50 research outputs found
Proposing a life cycle land use impact calculation methodology
The Life Cycle Assessment (LCA) community is yet to come to a consensus on a methodology to incorporate land use in LCA, still struggling with what exactly should be assessed and which indicators should be used. To solve this problem we start from concepts and models describing how ecosystems function and sustain, in order to understand how land use affects them. Earlier our research group presented a methodology based on the ecosystem exergy concept. This concept as based on the hypothesis that ecosystems develop towards more effective degradation of exergy fluxes passing through the system and is derived from two axioms: the principles of (i) maximum exergy storage and the (ii) maximum exergy dissipation. This concept aiming at the area of protection natural environment is different from conventional exergy analysis in LCA focusing on natural resources. To prevent confusion, the ecosystem exergy concept is further referred to as the MAximum Storage and Dissipation concept (MASD concept). In this paper we present how this concept identifies end-point impacts, mid-point impacts and mid-point indicators. The identified end-point impacts to assess are Ecosystem Structural Quality (ESQ) and Ecosystem Functional Quality (EFQ). In order to quantify these end-point impacts a dynamic multi-indicator set is proposed for quantifying the mid-point impacts on soil fertility, biodiversity and biomass production (quantifying the ESQ) and soil structure, vegetation structure and on-site water balance (quantifying the EFQ). Further we present an impact calculation method suitable for different environmental assessment tools and demonstrate the incorporation of the methodology in LCA
Proposing a life cycle land use impact calculation methodology
The Life Cycle Assessment (LCA) community is yet to come to a consensus on a methodology to incorporate land use in LCA. Earlier our research group presented a methodology based on the ecosystem exergy concept. The ecosystem exergy concept suggests that ecosystems develop towards more effective degradation of energy fluxes passing through the system. The concept is argued to be derivable from two axioms: the principles of (i) maximum exergy storage and the (ii) maximum exergy dissipation. In this paper we present a methodology to assess impacts of human induced land use occupation, in which we make a difference between functional and structural land use impacts. The methodology follows a dynamic multi-indicator approach looking at mid-point impacts on soil fertility, soil structure, biomass production, vegetation structure, on-site water balance and biodiversity. The impact scores are calculated as a relative difference with a reference system. We propose to calculate the impact by calculating the land quality change between the former and the actual land use relative to the quality of the potential natural vegetation. Impact scores are then aggregated, as endpoint impacts, in (i) structural land use impact (exergy storage capacity) and (ii) functional land use impact (exergy dissipation capacity). For aggregation of the relative mid-point impact scores no characterization factor is used. In order to fit this impact calculation in the LCA framework the end-point impact scores are multiplied by a LCA component, a component that enables us to report the impact per functional unit
Mental Rotation Meets the Motion Aftereffect: The Role of hV5/MT+ in Visual Mental Imagery
Uniqueness Typing for Resource Management in Message-Passing Concurrency
We view channels as the main form of resources in a message-passing
programming paradigm. These channels need to be carefully managed in settings
where resources are scarce. To study this problem, we extend the pi-calculus
with primitives for channel allocation and deallocation and allow channels to
be reused to communicate values of different types. Inevitably, the added
expressiveness increases the possibilities for runtime errors. We define a
substructural type system which combines uniqueness typing and affine typing to
reject these ill-behaved programs
Life cycle cost assessment of insect based feed production in West Africa
While there is a growing body of research investigating the technical feasibility and nutritional properties of insect based feeds (IBFs), thus far little attention has been devoted to gauge the economic implications of implementation. This study has investigated the economic performance of ex-ante modelled IBF production systems operating in the geographical context of West Africa. A Life Cycle Cost (LCC) analysis of recently published life cycle inventory (LCI) data served as a basis to analyse and compare the economic performances of IBF production systems using Musca domestica and Hermetia illucens reared on different substrates. To gauge the application potential of IBF in West Africa, estimated breakeven sale prices of IBFs were benchmarked against the customary market prices of conventional feeds. The results show that the economic performance of IBF production in West Africa is largely determined by the costs attributed to labour and the procurement of rearing substrates, attesting economic advantages to the production of M. domestica larvae by measure of breakeven price (1.28–1.74 EUR/kg IBF) and LCC (1.72–1.99 EUR/kg IBF). A comparison of the breakeven sale prices of IBF with market prices of conventional feeds suggest that IBF has potential to substitute imported fishmeal, but findings offer no support for conjectured economic advantages over plant based feeds
High Resolution MEMS Accelerometers to Estimate VO2 and Compare Running Mechanics between Highly Trained Inter-Collegiate and Untrained Runners
BACKGROUND: The purposes of this study were to determine the validity and reliability of high resolution accelerometers (HRA) relative to VO(2) and speed, and compare putative differences in HRA signal between trained (T) and untrained (UT) runners during treadmill locomotion. METHODOLOGY: Runners performed 2 incremental VO(2max) trials while wearing HRA. RMS of high frequency signal from three axes (VT, ML, AP) and the Euclidean resultant (RES) were compared to VO(2) to determine validity and reliability. Additionally, axial rms relative to speed, and ratio of axial accelerations to RES were compared between T and UT to determine if differences in running mechanics could be identified between the two groups. PRINCIPAL FINDINGS: Regression of RES was strongly related to VO(2), but T was different than UT (r = 0.96 vs 0.92; p<.001) for walking and running. During walking, only the ratio of ML and AP to RES were different between groups. For running, nearly all acceleration parameters were lower for T than UT, the exception being ratio of VT to RES, which was higher in T than UT. All of these differences during running were despite higher VO(2), O(2) cost, and lower RER in T vs UT, which resulted in no significant difference in energy expenditure between groups. CONCLUSIONS/SIGNFICANCE: These results indicate that HRA can accurately and reliably estimate VO(2) during treadmill locomotion, but differences exist between T and UT that should be considered when estimating energy expenditure. Differences in running mechanics between T and UT were identified, yet the importance of these differences remains to be determined
Proposing a life cycle land use impact calculation methodology
The Life Cycle Assessment (LCA) community is yet to come to a consensus on a methodology to incorporate land use in LCA, still struggling with what exactly should be assessed and which indicators should be used. To solve this problem we start from concepts and models describing how ecosystems function and sustain, in order to understand how land use affects them. Earlier our research group presented a methodology based on the ecosystem exergy concept. This concept as based on the hypothesis that ecosystems develop towards more effective degradation of exergy fluxes passing through the system and is derived from two axioms: the principles of (i) maximum exergy storage and the (ii) maximum exergy dissipation. This concept aiming at the area of protection natural environment is different from conventional exergy analysis in LCA focusing on natural resources. To prevent confusion, the ecosystem exergy concept is further referred to as the MAximum Storage and Dissipation concept (MASD concept). In this paper we present how this concept identifies end-point impacts, mid-point impacts and mid-point indicators. The identified end-point impacts to assess are Ecosystem Structural Quality (ESQ) and Ecosystem Functional Quality (EFQ). In order to quantify these end-point impacts a dynamic multi-indicator set is proposed for quantifying the mid-point impacts on soil fertility, biodiversity and biomass production (quantifying the ESQ) and soil structure, vegetation structure and on-site water balance (quantifying the EFQ). Further we present an impact calculation method suitable for different environmental assessment tools and demonstrate the incorporation of the methodology in LCA.status: publishe
Phosphorus and energy flows through the food system of Brussels Capital Region
info:eu-repo/semantics/publishe
Towards circular urban food systems – phosphorus and energy flows in Brussels Capital Region
info:eu-repo/semantics/publishe
Phosphorus and energy flows through the food system of Brussels Capital Region
Urban food systems are linear and wasteful. Strategies towards more circular food systems need to be adopted; however, what these strategies may be and what effects they may have on other urban systems is not well documented. With this study, we offer a systemic representation of the Brussels Capital Region food system through mapping its phosphorus and energy flows, and we evaluate the effect that three theoretical scenarios will have on these flows, and on the circularity level of the system. The results show that the Brussels food system is strongly linear and that no more than 2% of the incoming P can currently be reused within the city. Food waste valorization and sewage sludge utilization can increase the amount of P available for reuse without negatively affecting the net amount of electricity recovered. The amount of P available in the urban effluents can theoretically cover the demand for mineral P in the agricultural systems of the two neighboring Brabant provinces. The regulatory framework for the reuse of urban effluents is, however, hostile and it is still to be determined whether there is a demand for re-introducing these P flows in the agri-food system that feeds Brussels.status: Published onlin