Search results for "multiple"
showing 10 items of 2678 documents
smatr 3 - an R package for estimation and inference about allometric lines
2011
Summary 1. The Standardised Major Axis Tests and Routines (SMATR) software provides tools for estimation and inference about allometric lines, currently widely used in ecology and evolution. 2. This paper describes some significant improvements to the functionality of the package, now available on R in smatr version 3. 3. New inclusions in the package include sma and ma functions that accept formula input and perform the key inference tasks; multiple comparisons; graphical methods for visualising data and checking (S)MA assumptions; robust (S)MA estimation and inference tools.
Sample details on OSL data for aeolian sediments in north-eastern part of European Sand Belt
2019
A compilation of previously published and unpublished absolute age (OSL and TL) determinations of aeolian sediments from the north-eastern part of European Sand Belt. Contains age, error, sampling depth, location etc. and a reference to data source. Coordinates of sampling locations for contemporary publications are taken from field observations (GPS), but older ones - published schematic maps. Data set is created according to schema of DATED-1 database (https://doi.org/10.1594/PANGAEA.848117).
Correlation between HHV-6 reactivation and multiple sclerosis disease activity.
2002
This study examined the association between HHV-6 infection and multiple sclerosis (MS) and the relationship between HHV-6 reactivation and disease activity. The frequency of HHV-6 genomic sequences in peripheral blood mononuclear cells (PBMCs), the incidence of plasma viremia (nPCR), the transcription of viral mRNA in PBMCs (RT-PCR), the presence of antiviral IgM and IgG class antibodies in the plasma (IFA) of 16 relapsing/remitting and secondary progressive MS patients were studied in comparison with clinical manifestations of the disease, magnetic resonance imaging (MRI) of brain, and serum interleukin (IL)-12 concentrations (ELISA). The prevalence of HHV-6 infection was significantly hi…
SETUP OF VIRTUAL EXPERIMENTS AND CRITICAL ANALYSIS OF CONVENTIONAL THERMOECONOMIC DIAGNOSIS OF MULTIPLE FAULTS IN AIR-CONDENSED ROOFTOP SYSTEMS
2012
The diagnosis of soft faults in vapor compression cooling systems is a crucial activity, since malfunctions may provoke heavy degradation in plant performance and increase the power consumption for space cooling. Among the various Faults Detection and Diagnosis techniques developed over the last two decades, thermoeconomic diagnosis has been playing only a marginal role due to the difficulties encountered when applying the conventional thermoeconomic approaches to vapor compression refrigeration plants. In this paper a critical analysis on capabilities and limits of thermoeconomic diagnosis of refrigeration systems is proposed. The reference plant assumed for this study is a 116 kWc air-con…
Application of advanced thermodynamics, thermoeconomics and exergy costing to a Multiple Effect Distillation plant: In-depth analysis of cost formati…
2015
Abstract The high thermal energy consumption per m3 fresh water is one of the main barriers to the spread of thermally driven desalination processes and has limited their use to applications in countries with high reserves of fossil fuels or to specific technological solutions like dual purpose cogeneration plants and solar desalination systems. Being energy conversion efficiency a major issue to improve the performance of thermally driven desalination plants, thermoeconomic analysis has been attracting the efforts of researchers for the identification of margins for process improvement. In this paper a rigorous exergy and thermoeconomic analysis is presented for an 8 effect forward feed Mu…
Thermoeconomic optimization of a renewable polygeneration system serving a small isolated community
2015
During the last years, special attention has been paid to renewable polygeneration technologies, able of simultaneously producing thermal, cooling, electrical energy and desalinated water from seawater. This paper focuses on an innovative polygeneration system driven by renewable energy sources, including the following technologies: hybrid photovoltaic/thermal collectors, concentrating parabolic trough (CPVT), a biomass heater, a single-stage absorption chiller and a multiple-effect distillation desalination system. The system is designed to cover the base load of an isolated small community. In previous papers, the dynamic simulation model about plant operation is discussed. In this paper,…
Exergetic and exergoeconomic analysis of a renewable polygeneration system and viability study for small isolated communities
2015
Abstract A great interest has recently arisen for the sustainable supply of energy and fresh water, due to the growing demand from developing countries. Facing this demand by traditional technologies implies evident risks related with the high cost of fossil fuels and their environmental impact. Then, alternative solutions based on the use of renewable sources and innovative technologies must be considered. In this paper a renewable polygeneration system is examined, which includes a solar field based on parabolic trough photovoltaic/thermal collectors, a biomass heater, an absorption chiller and a Multiple Effect Distillation desalination unit. Plant operation under dynamic conditions has …
Exergy analysis and thermoeconomic cost accounting of a Combined Heat and Power steam cycle integrated with a Multi Effect Distillation-Thermal Vapou…
2017
Abstract In this paper an exergy analysis and thermoeconomic cost accounting of a Combined Heat and Power steam cycle integrated with Multi Effect Distillation-Thermal Vapour Compression plant is performed; the goal of the study is to show how these methodologies provide a rational criterion to allocate production costs on electricity and freshwater in such a dual purpose system. After a brief overview on the methodology and a description of reference plant, exergy analysis is carried out to calculate exergy flows and exergy efficiencies at component level. A detailed description of the adopted thermoeconomic model is given. In a first scenario, cost accounting is performed assuming that th…
Reverse electrodialysis heat engine with multi-effect distillation: Exergy analysis and perspectives
2019
Abstract The increasing worldwide energy demand is rising the interest on alternative power production technologies based on renewable and emission-free energy sources. In this regard, the closed-loop reverse electrodialysis heat engine is a promising technology with the potential to convert low-grade heat into electric power. The reverse electrodialysis technology has been under investigation in the last years to explore the real potentials for energy generation from natural and artificial solutions, and recent works have been addressing also the potential of its coupling with regeneration strategies, looking at medium and large energy supply purposes. In this work, for the first time, a c…
Thermodynamic, Exergy, and Thermoeconomic analysis of Multiple Effect Distillation Processes
2018
Abstract Multiple effect distillation (MED) is nowadays the preferred technology for the construction of new plants based on thermal processes in the growing desalination market. MED technology, in fact, presents a number of advantages with respect to the more traditional multistage flash technology, among all the lower energy consumption achievable in MED plants. However, a large potential for improvement in terms of lowering production costs still exists, which stimulates further efforts on process optimization from companies and researchers involved in the field. Thermodynamic and exergy analysis provides useful insights regarding the identification of main inefficiencies and the margins…