112 research outputs found
Responsible Composition and Optimization of Integration Processes under Correctness Preserving Guarantees
Enterprise Application Integration deals with the problem of connecting
heterogeneous applications, and is the centerpiece of current on-premise, cloud
and device integration scenarios. For integration scenarios, structurally
correct composition of patterns into processes and improvements of integration
processes are crucial. In order to achieve this, we formalize compositions of
integration patterns based on their characteristics, and describe optimization
strategies that help to reduce the model complexity, and improve the process
execution efficiency using design time techniques. Using the formalism of timed
DB-nets - a refinement of Petri nets - we model integration logic features such
as control- and data flow, transactional data storage, compensation and
exception handling, and time aspects that are present in reoccurring solutions
as separate integration patterns. We then propose a realization of optimization
strategies using graph rewriting, and prove that the optimizations we consider
preserve both structural and functional correctness. We evaluate the
improvements on a real-world catalog of pattern compositions, containing over
900 integration processes, and illustrate the correctness properties in case
studies based on two of these processes.Comment: 37 page
trans-Ethylenedi-p-phenylene diacetate
The centrosymmetric title compound, C18H26O4, was prepared in high yield from 4-acetoxystyrene via Ru-catalysed homo-olefin metathesis. Exclusive formation of the E-configurated isomer was observed. In the crystal, a strong C—H⋯π intermolecular interaction links the molecules together
trans-1,2-Bis(3,5-dimethoxyphenyl)ethene
The title compound, C18H20O4, was prepared in high yield from 3,5-dimethoxystyrene via a Ru-catalysed homo-olefin metathesis. Exclusive formation of the E-configurated isomer was observed. Interestingly, one symmetric unit contains two molecules adopting an s-syn-anti and and an all-s-anti conformation
Small‐scale heterogeneity shapes grassland diversity in low‐to‐intermediate resource environments
Questions
Soil resource heterogeneity influences the outcome of plant–plant interactions and, consequently, species co-existence and diversity patterns. The magnitude and direction of heterogeneity effects vary widely, and the processes underlying such variations are not fully understood. In this study, we explored how and under what resource conditions small-scale heterogeneity modulates grassland plant diversity.
Location
Oderhänge Mallnow, Potsdam, Brandenburg, Germany.
Methods
We expanded the individual-based plant community model (IBC-grass) to incorporate dynamic below-ground resource maps, simulating spatial heterogeneity of resource availability. Empirical centimeter-scale data of soil C/N ratio were integrated into the model, accounting for both configurational and compositional heterogeneity. We then analyzed the interplay between small-scale heterogeneity and resource availability on the interaction and co-existence of plant species and overall diversity.
Results
Our results showed significant differences between the low- and high-resource scenarios, with both configurational and compositional heterogeneity having a positive effect on species richness and Simpson's diversity, but only under low-resource conditions. As compositional heterogeneity in the fine-scale C/N ratio increased, we observed a positive shift in Simpson's diversity and species richness, with the highest effects at the highest level of variability tested. We observed little to no effect in nutrient-rich scenarios, and a shift to negative effects at the intermediate resource level. The study demonstrates that site-specific resource levels underpin how fine-scale heterogeneity influences plant diversity and species co-existence, and partly explains the divergent effects recorded in different empirical studies.
Conclusions
This study provides mechanistic insights into the complex relationship between resource heterogeneity and diversity patterns. It highlights the context-dependent effects of small-scale heterogeneity, which can be positive under low-resource, neutral under high-resource, and negative under intermediate-resource conditions. These findings provide a foundation for future investigations into small-scale heterogeneity–diversity relationships, contributing to a deeper understanding of the processes that promote species co-existence in plant communities
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