3,196 research outputs found
The effect of dietary n-3 HUFA levels and DHA/EPA ratios on growth, survival and osmotic stress tolerance of Chinese mitten crab <i>Eriocheir sinensis</i> larvae
The effect of varying levels of dietary n-3 highly unsaturated fatty acid (HUFA) and docosahexaenoic acid/eicosapentaenoic acid (DHA/EPA) ratios on growth, survival and osmotic stress tolerance of Eriocheir sinensis zoea larvae was studied in two separate experiments. In experiment I, larvae were fed rotifers and Artemia enriched with ICES emulsions with 0, 30 and 50% total n-3 HUFA levels but with the same DHA/EPA ratio of 0.6. In experiment II, larvae were fed different combinations of enriched rotifers and Artemia, in which, rotifers were enriched with emulsions containing 30% total n-3 HUFA, but different DHA/EPA ratio of 0.6, 2 and 4; while Artemia were enriched with the same emulsions, but DHA/EPA ratio of 0.6 and 4. In both experiments, un-enriched rotifers cultured on baker's yeast and newly-hatched Artemia nauplii were used as control diets. Larvae were fed rotifers at zoea 1 and zoea 2 stages; upon reaching zoea 3 stage, Artemia was introduced.Experiment I revealed no significant effect of prey enrichment on the survival of megalopa among treatments, but higher total n-3 HUFA levels significantly enhanced larval development (larval stage index, LSI) and resulted in higher individual dry body weight of megalopa. Furthermore higher dietary n-3 HUFA levels also resulted in better tolerance to salinity stress. Experiment II indicated that at the same total n-3 HUFA level, larvae continuously receiving a low dietary DHA/EPA ratio had significantly lower survival at the megalopa stage and inferior individual body weight at the megalopa stage, but no negative effect was observed on larval development (LSI). The ability to endure salinity stress of zoea 3, zoea 5 and megalopa fed diets with higher DHA/EPA ratio was also improved
A novel five-phase fault-tolerant modular in-wheel permanent-magnet synchronous machine for electric vehicles
© 2015 AIP Publishing LLC. This paper describes a five-phase fault-tolerant modular in-wheel permanent-magnet synchronous machine (PMSM) for electric vehicles. By adopting both the analytical and finite-element methods, the magnetic isolation abilities of some typical slot/pole combinations are analyzed, and a new fractional-slot concentrated winding topology that features hybrid single/double-layer concentrated windings and modular stator structure is developed. For the proposed hybrid single/double-layer concentrated windings, feasible slot/pole combinations are studied for three-, four-, and five-phase PMSMs. A five-phase in-wheel PMSM that adopts the proposed winding topology is designed and compared with the conventional PMSM, and the proposed machine shows advantages of large output torque, zero mutual inductances, low short-circuit current, and high magnetic isolation ability. Some of the analysis results are verified by experiments
Accelerating dynamic data race detection using static thread interference analysis
Copyright © 2016 ACM. Precise dynamic race detectors report an error if and only if more than one thread concurrently exhibits conict on a memory access. They insert instrumentations at compiletime to perform runtime checks on all memory accesses to ensure that all races are captured and no spurious warnings are generated. However, a dynamic race check for a particular memory access statement is guaranteed to be redundant if the statement can be statically identified as thread interference-free. Despite significant recent advances in dynamic detection techniques, the redundant check remains a critical factor that leads to prohibitive overhead of dynamic race detection for multithreaded programs. In this paper, we present a new framework that eliminates redundant race check and boosts the dynamic race detection by performing static optimizations on top of a series of thread interference analysis phases. Our framework is implemented on top of LLVM 3.5.0 and evaluated with an industry dynamic race detector TSAN which is available as a part of LLVM tool chain. 11 benchmarks from SPLASH2 are used to evaluate the effectiveness of our approach in accelerating TSAN by eliminating redundant interference-free checks. The experimental result demonstrates our new approach achieves from 1.4x to 4.0x (2.4x on average) speedup over original TSAN under 4 threads setting, and achieves from 1.3x to 4.6x (2.6x on average) speedup under 16 threads setting
Quenched QCD with domain wall fermions
We report on simulations of quenched QCD using domain wall fermions, where we
focus on basic questions about the formalism and its ability to produce
expected low energy hadronic physics for light quarks. The work reported here
is on quenched lattices at and 5.85, using values
for the length of the fifth dimension between 10 and 48. We report results for
parameter choices which lead to the desired number of flavors, a study of
undamped modes in the extra dimension and hadron masses.Comment: Contribution to Lattice '98. Presented by R. Mawhinney. 3 pages, 3
figure
Dynamical QCD thermodynamics with domain wall fermions
We present results from numerical simulations of full, two flavor QCD
thermodynamics at N_t=4 with domain wall fermions. For the first time a
numerical simulation of the full QCD phase transition displays a low
temperature phase with spontaneous chiral symmetry breaking but intact flavor
symmetry and a high temperature phase with the full SU(2) x SU(2) chiral flavor
symmetry.Comment: LATTICE98(hightemp
The domain wall fermion chiral condensate in quenched QCD
We examine the chiral limit of domain wall fermions in quenched QCD. One
expects that in a quenched simulation, exact fermion zero modes will give a
divergent, 1/m behavior in the chiral condensate for sufficiently small valence
quark masses. Unlike other fermion formulations, domain wall fermions clearly
demonstrate this behavior.Comment: LATTICE98(spectrum), G. R. Fleming presented talk, 5 pages, 3
figures, corrected typos in printed versio
Optimization Design on Ventilation Openings of Super Large Circular Coal Storage Dome
In order to reduce the pollution of the atmospheric environment, the super large coal storage warehouse has gradually become the main coal storage mode of power plants and other enterprises. However, due to the enclosed structural form, volatile coal dust and coal seam volatile combustible gas concentration is too high, which resulting in increased risk of ignition detonation. Therefore, this paper based on ventilation engineering theory and combined with CFD which focus on natural ventilation used in large diameter (D = 100 m) circular coal storage dome. The impact of opening modes, opening positions and opening size of super large circular coal storage dome on ventilated characteristics were also studied. The designed method of ventilated openings for super large circular coal storage dome is further proposed
Illustrating a new global-scale approach to estimating potential reduction in fish species richness due to flow alteration
Changes in river discharge due to human activities and climate change would
affect the sustainability of freshwater ecosystems. To globally assess how
changes in river discharge will affect the future status of freshwater
ecosystems, global-scale hydrological simulations need to be connected with
a model to estimate the durability of freshwater ecosystems. However, the
development of this specific modelling combination for the global scale is
still in its infancy. In this study, two statistical methods are introduced
to link flow regimes to fish species richness (FSR): one is based on a
linear relationship between FSR and mean river discharge (hereafter, FSR-MAD
method), and the other is based on a multi-linear relationship between FSR
and ecologically relevant flow indices involving several other flow
characteristics and mean river discharge (FSR-FLVAR method). The FSR-MAD
method has been used previously in global simulation studies. The FSR-FLVAR
method is newly introduced here. These statistical methods for estimating
FSR were combined with a set of global river discharge simulations to
evaluate the potential impact of climate-change-induced flow alterations on
FSR changes. Generally, future reductions in FSR with the FSR-FLVAR method
are greater and much more scattered than with the FSR-MAD method. In arid
regions, both methods indicate reductions in FSR because mean discharge is
projected to decrease from past to future, although the magnitude of
reductions in FSR is different between the two methods. In contrast, in
heavy-snow regions a large reduction in FSR is shown by the FSR-FLVAR method
due to increases in the frequency of low and high flows. Although further
research is clearly needed to conclude which method is more appropriate,
this study demonstrates that the FSR-FLVAR method could produce considerably
different results when assessing the global role of flow alterations in
changing freshwater ecosystems
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