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Local galaxies with compact cores as the possible descendants of massive compact quiescent galaxies at high redshift

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Research in Astronomy and Astrophysics 2020年第7期20卷 139-148页

作者： Ying Gao lu-lu fan Shandong Key Laboratory of Optical Astronomy and Solar-Terrestrial Environment School of Space Science and PhysicsInstitute of Space SciencesShandong UniversityWeihai 264209China CAS Key Laboratory for Research in Galaxies and Cosmology Department of AstronomyUniversity of Science and Technology of ChinaHefei 230026China School of Astronomy and Space Sciences University of Science and Technology of ChinaHefei 230026China

In order to test a possible evolutionary scenario of high-z compact quiescent galaxies(cQGs)that they can survive as local compact cores embedded in local massive galaxies with different morphology classes, we explore the star formation histories of local compact cores according to their spectral *** build a sample of 182 massive galaxies with compact cores(M*,core> 10^10.6 M⊙) at 0.02 ≤ z ≤ 0.06 from SDSS DR7 spectroscopic catalogue. The STARLIGHT package is used to analyze the median stacked spectra and derive the stellar ages and metallicities. Our main results show that local compact cores have the average age of about 12.1 ± 0.6 Gyr, indicating their early formation at z > 3, which is consistent with the formation redshifts of cQGs at 1 lutionary paths for high-z cQGs: most of them(> 80%)will evolve into local massive early-type galaxies according to dry minor merger, while some of them(~ 15%) will build substantial stellar/gas discs according to the late-time gas accretion and sustaining star formation, and finally grow up into spiral galaxies.

关键词： galaxies:bulges galaxies:evolution galaxies:formation galaxies:stellar content galaxies:structure

Distributed bias-compensated normalized least-mean squares algorithms with noisy input

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Science China(Information Sciences) 2018年第11期61卷 193-207页

作者： lu fan Lijuan JIA Ran TAO Yue WANG School of Information and Electronics Beijing Institute of Technology

In this paper, we study the problem of distributed normalized least-mean squares(NLMS) estimation over multi-agent networks, where all nodes collaborate to estimate a common parameter of *** consider the situations that all nodes in the network are corrupted by both input and output noise. This yields into biased estimates by the distributed NLMS algorithms. In our analysis, we take all the noise into consideration and prove that the bias is dependent on the input noise variance. Therefore, we propose a bias compensation method to remove the noise-induced bias from the estimated results. In our development, we first assume that the variances of the input noise are known a priori and develop a series of distributed-based bias-compensated NLMS(BCNLMS) methods. Under various practical scenarios, the input noise variance is usually unknown a priori, therefore it is necessary to first estimate for its value before bias removal. Thus, we develop a real-time estimation method for the input noise variance, which overcomes the unknown property of this noise. Moreover, we perform some main analysis results of the proposed distributed BCNLMS algorithms. Furthermore, we illustrate the performance of the proposed distributed bias compensation method via graphical simulation results.

关键词： distributed parameter estimation normalized least-mean squares bias-compensated algorithms

Two-Variable Hermite Function as Quantum Entanglement of Harmonic Oscillator＇s Wave Functions

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Communications in Theoretical Physics 2007年第6期47卷 1024-1028页

作者： lu Hai-Liang fan Hong-Yi Department of Physics Shanghai Jiao Tong University Shanghai 200030 China

We reveal that the two-variable Hermite function hm,n, which is the generalized Bargmann representation of the two-mode Fock state, involves quantum entanglement of harmonic oscillator＇s wave functions. The Schmidt decomposition of hm,n is derived. It also turns out that hm,n can be generated by windowed Fourier transform of the single-variable Hermite functions. As an application, the wave function of the two-variable Hermite polynomial state S（γ）Hm,n （μa1^＋, μa2^＋│00〉, which is the minimum uncertainty state for sum squeezing, in （ η│representation is calculated.

关键词： two-variable Hermite function quantum entanglement Bargmann representation Schmidt decomposition

Example-based super-resolution for single-image analysis from the Chang'e-1 Mission

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Research in Astronomy and Astrophysics 2016年第11期16卷 57-60页

作者： fan-lu Wu Xiang-Jun Wang State Key Laboratory of Precision Measuring Technology and Instruments Tianjin University

Due to the low spatial resolution of images taken from the Chang＇e-1 （CE-I） orbiter, the details of the lunar surface are blurred and lost. Considering the limited spatial resolution of image data obtained by a CCD camera on CE-1, an example-based super-resolution （SR） algorithm is employed to obtain high- resolution （HR） images. SR reconstruction is important for the application of image data to increase the resolution of images. In this article, a novel example-based algorithm is proposed to implement SR reconstruction by single-image analysis, and the computational cost is reduced compared to other example-based SR methods. The results show that this method can enhance the resolution of images using SR and recover detailed information about the lunar surface. Thus it can be used for surveying HR terrain and geological features. Moreover, the algorithm is significant for the HR processing of remotely sensed images obtained by other imaging systems.

关键词： Moon - methods: data analysis - techniques: image processing

Engineering Deinococcus radiodurans into biosensor to monitor radioactivity and genotoxicity in environment

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Chinese Science Bulletin 2008年第11期53卷 1675-1681页

作者： GAO GuanJun fan lu lu HuiMing HUA YueJin Institute of Nuclear-Agricultural Sciences Key Laboratory of Chinese Ministry of Agriculture for Nuclear-Agricultural Sciences Zhejiang University Hangzhou 310029 China

Based on a genetically modified radioresistant bacteria Deinococcus radiodurans, we constructed a real time whole cell biosensor to monitor radioactivity and genotoxicity in highly radioactive environ-ment. The enhanced green fluorescence protein (eGFP) was fused to the promoter of the crucial DNA damage-inducible recA gene from D. radiodurans, and the consequent DNA fragment (PrecA-egfp) car-ried by plasmid was introduced into D. radiodurans R1 strain to obtain the biosensor strain DRG300. This engineered strain can express eGFP protein and generate fluorescence in induction of the recA gene promoter. Based on the correlation between fluorescence intensity and protein expression level in live D. radiodurans cells, we discovered that the fluorescence induction of strain DRG300 responds in a remarkable dose-dependent manner when treated with DNA damage sources such as gamma radiation and mitomycin C. It is encouraging to find the widely detective range and high sensitivity of this re-constructed strain comparing with other whole cell biosensors in former reports. These results suggest that the strain DRG300 is a potential whole cell biosensor to construct a detective system to monitor the biological hazards of radioactive and toxic pollutants in environment in real time.

关键词：生物传感器环境监测放射能环境污染

Multi-Task Learning for Food Identification and Analysis with Deep Convolutional Neural Networks

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Journal of Computer Science & Technology 2016年第3期31卷 489-500页

作者： Xi-Jin Zhang Yi-fan lu Song-Hai Zhang Department of Computer Science and Technology Tsinghua University Beijing 100084 China

In this paper, we proposed a multi-task system that can identify dish types, food ingredients, and cooking methods from food images with deep convolutional neural networks. We built up a dataset of 360 classes of different foods with at least 500 images for each class. To reduce the noises of the data, which was collected from the Internet, outlier images were detected and eliminated through a one-class SVM trained with deep convolutional features. We simultaneously trained a dish identifier, a cooking method recognizer, and a multi-label ingredient detector. They share a few low-level layers in the deep network architecture. The proposed framework shows higher accuracy than traditional method with handcrafted features, and the cooking method recognizer and ingredient detector can be applied to dishes which are not included in the training dataset to provide reference information for users.

关键词： multi-task learning convolutional neural network food recognition machine learning

Bioaerosolization behavior along sewage sludge biostabilization

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Frontiers of Environmental Science & Engineering 2021年第3期15卷 151-164页

作者： fan lu Tianyu Hu Shunyan Wei Liming Shao Pinjing He State Key Laboratory of Pollution Control and Source Reuse Tongji UniversityShanghai 200092China Shanghai Institute of Pollution Control and Ecological Security Shanghai 200092China Institute of Waste Treatment and Reclamation Tongji UniversityShanghai 200092China

Biostabilization is a cost-effective method for the beneficial utilization of sewage ***,during the operation of sludge biostabilization,some microbial species could be released into the atmospheric environment from the solid-phase of sludge easily and present a high risk to human *** study aimed to evaluate the risk of bioaerosol during sludge *** found a total of nine bacterial phyla,one archaeal phylum,and two fungal phyla in the bioaerosol *** them,Proteobacteria,Actinobacteria,Bacteroidetes,and Ascomycota were the dominant *** addition,the bioaerosolization indexes(BI)of prokaryotic phyla and flingal phyla ranged 0-45 and 0-487,*** ilia y Pseudarthrobacter,Pseudomonas,Tremellales spp.,and Fusarium were the preferentially aerosolized microbial genera with maximum bioaerosolization indexes of 19962,10360,1802,3055,and *** bioaerosol concentration during the biostabilization ranged from 160 to 1440 cell/m^(3),and we identified species such as Stenotrophomonas rhizophila and Fusarium graminerum with high bioaerosolization indexes that could be threats to human ***,which belongs to archaeal phyla,had the highest biostabilization index in our *** also found that Pseudarthrobacter was the easiest to aerosolize during the sludge biostabilization process.

关键词： Sludge Composting Bioaerosol Bioaerosolization index High-throughput sequencing 4’,6-diamidino-2-phenylindole(DAPI)

In-situ neutralize methane emission from landfills in loess regions using leachate

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Science China(Technological Sciences) 2021年第7期64卷 1500-1512页

作者： HE PinJing CHEN JunLan SHAO LiMing ZHANG Hua lu fan Institute of Waste Treatment and Reclamation Tongji UniversityShanghai200092China Shanghai Institute of Pollution Control and Ecological Security Shanghai200092China

In loess regions, landfilling is the predominant solid waste disposal and loess is usually used as landfill cover soil. However, the methane(CH_4) bio-oxidation activity of virgin loess is usually below 0.01 μmol/(h g-soil). In this study, we proposed a method to improve CH_4 removal capacity of loess by amelioration with mature landfill leachate, which is in-situ, easily available, and appropriate. The organic matter content of the ameliorated loess increased by 180%, reaching 19.69–24.88 g/kg-soil, with more than 90% being non-leachable. The abundance of type I methane-oxidizing bacteria and methane monooxygenase gene pmoA increased by 5.0 and 79 times, respectively. Consequently, the maximum CH_4 removal rate of ameliorated loess reached 0.74–1.41 μmol/(h g-soil) at 25°C, which was 4-fold higher than that of water-irrigated loess. Besides, the CH_4 removal rate peaked at 10 vt% CH_4 concentration and remained at around 1.4 μmol/(h g-soil) at 15°C–35°C. The column test confirmed that the highest CH_4 removal efficiency was at 30–40 cm below the surface, reaching 26.1%±0.4%, and the 50-cm-thick loess layer irrigated with leachate achieved more than 85% CH_4 removal efficiency. These results could help to realize carbon neutrality in landfill sites of global loess regions.

关键词： methane bio-oxidation leachate irrigation loess improvement landfill cover soil greenhouse gas emission biocover solid waste

Changes in runoff and eco-flow in the Dongjiang River of the Pearl River Basin, China

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Frontiers of Earth Science 2014年第4期8卷 547-557页

作者： Kairong LIN Yanqing LIAN Xiaohong CHEN fan lu Department of Water Resources and Environment Sun Yat-sen University Guangzhou 510275 China Key Laboratory of Water Cycle and Water Security in Southern China of Guangdong High Education Institute Sun Yat-sen University Guangzhou 510275 China Illinois State Water Survey The Prairie Research Institute University of Illinois at Urbana-Champaign IL 61820 USA China Institute of Water Resources and Hydropower Research Department of Water Resources Beijing 100038 China

The Dongjiang River, one of the tributaries of the Pearl River, serves as the critical water source for Guangdong Province and the District of Hong Kong in China. In this study, the change trend and change points of flow at three main gaging stations in the Dongjiang River were analyzed using the nonparametric Mann-Kendall test and Pettitt-Mann-Whitney change-point statistics. Flow regime changes in the Dongjiang River were quantified by using both the Indicators of Hydrologic Alteration （IHA） parameters and eco-statistics, such as ecosurplus and eeodeficit. It was found that the change trend for annual median flow in the Dongjiang River increased over the past 60years, with the major change occurring sometime between 1970 and 1974. IHA analyses showed that the magnitude of monthly flow decreased during the flood period, but increased greatly during the dry period. The median date of the one-day minimum flow moved ahead, and the duration of low pulse for the Dongjiang River was reduced significantly because of reservoir construction and operations. The IHA-based Dundee Hydrological Regime Alteration Method analysis indicated that all three stations have experienced a moderate risk of impact since 1974. The eco-statistical analyses showed that the majority of the flows appeared to be ecosurplus at all three locations after 1974, while flows with less than 30%, or higher exceedance probability, had ecodeficit in the summer flood period due to heavy reservoir operations.

关键词： hydrologic alteration change point analysis,runoff eco-flow