The Financial Accounting Model from a System Dynamics' Perspective

This paper explores the foundation of the financial accounting model. We examine the properties of the accounting equation as the principal algorithm for the design and the development of a System Dynamics model. Key to the perspective is the foundational requirement that resolves the temporal conflict that resides in a stock and flow model. Through formal analysis the accounting equation is redefined as a cybernetic model by expressing the temporal and dynamic properties of its terms. Articulated in that form the accounting equation is enabled to be defined as a dynamic stock and flow model expressing the two dimensions of the double-entry accounting system. With that formal foundation it is argued that the accounting model is capable to simulate financial dynamics as well as be integrated with models that express operational and world dynamics. Thus we prove that it is possible to design and build a dynamic business model that can meet requirements of management accounting (ex ante, before the fact) as well as financial accounting (ex post, after the fact). We conclude that the dynamic accounting model can be made relevant for strategic planning and control purposes and be integrated within a System Dynamics model designed for such purposes.dynamic accounting model, accounting simulation, System Dynamics

Helofytenfilter niet geschikt voor nazuivering mestvloeistof

Uit literatuuronderzoek blijkt dat de goedkope waterzuiveringstechniek van het helofyten- of plantenfilter onvoldoende perspectief biedt voor het verder zuiveren van dit condenswater

Air Treatment Techniques for Abatement of Emissions from Intensive Livestock Production

Intensive livestock production is connected with a number of environmental effects, including emissions of ammonia (NH3), greenhouse gases (CH4 and N2O), odour, and particulate matter (PM10 and PM2.5). Possible strategies for emission reduction include feed management, adaptation of housing design, and, in case of mechanically ventilated animal houses, the application of end-of-pipe air treatment, viz acid scrubbers and bioscrubbers. Air treatment techniques can achieve very high emission reductions (up to 100% ammonia removal for acid scrubbers). Furthermore, air treatment offers the possibility to achieve removal of not just one compound but of a combined removal of a variety of pollutants (ammonia, odour and particulate matter) at the same time. The successful application of scrubbers is of increasing importance as intensive livestock operations have to comply with ever stricter regulations and emission limits. Research is needed to address topics such as reduction of costs (both investment and operational costs), improvement of process control to guarantee stable removal efficiencies, decrease of N2O production in bioscrubbers, and increase of odour removal efficienc

Air scrubbing techniques for the reduction of gaseous emissions from livestock farms. Actual knowledge in the Netherlands and possibilities for implementation on Spanish farms.

In The Netherlands, packed-bed biotrickling filters and acid scrubbers for removal of ammonia from exhaust air of animal houses are off-the-shelf techniques for ammonia removal. At the moment a new generation of so-called "multi-pollutant scrubbers" is being developed and tested that also removes odour and particulate matter from the air. Air cleaning systems are unusual in Spanish farms. The study of these techniques and their adaptation to Spanish farms, can be an interesting issue in order to achieve the national gas emission reduction commitments, and also to reduce social nuisances

Elektronische monitoring van luchtwassers op veehouderijbedrijven = Automated process monitoring and data logging of air scrubbers at animal houses

At 6 animal houses air scrubbers equipped with an automated process monitoring and data logging system were tested. The measured values were successfully stored but the measured values, especially the pH and EC of the recirculation water, appeared not to be correct at all times

Deskstudie naar de potentiële verlaging van de methaanemissie bij het comfort slat mats systeem en het balansballen systeem voor rundveestallen = Desk study regarding the lowered methane emission from animal houses using either the comfort slat mat or balance ball system for cattle houses

Research on the comfort slat mats and the balance ball system for cattle houses showed an emission reduction of methane. Additional research is necessary to be able to conclusively explain this

Afvoer en scheiding van strorijke kraamzeugenmest met vijzelsysteem

Het doel van het onderzoek is het uittesten van een vijzelsysteem voor afvoer en scheiding van strorijke mest uit drie biologische kraamafdelingen met elk drie hokken (gedeeltelijk roostervloer)

Haalbaarheidsstudie terugwinning van mestnutriënten : Fase 1: Processchema en nutriëntenstromen = Feasibility study on nutrient recovery from animal manure : Phase 1: Process scheme and nutrient flows

A process scheme for a new manure treatment system for pig and cattle manure was formulated which aims to produce manure nutrient flows with added value. The basic process behind the treatment system is fermentation of manure, which is preceded by both stripping ammonia and chemical digestion of the organic solids. The fermented manure is separated in a thin and a thick phase, which is further treated

Alternatieven voor zwavelzuur in chemische luchtwassers = Alternatives for the use of sulphuric acid in air scrubbers

This report provides an overview of the acids that can be used in air scrubbers for ammonia removal, including organic acids, in stables. Emphasis is put on safety, efficiency and cost of the acids