6,712 research outputs found
Hybrid vehicle assessment. Phase 1: Petroleum savings analysis
The results of a comprehensive analysis of near term electric hybrid vehicles are presented, with emphasis on their potential to save significant amounts of petroleum on a national scale in the 1990s. Performance requirements and expected annual usage patterns of these vehicles are first modeled. The projected U.S. fleet composition is estimated, and conceptual hybrid vehicle designs are conceived and analyzed for petroleum use when driven in the expected annual patterns. These petroleum consumption estimates are then compared to similar estimates for projected 1990 conventional vehicles having the same performance and driven in the same patterns. Results are presented in the form of three utility functions and comparisons of sevral conceptual designs are made. The Hybrid Vehicle (HV) design and assessment techniques are discussed and a general method is explained for selecting the optimum energy management strategy for any vehicle mission battery combination. Conclusions and recommendations are presented, and development recommendations are identified
The study of causes, mode of delivery in intrauterine fetal death and associated complications
Background: Intra uterine fetal death (IUFD) is defined as the baby born with no signs of life at or after 28 weeks of gestation. It is important to diagnose the cause in order to avoid further recurrence and to treat any maternal associated factors. The aim of the present study was to calculate incidence of IUFD in our hospital and know the causes, mode of delivery, associated complications. So we can take measures to prevent them in future.Methods: The retrospective study was conducted in the department of Obstetrics and Gynecology in Kanachur Medical College, Mangalore from January 2017 to January 2020. The women with confirmed diagnosis of IUFD on Ultrasound and beyond 28 weeks of gestation were included in the study.Results: In the study period, total 2026 patients delivered, of which 40 cases were IUFD, hence our incidence rate was 19.74 per 1000 population. 62.5% cases were multigravida. 15% had previous history of abortions while 5% previously had IUFD. In 37.5% cases, the cause was unknown, followed by 22.5% having pregnancy induced hypertension. Anemia contributed to 17.5% and placental causes in 12.5%. 10% of the women had PPH. One patient had sepsis, followed by acute renal failure and later died of multi organ failure.Conclusions: All the causes are not preventable, many of them can be identified early in pregnancy and thus IUFD can be prevented. All the high risk pregnancies should undergo antenatal fetal surveillance and should have frequent ante natal visits to reduce IUFD rates
Histopathological changes in the gill architecture of Labeo rohita from the pond adjacent to thermal power station, Koradi, Nagpur, India
The hazardous effect of water pollution on the histopathology of selected organs of the freshwater fish Labeo rohita was studied with respect to thermal power plant effluent. The purpose of this research paper is to study whether the thermal plume can affect fish assemblages in the waters around the outlet area of the thermal power plant located at Koradi near Nagpur city. Both experimental and control fishes were monitored for a year from March 2010 to Feb. 2011. Histopathology serve as a tool to assess the extent of damage caused to the organism.Gill tissue showed fusion of primary lamellae, congestion of blood vessels and hyperplasia of bronchial plates. The histopathological changes in the gill tissue include epithelial hyperplasia, curling of secondary lamellae and changes in chloride cells. Besides these changes pyknotic nuclei, vacuolization, degradation of epithelial and pillar cells, were noticed, which point out towards deleterious effect of thermal power plant effluent on the freshwater fish L. rohita
Electroweak Model Independent Tests for SU(3) Symmetry in Hadronic B Decays
We study effects of new physics beyond the Standard Model on SU(3) symmetry
in charmless hadronic two body B decays. It is found that several equalities
for some of the decay amplitudes, such as , , , predicted by SU(3) symmetry in the SM are not affected by new
physics. These relations provide important electroweak model independent tests
for SU(3) symmetry in B decays.Comment: 4 pages, revte
Examination of the Resonance Contributions to Dileptonic Rare B-Decays
We analyse the long-distance contribution to
differential decay rate when the momentum dependence of and
- conversion strength is taken into account. The results
indicate that the resonance to nonresonance interference in the dilepton
invariant mass distribution is substantially reduced.Comment: 10 pages, Latex, one figure (included
Surface-Chemical Studies on Graphite Suspensions using Inorganic Disperants
Electrokinetic and dispersion characteristics of graphite suspensions were studied in the absence and presence of varying concentrations of different inorganic dispersants, namely sodium silicate, sodium hexametaphosphate and sodium tripolyphosphate. The isoelectric point of graphite was found to be located at pH 2.3. From the zeta potential data obtained as a function of pH in the presence of varying concentrations of the dispersants, it was observed
that the phosphate based inorganic dispersants were more efficient in enhancing the electronegative character of zeta potential. Thus, better stability of the graphite suspension could be obtained using the phosphate based dispersants. The results of the dispersion tests corrobo-rated the zeta potential data. The electron microscopic studies indicated that the graphite particles obtained from the supernatant were finer than those in the settled portion
Constraints on the phase and new physics from Decays
Recent results from CLEO on indicate that the phase may
be substantially different from that obtained from other fit to the KM matrix
elements in the Standard Model. We show that extracted using is sensitive to new physics occurring at loop level. It provides
a powerful method to probe new physics in electroweak penguin interactions.
Using effects due to anomalous gauge couplings as an example, we show that
within the allowed ranges for these couplings information about
obtained from can be very different from the Standard
Model prediction.Comment: Revised version with analysis done using new data from CLEO. RevTex,
11 Pages with two figure
Relating Green's Functions in Axial and Lorentz Gauges using Finite Field-Dependent BRS Transformations
We use finite field-dependent BRS transformations (FFBRS) to connect the
Green functions in a set of two otherwise unrelated gauge choices. We choose
the Lorentz and the axial gauges as examples. We show how the Green functions
in axial gauge can be written as a series in terms of those in Lorentz gauges.
Our method also applies to operator Green's functions. We show that this
process involves another set of related FFBRS transfomations that is derivable
from infinitesimal FBRS. We suggest possible applications.Comment: 20 pages, LaTex, Section 4 expanded, typos corrected; last 2
references modified; (this) revised version to appear in J. Math. Phy
Effects of R-parity violation on direct CP violation in B decays and extraction of
In the standard model, direct CP-violating asymmetries for are roughly 2% based on perturbative calculation. Rescattering effects might
enhance it to at most (20-25)%. We show that lepton-number-violating couplings
in supersymmetric models without R-parity are capable of inducing as large as
100% CP asymmetry in this channel. Such effects drastically modify the allowed
range of the CKM parameter arising from the combinations of the
observed charged and neutral B decays in the modes. With a multichannel
analysis in B decays, one can either discover this exciting new physics, or
significantly improve the existing constraints on it.Comment: Latex, 5 pages; minor changes, to appear in Phys Rev Let
The CP violating phase from global fit of rare charmless hadronic B decays
We study constraints on the CP violating phase in the
Kobayashi-Maskawa model using available experimental data. We first follow the
conventional method to up date the constraint on by performing a
analysis using data from , and
. We also include the recent information on in
the analysis. We obtain the best fit for to be and the 95%
C.L. allowed range to be . We then develop a method to
carry out a analysis based on SU(3) symmetry using data from and . We also discuss SU(3) breaking effects from model
estimate. We find that present data on can also give some
constraint on although weaker than the earlier method limited by the
present experimental errors. Future improved data will provide more stringent
constraint. Finally we perform a combined fit using data from ,
, , and rare charmless
hadronic B decays. The combined analysis gives for the best
fit value and as the 95% C.L. allowed range. Several
comments on other methods to determine based on SU(3) symmetry are
also provided.Comment: Revised verion with the new experimental data from Belle and Babar
included in the analysis to obtain the global fit for the CP violating phase
gamma. RevTex, 32 pages and 8 figure
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