Search results for " spread"
showing 10 items of 241 documents
A virtual spreader to overcome experimental limits: Example of use to deepen the meaning of the transverse coefficient of variation
2017
International audience; A virtual spreader was modelled by combining the use of theoretical motion equations and statistical distributions of input parameters. These parameters were deduced from experimental measurements using a custom-made spreader, an imaging system, a particle impact recording device and a rotating test bench. Using this model, each spread pattern was computed using a random selection of values following the statistical distribution of each input parameter. Using simulations, we quantified how the CV value was affected by application rates and measurement protocols whatever spreader settings. Simulations showed the CV value and its measurement variability increased when …
Economies d'agglomération et configurations spatiales dans les espaces ruraux
1997
The question to be addressed here is that of the agglomeration/dispersion forces that are likely to account for the location of people and jobs in rural areas and the way they explain spatial patterns in rural areas depending on urban influence. Economic geography models may provide suitable tools with which to investigate the organization of rural areas. We first review these models, focusing on dispersion forces, which rest basically on land consumption and transport costs. We suggest then a set of hypotheses concerning the main forces at work in rural areas. Intensity of agglomeration economies is hypothesized to be related to the urban size, which in turn induces increasing land rents a…
Fouille d’un quartier funéraire des Ier et IIe s. dans le suburbium de Soissons/Augusta Suessionum : aires de crémation et inhumations d’enfants
2012
In the beginning of 2008 a preventive excavation has been conducted on about 1200 m2 of a large antique cemetery situated upon the butte Saint-Jean at Soissons (Aisne). In this cemetery, almost unknown, located south-west of the Roman town Augusta Suessionum a consistent activity in the part being excavated took place between the Augustan era and mid 2nd c. The total number of inhumations uncovered is 186 (mainly of infants). Cremations were executed from the very beginning altogether with inhumations, in more or less close proximity to them according to periods, then became predominant to the detriment of burials which were just previously arranged. Different structures clearly connected t…
Simulation of granular organic fertilizer application by centrifugal spreader
2021
There is no specialized equipment designed to spread granular cylindrical organic fertilizer in the soil. There are also no rational recommendations available on how to spread this type of fertilizer. Mineral fertilizer spreaders are most often used for spreading granulated organic fertilizer. However, these fertilizers are significantly different from mineral fertilizers. Due to these differences, organic granular fertilizers often are spread unevenly, and the fertilizer does not reach the required working width. Furthermore, the rate of spreading is not accurate, and the fertilizer is often crushed too much. The objective of this research is to develop a simulation model for granular orga…
Comparative sclerochronology of modern and mid-Pliocene (c. 3.5Ma) Aequipecten opercularis (Mollusca, Bivalvia): an insight into past and future clim…
2009
Records of environment contained within the accretionarily deposited tissues of fossil organisms afford a means of detailed reconstruction of past climates and hence of rigorous testing of numerical climate models. We identify the environmental factors controlling oxygen and carbon stable-isotopic composition, and microgrowth-increment size, in the shell of modern examples of the Queen Scallop, Aequipecten opercularis. This understanding is then applied in interpretation of data from mid-Pliocene A. opercularis from eastern England. On the basis of oxygen-isotope evidence we conclude that winter minimum seafloor temperature was similar to present values (typically 6–7 °C) in the adjacent so…
Hedging spark spread risk with futures
2018
Abstract This paper discusses the spark spread risk management using electricity and natural gas futures. We focus on three European markets in which the natural gas share in the fuel mix varies considerably: Germany, the United Kingdom, and the Netherlands. We find that spark spread returns are partially predictable, and consequently, the Ederington and Salas (2008) minimum variance hedging approach should be applied. Hedging the spark spread is more difficult than hedging electricity and natural gas price risks with individual futures contracts. Whereas spark spread risk reduction for monthly periods produces values of between 20.05% and 48.90%, electricity and natural gas individual hedg…
Spreading Depression Induces Permanent Cell Swelling Under Penumbra Conditions
2000
Background. Spreading depression (SD) is known to go along with temporary breakdown of ion gradients and cell swelling which spontaneously normalizes. Here, the effects of SD at reduced flow conditions as encountered in the ischemic penumbra are examined.
Causalities between CO2, electricity, and other energy variables during phase I and phase II of the EU ETS
2010
The topic of this article is the analysis of the interplay between daily carbon, electricity and gas price data with the European Union Emission Trading System (EU ETS) for CO2 emissions. In a first step we have performed Granger causality tests for Phase I of the EU ETS (January 2005 until December 2007) and the first year of Phase II of the EU ETS (2008). The analysis includes both spot and forward markets—given the close interactions between the two sets of markets. The results show that during Phase I coal and gas prices, through the clean dark and spark spread, impacted CO2 futures prices, which in return Granger caused electricity prices. During the first year of the Phase II, the sho…
Glutamate Enhances Brain Damage from Ischemia and Trauma
1997
The amino acid glutamate is a model agent to demonstrate the significance of neurotoxic mediator compounds in secondary brain damage from trauma, ischemia or other adverse conditions. Intensive research of the role of mediator compounds is clinically worthwile as more specific forms of treatment may emerge for the benefit of afflicted patients. In view of the great number of factors, cytokines, etc., which could play a role, it is mandatory that a mediator function in secondary brain damage is identified according to the stringent requirements established for that purpose. Glutamate has been shown — as is the case for only a few other agents — to meet all the criteria of a mediator of secon…
Sport and Quality of Life
2022
Negli ultimi trent’anni lo sport ha assunto un significato molto rilevante nella vita delle persone e, seppure con notevoli differenze, sia nei paesi a sviluppo economico avanzato, sia in quelli in via di sviluppo. A livello individuale, esso ha costituito un’area di investimento identitario quando ha assunto la forma di sport spettacolo del quale fruire, alimentando la pratica del tifo e il fandom o costituendo il modello di uno stile di vita vincente; ma anche quando ha assunto la forma di pratica del tempo libero attraverso la quale tenersi in forma, facendo crescere, in questo caso, la diffusione di una cultura della salute e del benessere. Si tratta di due modalità di approcciare al co…