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SDI planning using the system dynamics technique within a community of practice:lessons learnt from Tanzania

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Geo-Spatial Information Science 2015年第2期18卷 97-110页

作者： Ali MANSOURIAN Alex LUBIDA Petter PILESJÖ Ehsan ABDOLMAJIDI Monica LASSI GIS Center Department of Physical Geography and Ecosystem ScienceLund UniversitySölvegatan 1222362 LundSweden department of Research and Study Services Lund University LibraryLund UniversityHelgonabacken 1Box 3SE-22100 LundSweden

There exist major challenges in accelerating the spatial data infrastructure(SDI)planning process in the developing countries as well as advocating for politicians to support the development of SDI,due to the high complexity of SDI,lack of knowledge and experience,and limited insight in the *** address these challenges,a methodology for SDI planning in Tanzania,based on the system dynamics technique and the communities of practice concept,was adopted and applied within a community consisting of experts from stakeholder *** groups gathered to develop an SDI plan,while they shared their knowledge and discussed their ideas that helped their understanding of *** running the system dynamics model,the development of SDI over time could be simulated that gave the planning community an insight about the future effects of today’s plans and ***,an optimum model could be developed by refinements and improvements done with the consensus of the SDI *** model included the components and policies that are essential for a successful SDI implementation in Tanzania and can be used as a basis for SDI planning and help to gain political *** learnt from this research were promising regarding the usability of the methodology for SDI planning in comparable countries.

关键词： spatial data infrastructure(SDI) planning system dynamics technique community of practice

Origin of the spatial consistency of summer precipitation variability between the Mongolian Plateau and the mid-latitude East Asian summer monsoon region

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Science China Earth Sciences 2020年第8期63卷 1199-1208页

作者： Jie CHEN Wei HUANG Qiong ZHANG Song FENG Key Laboratory of Western China s Environmental Systems(Ministry of Education) College of Earth and Environmental SciencesLanzhou UniversityLanzhou 730000China department of physical geography and Bolin Centre for Climate Research Stockholm UniversityStockholm 10691Sweden department of Geosciences University of ArkansasFayetteville 72701USA

The Mongolian Plateau(MP) is located in the eastern part of arid Central Asia(ACA). Climatically, much of the MP is dominated by the westerly circulation and has an arid and semi-arid climate;however, the eastern part of the MP is also influenced by the East Asian summer monsoon(EASM) and has a humid and semi-humid climate. Several studies have shown that precipitation variability in the MP differs from that in western ACA but is consistent with that in the EASM region. Here we use monthly precipitation data for 1979–2016 to characterize and determine the origin of the summer precipitation variability of the MP and the EASM region. The results show that the MP and the mid-latitude EASM region exhibit a consistent pattern of precipitation variability on interannual and decadal timescales;specifically, the consistent regions are the MP and North and Northeast China. We further investigated the physical mechanisms responsible for the consistent interdecadal precipitation variability between the MP and the mid-latitude EASM region, and found that the mid-latitude wave train over Eurasia, with positive(negative) geopotential height anomalies over the North Atlantic and ACA and negative(positive) geopotential height anomalies over Europe and the MP, is the key factor responsible for the consistency of precipitation variability in the MP and the mid-latitude EASM region. The positive anomalies over the North Atlantic and ACA and negative anomalies over Europe and the MP would enhance the transport of westerly and monsoon moisture to the MP and North and Northeast China. They could also strengthen the Northeast Asian low, enhance the EASM, and trigger the anomalous ascending motion over the MP which promotes precipitation in the MP and in the mid-latitude EASM region. Overall, our results help explain the spatial variations of paleo-precipitation/humidity reconstructions in East Asia and clarify the reasons for the consistency of the regional climate.

关键词： Mongolian Plateau Mid-latitude EASM region Summer precipitation Decadal Consistent variability

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A graph autoencoder network to measure the geometric similarity of drainage networks in scaling transformation

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International Journal of Digital Earth 2023年第1期16卷 1828-1852页

作者： Huafei Yu Tinghua Ai Min Yang Weiming Huang Lars Harrie School of Resource and Environmental Sciences Wuhan UniversityWuhanPeople’s Republic of China department of physical geography and Ecosystem Science Lund UniversityLundSweden School of Computer Science and Engineering Nanyang Technological UniversitySingaporeSingapore

Similarity measurement has been a prevailing research topic geographic information *** similarity measurement inin scaling transformation(GSM_ST)is critical to ensure spatial data quality while balancing detailed information with distinctive ***,GSM_ST is an uncertain problem due to subjective spatial cognition,global and local concerns,and geometric *** rule-based methods considering multiple consistent conditions require subjective adjustments to characteristics and weights,leading to poor robustness in addressing GSM_*** study proposes an unsupervised representation learning framework for automated GSM_ST,using a Graph Autoencoder Network(GAE)and drainage networks as an *** framework involves constructing a drainage graph,designing the GAE architecture for GSM_ST,and using Cosine similarity to measure similarity based on the GAE-derived drainage embeddings in different *** perform extensive experiments and compare methods across 71 drainage networks duringfive scaling *** results show that the proposed GAE method outperforms other methods with a satisfaction ratio of around 88%and has strong ***,our proposed method also can be applied to other scenarios,such as measuring similarity between geographical entities at different times and data from different datasets.

关键词： Geometric similarity measurement drainage network scaling transformation graph autoencoder network

INITIATION AND DEVELOPMENT PROCESSES OF TUNNEL SYSTEMS IN THE HILLY LOESS REGION OF NORTHERN CHINA

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International Journal of Sediment Research 2006年第3期21卷 171-179页

作者： T. X. ZHU1 Dr., department of geography, University of Minnesota-Duluth, 10 University Dr., Duluth, MN 55812, U.S.A. department of geography University of Minnesota-Duluth MN 55812 United States

Tunnel systems in the hilly loess region of northern China are among the largest and most complicated in the world. Tunnel formation and development processes were investigated in the Yangdaogou catchment over the period of 1989 through 2002. Newly formed tunnels on the roads in the Wangjiagou watershed were also examined in detail during a single storm in 2002. Soil samples were taken from various locations of the tunnel systems in the Yangdaogou catchment for chemical and physical analyses. The controlling factors of tunnel formation are surface drainage conditions and soil materials. Rapid downward mechanical erosion by storm flows seems to be responsible for the original formation of inlets. All tunnels are found in loess and none was found in red Tertiary earth. Underground tunnel paths often develop right above an impeding layer, mainly resulting from mechanical erosion rather than chemical dissolution. New inlets develop in old tunnel systems in two major ways. One is roof collapses of an existing tunnel path and the other is the mechanical scouring action of storm flows. A tunnel system can expand upslope or downslope but the associated processes differ. Upslope expansion often starts with the formation of one or more inlets resulting from surface washes, followed by the development of an underground tunnel path. Downslope development of a tunnel system is characterized by uneven enlargement of tunnel paths. This study suggests that the key to control of tunnel development is reducing surface water entering a tunnel.

关键词： Piping Tunnel erosion Semi-arid areas Gully erosion Loess Plateau

Earthquake vulnerability disaster in the Lembang district of West Bandung Regency, Indonesia

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Earthquake Science 2019年第1期32卷 40-46页

作者： Fahmi Arif Kurnianto Fahrudi Ahwan Ikhsan Bejo Apriyanto Elan Artono Nurdin department of geography Education University of Jember

This research is concerned with an analysis of the level of vulnerability for an earthquake disaster in Lembang district,an area in West Java that includes the Bandung basin and has a high potential for earthquake *** Lembang district is close to the active Lembang fault whose movement can cause earthquakes of magnitude 7 on the Richter scale(Tempo Interaktif,May 11,2010).The research method used to assess the level of vulnerability is essentially a descriptive *** data analysis is based on calculating an earthquake disaster risk index(EDRI),which is in turn based on assessment of the region's social,physical and economic *** vulnerability level for earthquake disaster in the Lembang is ranked as medium *** social vulnerability of the population is the major contributing factor given the high population density and growth rate for the *** physical characteristics of the district,which includes mild temperatures and attractive scenery,make many people want to stay in and visit *** construction quality of buildings is so bad that they are not designed to withstand earthquakes,so improvement of building infrastructure is an alternative to reducing the various physical vulnerabilities.

关键词： vulnerability earthquake mitigation west Bandung Indonesia

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Validation of AOGCMs Capabilities for Simulation Length of Dry Spells under the Climate Change in Southwestern Area of Iran

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Open Journal of Air Pollution 2015年第2期4卷 76-85页

作者： Sayed Keramat Hashemi-Ana Mahmood Khosravi Taghi Tavousi department of physical geography and Climatology University of Sistan and Baluchestan Zahedan Iran

Identification and extraction length of dry spells in arid and semi-arid regions is very important. Thus, the use of climate change prediction models for study the behavior of the climatic parameters in the future time is inevitable. With recognition of the spatial and temporal behavior variables such as precipitation, we can prevent from destructive effects. In this research, the performance of Atmosphere-Ocean General Circulation Models (AOGCMs) was evaluated for simulation length of dry spells in the south-western area of Iran. The results show that the length of dry spell is relatively decreased in cold seasons (autumn and winter) and increased in the warm season (spring and summer) in both A2 and B2 Scenarios. The length of the dry spell on monthly scale for scenario A2 is 6% (equivalent to 2 days) and for scenario B2 is 9 percent (approximately 2.4 day) increased compared to the baseline period. For assess the uncertainty, AOGCMs were weighting. The results show that the best model for simulation of dry spells is HADCM3 and GFCM2.1, because the results have a less error. On the other hand, NCCCSM have the lowest weight for simulation dry spells in both scenarios.

关键词： Climate Change AOGCMs Dry Spells Scenarios Southwest Iran Simulation

Seismic vulnerability assessment of urban buildings using the rough set theory and weighted linear combination

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Journal of Mountain Science 2022年第3期19卷 849-861页

作者： Yasaman ASADI Najmeh NEYSANI SAMANY Majid KIAVARZ MOQADAM Ata ABDOLLAHI KAKROODI Meysam ARGANY department of Remote Sensing and GIS Faculty of GeographyUniversity TehranTehran 33137-67464Iran

Seismic vulnerability assessment of urban buildings is among the most crucial procedures to post-disaster response and recovery of infrastructure *** present study proceeds to estimate the seismic vulnerability of urban buildings and proposes a new framework training on the two ***,a comprehensive interpretation of the effective parameters of this phenomenon including physical and human factors is ***,the Rough Set theory is used to reduce the integration uncertainties,as there are numerous quantitative and qualitative *** objectives were conducted on seven distinct earthquake scenarios with different intensities based on distance from the fault line and the *** proposed method was implemented by measuring seismic vulnerability for the seven specified seismic *** final results indicated that among the entire studied buildings,71.5%were highly vulnerable as concerning the highest earthquake scenario(intensity=7 MM and acceleration calculated based on the epicenter),while in the lowest earthquake scenario(intensity=5 MM),the percentage of vulnerable buildings decreased to approximately 57%.Also,the findings proved that the distance from the fault line rather than the earthquake center(epicenter)has a significant effect on the seismic vulnerability of urban *** model was evaluated by comparing the results with the weighted linear combination(WLC)*** accuracy of the proposed model was substantiated according to evaluation *** assessment based on the distance from the epicenter and its comparison with the distance from the fault shows significant reliable results.

关键词： Seismic vulnerability Urban buildings Rough set theory Earthquake scenarios WLC

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Applying a support vector model to assess land cover changes in the Uvs Lake Basin ecoregion in Mongolia

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Information Processing in Agriculture 2019年第1期6卷 158-169页

作者： Buyan-Erdene Jamsran Chinsu Lin Ishgaldan Byambakhuu Jamsran Raash Khaulenbek Akhmadi department of Forestry and Natural Resources National Chiayi University300 University Rd.ChiayiChiayi 60004TaiwanChina department of Environment and Forest Engineering School of Engineering and Applied SciencesNational University of MongoliaMongolia Uvs Lake Basin Projected Area Administration Office Uvs ProvinceMongolia Head of Division for Desertification Study Institute of Geography and GeoecologyMongolian Academy of SciencesMongolia

The Uvs Lake Basin in western Mongolia is a natural world heritage site and is known for its diversity in landscape and ***,investigative research has shown that the protected pristine ecotone is suffering land degradation due to global *** order to obtain evidence of the changes over a long-term time scale,serial multi-temporal Landsat images obtained between 1995 and 2015 were used to classify land cover and land cover changes over the Basin ecoregion using a machine learning classification technique,support vector *** showed that the forest land area in 1995 was 1888.48 km^2 which was equivalent to 7.48%of the total area of the study *** forest area showed considerable decrease by 301.36 km^2 during the first decade(1995–2004)and 155.81 km^2 during second decade(2004–2015).A total of 457.17 km^2 or 24.21%of the forest land has been developed,most being changed into *** major driver of such changes was illegal logging,forest fire,and pest *** grassland was changed primarily into bare land during the two *** area of glacier was decreased and primarily changed into water *** contrast,the area of sand in the Basin ecoregion increased dramatically from 65.20 km^2 in 1995 to 318.33 km^2 in 2015 the increase being mostly from the transition of bare *** summary,the drivers of the significant decrease of greenness coverage and increase of sand/bare land areas were the interaction of complicated disturbances in both anthropogenic and natural factors,in which logging,grazing,wind erosion,and global warming were the key causes.

关键词： Land suppression Soil degradation Forest reduction Change analysis Landscape ecology

The Distribution of Surface Karst Features in the Bakony Region (Transdanubian Mountains, Hungary)

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Journal of Geological Research 2019年第1期1卷 21-35页

作者： Marton VERESS Szilard VETeSI-FOITH department of geography Eotvos Lóránd UniversitySzombathelyHungary department of physical geography University of PécsPécsHungary

The surface karst of the Bakony Region is described. VES measurements were applied to study the cover and the morphology of the bedrock. A karstmorphological mapping was also performed. A relation was established between the karst types and block types in the mountains. The karstification of the mountains was affected by the block structure of the mountains, the mounds of the uneven bedrock, the presence of superficial deposits and their young denudation. As a result of the above mentioned facts, the karst of the mountains is varied. Soil-covered karst is wide spread in the mountains, but the specific features of this type (solution dolines) only occur on threshold surfaces at the margin of the mountains and on dolomite. The concealed karst was mainly formed on horsts elevated to summit position, but it can also be found on threshold surfaces and on horsts in summit position. Its features are subsidence dolines and depressions of superficial deposit. Cryptokarst and buried karst can be created by gravelly cover or basalt. Where the cover is gravel, epigenetic valleys develop with opened-up phreatic cavities. Where the cover is basalt, ponors develop at its margin, while inside, where the basalt thins out, caprock dolines are formed.

关键词： Block type Karst type Subsidence doline Caprock doline Ponor gorge