| 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. |
- Amer, Wael A., et al.
(författare)
-
Liquid-crystalline azobenzene-containing ferrocene-based polymers : study on synthesis and properties of main-chain ferrocene-based polyesters with azobenzene in the side chain
- 2013
-
Ingår i: Polymers for Advanced Technologies. - : Wiley. - 1042-7147 .- 1099-1581. ; 24:2, s. 181-190
-
Tidskriftsartikel (refereegranskat)abstract
- Ferrocene-based polymers are characterized by their electrochemical activity, good redox properties, thermal, photochemical stability, and liquid crystallinity, and thus they have various applications in different fields. A comprehensive investigation on the synthesis and properties of three novel main-chain ferrocene-based polyesters with azobenzene in the side chain (MFPAS) was carried out. The main-chain ferrocene-based polyester, poly(N-phenyldiethanolamine 1,1'-ferrocene dicarboxylate (PPFD), was synthesized via the solution polycondensation reaction of 1,1'-ferrocenedicarbonyl chloride with phenyldiethanolamine (PDE). The novel MFPAS were synthesized via the post-polymerization azo-coupling reaction of PPFD with three different 4-substituted anilines including 4-nitroaniline, 4-aminobenzoic acid, and 4-aminobenzonitrile to produce 4-nitrophenylazo-functionalized-PPFD (PPFD-NT), 4-carboxyphenylazo-functionalized-PPFD (PPFD-CA), and 4-cyanophenylazo-functionalized-PPFD (PPFD-CN), respectively. All the synthesized polymers were characterized by 1H NMR spectroscopy, Fourier transform infrared spectroscopy, and UVvisible spectroscopy. In addition, powder X-ray diffraction patterns were measured for the synthesized polymers. The photoisomerization of the MFPAS was studied. The thermal properties of the MFPAS were studied using thermogravimetric analysis and differential scanning calorimetry. PPFD-CA and PPFD-CN were found to be more thermally stable than PPFD-NT. Finally, the liquid-crystalline properties of PPFD and the MFPAS were examined using polarized optical microscope. It was found that all the polymers possessed nematic phases and exhibited textures with schlieren disclinations.
|
|
| 3. |
- Amer, Wael A., et al.
(författare)
-
Synthesis and Properties of a Ferrocene-based Metallomesogenic Polymer Containing Bis(4-hydroxyoctoxyphenyl)sulfone
- 2012
-
Ingår i: Journal of Inorganic and Organometallic Polymers and Materials. - : Springer Nature. - 1574-1443 .- 1574-1451. ; 22:6, s. 1229-1239
-
Tidskriftsartikel (refereegranskat)abstract
- Poly[bis(4-hydroxyoctoxyphenyl)sulfone 1,1'-ferrocene dicarboxylate] (PHOSFD) was synthesized by solution polycondensation reaction of bis(4-hydroxyoctoxyphenyl)sulfone with 1,1'-ferrocenyl chloride. The synthesized polymer was characterized via the measurement of its H-1 NMR spectrum, UV-Vis spectrum and FTIR spectrum. X-ray diffraction pattern was measured to investigate the crystallinity of the synthesized polymer and it was found that the polymer is mostly amorphous. The molecular weight of the polymer was determined by gel permeation chromatography. In addition, the electrochemical, the thermal, and the liquid crystalline properties of the synthesized polymer were examined and compared with the properties of poly(diethyleneglycol 1,1'-ferrocene dicarboxylate) (PDEFD) that was synthesized in our earlier study. The electrochemical processes of PHOSFD in CH2Cl2 were confirmed neither to be totally reversible nor completely irreversible. Generally, the electrochemical properties of PHOSFD and PDEFD were found to be similar to each other. PHOSFD was found to be thermally stable but its thermal stability is lower than that of PDEFD. Both of PHOSFD and PDEFD showed liquid crystalline properties and they possessed nematic phase textures with schlieren disclinations during heating and cooling.
|
|
| 4. |
- Liu, Chunyu, et al.
(författare)
-
Experimental study on effects of ammonia enrichment on the thermoacoustic instability of lean premixed swirling methane flames
- 2024
-
Ingår i: Fuel. - 0016-2361. ; 357
-
Tidskriftsartikel (refereegranskat)abstract
- Ammonia (NH3) has recently emerged as a promising carbon-free energy carrier. Further development and application of NH3 as fuel in the gas turbine industry can significantly reduce the emissions of carbon dioxide (CO2) and contribute to the achievement of a carbon–neutral society. This study experimentally examined the thermoacoustic instability characteristics of a laboratory-scaled lean premixed gas turbine model combustor operated with different NH3 blending ratios with methane (CH4). Experiments conducted under a wide range of inlet velocities and equivalence ratios suggest that NH3 concentration is critical in determining the characteristics of the instability. Specifically, when the NH3 proportion is less than 50 %, the addition of NH3 causes a mode transition of the instability. However, when the content of NH3 is greater than 50 %, it is shown that the instabilities are suppressed, indicating that the addition of a certain amount of NH3 can enhance the stability of CH4 flames. Additional analysis of flame dynamics reveals that the introduction of NH3 causes the lengthening of the flame front and weakens heat release rate fluctuations in the flame root regions. Further Proper Orthogonal Decomposition (POD) analysis of the flow field shows that the instability modes are strongly coupled with periodic vortex motions of the flow dynamics along the shear layers. Finally, the mode shifting phenomena is successfully predicted by low-order thermoacoustic network modeling. It is suggested that the change in convective time delay caused by NH3 addition is responsible for such transitions.
|
|
| 5. |
- Liu, Chunyu, et al.
(författare)
-
Influence of swirl intensity on combustion dynamics and emissions in an ammonia-enriched methane/air combustor
- 2024
-
Ingår i: Physics of Fluids. - 1070-6631. ; 36:3
-
Tidskriftsartikel (refereegranskat)abstract
- Ammonia (NH3) has been widely considered as a promising carbon-free energy and hydrogen carrier for various applications. The large-scale direct utilization of NH3 as fuel in gas turbine engines is currently attracting significant interest, with strong focuses on improving the efficiency and stability of the system and reducing the emissions of pollutants. The present study experimentally examined the impacts of swirl intensity on combustion stability and emissions in an NH3-enriched premixed swirl-stabilized CH4/air combustor under a wide range of equivalence ratios. Simultaneous high-speed OH* chemiluminescence and particle image velocimetry measurements suggested that increasing swirl intensity resulted in more compact flame shapes and expanded the recirculation zone, which promoted flame stability at higher NH3 ratios. However, under specified conditions, enhancing swirl intensity could increase the instability frequency and amplitude of pressure oscillations. The flame dynamics exhibited different behaviors depending on the swirl intensity. At high swirl intensity, the flames underwent high-frequency, small-amplitude periodic motion. At low swirl intensity, the flames oscillated axially with large amplitude and low frequency. For flow dynamics, the stability of the vortex at high swirl intensity contrasted with the periodic vortex shedding at low swirl intensity. Furthermore, the two-dimensional Rayleigh index indicated that the dominant positive thermoacoustic coupling regions were located near the flame shear layers and flame tail at low and high swirl intensities, respectively. Finally, the experimental results showed that swirl intensity affected pollutant emissions by influencing the temperature of combustion chamber and gas mixing efficiency. The pathway of fuel-type NOx was found to be dominant in the NOx emission of the NH3/CH4/air flames.
|
|
| 6. |
- Liu, Qingquan, et al.
(författare)
-
Regeneration Research of Porous Magnetic Microspheres during Treatment of Wastewater Containing Cationic Dyes
- 2010
-
Ingår i: Separation science and technology (Print). - : Informa UK Limited. - 0149-6395 .- 1520-5754. ; 45:16, s. 2345-2349
-
Tidskriftsartikel (refereegranskat)abstract
- The application feasibility of porous magnetic microspheres in the removal of cationic dyes from wastewater was investigated. Various desorption solutions were employed for the recovery of cationic dyes from absorbents and regeneration of porous magnetic microspheres. The results showed that 1M NaCl or 1M KCl in water/methanol co-solvent had excellent desorption ability for methyl violet. This fact was further demonstrated in the removal cationic gold yellow from its aqueous solution. Overall, this provided a simple methodology for the treatment of wastewater containing cationic dyes and the regeneration of porous magnetic microspheres.
|
|
| 7. |
- Liu, Qingquan, et al.
(författare)
-
Templated preparation of porous magnetic microspheres and their application in removal of cationic dyes from wastewater
- 2010
-
Ingår i: Journal of Hazardous Materials. - : Elsevier BV. - 0304-3894 .- 1873-3336. ; 181:1-3, s. 586-592
-
Tidskriftsartikel (refereegranskat)abstract
- Porous magnetic microspheres with large particle size (350-450 mu m) were prepared with sulfonated macroporous polydivinylbenzene as a template. The preparation process included ferrous ion exchange and following oxidation by hydrogen peroxide. The results showed that the weight fraction of magnetic nanoparticles exceeded 20 wt% in microspheres after the preparation process was repeated three times. X-ray diffraction profiles indicated that the crystalline phase of as-formed magnetic nanoparticles was magnetite (Fe3O4). TEM images revealed rod-like magnetite crystal after the first oxidation cycle, however, the crystal morphologies were transferred into random shape after more oxidation cycles. The applicability of porous magnetic microspheres for removal of cationic dyes from water was also explored. The results exhibited that basic fuchsin and methyl violet could be quickly removed from water with high efficiency. More importantly, the magnetic microspheres could be easily regenerated and repeatedly employed for wastewater treatment. Therefore, a novel methodology was provided for fast removal cationic dyes from wastewater.
|
|
| 8. |
- Sun, Ying, et al.
(författare)
-
Joint Exposure to Positive Affect, Life Satisfaction, Depressive Symptoms, and Neuroticism and Incident Type 2 Diabetes
- 2022
-
Ingår i: Journal of Clinical Endocrinology and Metabolism. - : The Endocrine Society. - 0021-972X .- 1945-7197. ; 107:8, s. E3186-E3193
-
Tidskriftsartikel (refereegranskat)abstract
- Context Whether the psychological wellbeing status could be a risk factor for type 2 diabetes is unclear. Objective We aimed to measure the association between combined psychological wellbeing factors and type 2 diabetes and investigate whether this association was modified by genetic predisposition. Methods Prospective cohort study from the UK Biobank. In total, 127 496 participants who completed a psychological wellbeing questionnaire and did not have type 2 diabetes at baseline (2006-2010) were included; among them, 88 584 (69.5%) were analyzed to determine their genetic predisposition. The main outcome measure was incident type 2 diabetes. Results During the median follow-up of 10.0 years, 2547 incident type 2 diabetes cases were documented. Moderate to extreme unhappiness, satisfaction score <= 3, presence of broad depression, and a neuroticism score >= 3 were all significantly and independently associated with an increased risk of diabetes. When considered as a combination indicator, compared with individuals in the highest quartile of the psychological wellbeing score, the fully adjusted hazard ratios (95% CI) of type 2 diabetes were 1.41 (1.21-1.65) in the third quartile, 1.45 (1.24-1.69) in the second quartile, and 1.73 (1.48-2.01) in the lowest quartile. In the stratified analysis, we observed significant interactions between age and physical activity, and type 2 diabetes (P-interaction < .001 and 0.049, respectively). However, there was no significant interaction between the psychological wellbeing score and genetic susceptibility to diabetes (P-interaction = .980). Conclusion Worse overall psychological wellbeing was associated with a significantly increased risk of type 2 diabetes in a dose-response fashion regardless of genetic predisposition.
|
|
| 9. |
- Sun, Ying, et al.
(författare)
-
Replacement of leisure-time sedentary behavior with various physical activities and the risk of dementia incidence and mortality : A prospective cohort study
- 2023
-
Ingår i: Journal of Sport and Health Science. - : SHANGHAI UNIV SPORT. - 2095-2546 .- 2213-2961. ; 12:3, s. 287-294
-
Tidskriftsartikel (refereegranskat)abstract
- Background: Whether or not there is targeted pharmacotherapy for dementia, an active and healthy lifestyle that includes physical activity (PA) may be a better option than medication for preventing dementia. We examined the association between leisure-time sedentary behavior (SB) and the risk of dementia incidence and mortality. We further quantified the effect on dementia risk of replacing sedentary time with an equal amount of time spent on different physical activities.Methods: In the UK Biobank, 484,169 participants (mean age = 56.5 years; 45.2% men) free of dementia were followed from baseline (2006-2010) through July 30, 2021. A standard questionnaire measured individual leisure-time SB (watching TV, computer use, and driving) and PA (walking for pleasure, light and heavy do-it-yourself activity, strenuous sports, and other exercise) frequency and duration in the 4 weeks prior to evaluation. Apolipoprotein E (APOE) genotype data were available for a subset of 397,519 (82.1%) individuals. A Cox proportional hazard model and an isotemporal substitution model were used in this study.Results: During a median 12.4 years of follow-up, 6904 all-cause dementia cases and 2115 deaths from dementia were recorded. In comparison to participants with leisure-time SB <5 h/day, the hazard ratio ((HR), 95% confidence interval (95%CI)) of dementia incidence was 1.07 (1.02-1.13) for 5-8 h/day and 1.25 (1.13-1.38) for >8 h/day, and the HR of dementia mortality was 1.35 (1.12-1.61) for >8 h/day. A 1 standard deviation increment of sedentary time (2.33 h/day) was strongly associated with a higher incidence of dementia and mortality (HR = 1.06, 95%CI: 1.03-1.08 and HR = 1.07, 95%CI: 1.03-1.12, respectively). The association between sedentary time and the risk of developing dementia was more profound in subjects <60 years than in those =60 years (HR =1.26, 95%CI: 1.00-1.58 vs. HR = 1.21, 95%CI: 1.08-1.35 in >8 h/day, p for interaction = 0.013). Replacing 30 min/day of leisure sedentary time with an equal time spent in total PA was associated with a 6% decreased risk and 9% decreased mortality from dementia, with exercise (e.g., swimming, cycling, aerobics, bowling) showing the strongest benefit (HR = 0.82, 95%CI: 0.78-0.86 and HR = 0.79, 95%CI: 0.72-0.86). Compared with APOE e4 noncarriers, APOE e4 carriers are more likely to see a decrease in Alzheimer's disease incidence and mortality when PA is substituted for SB.Conclusion: Leisure-time SB was positively associated with the risk of dementia incidence and mortality. Replacing sedentary time with equal time spent doing PA may be associated with a significant reduction in dementia incidence and mortality risk.
|
|
| 10. |
- Wang, Ningjian, et al.
(författare)
-
Acquired risk factors and incident atrial fibrillation according to age and genetic predisposition
- 2023
-
Ingår i: European Heart Journal. - : Oxford University Press. - 0195-668X .- 1522-9645. ; 44:47, s. 4982-4993
-
Tidskriftsartikel (refereegranskat)abstract
- Background and Aims: Atrial fibrillation (AF) is the most common sustained arrhythmia in adults. Investigations of risk factor profiles for AF according to age and genetic risk groups are essential to promote individualized strategies for the prevention and control of AF.Methods: A total of 409 661 participants (mean age, 56 years; 46% men) free of AF at baseline and with complete information about risk factors were included from the UK Biobank cohort. The hazard ratios and population-attributable risk (PAR) percentages of incident AF associated with 23 risk factors were examined, including 3 social factors, 7 health behaviours, 6 cardiometabolic factors, 6 clinical comorbidities, and the genetic risk score (GRS), across 3 age groups (40-49, 50-59, and 60-69 years) and 3 genetic risk groups (low, moderate, and high GRS).Results: After a follow-up of 5 027 587 person-years, 23 847 participants developed AF. Most cardiometabolic factors and clinical comorbidities showed a significant interaction with age, whereby the associations were generally strengthened in younger groups (Pinteraction < .002). However, only low LDL cholesterol, renal dysfunction, and cardiovascular disease showed a significant interaction with genetic risk, and the associations with these factors were stronger in lower genetic risk groups (Pinteraction < .002). Cardiometabolic factors consistently accounted for the largest number of incident AF cases across all age groups (PAR: 36.2%-38.9%) and genetic risk groups (34.0%-41.9%), with hypertension and overweight/obesity being the two leading modifiable factors. Health behaviours (PAR: 11.5% vs. 8.7%) and genetic risk factors (19.1% vs. 14.3%) contributed to more AF cases in the 40-49 years group than in the 60-69 years group, while the contribution of clinical comorbidities remained relatively stable across different age groups. The AF risk attributable to overall cardiometabolic factors (PAR: 41.9% in the low genetic risk group and 34.0% in the high genetic risk group) and clinical comorbidities (24.7% and 15.9%) decreased with increasing genetic risk. The impact of social factors on AF was relatively low across the groups by age and genetic risk.Conclusions: This study provided comprehensive information about age- and genetic predisposition-related risk factor profiles for AF in a cohort of UK adults. Prioritizing risk factors according to age and genetic risk stratifications may help to achieve precise and efficient prevention of AF.
|
|
