12,432 research outputs found
Performance of the Lester battery charger in electric vehicles
Tests are performed on an improved battery charger. The primary purpose of the testing is to develop test methodologies for battery charger evaluation. Tests are developed to characterize the charger in terms of its charge algorithm and to assess the effects of battery initial state of charge and temperature on charger and battery efficiency. Tests show this charger to be a considerable improvement in the state of the art for electric vehicle chargers
The significance of organic carbon and nutrient export from peatland-dominated landscapes subject to disturbance, a stoichiometric perspective
The terrestrial-aquatic interface is a crucial environment in which to consider the fate of exported terrestrial carbon in the aquatic system. Here the fate of dissolved organic carbon (DOC) may be controlled by nutrient availability. However, peat-dominated headwater catchments are normally of low nutrient status and thus there is little data on how DOC and nutrient export co-varies. We present nutrient and DOC data for two UK catchments dominated by peat headwaters. One, Whitelee, is undergoing development for Europe's largest windfarm. Glen Dye by comparison is relatively undisturbed. At both sites there are significant linear relationships between DOC and soluble reactive phosphorus and nitrate concentrations in the drainage waters. However, inter-catchment differences exist. Changes in the pattern of nutrient and carbon export at Whitelee reveal that landscape disturbance associated with windfarm development impacts the receiving waters, and that nutrient export does not increase in a stoichiometric manner that will promote increase in microbial biomass but rather supports aquatic respiration. In turn greater CO2 efflux may prevail. Hence disturbance of terrestrial carbon stores may impact the both the aquatic and gaseous carbon cycle. We suggest estimates of aquatic carbon export should inform the decision-making process prior to development in ecosystems and catchments with high terrestrial carbon storage
Skolem-type difference sets for cycle systems
Cyclic m-cycle systems of order v are constructed for all m greater than or equal to 3, and all v = 1(mod 2m). This result has been settled previously by several authors. In this paper, we provide a different solution, as a consequence of a more general result, which handles all cases using similar methods and which also allows us to prove necessary and sufficient conditions for the existence of a cyclic m-cycle system of K-v - F for all m greater than or equal to 3, and all v = 2(mod 2m)
Prolonging the Cut of Southern Pine Part I. Possibilities of a Second Cut; Part II. Close Utilization of Timber
Part I - Since 1907 the Yale Forest School has conducted the field workand instruction of the Senior class in the spring term in coopera-tion with lumber companies located in the southern states. Thecompanies which have extended this cooperation are:1907, Missouri Lumber and Mining Co., Grandin, Missouri.1908, Kaul Lumber Co., Hollins, Alabama.1909, Thompson Brothers Lumber Co., Doucette, Texas.1910, Louisiana Central Lumber Co., Clarks, Louisiana.1911, Thompson Brothers Lumber Co., Trinity, Texas.191~, Crossett Lumber Co., Crossett, Arkansas.
Part II - The lack of close utilization of yellow pine timber is apparenton many operations in the South. In the following discussionsome of the more common wastes are considered and a methodsuggested whereby lumbermen may prolong the life of their opera-tions. The data were secured during the years 1907-1~ in ~Iis‐souri, Alabama, Louisiana, Texas and Arkansas. The need forthe exercise of more care in felling and log making was distinctlyshown in the discussion which followed the writer\u27s presentation ofthis subject before the Southern Logging Association during itsannual meeting in September, 191~.
1913, Southern Lumber Co., Warren, Arkansas
Z2SAL: a translation-based model checker for Z
Despite being widely known and accepted in industry, the Z formal specification language has not so far been well supported by automated verification tools, mostly because of the challenges in handling the abstraction of the language. In this paper we discuss a novel approach to building a model-checker for Z, which involves implementing a translation from Z into SAL, the input language for the Symbolic Analysis Laboratory, a toolset which includes a number of model-checkers and a simulator. The Z2SAL translation deals with a number of important issues, including: mapping unbounded, abstract specifications into bounded, finite models amenable to a BDD-based symbolic checker; converting a non-constructive and piecemeal style of functional specification into a deterministic, automaton-based style of specification; and supporting the rich set-based vocabulary of the Z mathematical toolkit. This paper discusses progress made towards implementing as complete and faithful a translation as possible, while highlighting certain assumptions, respecting certain limitations and making use of available optimisations. The translation is illustrated throughout with examples; and a complete working example is presented, together with performance data
Defying jet-gas alignment in two radio galaxies at z~2 with extended light profiles: Similarities to brightest cluster galaxies
We report the detection of extended warm ionized gas in two powerful
high-redshift radio galaxies, NVSS J210626-314003 at z=2.10 and TXS 2353-003 at
z=1.49, that does not appear to be associated with the radio jets. This is
contrary to what would be expected from the alignment effect, a characteristic
feature of distant, powerful radio galaxies at z> 0.6. The gas also has smaller
velocity gradients and line widths than most other high-z radio galaxies with
similar data. Both galaxies are part of a systematic study of 50 high-redshift
radio galaxies with SINFONI, and are the only two that are characterized by the
presence of high surface-brightness gas not associated with the jet axis and by
the absence of such gas aligned with the jet. Both galaxies are spatially
resolved with ISAAC broadband imaging covering the rest-frame R band, and have
extended wings that cannot be attributed to line contamination. We argue that
the gas and stellar properties of these galaxies are more akin to gas-rich
brightest cluster galaxies in cool-core clusters than the general population of
high-redshift radio galaxies at z>2. In support of this interpretation, one of
our sources, TXS 2353-003, for which we have H\alpha\ narrowband imaging, is
associated with an overdensity of candidate H\alpha\ emitters by a factor of 8
relative to the field at z=1.5. We discuss possible scenarios of the
evolutionary state of these galaxies and the nature of their emission line gas
within the context of cyclical AGN feedback.Comment: A&A in pres
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