scholarly journals Dynamic Ecological System Measures

2018 ◽  
Author(s):  
Huseyin Coskun
Keyword(s):  
System Analysis ◽  
Interspecific Interactions ◽  
Flow Distribution ◽  
Ecological System ◽  
Mathematical Framework ◽  
Activity Levels ◽  
Holistic View ◽  
Network Analyses ◽  
Dynamic Measures ◽  
Ecological Science

The system decomposition theory has recently been developed for the dynamic analysis of nonlinear compartmental systems. The application of this theory to the ecosystem analysis has also been introduced in a separate article. Based on this methodology, multiple new dynamic ecological system measures and indices of matrix, vector, and scalar types are systematically introduced in the present paper. These mathematical system analysis tools are quantitative ecological indicators that monitor the flow distribution and storage organization, quantify the direct, indirect, acyclic, cycling, and transfer (diact) effects and utilities of one compartment on another, identify the system efficiencies and stress, measure the compartmental exposures to system flows, determine the residence times and compartmental activity levels, and ascertain the system resilience and resistance in the case of disturbances. The proposed dynamic system measures and indices, thus, extract detailed information about ecosystems' characteristics, as well as their functions, properties, behaviors, and various other system attributes that are potentially hidden in and even obscured by data. A dynamic technique for the quantitative characterization and classification of main interspecific interactions and the determination of their strength within food webs is also developed based on the diact effect and utility indices. Moreover, major concepts and quantities in the current static network analyses are also extended to nonlinear dynamic settings and integrated with the proposed dynamic measures and indices in this unifying mathematical framework. Therefore, the proposed methodology enables a holistic view and analysis of ecological systems. We consider that the proposed methodology brings a novel complex system theory to the service of urgent and challenging environmental problems of the day and has the potential to lead the way to a more formalistic ecological science.

scholarly journals Static Ecological System Measures

2018 ◽  
Author(s):  
Huseyin Coskun
Keyword(s):  
System Analysis ◽  
Interspecific Interactions ◽  
Flow Distribution ◽  
Ecological Systems ◽  
Ecological System ◽  
Mathematical Framework ◽  
Activity Levels ◽  
Holistic View ◽  
Network Analyses ◽  
Comprehensive Framework

A new mathematical method for the static analysis of ecological systems has recently been developed by the author and was presented in a separate article. Based on this methodology, multiple new ecological system measures and indices of matrix, vector, and scalar types are systematically introduced in the present paper. These mathematical system analysis tools are quantitative ecological indicators that monitor the flow distribution and storage organization, quantify the direct, indirect, acyclic, cycling, and transfer (diact) effects and utilities of one compartment-- directly or indirectly--on another, and determine the residence times and compartmental activity levels. Major flow- and stock-related concepts and quantities of the current static network analyses are also integrated with the proposed measures and indices within this novel and unifying mathematical framework. This comprehensive framework enables a holistic view and analysis of static ecological systems. A quantitative technique for the classification and characterization of interspecific interactions and the determination of their strength within food webs is also developed. The proposed methodology allows for both input- and output-oriented analyses of ecological networks. The holistic perspective of the proposed methodology is extended further from the input-oriented to the output-oriented analysis. The proposed system measures and indices, thus, extract detailed information about ecosystems's characteristics, as well as their functions, properties, behaviors, and various other system attributes that are potentially hidden in and even obscured by data.

scholarly journals Dynamic Ecological System Analysis

2018 ◽  
Author(s):  
Huseyin Coskun
Keyword(s):  
Dynamic System ◽  
Nonlinear Dynamic ◽  
System Analysis ◽  
Interspecific Interactions ◽  
Mathematical Framework ◽  
Holistic View ◽  
Quantitative Classification ◽  
Network Analyses ◽  
Compartmental Systems ◽  
Dynamic Measures

This article develops a new mathematical method for holistic analysis of nonlinear dynamic compartmental systems through the system decomposition theory. The method is based on the novel dynamic system and subsystem partitioning methodologies through which compartmental systems are decomposed to the utmost level. The dynamic system and subsystem partitioning enable tracking the evolution of the initial stocks, environmental inputs, and intercompartmental system flows, as well as the associated storages derived from these stocks, inputs, and flows individually and separately within the system. Moreover, the transient and the dynamic direct, indirect, acyclic, cycling, and transfer (diact) flows and associated storages transmitted along a given flow path or from one compartment, directly or indirectly, to any other are analytically characterized, systematically classified, and mathematically formulated. Further, the article develops a dynamic technique based on the diact transactions for the quantitative classification of interspecific interactions and the determination of their strength within food webs. Major concepts and quantities of the current static network analyses are also extended to nonlinear dynamic settings and integrated with the proposed dynamic measures and indices within the proposed unifying mathematical framework. Therefore, the proposed methodology enables a holistic view and analysis of ecological systems. We consider that this methodology brings a novel complex system theory to the service of urgent and challenging environmental problems of the day and has the potential to lead the way to a more formalistic ecological science.

scholarly journals Static Ecological System Analysis

2018 ◽  
Author(s):  
Huseyin Coskun
Keyword(s):  
System Analysis ◽  
Interspecific Interactions ◽  
Ecological Systems ◽  
Mathematical Framework ◽  
The Novel ◽  
Holistic View ◽  
Network Analyses ◽  
Input And Output ◽  
Compartmental Systems

In this article, a new mathematical method for static analysis of compartmental systems is developed in the context of ecology. The method is based on the novel system and subsystem partitioning methodologies through which compartmental systems are decomposed to the utmost level. That is, the distribution of environmental inputs and intercompartmental system flows, as well as the organization of the associated storages generated by these flows within the system is determined individually and separately. Moreover, the transient and the static direct, indirect, acyclic, cycling, and transfer (diact) flows and associated storages transmitted along a given flow path or from one compartment, directly or indirectly, to any other are analytically characterized, systematically classified, and mathematically formulated. A quantitative technique for the categorization of interspecific interactions and the determination of their strength within food webs is also developed based on the diact transactions. The proposed methodology allows for both input- and output-oriented analyses of static ecological networks. The input- and output-oriented analyses are introduced within the proposed mathematical framework and their duality is demonstrated. Major flow- and stock-related concepts and quantities of the current static network analyses are also integrated with the proposed measures and indices within this unifying framework. This comprehensive methodology enables a holistic view and analysis of ecological systems.

scholarly journals Ant-mediated seed dispersal in a warmed world

2013 ◽  
Author(s):  
Katharine L. Stuble ◽  
Courtney M. Patterson ◽  
Mariano A. Rodriguez-Cabal ◽  
Relena R. Ribbons ◽  
Robert R. Dunn ◽  
...  
Keyword(s):  
Climate Change ◽  
Seed Dispersal ◽  
Interspecific Interactions ◽  
Forest Site ◽  
Activity Levels ◽  
Seed Removal ◽  
Experimental Warming ◽  
Climatic Warming ◽  
Plant Seed ◽  
Species Specific

Climate change affects communities both directly and indirectly via changes in interspecific interactions. One such interaction that may be altered under climate change is the ant-plant seed dispersal mutualism common in deciduous forests of the eastern US. As climatic warming alters the abundance and activity levels of ants, the potential exists for shifts in rates of ant-mediated seed removal. We used an experimental temperature manipulation at two sites in the eastern US (Harvard Forest in Massachusetts and Duke Forest in North Carolina) to examine the potential impacts of climatic warming on overall rates of seed dispersal (using Asarum canadense seeds) as well as species-specific rates of seed dispersal at the Duke Forest site. We also examined the relationship between ant critical thermal maxima (CTmax) and the mean seed removal temperature for each ant species. We found that seed removal rates did not change as a result of experimental warming at either study site, nor were there any changes in species-specific rates of seed dispersal. There was, however, a positive relationship between CTmax and mean seed removal temperature, whereby species with higher CTmax removed more seeds at hotter temperatures. The temperature at which seeds were removed was influenced by experimental warming as well as diurnal and day-to-day fluctuations in temperature. Taken together, our results suggest that while temperature may play a role in regulating seed removal by ants, ant plant seed-dispersal mutualisms may be more robust to climate change than currently assumed.

Methodology Development for Transient Flow Distribution Analysis in High Temperature Gas-Cooled Reactor

2020 ◽  
Author(s):  
Takeshi Aoki ◽  
Hiroyuki Sato ◽  
Hirofumi Ohashi
Keyword(s):  
High Temperature ◽  
Hydraulic System ◽  
System Analysis ◽  
Molecular Diffusion ◽  
Transient Flow ◽  
Flow Distribution ◽  
Distribution Analysis ◽  
Design Improvement ◽  
Air Ingress ◽  
High Temperature Gas

Abstract In the thermal hydraulic design of the prismatic-type of the high temperature gas cooled reactor (HTGR), unintended flows such as gap flows between columns, cross flows between column layers and gap flows between permanent reflectors should be analyzed to minimizing the unintended flows. The flow distribution considering unintended flows in the reactor has been evaluated for steady and conservative condition. On the other hand, the transient thermal hydraulic analysis for satisfactorily realistic conditions will be helpful for the design improvement of prismatic-type HTGR. The present study aims to improve the thermal hydraulic system analysis code developed by Japan Atomic Energy Agency based on the RELAP5/MOD3 code and confirm its applicability for the transient flow distribution analysis for prismatic-type HTGRs during anticipated operational occurrences and accidents for its design improvement utilizing experiences on high temperature engineering test reactor (HTTR) design. The calculation model and code were developed and validated to evaluate the detailed flowrate distribution considering the unintended flows in the core and the molecular diffusion that is important to analyze beginning air ingress behavior in an air ingress accident triggered by a rupture of a primary coolant piping in HTGR. It is concluded that a prospect has confirmed to apply the improved thermal hydraulic system analysis code for transient flow distribution analysis for prismatic-type HTGRs.

scholarly journals The architecture of co-morbidity networks of physical and mental health conditions in military veterans

2020 ◽  
Vol 476 (2239) ◽  
pp. 20190790
Author(s):  
Aaron F. Alexander-Bloch ◽  
Armin Raznahan ◽  
Russell T. Shinohara ◽  
Samuel R. Mathias ◽  
Harini Bathulapalli ◽  
...  
Keyword(s):  
System Analysis ◽  
Systems Of Care ◽  
Military Veterans ◽  
Psychiatric Morbidity ◽  
Psychological Trauma ◽  
Trauma Network ◽  
Targeted Interventions ◽  
Network Analyses ◽  
Co Morbidity ◽  
Psychiatric Conditions

Co-morbidity between medical and psychiatric conditions is commonly considered between individual pairs of conditions. However, an important alternative is to consider all conditions as part of a co-morbidity network, which encompasses all interactions between patients and a healthcare system. Analysis of co-morbidity networks could detect and quantify general tendencies not observed by smaller-scale studies. Here, we investigate the co-morbidity network derived from longitudinal healthcare records from approximately 1 million United States military veterans, a population disproportionately impacted by psychiatric morbidity and psychological trauma. Network analyses revealed marked and heterogenous patterns of co-morbidity, including a multi-scale community structure composed of groups of commonly co-morbid conditions. Psychiatric conditions including posttraumatic stress disorder were strong predictors of future medical morbidity. Neurological conditions and conditions associated with chronic pain were particularly highly co-morbid with psychiatric conditions. Across conditions, the degree of co-morbidity was positively associated with mortality. Co-morbidity was modified by biological sex and could be used to predict future diagnostic status, with out-of-sample prediction accuracy of 90–92%. Understanding complex patterns of disease co-morbidity has the potential to lead to improved designs of systems of care and the development of targeted interventions that consider the broader context of mental and physical health.

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