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Efficient Cross-Validation for Semi-Supervised Learning [article]

Yong Liu and Jian Li and Guangjun Wu and Lizhong Ding and Weiping Wang
2019 arXiv   pre-print
Manifold regularization, such as laplacian regularized least squares (LapRLS) and laplacian support vector machine (LapSVM), has been widely used in semi-supervised learning, and its performance greatly depends on the choice of some hyper-parameters. Cross-validation (CV) is the most popular approach for selecting the optimal hyper-parameters, but it has high complexity due to multiple times of learner training. In this paper, we provide a method to approximate the CV for manifold
more » ... based on a notion of robust statistics, called Bouligand influence function (BIF). We first provide a strategy for approximating the CV via the Taylor expansion of BIF. Then, we show how to calculate the BIF for general loss function,and further give the approximate CV criteria for model selection in manifold regularization. The proposed approximate CV for manifold regularization requires training only once, hence can significantly improve the efficiency of traditional CV. Experimental results show that our approximate CV has no statistical discrepancy with the original one, but much smaller time cost.
arXiv:1902.04768v1 fatcat:h2cge7op6zcennf7i3rqqec5pu

Murine exposure to gold nanoparticles during early pregnancy promotes abortion by inhibiting ectodermal differentiation

Hui Yang, Libo Du, Guangjun Wu, Zhenyu Wu, Jeffrey A. Keelan
2018 Molecular Medicine  
Gold nanoparticles (AuNPs) have been widely studied for biomedical applications, although their safety and potential toxicity in pregnancy remains unknown. The aim of this study is to explore the effect of AuNPs maternal exposure at different gestational ages on fetal survival and development, as well as the potential mechanism of AuNPs affecting embryos and fetuses. Methods: Thirty nm polyethylene glycol (PEG)-coated AuNPs (A30) were administered to pregnant mice via intravenous injection (5
more » ... Au/g body weight) over three days at either early or late pregnancy. Fetal abortion rate and morphological development in E16.5 were then detected in detail. The pregnant mice physiological states with A30 exposure were examined by biochemical, histological or imaging methods; and materno-fetal distribution of gold elements was assayed by electron microscopy and mass spectrometry. Murine embryonic stem cells derived embryoid-bodies or neuroectodermal cells were treated with A30 (0.0025 to 0.25 μg Au/mL) to examine A30 effects on expression levels of the germ differentiation marker genes. Tukey's method was used for statistical analysis. Results: Exposure to A30 during early (A30E) but not late (A30L) pregnancy caused a high abortion rate (53.5%), lower fetal survival rate and abnormal decidualization compared with non-exposed counterparts. The developmental damage caused by A30 followed an "all-or-nothing" pattern, as the non-aborted fetuses developed normally and pregnancies maintained normal endocrine values. A30 caused minor impairment of liver and kidney function of A30E but not A30L mice. TEM imaging of fetal tissue sections confirmed the transfer of A30 into fetal brain and live as aggregates. qPCR assays showed A30 suppressed the expression of ectodermal, but not mesodermal and endodermal differentiation markers. Conclusions: These results illustrate that maternal A30 exposure in early pregnant results in A30 transfer into embryonic tissues, inhibiting ectodermal differentiation of embryonic stem cells, leading to abnormal embryonic development and abortion. While exposure to A30 during late pregnancy had little or no impact on dams and fetuses. These findings suggest the safety of biomedical applications employing AuNPs during pregnancy is strongly influenced by fetal maturity and gestational age at exposure and provide the clues for AuNPs safe application period in pregnancy.
doi:10.1186/s10020-018-0061-2 fatcat:lu4qv6qeobavznhx7q3uaspmpi

Multidisciplinary Design Optimization of a Swash-Plate Axial Piston Pump

Guangjun Liu, Zhaocheng Zhou, Xin Qian, Xiaofeng Wu, Weihai Pang
2016 Applied Sciences  
Author Contributions: Guangjun Liu and Xiaofeng Wu designed and implemented the optimization procedure proposed in the paper.  ... 
doi:10.3390/app6120399 fatcat:hlvtbxokavacnibr5hoa4fsolm

A simple synthesis of Ga2O3 and GaN nanocrystals

Erwei Huang, Juxia Li, Guangjun Wu, Weili Dai, Naijia Guan, Landong Li
2017 RSC Advances  
A simple top-down strategy to α-Ga2O3 and GaN nanocrystals is developed and the morphology-dependent optical properties of α-Ga2O3 crystals are established.
doi:10.1039/c7ra10639d fatcat:gy6rf36zzvcvngqvfebt6jwosm

On convergence for sequences of pairwise negatively quadrant dependent random variables

Yongfeng Wu, Guangjun Shen
2014 Applications of Mathematics  
The research of Guangjun Shen is supported by the National Natural Science Foundation of China (11271020). then the above result was called the complete moment convergence.  ...  [10] , Li and Yang [9] , Wu and Jiang [18] ), the weak convergence (Meng and Lin [13] , Gan and Chen [5] ), the complete convergence (Wu [16] , Wan [15] , Gan and Chen [4] , Baek et al.  ... 
doi:10.1007/s10492-014-0067-1 fatcat:ja5kedv4srfy3c5pg2fyocfr6y

Improved Wavelet Denoising by Non-convex Sparse Regularization under Double Wavelet Domains

Yongjun Wu, Guangjun Gao, Can Cui
2019 IEEE Access  
YONGJUN WU received the B.S. and M.S. degrees from Central South University, China, in 2013 and 2016, respectively, where he is currently pursuing the Ph.D. degree.  ...  GUANGJUN GAO received the M.S. and Ph.D. degrees from Central South University, China, in 2001 and 2008, respectively, where he is currently a Professor with the School of Traffic and Transportation Engineering  ... 
doi:10.1109/access.2019.2903125 fatcat:v33tbkj7ojcxnbksql6z5maohy

Fabrication of Ta2O5 films on tantalum substrate for efficient photocatalysis

Juxia Li, Weili Dai, Guangjun Wu, Naijia Guan, Landong Li
2015 Catalysis communications  
Ta 2 O 5 films have been successfully fabricated on tantalum substrate via a facile hydrothermal route and characterized by a series of spectroscopic techniques. The morphology of the as-prepared Ta 2 O 5 films showed great impacts on the photocatalytic activity. Without any co-catalysts, the as-prepared Ta 2 O 5 films on tantalum exhibited remarkable photocatalytic activity and recyclability both in the degradation of rhodamine B and in the hydrogen production from water splitting under UV
more » ... diation. © 2015 Elsevier B.V. All rights reserved. Characterization of Ta 2 O 5 films The XRD patterns of samples were recorded on a Bruker D8 ADVANCE powder diffractometer using Cu-K radiation (λ = 0.1542 nm) at a scanning rate of 4°/min in the region of 2θ = 20-60°. The morphology and chemical composition of the as-prepared samples were analyzed by field emission scanning electron microcopy (FE-SEM, Hitachi S-4800). Catalysis Communications 65 (2015) 24-29 ⁎ Corresponding authors.
doi:10.1016/j.catcom.2015.02.006 fatcat:inbpz7ltkfgpxk46vzkwno3f2e

The active commissioning process for a power reactor spent fuel reprocessing pilot plant in China

TianXiang Zhang, Jian Wang, Tao Wu, GuangJun Chen, YongQing Di Wu, FaQuan Ru
2011 Chinese Science Bulletin  
innovative technology for power reactor spent fuel reprocessing had been developed by our country. spent fuel reprocessing, pilot plant, commissioning, recovery rate, purification Citation: Zhang T X, Wang J, Wu  ... 
doi:10.1007/s11434-011-4600-2 fatcat:4j4pexewsfb5pccdwi2e7draqy

Fabrication of WO2.72/RGO nano-composites for enhanced photocatalysis

Bo Ma, Erwei Huang, Guangjun Wu, Weili Dai, Naijia Guan, Landong Li
2017 RSC Advances  
WO2.72/RGO nano-composites exhibit remarkable photocatalytic activity in both oxygen evolution from water splitting and selective oxidation of benzyl alcohol due to the synergetic effects between WO2.72 and RGO.
doi:10.1039/c6ra26416f fatcat:ezmnollyizfgbacf2habtosr2m

Consecutive Interpretation: A Discourse Approach. Towards a Revision of Gile's Effort Model

Guangjun Wu, Kefei Wang
2009 Meta : Journal des traducteurs  
Montréal. Il a pour mission la promotion et la valorisation de la recherche. Érudit offre des services d'édition numérique de documents scientifiques depuis 1998. Note : les règles d'écriture des références bibliographiques peuvent varier selon les différents domaines du savoir. Ce document est protégé par la loi sur le droit d'auteur. L'utilisation des services d'Érudit (y compris la reproduction) est assujettie à sa politique d'utilisation que vous pouvez consulter à l'URI
more » ... it.org/fr/usagers/politique-dutilisation/ Document RÉSUMÉ En situation réelle d'interprétation consécutive, les interprètes professionnels peuvent, à l'occasion, réussir à combler l'écart entre la capacité mémorielle nécessaire et la capacité disponible lorsqu'ils traitent des segments extrêmement longs. L'existence de ces cas exceptionnels implique que le modèle d'efforts de Gile ne peut toujours s'appliquer et qu'il faut le compléter. Le présent article a trois objectifs. Premièrement, il cherche à proposer une solution à ce problème. Deuxièmement, il vise à spécifier les règles de transformation discursive en contexte d'interprétation consécutive. Se fondant sur les propriétés de la mémoire et les caractéristiques de l'interprétation consécutive, nous considérons que chaque segment, qu'il soit court ou long, sera traité en tant que discours, pour laquelle on présume que la transformation résultante est la solution. Troisièmement, il vise à définir un modèle de transformation discursive optimal, qui puisse tout à la fois rendre au maximum le texte source et être réaliste en termes de charge mémorielle. Bien que l'auteur justifie son hypothèse en s'appuyant sur une étude observationnelle, d'autres données expérimentales sont nécessaires pour valider la théorie proposée. ABSTRACT In reality, expert interpreters from time to time do successfully tide over the gap between the capacity required and capacity available in dealing with extraordinarily large segments in consecutive interpretation. These exceptional cases imply that Gile's Effort Model does not always hold and requires to be supplemented. This paper attempts to: 1) advance a solution to the dilemma that, in processing large segments in consecutive interpreting, the working memory capacity available is more often than not smaller than the capacity required, hence supplementing Gile's Effort Model; 2) specify the rules of discourse transformation in consecutive interpretation; based upon the features of memory and consecutive interpretation, we deem that each segment, be it large or small, shall be processed as a discourse, the transformation of which is presumed to be the said solution; 3) and subsequently identify the optimal discourse transformation model, which is both capable of embodying the source text to the largest extent possible and achievable in terms of memory load. In addition, the author, through an observational study, justified the hypothesis. The validity of this theory, however, still requires further experimental evidence. MOTS-CLÉS/KEY WORDS modèle d'efforts, capacité exigée, capacité disponible, transformation du discours, interprétation consécutive Effort Model, capacity required, capacity available, discourse transformation, consecutive interpretation 402 Meta, LIV, 3, 2009
doi:10.7202/038305ar fatcat:zgxvfpdj5fd2he2f77vo5x7r6q

A Effective Truth Discovery Algorithm with Multi-source Sparse Data [chapter]

Jiyuan Zhang, Shupeng Wang, Guangjun Wu, Lei Zhang
2018 Lecture Notes in Computer Science  
The problem to find out the truth from inconsistent information is defined as Truth Discovery. The essence of truth discovery is to estimate source quality. Therefore the measuring mechanism of data source will immensely affect the result and process of truth discovery. However the state-of-the-art algorithms dont consider how source quality is affected when null is provided by source. We propose to use the Silent Rate, True Rate and False Rate to measure source quality in this paper. In
more » ... n, we utilize Probability Graphical Model to model truth and source quality which is measured through null and real data. Our model makes full use of all claims and null to improve the accuracy of truth discovery. Compared with prevalent approaches, the effectiveness of our approach is verified on three real datasets and the recall has improved significantly.
doi:10.1007/978-3-319-93713-7_37 fatcat:sfpax6urlrhgnjpmiflzzl2o2y

Cyclohexane oxidation: Small organic molecules as catalysts

Yicheng Zhang, Weili Dai, Guangjun Wu, Naijia Guan, Landong Li
2014 Chinese Journal of Catalysis  
., 2014 , 35: 279-285 doi: 10.1016 /S1872-2067 60024-3 Cyclohexane oxidation: Small organic molecules as catalysts Yicheng Zhang, Weili Dai, Guangjun Wu, Naijia Guan, Landong Li * Nankai University N-or  ... 
doi:10.1016/s1872-2067(14)60024-3 fatcat:vhdxelukevckjjlong624idhpu

A Novel Method of Missing Road Generation in City Blocks Based on Big Mobile Navigation Trajectory Data

Hangbin Wu, Zeran Xu, Guangjun Wu
2019 ISPRS International Journal of Geo-Information  
, Zeran Xu; resources, Guangjun Wu; writing-original draft preparation, Hangbin Wu and Zeran Xu; writing-review and editing, Hangbin Wu and Zeran Xu; visualization, Zeran Xu and Hangbin Wu; supervision  ...  Author Contributions: Conceptualization, Hangbin Wu and Guangjun Wu; methodology, Zeran Xu and Hangbin Wu; software, Zeran Xu; validation, Zeran Xu; formal analysis, Hangbin Wu and Zeran Xu; investigation  ... 
doi:10.3390/ijgi8030142 fatcat:7isxv6lfrjbvdnkcnabhvv37oy

Optimizing zeolite stabilized Pt-Zn catalysts for propane dehydrogenation

Linjun Xie, Yuchao Chai, Lanlan Sun, Weili Dai, Guangjun Wu, Naijia Guan, Landong Li
2020 Journal of Energy Chemistry  
Propane dehydrogenation (PDH) provides an alternative route to non-petroleum based propylene and eligible catalysts with good overall performance are still being explored. Herein, we report the construction of zeolite stabilized Pt-Zn catalysts Pt-Zn/Si-Beta for PDH. Characterization results from transmission electron microscopy (TEM), ultraviolet-visible (UV-vis) and Fourier transform infrared (FTIR) spectroscopy reveal that highly-dispersed Zn species are stabilized by the silanols from
more » ... e framework dealumination, which then act as the anchoring sites for Pt species. The close contact between Pt-Zn species and the electronic interaction thereof make Pt-Zn/Si-Beta robust PDH catalysts. Under optimized conditions, a high propylene production rate of 4.11 molmol À1 Pt s À1 , high propylene selectivity of 98% and a sustainable deactivation rate of ~0.02 h À1 can be simultaneously achieved at 823 K. Coke deposition is not the key reason for the catalytic deactivation, while the loss of Zn species and the resulting aggregation of Pt species under high temperatures are responsible for the irreversible deactivation of Pt-Zn/Si-Beta catalyst in PDH reaction.
doi:10.1016/j.jechem.2020.08.058 fatcat:knksyqvoi5asdhuywm4friiu2e

Nobel Metal Particles Confined in Zeolites: Synthesis, Characterization, and Applications

Yuchao Chai, Weixiang Shang, Weijie Li, Guangjun Wu, Weili Dai, Naijia Guan, Landong Li
2019 Advanced Science  
Noble metal nanoparticles or subnanometric particles confined in zeolites, that is, metal@zeolite, represent an important type of functional materials with typical core-shell structure. This type of material is known for decades and recently became a research hotspot due to their emerging applications in various fields. Remarkable achievements are made dealing with the synthesis, characterization, and applications of noble metal particles confined in zeolites. Here, the most representative
more » ... rch progress in metal@zeolites is briefly reviewed, aiming to boost further research on this topic. For the synthesis of metal@zeolites, various strategies, such as direct synthesis from inorganic or ligand-assisted noble metal precursors, multistep postsynthesis encapsulation and ion-exchange followed by reduction, are introduced and compared. For the characterization of metal@zeolites, several most useful techniques, such as electron microscopy, X-ray based spectroscopy, infrared and fluorescence emission spectroscopy, are recommended to check the successful confinement of noble metal particles in zeolite matrix and their unique physiochemical properties. For the applications of metal@zeolites, catalysis and optics are involved with an emphasis on catalytic applications including the size-dependent catalytic properties, the sintering-resistance properties, the substrate shape-selective catalysis, and catalysis modulation by zeolite microenvironment.
doi:10.1002/advs.201900299 pmid:31453060 pmcid:PMC6702632 fatcat:r5axljyguzetxjerxdf5hyebpy
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