Institution
Hong Kong Polytechnic University
Education•Hong Kong, China•
About: Hong Kong Polytechnic University is a education organization based out in Hong Kong, China. It is known for research contribution in the topics: Tourism & Population. The organization has 29633 authors who have published 72136 publications receiving 1956312 citations. The organization is also known as: HKPU & PolyU.
Papers published on a yearly basis
Papers
More filters
••
TL;DR: A robust adaptive control algorithm is developed without constructing a hysteresis inverse, which ensures global stability of the adaptive system and achieves both stabilization and tracking to within a desired precision.
Abstract: Deals with adaptive control of a class of nonlinear dynamic systems preceded by unknown backlash-like hysteresis nonlinearities, where the hysteresis is modeled by a differential equation. By exploiting solution properties of the differential equation and combining those properties with adaptive control techniques, a robust adaptive control algorithm is developed without constructing a hysteresis inverse. The new control law ensures global stability of the adaptive system and achieves both stabilization and tracking to within a desired precision. Simulations performed on a nonlinear system illustrate and clarify the approach.
578 citations
••
TL;DR: In this paper, a detailed simulation of glyoxal and methylglyoxal in the GEOS-Chem global 3-D chemical transport model including the best knowledge of source and sink processes was conducted.
Abstract: [1] We construct global budgets of atmospheric glyoxal and methylglyoxal with the goal of quantifying their potential for global secondary organic aerosol (SOA) formation via irreversible uptake by aqueous aerosols and clouds. We conduct a detailed simulation of glyoxal and methylglyoxal in the GEOS-Chem global 3-D chemical transport model including our best knowledge of source and sink processes. Our resulting best estimates of the global sources of glyoxal and methylglyoxal are 45 Tg a−1 and 140 Tg a−1, respectively. Oxidation of biogenic isoprene contributes globally 47% of glyoxal and 79% of methylglyoxal. The second most important precursors are acetylene (mostly anthropogenic) for glyoxal and acetone (mostly biogenic) for methylglyoxal. Both acetylene and acetone have long lifetimes and provide a source of dicarbonyls in the free troposphere. Atmospheric lifetimes of glyoxal and methylglyoxal in the model are 2.9 h and 1.6 h, respectively, mostly determined by photolysis. Simulated dicarbonyl concentrations in continental surface air at northern midlatitudes are in the range 10–100 ppt, consistent with in situ measurements. On a global scale, the highest concentrations are over biomass burning regions, in agreement with glyoxal column observations from the SCIAMACHY satellite instrument. SCIAMACHY and a few ship cruises also suggest a large marine source of dicarbonyls missing from our model. The global source of SOA from the irreversible uptake of dicarbonyls in GEOS-Chem is 11 Tg C a−1, including 2.6 Tg C a−1 from glyoxal and 8 Tg C a−1 from methylglyoxal; 90% of this source takes place in clouds. The magnitude of the global SOA source from dicarbonyls is comparable to that computed in GEOS-Chem from the standard mechanism involving reversible partitioning of semivolatile products from the oxidation of monoterpenes, sesquiterpenes, isoprene, and aromatics.
578 citations
••
TL;DR: In this paper, the Chen and Teng bond strength model is combined with a simple section analysis for predicting the strength of beams and slabs which fail by intermediate crack-induced debonding.
578 citations
••
TL;DR: It can be concluded that the observed elimination of fluoroquinolones in the STPs was due to their sorption to the sludge, but not biodegradation, and the occurrence and elimination of eight selected antibiotics mainly for human use were investigated at four sewage treatment plants in the Pearl River Delta.
577 citations
••
TL;DR: In this article, the fabrication conditions significantly influence the electron paramagnetic resonance (EPR) and photoluminescence excitation (PLE) spectra obtained, and it is found that green PL emission can be suppressed by coating the nanostructures with a surfactant for all fabrication conditions.
Abstract: ZnO tetrapod nanostructures have been prepared by the evaporation of Zn in air (no flow), dry and humid argon flow, and dry and humid nitrogen flow. Their properties have been investigated using scanning electron microscopy (SEM), X-ray diffraction (XRD), photoluminescence (PL) and photoluminescence excitation (PLE) spectroscopies (at different temperatures), and electron paramagnetic resonance (EPR) spectroscopy at –160 °C and room temperature. It is found that the fabrication conditions significantly influence the EPR and PL spectra obtained. While a g = 1.96 EPR signal is present in some of the samples, green PL emission can be observed from all the samples. Therefore, the green emission in our samples does not originate from the commonly assumed transition between a singly charged oxygen vacancy and a photoexcited hole [K. Vanheusden, C. H. Seager, W. L. Warren, D. R. Tallant, J. A. Voigt, Appl. Phys. Lett. 1996, 68, 403]. However, the green emission can be suppressed by coating the nanostructures with a surfactant for all fabrication conditions, which indicates that this emission originates from surface defects.
575 citations
Authors
Showing all 30115 results
Name | H-index | Papers | Citations |
---|---|---|---|
Jing Wang | 184 | 4046 | 202769 |
Xiang Zhang | 154 | 1733 | 117576 |
Wei Zheng | 151 | 1929 | 120209 |
Rui Zhang | 151 | 2625 | 107917 |
Jian Yang | 142 | 1818 | 111166 |
Joseph Lau | 140 | 1048 | 99305 |
Yu Huang | 136 | 1492 | 89209 |
Dacheng Tao | 133 | 1362 | 68263 |
Chuan He | 130 | 584 | 66438 |
Lei Zhang | 130 | 2312 | 86950 |
Ming-Hsuan Yang | 127 | 635 | 75091 |
Chao Zhang | 127 | 3119 | 84711 |
Yuri S. Kivshar | 126 | 1845 | 79415 |
Bin Wang | 126 | 2226 | 74364 |
Chi-Ming Che | 121 | 1305 | 62800 |