856 research outputs found
The Schwinger SU(3) construction - I: Multiplicity problem and relation to induced representations
The Schwinger oscillator operator representation of SU(3) is analysed with
particular reference to the problem of multiplicity of irreducible
representations. It is shown that with the use of an unitary
representation commuting with the SU(3) representation, the infinity of
occurrences of each SU(3) irreducible representation can be handled in complete
detail. A natural `generating representation' for SU(3), containing each
irreducible representation exactly once, is identified within a subspace of the
Schwinger construction; and this is shown to be equivalent to an induced
representation of SU(3).Comment: Latex, 25 page
PHOTOVOLTAIC BASED FLEXIBLE MICROGRID SYSTEM USING FUZZY LOGIC
This paper presents a flexible ac distribution system device for microgrid applications. The device aims to improve the power quality and reliability of the overall power distribution system that the microgrid is connected to. The control design employs a new model predictive control algorithm which allows faster computational time for large power systems by optimizing the steady-state and the transient control problems separately. In this paper Fuzzy logic controlling technique has been introduced to extract the harmonic spectra of the grid voltage and the load currents in the microgrid. The design concept is verified through different test case scenarios to demonstrate the capability of the proposed device and the Matlab/Simulink results are Presented
Control Barrier Functions in UGVs for Kinematic Obstacle Avoidance: A Collision Cone Approach
In this paper, we propose a new class of Control Barrier Functions (CBFs) for
Unmanned Ground Vehicles (UGVs) that help avoid collisions with kinematic
(non-zero velocity) obstacles. While the current forms of CBFs have been
successful in guaranteeing safety/collision avoidance with static obstacles,
extensions for the dynamic case with torque/acceleration-controlled unicycle
and bicycle models have seen limited success. Moreover, with these nonholonomic
UGV models, applications of existing CBFs have been conservative in terms of
control, i.e., steering/thrust control has not been possible under certain
common scenarios. Drawing inspiration from the classical use of collision cones
for obstacle avoidance in path planning, we introduce its novel CBF formulation
with theoretical guarantees on safety for both the unicycle and bicycle models.
The main idea is to ensure that the velocity of the obstacle w.r.t. the vehicle
is always pointing away from the vehicle. Accordingly, we construct a
constraint that ensures that the velocity vector always avoids a cone of
vectors pointing at the vehicle. The efficacy of this new control methodology
is experimentally verified on the Copernicus mobile robot. We further extend it
to the bicycle model and demonstrate collision avoidance under various
scenarios in the CARLA simulator.Comment: Submitted to 2023 IEEE/RSJ International Conference on Intelligent
Robots and Systems (IROS). 8 pages, 8 figures, For supplement video follow
https://youtu.be/4qWYaWEPduM. The first and second authors have contributed
equall
Over-expression of 60s ribosomal L23a is associated with cellular proliferation in SAG resistant clinical isolates of Leishmania donovani
Background: Sodium antimony gluconate (SAG) unresponsiveness of Leishmania donovani (Ld) had effectively compromised the chemotherapeutic potential of SAG. 60s ribosomal L23a (60sRL23a), identified as one of the over-expressed protein in different resistant strains of L. donovani as observed with differential proteomics studies indicates towards its possible involvement in SAG resistance in L. donovani. In the present study 60sRL23a has been characterized for its probable association with SAG resistance mechanism. Methodology and principal findings: The expression profile of 60s ribosomal L23a (60sRL23a) was checked in different SAG resistant as well as sensitive strains of L. donovani clinical isolates by real-time PCR and western blotting and was found to be up-regulated in resistant strains. Ld60sRL23a was cloned, expressed in E.coli system and purified for raising antibody in swiss mice and was observed to have cytosolic localization in L.donovani. 60sRL23a was further over-expressed in sensitive strain of L. donovani to check its sensitivity profile against SAG (Sb V and III) and was found to be altered towards the resistant mode. Conclusion/Significance: This study reports for the first time that the over expression of 60sRL23a in SAG sensitive parasite decreases the sensitivity of the parasite towards SAG, miltefosine and paramomycin. Growth curve of the tranfectants further indicated the proliferative potential of 60sRL23a assisting the parasite survival and reaffirming the extra ribosomal role of 60sRL23a. The study thus indicates towards the role of the protein in lowering and redistributing the drug pressure by increased proliferation of parasites and warrants further longitudinal study to understand the underlying mechanism
Traumatic Acute Posterior Fossa Subdural Hematoma -A case report and review of literature
Abstract Traumatic subdural hematomas of the posterior fossa are rare but dangerous neurosurgical emergencies that require prompt diagnosis and management to avoid the uniformly poor outcome. We present a case of a teenager with severe TBI and acute subdural hematoma of the posterior fossa that deteriorated rapidly before surgery but eventually made a good recovery. We also the review the literature concerning traumatic posterior fossa subdural hematomas [PFSDH]
Inner wellbeing: concept and validation of a new approach to subjective perceptions of wellbeing-India
© The Author(s) 2013. This article is published with open access at Springerlink.com. This article is distributed under the terms of the Creative Commons Attribution License which permits any use, distribution, and reproduction in any medium, provided the original author(s) and the source are credited.This paper describes the conceptual development of a multi-domain, psychosocial model of 'Inner Wellbeing' (IWB) and assesses the construct validity of the scale designed to measure it. IWB expresses what people think and feel they are able to be and do. Drawing together scholarship in wellbeing and international development it is grounded in field research in marginalised, rural communities in the global South. Results from research in India at two points in time (2011 and 2013) are reported. At Time 1 (n = 287), we were unable to confirm an eight-factor, correlated model as distinct yet interrelated domains. However, at Time 2 (n = 335), we were able to confirm a revised, seven-factor correlated model with economic confidence, agency and participation, social connections, close relationships, physical and mental health, competence and self-worth, and values and meaning (five items per domain) as distinct yet interrelated domains. In particular, at Time 2, a seven-factor, correlated model provided a significantly better fit to the data than did a one-factor model.This work is supported by the Economic and Social Research Council/Department for
International Development Joint Scheme for Research on International Development (Poverty Alleviation)
grant number RES-167-25-0507 ES/H033769/1. Special thanks are due to Chaupal and Gangaram Paikra,
Pritam Das, Usha Kujur, Kanti Minjh, Susanna Siddiqui, and Dinesh Tirkey
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