764 research outputs found
Singular del Pezzo surfaces over finite fields
If is a singular del Pezzo surface of degree over a finite field
with only rational double point singularities, does there
always exist a smooth -point on ? We show that this is true
for and give counterexamples in the case of
Assessment on performance and variability in different sweet orange (Citrus sinensis Obseck) cultivars under Punjab conditions
Based on morphological characterization, the performance of eighteen sweet orange, (Citrus sinensis Obseck) cultivars were evaluated. On the basis of two year data, the maximum mean fruit weight (316.25 gm) was recorded in Moro, while the maximum mean fruit diameter and mean fruit length was recorded in Mosambi and Olinda Valencia (87.32 mm and 81.33 mm, respectively). Albedo thickness was recorded maximum in Ruby Nucellar (3.42 mm). Highest total soluble solids was recorded in cultivar Moro (11.450 brix), while the titratable acidity was recorded maximum in Valencia Calizonida (1.21 %). Fruit axis diameter and Fruit rind thickness were recorded maximum in Rhode Red Valencia and Vernia (15.12 mm and 8.11 mm, respectively). In the variability studies, the maximum genotypic coefficient of variance (GCV) and phenotypic coefficient of variance (PCV) was recorded maximum for titratable acidity (27.88 and 27.94, respectively) followed by albedo thickness (23.77 and 23.78, respectively) and fruit weight (21.52 and 21.67, respectively). Genetic advance per cent of mean was recorded for titratable acidity (57.31%) followed by albedo thickness (48.96 %) and fruit weight (44.03 %) suggesting that further selection will be effective for improvement in these traits
Smart integrated adaptive centralized controller for islanded microgrids under minimized load shedding
In this paper, a smart integrated adaptive centralized controller is proposed for monitoring and controlling integrated renewable energy sources (RESs), both for intentional and unintentional islanding modes of operation for microgrids, as well as, for a variable range of transient load shedding and fault scenarios corresponding to electrical power system outages. It is demonstrated that the proposed smart adaptive controller is capable of instructing fast frequency response by proper coordination of the dispatch of RESs units such as, mini-hydro, Photovoltaic (PV), Battery Energy Storage System (BESS) and standby diesel generators. In particular, the BESS used as power reserve, at the early stage of fault events can prevent detrimental and uncontrollable system frequency decline and the extent of load shedding. In summary, the performance of a centralized controller in terms of a fast frequency response recovery feature is validated for an actual microgrid distribution network of Malaysia. The demonstration of this intelligent control scheme highlights the advantage of utilizing the fast power recovery response of energy storage and standby generator, which fulfil the criteria for minimal load shedding from the main grid, during the unintentional microgrid islanding conditions
Two-body Cabibbo-suppressed Decays of Charmed Baryons into Vector Mesons and into Photons
The heavy quark effective theory and the factorization approximation are used
to treat the Cabibbo-suppressed decays of charmed baryons to vector mesons,
,
and . The input from two recent experimental results on
decays allows the estimation of the branching ratios for these modes, which
turn out to be between and . The long distance contribution
of these transitions via vector meson dominance to the radiative weak processes
, and
leads to quite small branching ratios,
; the larger value holds if a sum rule between the coupling
constants of the vector mesons is broken.Comment: 11 pages, latex, no figure
Hyperon Nonleptonic Weak Decays Revisited
We first review the current algebra - PCAC approach to nonleptonic octet
baryon 14 weak decay B (\to) (B^{\prime})(\pi) amplitudes. The needed four
parameters are independently determined by (\Omega \to \Xi \pi),(\Lambda K) and
(\Xi ^{-}\to \Sigma ^{-}\gamma) weak decays in dispersion theory tree order. We
also summarize the recent chiral perturbation theory (ChPT) version of the
eight independent B (\to) (B^{\prime}\pi) weak (\Delta I) = 1/2 amplitudes
containing considerably more than eight low-energy weak constants in one-loop
order.Comment: 10 pages, RevTe
Nonfactorization in Hadronic Two-body Cabibbo-favored decays of D^0 and D^+
With the inclusion of nonfactorized amplitudes in a scheme with , we
have studied Cabibbo-favored decays of and into two-body hadronic
states involving two isospins in the final state. We have shown that it is
possible to understand the measured branching ratios and determined the sizes
and signs of nonfactorized amplitudes required.Comment: 15 pages, Late
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