287 research outputs found
Technical And Economic Impacts Of Distributed Generators And Energy Storage Devices On The Electric Grid
In recent years, Distributed Generators (DGs) and energy storage devices have gained more popularity due to growing energy and environmental concerns. Interconnection of DGs and storage devices in an electricity grid impacts its performance under steady state and transient conditions. This research aims at analyzing the impacts of distributed generators and energy storage devices on the transient stability of the grid. Battery and ultra-capacitor technologies have been taken as the two types of storage devices and their electrical characteristics have been modeled using Simulink. Impact of these devices has been analyzed by connecting them to the system by means of suitable power electronic converters. The developed methodology has been evaluated using small test systems in MATLAB/Simulink. Transient stability of the test systems has been assessed for different types and locations of faults as well as for different penetration levels of the DGs, with and without the energy storage devices. Impact on the system transient stability has been analyzed based on transient response of the generator rotor speed deviation, rotor angle and terminal voltage of the DGs. Finally, economic analyses have been carried out for different options of DGs, based on wind, diesel and biomass, along with the energy storage devices. Results indicate that the presence of DGs and storage devices enhances the transient stability of the system in most of the cases
Algebraic vector bundles on spheres
We determine the first non-stable -homotopy sheaf of .
Using techniques of obstruction theory involving the -Postnikov
tower, supported by some ideas from the theory of unimodular rows, we classify
vector bundles of rank on split smooth affine quadrics of dimension
. These computations allow us to answer a question posed by Nori, which
gives a criterion for completability of certain unimodular rows. Furthermore,
we study compatibility of our computations of -homotopy sheaves
with real and complex realization.Comment: 35 pages; final version (before page proofs) to appear J. Top.
Significantly reorganized and incorporates some material from
http://arxiv.org/abs/1204.0770 (which will also soon be replaced
Preparation of Gefitinib Loaded Polycaprolactone Microcapsule For Controlled Release Drug Delivery System
- The aim of the study was to prepare gefitinib-loaded polycaprolactone microcapsules by simple conventional solvent evaporation method with a view to achieve controlled release of the drug following subcutaneous administration once in a week for targeted therapeutic action especially locally. The microcapsules were prepared using different drug-polymer ratios (1:2, 1:4 and 1:6) and three different stabilizers/surfactants (0.25% w/v, 0.50% w/v and 0.75% w/v) concentrations in aqueous phase. Depending upon the formulation variables, the highest drug entrapment efficiency and the lowest average particle size diameter of the microcapsules were found to be respectively 90.19±2.61 % and 201±3.05 µ. Comparison of Fourier Transform Infra Red spectra of gefitinib, polycaprolactone, their physical mixture and the drug- loaded microcapsules showed the absence of drug -polymer interaction .The in-vitro dissolution study showed that the release of drug from the microcapsules was almost complete on day seventh and the drug release followed Higuchi model
Which verification qubits perform best for secure communication in noisy channel?
In secure quantum communication protocols, a set of single qubits prepared
using 2 or more mutually unbiased bases or a set of -qubit ()
entangled states of a particular form are usually used to form a verification
string which is subsequently used to detect traces of eavesdropping. The qubits
that form a verification string are referred to as decoy qubits, and there
exists a large set of different quantum states that can be used as decoy
qubits. In the absence of noise, any choice of decoy qubits provides equivalent
security. In this paper, we examine such equivalence for noisy environment
(e.g., in amplitude damping, phase damping, collective dephasing and collective
rotation noise channels) by comparing the decoy-qubit assisted schemes of
secure quantum communication that use single qubit states as decoy qubits with
the schemes that use entangled states as decoy qubits. Our study reveals that
the single qubit assisted scheme perform better in some noisy environments,
while some entangled qubits assisted schemes perform better in other noisy
environments. Specifically, single qubits assisted schemes perform better in
amplitude damping and phase damping noisy channels, whereas a few
Bell-state-based decoy schemes are found to perform better in the presence of
the collective noise. Thus, if the kind of noise present in a communication
channel (i.e., the characteristics of the channel) is known or measured, then
the present study can provide the best choice of decoy qubits required for
implementation of schemes of secure quantum communication through that channel.Comment: 11 pages, 4 figure
Autism and mental retardation with convulsion in tuberous sclerosis: a case report
A 6-year-old male child born of a non-consanguineous marriage admitted in the pediatrics emergency ward with the history of recurrent attacks of convulsion since 4 month of age. He was also suffering from frequent vomiting. Examination revealed that the child had characteristics features of angiofibromas on the face with butterfly distribution, hyperpigmented patches on forehead, hypopigmented macules on trunk, prominent subependymal and cortical tubers. The child was diagnosed as tuberous sclerosis. Association of autistic behaviors and severe degree of mental retardation are noteworthy in this child indicating the need of counseling as early as possible along with behavioral and educational strategies for mental retardation from early age with other symptomatic management
Therapeutic evaluation of homeopathic treatment for canine oral papillomatosis
Aim: A study was conducted to evaluate the ameliorative potential of homeopathic drugs in combination (Sulfur 30C, Thuja 30C, Graphites 30C, and Psorinum 30C) in 16 dogs affected with oral papillomatosis which was not undergone any previous treatment.
Materials and Methods: Dogs affected with oral papillomatosis, which have not undergone any initial treatment and fed with a regular diet. Dogs (total=16) were randomly divided into two groups, namely, homeopathic treatment group (n=8) and placebo control group (n=8). Random number table was used for allocation. Homeopathic combination of drugs and placebo drug (distilled water) was administered orally twice daily for 15 days. Clinical evaluation in both groups of dogs was performed by the same investigator throughout the period of study (12 months). Dogs were clinically scored for oral lesions on days 0, 5, 7, 10, 15, 20, 25, 30, 45, 60, 90, 120, and 150 after initiation of treatment.
Results: The homeopathic treatment group showed early recovery with a significant reduction in oral lesions reflected by clinical score (p<0.001) in comparison to placebo-treated group. Oral papillomatous lesions regressed in the homeopathic group between 7 and 15 days, whereas regression of papilloma in the placebo group occurred between 90 and 150 days. The homeopathic treated group was observed for 12 months post-treatment period and no recurrence of oral papilloma was observed.
Conclusion: The current study proves that the combination of homeopathy drugs aids in fastening the regression of canine oral papilloma and proved to be safe and cost-effective
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