2,911 research outputs found
Isolating the chiral magnetic effect from backgrounds by pair invariant mass
Topological gluon configurations in quantum chromodynamics induce quark
chirality imbalance in local domains, which can result in the chiral magnetic
effect (CME)--an electric charge separation along a strong magnetic field.
Experimental searches for the CME in relativistic heavy ion collisions via the
charge-dependent azimuthal correlator () suffer from large
backgrounds arising from particle correlations (e.g. due to resonance decays)
coupled with the elliptic anisotropy. We propose differential measurements of
the as a function of the pair invariant mass (), by
restricting to high thus relatively background free, and by
studying the dependence to separate the possible CME signal from
backgrounds. We demonstrate by model studies the feasibility and effectiveness
of such measurements for the CME search.Comment: 16 preprint pages 5 figures. v2: added a test with a broad
"instanton/sphaleron" peak, and added clarifying texts; v3: added event-shape
engineering (and two new figures) and expanded discussions on the low
invariant mass region; v4: repeated cautionary discussions in introduction
and conclusion sections, published versio
Hesitant Fuzzy Soft Set and Its Applications in Multicriteria Decision Making
Molodtsov’s soft set theory is a newly emerging mathematical tool to handle uncertainty. However, the classical soft sets are not appropriate to deal with imprecise and fuzzy parameters. This paper aims to extend the classical soft sets to hesitant fuzzy soft sets which are combined by the soft sets and hesitant fuzzy sets. Then, the complement, “AND”, “OR”, union and intersection operations are defined on hesitant fuzzy soft sets. The basic properties such as DeMorgan’s laws and the relevant laws of hesitant fuzzy soft sets are proved. Finally, with the help of level soft set, the hesitant fuzzy soft sets are applied to a decision making problem and the effectiveness is proved by a numerical example
Enhanced Channel Estimation Algorithm for Dedicated Short-Range Communication Systems
The Dedicated Short-Range Communication (DSRC) has been widely accepted as a promising wireless technology for enhancing traffic safety. In such DSRC-based vehicle-to-vehicle (V2V) communication systems, because of the extremely time-varying characteristic of wireless propagation channels, accurate channel estimation is essential for reliable information exchange between vehicles. In this paper, the characteristics of the propagation channel and several traditional channel estimation schemes for V2V communications are reviewed. Then, a delay-based channel-frequency-response decomposition scheme is proposed to estimate and predict the double-selective V2V channel while adhering to the IEEE 802.11p standard. The proposed method achieves a more favorable performance than the traditional methods in V2V scenarios by combining the least square estimation in the frequency domain with the linear prediction in time domain. The performance advantages of the proposed scheme are verified by the simulation results from three typical scenarios. Furthermore, a reference design on a field-programmable gate array for the proposed channel estimation scheme is presented for the purpose of demonstrating its implementation feasibility and complexity
Mining Site Reclamation Planning Based on Land Suitability Analysis and Ecosystem Services Evaluation: A Case Study in Liaoning Province, China
Restoration of the degraded ecosystem is a global priority for achieving sustainable development. Although increasing ecosystem service is an important goal of ecological restoration, it is rarely used to inform mine reclamation. This study proposed a reclamation strategy that incorporated land suitability analysis and ecosystem service evaluation for a mining site in Liaoning Province, China. We assessed the land suitability for three reclamation alternatives and identified suitable land uses for each location by comparing their suitability levels. For areas that were suitable for multiple land uses with the same suitability level, the future land uses cannot be identified by land suitability analysis alone, and we employed ecosystem services evaluation to determine the optimal reclamation strategy. The results showed that forest could be restored throughout the entire mining site, agricultural land were most suitable in the western and southern parts, and developed land were in northern parts that were closer to roads and city centers. Our study showed that a large mining site can be reclaimed to different land uses and provided a practical framework for integrating ecosystem services into mine reclamation
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