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Journal of Natural Gas Chemistry 2012年第1期21卷 1-6页

作者： rongjun Zhang Dehua He Innovative Catalysis Program Key Lab of Organic Optoelectronics and Molecular EngineeringDepartment of ChemistryTsinghua UniversityBeijing 100084China

A series of ZrO2 catalysts were prepared by treating ZrO（OH）2 hydrogel with different alcohol solvents （C2-C4 alcohols） and calcining under N2 flow at 773 K for 3 h. The obtained ZrO2 catalysts were systematically characterized by the methods of N2 adsorption-desorption, powder X-ray diffraction, NH3 temperature-programmed desorption, and CO2 temperature-programmed desorption. The catalytic performance of each catalyst was evaluated in the selective synthesis of iso-C4 （isobutene and isobutane） and light olefins （C2-C4） from CO hydrogenation. The specific surface area increased for the ZrO2 catalysts obtained by treating ZrO（OH）2 hydrogel with different alcohol solvents. The amounts of both acidic and basic sites on the catalyst surface increased obviously. The catalytic activity （CO conversion） of ZrO2 catalysts also increased after the treatment with different alcohol solvents. The nighest activity was obtained over the catalyst which was pretreated with isopropanol. However, alcohol solvent treatment retarded the transformation of ZrO2 crystal structure from tetragonal phase to monoclinic phase, and subsequently resulted in the decrease of monoclinic phase in ZrO2, which led to the decrease of olefin selectivity in corresponding hydrocarbon products （C2-C4/CH）.

关键词： wmonoclinic ZrO2 isosynthesis isobutene acid-base light olefins

The role of machine intelligence in photogrammetric 3D modeling-an overview and perspectives

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International Journal of Digital Earth 2021年第1期14卷 15-31页

作者： rongjun Qin Armin Gruen Department of Civil Environmental and Geodetic EngineeringThe Ohio State UniversityColumbusOHUSA Department of Electrical and Computer Engineering The Ohio State UniversityColumbusOHUSA Translational Data Analytics Institute The Ohio State UniversityColumbusOHUSA Information Architecture ETH ZürichZürichSwitzerland

The process of modern photogrammetry converts images and/or LiDAR data into usable 2D/3D/4D *** photogrammetric industry offers engineering-grade hardware and software components for various *** some components of the data processing pipeline work already automatically,there is still substantial manual involvement required in order to obtain reliable and high-quality *** recent development of machine learning techniques has attracted a great attention in its potential to address complex tasks that traditionally require manual *** is therefore worth revisiting the role and existing efforts of machine learning techniques in the field of photogrammetry,as well as its neighboring field computer *** paper provides an overview of the state-of-the-art efforts in machine learning in bringing the automated and‘intelligent’component to photogrammetry,computer vision and(to a lesser degree)to remote *** will primarily cover the relevant efforts following a typical 3D photogrammetric processing pipeline:(1)data acquisition(2)georeferencing/interest point matching(3)Digital Surface Model generation(4)semantic interpretations,followed by conclusions and our insights.

关键词： Photogrammetry camera calibration 3D modeling machine learning object recognition semantic interpretation

Optimal Design of Surface Structure of a Magnetic Head

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Chinese Journal of Mechanical Engineering 2009年第5期22卷 651-657页

作者： WANG Yazhen NIU rongjun HUANG Ping School of Mechanical andAutomotive Engineering South China University of Technology Guangzhou 510640 China Guangdong College of Industry and Commerce Guangzhou 510510 China

Currently, the surface structure of a magnetic head has been transferred from a positive to a negative model. In order to increase magnetic storage density and to decrease the flight height, the surface structure of a head needs to be optimized continually. In the present paper, the influence of surface structure of a negative magnetic head on its flight attitude is analyzed in brief by both theoretical analysis and numerical simulation. Firstly, based on theoretical analysis, one-dimensional model of optimal design is built whose results play an important role in guiding for the two-dimensional model. Secondly, to analyze the impacts of different slructures of negative pressure heads, the original head structure is divided into five zones; the impacts of different zones on both pressure distribution and load carrying capacity were detailed analyzed by numerical analysis. Thirdly, remain the leading-head structure of the negative head, and optimized tail-end structure can be gained by the regional planning strategy to control the gas film pressure distribution. With layout strategy, three kinds of structures of the head were designed. The results show that the tail-end structure impacts on the flight performances significantly and the middle boss plays a major role on positive pressure, while the bilateral bosses lying in either side play assistant regulating role. The structures of bilateral bosses have slightly impact on pressure distribution. The results also show that an optimum tail structure can meet the needs of a lower flight height and a larger magnetic storage density.

关键词： surface structure optimum design numerical analysis

On deep holes of standard Reed-Solomon codes

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Science China Mathematics 2012年第12期55卷 2447-2455页

作者： WU rongjun HONG ShaoFang Mathematical College Sichuan University Chengdu 610064 China Yangtze Center of Mathematics Sichuan University Chengdu 610064 China

Determining deep holes is an important open problem in decoding Reed-Solomon codes. It is well known that the received word is trivially a deep hole if the degree of its Lagrange interpolation polynomial equals the dimension of the Reed-Solomon code. For the standard Reed-Solomon codes [p-1, k]p with p a prime, Cheng and Murray conjectured in 2007 that there is no other deep holes except the trivial ones. In this paper, we show that this conjecture is not true. In fact, we find a new class of deep holes for standard Reed-Solomon codes [q-1, k]q with q a power of the prime p. Let q≥4 and 2≤k≤q-2. We show that the received word u is a deep hole if its Lagrange interpolation polynomial is the sum of monomial of degree q-2 and a polynomial of degree at most k-1. So there are at least 2(q-1)qk deep holes if k q-3.

关键词： deep hole Reed-Solomon code cyclic code BCH code DFT IDFT

PGAM5-Mediated PHB2 Dephosphorylation Contributes to Diabetic Cardiomyopathy by Disrupting Mitochondrial Quality Surveillance

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Research 2023年第3期2022卷 171-185页

作者： rongjun Zou Jun Tao Jie He Chaojie Wang Songtao tan Yu Xia Xing Chang Ruibing Li Ge Wang Hao Zhou Xiaoping Fan Department of Cardiovascular Surgery Guangdong Provincial Hospital of Chinese MedicineThe Second Afiliated Hospital of Guangzhou University of Chinese MedicineGuangzhou 510120GuangdongChina The Second Clinical College of Guangzhou University of Chinese Medicine Guangzhou 510405GuangdongChina Department of Cardiovascular Surgery Sun Yat-sen Memorial HospitalSun Yat-sen UniversityGuangzhou 510120GuangdongChina Senior Department of Cardiology The Sixth Medical Center of People's Liberation Army General HospitalBeijing 100048China Guang'anmen Hospital China Academy of Chinese Medical SciencesBeijing 100053China.

Disruption of the mitochondrial quality surveillance(MQS)system contributes to mitochondrial dysfunction in diabetic cardiomyopathy(DCM).In this study,we observed that cardiac expression of phosphoglycerate mutase 5(PGAM5),a mitochondrial Ser/Thr protein phosphatase,is upregulated in mice with streptozotocin-induced ***,DCM-related cardiac structural and functional deficits were negated in cardiomyocyte-specific Pgam5 knockout(Pgam5^(CKO))*** stress impaired adenosine triphosphate production,reduced respiratory activity,and prolonged mitochondrial permeability transition pore opening in acutely isolated neonatal cardiomyocytes from control Pgam5^(f/f) mice,and these effects were markedly prevented in cardiomyocytes from Pgam5^(CKO) ***,three main MQS-governed processes—namely,mitochondrial fission/fusion cycling,mitophagy,and biogenesis—were disrupted by hyperglycemia in Pgam5^(f/f),but not in Pgam5^(CKO),*** the basis of bioinformatics prediction of interaction between PGAM5 and prohibitin 2(PHB2),an inner mitochondrial membrane-associated scaffolding protein,co-immunoprecipitation,and immunoblot assays demonstrated that PGAM5 dephosphorylates PHB2 on *** of cardiomyocytes with phosphodefective or phosphomimetic Ser91 mutants of PHB2 confirmed a critical role for PGAM5-mediated dephosphorylation of PHB2 in mitochondrial dysfunction associated with hyperglycemic ***,knockin mice expressing phosphomimetic PHB2^(S91D) were resistant to diabetes-induced cardiac *** findings highlight the PGAM-PHB2 axis as a novel and critical regulator of mitochondrial dysfunction in DCM.

关键词： PHB2 cycling impaired

Light People: Academician Junhao Chu

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Light(Science & Applications) 2023年第6期12卷 955-964页

作者： Hui Wang rongjun Zhang Cun Yu Changchun Institute of Optics Fine Mechanics and PhysicsChinese Academy of Sciences3888 Dong Nan Hu Road130033 ChangchunChina Fudan University 220 Handan RoadYangpu District200433 ShanghaiChina

Editorial The industrial revolutions of steam power,electric power and digital power have been three key steps in the development of science and ***,the fourth industrial revolution has quietly begun,a revolution which will combine the powers of modern technologies such as the Internet,industrial digitalization and virtual reality to trigger a major change of science and technology,and sensor technology is of vital importance to this process.

关键词： Academician revolution steps

Neural network based adaptive nonsingular practical predefined-time fault-tolerant control for hypersonic morphing aircraft

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Chinese Journal of Aeronautics 2024年第4期37卷 421-435页

作者： Shihao XU Changzhu WEI Litao ZHANG rongjun MU School of Astronautics Harbin Institute of TechnologyHarbin 150001China Beijing Institute of Control&Electronics Technology Beijing 100038China

This paper develops a novel Neural Network(NN)-based adaptive nonsingular practical predefined-time controller for the hypersonic morphing aircraft subject to actuator faults. Firstly, a novel Lyapunov criterion of practical predefined-time stability is established. Following the proposed criterion, a tangent function based nonsingular predefined-time sliding manifold and the control strategy are developed. Secondly, the radial basis function NN with a low-complexity adaptation mechanism is incorporated into the controller to tackle the actuator faults and uncertainties. Thirdly, rigorous theoretical proof reveals that the attitude tracking errors can converge to a small region around the origin within a predefined time, while all signals in the closed-loop system remain bounded. Finally, numerical simulation results are presented to verify the effectiveness and improved performance of the proposed control scheme.

关键词： Hypersonic morphing aircraft(HMA) Neural network(NN) Adaptive control Practical predefined-time control Fault-tolerant control

A strength model for cement-stabilized mud subjected to various curing temperatures and its early-stage quality control

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第11期16卷 4727-4741页

作者： Sijie Liu rongjun Zhang Junjie Zheng Lin Chen School of Civil Engineering Wuhan UniversityWuhan430072China Rock Mechanics in Hydraulic Structural Engineering Ministry of EducationWuhan430072China School of Civil and Hydraulic Engineering Huazhong University of Science and TechnologyWuhan430074China

The influence of curing temperature on the strength development of cement-stabilized mud has been well documented in terms of strength-increase rate and ultimate ***,the strength development model is not mature for the extremely early *** addition,there is a lack of studies on quality control methods based on early-stage strength *** paper presents a strength model for cement-stabilized mud to address these gaps,considering various curing temperatures and early-stage *** this study,a series of laboratory experiments was conducted on two types of muds treated with Portland blast furnace cement and ordinary Portland cement under four different *** results indicate that elevated temperatures expedite strength development and lead to higher long-term *** proposed model,which combines a three-step conversion process and a hyperbolic model at the reference temperature,enables accurate estimate of the strength development for cement-treated mud with any proportions cured under various *** this model,a practical early quality control method is introduced for applying cement-stabilized mud in field *** back-analysis parameters obtained from a 36-h investigation at temperature of 60C demonstrated a sufficient accuracy in predicting strength levels in practical applications.

关键词： Cement-stabilized mud Curing temperature Early stage Quality control Strength development

Unravel the Charge-Carrier Dynamics in Simple Dimethyl Oxalate-Treated Perovskite Solar Cells with Efficiency Exceeding 22%

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Energy & Environmental Materials 2023年第5期6卷 219-227页

作者： rongjun Zhao Tai Wu Rongshan Zhuang Yong Hua Yude Wang Yunnan Key Laboratory for Micro/Nano Materials&Technology School of Materials and EnergyYunnan UniversityKunming 650504China Key Lab of Quantum Information of Yunnan Province Yunnan UniversityKunming 650504China

Understanding the effect of additive on the interfacial charge-carrier transfer dynamics is very crucial to obtaining highly efficient perovskite solar cells(PSCs).Herein,we designed a simple additive,dimethyl oxalate(DO),functioning as an effective defect passivator of perovskite grain boundaries via the coordination interaction between the carbonyl(C=O)and the exposed Pb^(2+).The modification with DO produces pinhole-free and compact perovskite films,enhancing the transportation capability of *** a consequence,the DO-treated PSCs exhibited a power conversion efficiency(PCE)of 22.19%,which is significantly higher than that of the control device without additive(19.58%).More importantly,detailed transient absorption characterization reveals that the use of additive can decrease the hot-carrier cooling dynamics,improve the carrier transfer,and eliminate nonradiative recombination in *** present work provides a profound understanding the additives effect on the carrier dynamics in PSCs toward the Shockley-Queisser limit.

关键词： additive engineering carrier dynamics defect passivation Perovskite solar cell

Bifurcation control of solid angle car-following model through a time-delay feedback method

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2023年第9期24卷 828-840页

作者： Qun JI Hao LYU Hang YANG Qi WEI rongjun CHENG Faculty of Maritime and Transportation Ningbo UniversityNingbo 315211China Ningbo University of Finance&Economics Ningbo 315175China

In order to alleviate unstable factor-caused bifurcation and reduce oscillations in traffic flow,a feedback control with consideration of time delay is designed for the solid angle model(SAM).The stability and bifurcation condition of the new SAM is derived through linear analysis and bifurcation analysis,and then accurate range of stable region is *** order to explore the mechanism of the influence of multiple parameter combinations on the stability of controlled systems,a definite integral stabilization method is provided to determine the stable interval of time delay and feedback *** simulations are explored to verify the feasibility and effectiveness of the proposed model,which also demonstrate that feedback gain and delay are two key factors to alleviate traffic congestion in the SAM.

关键词： Solid angle model(SAM) Time-delay Hopf bifurcation Feedback control Parameter calibration