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Petroleum Science 2022年第2期19卷 486-497页

作者： Long-Hui bai Bo Liu Yi-Jing Du Bo-Yang Wang Shan-Si Tian Liu Wang zhi-Qiang xue Accumulation and Development of Unconventional Oil and Gas State Key Laboratory Cultivation BaseNortheast Petroleum UniversityDaqingHeilongjiang 163318China Hubei Key Laboratory of Petroleum Geochemistry and Environment Yangtze UniversityWuhanHubei 430100China Research Institute of Petroleum Exploration&Development Beijing100083China No.1 Institute of Geological and Mineral Resources Survey of Henan LuoyangHenan 471000China

The pore structure and oil content of shales have an important influence on the oil mobility and *** this study,the lacustrine shale samples from the Qingshankou Formation(Q1)of Songliao Basin were ***,pyrolysis,XRD and nitrogen adsorption were performed on the original and extracted shale *** the influence of mineral composition and organic matter(OM)on the development of nano-scale pore,the oil phase states and mobility were *** Q1 shale samples can be sub-divided into three types according to the isotherm *** A samples are characterized by high kerogen content,with oil mainly existing in the free phase *** B samples are characterized by medium kerogen content,oil mainly exists in the absorbed phase *** C samples are characterized by low kerogen content,with trace oil found in the absorbed phase ***-scale organic pores are well developed in the Q1 *** is primarily found in the pore spaces with diameters less than 10 nm,this being the pore size threshold for mobile shale *** TOC>2.0 wt%and EOM>1.0 wt%,Q1 Formation shale oil mobility is high,resulting in prospective drilling targets.

关键词： Shale oil mobility Oil phase state Extraction Nitrogen adsorption

Lightweight Al-Nb-Ti-V-Cr high entropy alloys with high hardness and enhanced mechanical properties via doping Co

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China Foundry 2025年

作者： Fang-dong Xu De-zhi Chen Rui-run Chen Bin Gan Jing-yue Yu National Key Laboratory for Precision Hot Processing of Metals Harbin Institute of Technology Suzhou Laboratory

To develop high-hardness and high-strength lightweight high entropy alloys （LHEAs）,a series of CoxAlNbTiVCr alloys were *** phase constitution,distribution,and crystal structure of the Laves phase in alloys can be altered by adjusting the composition of HEAs,which in turn influences their mechanical *** Nb Ti VCr （x=0,0.5,1,1.5,and 2,atomic ratio percentage） LHEAs were designed and prepared to characterize the microstructure and tailor the mechanical *** introduction of Co changes the microstructure of LHEAs from a single B2 structure to a mixture dendrite structure,which consists of B2 phase,C14 and C15 Laves *** the C14 and C15 Laves phases exhibit coupled *** parameters including mixing enthalpy (ΔHmix),valence electron concentration （VEC）,atomic radius size （δ）,mixing entropy （ΔS）,and electronegativity difference （Δχ） are used to predict the formation of B2 and Laves phase in *** the Co content increases from 0 to 1.5at.%,Laves phase volume fraction gradually increases,which leads to an enhancement in the compressive strength from 1,520.8 MPa to 1,844.4 ***1.5Al Nb Ti VCr alloy exhibits the maximum Vickers hardness of 699.4 *** improvement of mechanical properties mainly originates from solid solution strengthening and second phase strengthening.

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Synthetic security assessment based on variable consistency dominance-based rough set approach

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High Technology Letters 2010年第4期16卷 413-421页

作者：赵亮 xue zhi Department of Electronic Engineering Shanghai Jiao Tong University Shanghai 200240 P.R. China

Security assessment can help understand the security conditions of an information system and yield results highly conducive to the solution of security problems in it. Taking the computer networks in a certain university as samples, this paper, with the information system security assessment model as its foundation, proposes a multi-attribute group decision-making （MAGDM） security assessment method based on a variable consistency dominance-based rough set approach （VC-DRSA）. This assessment method combines VC-DRSA with the analytic hierarchy process （AHP）, uncovers the inherent information hidden in data via the quality of sorting （QoS）, and makes a synthetic security assessment of the information system after determining the security attribute weight. The sample findings show that this method can effectively remove the bottleneck of MAGDM, thus assuming practical significance in information system security assessment.

关键词： multi-attribute group decision-making (MAGDM) security assessment variable consistency dominance-based rough set approach (VC-DRSA)

Gaussian particle filter based pose and motion estimation

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第10期8卷 1604-1613页

作者： WU xue-dong SONG zhi-huan State Key Lab. of Industrial Control Technology Institute of Industrial Process Control Zhejiang University Hangzhou 310027 China Department of Electronic Information and Electrical Engineering Fujian University of Technology Fuzhou 350014 China

Determination of relative three-dimensional （3D） position, orientation, and relative motion between two reference frames is an important problem in robotic guidance, manipulation, and assembly as well as in other fields such as photogrammetry. A solution to pose and motion estimation problem that uses two-dimensional （2D） intensity images from a single camera is desirable for real-time applications. The difficulty in performing this measurement is that the process of projecting 3D object features to 2D images is a nonlinear transformation. In this paper, the 3D transformation is modeled as a nonlinear stochastic system with the state estimation providing six degrees-of-freedom motion and position values, using line features in image plane as measuring inputs and dual quaternion to represent both rotation and translation in a unified notation. A filtering method called the Gaussian particle filter （GPF） based on the panicle filtering concept is presented for 3D pose and motion estimation of a moving target from monocular image sequences. The method has been implemented with simulated data, and simulation results are provided along with comparisons to the extended Kalman filter （EKF） and the unscented Kalman filter （UKF） to show the relative advantages of the GPF. Simulation results showed that GPF is a superior alternative to EKF and UKF.

关键词： Gaussian particle filter (GPF) Pose and motion estimation Line features Monocular vision Extended Kalman filter(EKF) Unscented Kalman filter (UKF) Dual quatemion

Synthetic security assessment for incomplete interval-valued information system

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High Technology Letters 2012年第2期18卷 160-166页

作者：赵亮 xue zhi School of Electronic and Electric Engineering Shanghai Jiaotong University.Shanghai 200240China

In order to understand the security conditions of the incomplete interval-valued information system （IllS） and acquire the corresponding solution of security problems, this paper proposes a multi-attribute group decision- making （MAGDM） security assessment method based on the technique for order performance by similarity to ideal solution （TOPSIS）. For IllS with preference information, combining with dominance-based rough set approach （DRSA）, the effect of incomplete interval-valued information on decision results is discussed. For the imprecise judgment matrices, the security attribute weight can be obtained using Gibbs sampling. A numerical example shows that the proposed method can acquire some valuable knowledge hidden in the incomplete interval-valued information. The effectiveness of the proposed method in the synthetic security assessment for IIIS is verified.

关键词： security assessment incomplete interval-valued information system(IIIS) multi-attribute group decision-making(MAGDM) technique for order performance by similarity to ideal solution(TOPSIS) dominance- based rough set approach(DRSA) Gibbs sampling

Theoretical Study on the Catalytic Activity and Sulfur Resistibility of Amorphous Alloy Ni-B-P

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Chinese Journal of Structural Chemistry 2007年第3期26卷 273-280页

作者： FANG zhi-Gang GUO Jing-xue School of Chemical Engineering University of Science and Technology Liaoning Anshan 114051 China

In the present paper, one hundred cluster models NinBP （n = 1-6） have been designed and studied by density functional theory （DFT） to get an insight into the local structure, catalytic properties and sulfur resistibility of amorphous alloy Ni-B-P. The configurations in triplet state are found more stable than those in the singlet state. It is found： that as the content of Ni in the clusters increases, the value of Fermi level in clusters fluctuated, which shows that the content of Ni can influence the Fermi level to a certain extent. Based on the Fermi level and DOS, we consider the activity of catalyst in hydrogenation reaction is the best in cluster Ni3BP. On the basis of the charge of clusters NinBP （n = 1 -6）, we conclude the amorphous alloy Ni-B-P with high Ni content has better sulfur resistibility and the best hydrogenation activity, strong sulfur resistibility appears in clusters Ni3BP, and the amorphous alloy Ni60B20P20 with similar proportion is expected to prepare in the future.

关键词： amorphous alloy Ni-B-P DFT catalytic activity sulfur resistibility

Stem cell therapy: A promising treatment for COVID-19

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World Journal of Clinical Cases 2021年第36期9卷 11148-11155页

作者： zhi-xue Zheng Department of General Surgery Beijing Jishuitan HospitalBeijing 100035China

Novel coronavirus disease 2019(COVID-19)caused by severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)has become a global ***-2 is an RNA virus and has a glycosylated spike(S)protein used for genome ***-19 can lead to a cytokine storm and patients usually have early respiratory signs and further secondary infections,which can be ***-19 has entered an emergency phase,but there are still no specific effective drugs for this *** stem cells(MSCs)are multipotent stromal cells,which cause antiapoptosis and can repair damaged epithelial *** clinical trials have proved that MSC therapy could be a potential feasible therapy for COVID-19 patients,especially those with acute respiratory distress syndrome,without serious adverse events or ***,more studies are needed in the future,in order to confirm the effect of this therapy.

关键词： COVID-19 SARS-CoV-2 Mesenchymal stem cells Pandemic Stem cell therapy

Rounded Data Analysis Based on Multi-Layer Ranked Set Sampling

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Acta Mathematica Sinica,English Series 2011年第12期27卷 2507-2518页

作者： Wei Ming LI zhi Dong bai KLMIB and School of Mathematics and Systems Science Beijing University of Aeronautics and Astronautics Beijing 100191 P. R. China Key Laboratory for Applied Statistics of MOE and School of Mathematics and Statistics Northeast Normal University Changchun 130024 P. R. China

Observations of sampling are often subject to rounding, but are modeled as though they were unrounded. This paper examines the impact of rounding errors on parameter estimation with multi-layer ranked set sampling. It shows that the rounding errors seriously distort the behavior of covariance matrix estimate, and lead to inconsistent estimation. Taking this into account, we present a new approach to implement the estimation for this model, and further establish the strong consistency and asymptotic normality of the proposed estimators. Simulation experiments show that our estimates based on rounded multi-layer ranked set sampling are always more efficient than those based on rounded simple random sampling.

关键词： Rounding error multi-layer ranked set sampling work likelihood method

Induced pluripotent stem cell-related approaches to generate dopaminergic neurons for Parkinson's disease

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Neural Regeneration Research 2025年第11期20卷 3193-3206页

作者： Ling-Xiao Yi Hui Ren Woon Genevieve Saw Li Zeng Eng King Tan zhi Dong Zhou National Neuroscience Institute Singapore Nanyang Technology University Singapore Department of Neurology Singapore General HospitalSingapore Signature Research Program in Neuroscience and Behavioral Disorders Duke-NUS Medical SchoolSingapore

The progressive loss of dopaminergic neurons in affected patient brains is one of the pathological features of Parkinson's disease,the second most common human neurodegenerative *** the detailed pathogenesis accounting for dopaminergic neuron degeneration in Parkinson's disease is still unclear,the advancement of stem cell approaches has shown promise for Parkinson's disease research and *** induced pluripotent stem cells have been commonly used to generate dopaminergic neurons,which has provided valuable insights to improve our understanding of Parkinson's disease pathogenesis and contributed to anti-Parkinson's disease *** current review discusses the practical approaches and potential applications of induced pluripotent stem cell techniques for generating and differentiating dopaminergic neurons from induced pluripotent stem *** benefits of induced pluripotent stem cell-based research are *** dopaminergic neuron differentiation protocols from induced pluripotent stem cells are *** emerging three-dimension-based brain organoid models compared with conventional two-dimensional cell culture are ***,limitations,challenges,and future directions of induced pluripotent stem cell–based approaches are analyzed and proposed,which will be significant to the future application of induced pluripotent stem cell-related techniques for Parkinson's disease.

关键词： dopaminergic neurons induced pluripotent stem cells Parkinson's disease stem cell approaches

Soil Fertility Self-development Under Ecological Restoration in the Zhuxi Watershed in the Red Soil Hilly Region of China

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Journal of Mountain Science 2014年第5期11卷 1231-1241页

作者： bai Li-yue CHEN zhi-qiang CHEN zhi-biao College of Geographical Sciences Fujian Normal University Institute of Agriculture Regional Planning of Fujian Province

Current methods that utilize simple data or models to judge whether soil fertility can selfdevelop are not sufficiently rigorous. A new framework has been set up using catastrophe theory, laboratory experiment, field work, and 3S(Geographic information system, Global positioning system, and Remote sensing) to explore soil fertility catastrophe under ecological restoration, discriminate whether soil fertility can self-develop, and propose adjustment of ecological restoration measures in the Zhuxi watershed of Changting County, Fujian Province, China, which is a typical representative of the red soil hilly region of China. The results show that: 1) the soil fertility is obviously improved through the four ecological restoration measures, which impels soil fertility catastrophe. Among 89 soil samples, catastrophic soil samples and stable soil samples account for 26(29.21%) and 63(70.79%) of the samples, respectively. The four ecological restoration measures are listed in the order lowquality forest improvement > arbor–bush–herb mixed plantation > orchard improvement > closing measures according to the proportions of catastrophic soil samples. A typical soil sample in Bashilihe that can self-develop is selected as the criterion to judge the upper lobe and lower lobe of soil fertility in the process surface of the Cusp catastrophe model. Twenty-six(29.21%) were in the middle lobe, 10(11.24%) were in the upper lobe, and 53(70.79%) were in the lower lobe. The catastrophic direction of 26 catastrophic soil samples is to the upper lobe according to soil and water loss change as well as fieldwork. There is a significant positive correlation of Δ with soil and water loss change, and the lower soil and water loss relates to higher catastrophic probability. 2) Soil fertility self-development could be regionalized as "Soil fertility can self-develop" whose area was 12.74 km2(28.33%) distributed mainly in the leftmost and rightmost parts, "Soil fertility tends to self-develop" who

关键词： Soil fertility Catastrophe Ecological restoration Red soil hilly region