title: A two-component phenomenology for homogeneous magnetohydrodynamic turbulence

authors: Oughton, Sean

subjects: mathematics

abstract: A one-point closure model for energy decay in three-dimensional magnetohydrodynamic (MHD) turbulence is developed. The model allows for influence of a large-scale magnetic field that may be of strength sufficient to induce Alfvén wave propagation effects, and takes into account components of turbulence in which either the wave-like character is negligible or is dominant. This two-component model evolves energy and characteristic length scales, and may be useful as a simple description of homogeneous MHD turbulent decay. In concert with spatial transport models, it can form the basis for approximate treatment of low-frequency plasma turbulence in a variety of solar, space, and astrophysical contexts.

text: A two-component phenomenology for homogeneous magnetohydrodynamic turbulence A one-point closure model for energy decay in three-dimensional magnetohydrodynamic (MHD) turbulence is developed. The model allows for influence of a large-scale magnetic field that may be of strength sufficient to induce Alfvén wave propagation effects, and takes into account components of turbulence in which either the wave-like character is negligible or is dominant. This two-component model evolves energy and characteristic length scales, and may be useful as a simple description of homogeneous MHD turbulent decay. In concert with spatial transport models, it can form the basis for approximate treatment of low-frequency plasma turbulence in a variety of solar, space, and astrophysical contexts.

year: 2006-04-21

title: Efficient Process Model Discovery Using Maximal Pattern Mining

authors: Liesaputra, Veronica

subjects: Science & Technology

abstract: In recent years, process mining has become one of the most important and promising areas of research in the field of business process management as it helps businesses understand, analyze, and improve their business processes. In particular, several proposed techniques and algorithms have been proposed to discover and construct process models from workflow execution logs (i.e., event logs). With the existing techniques, mined models can be built based on analyzing the relationship between any two events seen in event logs. Being restricted by that, they can only handle special cases of routing constructs and often produce unsound models that do not cover all of the traces seen in the log. In this paper, we propose a novel technique for process discovery using Maximal Pattern Mining (MPM) where we construct patterns based on the whole sequence of events seen on the traces—ensuring the soundness of the mined models. Our MPM technique can handle loops (of any length), duplicate tasks, non-free choice constructs, and long distance dependencies. Our evaluation shows that it consistently achieves better precision, replay fitness and efficiency than the existing techniques.

text: Efficient Process Model Discovery Using Maximal Pattern Mining In recent years, process mining has become one of the most important and promising areas of research in the field of business process management as it helps businesses understand, analyze, and improve their business processes. In particular, several proposed techniques and algorithms have been proposed to discover and construct process models from workflow execution logs (i.e., event logs). With the existing techniques, mined models can be built based on analyzing the relationship between any two events seen in event logs. Being restricted by that, they can only handle special cases of routing constructs and often produce unsound models that do not cover all of the traces seen in the log. In this paper, we propose a novel technique for process discovery using Maximal Pattern Mining (MPM) where we construct patterns based on the whole sequence of events seen on the traces—ensuring the soundness of the mined models. Our MPM technique can handle loops (of any length), duplicate tasks, non-free choice constructs, and long distance dependencies. Our evaluation shows that it consistently achieves better precision, replay fitness and efficiency than the existing techniques.

year: 2015

title: Can large taonga bivalves speed up recovery in degraded estuaries?

authors: Prinz, Natalie

abstract: THE QUESTION:
Will there introduction of adult, long-lived bivalves with differing functional traits speed up recovery of degraded soft sediment habitats in estuaries?
RESULTS:
Average bivalve survival after one year was 18% in + tuangi plot sand 59% in + hanikura plots. Sediment oxygen consumption (SOC) after one month was enhanced by 116% in treatments containing tuangi compared to control treatments. After one year those were similar to ambient levels, still showed higher SOC than control plots.

text: Can large taonga bivalves speed up recovery in degraded estuaries? THE QUESTION:
Will there introduction of adult, long-lived bivalves with differing functional traits speed up recovery of degraded soft sediment habitats in estuaries?
RESULTS:
Average bivalve survival after one year was 18% in + tuangi plot sand 59% in + hanikura plots. Sediment oxygen consumption (SOC) after one month was enhanced by 116% in treatments containing tuangi compared to control treatments. After one year those were similar to ambient levels, still showed higher SOC than control plots.

year: 2023