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Semi-supervised local feature selection for data classification

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Science China(Information Sciences) 2021年第9期64卷 127-138页

作者： Zechao LI Jinhui tang School of Computer Science and Engineering Nanjing University of Science and Technology

Conventional feature selection methods select the same feature subset for all classes, which means that the selected features might work better for some classes than the others. Towards this end, this paper proposes a new semi-supervised local feature selection method(S2 LFS) allowing to select different feature subsets for different classes. According to this method, class-specific feature subsets are selected by learning the importance of features considering each class separately. In particular, the class labels of all available data are jointly learned under a consistent constraint over the labeled data, which enables the proposed method to select the most discriminative features. Experiments on six data sets demonstrate the effectiveness of the proposed method compared to some popular feature selection methods.

关键词： local feature selection label-specific feature semi-supervised learning data classification discriminative feature

Biological significance of RNA-seq and single-cell genomic research in woody plants

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Journal of Forestry Research 2019年第5期30卷 1555-1568页

作者： Wei tang Anna Y.tang College of Arts and Science East Carolina UniversityGreenvilleNC 27858USA University of North Carolina at Chapel Hill 101 Stadium DriveChapel HillNC 27514USA

RNA-seq and single-cell genomic research emerge as an important research area in the recent years due to its ability to examine genetic information of any number of single cells in all living *** knowledge gained from RNA-seq and single-cell genomic research will have a great impact in many aspects of plant *** this review,we summary and discuss the biological significance of RNA-seq and single-cell genomic research in plants including the single-cell DNA-sequencing,RNA-seq and single-cell RNA sequencing in woody plants,methods of RNA-seq and single-cell RNA-sequencing,single-cell RNA-sequencing for studying plant development,and single-cell RNA-sequencing for elucidating cell type *** will focus on RNA-seq and single-cell RNA sequencing in woody plants,understanding of plant development through single-cell RNAsequencing,and elucidation of cell type composition via single-cell *** presented in this review will be helpful to increase our understanding of plant genomic research in a way with the power of plant single-cell RNA-sequencing analysis.

关键词： Cell type composition Genomics Plant development Single-cell RNA-sequencing methods

An economic way to achieve all-weather CO2 reduction

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National Science Review 2024年第3期11卷 46-47页

作者： Junwang tang Department of Chemical Engineering University College London

Utilising solar power to convert carbon dioxide（CO2） into hydrocarbon fuels presents an eco-friendly method to address dependence on fossil fuels and contribute to a net-zero CO2emission goal[1,2].

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Experimental investigation and analytically modeling of hysteretic behavior of rigid bus-flexible connectors of 220 kV electrical substations

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Earthquake Engineering and Engineering Vibration 2023年第3期22卷 841-852页

作者： tang Tingxuan He Jun Department of Civil Engineering School of Naval ArchitectureOcean and Civil EngineeringShanghai Jiao Tong UniversityShanghai 200240China

This paper describes the quasi-static testing and analytical modelling of the hysteretic behavior of aluminum alloy rigid bus-flexible connectors of 220 kV electrical *** main objective of the study is to experimentally investigate the hysteretic behavior of six different types of rigid bus-flexible connectors 220 kV electrical substations when subjected to cyclic *** objective is to theoretically study the flexibility and effectiveness of a previously proposed analytical model in fitting the experimental hysteresis loops of the tested rigid bus-flexible *** experimental investigation indicates that the tested rigid bus-flexible connectors exhibit highly asymmetric hysteresis behavior along with tension stiffening *** theoretical study demonstrates that the generalized Bouc-Wen model has high flexibility and is effective in fitting the experimental hysteresis resisting force-displacement curves of the six tested rigid bus-flexible connectors.

关键词： rigid bus-flexible connectors 220 kV electrical substations hysteretic behavior experimental curves analytical model

VR helicity density and its application in turbomachinery tip leakage flows

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Chinese Journal of Aeronautics 2022年第11期35卷 1-17页

作者： Yumeng tang Yangwei LIU School of Energyand Power Engineering Beihang UniversityBeijing 100083China National Key Laboratory of Science and Technology on Aero-Engine Aero-Thermodynamics Beihang UniversityBejing 100083China State Key Laboratory of Aerodynamics China Aerodynamics Research and Development CenterMianyang 621000China

Helicity is an important quantity that represents the topological interpretation of vortices;however,helicity is not a Galilean *** this study,VR helicity density(HVR)is derived via taking the dot product of vorticity with the unit real eigen vector of the velocity gradient tensor when the complex eigenvalues *** analytical solution of HVR is derived to resolve it in a local pointwise manner,and the Galilean invariance of HVR is *** leakage flow structures in a direct numerical simulation of a tip leakage flow model and a delayed detached eddy simulation of a low-speed large-scale axial compressor rotor are extracted using helicity,eigen helicity density and HVR *** show that the utilization of HVR permits the identification and accentuation of concentrated *** identified by HVR appear in more connective *** in the case of helicity,the sign of HVR distinguishes between primary and secondary vortices,while eigen helicity density *** normalized HVR is superior to the normalized helicity density in locating the vortex axis,especially for the induced vortex ***,HVR is a strong candidate to replace the helicity density,especially when Galilean invariance is required.

关键词： Compressor Flow visualization Helicity Tip leakage flow Vortex identification Vortical flow

News event prediction by trigger evolution graph and event segment

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Journal of Systems Engineering and Electronics 2023年第3期34卷 615-626页

作者： ZHANG Yaru tang Xijin Academy of Mathematics and Systems Science Chinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

Event prediction aims to predict the most possible following event given a chain of closely related context *** methods based on event pairs or the entire event chain may ignore much structural and semantic *** datasets for event prediction,naturally,can be used for supervised *** chains are either from document-level procedural action flow,or from news sequences under the same *** paper leverages graph structure knowledge of event triggers and event segment information for event prediction with general news corpus,and adopts the standard multiple choice narrative cloze task *** topic model is utilized to extract event chains from the news corpus to deal with training data *** on trigger-guided structural relations in the event chains,we construct trigger evolution graph,and trigger representations are learned through graph convolutional neural network and the novel neighbor selection *** there are features of two levels for each event,namely,text level semantic feature and trigger level structural *** design the attention mechanism to learn the features of event segments derived in term of event major subjects,and integrate relevance between event segments and the candidate *** most possible next event is picked by the *** results on the real-world news corpus verify the effectiveness of the proposed model.

关键词： event prediction trigger evolution graph event segment

Evaluation Model and Method of Margin in Electromagnetic Environmental Effects for Complex Systems

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Chinese Journal of Electronics 2021年第1期30卷 171-179页

作者： tang Shiping MAO Junfa Key Laboratory of Ministry of Education of Design and Electromagnetic Compatibility of High Speed Electronic System Shanghai Jiao Tong University Research Center for Electromagnetic Environmental Effects Southeast University

Margin is an important index in the control of Electromagnetic environmental effects(E3) and Electromagnetic compatibility(EMC) design for *** to define and verify the E3 margins of complex systems such as ships and airplanes is a difficult problem.A new method of system-level E3 margin evaluation is proposed. Based on the theory of fault tree, the evaluation model of system-level margin is *** complex system function is transformed into the equipment and subsystem that affect the function, and the relationship between margin of system-level and equipment is established. The change from margin of equipment to system-level margin is realized. According to the action process of Electromagnetic environment(EME), the verification and evaluation methods of EME domain, response domain and effect domain are put forward. The margin calculation formula of EME domain and typical electromagnetic energy coupling response are deduced. The problem of margin evaluation for equipment under different input parameters is solved. A typical application example is given. The verification test scheme is designed. The methods of electromagnetic energy radiation and injection are adopted. The system-level margin is analyzed by the data obtained from the effective test verification. The results show that the model and method are reasonable and feasible.

关键词： effect domain evaluation methods fault trees typical electromagnetic energy coupling response E3 margin evaluation response domain margin calculation formula ships EME domain complex systems Electromagnetic environmental effects electromagnetic compatibility system-level margin evaluation model complex system function

Transgenic woody plants for biofuel

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Journal of Forestry Research 2014年第2期25卷 225-236页

作者： Wei tang Anna Y.tang Department of Biology East Carolina University 101 Stadium Drive University of North Carolina at Chapel Hill

Transgenic trees as a new source for biofuel have brought a great interest in tree biotechnology. Genetically modifying forest trees for ethanol production have advantages in technical challenges, costs, environmental concerns, and financial problems over some of crops. Genetic engineering of forest trees can be used to reduce the level of lignin, to produce the fast-growing trees, to develop trees with higher cellulose, and to allow the trees to be grown more widely. Trees can establish themselves in the field with less care of farmers, compared to most of crops. Transgenic crops as a new source for biofuel have been recently reviewed in several reviews. Here, we overview transgenic woody plants as a new source for biofuel including genetically modified woody plants and environment; main focus of woody plants genetic modifications; solar to chemical energy transfer; cellulose biosynthesis; lignin biosynthesis; and cellulosic ethanol as biofuel.

关键词： biofuel cell wall cellulose lignin transgenic tree

Dark Touristic Perception: Motivation, Experience and Benefits Interpreted from the Visit to Seismic Memorial Sites in Sichuan Province

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Journal of Mountain Science 2014年第5期11卷 1326-1341页

作者： tang Yong Department of Tourism Development and Management College of Tourism and Urban-rural Planning Chengdu University of Technology

This study investigates the motivations of Chinese domestic tourists visiting seismic memorial sites after the great Wenchuan earthquake of 2008, and examines their interpretation of experiences and benefits of the visits. Recent research on dark tourism has raised the possibility that people are attracted to death and memorial sites in ways different from other tourist attractions. The study used an empirical research design employing questionnaires to collect data from 255 Chinese domestic visitors at seismic memorial sites in west Sichuan. Analysis revealed that the obligation of commemoration mixed with curiosity represents a different set of travel motivation in dark tourism settings than in other kinds of tourism. In addition, the empirical evidence also suggests an interrelated pattern between motivations, experiences and benefits. This study implies that Chinese domestic tourists were attracted in ways different from other tourist attractions both because they tended to fulfill their obligation of commemoration and were interested in destruction; and visitor experiences played an important mediating role between travel motivations and benefits gained.

关键词： Dark Tourism Travel Motivation Tourist Perception Chinese Domestic Tourists Seismic Memorial sites Wenchuan earthquake Mountains