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Elastic_HH: Tailored Elastic for Finding Heavy Hitters [article]

Xilai Liu, Bingqing Liu, Tong Yang, Gaogang Xie
2019 arXiv   pre-print
Finding heavy hitters has been of vital importance in network measurement. Among all the recent works in finding heavy hitters, the Elastic sketch achieves the highest accuracy and fastest speed. However, we find that there is still room for improvement of the Elastic sketch in finding heavy hitters. In this paper, we propose a tailored Elastic to enhance the sketch only for finding heavy hitters at the cost of losing the generality of Elastic. To tailor Elastic, we abandon the light part, and
more » ... mprove the eviction strategy. Our experimental results show that compared with the standard Elastic, our tailored Elastic reduces the error rate to 5.7~8.1 times and increases the speed to 2.5 times. All the related source codes and datasets are available at Github.
arXiv:1909.02203v2 fatcat:d2jo5742qvd5jjqjtsychjezyi

Identification of groundwater nitrate pollution sources in agricultural area using PCA and SIAR methods

Ruyu Yuan, Tianyuan Zheng, Xilai Zheng, Dongsheng Liu, Jia Xin, Lu Yu, Guanqun Liu
2020 Episodes  
Xilai Zheng is a Professer of Ocean University of China. He has published over 200 research papers in international and Chinese journals.  ...  Due to the effects of Guanqun Liu is a Professer of Ocean University of China.  ... 
doi:10.18814/epiiugs/2020/020047 fatcat:gksk23hxz5afxokwi64a2bfryi

A Novel Epidemic Model Base on Pulse Charging in Wireless Rechargeable Sensor Networks

Guiyun Liu, Xiaokai Su, Fenghuo Hong, Xiaojing Zhong, Zhongwei Liang, Xilai Wu, Ziyi Huang
2022 Entropy  
Liu et al.  ... 
doi:10.3390/e24020302 pmid:35205596 pmcid:PMC8870854 fatcat:xxep7d57cjejzculx7xczfsvja

Modelling and Analysis of the Epidemic Model under Pulse Charging in Wireless Rechargeable Sensor Networks

Guiyun Liu, Ziyi Huang, Xilai Wu, Zhongwei Liang, Fenghuo Hong, Xiaokai Su
2021 Entropy  
Similarly, Liu et al. proposed an optimal control scheme based on the novel epidemic model (SILS) [15] , and Cao et al. obtained the optimal control variables of immunization ratio and recovery ratio  ... 
doi:10.3390/e23080927 fatcat:27plvat5tjhc7du2k3ndy5rj7u

Efficiently and Globally Solving Joint Beamforming and Compression Problem in the Cooperative Cellular Network via Lagrangian Duality [article]

Xilai Fan, Ya-Feng Liu, Liang Liu
2022 arXiv   pre-print
Consider the joint beamforming and quantization problem in the cooperative cellular network, where multiple relay-like base stations (BSs) connected to the central processor (CP) via rate-limited fronthaul links cooperatively serve the users. This problem can be formulated as the minimization of the total transmit power, subject to all users' signal-to-interference-plus-noise-ratio (SINR) constraints and all relay-like BSs' fronthaul rate constraints. In this paper, we first show that there is
more » ... o duality gap between the considered problem and its Lagrangian dual by showing the tightness of the semidefinite relaxation (SDR) of the considered problem. Then we propose an efficient algorithm based on Lagrangian duality for solving the considered problem. The proposed algorithm judiciously exploits the special structure of the Karush-Kuhn-Tucker (KKT) conditions of the considered problem and finds the solution that satisfies the KKT conditions via two fixed-point iterations. The proposed algorithm is highly efficient (as evaluating the functions in both fixed-point iterations are computationally cheap) and is guaranteed to find the global solution of the problem. Simulation results show the efficiency and the correctness of the proposed algorithm.
arXiv:2110.05085v2 fatcat:b3uh7u6kvnguvoaf6peapy4c24

Screening of Heavy Metal Tolerant Microbes in Sludge and Removal Capability of Lead

Qianqian Wu, Guanqun Liu, Xilai Zheng, Jiaguo Ren
2015 Journal of Residuals Science and Technology  
The sludge in solid waste dismantling area is often seriously polluted by heavy metals, while some microbes are resisting to heavy metal pollutants due to their life activities such as gene mutations, secretion change and physiology adjustment. This paper identifies two kinds of microorganisms, namely Penicillium citrinum and Aspergillus niger, which can resist heavy metals in the sludge in solid waste dismantling area. By discussing the removal capacity of these two microorganisms on Pb 2+
more » ... r different conditions of pH value, microbial quantity and initial concentration. Results show that these factors have great influence on adsorption of Pb 2+ , when the initial concentration is 30 mg/L and the bacterium fluid volume is 2 ml. The removal rate is the highest under such condition. The comparative experiments show that removal capacity of Penicillium citrinum is better than Aspergillus niger. Heavy metal ions can be effectively removed by both types of microorganisms.
doi:10.12783/issn.1544-8053/12/2/7 fatcat:bjuyjl34fzcazo3sfb4tqgk7hy

Short-term prediction of groundwater level using improved random forest regression with a combination of random features

Xuanhui Wang, Tailian Liu, Xilai Zheng, Hui Peng, Jia Xin, Bo Zhang
2018 Applied Water Science  
To solve the problem where by the available on-site input data are too scarce to predict the level of groundwater, this paper proposes an algorithm to make this prediction called the canonical correlation forest algorithm with a combination of random features. To assess the effectiveness of the proposed algorithm, groundwater levels and meteorological data for the Daguhe River groundwater source field, in Qingdao, China, were used. First, the results of a comparison among three regressors
more » ... that the proposed algorithm is superior in terms of forecasting variations in groundwater level. Second, the results of experiments were used to show the comparative superiority of the proposed method in terms of training time and complexity of parameter optimization. Third, using the proposed algorithm, the highest prediction accuracy was achieved by employing precipitation P(t − 2), temperature T(t), and groundwater level H(t) as the best time lag. This improved random forest regression model yielded higher accuracy in forecasting the variation in groundwater level. The proposed algorithm can also be applied to cases involving low-dimensional data.
doi:10.1007/s13201-018-0742-6 fatcat:6t2bpxo765gbpgg7jfb35etam4

A Flagellin-Derived Toll-Like Receptor 5 Agonist Stimulates Cytotoxic Lymphocyte-Mediated Tumor Immunity

Nicholas D. Leigh, Guanglin Bian, Xilai Ding, Hong Liu, Semra Aygun-Sunar, Lyudmila G. Burdelya, Andrei V. Gudkov, Xuefang Cao, Ciriaco A. Piccirillo
2014 PLoS ONE  
Toll-like receptor (TLR) mediated recognition of pathogen associated molecular patterns allows the immune system to rapidly respond to a pathogenic insult. The "danger context" elicited by TLR agonists allows an initially non-immunogenic antigen to become immunogenic. This ability to alter environment is highly relevant in tumor immunity, since it is inherently difficult for the immune system to recognize host-derived tumors as immunogenic. However, immune cells may have encountered certain TLR
more » ... ligands associated with tumor development, yet the endogenous stimulation is typically not sufficient to induce spontaneous tumor rejection. Of special interest are TLR5 agonists, because there are no endogenous ligands that bind TLR5. CBLB502 is a pharmacologically optimized TLR5 agonist derived from Salmonella enterica flagellin. We examined the effect of CBLB502 on tumor immunity using two syngeneic lymphoma models, both of which do not express TLR5, and thus do not directly respond to CBLB502. Upon challenge with the T-cell lymphoma RMAS, CBLB502 treatment after tumor inoculation protects C57BL/6 mice from death caused by tumor growth. This protective effect is both natural killer (NK) cell-and perforin-dependent. In addition, CBLB502 stimulates clearance of the B-cell lymphoma A20 in BALB/c mice in a CD8 + T cell-dependent fashion. Analysis on the cellular level via ImageStream flow cytometry reveals that CD11b + and CD11c + cells, but neither NK nor T cells, directly respond to CBLB502 as determined by NFkB nuclear translocation. Our findings demonstrate that CBLB502 stimulates a robust antitumor response by directly activating TLR5expressing accessory immune cells, which in turn activate cytotoxic lymphocytes.
doi:10.1371/journal.pone.0085587 pmid:24454895 pmcid:PMC3891810 fatcat:nzhkuq4hxneh5h4zk5xylpulty

Deep removal of sulfur from real diesel by catalytic oxidation with halogen-free ionic liquid

Dan Liu, Jianzhou Gui, Yong-Ki Park, Shuang Yang, Yuhuan Gao, Xilai Peng, Zhaolin Sun
2011 Korean Journal of Chemical Engineering  
doi:10.1007/s11814-011-0135-0 fatcat:62uz5zcd5bfudc4gx3mz3sbb2m

Confining sulfur in intact freestanding scaffold of yolk-shell nanofibers with high sulfur content for lithium-sulfur batteries

Xilai Zhang, Peng Zhang, Shijie Zhang, Yongshang Zhang, Ruohan Hou, Kangli Liu, Fujun Miao, Guosheng Shao
2020 Journal of Energy Chemistry  
Nanostructure design holds great potential in fabricating sulfur electrodes that host a high sulfur loading and still attain high electrochemical utilization for the developing of high-energy-density lithium-sulfur (Li-S) batteries. In this contribution, we introduce the yolk-shell structure into a freestanding carbon nanofibers film and construct a complete hollow yolk-shell TiO 2 /carbon nanofibers@void@TiN@carbon (TiO 2 -CNFs@void@TiN@C) composite. With inherent double conductive network and
more » ... strong adsorption capability for polysulfides, the TiO 2 -CNFs@void@TiN@C composite can not only provide sufficient electrical contact for the insulating sulfur, but also effectively entrap polysulfides for prolonged cycle life. As a result, an excellent capacity retention ratio of 60.9% after 10 0 0 cycles at 1 C as well as a high capacity of 688.5 mAh g −1 at 5 C rate is accomplished with the cells employing TiO 2 -CNFs@void@TiN@C as a cathode substrate for sulfur. Moreover, the TiO 2 -CNFs@void@TiN@C composite, with a high S mass loading of 9.5 mg cm −2 , delivers a superb areal capacity of 8.2 mAh cm −2 .
doi:10.1016/j.jechem.2020.03.065 fatcat:bneeu7vz2razrceat2cxid7rsy

Impacts of the Degraded Alpine Swamp Meadow on Tensile Strength of Riverbank: A Case Study of the Upper Yellow River

Haili Zhu, Peng Gao, Zhiwei Li, Jiangtao Fu, Guorong Li, Yabin Liu, Xilai Li, Xiasong Hu
2020 Water  
In the meandering riverbank of the Upper Yellow River (UYR), the native alpine swamp meadow (AS) has continuously degenerated into an alpine meadow (AM) due to climate change and intensified grazing. Its implication on river morphology is still not well known. This study examined this effect by in situ measurings of (1) physical properties of roots and their distribution in the soil-root mixture of the upper bank layer, and (2) the tensile strength in terms of excavating tests for triggering
more » ... tilever collapses of AS and AM riverbanks. The results showed that the root number in AS was significantly greater than that in AM, though the root distribution in both was similar. Also, the average tensile strength of individual roots in AS was 31,310 kPa, while that in AM was only 16,155 kPa. For the soil-root mixture, it decreased from 67.39 to 21.96 kPa. The weakened mechanical property was mainly ascribed to the lessened root number and the simpler root structure in the soil-root mixture of AM that reduces its ability to resist the external force. These findings confirmed that healthy AS can enhance bank stability and delay the development of tensile cracks in the riverbank of the meandering rivers in the UYR.
doi:10.3390/w12092348 fatcat:4jk3bxzf3fabzck3hb56cywmc4

In situ sulfur-doped graphene network as efficient metal-free electrocatalyst for polysulfides redox reactions in lithium-sulfur batteries

Shijie Zhang, Peng Zhang, Ruohan Hou, Bin Li, Yongshang Zhang, Kangli Liu, Xilai Zhang, Guosheng Shao
2020 Journal of Energy Chemistry  
The major challenge for realistic application of Li-S batteries lies in the great difficulty in breaking through the obstacles of the sluggish kinetics and polysulfides shuttle of the sulfur cathode at high sulfur loading for continuously high sulfur utilization during prolonged charge-discharge cycles. Here we demonstrate that large percentage of sulfur can be effectively incorporated within a three-dimensional (3D) nanofiber network of high quality graphene from chemical vapor deposition
more » ... , through a simple ball-milling process. While high quality graphene network provided continuous and durable channels to enable efficient transport of lithium ions and electrons, the in-situ sulfur doping from the alloying effect of ball milling facilitated desirable affinity with entire sulfur species to prevent sulfur loss and highly active sites to propel sulfur redox reactions over cycling. This resulted in remarkable rate-performance and excellent cycling stability, together with large areal capacity at very high sulfur mass loading (Specific capacity over 666 mAh g −1 after 300 cycles at 0.5 C, and areal capacity above 5.2 mAh cm −2 at 0.2 C at sulfur loading of 8.0 mg cm −2 and electrolyte/sulfur (E/S) ratio of 8 μL mg −1 ; and high reversible areal capacities of 13.1 mAh cm −2 at a sulfur load of 15 mg cm −2 and E/S of 5 μL mg −1 ).
doi:10.1016/j.jechem.2020.01.033 fatcat:vdby2urx2be3zary6kj4tntlpy

Synthesis of PAN with adjustable molecular weight and low polydispersity index (PDI) value via reverse atom transfer radical polymerization

Shuang Li, Yazhen Wang, Liqun Ma, Xueze Zhang, Shaobo Dong, Li Liu, Xilai Zhou, Chenglong Wang, Zhen Shi
2019 Designed Monomers and Polymers  
The reverse atom transfer radical polymerization (RATRP) of acrylonitrile (AN) was carried out in N, N-dimethylformamide (DMF) with AIBN as initiator, FeCl3•6H2O/triphenylphosphine (PPh3) and FeCl3•6H2O/pentamethyldle-thylenetrlamlne (PMDETA) as catalytic systems, respectively. Effect of reaction time and initiator concentration on polymerization rate, molecular weight and molecular weight distribution were investigated in detail. The Fourier transform infrared spectrometer (FTIR) and 1H
more » ... magnetic resonance spectroscopy (1HNMR) were employed to analyze the chain end of the PAN. Gel permeation chromatography (GPC) was applied to measure the molecular weight and polydispersity index (PDI) of PAN. The polymerization demonstrated a typical pseudo first-order kinetics characteristics as evidenced by the number-average molecular weights (Mn) increasing linearly with monomer conversion; the Mn decreasing with the increasing of the initiator concentration. Meanwhile, the low PDI value (<1.2) indicated the controllability of polymerization.
doi:10.1080/15685551.2019.1678557 pmid:31700503 pmcid:PMC6830196 fatcat:ibatqll7szfffhpxcur2essu74

Cross-Regulation of Two Type I Interferon Signaling Pathways in Plasmacytoid Dendritic Cells Controls Anti-malaria Immunity and Host Mortality

Xiao Yu, Baowei Cai, Mingjun Wang, Peng Tan, Xilai Ding, Jian Wu, Jian Li, Qingtian Li, Pinghua Liu, Changsheng Xing, Helen Y. Wang, Xin-zhuan Su (+1 others)
2016 Immunity  
trigger robust MyD88-dependent IFN regulatory factor (IRF) 7 transcription factor-mediated type I IFN signaling and produce large amounts of IFN-a and IFN-b (IFN-a/b) in response to viral infection (Liu  ...  -MyD88-IRF7 molecules constitute key components of MyD88-dependent type I IFN signaling, which has been shown to operate in only pDC for production of large amounts of IFN-a/b after viral infection (Liu  ... 
doi:10.1016/j.immuni.2016.10.001 pmid:27793594 pmcid:PMC7128466 fatcat:tggk4bi63bgz7oqnbficqsmwvu

Elucidating the Pollution Sources and Groundwater Evolution in Typical Seawater Intrusion Areas Using Hydrochemical and Environmental Stable Isotope Technique: A Case Study for Shandong Province, China

Guangquan Chen, Guiyao Xiong, Jin Lin, Xingyong Xu, Hongjun Yu, Wenquan Liu, Tengfei Fu, Qiao Su, Yancheng Wang, Yunfeng Dai, Imran Ali, Xilai Zheng (+2 others)
2021 Lithosphere  
Seawater intrusion has a serious impact on industry, agriculture, and people's daily life. Thus, the present study was designed to elucidate the pollution sources and groundwater evolution in typical intrusion areas of Shandong Province by hydrochemistry and environmental isotope techniques. The water samples were collected to analyze the groundwater evolution under different intrusion, and groundwater evolution in the south of Laizhou Bay from 2005 to 2019. The findings indicated that the
more » ... dwater level dropping funnel caused by overexploitation was the direct causation of seawater intrusion in the three typical intruded areas. The groundwater evolution paths demonstrated that the groundwater in the south of Laizhou Bay had the fastest evolution rate and the highest degree of evolution, followed by the Dagu River Basin. The groundwater evolution extent and fitting of mixing lines indicated that the groundwater in the south of Laizhou Bay, Longkou, and Dagu River Basin was dominated by palaeosaltwater intrusion, modern seawater intrusion, and sea-saltwater mixed intrusion, respectively. Palaeosaltwater mixing produces a more severe salinization effect compared to seawater mixing. Meanwhile, the isotopes are gradually enriched with the deepening of intrusion, while the decrease of isotopes is delayed compared with the saltwater retreat. This is caused by that the stable isotopes enriched in the aquiclude due to the chemical permeation effect will be released into the aquifer after the salinity attenuates in the aquifer. The palaeosaltwater intrusion caused by anthropogenic activities has promoted serious fluorine pollution in the south of Laizhou Bay, while the groundwater nitrate pollution in Longkou was the most serious, followed by the Dagu River Basin due to high-density agricultural and domestic activity.
doi:10.2113/2021/4227303 fatcat:65s4studqzatdhwdtrd64rlynm
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