| 1. |
- Kristanl, Matej, et al.
(författare)
-
The Seventh Visual Object Tracking VOT2019 Challenge Results
- 2019
-
Ingår i: 2019 IEEE/CVF INTERNATIONAL CONFERENCE ON COMPUTER VISION WORKSHOPS (ICCVW). - : IEEE COMPUTER SOC. - 9781728150239 ; , s. 2206-2241
-
Konferensbidrag (refereegranskat)abstract
- The Visual Object Tracking challenge VOT2019 is the seventh annual tracker benchmarking activity organized by the VOT initiative. Results of 81 trackers are presented; many are state-of-the-art trackers published at major computer vision conferences or in journals in the recent years. The evaluation included the standard VOT and other popular methodologies for short-term tracking analysis as well as the standard VOT methodology for long-term tracking analysis. The VOT2019 challenge was composed of five challenges focusing on different tracking domains: (i) VOT-ST2019 challenge focused on short-term tracking in RGB, (ii) VOT-RT2019 challenge focused on "real-time" short-term tracking in RGB, (iii) VOT-LT2019 focused on long-term tracking namely coping with target disappearance and reappearance. Two new challenges have been introduced: (iv) VOT-RGBT2019 challenge focused on short-term tracking in RGB and thermal imagery and (v) VOT-RGBD2019 challenge focused on long-term tracking in RGB and depth imagery. The VOT-ST2019, VOT-RT2019 and VOT-LT2019 datasets were refreshed while new datasets were introduced for VOT-RGBT2019 and VOT-RGBD2019. The VOT toolkit has been updated to support both standard short-term, long-term tracking and tracking with multi-channel imagery. Performance of the tested trackers typically by far exceeds standard baselines. The source code for most of the trackers is publicly available from the VOT page. The dataset, the evaluation kit and the results are publicly available at the challenge website(1).
|
|
| 2. |
- Kristan, Matej, et al.
(författare)
-
The Ninth Visual Object Tracking VOT2021 Challenge Results
- 2021
-
Ingår i: 2021 IEEE/CVF INTERNATIONAL CONFERENCE ON COMPUTER VISION WORKSHOPS (ICCVW 2021). - : IEEE COMPUTER SOC. - 9781665401913 ; , s. 2711-2738
-
Konferensbidrag (refereegranskat)abstract
- The Visual Object Tracking challenge VOT2021 is the ninth annual tracker benchmarking activity organized by the VOT initiative. Results of 71 trackers are presented; many are state-of-the-art trackers published at major computer vision conferences or in journals in recent years. The VOT2021 challenge was composed of four sub-challenges focusing on different tracking domains: (i) VOT-ST2021 challenge focused on short-term tracking in RGB, (ii) VOT-RT2021 challenge focused on "real-time" short-term tracking in RGB, (iii) VOT-LT2021 focused on long-term tracking, namely coping with target disappearance and reappearance and (iv) VOT-RGBD2021 challenge focused on long-term tracking in RGB and depth imagery. The VOT-ST2021 dataset was refreshed, while VOT-RGBD2021 introduces a training dataset and sequestered dataset for winner identification. The source code for most of the trackers, the datasets, the evaluation kit and the results along with the source code for most trackers are publicly available at the challenge website(1).
|
|
| 3. |
- Alimena, Juliette, et al.
(författare)
-
Searching for long-lived particles beyond the Standard Model at the Large Hadron Collider
- 2020
-
Ingår i: Journal of Physics G. - : IOP Publishing. - 0954-3899 .- 1361-6471. ; 47:9
-
Tidskriftsartikel (refereegranskat)abstract
- Particles beyond the Standard Model (SM) can generically have lifetimes that are long compared to SM particles at the weak scale. When produced at experiments such as the Large Hadron Collider (LHC) at CERN, these long-lived particles (LLPs) can decay far from the interaction vertex of the primary proton-proton collision. Such LLP signatures are distinct from those of promptly decaying particles that are targeted by the majority of searches for new physics at the LHC, often requiring customized techniques to identify, for example, significantly displaced decay vertices, tracks with atypical properties, and short track segments. Given their non-standard nature, a comprehensive overview of LLP signatures at the LHC is beneficial to ensure that possible avenues of the discovery of new physics are not overlooked. Here we report on the joint work of a community of theorists and experimentalists with the ATLAS, CMS, and LHCb experiments-as well as those working on dedicated experiments such as MoEDAL, milliQan, MATHUSLA, CODEX-b, and FASER-to survey the current state of LLP searches at the LHC, and to chart a path for the development of LLP searches into the future, both in the upcoming Run 3 and at the high-luminosity LHC. The work is organized around the current and future potential capabilities of LHC experiments to generally discover new LLPs, and takes a signature-based approach to surveying classes of models that give rise to LLPs rather than emphasizing any particular theory motivation. We develop a set of simplified models; assess the coverage of current searches; document known, often unexpected backgrounds; explore the capabilities of proposed detector upgrades; provide recommendations for the presentation of search results; and look towards the newest frontiers, namely high-multiplicity 'dark showers', highlighting opportunities for expanding the LHC reach for these signals.
|
|
| 4. |
- Hao, Shuwei, et al.
(författare)
-
Enhancing dye-sensitized solar cell efficiency through broadband near-infrared upconverting nanoparticles
- 2017
-
Ingår i: Nanoscale. - : Royal Society of Chemistry. - 2040-3364 .- 2040-3372. ; 9:20, s. 6711-6715
-
Tidskriftsartikel (refereegranskat)abstract
- The inability to utilize near infrared (NIR) light has posed a stringent limitation for the efficiencies of most single-junction photovoltaic cells such as dye-sensitized solar cells (DSSCs). Here, we describe a strategy to alleviate the NIR light harvesting problem by upconverting non-responsive NIR light in a broad spectral range (over 190 nm, 670-860 nm) to narrow solar-cell-responsive visible emissions through incorporated dye-sensitized upconversion nanoparticles (DSUCNPs). Unlike typically reported UCNPs with narrow and low NIR absorption, the organic dyes (IR783) anchored on the DSUCNP surface were able to harvest NIR photons broadly and efficiently, and then transfer the harvested energy to the inorganic UCNPs (typically reported), entailing an efficient visible upconversion. We show that the incorporation of DSUCNPs into the TiO2 photoanode of a DSSC is able to elevate its efficiency from 7.573% to 8.568%, enhancing the power conversion efficiency by about 13.1%. We quantified that among the relative efficiency increase, 7.1% arose from the contribution of broad-band upconversion in DSUCNPs (about similar to 3.4 times higher than the highest previously reported value of similar to 2.1%), and 6.0% mainly from the scattering effect of DSUCNPs. Our strategy has immediate implications for the use of DSUCNPs to improve the performance of other types of photovoltaic devices.
|
|
| 5. |
- Hong, Jie, et al.
(författare)
-
Asymmetrically coupled co single-atom and co nanoparticle in double-shelled carbon-based nanoreactor for enhanced reversible oxygen catalysis
- 2023
-
Ingår i: Chemical Engineering Journal. - : Elsevier. - 1385-8947 .- 1873-3212. ; 455
-
Tidskriftsartikel (refereegranskat)abstract
- Simultaneous construction of size-asymmetric metal single atoms and nanoparticle active sites in advanced and robust carrier materials is particularly important yet challenging for efficient reversible oxygen catalysis. Herein, a facile “chemical etching/in-Situ capture” synthesis strategy was developed to fabricate a unique double-shelled carbon-based nanobox integrated with size-asymmetric Co single-atom (CoSA) and metallic Co nanoparticle (CoNP) moiety. As expected, this well-managed catalyst product yielded remarkable bifunctional electrocatalytic performances in alkaline electrolytes, with a decent half-wave potential of 0.886 V for oxygen reduction reaction (ORR) and a small overpotential of 341 mV at 10 mA/cm2 for oxygen evolution reaction (OER). Besides, this nanobox catalyst served as a cost-effective and efficient oxygen electrode in the assembled rechargeable ZABs, exceeding the mixed electrocatalyst of expensive Pt/C-RuO2, in terms of the elevated peak power density of 239 mW/cm2, the promoted specific capacity of 770 mAh/gZn, as well as the appreciable charge–discharge cycle stability. Theoretical calculations revealed that the strong interaction between the delicate CoSA site and CoNP phase, could effectively optimize the adsorption and desorption energy barriers of reaction intermediates on the designed catalyst surface, thus achieving synergistic enhancement of electrocatalytic activity towards ORR and OER. This finding affords a feasible and effective strategy to achieve highly active and durable bifunctional catalysts for both fundamental research and practical rechargeable ZABs applications.
|
|
| 6. |
- Li, Ziyao, et al.
(författare)
-
Atomic-level orbital coupling in a tri-metal alloy site enables highly efficient reversible oxygen electrocatalysis
- 2023
-
Ingår i: Journal of Materials Chemistry A. - : Royal Society of Chemistry. - 2050-7488 .- 2050-7496. ; 11:5, s. 2155-2167
-
Tidskriftsartikel (refereegranskat)abstract
- Complex multi-metallic alloys with ultra-small sizes have received extensive attention in the fields of Zn-air battery and water splitting, because of their unique advantages including adjustable composition, tailorable active sites, and optimizable electronic structure. In this effort, an atomic-level orbital coupling strategy is presented to effectively regulate the electronic structures of ultra-small tri-metal Fe-Co-Ni nanoalloy particles confined in an N-doped carbon hollow nanobox. As expected, the optimal nanoalloy hybrid material exhibited notable bi-functional catalytic performances toward the oxygen reduction reaction (half-wave potential of 0.902 V) and oxygen evolution reaction (1.589 V at 10 mA cm−2) with a small ΔE of 0.687 V, exceeding the precious-metal-based and many previously reported catalysts. Furthermore, the as-assembled Zn-air device also displayed a superior specific capacity of 894 mA h g−1, a maximal power density of 247 mW cm−2, and impressive durability (over 100 hours). Ultraviolet photoelectron spectroscopy and density functional theory calculations revealed that the electronic structures could be finely tuned and optimized through ternary metal alloying, resulting in a suitable d-band center and advantageous interfacial charge-transfer, which in turn could effectively reduce the involved energy barriers in the electrocatalytic process and significantly boost its intrinsic activity of reversible oxygen catalysis. Thus, this work affords an effective method for the rational creation of bi-functional non-noble-metal-based electrocatalysts for sustainable energy technology.
|
|
| 7. |
- Liu, Tao, et al.
(författare)
-
16% efficiency all-polymer organic solar cells enabled by a finely tuned morphology via the design of ternary blend
- 2021
-
Ingår i: Joule. - : CELL PRESS. - 2542-4351. ; 5:4, s. 914-930
-
Tidskriftsartikel (refereegranskat)abstract
- A SUMMARY There is an urgent demand for all-polymer organic solar cells (AP-OSCs) to gain higher efficiency. Here, we successfully improve the performance to 16.09% by introducing a small amount of BN-T, a B <- N-type polymer acceptor, into the PM6:PY-IT blend. It has been found that BN-T makes the active layer, based on the PM6:PY-IT:BN-T ternary blend, more crystalline but meanwhile slightly reduces the phase separation, leading to enhancement of both exciton harvesting and charge transport. From a thermodynamic viewpoint, BN-T prefers to reside between PM6 and PY-IT, and the fraction of this fine-tunes the morphology. Besides, a significantly reduced nonradiative energy loss occurs in the ternary blend, along with the coexistence of energy and charge transfer between the two acceptors. The progressive performance facilitated by these improved properties demonstrates that AP-OSCs can possibly comparably efficient with those based on small molecule acceptors, further enhancing the competitiveness of this device type.
|
|
| 8. |
- Nie, Zhicheng, et al.
(författare)
-
Tailoring the d-band center by intermetallic charge-transfer manipulation in bimetal alloy nanoparticle confined in N-doped carbon nanobox for efficient rechargeable Zn-air battery
- 2023
-
Ingår i: Chemical Engineering Journal. - : Elsevier. - 1385-8947 .- 1873-3212. ; 463
-
Tidskriftsartikel (refereegranskat)abstract
- In this effort, the electronic-structure modulation strategy through nano-alloying was rationally designed to fabricate Fe-Ni alloy particles embedded in an N-doped carbon nanobox. The as-developed catalyst outperformed the commercialized noble-metal benchmarks with a decent half-wave potential of 0.891 V for ORR and a small overpotential of 325 mV at 10 mA/cm2 for OER both in 0.1 M KOH solution. Beyond that, a highly-efficient regenerative Zn-air battery was also successfully constructed, evidenced by a small potential gap of 0.664 V (between Ej=10 and E1/2), a high specific capacity of 763 mAh/g, a large peak power density of 270 mW/cm2, and robust stability. Ultraviolet photoelectron spectroscopy and theoretical simulation confirmed that the alloying of Ni into Fe could well manipulate the electronic structure, leading to favorable intermetallic charge-transfer and then downshifting the d-band center of Fe adsorption sites, all of which help to significantly lower the reaction barriers of the involved intermediates during the electrocatalytic ORR/OER processes.
|
|
| 9. |
- Peng, Xin, et al.
(författare)
-
Remote detection sulfur content in fuel oil used by ships in emission control areas : A case study of the Yantian model in Shenzhen
- 2021
-
Ingår i: Ocean Engineering. - : Elsevier. - 0029-8018 .- 1873-5258. ; 237
-
Tidskriftsartikel (refereegranskat)abstract
- A method is proposed for remotely detecting sulfur content in fuel oil used by ships in emission control areas (ECAs) based on the direct collection of SO2 emission data from the plume of the ship and numerical simulation models. Assuming a ship in the ECA uses fuel oil with compliance fuel sulfur content (FSC), activity-based ship emission assessment model is firstly utilized to calculate the SO2 concentration emitted from the ship. Numerical simulation models are then used to estimate the theoretical SO2 diffusion concentration at the location of the monitoring equipment. The observed SO2 concentration at the same time can then be integrated to estimate the FSC of the ship. A sample of eleven ships was selected to verify the proposed method in Yantian port, Shenzhen, China in June 2018. The result illustrates that the method can remotely detect ships using fuel oil with the FSC greater than 0.146%m/m in the ECAs, the relative error is 46%.
|
|
| 10. |
- Qiu, Hailong, et al.
(författare)
-
Enhanced Upconversion Luminescence in Yb3+/Tm3+-Codoped Fluoride Active Core/Active Shell/Inert Shell Nanoparticles through Directed Energy Migration
- 2014
-
Ingår i: Nanomaterials. - : MDPI AG. - 2079-4991. ; 4:1, s. 55-68
-
Tidskriftsartikel (refereegranskat)abstract
- The luminescence efficiency of lanthanide-doped upconversion nanoparticles is of particular importance for their embodiment in biophotonic and photonic applications. Here, we show that the upconversion luminescence of typically used NaYF4:Yb(3+)30%/Tm(3+)0.5% nanoparticles can be enhanced by similar to 240 times through a hierarchical active core/active shell/inert shell (NaYF4:Yb(3+)30%/Tm(3+)0.5%)/NaYbF4/NaYF4 design, which involves the use of directed energy migration in the second active shell layer. The resulting active core/active shell/inert shell nanoparticles are determined to be about 11 times brighter than that of well-investigated (NaYF4:Yb(3+)30%/Tm(3+)0.5%)/NaYF4 active core/inert shell nanoparticles when excited at similar to 980 nm. The strategy for enhanced upconversion in Yb3+/Tm3+-codoped NaYF4 nanoparticles through directed energy migration might have implications for other types of lanthanide-doped upconversion nanoparticles.
|
|
