The paper discusses conjectures concerning patterns in virus spread observed in the Covid-19 even... more The paper discusses conjectures concerning patterns in virus spread observed in the Covid-19 event, including fluctuations of activity under constant environmental conditions, plateaus of near-constant activity, and rapid wild-type replacement at rather low levels of population immunity. Based on models of time-variant networks, it is shown that the patterns can be explained if spread dynamics result from superposition of three components: Continuous activity in reservoirs with limited fluctuation where fluctuation of group members allows transmissions from active cases to new arrivals before the active cases leave or reach the end of the contagious period. Hospitals are the obvious candidates for these reservoirs. The second component is propagation within stable groups, such as families, office staff, or religious groups. In addition, there are outbursts in temporary groups. The second and third components multiply case numbers but, due to strong segmentation of the population, do...
The paper presents models of the dynamics of virus spread in scenarios where social contacts are ... more The paper presents models of the dynamics of virus spread in scenarios where social contacts are severely reduced but contact networks in some fractions of the population are fairly resilient. It is demonstrated that this can result in the existence of multiple meta-stable states and changes of environmental constraints trigger transition from one such state to another but fail to cause reduction of activity beyond the level of the target state.
The paper presents a two-step approach for DSM-based generat-ing of substantial parts of tools fo... more The paper presents a two-step approach for DSM-based generat-ing of substantial parts of tools for legacy-system analysis. In the first step a parser is generated from a formal grammar, represent-ing the syntax of the legacy system's code. This parser is able to recognize the constructs of the legacy code but unaware of any analytic functionality. In the second step the code for the analytic functionality and glue code for integrating the parser-generated code into a framework is generated from a domain-specific model capturing properties of and relations between code constructs to be analyzed. Integration with parser functionality generated in first step and framework is achieved by loading classes and re-trieving information using reflection and annotations in the second step.
Abstract. Model driven development may be based on different model semantics. This paper compares... more Abstract. Model driven development may be based on different model semantics. This paper compares two alternatives. The first of these alternatives conceives of models as representations of computational systems on different levels of abstraction. According to this approach, the development is a process of refinement and completion. An alternative approach uses domain specific meta-models to shift perspective from software design towards an analysis of the environment where the software is to be used. This approach combines concepts from logic programming and domain specific development. Model elements describe aspects of the environment directly, not indirectly by definition of their representation in a computational system. However, the use of models with declarative semantics is restricted to a representation of specific aspects of scenarios that vary within the domain. This fragmentary declarative information is evaluated by an intelligent functionality of a domain-specific meta...
The invention relates to a device for separating the bulk material present small parts made of ma... more The invention relates to a device for separating the bulk material present small parts made of magnetic material. Distinguishing invention is particularity that are raised to be separated portions by a modulated magnetic field and collected on a cover plate. In this case, is achieved by modulating the intensity of magnetic field, that parts are held in a desired final position on this, while parts which have come to a standstill in an undesirable position, drop back in Down regulation of the magnetic field. This ensures that the ultimately collected on the top plate parts have a certain position and orientation.
Possible architectures for meta-models for domain specific model driven development are compared ... more Possible architectures for meta-models for domain specific model driven development are compared in the context of a domain-exploration engines for patterns in the dynamics of financial markets-that require interaction between domain expert and model, continuous development of the meta-model and yield the necessity to provide the domain expert with means to express rather abstract mathematical concepts. The focus will be on the decisions for structural integration versus dynamic integration, and for integration within an object oriented meta-model versus integration by mapping between formal grammars. It will be argued that structural integration within an object oriented meta-model is the most promising approach for the particular task.
Possible architectures for meta-models for domain specific model driven development are compared ... more Possible architectures for meta-models for domain specific model driven development are compared in the context of a domain – exploration engines for patterns in the dynamics of financial markets – that require interaction between domain expert and model, continuous development of the meta-model and yield the necessity to provide the domain expert with means to express rather abstract mathematical concepts. The focus will be on the decisions for structural integration versus dynamic integration, and for integration within an object oriented meta-model versus integration by mapping between formal grammars. It will be argued that structural integration within an object oriented meta-model is the most promising approach for the particular task.
Model driven development may be based on different model semantics. This paper compares two alter... more Model driven development may be based on different model semantics. This paper compares two alternatives. The first of these alternatives conceives of models as representations of computational systems on different levels of abstraction. According to this approach, the development is a process of refinement and completion. An alternative approach uses domain specific meta-models to shift perspective from software design towards an analysis of the environment where the software is to be used. This approach combines concepts from logic programming and domain specific development. Model elements describe aspects of the environment directly, not indirectly by definition of their representation in a computational system. However, the use of models with declarative semantics is restricted to a representation of specific aspects of scenarios that vary within the domain. This fragmentary declarative information is evaluated by an intelligent functionality of a domain-specific meta-model for...
The paper presents models of the dynamics of virus spread in scenarios where social contacts are ... more The paper presents models of the dynamics of virus spread in scenarios where social contacts are severely reduced but contact networks in some fractions of the population are fairly resilient. It is demonstrated that this can result in the existence of multiple meta-stable states and changes of environmental constraints trigger transition from one such state to another but fail to cause reduction of activity beyond the level of the target state.
Model driven development may be based on different model semantics. This paper compares two alter... more Model driven development may be based on different model semantics. This paper compares two alternatives. The first of these alternatives conceives of models as representations of computational systems on different levels of abstraction. According to this approach, the development is a process of refinement and completion. An alternative approach uses domain specific meta-models to shift perspective from software design towards an analysis of the environment where the software is to be used. This approach combines concepts from logic programming and domain specific development. Model elements describe aspects of the environment directly, not indirectly by definition of their representation in a computational system. However, the use of models with declarative semantics is restricted to a representation of specific aspects of scenarios that vary within the domain. This fragmentary declarative information is evaluated by an intelligent functionality of a domain-specific meta-model for instantiation of a domain-specific application template.
Model driven development may be based on different model semantics. This paper compares two alter... more Model driven development may be based on different model semantics. This paper compares two alternatives. The first of these alternatives conceives of models as representations of computational systems on different levels of abstraction. According to this approach, the development is a process of refinement and completion. An alternative approach uses domain specific meta-models to shift perspective from software design towards an analysis of the environment where the software is to be used. This approach combines concepts from logic programming and domain specific development. Model elements describe aspects of the environment directly, not indirectly by definition of their representation in a computational system. However, the use of models with declarative semantics is restricted to a representation of specific aspects of scenarios that vary within the domain. This fragmentary declarative information is evaluated by an intelligent functionality of a domain-specific meta-model for instantiation of a domain-specific application template.
The paper discusses conjectures concerning patterns in virus spread observed in the Covid-19 even... more The paper discusses conjectures concerning patterns in virus spread observed in the Covid-19 event, including fluctuations of activity under constant environmental conditions, plateaus of near-constant activity, and rapid wild-type replacement at rather low levels of population immunity. Based on models of time-variant networks, it is shown that the patterns can be explained if spread dynamics result from superposition of three components: Continuous activity in reservoirs with limited fluctuation where fluctuation of group members allows transmissions from active cases to new arrivals before the active cases leave or reach the end of the contagious period. Hospitals are the obvious candidates for these reservoirs. The second component is propagation within stable groups, such as families, office staff, or religious groups. In addition, there are outbursts in temporary groups. The second and third components multiply case numbers but, due to strong segmentation of the population, do...
The paper presents models of the dynamics of virus spread in scenarios where social contacts are ... more The paper presents models of the dynamics of virus spread in scenarios where social contacts are severely reduced but contact networks in some fractions of the population are fairly resilient. It is demonstrated that this can result in the existence of multiple meta-stable states and changes of environmental constraints trigger transition from one such state to another but fail to cause reduction of activity beyond the level of the target state.
The paper presents a two-step approach for DSM-based generat-ing of substantial parts of tools fo... more The paper presents a two-step approach for DSM-based generat-ing of substantial parts of tools for legacy-system analysis. In the first step a parser is generated from a formal grammar, represent-ing the syntax of the legacy system's code. This parser is able to recognize the constructs of the legacy code but unaware of any analytic functionality. In the second step the code for the analytic functionality and glue code for integrating the parser-generated code into a framework is generated from a domain-specific model capturing properties of and relations between code constructs to be analyzed. Integration with parser functionality generated in first step and framework is achieved by loading classes and re-trieving information using reflection and annotations in the second step.
Abstract. Model driven development may be based on different model semantics. This paper compares... more Abstract. Model driven development may be based on different model semantics. This paper compares two alternatives. The first of these alternatives conceives of models as representations of computational systems on different levels of abstraction. According to this approach, the development is a process of refinement and completion. An alternative approach uses domain specific meta-models to shift perspective from software design towards an analysis of the environment where the software is to be used. This approach combines concepts from logic programming and domain specific development. Model elements describe aspects of the environment directly, not indirectly by definition of their representation in a computational system. However, the use of models with declarative semantics is restricted to a representation of specific aspects of scenarios that vary within the domain. This fragmentary declarative information is evaluated by an intelligent functionality of a domain-specific meta...
The invention relates to a device for separating the bulk material present small parts made of ma... more The invention relates to a device for separating the bulk material present small parts made of magnetic material. Distinguishing invention is particularity that are raised to be separated portions by a modulated magnetic field and collected on a cover plate. In this case, is achieved by modulating the intensity of magnetic field, that parts are held in a desired final position on this, while parts which have come to a standstill in an undesirable position, drop back in Down regulation of the magnetic field. This ensures that the ultimately collected on the top plate parts have a certain position and orientation.
Possible architectures for meta-models for domain specific model driven development are compared ... more Possible architectures for meta-models for domain specific model driven development are compared in the context of a domain-exploration engines for patterns in the dynamics of financial markets-that require interaction between domain expert and model, continuous development of the meta-model and yield the necessity to provide the domain expert with means to express rather abstract mathematical concepts. The focus will be on the decisions for structural integration versus dynamic integration, and for integration within an object oriented meta-model versus integration by mapping between formal grammars. It will be argued that structural integration within an object oriented meta-model is the most promising approach for the particular task.
Possible architectures for meta-models for domain specific model driven development are compared ... more Possible architectures for meta-models for domain specific model driven development are compared in the context of a domain – exploration engines for patterns in the dynamics of financial markets – that require interaction between domain expert and model, continuous development of the meta-model and yield the necessity to provide the domain expert with means to express rather abstract mathematical concepts. The focus will be on the decisions for structural integration versus dynamic integration, and for integration within an object oriented meta-model versus integration by mapping between formal grammars. It will be argued that structural integration within an object oriented meta-model is the most promising approach for the particular task.
Model driven development may be based on different model semantics. This paper compares two alter... more Model driven development may be based on different model semantics. This paper compares two alternatives. The first of these alternatives conceives of models as representations of computational systems on different levels of abstraction. According to this approach, the development is a process of refinement and completion. An alternative approach uses domain specific meta-models to shift perspective from software design towards an analysis of the environment where the software is to be used. This approach combines concepts from logic programming and domain specific development. Model elements describe aspects of the environment directly, not indirectly by definition of their representation in a computational system. However, the use of models with declarative semantics is restricted to a representation of specific aspects of scenarios that vary within the domain. This fragmentary declarative information is evaluated by an intelligent functionality of a domain-specific meta-model for...
The paper presents models of the dynamics of virus spread in scenarios where social contacts are ... more The paper presents models of the dynamics of virus spread in scenarios where social contacts are severely reduced but contact networks in some fractions of the population are fairly resilient. It is demonstrated that this can result in the existence of multiple meta-stable states and changes of environmental constraints trigger transition from one such state to another but fail to cause reduction of activity beyond the level of the target state.
Model driven development may be based on different model semantics. This paper compares two alter... more Model driven development may be based on different model semantics. This paper compares two alternatives. The first of these alternatives conceives of models as representations of computational systems on different levels of abstraction. According to this approach, the development is a process of refinement and completion. An alternative approach uses domain specific meta-models to shift perspective from software design towards an analysis of the environment where the software is to be used. This approach combines concepts from logic programming and domain specific development. Model elements describe aspects of the environment directly, not indirectly by definition of their representation in a computational system. However, the use of models with declarative semantics is restricted to a representation of specific aspects of scenarios that vary within the domain. This fragmentary declarative information is evaluated by an intelligent functionality of a domain-specific meta-model for instantiation of a domain-specific application template.
Model driven development may be based on different model semantics. This paper compares two alter... more Model driven development may be based on different model semantics. This paper compares two alternatives. The first of these alternatives conceives of models as representations of computational systems on different levels of abstraction. According to this approach, the development is a process of refinement and completion. An alternative approach uses domain specific meta-models to shift perspective from software design towards an analysis of the environment where the software is to be used. This approach combines concepts from logic programming and domain specific development. Model elements describe aspects of the environment directly, not indirectly by definition of their representation in a computational system. However, the use of models with declarative semantics is restricted to a representation of specific aspects of scenarios that vary within the domain. This fragmentary declarative information is evaluated by an intelligent functionality of a domain-specific meta-model for instantiation of a domain-specific application template.
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