月,占全年总日数的90.9%,其中4—7月占全年总日数的70%左右。(2)尘卷风月发生日数随月平均地表与1.5 m高处温差的增大而线性增加(r=0.875,P<0.01)。(3)尘卷风月发生日数随着月平均风速的增大而幂函数增加(r=0.89,P<0.01)。(4)尘卷风月发生日数随月平均相对湿度的增大而线性减少(r=-0.869,P<0.01)。     

改进A?的高层建筑逃生路径规划算法研究

针对高层建筑内部结构复杂,发生火灾时没有疏散引导情况,逃生通道极易发生拥堵导致疏散效率降低的问题,本文基于对A*算法的改进,提出了高层建筑逃生路径规划算法。该算法以高层建筑内部路网节点为关键要素,综合火灾发生位置、人员密度、人员数量等因素,从逃生终点优化分配、节点扩展优化、权值优化3个方面进行改进,实现了火灾发生时高层建筑内部的逃生路径规划,并以某高层建筑为例,验证了本文算法的可行性。     

Temporal and Spatial Dynamics Analysis of Grassland Ecosystem Pressure in Kazakhstan

Affected by climate change and policy factors, Kazakhstan is the country with the most severe ecological degradation and grassland conflicts in Central Asia. Therefore, studying the state of grassland carrying resources in Kazakhstan is particularly important for understanding the responses of grassland ecosystems to climate change and human activities. Based on Kazakhstan's remote sensing data and animal husbandry statistics, this study analyzes the patterns of changes in grassland ecosystems in Kazakhstan based on the supply and consumption of these ecosystems. The results show that: 1) From 2003 to 2017, the number of livestock raised in Kazakhstan showed a trend of sustained and steady growth. Due to freezing damage, the scale of livestock farming decreased in 2011, but a spatial difference in the livestock farming structure was not obvious. 2) The fluctuation of grassland supply in Kazakhstan has increased, while the consumption due to animal husbandry has also continued to increase, resulting in an increasing pressure on the grassland carrying capacity. 3) Between 2003 and 2017, the overall grassland carrying status of Kazakhstan have been abundant, but the grassland carrying pressure index has shown a steadily increasing trend, the grassland carrying pressure is growing, and it is mainly determined by grassland productivity. The greater pressure in lower Kyzylorda state, the southern Kazakhstan state of the cultivated land and the northern Kazakhstan state has gradually expanded to include the agro-pastoral zone and the semi-desert zone.     

虚拟地理环境中基于多模式的多人动作捕捉方法

虚拟地理环境对人类理解、探索地理现象以及发现地理现象之间的联系起到很重要的作用。在基于VR技术的虚拟地理环境中更高效,更自然的交互对虚拟地理环境系统的可用性以及理解、探索地理现象的效率至关重要。当前,人机交互中更自然便捷的交互依赖于动作捕捉技术,而现有的基于单种捕捉模式的动作捕捉方式,易受到遮挡、定位漂移等的影响,捕捉精度受到限制,并只能捕捉单个人的动作,不能满足虚拟地理环境对动作捕捉技术提出的特殊需求。针对单种模式的动作捕捉设备应用于虚拟地理环境受到的限制,本文分析了虚拟地理环境系统中的交互需求以及其对动作捕捉技术提出的特殊需求,创新性的提出了一种基于多种动作捕捉模式以捕捉多人动作的方法。本文方法集中于如何融合基于多种模式的多台设备的动作数据,描述了多人动作捕捉框架及其涉及到的技术,在动作捕捉效果上具有明显提升,能够捕捉多人动作,并开发了原型系统对此方法进行了验证。     

北部湾灯光罩网渔场时空分布与海洋环境关系分析 *

文章根据大型灯光罩网渔船调查数据和卫星遥感海面风场(Sea Surface Wind, SSW)、海表温度(Sea Surface Temperature, SST)和叶绿素a浓度(Chlorophyll a concentration, Chl a)资料, 基于广义线性模型(Generalized Linear Model, GLM)对北部湾渔业资源单位捕捞努力量渔获量(Catch Per Unit Effort, CPUE)进行标准化, 应用多元线性回归等方法, 对北部湾灯光罩网渔场的时空分布及其与海洋环境的关系进行了分析。结果表明, 北部湾灯光罩网渔场适宜SST为27~29℃, Chl a为0.5~1.5mg·m ^-3。较高资源量出现在10月份中上旬, 分布在18°—19°N及20°—21°N海域。北部湾灯光罩网渔场的时空分布与季风、19°N附近的暖水池和Chl a等环境因素有关。     

An improved building detection approach using L-band POLSAR two-dimensional time-frequency decomposition over oriented built-up areas

The objective of this study is to efficiently extract detailed information about various man-made targets in oriented built-up areas using polarimetric synthetic aperture radar (POLSAR) images. This paper develops an improved approach for building detection by utilizing Two-Dimensional Time-Frequency (2-D TF) decomposition. This method performs outstandingly in distinguishing between man-made and natural targets based on the isotropic behaviors, frequency-sensitive responses, and scattering mechanisms of objects. The proposed method can preserve the spatial resolution and exploit the advantages of TF decomposition; specifically, the exact outlines of buildings can be effectively located, and more types of features (e.g., flat roofs, roads, and walls that are oblique to the radar illumination) can be distinguished from forests in complex built-up areas by 2-D TF decomposition. The coarser-resolution subaperture images that are produced in the azimuth direction, which correspond to different looking angles, are beneficial for detecting man-made structures with main scattering centers oriented at oblique angles with respect to the radar illumination. In the range direction, the obtained subaperture images, which correspond to various observation frequencies, can be helpful in distinguishing flat roofs and roads from forests. This method was successfully implemented to analyze both NASA/JPL L-band AIRSAR and L-band EMISAR data sets. The building detection results of the proposed method exhibit a significant improvement over those of other methods and reach an overall accuracy over 80%, with approximately 20% higher than the accuracies of K-means clustering and the entropy/alpha-Wishart classifier and approximately 10% higher than the accuracy of the support vector machine method. Moreover, building details can be precisely detected, obliquely oriented buildings can be identified, and the distinction between buildings and forests is significantly improved, as both visually and statistically indicated. This method is highly adaptable and has substantial application value.     

在海洋环境中的酵母菌分布与多样性

最近几年作者对不同海洋环境中的酵母资源、分布和多样性进行的大量研究,从中发现了22属63种1051株。并且发现这些广泛分布在海水、海泥、高盐海水、深海、各种大型海藻表面、各种海鱼体表和体内和红树林生态系统中。不同种的酵母可以产生蛋白酶、脂酶、植酸酶、菊糖酶、纤维素酶、β-1,3-葡聚酶、嗜杀因子、核黄素、铁载体等活性产物,所以这些酵母菌具有广泛的实际用途。     

建筑物沉降观测技术方法探讨

随着城市建设的迅猛发展,城市规模越来越大,建筑物越来越高,由此带来的安全隐患越来越大,由于高层建筑一般采用桩基基础,且荷载较大,对高层建筑的内部基础和设备的位置关系有很高的精度要求,其施工安装阶段将给高层建筑本身及周边建筑群体带来复杂的形变影响。为了保障建筑物施工和运营的安全,就必须对其进行沉降观测。本文结合笔者多年的实际工作经验,并结合具体的实例,对高层建筑物沉降原因、沉降观测前的准备工作及沉降观测的实施过程和观测数据的处理方法等进行了论述,最后指出如何通过沉降观测技术准确地反映出高层建筑物的沉降情况。     

The investigation on particulate organic carbon fluxes with disequilibria between thorium-234 and uranium-238 in the Prydz Bay, the Southern Ocean

Dissolved and particulate thorium-234, particulate organic carbon in the upper 150 m of water columns from five stations in the Prydz Bay, the Southern Ocean were determined during the 22nd Chinese National Antarctic Research Expedition （from November 2005 to March 2006 ）. The disequilibria between thorium-234 and its parent uranium-238 in upper layer was used to derive the averaged residence time of thorium-234, which decreased along with the latitude to the south and a minimum value, 1 - 8 d for particulate thorium-234 and 29 - 48 d for dissolved thorium-234, appeared at the medium latitude station, and the export fluxes of thorium-234 were calculated too and ＇a maximum value, 0. 35 -0. 63 Bq/（m^3 · d） for the particulate thorium-234 and 0. 44 -0. 65 Bq/ （m^3 ·d） for the dissolved thorium-234, appeared at the same station. The export fluxes of particulate organic carbon at different water columns were derived by two methods with irreversible scavenging model, and the averaged values were 104. 7 mmol/ （ m2 · d ） （ E method） and 120. 6 mmol/（ m2·d ） （ B method ）, respectively, indicating that a relatively high new production would exist in summer in the Prydz Bay where it will play a potential significant role in sequestering the absorption CO2 to deeper ocean.