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Rare Metals 2013年第4期32卷 390-396页

作者： Chang-Hao Wang ze-Hua Wang ze-Hua Zhou Shao-Qun Jiang Xiao-Feng Xue jing-jing Yao College of Mechanics and Materials Hohai University School of Materials Science and Engineering Shanghai University

Al2O3-metal composite coatings with different reactants and diluents were fabricated on mild steel plate with nonpressure combustion synthesis process. The coat-ings were characterized by means of X-ray diffraction, scanning electron microscopy, and energy-dispersive spec-trometry, respectively. Thermal shock tests were carried out to determine the bond strength of the coating with the steel substrate. The results indicate that the coating is composed of α-A1203, α-（Fe-Cr） and Al2SiO5 as the main phases. It is found that the coating with the diluents of Al2O3-SiO2 and transition layer of Al2O3-Cr presents the *** hardness of 2270 HV0.2 and the lowest porosity of 3.93 %. Owing to a metallurgical bond of the coating-to-substrate, the coating exhibits a good thermal shock resistance.

关键词： Combustion synthesis Al2O3-metalcomposite coating Diluents Thermal shock resistance

Cubic Diophantine Inequalities

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Acta Mathematica Sinica,English Series 2001年第1期17卷 153-160页

作者： Hong ze li Department of Mathematics Shandong University

Let λ1, λ2,...,λ7 be real numbers satisfying λi≥1. In this paper, we prove there are integers x1,...,x7 such that the inequalities |λ1x13+λ2x23+...+λ7x73|i|xi]3 （λ1λ2…λ7）89814) hold simultaneously.

关键词： Diophantine inequality Cubic equation Non-trivial solution

A Theoretical Model for Characterizing the Internal Contact of the CICC Strands under Axial Strain

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Acta Mechanica Solida Sinica 2016年第5期29卷 455-467页

作者： Shuai Dong ze jing Huadong Yong Youhe Zhou Key Laboratory of Mechanics on Disaster and Environment in Western China The Ministry of Education of Chinaand Department of Mechanics and Engineering SciencesCollege of Civil Engineering and MechanicsLanzhou University School of Mechano-Electronic Engineering Xidian University

A theoretical model is proposed to calculate the internal contact distributions and contact forces of a 3×4×4×4 twisted NbSn cable under applied axial *** critical current density reduction of the whole cable can be *** thin rod theory is employed to analyze the mechanical behavior of each *** to the regular helical structure,the contact distribution of each strand is obtained,and the contact force in the cable is *** last,a prediction about the critical current density of the twisted cable is *** results show that decreasing the pitch length can reduce the contact forces between strands.

关键词： modulus cable strand length resultant decreasing pitch helical twisted radius

Redshift drift constraints on holographic dark energy

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Science China(Physics,Mechanics & Astronomy) 2017年第3期60卷 80-86页

作者： Dong-ze He jing-Fei Zhang Xin Zhang Department of Physics College of Sciences Northeastern University Center for High Energy Physics Peking University

The Sandage-Loeb （SL） test is a promising method for probing dark energy because it measures the redshift drift in the spectra of Lyman-o： forest of distant quasars, covering the ＂redshift desert＂ of 2 ≤ z ≤ 5, which is not covered by existing cosmological observations. Therefore, it could provide an important supplement to current cosmological observations. In this paper, we explore the impact of SL test on the precision of cosmological constraints for two typical holographic dark energy models, i.e., the original holographic dark energy （HDE） model and the Ricci holographic dark energy （RDE） model. To avoid data inconsistency, we use the best-fit models based on current combined observational data as the fiducial models to simulate 30 mock SL test data. The results show that SL test can effectively break the existing strong degeneracy between the present-day matter density Ωm0 and the Hubble constant 1-1o in other cosmological observations. For the considered two typical dark energy models, not only can a 30-year observation of SL test improve the constraint precision of Ωm0 and h dramatically, but can also enhance the constraint precision of the model parameters c and α significantly.

关键词： redshift drift Sandage-Loeb test holographic dark energy Ricci dark energy cosmological constraints

First observation results of Macao Science Satellite-1 on lightning-induced electron precipitation

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Science China Earth Sciences 2025年第1期 1-10页

作者： Yongping WANG Yixin SUN Qiugang ZONG Gaopeng LU Xudong GU ze-Jun HU Bin li Key Laboratory for Polar Science Ministry of Natural Resources Polar Research Institute of China Institute of Space Physics and Applied Technology Peking University State Key Laboratory of Lunar and Planetary Science Macau University of Science and Technology School of Earth and Space Sciences University of Science and Technology of China School of Electronic Information Wuhan University

The Medium-energy Electron Spectrometers(MES) is a space-borne instrument onboard Macao Science Satellite-1(MSS-1) dedicated to monitoring the typical charged particle radiation characteristics in the satellite orbit and the process of their occurrence and development, including short bursts of lightning-induced electron precipitation(LEP).This paper presents the first results of the LEP measurements by the MSS-1.47 LEP events are identified with the routine operation for 3 months since satellite launch, all within the range of 1.5lightning discharges are definitively geo-located for these LEP *** LEP events occur within lightning and consist of 40–300 keV electrons.A preliminary observation result indicates that, with medium-energy electron detectors, MSS-1can present in-situ observations of large regions of enhanced background precipitation and reveal their fine spatiotemporal characteristics and spectral *** collaborative VLF ground-based measurements at the Great Wall Station, Antarctica also have a good correspondence with LEP measurements of *** observations also imply that lightning activity has a modulation effect on the energetic electron energy-spatial structure.

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Joint DOA and channel estimation with data detection based on 2D unitary ESPRIT in massive MIMO systems

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Frontiers of Information Technology & Electronic Engineering 2017年第6期18卷 841-849页

作者： jing-ming KUANG Yuan ZHOU ze-song FEI School of Information and Electronics Beijing Institute of TechnologyBeijing 100081China

We propose a novel method for joint two-dimensional (2D) direction-of-arrival (DOA) and channel estimation with data detection for uniform rectangular arrays (URAs) for the massive multiple-input multiple-output (MIMO) systems. The conventional DOA estimation algorithms usually assume that the channel impulse responses are known exactly. However, the large number of antennas in a massive MIMO system can lead to a challenge in estimating accurate corresponding channel impulse responses. In contrast, a joint DOA and channel estimation scheme is proposed, which first estimates the channel impulse responses for the links between the transmitters and antenna elements using training sequences. After that, the DOAs of the waves are estimated based on a unitary ESPRIT algorithm using previous channel impulse response estimates instead of accurate channel impulse responses and then, the enhanced channel impulse response estimates can be obtained. The proposed estimator enjoys closedform expressions, and thus it bypasses the search and pairing processes. In addition, a low-complexity approach toward data detection is presented by reducing the dimension of the inversion matrix in massive MIMO *** cases for the proposed method are analyzed by changing the number of antennas. Experimental results demonstrate the validity of the proposed method.

关键词： Two-dimensional (2D) direction-of-arrival (DOA) estimation Channel impulse response estimation Data detection Uniform rectangular array (URA) Massive multiple-input multiple-output (MIMO)

Nest survival rate of Reeves＇s pheasant(Syrmaticus reevesii) based on artificial nest experiments

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Zoological Research 2017年第1期38卷 49-54页

作者： Xu Luo Yu-ze Zhao jing Ma Jian-Qiang li Ji-liang Xu School of Nature Conservation Beijing Forestry University Beijing 100083 China

To explore the nest survival rate of Reeves＇ s pheasant（Syrmaticus reevesii） and the nest-site factors that affect it, we conducted artificial nest experiments with reference to natural nests at Dongzhai National Nature Reserve（DNNR）, Henan Province and Pingjingguan, Hubei Province from April to June 2014 simulating the situation in its early and later breeding season. We also determined distance characteristics of the nest sites by Arc GIS 10.0. Nest survival models were constructed in Program MARK for data analysis. Results indicated that in the early breeding season, the apparent survival rate（ASR） in DNNR（52.4%） was significantly greater than that in Pingjingguan（13.5%）, and the ASR in the later breeding season in DNNR（26.7%） was not indistinctively correlated with Pingjingguan（3.2%）. The daily survival rate（DSR） in the later breeding season was 93.8% in DNNR and 92.0% in Pingjingguan, respectively. The DSRs were both negatively correlated with nest distance to forest edges and settlements. The DSR in Pingjingguan was positively correlated with nest distance to paths and negatively correlated with nest distance to water sources. However, the DSR in DNNR was negatively correlated with nest distance to paths but positively correlated with nest distance to water sources.

关键词： Reeves's pheasant SyrmaUcus reevesfi Nest survival rate Artificial nest experiments.

Moment Redistribution Effect of the Continuous Glass Fiber Reinforced Polymer-Concrete Composite Slabs Based on Static Loading Experiment

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Structural Durability & Health Monitoring 2025年第1期19卷 105-123页

作者： Zhao-Jun Zhang Wen-Wei Wang jing-Shui Zhen Bo-Cheng li De-Cheng Cai Yang-Yang Du Hui Huang Offshore Oil Engineering Co.Ltd. Tianjin300461China Department of Bridge Engineering School of TransportationSoutheast UniversityNanjing211189China

This study aimed to investigate the moment redistribution in continuous glass fiber reinforced polymer(GFRP)-concrete composite slabs caused by concrete cracking and steel bar yielding in the negative bending moment *** experimental bending moment redistribution test was conducted on continuous GFRP-concrete composite slabs,and a calculation method based on the conjugate beam method was *** composite slabs were formed by combining GFRP profiles with a concrete layer and supported on steel beams to create two-span continuous composite slab *** methods,epoxy resin bonding,and stud connection,were used to connect the composite slabs with the steel *** experimental findings showed that the specimen connected with epoxy resin exhibited two moments redistribution phenomena during the loading process:concrete cracking and steel bar yielding at the internal *** contrast,the composite slab connected with steel beams by studs exhibited only one-moment redistribution phenomenon throughout the loading *** the concrete at the internal support cracked,the bending moment decreased in the internal support section and increased in the midspan *** the steel bars yielded,the bending moment further decreased in the internal support section and increased in the mid-span *** GFRP profiles do not experience cracking,there was no significant decrease in the bending moment of the mid-span *** test specimens experienced compressive failure of concrete at the mid-span *** results showed good agreement between the calculated and experimental values of bending moments in the mid-span section and internal support *** proposed model can effectively predict the moment redistribution behavior of continuous GFRP-concrete composite slabs.

关键词： Moment redistribution GFRP-concrete composite slabs bending moment experimental study analysis model

Data streams classification with ensemble model based on decision-feedback

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The Journal of China Universities of Posts and Telecommunications 2014年第1期21卷 79-85页

作者： liU jing XU Guo-sheng ZHENG Shi-hui XIAO Da GU li-ze Information Security Center Beijing University of Posts and Telecommunications National Engineering Laboratory for Disaster Backup and Recovery Beijing University of Posts and Telecommunications

The main challenges of data streams classification include infinite length, concept-drifting, arrival of novel classes and lack of labeled instances. Most existing techniques address only some of them and ignore others. So an ensemble classification model based on decision-feedback（ECM-BDF） is presented in this paper to address all these challenges. Firstly, a data stream is divided into sequential chunks and a classification model is trained from each labeled data chunk. To address the infinite length and concept-drifting problem, a fixed number of such models constitute an ensemble model E and subsequent labeled chunks are used to update E. To deal with the appearance of novel classes and limited labeled instances problem, the model incorporates a novel class detection mechanism to detect the arrival of a novel class without training E with labeled instances of that class. Meanwhile, unsupervised models are trained from unlabeled instances to provide useful constraints for E. An extended ensemble model Ex can be acquired with the constraints as feedback information, and then unlabeled instances can be classified more accurately by satisfying the maximum consensus of Ex. Experimental results demonstrate that the proposed ECM-BDF outperforms traditional techniques in classifying data streams with limited labeled data.

关键词： ensemble classification novel class concept drifting decision-feedback

Adsorption and Diffusion of Hydrogen Atom on Low-index Ag Planes

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Chinese Journal of Structural Chemistry 2005年第10期24卷 1217-1223页

作者： ZHANG jing DIAO Zhao-Yu WANG ze-Xin Department of Chemistry Shandong Normal University Jinan 250014 China

The 5-parameter Morse potential （5-MP） of the interaction between H atom and Ag surfaces has been constructed. The adsorption and diffusion of H on Ag low-index surfaces are investigated with 5-MP in detail. The characteristics of critical points are obtained. The theoretical results show that H atom can only adsorb at the three-fold site on Ag（111 ）; the quasi-3-fold site and long-bridge site are stable adsorption sites on Ag（110） surface for the H atom, and at low coverage hydrogen predominantly occupies the quasi-3-fold site. This work predicts that the four-fold hollow site is the most stable adsorption state for H atom on Ag（100）. The results of this work are approved by the experimental and theoretical results.

关键词： H-Ag system 5-MP adsorption vibration low-index surfaces