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International Soil and Water Conservation Research 2018年第2期6卷 99-110页

作者： Tung Gia Pham Jan Degener martin kappas Cartography GIS and Remote Sensing DepartmentGottingen UniversityGermany University of Agriculture and Forestry Hue UniversityVietnam

Central Vietnam is very susceptible to soil erosion due to its complicated terrain and heavy rainfall. The objective of this study was to quantify soil erosion in the A Sap river basin, A Luoi district, Thua Thien Hue Province, Vietnam, using the Universal Soil Loss Equation (USLE) and Geographical Informa-tion System (GIS). The results showed that 34% of land area lost accumulated to 10 t ha-1 year-1 while 47% of the total area lost less than 1 t ha-1 year-1. Natural forest land lost the most with an average of about 19 t ha-1 year-1, followed by plantation forest with approximately 7 t ha-1 year-1 and other agricultural lands at 3.70 and 1.45 t ha-1 year-1 for yearly crops and paddy rice, respectively. Soil erosion was most sensitive to the topographic factor (LS), followed by the practice support factor (P), soil erodibility factor (K), cropping management (C), and the rainfall erosivity factor (R). Implications are that changes to the cultivated calendar and implementing intercropping are effective ways to prevent soil erosion in cultivated lands. Furthermore, introducing broad leaves trees for mountainous areas in A Sap basin was the most effective practice in reducing soil erosion. The study also pointed out that the combination of available data sources used with the USLE and GIS technology is a viable option to cal-culate soil erosion in Central Vietnam, which would allow targeted attention toward a solution is to reduce future soil erosion.

关键词： Central Vietnam GIS Soil erosion USLE

Assessment of soil quality indicators under different agricultural land uses and topographic aspects in Central Vietnam

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International Soil and Water Conservation Research 2018年第4期6卷 280-288页

作者： Tung Gia Pham Hung Trong Nguyen martin kappas Cartography GIS and Remote Sensing DepartmentGottingen UniversityGeorge August University of GoettingenGoldschmidstr.537077 GoettingenGermany University of Agriculture and Forestry Hue UniversityVietnam Ministry of Natural Resources and Environment Vietnam

Soil quality assessment is valuable for agricultural production. In this research, 155 soil samples at two soil depths were collected from four land use types in an agricultural area of the A Luoi district in the Central Vietnam. Differences of soil organic carbon, total nitrogen in soil and soil pH under different land use types and topographic aspects were compared. Soil organic carbon contents in arable land and plantation forest are higher than those in natural forest and grassland (p < 0.05). Conversely, the total nitrogen in natural forest was significantly lesser in comparison to other land use types. Meanwhile there were no significant differences of the total nitrogen content (p < 0.05) among arable land, plantation forest, and grassland. The soil of grassland, natural and plantation forests land use types were more significantly acidic than those of the soils of the arable land use type. Soil organic carbon and total nitrogen showed a decreasing trend while soil depth increased in all land use types. The soil pH in plantation forest and arable land use types showed no significant change in relation to soil depth. Significant differences were not found in topographic aspects and soil organic carbon content;however, the different changing trends of soil organic carbon content between land use types and aspects were found. The impact of slope, elevation, farming system or soil texture accounted for the differences in these soil indicators under different land use types in the A Luoi district.

关键词： Central Vietnam Land use type Hilly area Soil quality Topographic aspects

Uncertainty analysis of hydrological modeling in a tropicalarea using different algorithms

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Frontiers of Earth Science 2018年第4期12卷 661-671页

作者： Ammar RAFIEI EMAM martin kappas Steven FASSNACHT Nguyen Hoang Khanh LINH Department of Cartography GIS and Remote SensingUniversity of Goettingen37077GoettingenGermany Colorado State University Fort CollinsCO 80523-1476USA Faculty of Land Resources and Agricultural Environment (FLRAE) Flue University of Agriculture and Forestry (F1UAF)Hue UniversityHue City 0084Vietnam

Hydrological modeling outputs are subject to uncertainty resulting from different sources of errors (e.g., error in input data, model structure, and model parameters), making quantification of uncertainty in hydrological modeling imperative and meant to improve reliability of modeling results. The uncertainty analysis must solve difficulties in calibration of hydrological models, which further increase in areas with data scarcity. The purpose of this study is to apply four uncertainty analysis algorithms to a semi-distributed hydrological model, quantifying different source of uncertainties (especially parameter uncertainty) and evaluate their performance. In this study, the Soil and Water Assessment Tools (SWAT) eco-hydrological model was implemented for the watershed in the center of Vietnam. The sensitivity of parameters was analyzed, and the model was calibrated. The uncertainty analysis for the hydrological model was conducted based on four algorithms: Generalized Likelihood Uncertainty Estimation (GLUE), Sequential Uncertainty Fitting (SUFI), Parameter Solution method (ParaSol) and Particle Swarm Optimization (PSO). The performance of the algorithms was compared using P-factor and Rfactor, coefficient of determination (R2), the Nash Sutcliffe coefficient of efficiency (NSE) and Percent Bias (PBIAS). The results showed the high performance of SUFI and PSO with P-factor>0.83, R-factor 0.91, NSE>0.89, and 0.18<0.32. Hence, we would suggest to use SUFI-2 initially to set the parameter ranges, and further use PSO for final analysis. Indeed, the uncertainty analysis must be accounted when the outcomes of the model use for policy or management decisions.

关键词： SWAT-CUP GLUE SUFI2 ParaSol PSO Vietnam

An integrated methodology for soil moisture analysis using multispectral data in Mongolia

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Geo-Spatial Information Science 2017年第1期20卷 46-55页

作者： Enkhjargal Natsagdorj Tsolmon Renchin martin kappas Batchuluun Tseveen Chimgee Dari Oyunbileg Tsend Ulam-Orgikh Duger NUM-ITC-UNESCO Laboratory for Space Science and Remote Sensing National University of MongoliaUlaanbaatarMongolia Cartography GIS&Remote Sensing DepartmentInstitute of GeographyGeorg-August University GoettingenGoettingenGermany Department of Environment and Forest Engineering National University of MongoliaUlaanbaatarMongolia Department of Statistics National University of MongoliaUlaanbaatarMongolia School of Agroecology Mongolian University of Life SciencesUlaanbaatarMongolia

Soil moisture(SM)content is one of the most important environmental variables in relation to land surface climatology,hydrology,and ***-term SM data-sets on a regional scale provide reasonable information about climate change and global warming specific *** aim of this research work is to develop an integrated methodology for SM of kastanozems soils using multispectral satellite *** study area is Tuv(48°40′30″N and 106°15′55″E)province in the forest steppe zones in *** addition to this,land surface temperature(LST)and normalized difference vegetation index(NDVI)from Landsat satellite images were integrated for the ***,we used a digital elevation model(DEM)from ASTER satellite image with 30-m *** and slope maps were derived from this *** soil moisture index(SMI)was obtained using spectral information from Landsat satellite *** used regression analysis to develop the *** model shows how SMI from satellite depends on LST,NDVI,DEM,Slope,and Aspect in the agricultural *** results of the model were correlated with the ground SM data in Tuv *** results indicate that there is a good agreement between output SM and SM of ground truth for agricultural *** research is focused on moisture mapping for different natural zones in *** innovative part of this research is to estimate SM using drivers which are vegetation,land surface temperature,elevation,aspect,and slope in the forested steppe *** integrative methodology can be applied for different regions with forest and desert steppe zones.

关键词： Remote sensing Landsat soil moisture ground truth measurement modeling

Variability and change of climate extremes from indigenous herder knowledge and at meteorological stations across central Mongolia

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Frontiers of Earth Science 2020年第2期14卷 286-297页

作者： Sukh TUMENJARGAL Steven RFASSNACHT Niah BHVENABLE Alison PKINGSTON Maria EFERNANDEZ-GIMENEZ Batjav BATBUYAN Melinda JLAITURI martin kappas GADYABADAM ESS-Watershed Science Colorado State UniversityFort Collins ColoradoCO 80523-1476USA Cabinet Secretariat of Government of Mongolia State HouseUlaanbaatar City 14201Mongolia Natural Resources Ecology Laboratory Fort Collins ColoradoCO 80523-1499USA Cooperative Institute for Research in the Atmosphere Fort Collins ColoradoCO 80523-1375USA Cartography GIS and Remote Sensing DepartmentInstitute of GeographyGeorg-August Universität GöttingenGöttingen 37007Germany FRS-Rangeland Science Colorado State UniversityFort Collins ColoradoCO 80523-1472USA Center for Nomadic Pastoralism Studies Ulaanbaatar 210620Mongolia Institute of Meteorology Hydrology and the EnvironmentUlaanbaatar 210620Mongolia

In semi-arid regions,air temperatures have increased in the last decades more than in many other parts of the *** has an arid/semi-arid climate and much of the population are herders whose livelihoods depend upon limited water resources that fluctuate with a variable *** were surveyed to identify their observations of changes in climate extremes for two soums of central Mongolia,Ikh-Tamir in the forest steppe north of the Khangai Mountains and Jinst in the desert steppe south of the *** herders’indigenous knowledge of changes in climate extremes mostly aligned with the station-based analyses of *** were warming with more warm days and nights at all *** were fewer cool days and nights observed at the mountain stations both in the summer and winter,yet more cool days and nights were observed in the winter at the desert steppe *** number of summer days is increasing while the number of frost days is decreasing at all *** results of this study support further use of local knowledge and meteorological observations to provide more holistic analysis of climate change in different regions of the world.

关键词： climate change climate extreme indices indigenous knowledge systems temperature precipitation

Comprehensive Euler/Lagrange modelling including particle erosion for confined gas-solid flows

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Particuology 2024年第1期84卷 209-235页

作者： Guiherme A.Novelletto Ricardo martin Sommerfeld Multiphase Flow Systems Institute of Process EngineeringOtto-von-Guericke-University MagdeburgHoher Weg 7b06120Halle(Saale)Germany

The present research aims to assess the capability of a comprehensive Euler/Lagrange approach for predicting gas-solid flows and the associated solid particle *** open-source code OpenFOAM®4.1 was used to carry out the numerical simulations,where the standard Lagrangian libraries were substantially extended to account for all necessary *** are tracked considering both translational and rotational motion as well as all relevant forces,such as gravity/buoyancy,drag and transverse lift due to shear and particle *** tracking time step was dynamically adapted ac-cording to the locally relevant time scales,which drastically reduces computational *** approaches are adopted to model particle turbulent dispersion,particle collisions with rough walls and particle-particle *** solid particle erosion models,available in the literature,were considered to estimate pipe bend *** study cases are provided to validate the adopted nu-merical approach and erosion models *** first case intends to evaluate the ability of the extended CFD code to predict the behaviour of gas-solid flows in pneumatic conveying *** goal is achieved by comparing the numerical results with the experimental data obtained by Huber(1997)and Huber and Sommerfeld(1994,1998)in a pneumatic conveying ***,the importance of considering inter-particle collisions and surface roughness for predicting particle velocity,mass flux and mean diameter distributions in gas-solid flows is *** second and third case intend to evaluate the ability of the erosion models in estimating bend erosion in diluted gas-solid *** erosion data obtained experimentally by Mazumder et al.(2008)and Solnordal et al.(2015)in very dilut pneumatic conveying systems is used for validating the numerical results,neglecting now inter-particle collisions and two-way *** a comprehensive analysis of the different influential properti

关键词： Pneumatic conveying Pipe bend Numerical calculation(CFD) Euler/Lagrange approach Erosion models Wall roughness

Differential roles of seed and sprout regeneration in forest diversity and productivity after disturbance

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Forest Ecosystems 2024年第3期11卷 371-380页

作者： Marek Mejstrík martin Svatek martina Pollastrini martin Sramek Radim Matula Department of Forest Ecology Faculty of Forestry and Wood SciencesCzech University of Life Sciences PragueKamýcka 12916500PragueCzech Republic Department of Forest Botany Dendrology and GeobiocoenologyFaculty of Forestry and Wood TechnologyMendel University in BrnoZemedelska 361300BrnoCzech Republic Department of Agriculture FoodEnvironment and ForestryUniversity of FirenzePiazzale Delle Cascine 2850144FirenzeItaly

Natural regeneration after disturbances is a key phase of forest development,which determines the trajectory of successional changes in tree species composition and *** trees can originate from either seeds or sprouts produced by disturbed trees with sprouting *** both regeneration strategies often develop and co-occur after a disturbance,they tend to affect forest development differently due to significant functional ***,the origin of tree regeneration is rarely distinguished in post-disturbance forest surveys and ecological studies,and the differential roles of seed and sprout regeneration in forest productivity and diversity remain poorly *** address these research gaps,we explored the role of sprout and seed regeneration in the formation of woody species diversity and above-ground biomass(AGB)productivity in early-stage forest *** were collected in two experimental forest stands in the Czech Republic,where trees were cut with varying intensities with the density of residual(uncut)trees ranging from 0 to 275 trees per *** trees were mapped and their sizes were measured before cutting and then,either as a stump with sprouts or a residual tree,remeasured 11 years *** addition,all tree saplings were mapped and measured 11 years after logging,and their origin(sprout or seed)was *** assess abundances and productivity,we estimated AGB of all2,685 sprouting stumps of 19 woody species and 504 generative(i.e.,seed origin)individuals of 16 woody species,using allometric ***-effects models were used to analyze the effects of each regeneration strategy on woody species diversity and the total AGB under varying densities of residual *** multidimensional scaling was used to evaluate the effect of regeneration strategies on species *** and diversity of sprouts were significantly higher than those of seed *** formed on average97.1%of

关键词： Resprouting Seeding Residual trees Tree diversity Above-ground biomass

Applicability limits of the DAX test in plastic bonded explosives

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Defence Technology（防务技术） 2024年第6期36卷 64-70页

作者： martin Künzel Jindrich Kucera Jiri Pachman OZM Research Bliznovice 32Hrochuv Tynec 53862Czech Republic Institute of Energetic Materials Faculty of Chemical TechnologyUniversity of PardubiceStudentska 95Pardubice 53210Czech Republic

The Disc Acceleration e Xperiment(DAX)is one of the most recent experimental methods of performance characterization of new energetic materials.A cylindrical explosive charge accelerates a thin metallic disc and its velocity is measured continuously using photonic Doppler *** detonation velocity is measured *** DAX test can be used to obtain the Chapman-Jouguet(CJ)detonation pressure and to describe detonation products expansion using reduced amount of explosive.A series of DAX tests was performed at various charge diameters and disc thicknesses with Semtex 1 A plastic bonded explosive and sensitized *** DAX-like evaluation was also applied to previously measured data of Semtex 1A and A-IX-1 *** optimum disc thickness is determined by the disc to explosive mass ratio of *** repeatability of the Semtex 1 A detonation pressure results is about four times lower compared to the pressed and liquid explosives.

关键词： Flyer plate Detonation pressure Photonic Doppler velocimetry Semtex

Are TrkB receptor agonists the right tool to fulfill the promises for a therapeutic value of the brain-derived neurotrophic factor?

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Neural Regeneration Research 2024年第1期19卷 29-34页

作者： Marta Zagrebelsky martin Korte Division of Cellular Neurobiology Zoological InstituteTU BraunschweigBraunschweigGermany Helmholtz Centre for Infection Research AG NINDBraunschweigGermany

Brain-derived neurotrophic factor signaling via its receptor tro pomyosin receptor kinase B regulates several crucial physiological *** has been shown to act in the brain,promoting neuronal survival,growth,and plasticity as well as in the rest of the body where it is involved in regulating for instance aspects of the *** to its crucial and very pleiotro pic activity,reduction of brain-derived neurotrophic factor levels and alterations in the brain-derived neurotrophic factor/tropomyosin receptor kinase B signaling have been found to be associated with a wide spectrum of neurological *** r,because of its poor bioavailability and pharmacological properties,brain-derived neurotrophic factor itself has a very low therapeutic ***,the concomitant binding of exogenous brain-derived neurotrophic factor to the p75 neurotrophin receptor has the potential to elicit several unwanted and deleterious side *** re,developing tools and approaches to specifically promote tropomyosin receptor kinase B signaling has become an important goal of translational *** the newly developed tools are different categories of tropomyosin receptor kinase B receptor agonist *** this review,we give a comprehensive description of the diffe rent tro pomyosin receptor kinase B receptor agonist drugs developed so far and of the res ults of their application in animal models of several neurological ***,we discuss the main benefits of tropomyosin receptor kinase B receptor agonists,concentrating especially on the new tropomyosin receptor kinase B agonist *** benefits observed both in vitro and in vivo upon application of tropomyosin receptor kinase B receptor agonist drugs seem to predominantly depend on their general neuroprotective activity and their ability to promote neuronal ***,tro pomyosin receptor kinase B agonist antibodies have been shown to specifically bind the tropomyosin recepto

关键词： Alzheimer's disease brain-derived neurotrophic factor depression Parkinson's disease tropomyosin receptor kinase B receptor

Countermeasures to reduce the risk of infections at the 2024 Olympic and Paralympic Games—A balancing act

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Journal of Sport and Health Science 2024年第6期13卷 722-725页

作者： Marcel Jooste martin Schwellnus Sport Exercise Medicine and Lifestyle Institute(SEMLI)Faculty of Health SciencesUniversity of PretoriaPretoria 0083South Africa Section Sports Medicine Faculty of Health SciencesUniversity of PretoriaPretoria 0083South Africa IOC Research Centre of South Africa Pretoria 0083South Africa

The Olympic and Paralympic Games are a global celebration of athletic dedication and achievement,bringing together athletes and spectators from around the ***,such large gatherings present public health challenges for the Organizing Committees and local *** highlighted by the coronavirus disease 2019(COVID-19)pandemic,these events are associated with an increased risk of transmission of infections,which can significantly impact the health and well-being of athletes and *** the health and safety of athletes,officials and spectators is fundamental to ensure the successful hosting of the ***,it is essential to design and implement comprehensive countermeasures to mitigate the risk of an infectious disease outbreak among participants but also to the residents of the host city.

关键词： gathering bringing infections