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Single color image super-resolution using sparse representation and color constraint

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Journal of Systems Engineering and Electronics 2020年第2期31卷 266-271页

作者： XU Zhigang ma qiang YUAN Feixiang School of Computer and Communication Lanzhou University of TechnologyLanzhou 730050China

Color image super-resolution reconstruction based on the sparse representation model usually adopts the regularization norm(e.g.,L1 or L2).These methods have limited ability to keep image texture detail to some extent and are easy to cause the problem of blurring details and color artifacts in color reconstructed *** paper presents a color super-resolution reconstruction method combining the L2/3 sparse regularization model with color channel *** method converts the low-resolution color image from RGB to *** L2/3 sparse regularization model is designed to reconstruct the brightness channel of the input low-resolution color *** the color channel-constraint method is adopted to remove artifacts of the reconstructed highresolution *** method not only ensures the reconstruction quality of the color image details,but also improves the removal ability of color *** experimental results on natural images validate that our method has improved both subjective and objective evaluation.

关键词： color image sparse representation super-resolution L2/3 regularization norm color channel constraint

Mean-square Stability of Stochastic Age-dependent Delay Population Systems with Jumps

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Acta mathematicae Applicatae Sinica 2018年第1期34卷 145-154页

作者： qiang LI Qi-min ZHANG bo-qiang CAO School of mathematics and Statistics Ningxia University Yinchuan 750021 China School of mathematics and Information Sciences Beifang University of Nationalities Yinchuan 750021 China

In this paper, we present the compensated stochastic θ method for stochastic age-dependent delay population systems（SADDPSs） with Poisson jumps. The definition of mean-square stability of the numerical solution is given and a sufficient condition for mean-square stability of the numerical solution is derived. It is shown that the compensated stochastic θ method inherits stability property of the numerical solutions. Finally,the theoretical results are also confirmed by a numerical experiment.

关键词： stochastic age-dependent delay population systems compensated stochastic θ method poisson jumps mean-square stability

Indirect Electrochemical Oxidation of 4-Amino-dimethyl-aniline Hydrochloride

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Chemical Research in Chinese Universities 2006年第3期22卷 360-363页

作者： ZHANG qiang KANG bo XU Hong LIN Hai-bo Department of Chemistry College of Science Beijing Institute of Technology Beefing 100081 P. R. China College of Chemistry Jilin University Changchun 130021 P. R. China

The indirect dectrechemical oxidation of 4-amino-dimethyl-aniline hydrochloride containing wastewater generated from vanillin production is presented. Experiments were conducted at a constant current density of 30 rnA/cm^2 via a Ti/Bu-Ti-Sn ternary oxide coated anode and an undivided reactor. During the various stages of the electrolysis, parameters such as the values of chemical oxygen demand（COD） and total organic carbon（TOC） were determined in order to evaluate the feasibility of the electrochemical treatment. The energy consumption and the current efficiency during the electrolysis were calculated. The present study proves the effectiveness of the electrochemical treatment for wastewater resulted from vanillin production.

关键词： Electrochemical oxidation 4-Amino-dimethyl-aniline Wastewater treatment Vanillin

Load-carrying capacity and practical calculation method for hollow cylinder joints connected with H-shaped beams

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2012年第3期13卷 174-181页

作者： Hui WU bo-qing GAO qiang CHEN Finance and Economics of Zhejiang College Hangzhou 310018 China College of Civil Engineering and Architecture Zhejiang University Hangzhou 310058 China

A type of hollow cylinder joints connected with H-shaped beams is proposed for spatial structures. Based on von Mises yield criterion and perfect elasto-plasticity model, a series of finite element models of the joints is established, in which the effect of geometric nonlinearity is taken into account. Then mechanical behavior and load-carrying capacity of the joints were investigated, which were subjected to axial load, in- and out-plane bending moments, and their combinations. The results show that the ultimate loads of the joints are determined by the maximum displacement. Furthermore, the case of one joint connected with multiple beams was discussed. Experiments on a set of typical full-scale joints were conducted to understand the structural behavior and the failure mechanism of joint, and also to validate the finite element models. Finally, the practical calculation method was established through finite elements analysis (FEA) results and numerical fitting. The results show that the joints are more ductile and materially economical than welded hollow spherical joints, and the practical calculation method can provide a reference for direct design and the revision of relevant design codes.

关键词： Hollow cylinder joints H-shaped beams Load-carrying capacity Finite elements analysis (FEA) Practical calcu-lation method

Monotone Chains in Modulus of Two Classes of Dirichlet Coefficients

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Acta mathematica Sinica,English Series 2023年第6期39卷 1101-1114页

作者： Guang Shi Lü qiang ma School of mathematics Shandong UniversityJi'nan 250100P.R.China

Let f1,...,fkand g1,...,qkbe non-CM newforms of square-free *** byλ_(sym)jf_(i)(n)the coefficients of the Dirichlet expansion of L(sym^(j)f_(i),s)andν1,...,νkthe distinct positive integers such thatλ_(sym)jf_(i)(νi)≠*** this paper,we obtain that there exist infinitely many positive integers m such that 0<λ_(sym)jf_(1)(m+ν1)|<|λ_(sym)jf_(2)(m+ν2)|<…<|λ_(sym)jf_(k)(m+νk)|.For coefficients of the Dirichlet expansion of L(sym^(j1)f×sym^(j2)g,s),we have a similar result.

关键词： Dirichlet coefficients Sato-Tate conjecture

Storage life prediction under pre-strained thermally-accelerated aging of HTPB coating using the change of crosslinking density

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Defence Technology（防务技术） 2021年第4期17卷 1387-1394页

作者： Yong-qiang Du Jian Zheng Gui-bo Yu Shijiazhuang Campus Army Engineering UniversityShijiazhuang050003China

In order to predict the storage life of a certain type of HTPB(hydroyl-terminated polybutadiene)coating at 25℃ and analyze the influence of pre-strain on the storage life,the accelerated aging tests of HTPB coating at 40℃,50℃,60℃,70℃ with the pre-strain of 0%,3%,6%,9%,respectively were carried *** variation regularity of the change of crosslinking density was analyzed and the aging model of HTPB coating under pre-strained thermally-accelerated aging was *** storage life of HTPB coating at 25℃ was estimated by using the Berthelot equation as the end point of the aging life with a 30% decrease in maximum *** results showed that the change of crosslinking density of HTPB coating increased with the increase of aging temperature and aging time,and decreased with the increase of *** 0% prestrain,the relationship between the change of crosslinking density of HTPB coating and the aging time can be described by the logarithmic model with the confidence probability greater than 99%.The stress relaxation phenomenon existed under 3%,6%and 9%pre-strained *** aging model considering chemical aging and pre-strain was established with the confidence probability greater than 90%.The storage life of HTPB coating was 15.2935 years at 25C under 0% prestrain,which was reduced by 13.9007%,75.6949% and 89.7859% under 3%,6% and 9% pre-strain,*** existence of pre-strain has a serious impact on the storage life of HTPB coating,therefore,the pre-strain should be avoided as much as possible during the actual storage.

关键词： HTPB coating Crosslinking density Aging model Storage life prediction Berthelot

Evolution of pore structure in organic shale with typeⅢkerogen and high kaolinite content in Ningwu Basin

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Frontiers of Earth Science 2021年第4期15卷 831-848页

作者： qiang XU Hangbing LIN Yue ZHAO bo WANG Bin ma Rong DEVG Jianxin WANG Tao HOU General Prospecting Institute China National Administration of Coal GeologyBeijing 100039China Purdue University Northwest Hammond IN 46323USA Information Institute of the Ministry of Emergency management of China Beijing 100029China Shanxi Lanhua CBM Co.Ltd Jincheng 048026China PetroChina Coalbed Methane Co.Ltd Beijing 100028China Research Institute of China National Offshore Oil Corporation Beijing 100028China PetroChina Huabei Oilfield Company Renqiu 062550China

Special deposition environment makes organic-rich shales in Ningwu Basin have typeⅢkerogen and high kaolinite content,which are also famous as the kaolinite *** specific composition of shale in Ningwu Basin can change the pore structure and thus,influence the shale gas storage and *** study focuses on the pore structure and its evolution in shales with typeⅢkerogen and high kaolinite *** this study,14 Upper Paleozoic shale samples,whose total organic matter contents(TOC)range from 0.39%to 5.91%and maturities(represented by vitrinite reflectance)range from 1.22%to 2.06%,were *** electron microscopy(SEM),high-pressure mercury injection,and low-tempera-ture N2 adsorption experiments were used to analyze pore structure of these shale *** show that when the TOC content is smaller than 1.4%,the kaolinite content decreases linearly and quartz content increases linearly with increasing the TOC *** contrast,when TOC content is>1.4%,the clay content tends to increase with increasing *** on the SEM images,organic pores and clay pores were identified in shale samples with typeⅢkerogen and high kaolinite *** the maturation process,the kaolinite content decreases and illite content increases with increasing the vitrinite *** the same time,the pore volume and pore surface area both increase with increasing the vitrinite reflectance,and it may be because more organic pores and clay pores in the illite were generated during the maturation *** study can provide further understandings of shale gas accumulation in shale with typeⅢkerogen and high kaolinite content.

关键词： pore structure type IE kerogen kaolinite low-temperature N_(2 adsorption high-pressure mercury porosimetry influencing)factors

An experimental study on dynamic response for MICP strengthening liquefiable sands

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Earthquake Engineering and Engineering Vibration 2016年第4期15卷 673-679页

作者： Han Zhiguang Cheng Xiaohui ma qiang Department of Civil Engineering Tsinghua University Beijing 100084 China Institute of Airforce Engineering Design Beijing 100070 China

The technology of bio-gronting is a new technique for soft ground improvement. many researchers have carried out a large number of experiments and study on this topic. However, few studies have been carried out on the dynamic response of solidified sand samples, such reducing liquefaction in sand. To study this characteristic of microbial-strengthened liquefiable sandy foundation, a microorganism formula and grouting scheme is applied. After grouting, the solidified samples are tested via dynamic triaxial testing to examine the cyclic performance of solidified sand samples. The results indicate that the solidified sand samples with various strengths can be obtained to meet different engineering requirements, the use of bacteria solution and nutritive salt is reduced, and solidified time is shortened to 1-2 days. Most importantly, in the study of the dynamic response, it is found that the MICP grouting scheme is effective in improving liquefiable sand characteristic, such as liquefaction resistance.

关键词： bacteria bio-grouting microorganism induced CaCO3 precipitation (MICP) grouting scheme design dynamic response

Conductive Au nanowires regulated by silk fibroin nanofibers

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Frontiers of materials Science 2014年第1期8卷 102-105页

作者： bo-Ju DONG qiang LU National Engineering Laboratory for Modern Silk College of Textile and Clothing Engineering Soochow University Suzhou 215123 China

Conductive Au-biopolymer composites have promising applications in tissue engineering such as nerve tissue regeneration. In this study, silk fibroin nanofibers were formed in aqueous solution by regulating silk self-assembly process and then used as template for Au nanowire fabrication. We performed the synthesis of Au seeds by repeating the seeding cycles for several times in order to increase the density of Au seeds on the nanofibers. After electroless plating, densely decorated Au seeds grew into irregularly shaped particles following silk nanofiber to fill the gaps between particles and finally form uniform continuous nanowires. The conductive property of the Au-silk fibroin nanowires was studied with current-voltage （I-V） measurement. A typical ohmic behavior was observed, which highlighted their potential applications in nerve tissue regeneration.

关键词： silk Au nanowire electrical conductivity biological device