Institution
Nanjing University of Information Science and Technology
Education•Nanjing, China•
About: Nanjing University of Information Science and Technology is a education organization based out in Nanjing, China. It is known for research contribution in the topics: Precipitation & Aerosol. The organization has 14129 authors who have published 17985 publications receiving 267578 citations. The organization is also known as: Nan Xin Da.
Papers published on a yearly basis
Papers
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TL;DR: The PVO embedding is extended into a 2D form by integrating the pairwise prediction- error expansion, and a reversible 2D mapping adapted to the special distribution of prediction-error pairs is proposed.
86 citations
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TL;DR: China has been suffering high levels of fine particulate matter (PM2.5), and residential and industrial emissions are the top two sources, with a combined contribution of 40-50% in most provinces, with higher contributions in southern provinces such as Yunnan, Hainan and Taiwan.
86 citations
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TL;DR: The results show that the multi-frequency BDS observations will greatly improve the PPP performances and theoretical comparison of the models, positioning performances, precise time and frequency transfer, ZTD, inter-frequency bias (IFB), and differential code bias (DCB) are presented and evaluated.
Abstract: Nowadays, China BeiDou Navigation Satellite System (BDS) has been developed well and provided global services with highly precise positioning, navigation and timing (PNT) as well as unique short-message communication, particularly global system (BDS-3) with higher precision multi-frequency signals. The precise point positioning (PPP) can provide the precise position, receiver clock, and zenith tropospheric delay (ZTD) with a stand-alone receiver compared to the traditional double differenced relative positioning mode, which has been widely used in PNT, geodesy, meteorology and so on. However, it has a lot of challenges for multi-frequency BDS PPP with different strategies and more unknown parameters. In this paper, the detailed PPP models using the single-, dual-, triple-, and quad-frequency BDS observations are presented and evaluated. Firstly, BDS system and PPP method are introduced. Secondly, the stochastic models of time delay bias in BDS-2/BDS-3 PPP including the neglection, random constant, random walk and white noise are presented. Then, three single-frequency, four dual-frequency, four triple-frequency and four quad-frequency BDS PPP models are provided. Finally, the BDS PPP models progress and performances including theoretical comparison of the models, positioning performances, precise time and frequency transfer, ZTD, inter-frequency bias (IFB) and differential code bias (DCB) are presented and evaluated as well as future challenges. The results show that the multi-frequency BDS observations will greatly improve the PPP performances.
86 citations
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TL;DR: In this paper, the authors provided source attribution and characterization of black carbon (BC) in Beijing's urban environment during the joint UK-China APHH (Air Pollution and Humanhealth) project, in both winter (November-December 2016) and summer (May-June 2017).
Abstract: . Black carbon (BC) is known to have major impacts on both human health and
climate. The populated megacity represents the most complex anthropogenic BC
emissions where the sources and related impacts are very uncertain. This
study provides source attribution and characterization of BC in the Beijing
urban environment during the joint UK–China APHH (Air Pollution and Human
Health) project, in both winter (November–December 2016) and summer
(May–June 2017). The size-resolved mixing state of BC-containing particles was
characterized by a single-particle soot photometer (SP2) and their mass
spectra was measured by a soot particle aerosol mass spectrometer (SP-AMS). The
refractory BC (rBC) mass loading was around a factor of 2 higher in winter
relative to summer, and more variable coatings were present, likely as a
result of additional surface emissions from the residential sector and
favourable condensation in the cold season. The characteristics of the BC were
relatively independent of air mass direction in summer, whereas in winter
air masses from the Northern Plateau were considerably cleaner and contained
less-coated and smaller BC, but the BC from the Southern Plateau had the
largest core size and coatings. We compare two online source apportionment methods using simultaneous
measurements made by the SP2, which measures physical properties of BC, and
the chemical approach using the positive matrix factorization (PMF) of mass
spectra from the SP-AMS for the first time. A method is proposed to isolate
the BC from the transportation sector using a mode of small BC particles
(core diameter Dc µ m and coating thickness ct 50 nm).
This mode of BC highly correlated with NOx concentration in both
seasons ( ∼14 ng m −3 BC ppb −1 NOx ) and
corresponded with the morning traffic rush hour, contributing about 30 %
and 40 % of the total rBC mass (35 % and 55 % in number) in winter and
summer respectively. The BC from coal burning or biomass burning was
characterized by moderate coatings (ct = 50–200 nm) contributing
∼20 %–25 % of rBC mass. Large uncoated BC particles
( Dc>0.18 µ m and ct 50 nm) were more likely to be
contributed by coal combustion, as these particles were not present in urban
London. This mode was present in Beijing in both winter ( ∼30 %–40 %
rBC mass) and summer ( ∼40 % rBC mass) but may be
dominated by the residential and industrial sector respectively. The
contribution of BC thickly coated with secondary species (ct > 200 nm)
to the total rBC mass increased with pollution level in winter but
was minor in summer. These large BC particles importantly enhanced the absorption
efficiency at high pollution levels – in winter when PM 1 > 100 µ g m −3
or BC > 2 µ g m −3 , the absorption
efficiency of BC increased by 25 %–70 %. The reduction of emissions of these
large BC particles and the precursors of the associated secondary coating
will be an effective way of mitigating the heating effect of BC in urban
environments.
86 citations
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TL;DR: A balanced VM scheduling method is proposed accordingly to determine which VMs and where should be migrated, aiming at both reducing energy consumption and mitigating performance degradation, and results demonstrate the effectiveness and efficiency of the method.
86 citations
Authors
Showing all 14448 results
Name | H-index | Papers | Citations |
---|---|---|---|
Ashok Kumar | 151 | 5654 | 164086 |
Lei Zhang | 135 | 2240 | 99365 |
Bin Wang | 126 | 2226 | 74364 |
Shuicheng Yan | 123 | 810 | 66192 |
Zeshui Xu | 113 | 752 | 48543 |
Xiaoming Li | 113 | 1932 | 72445 |
Qiang Yang | 112 | 1117 | 71540 |
Yan Zhang | 107 | 2410 | 57758 |
Fei Wang | 107 | 1824 | 53587 |
Yongfa Zhu | 105 | 355 | 33765 |
James C. McWilliams | 104 | 535 | 47577 |
Zhi-Hua Zhou | 102 | 626 | 52850 |
Tao Li | 102 | 2483 | 60947 |
Lei Liu | 98 | 2041 | 51163 |
Jian Feng Ma | 97 | 305 | 32310 |