Moving Code in Spatial Data Infrastructures – Web Service Based Deployment of Geoprocessing Algorithms     

Matthias Müller  Lars Bernard  Johannes Brauner 《Transactions in GIS》2010,14(Z1):101-118

This article proposes a concept for offering complex geoprocessing functionality in service‐based Spatial Data Infrastructures (SDI). Today, geoprocessing in SDI is typically realized in a data driven manner. Applying the suggested “moving code” approach in a case study in the field of Spatial Decision Support proves its applicability. The proposed solution is analyzed and assessed in terms of gained efficiency, performance behavior and support for distributed development of geoprocessing functionality. In data and computation intensive SDI applications the deployment of moving code proves to be beneficial.  相似文献   

Transformation of amplitudes and frequencies of precession and nutation of the earth’s rotation vector to amplitudes and frequencies of diurnal polar motion     

Burghard Richter  Johannes Engels  Erik Grafarend 《Journal of Geodesy》2010,84(1):1-18

The temporal change of the rotation vector of a rotating body is, in the first order, identical in a space-fixed system and in a body-fixed system. Therefore, if the motion of the rotation axis of the earth relative to a space-fixed system is given as a function of time, it should be possible to compute its motion relative to an earth-fixed system, and vice versa. This paper presents such a transformation. Two models of motion of the rotation axis in the space-fixed system are considered: one consisting only of a regular (i.e., strictly conical) precession and one extended by circular nutation components, which are superimposed upon the regular precession. The Euler angles describing the orientation of the earth-fixed system with respect to the space-fixed system are derived by an analytical solution of the kinematical Eulerian differential equations. In the first case (precession only), this is directly possible, and in the second case (precession and nutation), a solution is achieved by a perturbation approach, where the result of the first case serves as an approximation and nutation is regarded as a small perturbation, which is treated in a linearized form. The transformation by means of these Euler angles shows that the rotation axis performs in the earth-fixed system retrograde conical revolutions with small amplitudes, namely one revolution with a period of one sidereal day corresponding to precession and one revolution with a period which is slightly smaller or larger than one sidereal day corresponding to each (prograde or retrograde) circular nutation component. The peculiar feature of the derivation presented here is the analytical solution of the Eulerian differential equations.  相似文献   

State‐Led Innovation at the City Level: Policy Measures to Promote New Energy Vehicles in Shenzhen,China     

Johannes Lauer  Ingo Liefner 《Geographical review》2019,109(3):436-456

Unlike many Western countries, the Chinese state has a much more active role in innovation that includes direct involvement with actors in innovation processes and the use of state capacity, money, and power to attain certain goals. With the rise of China, innovation processes that critically depend on state action, often labeled state‐led innovation, have thus received growing scholarly attention. However, only few contributions study the specific sector of new energy vehicles (NEV) and policy measures applied at the city level. This paper examines policy and planning tools used in Shenzhen, China, to assert innovation in the NEV industry, using an evaluation of documents and interviews. The paper finds that a city can play a decisive role in the implementation of innovation policy, and Chinese cities in particular make use of a broad set of innovation support measures ranging from binding quotas, public procurement, and incentives to bans and orders. The findings underline the importance of strong regulatory instruments that do not conform to the Western notion of market‐compliant policy, but nevertheless work effectively in the Chinese context. Moreover, the results highlight how successful policy support for innovation in the NEV can be implemented.  相似文献   

Hydrological modelling in the anthroposphere: predicting local runoff in a heavily modified high-alpine catchment     

Johannes Wesemann  Mathew Herrnegger  Karsten Schulz 《山地科学学报》2018,15(5):921-938

Hydrological models within inflow forecasting systems for high-alpine hydropower reservoirs can provide valuable information as part of a decision support system for the improvement of hydropower production or flood retention. The information, especially concerning runoff, is however rarely available for the calibration of the hydrological models used. Therefore, a method is presented to derive local runoff from secondary information for the calibration of the model parameters of the rainfallrunoff model COSERO. Changes in water levels in reservoirs, reservoir outflows, discharge measurements at water intakes and in transport lines are thereby used to derive the local, “natural” flow for a given sub-catchment. The proposed method is applied within a research study for the ÖBB Infrastructure Railsystem division in the Stubache catchment in the central Austrian Alps. Here, the ÖBB operates the hydropower scheme “Kraftwerksgruppe Stubachtal”, which consists of 7 reservoirs and 4 hydropower stations. The hydrological model has been set up considering this human influences and the high natural heterogeneity in topography and land cover, including glaciers. Overall, the hydrological model performs mostly well for the catchment with highest NSE values of 0.78 for the calibration and 0.79 for the validation period, also considering the use of homogeneous parameter fields and the uncertainty of the derived local discharge values. The derived runoff data proved to be useful information for the model calibration. Further analysis, examining the water balance and its components as well as snow cover, showed satisfactory simulation results. In conclusion, a unique runoff dataset for a small scale high-alpine catchment has been created to establish a hydrological flow prediction model which in a further step can be used for improved and sustainable hydropower management.  相似文献   

Structure and Dynamical Influence of Water Vapor in the Lower Tropical Troposphere     

Bjorn Stevens  Hélène Brogniez  Christoph Kiemle  Jean-Lionel Lacour  Cyril Crevoisier  Johannes Kiliani 《Surveys in Geophysics》2017,38(6):1371-1397

In situ, airborne and satellite measurements are used to characterize the structure of water vapor in the lower tropical troposphere—below the height, \(z_*,\) of the triple-point isotherm, \(T_*.\) The measurements are evaluated in light of understanding of how lower-tropospheric water vapor influences clouds, convection and circulation, through both radiative and thermodynamic effects. Lower-tropospheric water vapor, which concentrates in the first few kilometers above the boundary layer, controls the radiative cooling profile of the boundary layer and lower troposphere. Elevated moist layers originating from a preferred level of convective detrainment induce a profile of radiative cooling that drives circulations which reinforce such features. A theory for this preferred level of cumulus termination is advanced, whereby the difference between \(T_*\) and the temperature at which primary ice forms gives a ‘first-mover advantage’ to glaciating cumulus convection, thereby concentrating the regions of the deepest convection and leading to more clouds and moisture near the triple point. A preferred level of convective detrainment near \(T_*\) implies relative humidity reversals below \(z*\) which are difficult to identify using retrievals from satellite-borne microwave and infrared sounders. Isotopologues retrievals provide a hint of such features and their ability to constrain the structure of the vertical humidity profile merits further study. Nonetheless, it will likely remain challenging to resolve dynamically important aspects of the vertical structure of water vapor from space using only passive sensors.  相似文献   

Velocity profiles and basal stresses in natural debris flows     

Georg Nagl  Johannes Hübl  Roland Kaitna 《地球表面变化过程与地形》2020,45(8):1764-1776

The internal deformation within debris flows holds essential information on dynamics and flow resistance of such mass-wasting processes. Systematic measurements of velocity profiles in real-scale debris flows are not yet available. Additionally, data on basal stresses of the solid and the fluid phase are rare. Here, we present and analyse measurements of vertical velocity profiles in two debris flows naturally occurring in the Gadria Creek, Italy. The method is based on cross-correlation of paired conductivity signals from an array of sensors installed on a fin-shaped wall located in the middle of the channel. Additionally, we measure normal stress and pore fluid pressure by two force plates with integrated pressure transducers. We find internal deformation throughout the flows. Only at the very front was some en-bloc movement observed. Velocity profiles varied from front to tail and between flows. For one debris flow, pore fluid pressure close to normal stress was measured, whereas the other flow was less liquefied. The median shear rates were mostly less than 5 s⁻¹ and Savage numbers at the basal layer ranged from 0.01 to 1. Our results highlight the variable nature of debris flows and provide quantitative data on shear rate and basal stress distribution to help guide model development for hazard assessment and landscape evolution. © 2020 The Authors. Earth Surface Processes and Landforms published by John Wiley & Sons Ltd.  相似文献   

A comparison of baseline methodologies for 'Reducing Emissions from Deforestation and Degradation'     

Michael Huettner  Rik Leemans  Kasper Kok  Johannes Ebeling 《Carbon balance and management》2009,4(1):4-12

Background  

A mechanism for emission reductions from deforestation and degradation (REDD) is very likely to be included in a future climate agreement. The choice of REDD baseline methodologies will crucially influence the environmental and economic effectiveness of the climate regime. We compare three different historical baseline methods and one innovative dynamic model baseline approach to appraise their applicability under a future REDD policy framework using a weighted multi-criteria analysis.  相似文献   

Interpretation of carbon dioxide diffusion behavior in coals   总被引：3，自引：1，他引：3  

Nikolai Siemons  Karl-Heinz A.A. Wolf  Johannes Bruining 《International Journal of Coal Geology》2007,72(3-4):315-324

Storage of carbon dioxide in geological formations is for many countries one of the options to reduce greenhouse gas emissions and thus to satisfy the Kyoto agreements. The CO₂ storage in unminable coal seams has the advantage that it stores CO₂ emissions from industrial processes and can be used to enhance coalbed methane recovery (CO₂-ECBM). For this purpose, the storage capacity of coal is an important reservoir parameter. While the amount of CO₂ sorption data on various natural coals has increased in recent years, only few measurements have been performed to estimate the rate of CO₂ sorption under reservoir conditions. An understanding of gas transport is crucial for processes associated with CO₂ injection, storage and enhanced coalbed methane (ECBM) production.A volumetric experimental set-up has been used to determine the rate of sorption of carbon dioxide in coal particles at various pressures and various grain size fractions. The pressure history during each pressure step was measured. The measurements are interpreted in terms of temperature relaxation and transport/sorption processes within the coal particles. The characteristic times of sorption increase with increasing pressure. No clear dependence of the characteristic time with respect to the particle size was found. At low pressures (below 1 MPa) fast gas diffusion is the prevailing mechanism for sorption, whereas at higher pressures, the slow diffusion process controls the gas uptake by the coal.  相似文献   

Crystallization and very rapid exhumation of the youngest Alpine eclogites (Tauern Window,Eastern Alps) from Rb/Sr mineral assemblage analysis   总被引：1，自引：0，他引：1  

Johannes?GlodnyEmail author  Uwe?Ring  Alexander?Kühn  Philipp?Gleissner  Gerhard?Franz 《Contributions to Mineralogy and Petrology》2005,149(6):699-712

Multimineral Rb/Sr internal isochrons from eclogite facies rocks of the Eclogite Zone (Tauern Window, Eastern Alps) consistently yield an Early Oligocene age of 31.5±0.7 Ma. This age has been obtained both for late-prograde, dehydration-related eclogitic veins, and for rocks variably deformed and recrystallized under eclogite facies conditions (2.0–2.5 GPa, 600°C). Initial Sr-isotopic equilibria among all phases indicate absence of significant post-eclogitic isotope redistribution processes, therefore the ages date eclogite facies assemblage crystallization. Equilibria also prove that no prolonged pre-eclogite facies history is recorded in the rocks. Instead, subduction, prograde mineral reactions, and eclogitization proceeded rapidly. Fast exhumation immediately after eclogitization, with minimum rates >36 mm/a is inferred from a 31.5±0.5 Ma internal mineral isochron age of a post-eclogitic greenschist facies vein assemblage. Such rates equal typical subduction rates. Late Eocene to Early Oligocene subduction of the European continental margin, with subsequent rapid exhumation of high-pressure nappe complexes has previously been recognized only in the Western Alps. The new data signify synchronous continental collision all along the Alpine belt. Our results demonstrate the unique potential of Rb/Sr assemblage system analysis for precise dating of both eclogite facies and post-eclogitic events, thus for precisely constraining exhumation rates of deep-seated rocks, and for straightforward linkage of petrologic evidence with isotopic ages.  相似文献   

Reviews     

Peter R. Odell  Seiya Uyeda  V. P. Zenkovich  C. Koeman  Johannes Ulrich  Maurice K.-Seguin  K. Gerke  U. Vetter  G. T. W. Wittmann  H. J. Habing  J. Gentilli 《GeoJournal》1980,1(1):95-100

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