Increasing complexity of today’s software systems is one of the major challenges software engineers have to face. This is aggravated by the fact that formerly isolated systems have to be interconnected to more comple...Increasing complexity of today’s software systems is one of the major challenges software engineers have to face. This is aggravated by the fact that formerly isolated systems have to be interconnected to more complex systems, called System-of-Systems (SoS). Those systems are in charge to provide more functionality to the user than all of their independent sub-systems could do. Reducing the complexity of such systems is one goal of the software engineering paradigm called component-based software engineering (CBSE). CBSE enables the developers to treat individual sub-systems as components which interact via interfaces with a simulated environment. Thus those components can be developed and implemented independently from other components. After the implementation a system integrator is able to interconnect the components to a SoS. Despite this much-used approach it is possible to show that constraints, which are valid in an isolated sub-system, are broken after this system is integrated into a SoS. To emphasize this issue we developed a technique based on interconnected timed automata for modelling sub-systems and System-of-Systems in the model checking tool UPPAAL. The presented modelling technique allows it to verify the correctness of single sub-systems as well as the resulting SoS. Additionally we developed a tool which abstracts the complicated timed automata to an easy to read component based language with the goal to help system integrators building and verifying complex SoS.展开更多
Convex polyhedral cuprate clusters are being formed through lateral frustration when the a and c lattice parameters of the tetragonal ACuO2 infinite layer structure will become identical by substitution of a large cat...Convex polyhedral cuprate clusters are being formed through lateral frustration when the a and c lattice parameters of the tetragonal ACuO2 infinite layer structure will become identical by substitution of a large cation (A = Ba2+). However, the corner-shared CuO2 plaquettes of the infinite network suffer a topotactic rearrangement forming edge-connected units, for instance Cu18O24 cages (polyhedron notation [4641238]) with 2 compound (space group P4/ nmm) will be discussed. The possibility to construct a cuprate super-cage with m3m symmetry (polyhedron notation [4641242438]) is being reported. This super-cage still consists of edge-connected CuO2 plaquettes when fully decorated with copper ions, but with different curvatures, arranged in circles of 9.39 ? of diameter with 139.2° Cu-O-Cu antiferromagnetic super-exchange interaction. On the one hand, the realization of such a quite stable cuprate super-cage as a candidate for high-Tc superconductivity depends on whether a template of suitable size such as the cation or C(CH3)4 enables its formation, and on the other hand the cage can further be stabilized by highly charged cations located along the [111] direction. Synthesis options will be proposed based on suggested cage formation pathways. An X-ray powder pattern was calculated for a less dense cluster structure of Im3m space group with a lattice parameter of a = 14.938 ? and two formula units of Cu46O51 to facilitate future identification. Characteristic X-ray scattering features as identification tool were obtained when the electron distribution of the hollow polyhedron was approximated with electron density in a spherical shell.展开更多
Small-scale heterogeneity in the deep mantle is concentrated in the upper-mantle transition zone （TZ）, in the depth range 410-660 km and also at the bottom 250 km D＂ region. This encourages a more detailed investig...Small-scale heterogeneity in the deep mantle is concentrated in the upper-mantle transition zone （TZ）, in the depth range 410-660 km and also at the bottom 250 km D＂ region. This encourages a more detailed investigation of the potential for seismic reflectivity imaging by modelling heterogeneous structures in mantle convection models including phase transitions of the TZ and D＂ regions. We applied finite elements with variable spacing near the boundary layers in 2-D cylindrical geometry that allow for sufficient spatial resolution. We investigated several models including an extended Boussinesq （EBA） model, focused on the D＂ region, and a compressible （ALA） model for the TZ region. The results for the D＂ region show typical lens-shaped structures of post-perovskite （PPV） embedded in the perovskite （PV） background mantle, where the thickness of the lenses, at 200-400 km, strongly depends on the Clapeyron slope of the PV-PPV transition. A second phase transition （double crossing） occurs in case the core temperature is higher than the intercept temperature Ti. Our phase-dependent rheology results in contrasting effective viscosity between PV and PPV. Our model results reveal a distinctly clear mechanical weakening of the PPV lenses with about an order of magnitude lower viscosity. The shear wave-speed distributions computed from our convection results are strongly correlated with the heterogeneous distribution of the mineral phase. Gradients in the seismic wave-speed that are the target of seismological reflectivity imaging are clearly revealed. The wave-speed results show a clear resolution of the top and bottom interfaces of the PPV lenses. Our ALA model for the TZ is based on a thermodynamical model for the magnesium end- member of an olivine-pyroxene mantle. The model predicts a much more complex distribution of mineral phases, compared to our D＂ results, in agreement with the greater number of mineral phases involved in the olivine-pyroxene phase diagram for the P, T conditions of the transition zone. Near cold downwelling flows representing subducting lithospheric slabs, where the local geotherm can differ by up to 1 000 K from the horizontal average, and small-scale lateral variations in the mineral phases can occur.展开更多
Actual software development processes define the different steps developers have to perform during a development project. Usually these development steps are not described independently from each other—a more or less...Actual software development processes define the different steps developers have to perform during a development project. Usually these development steps are not described independently from each other—a more or less formal flow of development step is an essential part of the development process definition. In practice, we observe that often the process definitions are hardly used and very seldom “lived”. One reason is that the predefined general process flow does not reflect the specific constraints of the individual project. For that reasons we claim to get rid of the process flow definition as part of the development process. Instead we describe in this paper an approach to smartly assist developers in software process execution. The approach observes the developer’s actions and predicts his next development step based on the project process history. Therefore we apply machine learning resp. sequence learning approaches based on a general rule based process model and its semantics. Finally we show two evaluations of the presented approach: The data of the first is derived from a synthetic scenario. The second evaluation is based on real project data of an industrial enterprise.展开更多
Carbon capture and storage in deep geological formations is a method to reduce greenhouse gas emissions.Supercritical CO_(2) is injected into a reservoir and dissolves in the brine.Under the impact of pressure and tem...Carbon capture and storage in deep geological formations is a method to reduce greenhouse gas emissions.Supercritical CO_(2) is injected into a reservoir and dissolves in the brine.Under the impact of pressure and temperature(P-T)the aqueous species of the CO_(2)-acidified brine diffuse through the cap rock where they trigger CO_(2)-watererock interactions.These geochemical reactions result in mineral dissolution and precipitation along the CO_(2) migration path and are responsible for a change in porosity and therefore for the sealing capacity of the cap rock.This study focuses on the diffusive mass transport of CO_(2) along a gradient of decreasing PeT conditions.The process is retraced with a one-dimensional hydrogeochemical reactive mass transport model.The semigeneric hydrogeochemical model is based on chemical equilibrium thermodynamics.Based on a broad variety of scenarios,including different initial mineralogical,chemical and physical parameters,the hydrogeochemical parameters that are most sensitive for safe long-term CO_(2) storage are identified.The results demonstrate that PeT conditions have the strongest effect on the change in porosity and the effect of both is stronger at high PeT conditions because the solubility of the mineral phases involved depends on PeT conditions.Furthermore,modeling results indicate that the change in porosity depends strongly on the initial mineralogical composition of the reservoir and cap rock as well as on the brine compositions.Nevertheless,a wide range of conditions for safe CO_(2) storage is identified.展开更多
Introduction Plant phenotyping describes the result of the interaction of genotype with the environment[1].This is performed with high throughput in greenhouses by automated screening systems using different types of ...Introduction Plant phenotyping describes the result of the interaction of genotype with the environment[1].This is performed with high throughput in greenhouses by automated screening systems using different types of imaging and non-imaging sensors[2].The high-throughput imaging routines result in large amounts of data,which require sophisticated processing routines.Sharing and reusing phenotype-related data are not common,because its acquisition and processing are resource costly and technically intensive[3].展开更多
文摘Increasing complexity of today’s software systems is one of the major challenges software engineers have to face. This is aggravated by the fact that formerly isolated systems have to be interconnected to more complex systems, called System-of-Systems (SoS). Those systems are in charge to provide more functionality to the user than all of their independent sub-systems could do. Reducing the complexity of such systems is one goal of the software engineering paradigm called component-based software engineering (CBSE). CBSE enables the developers to treat individual sub-systems as components which interact via interfaces with a simulated environment. Thus those components can be developed and implemented independently from other components. After the implementation a system integrator is able to interconnect the components to a SoS. Despite this much-used approach it is possible to show that constraints, which are valid in an isolated sub-system, are broken after this system is integrated into a SoS. To emphasize this issue we developed a technique based on interconnected timed automata for modelling sub-systems and System-of-Systems in the model checking tool UPPAAL. The presented modelling technique allows it to verify the correctness of single sub-systems as well as the resulting SoS. Additionally we developed a tool which abstracts the complicated timed automata to an easy to read component based language with the goal to help system integrators building and verifying complex SoS.
文摘Convex polyhedral cuprate clusters are being formed through lateral frustration when the a and c lattice parameters of the tetragonal ACuO2 infinite layer structure will become identical by substitution of a large cation (A = Ba2+). However, the corner-shared CuO2 plaquettes of the infinite network suffer a topotactic rearrangement forming edge-connected units, for instance Cu18O24 cages (polyhedron notation [4641238]) with 2 compound (space group P4/ nmm) will be discussed. The possibility to construct a cuprate super-cage with m3m symmetry (polyhedron notation [4641242438]) is being reported. This super-cage still consists of edge-connected CuO2 plaquettes when fully decorated with copper ions, but with different curvatures, arranged in circles of 9.39 ? of diameter with 139.2° Cu-O-Cu antiferromagnetic super-exchange interaction. On the one hand, the realization of such a quite stable cuprate super-cage as a candidate for high-Tc superconductivity depends on whether a template of suitable size such as the cation or C(CH3)4 enables its formation, and on the other hand the cage can further be stabilized by highly charged cations located along the [111] direction. Synthesis options will be proposed based on suggested cage formation pathways. An X-ray powder pattern was calculated for a less dense cluster structure of Im3m space group with a lattice parameter of a = 14.938 ? and two formula units of Cu46O51 to facilitate future identification. Characteristic X-ray scattering features as identification tool were obtained when the electron distribution of the hollow polyhedron was approximated with electron density in a spherical shell.
基金supported by the CMG Program of NSF,Senior Visiting Professorship by the Chinese Academy of SciencesThe Netherlands Research Center for Integrated Solid Earth Science (ISES 3.2.5) and the 216 through ISES Project ME-2.7.
文摘Small-scale heterogeneity in the deep mantle is concentrated in the upper-mantle transition zone （TZ）, in the depth range 410-660 km and also at the bottom 250 km D＂ region. This encourages a more detailed investigation of the potential for seismic reflectivity imaging by modelling heterogeneous structures in mantle convection models including phase transitions of the TZ and D＂ regions. We applied finite elements with variable spacing near the boundary layers in 2-D cylindrical geometry that allow for sufficient spatial resolution. We investigated several models including an extended Boussinesq （EBA） model, focused on the D＂ region, and a compressible （ALA） model for the TZ region. The results for the D＂ region show typical lens-shaped structures of post-perovskite （PPV） embedded in the perovskite （PV） background mantle, where the thickness of the lenses, at 200-400 km, strongly depends on the Clapeyron slope of the PV-PPV transition. A second phase transition （double crossing） occurs in case the core temperature is higher than the intercept temperature Ti. Our phase-dependent rheology results in contrasting effective viscosity between PV and PPV. Our model results reveal a distinctly clear mechanical weakening of the PPV lenses with about an order of magnitude lower viscosity. The shear wave-speed distributions computed from our convection results are strongly correlated with the heterogeneous distribution of the mineral phase. Gradients in the seismic wave-speed that are the target of seismological reflectivity imaging are clearly revealed. The wave-speed results show a clear resolution of the top and bottom interfaces of the PPV lenses. Our ALA model for the TZ is based on a thermodynamical model for the magnesium end- member of an olivine-pyroxene mantle. The model predicts a much more complex distribution of mineral phases, compared to our D＂ results, in agreement with the greater number of mineral phases involved in the olivine-pyroxene phase diagram for the P, T conditions of the transition zone. Near cold downwelling flows representing subducting lithospheric slabs, where the local geotherm can differ by up to 1 000 K from the horizontal average, and small-scale lateral variations in the mineral phases can occur.
文摘Actual software development processes define the different steps developers have to perform during a development project. Usually these development steps are not described independently from each other—a more or less formal flow of development step is an essential part of the development process definition. In practice, we observe that often the process definitions are hardly used and very seldom “lived”. One reason is that the predefined general process flow does not reflect the specific constraints of the individual project. For that reasons we claim to get rid of the process flow definition as part of the development process. Instead we describe in this paper an approach to smartly assist developers in software process execution. The approach observes the developer’s actions and predicts his next development step based on the project process history. Therefore we apply machine learning resp. sequence learning approaches based on a general rule based process model and its semantics. Finally we show two evaluations of the presented approach: The data of the first is derived from a synthetic scenario. The second evaluation is based on real project data of an industrial enterprise.
基金We would like to thank the anonymous reviewers for their constructive reviews that considerably improved the manuscript.
文摘Carbon capture and storage in deep geological formations is a method to reduce greenhouse gas emissions.Supercritical CO_(2) is injected into a reservoir and dissolves in the brine.Under the impact of pressure and temperature(P-T)the aqueous species of the CO_(2)-acidified brine diffuse through the cap rock where they trigger CO_(2)-watererock interactions.These geochemical reactions result in mineral dissolution and precipitation along the CO_(2) migration path and are responsible for a change in porosity and therefore for the sealing capacity of the cap rock.This study focuses on the diffusive mass transport of CO_(2) along a gradient of decreasing PeT conditions.The process is retraced with a one-dimensional hydrogeochemical reactive mass transport model.The semigeneric hydrogeochemical model is based on chemical equilibrium thermodynamics.Based on a broad variety of scenarios,including different initial mineralogical,chemical and physical parameters,the hydrogeochemical parameters that are most sensitive for safe long-term CO_(2) storage are identified.The results demonstrate that PeT conditions have the strongest effect on the change in porosity and the effect of both is stronger at high PeT conditions because the solubility of the mineral phases involved depends on PeT conditions.Furthermore,modeling results indicate that the change in porosity depends strongly on the initial mineralogical composition of the reservoir and cap rock as well as on the brine compositions.Nevertheless,a wide range of conditions for safe CO_(2) storage is identified.
基金partially funded by the Deutsche Forschungsgemeinschaft(DFGGerman Research Foundation)under Germany’s Excellence Strategy—EXC 2070-390732324support by the Open Access Publishing Fund of Clausthal University of Technology.
文摘Introduction Plant phenotyping describes the result of the interaction of genotype with the environment[1].This is performed with high throughput in greenhouses by automated screening systems using different types of imaging and non-imaging sensors[2].The high-throughput imaging routines result in large amounts of data,which require sophisticated processing routines.Sharing and reusing phenotype-related data are not common,because its acquisition and processing are resource costly and technically intensive[3].
