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Experimental analysis of pore structure and fractal characteristics of soft and hard coals with same coalifcation

International Journal of Coal Science & Technology 2022年第4期9卷 107-121页

作者： Barkat Ullah Yuanping Cheng Liang Wang Weihua Yang Izhar Mithal Jiskani biao hu School of Safety Engineering China University of Mining and TechnologyXuzhouChina School of Resources and Safety Engineering Central South UniversityChangshaChina NUST Balochistan Campus National University of Sciences and TechnologyQuettaPakistan

Accurate and quantitative investigation of the physical structure and fractal geometry of coal has important theoretical and practical signifcance for coal bed methane(CBM)development and the prevention of dynamic disasters such as coal and gas *** study investigates the pore structure and fractal characteristics of soft and hard coals using nitrogen and carbon dioxide(N_(2)/CO_(2))*** samples from Pingdingshan Mine in Henan province of China were collected and pulverized to the required size(0.20–0.25 mm).N_(2)/CO_(2)adsorption tests were performed to evaluate the specifc surface area(SSA),pore size distribution(PSD),and pore volume(PV)using Braunuer-Emmett-Teller(BET),Barrett-Joyner-Halenda(BJH),and Density Functional Theory(DFT).The pore structure was characterized based on the theory of fractal *** results unveiled that the strength of coal has a signifcant infuence on pore structure and fractal *** are signifcant diferences in SSA and PV between both *** BJH-PV and BET-SSA obtained by N_(2)-adsorption for soft coal are 0.029–0.032 cm^(3)/g and 3.523–4.783 m^(2)/*** the values of PV and SSA obtained by CO_(2)-adsorption are 0.037–0.039 cm^(3)/g and 106.016–111.870 m^(2)/*** coal shows greater SSA and PV than hard coal,which is consistent with the adsorption capacity(VL).The fractal dimensions of soft and hard coal are respectively *** Ding coal exhibits larger D1 and smaller D_(2),and the reverse for the Wu coal seam is *** greater the value of D1(complexity of pore surface)of soft coal is,the larger the pore surface roughness and gas adsorption capacity *** results enable us to conclude that the characterization of pores and fractal dimensions of soft and hard coals is diferent,tending to diferent adsorption/desorption *** this regard,the results provide a reference for formulating corresponding coal and gas outburst prevention and control measures.

关键词： Methane adsorption Soft and hard coal Pore structure Fractal characteristics N_(2)/CO_(2)adsorption

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BnWRI1 coordinates fatty acid biosynthesis and photosynthesis pathways during oil accumulation in rapeseed

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Journal of Integrative Plant Biology 2014年第6期56卷 582-593页

作者： Xue-Long Wu zhi-Hong Liu Zhang-hua hu Rui-zhi huang Institute of Virology and Biotechnology Zhejiang Academy of Agricultural Sciences Key Laboratory of Plant Metabolic Engineering of Zhejiang Province

Photosynthesis in“green”seeds, such as rapeseed, soybean, and Arabidopsis, plays a substantial role in the improved efficiency of oil accumulation. However, the molecular mecha-nism underpinning the coordinated expression of fatty acid （FA） biosynthesis-and photosynthesis-related genes in such develop-ing seeds remains to be elucidated. Here, we found that seed-specific overexpression of BnWRI1, a WRI1 homolog from rapeseed （Brassica napus cv. ZGY2）, results in enhanced chlorophyl content in developing seeds and increased oil content and seed mass in matured seeds. BnWRI1 was co-expressed with BnBCCP and BnCAB, two marker genes of FA biosynthesis and photosynthesis during seed development, respectively. Over-expression of BnWRI1 increased expression of both marker genes. Further, the nuclear-localized BnWRI1 protein was found to act as a transcription activator. It could bind to the GT1-element and/or GCC-box, which are widespread in the upstream regions of genes involved in FA biosynthesis and photosynthesis pathways. Accordingly, BnWRI1 could interact with promoters of BCCP2 and LHB1B2 in vivo. These results suggested that BnWRI1 may coordinate FA biosynthesis and photosynthesis pathways in developing seeds via directly stimulating expression of GT1-element and/or GCC-box containing genes.

关键词： BnWRI1 Brassica napus oil accumulation photosynthesis transcription factor

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社交媒体健康信息用户信任形成机理研究

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现代情报 2025年第1期45卷 97-111页

作者：初彦伯王萍胡姝姝吉林大学商学与管理学院吉林长春130012

[目的/意义]在公共卫生事件频发的背景下,国民对健康信息需求急剧增长。社交媒体作为用户信息获取的重要途径之一,在高效传播健康信息的同时,也为虚假健康信息的产生和传播提供便利条件。随着社交媒体渗透力和影响力不断扩大,用户对健... 详细信息

[目的/意义]在公共卫生事件频发的背景下,国民对健康信息需求急剧增长。社交媒体作为用户信息获取的重要途径之一,在高效传播健康信息的同时,也为虚假健康信息的产生和传播提供便利条件。随着社交媒体渗透力和影响力不断扩大,用户对健康信息的不确定感愈发强烈。鉴于此,本文对社交媒体健康信息用户的信任形成机理进行探索,以期为后续相关研究提供参考和借鉴。[方法/过程]解构社交媒体健康信息用户信任形成的要素,建构面向用户感知过程的信任综合框架,从用户、信息和环境3个方面提出社交媒体健康信息用户信任理论假设模型,并对结构模型进行修正。[结果/结论]研究从理论层面明晰社交媒体健康信息用户感知信任过程以及用户心理变化的进程。研究还发现热评情感极性、涉入度、信源可信度、冲突解决对信任存在显著的正向影响。信任对采纳意愿存在显著的正向影响。参照群体规范对采纳意愿存在显著的正向影响。此外,信任分别在热评情感极性、涉入度、信源可信度和冲突解决与信息采纳意愿之间起到完全中介作用。

关键词：社交媒体健康信息信任感知可信度

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Interaction between the atmospheric boundary layer and a standalone wind turbine in Gansu—Part II： Numerical analysis

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Science China(Physics,Mechanics & Astronomy) 2018年第9期61卷 59-68页

作者： zhi Zheng zhiTeng Gao DeShun Li RenNian Li Ye Li QiuHao hu WenRui hu School of Energy and Power Engineering Lanzhou University of Technology Lanzhou 730050 China Gansu Provincial Technology Centre for Wind Turbines Lanzhou 730050 China Key Laboratory of Fluid Machinery and Systems Lanzhou 730050 China School of Naval Architecture Ocean and Civil Engineering Shanghai Jiao Tong University Shanghai 200240 China Institute of Mechanics Chinese Academy of Sciences Beijing 100080 China

To analyze the interaction between wind turbines and the atmospheric boundary layer, we integrated a large-eddy simulation with an actuator line model and examined the characteristics of wind-turbine loads and wakes with reference to a corresponding experiment in Gansu. In the simulation, we set the wind turbine to have a rotor diameter of 14.8 m and a tower height of 15.4 m in the center of an atmospheric boundary layer with a 10.6° yaw angle. The results reveal an obviously skewed wake structure behind the rotor due to the thrust component normal to the flow direction. The power spectra of the inflow fluctuation velocity exhibit a region of-5/3 slope, which confirms the ability of large-eddy simulations to reproduce the energy cascade from larger to smaller scales. We found there to be more energy in the power spectrum of the axial velocity, which shows that coherent turbulence structures have more energy in the horizontal direction. By the conjoint analysis of atmospheric turbulence and windturbine loads, we found that when the inflow wind direction changes rapidly, the turbulence kinetic energy and coherent turbulence kinetic energy in the atmospheric turbulence increase, which in turn causes fluctuations in the wind turbine ***, anisotropic atmospheric turbulence causes an asymmetric load cycle, which imposes a strike by the turbine blade on the shaft, thereby increasing the fatigue load on the shaft. Our main conclusion is that the atmospheric boundary layer has a strong effect on the evolution of the wake and the structural response of the turbine.

关键词： wind power atmospheric turbulence effects finite volume methods large-eddy simulations

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Change of lake area in the southeastern part of China's Badain Jaran Sand Sea and its implications for recharge sources

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Journal of Arid Land 2015年第1期7卷 1-9页

作者： zhi ZHANG zhiBao DONG ChangZhen YAN GuangYin hu Key Laboratory of Desert and Desertification Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences

Understanding the relationship between the changes in lake water volume and climate change can provide valuable information to the recharge sources of lake water. This is particularly true in arid areas such as the Badain Jaran Sand Sea, an ecologically sensitive area, where the recharge sources of lakes are heatedly debated. In this study, we determined the areas of 50 lakes （representing 70% of the total permanent lakes in this sand sea） in 1967, 1975, 1990, 2000 and 2010 by analyzing remote-sensing images using image processing and ArGIS software. In general, the total lake area decreased from 1967 to 1990, remained almost unchanged from 1990 to 2000, and increased from 2000 to 2010. Analysis of the relationship between these changes and the contemporaneous changes in annual mean temperature and annual precipitation in the surrounding areas suggests that temperature has significantly affected the lake area, but that the influence of precipitation was minor. These results tend to su- pport the palaeo-water recharge hypothesis for lakes of the Badain Jaran Sand Sea, considering the fact that the distribution and area of lakes are closely related to precipitation and the size of mega-dunes, but the contemporaneous precipitation can hardly balance the lake water.

关键词： arid environment lake change source of water recharge climate change

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Pairing-Free ID-Based Key-Insulated Signature Scheme

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Journal of Electronic Science and Technology 2015年第1期13卷 33-38页

作者： Guo-Bin Zhu hu Xiong zhi-Guang Qin School of Computer Science and Engineering University of Electronic Science and Technology of China

Without the assumption that the private keys are kept secure perfectly, cryptographic primitives cannot be deployed in the insecure environments where the key leakage is inevitable. In order to reduce the damage caused by the key exposure in the identity-based（ID-based） signature scenarios efficiently, we propose an ID-based key-insulated signature scheme in this paper, which eliminates the expensive bilinear pairing operations. Compared with the previous work, our scheme minimizes the computation cost without any extra cost. Under the discrete logarithm（DL） assumption, a security proof of our scheme in the random oracle model has also been given.

关键词： Identity-based cryptography key-insulated random oracle mode signature

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Testing Serial Correlation in Semiparametric Varying-Coefficient Partially Linear EV Models

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Acta Mathematicae Applicatae Sinica 2008年第1期24卷 99-116页

作者： Xue-mei hu zhi-zhong Wang Feng Liu School of Mathematics and Computing Technology Central South University Changsha 410075 China School of Mathematics and Physics Chongqing Institute of Technology Chongqing 400050 China

This paper studies estimation and serial correlation test of a semiparametric varying-coefficient partially linear EV model of the form Y = X^Tβ ＋Z^Tα（T）＋ε,ξ = X ＋ η with the identifying condition E[（ε,η^T）^T] =0, Cov[（ε,η^T）^T] = σ^2Ip＋1. The estimators of interested regression parameters /3 , and the model error variance σ2, as well as the nonparametric components α（T）, are constructed. Under some regular conditions, we show that the estimators of the unknown vector β and the unknown parameter σ2 are strongly consistent and asymptotically normal and that the estimator of α（T） achieves the optimal strong convergence rate of the usual nonparametric regression. Based on these estimators and asymptotic properties, we propose the VN,p test statistic and empirical log-likelihood ratio statistic for testing serial correlation in the model. The proposed statistics are shown to have asymptotic normal or chi-square distributions under the null hypothesis of no serial correlation. Some simulation studies are conducted to illustrate the finite sample performance of the proposed tests.

关键词： Varying-coefficient model partial linear EV model the generalized least squares estimation serial correlation empirical likelihood

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新型浆锚连接方钢管混凝土拼接柱抗震性能试验研究

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土木与环境工程学报（中英文） 2025年第1期47卷 152-166页

作者：郑立文李智赵亮胡少伟李景浩齐浩重庆大学土木工程学院重庆400045 郑州大学水利与交通工程学院郑州450001 中国电子科技集团公司第二十九研究所成都610036

为进一步提高用于钢-混凝土组合结构的柱构件的装配效率,并改善其抗震性能,降低生产成本,提出一种新型浆锚连接方钢管混凝土拼接柱设计方法。通过对缩尺比例为2的5个拼接柱构件和1个整浇柱构件开展拟静力试验,获得不同配筋率、配筋形式... 详细信息

为进一步提高用于钢-混凝土组合结构的柱构件的装配效率,并改善其抗震性能,降低生产成本,提出一种新型浆锚连接方钢管混凝土拼接柱设计方法。通过对缩尺比例为2的5个拼接柱构件和1个整浇柱构件开展拟静力试验,获得不同配筋率、配筋形式和柱-柱节点拼接部位的新型拼接柱的抗震性能。试验结果表明:新型拼接柱构件在低周期反复荷载下的破坏过程及其形态与整浇柱构件相似,其滞回曲线饱满,耗能能力、抗承载力退化和抵抗变形(刚度)能力均比整浇柱构件更加优良,特别是将柱-柱节点拼接部位设于柱间反弯点区域的P类型构件变形能力最佳,证明了该新型拼接柱设计方法的科学性,并对提高钢-混凝土组合框架结构的整体抗震性能具有应用潜力。

关键词：钢管混凝土柱浆锚连接拼接部位拟静力试验抗震性能

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Knowledge modeling based on interval-valued fuzzy rough set and similarity inference: prediction of welding distortion

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Journal of Zhejiang University-Science C(Computers and Electronics) 2014年第8期15卷 636-650页

作者： zhi-qiang FENG Cun-gen LIU hu huANG Maritime College Qinzhou University State Key Laboratory of Ocean Engineering Shanghai Jiao Tong University

Knowledge-based modeling is a trend in complex system modeling technology. To extract the process knowledge from an information system, an approach of knowledge modeling based on interval-valued fuzzy rough set is presented in this paper, in which attribute reduction is a key to obtain the simplified knowledge model. Through defining dependency and inclusion functions, algorithms for attribute reduction and rule extraction are obtained. The approximation inference plays an important role in the development of the fuzzy system. To improve the inference mechanism, we provide a method of similaritybased inference in an interval-valued fuzzy environment. Combining the conventional compositional rule of inference with similarity based approximate reasoning, an inference result is deduced via rule translation, similarity matching, relation modification, and projection operation. This approach is applied to the problem of predicting welding distortion in marine structures, and the experimental results validate the effectiveness of the proposed methods of knowledge modeling and similarity-based inference.

关键词： Knowledge modeling Interval-valued fuzzy rough set Similarity-based inference Welding distortion prediction

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Strong Mixing Subshift of Finite Type and Hausdorff Measure of Its Chaotic Set

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Acta Mathematica Sinica,English Series 2011年第4期27卷 789-798页

作者： Wan Gan SONG zhi hu hua Ming WU School of Mathematical Science Peking University Beijing 100871 P. R. China School of Computer Science and Technology Huaibei Coal Industry Teachers Huaibei 235000 P. R. China School of Mathematical and Computer Science Zhanjiang Teachers College Zhanjiang 524048 P. R. China

We present a sufficient and necessary condition for the subshift of finite type to be a measure-preserving transformation or to be a strong mixing measure-preserving transformation with respect to the Hausdorff measur... 详细信息

关键词： Symbolic space a finite subshift chaotic set Hausdorff measure

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