Search results for " Modeling"

The headstarting technique is an ineffective method for conservation of the European pond turtle – elasticity analysis

2008

The European pond turtle ( Emys orbicularis ) is endangered in many areas within its distribution range. Thus, protection programmes for the turtle populations are in place. However, the efficiency of some techniques (including a highly manipulative one - headstarting) is questionable. Elasticity analysis was conducted using the life history data gathered in central Poland during the period 1986 - 2002. The analysis revealed that headstarting is a fairly ineffective method. The most effective methods are those that protect adult individuals. Thus, methods that can sustain a decreasing adult mortality rate should be recommended for turtle conservation.

UML/OCL-based modeling of work-based access control policies for collaborative healthcare systems

2016

A work-based access control (WBAC) model is proposed by introducing the team role concept and modifying the user-role assignment model from a previous work. The main goals of WBAC are flexibility, easy manageability, security, as well as suitability to support cooperative work of dynamic teams in healthcare environments. One of the major challenges of WBAC regards authorization constraints in terms of organizational policies. In this article, we show how Unified Modeling Language (UML) and Object Constraints Language (OCL) are utilized to design and analyze the authorization constraints of WBAC in cooperative engagements with complex scenarios in the collaborative healthcare domain. We also…

Modeling Requirements for Future CASE

1995

In this paper we discuss some requirements for future CASE Computer Aided Software/Systems Engineering environments. These requirements include increased modifiability and flexibility as well as support for process and agent models. We claim that they can only be addressed by developing more powerful representation and modeling techniques. As a possible basis for modeling various techniques, we outline a general information architecture for a future CASE environment. In addition, we propose primitive types for specifying techniques, the development process, and agent models, and use these types for modeling an example methodology and examine how the requirements are or can be supported in o…

Process support in MetaCASE: implementing the conceptual basis for enactable process models in MetaEdit+

2002

This study concerns the support of information system analysis and design process in a metaCASE environment. We see a process as highly, evolutionary and unstructural in nature, thus requiring the tailorability of user process models and their conceptual basis, process modelling language (PML). In addition to the flexibility needed for guiding various system developers, the CASE environment needs to be enacted using strictly defined environment actions. A distinction between user and environment processes is made, hence distinguishing also their conceptual basis and modelling requirements. The study depicts the realisation of the basic concepts and tools required in modelling a PML and the …

Optimization of the coagulation–flocculation treatment: influence of rapid mix parameters

1999

[EN] Turbid waters, containing suspended and colloidal particles, are normally treated by coagulation–flocculation followed by clarification; the process usually consists of the rapid dispersal of a coagulant into the raw water followed by an intense agitation commonly defined as rapid mixing. Rapid mixing is influenced by chemical and physical parameters and the final result of the whole treatment depends on this step. The study focused on the most important parameters of rapid mix design: velocity gradient and rapid mix time. Wastewaters from a tannery processing stored ovine hides were treated with aluminium(III) or iron(III) salts. Experimental results indicate that rapid mix time has a…

Comparative study of laboratory-scale thermophilic and mesophilic activated sludge processes.

2005

Laboratory-scale mesophilic (20-35 degrees C) and thermophilic (55 degrees C) activated sludge processes (ASPs) treating diluted molasses wastewater were compared in effluent quality, removal of different COD fractions, sludge yield, floc size, and sludge settleability. The effect of polyaluminium chloride (PAC) with high cationic charge on sludge settleability and effluent quality was also studied. In the ASPs, the hydraulic retention time was 12h in both processes, corresponding to a volumetric loading rate of 3.2+/-1.0 kg COD(filt) m(-3)d(-1). The mesophilic ASP gave 79+/-18% and 90+/-2% and the thermophilic ASP gave 50+/-6% and 67+/-11% total COD (COD(tot)) and GF/A-filtered COD (COD(fi…

Metamodel Specialization for DSL Tool Building

2016

Most of domain-specific tool building and especially diagram editor building nowadays involves some usage of metamodels. However normally the metamodel alone is not sufficient to define an editor. Frequently the metamodel just defines the abstract syntax of the domain, mappings or transformations are required to define the editor. Another approach [8] is based on a fixed type metamodel, there an editor definition consists of an instance of this metamodel to be executed by an engine. However there typically a number of functionality extensions in a transformation language is required. The paper offers a new approach based on metamodel specialization. First the metamodel specialization based …

Thermal and Hydrodynamic Analysis of the Melting Process in the Cold Crucible Using 3D Modeling

2008

The volume and composition of dead wood on traditional and forest fuel harvested clear-cuts

2010

Logging residue and cut stumps are increasingly used as a renewable energy source known as forest fuel. Forest fuel harvesting obviously reduces the volume of dead wood and is likely to alter the dead wood composition, but the magnitude of the change is not known. Such information is important for the evaluation of the effects of forest fuel harvesting on biodiversity because a large proportion of forest dwelling species are directly dependent on dead wood. We measured the volume and characteristics of all dead wood units with a minimum diameter of 2 cm and a minimum length of 20 cm on 10 forest-fuel harvested and 10 traditional (control) clear-cuts. The total volume of dead wood at forest …

A Novel Approach to Propagation Pattern Analysis in Intracardiac Atrial Fibrillation Signals

2010

The purpose of this study is to investigate propagation patterns in intracardiac signals recorded during atrial fibrillation (AF) using an approach based on partial directed coherence (PDC), which evaluates directional coupling between multiple signals in the frequency domain. The PDC is evaluated at the dominant frequency of AF signals and tested for significance using a surrogate data procedure specifically designed to assess causality. For significantly coupled sites, the approach allows also to estimate the delay in propagation. The methods potential is illustrated with two simulation scenarios based on a detailed ionic model of the human atrial myocyte as well as with real data recordi…