Local level rainfall and temperature variability in drought-prone districts of rural Sidama,central rift valley region of Ethiopia

ABSTRACT

The purpose of this study is to examine local level spatiotemporal rainfall and temperature variability in drought-prone districts of rural Sidama, Central Rift Valley region of Ethiopia. The study used 129 gridded monthly rainfall and temperature data of 32 years (1983–2014). The gridded rainfall and temperature records were encoded into GIS software and evaluated through different statistical and geospatial techniques. Mann-Kendal rank test and F distribution tests were used to test temporal and spatial statistical significance, respectively, of the data. The analysis revealed that Belg and Kiremt are the main rainfall seasons, constituting 81% of the annual rainfall. Although annual, Kiremt, and Belg rainfall amounts appear to have decreased over time, the decreasing trend is statistically significant only for Belg rainfall records. On the other hand, rainfall standard anomaly results indicated seven droughts of different magnitudes: one extreme, two severe, and four moderate. The study also revealed increasing temperature trends over the years under consideration that are statistically significant. The findings of this study on rainfall contradict other findings obtained around the study area. Thus, climate change adaptations need to focus on location-specific climate data analysis so that the intended adaptive interventions can be successful.     

Directional interpolation infinite element for dynamic problems in saturated porous media

In this study, a directional interpolation infinite element suited to a saturated porous medium is presented to account for dynamic problems with semi-infi     

长江经济带城市土地利用效率的影响因素及其空间溢出效应研究

在人多地少的基本国情下,提高城市土地利用效率是促进区域可持续发展和建设生态文明的内在要求。本文在对2009-2016年长江经济带108个地级及以上城市土地利用效率的研究基础上,采用空间相关性研究方法分析了时空分布格局,通过构建空间杜宾模型(SDM)对其空间溢出效应进行分析。研究结果表明:1)2009-2016年长江经济带城市土地利用效率整体呈现稳定上升趋势;基本呈现以上海、南京、武汉等不同城市群中心城市向外逐步降低的“中心-外围”的分布格局。2)通过构建空间杜宾模型分析发现,经济发展水平、产业结构有显著为正的直接效应和溢出效应;土地市场化水平有显著为正的溢出效应;城市固定资产投资对城市土地利用效率具有正的直接效应和负的溢出效应;政府财政支出水平则对城市土地利用效率的直接效应和溢出效应均不明显。3)不同影响因素对经济带上中下游城市土地利用效率的空间效应存在一定差异性。     

PTP协议在广电时间同步网中的应用研究

随着广电行业的飞速发展,以串行数字接口(SDI)基带信号为基础技术架构的传统电视信号已经很难满足未来技术发展和业务扩展的需求．得益于现代通信技术的迅速发展以及即将到来的万物互联的5G时代,广电行业也将采用IP化技术来构建新的网络系统．处在向IP化发展的过渡期,广电IP化目前还存在一些亟待解决的问题．为了解决广电系统网络中需要更高精度的同步信号来完成时间同步的问题,本文利用精确时间协议（PTP）时间同步技术在专用以太网中完成时间同步组网,搭建了测试环境并对测试数据进行了分析．测试结果表明,相较于传统的网络时间协议（NTP）时间同步技术,输出PTP信号的准确度能够达到亚微秒量级,完全满足广电行业IP化数字电视系统时间同步信号的高精度需求．      

A natural language processing and geospatial clustering framework for harvesting local place names from geotagged housing advertisements

Local place names are frequently used by residents living in a geographic region. Such place names may not be recorded in existing gazetteers, due to their vernacular nature, relative insignificance to a gazetteer covering a large area (e.g. the entire world), recent establishment (e.g. the name of a newly-opened shopping center) or other reasons. While not always recorded, local place names play important roles in many applications, from supporting public participation in urban planning to locating victims in disaster response. In this paper, we propose a computational framework for harvesting local place names from geotagged housing advertisements. We make use of those advertisements posted on local-oriented websites, such as Craigslist, where local place names are often mentioned. The proposed framework consists of two stages: natural language processing (NLP) and geospatial clustering. The NLP stage examines the textual content of housing advertisements and extracts place name candidates. The geospatial stage focuses on the coordinates associated with the extracted place name candidates and performs multiscale geospatial clustering to filter out the non-place names. We evaluate our framework by comparing its performance with those of six baselines. We also compare our result with four existing gazetteers to demonstrate the not-yet-recorded local place names discovered by our framework.     

Swedish Forests in the Bioeconomy: Stories from the National Forest Program

Abstract

The concept of a bioeconomy has been placed central in formation of a Swedish National Forest Program (NFP). Drawing on Hajer’s conceptual framework of storylines, we present a discourse analysis of the working group reports underlying the establishment of the NFP strategy. We ask what stories about Swedish forests come to dominate the NFP process, how well they reflect the commitment of balancing economic, social and environmental interests, and what role the concept of a bioeconomy, has on the formation of these stories. Storylines of Swedish forests in the bioeconomy unite wider European discourses on the bioeconomy and climate change with historical Swedish forest policy discourses, revitalizing a discourse coalition comprising the state and the industry. Particular to the Swedish discourse is the strong emphasis on creating consensus around a single story of the forest-based bioeconomy.     

Phase Shift between Changes in Global Temperature and Atmospheric CO2 Content under External Emissions of Greenhouse Gases into the Atmosphere

Izvestiya, Atmospheric and Oceanic Physics - The phase shift between changes in the global surface temperature Tg and atmospheric CO2 content $${{q}_{{{\text{C}}{{{\text{O}}}_{2}}}}}$$ has been...     

一种潜艇装备作战能力比较研究方法

对潜艇装备作战能力评估问题进行了研究，发现运用定量评估方法的过程中存在指标评价所需数据无法完全获取的问题。结合美弗吉尼亚潜艇改进情况，分析了影响潜艇作战能力的一些关键因素，重点基于潜艇武器装载能力，对国外典型潜艇进行了作战能力比较分析，最后对分析结果进行了评价，并讨论了未来潜艇作战能力评估方法的发展方向。     

Discovery of Four New Clusters in the Cygnus Cloud

We report the discovery of four new open clusters(named QC 1,QC 2,QC 3 and QC 4)in the direction of Cygnus Cloud and select their members based on five astrometric parameters(l,b,ω,μα*,μδ)of Gaia DR2.We also derive their astrophysical parameters for each new cluster.Structure parameters are generated by fitting the radial density distribution with a King’s profile.Using solar metallicity,we performed isochrone-fitting on their purified color-magnitude diagrams(CMDs)to derive the age of the clusters.The known cluster NGC 7062 in an adjacent area is chosen to verify our identification process.The estimated distance,reddening and age of NGC 7062 are in good agreement with the literature.     

Evaluating soil water routing approaches in watershed-scale,ecohydrologic modelling

Soil water dynamics are central in linking and regulating natural cycles in ecohydrology, however, mathematical representation of soil water processes in models is challenging given the complexity of these interactions. To assess the impacts of soil water simulation approaches on various model outputs, the Soil and Water Assessment Tool was modified to accommodate an alternative soil water percolation method and tested at two geographically and climatically distinct, instrumented watersheds in the United States. Soil water was evaluated at the site scale via measured observations, and hydrologic and biophysical outputs were analysed at the watershed scale. Results demonstrated an improved Kling–Gupta Efficiency of up to 0.3 and a reduction in percent bias from 5 to 25% at the site scale, when soil water percolation was changed from a threshold, bucket-based approach to an alternative approach based on variable hydraulic conductivity. The primary difference between the approaches was attributed to the ability to simulate soil water content above field capacity for successive days; however, regardless of the approach, a lack of site-specific characterization of soil properties by the soils database at the site scale was found to severely limit the analysis. Differences in approach led to a regime shift in percolation from a few, high magnitude events to frequent, low magnitude events. At the watershed scale, the variable hydraulic conductivity-based approach reduced average annual percolation by 20–50 mm, directly impacting the water balance and subsequently biophysical predictions. For instance, annual denitrification increased by 14–24 kg/ha for the new approach. Overall, the study demonstrates the need for continued efforts to enhance soil water model representation for improving biophysical process simulations.