415 research outputs found
Study of decays to the final state by using , and resonances and weak annihilation nonresonant topologys
In this research the weak decay of decays to the final
state, which is observed by LHCb collaboration for the first time, is
calculated in the quasi-two-body decays which takes into account the ,
and resonances and weak annihilation nonresonant
contributions. In this process, the meson decays first into
, and intermediate states, and then the
, and resonances decay into components, which
undergo final state interaction. The mode of the is also associated to the calculation, in this
mode the intermediate resonance decays to the final mesons.
The resonances , and effects in the , and decays are described in terms of the
quasi-two-body modes. There is a weak annihilation nonresonant contribution in
which decays to the directly, so the point-like 3-body
matrix element is also considered. The
decay mode of the is contributed to the
annihilation contribution. The branching ratios of quasi-two-body decays expand
in the range from to
Estimating the branching fraction for decay
I present estimates of the branching fractions in the non-leptonic charmonium
two-body decay rates for decay and the same
decays of , and
. These estimates are based on a generalized
factorization approach making use of leading order (LO) and next-to-leading
order (NLO) contributions. I find that when the large enhancements from the
known NLO contributions by using the QCD factorization approach are taken into
account, the branching ratios are the following: , , and , while the experimental results are
, , and respectively. All
estimates are in good agreement with the experimental results
Estimated of violation in meson decays into and mesons
The decay is favorable mode for studying
violation in the interference between mixing and decay for and
mesons. The latest analysis of the parameters has been
performed by the LHCb collaboration values of
, ,
, , and
. We have been estimated
the parameters and of the
decay as and . In the following, we have
obtained the values of and and direct violation of . Also, we
have calculated the branching ratio of decay. The
values obtained in this work are comparable with the corresponding experimental
values
Measurement of the Quasi-Two-Body B Decays
We study the contributions of the , and and quasi-two-body decays. There
are no existing previous measurement of the three-body branching fractions for
three final states of the ,
and but several quasi-two-body modes that can decay to this final
state have been seen
Short-term Self-Scheduling of Virtual Energy Hub Plant within Thermal Energy Market
Multicarrier energy systems create new challenges as well as opportunities in future energy systems. One of these challenges is the interaction among multiple energy systems and energy hubs in different energy markets. By the advent of the local thermal energy market in many countries, energy hubs' scheduling becomes more prominent. In this article, a new approach to energy hubs' scheduling is offered, called virtual energy hub (VEH). The proposed concept of the energy hub, which is named as the VEH in this article, is referred to as an architecture based on the energy hub concept beside the proposed self-scheduling approach. The VEH is operated based on the different energy carriers and facilities as well as maximizes its revenue by participating in the various local energy markets. The proposed VEH optimizes its revenue from participating in the electrical and thermal energy markets and by examining both local markets. Participation of a player in the energy markets by using the integrated point of view can be reached to a higher benefit and optimal operation of the facilities in comparison with independent energy systems. In a competitive energy market, a VEH optimizes its self-scheduling problem in order to maximize its benefit considering uncertainties related to renewable resources. To handle the problem under uncertainty, a nonprobabilistic information gap method is implemented in this study. The proposed model enables the VEH to pursue two different strategies concerning uncertainties, namely risk-averse strategy and risk-seeker strategy. For effective participation of the renewable-based VEH plant in the local energy market, a compressed air energy storage unit is used as a solution for the volatility of the wind power generation. Finally, the proposed model is applied to a test case, and the numerical results validate the proposed approach
A comprehensive review on brushless doubly-fed reluctance machine
© 2021 by the authors. Licensee MDPI, Basel, Switzerland. The Brushless Doubly-Fed Reluctance Machine (BDFRM) has been widely investigated in numerous research studies since it is brushless and cageless and there is no winding on the rotor of this emerging machine. This feature leads to several advantages for this machine in comparison with its induction counterpart, i.e., Brushless Doubly-Fed Induction Machine (BDFIM). Less maintenance, less power losses, and also more reliability are the major advantages of BDFRM compared to BDFIM. The design complexity of its reluctance rotor, as well as flux patterns for indirect connection between the two windings mounted on the stator including power winding and control winding, have restricted the development of this machine technology. In the literature, there is not a comprehensive review of the research studies related to BDFRM. In this paper, the previous research studies are reviewed from different points of view, such as operation, design, control, transient model, dynamic model, power factor, Maximum Power Point Tracking (MPPT), and losses. It is revealed that the BDFRM is still evolving since the theoretical results have shown that this machine operates efficiently if it is well-designed
A comprehensive review on brushless doubly-fed reluctance machine
The Brushless Doubly-Fed Reluctance Machine (BDFRM) has been widely investigated in numerous research studies since it is brushless and cageless and there is no winding on the rotor of this emerging machine. This feature leads to several advantages for this machine in comparison with its induction counterpart, i.e., Brushless Doubly-Fed Induction Machine (BDFIM). Less maintenance, less power losses, and also more reliability are the major advantages of BDFRM compared to BDFIM. The design complexity of its reluctance rotor, as well as flux patterns for indirect connection between the two windings mounted on the stator including power winding and control winding, have restricted the development of this machine technology. In the literature, there is not a comprehensive review of the research studies related to BDFRM. In this paper, the previous research studies are reviewed from different points of view, such as operation, design, control, transient model, dynamic model, power factor, Maximum Power Point Tracking (MPPT), and losses. It is revealed that the BDFRM is still evolving since the theoretical results have shown that this machine operates efficiently if it is well-designed
Tidal supplementary control schemes-based load frequency regulation of a fully sustainable marine microgrid
The world is targeting fully renewable power generation by the middle of the century. Distributed generation is the way to increase the penetration level of renewable energies. This paper presents load frequency control of a hybrid tidal, wind, and wave microgrid to feed an isolated island. This research is a step towards 100% renewable energy communities in remote seas/oceans islands. The wave and tidal generation systems model are presented. The study presents load frequency control through three supplementary control strategies: conventional integrators, fractional order integrator, and non-linear fractional order integrator. All the controllers of the microgrid are designed by using a novel black widow optimization technique. The applied technique is compared to other existing state-of-the-art algorithms. The results show that the black widow non-linear fractional integrator has a better performance over other strategies. Coordination between the unloaded tidal system and blade pitch control of both wind and tidal systems are adopted in the microgrid to utilize the available reserve power for the frequency support. Simulation and optimization studies are performed using the MATLAB/SIMULINK 2017a software application
Wild Goats Optimization Approach for Capacitor Placement Problem
This paper deals with Capacitor Placement (CP) issue. The topic is an optimization problem including two types of variables: capacitor location as an integer variable, capacitor size as a continuous one. To cope with this problem, a new approach entitled Wild Goats Algorithm (WGA) is used. WGA is a new heuristic approach which has been proved recently. In this paper, WGA is successfully implemented to the CP problem with the objective of total loss reduction. Power flow criteria as well as operation constraints are all together accommodated in the process of optimization. Two various scenarios at three load levels are also recognized to cover all possible conditions. The validity of the WGA approach in handling CP problem is assured by testifying it on IEEE 33-bus and 69-bus test systems
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