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Journal of Geographical Sciences 2017年第1期27卷 79-94页

作者： Asnake MEKURIAW andreas heinimann Gete ZELEKE Hans HURNI Kaspar HURNI Natural Resources Management Department Bahir Dar University Bahir Dar Ethiopia Geospatial Data and Technology Center Bahir Dar University Bahir Dar Ethiopia Center for Development and Environment University of Bern Switzerland Water and Land Resource Center Addis Ababa Ethiopia

An efficient and reliable automated model that can map physical Soil and Water Conservation（SWC） structures on cultivated land was developed using very high spatial resolution imagery obtained from Google Earth and Arc GIS？ERDAS IMAGINE？and SDC Morphology Toolbox for MATLAB and statistical techniques. The model was developed using the following procedures：（1） a high-pass spatial filter algorithm was applied to detect linear features,（2） morphological processing was used to remove unwanted linear features,（3） the raster format was vectorized,（4） the vectorized linear features were split per hectare（ha） and each line was then classified according to its compass directionand（5） the sum of all vector lengths per class of direction per ha was calculated. Finallythe direction class with the greatest length was selected from each ha to predict the physical SWC structures. The model was calibrated and validated on the Ethiopian Highlands. The model correctly mapped 80% of the existing structures. The developed model was then tested at different sites with different topography. The results show that the developed model is feasible for automated mapping of physical SWC structures. Thereforethe model is useful for predicting and mapping physical SWC structures areas across diverse areas.

关键词： physical SWC structure mapping automated mathematical morphology GIS and remote sensing

Remote sensing of land use/cover changes in South and Southeast Asian Countries

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International Journal of Digital Earth 2019年第10期12卷 1099-1102页

作者： Krishna Vadrevu andreas heinimann Garik Gutman Chris Justice NASA Marshall Space Flight Center HuntsvilleAlabama Center for Development and Environment and Institute of Geography University of BernSwitzerland NASA Headquarters WashingtonUSA Department of Geographical Sciences University of Maryland College ParkUSA

Land-Use/Cover Changes(LU/CC)are occurring rapidly in South/Southeast Asian(S/SEA)countries,generally associated with population growth,economic development and competing demands for *** the region,the most common LU/CC changes include urban expansion,agricultural land loss,land abandonment,deforestation,logging,reforestation,agricultural expansion,*** to South Asia,forest cover has been increasing in countries like India,Nepal,and Bhutan due to sustainable afforestation measures;whereas,large-scale deforestation in Southeast Asian countries is continuing,for example,due to oil palm plantation expansion driven by the international market demand in Malaysia and ***-scale deforestation in most of the Southeast Asian countries is due to slash-and-burn agriculture by indigenous people,driven by poverty and population *** activities are common in Myanmar and *** terms of urbanization,South and Southeast Asian countries contain 23 megacities,each with more than 10 million *** in these countries started as urban clusters which grow rapidly,merging into *** urbanization is driving agricultural land loss,and agricultural intensification has been increasing due to less availability of land for growing food crops as,for example,in India,Vietnam,and *** drivers of LU/CC vary widely in the region and include such factors as land tenure,local economic development,government policies,inappropriate land management,land speculation,improved road networks,***,variability in the weather,climate,and socioeconomic factors drive LU/CC resulting in disruptions of biogeochemical cycles,radiation and surface energy balance.

关键词： Southeast crops logging

Factors influencing the adoption of physical soil and water conservation practices in the Ethiopian highlands

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International Soil and Water Conservation Research 2018年第1期6卷 23-30页

作者： Asnake Mekuriaw andreas heinimann Gete Zeleke Hans Hurni Department of Geography and Environmental Studies Addis Ababa UniversityPO Box 1739Bahir DarEthiopia Center for Development and Environment University of BernSwitzerland Water and Land Resource Center Addis AbabaEthiopia

Soil and Water Conservation (SWC) structures have been constructed on cultivated land for nearly 40 years to reduce soil loss and improve crop yields and people's livelihoods in the Ethiopian highlands. However, the success of this huge effort has been mixed, and the main constraints have not been investigated in detail. This study was undertaken to identify the factors determining the adoption of SWC structures in the Ethiopian Highlands. Case study areas were selected from high-potential and low-potential areas. Data were collected from 269 farmers using face-to-face interviews, and through focus group discussions, key informant interviews and field observations. Binary logistic regression model and descriptive statistics were used to analyze the data. The result showed that the majority (87%) of the farmers interviewed were using SWC structures. Regionally, nearly all farmers in the low-potential areas and 56% of farmers in the high-potential areas constructed and were maintaining the structures properly. This disparity is due to the fact that in the low-potential areas there have been strong governmental involvement and technical and financial support, and hence the farmers there have a better understanding of the multiple uses of physical SWC structures than do farmers in the high-potential areas. In addition, off-farm activities and free grazing plays a substantial role. We can conclude that clear understanding of the benefits of SWC structures by farmers, active involvement and technical support from the government, and genuine participation of farmers in SWC practices were found to be main factors in the adoption of SWC measures.

关键词： SWC structures Ethiopian highlands High-potential area Low-potential area Adoption

老挝Phou Khao Khoauy国家公园树木分布特征（英文）

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西部林业科学 2015年第6期44卷 94-99页

作者： Manichanh Satdichanh Jerome Millet andreas heinimann Khamseng Nanthavong Rhett D. Harrison 中国科学院西双版纳热带植物园云南勐腊666303 中国科学院大学北京100049 老挝国立大学林学院老挝 Federation des Conservatoires botaniques nationaux 法国瑞士发展与环境中心瑞士伯尔尼大学地理研究所瑞士世界混农林中心东亚和中亚区域办公室云南昆明650204 中国科学院东亚植物多样性与生物地理重点实验室云南昆明650204

本研究在老挝Phou Khao Khoauy国家公园（在万象东北方向40 km）的两种森林类型取样，以此研究决定树种分布的因素。本研究在海拔为300—450 m地区共设置了11个50 mx50 m样地，并测量了所有胸径大于10cm的树木。调查样地按森林类型（混... 详细信息

本研究在老挝Phou Khao Khoauy国家公园（在万象东北方向40 km）的两种森林类型取样，以此研究决定树种分布的因素。本研究在海拔为300—450 m地区共设置了11个50 mx50 m样地，并测量了所有胸径大于10cm的树木。调查样地按森林类型（混合落叶林，以山毛榉科为主，干常绿林）分层随机选取，共鉴定47个科，70个属，123个种。在每个样地的两个位置收集土壤样品，每个样品在两个深度分别为0～10 cm和10～20 em处采集，并进行基本土壤参数分析（pH值，有机质OM，氮N和磷P，氧化钾K2O，颗粒大小以及质地）。通过聚类分析对植物群落进行标识，使用NMDS分类法及非参数检验法研究土壤对植物分布的影响，揭示了老挝Phou Khao Khoauy国家公园内树种组成与土壤条件的关系。

关键词：植物分布老挝土壤植物群落物种组成热带雨林

Dependence of impact regime boundaries on the initial temperatures of projectiles and targets

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Defence Technology（防务技术） 2024年第1期31卷 49-57页

作者： Stefano Signetti andreas Heine Fraunhofer-Institut für Kurzzeitdynamik Ernst-Mach-InstitutEMIErnst-Zermelo-Str.479104 Freiburg im BreisgauGermany

Towards higher impact velocities,ballistic events are increasingly determined by the material *** effects might range from moderate thermal softening to full phase *** particular,it is of great interest to quantify the conditions for incipient or full melting of metals during impact interactions,which result in a transition from still strength-affected to hydrodynamic material *** this work,we investigate to which extent the respective melting thresholds are also dependent on the initial,and generally elevated,temperatures of projectiles and targets before *** is studied through the application of a model developed recently by the authors to characterize the transition regime between high-velocity and hypervelocity impact,for which the melting thresholds of materials were used as the defining *** obtained results are expected to be of general interest for ballistic application cases where projectiles or targets are *** conditions might result,for example,from aerodynamic forces acting onto a projectile during atmospheric flight,explosive shapedcharge-jet formation or armor exposure to environmental *** performed analyses also broaden the scientific understanding of the relevance of temperature in penetration events,generally known since the 1960s,but often not considered thoroughly in impact studies.

关键词： Ballistic impact Thermal effects Metallic targets Energy partitioning Homologous temperature

REGENERATION FACTOR 1, a peptide boost for wound healing and plant biotechnology

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Molecular Plant 2024年第9期17卷 1333-1334页

作者： andreas Schaller University of Hohenheim Department of Plant Physiology and Biochemistry70593 StuttgartGermany

Plants respond to wounding such as caused by insect herbivores by activating their defenses and thus increasing their resistance against attacking pests and opportunistic pathogens(Howe and Schaller,2008).The phenomenon was first described more than 50 years ago by Green and Ryan,who reported that wounding triggers tomato and potato plants to produce proteinase inhibitors that inhibit digestive proteases in the gut of leaf-eating insects to starve them of nutrients(Green and Ryan,1972).They also observed that the accumulation of proteinase inhibitors is not restricted to wounded leaves but occurs throughout the aerial parts of the *** search for a chemical signal that is released locally in response to wounding and that mediates systemic activation of defense gene expression led to the identification of systemin,the first ever peptide with hormonelike activity in plants(Pearce et al.,1991).These seminal findings sparked much research into systemic defense responses and peptide signaling in general,and we know now that systemin is one of many phytocytokines that regulate a multitude of immune responses in plants(Schilmiller and Howe,2005;Gust et al.,2017).

关键词： wound activation defense

Snapshot imaging of ultrashort electron bunches

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Light(Science & Applications) 2024年第7期13卷 1226-1228页

作者： andreas Döpp Ludwig-Maximilian-Universität München Am Coulombwall 185748GarchingGermany Max Planck Institut für Quantenoptik Hans-Kopfermann-Strasse 1Garching85748Germany

New measurements combine spatial and temporal information from optical transition radiation to estimate the three-dimensional structure of electron bunches from a laser wakefield accelerator.

关键词： ultrashort Snapshot electron

The interaction between a shaped charge jet and a single moving plate

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Defence Technology（防务技术） 2024年第1期31卷 1-13页

作者： andreas Helte Jonas Lundgren Jonas Candle FOI WeaponsProtection and SecuritySE-16490StockholmSweden

Reactive armour is a very efficient add-on armour against shaped charge *** reactive armour consists of one or several plates that are accelerated by an *** but less violent acceleration of plates can also be achieved in a completely inert reactive *** be efficient against elongated jets,the motion of the plates needs to be inclined against the jet such that a sliding contact between the jet and the plates is *** sliding contact causes a deflection and thinning of the *** certain circumstances,the contact will become unstable,leading to severe disturbances on the *** disturbances will drastically reduce the jet penetration performance and it is therefore of interest to study the conditions that leads to an unstable *** studies on the interaction between shaped charge jets and flyer plates have shown that it is mainly the forward moving plate in an explosive reactive armour that is effective in disturbing the *** is usually attributed to the higher plate-to-jet mass flux ratio involved in the collision of the forward moving plate compared to the backward moving *** slow moving plates,as occurs in inert reactive armour,the difference in mass flux for the forward and backward moving plate is much lesser,and it is therefore of interest to study if other factors than the mass flux influences on the protection *** this work,experiments have been performed where a plate is accelerated along its length,interacting with a shaped charge jet that is fired at an oblique angle to the plate’s normal,either against or along the plate’s *** arrangement corresponds to a jet interacting with a flyer plate from a reactive armour,with the exception that the collision velocity is the same for both types of obliquities in these *** experiments show that disturbances on the jet are different in the two cases even though the collision velocities are the *** simulatio

关键词： Reactive armour Flyer plate Shaped charge jet

Note on:“Ballistic model for the prediction of penetration depth and residual velocity in adobe:A new interpretation of the ballistic resistance of earthen masonry”

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Defence Technology（防务技术） 2024年第1期31卷 607-609页

作者： andreas Heine Matthias Wickert Fraunhofer EMI Ernst-Zermelo-Str.479104FreiburgGermany

A recently published modeling approach for the penetration into adobe and previous approaches implicitly criticized are reviewed and *** article contains a note on the paper titled“Ballistic model for the prediction of penetration depth and residual velocity in adobe:A new interpretation of the ballistic resistance of earthen masonry”(DOI:https://***/10.1016/***.2018.07.017).Reply to the Note from Li Piani et al is linked to this article.

关键词： adobe prediction earth

Odd-even effects in the structure and properties of aryl-substituted aliphatic self-assembled monolayers

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Nano Research 2024年第5期17卷 4231-4243页

作者： Piotr Cyganik andreas Terfort Michael Zharnikov Jagiellonian University Faculty of PhysicsAstronomy and Applied Computer ScienceSmoluchowski Institute of PhysicsŁojasiewicza 1130-348 KrakówPoland Institut für Anorganische und Analytische Chemie Universität FrankfurtMax-von-Laue-Straße 760438 FrankfurtGermany Applied Physical Chemistry Heidelberg UniversityIm Neuenheimer Feld 25369120 HeidelbergGermany

Self-assembled monolayers(SAMs)represent an important tool in context of nanofabrication and molecular engineering of surfaces and *** properties of functional SAMs depend not only on the character of the tail groups at the SAM-ambient interface,but are also largely defined by their *** its turn,the latter parameter results from a complex interplay of the structural forces and a variety of other factors,including so called odd-even effects,*** of the SAM structure and properties on the parity of the number(odd or even)of individual building blocks in the backbone of the SAM *** most impressive manifestation of the odd-even effects is the structure of aryl-substituted alkanethiolate SAMs on Au(111)and Ag(111),in which,in spite of the fact that the intermolecular interaction is mostly determined by the aryl part of the monolayers,one observes a pronounced dependence of molecular inclination and,consequently,the packing density of the SAM-forming molecules on the parity of number of methylene units in the alkyl *** we review the properties of the above systems as well as address fundamental reasons behind the odd-even effects,including the existence of a so-called bending potential,which is frequently disregarded in analysis of the structure-building *** generality of the odd-even effects in SAMs is additionally supported by the recent data for SAMs on GaAs,scanning tunneling microscopy data for SAMs on Ag(111),and the data for the monolayers with selenolate and carboxyl anchoring groups on Au(111)and Ag(111).The implications of these effects in terms of the control over the packing density and orientation of the tail groups at the SAM-ambient interface,structural perfection,polymorphism,temperature-driven phase transitions,and SAM stability toward such factors as ionizing radiation,exchange reaction,and electrochemical desorption are *** implications place the odd-even effects as an important tool

关键词： self-assembled monolayers molecular films surface and interface engineering odd-even-effects