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New Splitting Algorithms for Multiplicative Noise Removal Based on Aubert-Aujol Model

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Numerical Mathematics(Theory,Methods and Applications) 2022年第2期15卷 415-441页

作者： Yu Gan Jie Zhang huibin chang School of Mathematical Sciences Tianjin Normal UniversityTianjinChina Department of Mathematics The University of Hong KongHong KongSARChina

In this paper,we propose new algorithms for multiplicative noise removal based on the Aubert-Aujol(AA)model.By introducing a constraint from the forward model with an auxiliary variable for the noise,the NEMA(short for Noise Estimate based Multiplicative noise removal by alternating direction method of multipliers(ADMM))is firstly given.To further reduce the computational cost,an additional proximal term is considered for the subproblem with regard to the original variable,the NEMA_(f)(short for a variant of NEMA with fully splitting form)is further proposed.We conduct numerous experiments to show the convergence and performance of the proposed algorithms.Namely,the restoration results by the proposed algorithms are better in terms of SNRs for image deblurring than other compared methods including two popular algorithms for AA model and three algorithms of its convex variants.

关键词： Alternating direction method of multipliers image denoising and deblurring multiplicative noise total variation

Augmented Lagrangian Methods for p-Harmonic Flows with the Generalized Penalization Terms and Application to Image Processing

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Numerical Mathematics(Theory,Methods and Applications) 2013年第1期6卷 1-20页

作者： huibin chang Xue-Cheng Tai School of Mathematical Sciences Tianjin Normal UniversityTianjin 300387 Department of Mathematics East China Normal UniversityShanghai 200241China Department of Mathematics University of BergenJohaness Brunsgate 12Bergen 5007Norway

In this paper,we propose a generalized penalization technique and a convex constraint minimization approach for the p-harmonic flow problem following the ideas in[Kang&March,IEEE T.Image Process.,16(2007),2251–2261].We use fast algorithms to solve the subproblems,such as the dual projection methods,primal-dual methods and augmented Lagrangian methods.With a special penalization term,some special algorithms are presented.Numerical experiments are given to demonstrate the performance of the proposed methods.We successfully show that our algorithms are effective and efficient due to two reasons:the solver for subproblem is fast in essence and there is no need to solve the subproblem accurately(even 2 inner iterations of the subproblem are enough).It is also observed that better PSNR values are produced using the new algorithms.

关键词： p-harmonic flows denoising generalized penalization terms saddle-point problem image processing augmented Lagrangian methods

A Boosting Procedure for Variational-Based Image Restoration

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Numerical Mathematics(Theory,Methods and Applications) 2018年第1期11卷 49-73页

作者： Samad Wali Zhifang Liu Chunlin Wu huibin chang School of Mathematical Sciences Nankai UniversityTianjinChina School of Mathematical Sciences Tianjin Normal UniversityTianjinChina

Variational methods are an important class of methods for general image restoration.Boosting technique has been shown capable of improving many image denoising algorithms.This paper discusses a boosting technique for general variation-al image restoration methods.It broadens the applications of boosting techniques to a wide range of image restoration problems,including not only denoising but also deblur-ring and inpainting.In particular,we combine the recent SOS technique with dynamic parameter to variational methods.The dynamic regularization parameter is motivated by Meyer’s analysis on the ROF model.In each iteration of the boosting scheme,the variational model is solved by augmented Lagrangian method.The convergence analy-sis of the boosting process is shown in a special case of total variation image denoising with a“disk”input data.We have implemented our boosting technique for several im-age restoration problems such as denoising,inpainting and deblurring.The numerical results demonstrate promising improvement over standard variational restoration mod-els such as total variation based models and higher order variational model as total generalized variation.

关键词： Variational method image restoration total variation boosting augmented Lagrangian method

新型乙烯基吡唑丙烯腈类化合物的合成及杀螨活性

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农药 2024年第5期63卷 325-329页

作者：张斌杨辉斌常秀辉宋玉泉李斌汪国庆沈阳科创化学品有限公司沈阳110144 沈阳中化农药化工研发有限公司新农药创制与开发国家重点实验室农药国家工程研究中心沈阳110021

[目的]为了发现结构新颖的杀螨活性化合物。[方法]以腈吡螨酯为先导化合物,在丙烯腈结构中引入乙烯基吡唑结构片断,设计合成了15个新型乙烯基吡唑丙烯腈类化合物,并对其进行杀螨活性测试。[结果]初步的室内生物活性测试结果表明:目标化... 详细信息

[目的]为了发现结构新颖的杀螨活性化合物。[方法]以腈吡螨酯为先导化合物,在丙烯腈结构中引入乙烯基吡唑结构片断,设计合成了15个新型乙烯基吡唑丙烯腈类化合物,并对其进行杀螨活性测试。[结果]初步的室内生物活性测试结果表明:目标化合物6a~6h均表现出较好的杀螨活性,在100 mg/L质量浓度下对朱砂叶螨致死率均≥99%。其中化合物6 g表现最佳,在10 mg/L下对朱砂叶螨致死率仍为88%。[结论]当羟基上的H被烷基羰基、烷氧基羰基取代时,化合物具有较好的杀螨活性。

关键词：乙烯基吡唑丙烯腈合成杀螨活性

7个匍匐翦股颖抗褐斑病的初步比较及生理响应

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河北农业大学学报 2024年第1期47卷 58-65,90页

作者：张雅晰孙建苗王逍冬董康挺刘畅王丽宏李会彬孙鑫博河北农业大学农学院/河北省作物生长调控重点实验室河北保定071000 河北农业大学植物保护学院/华北作物改良与调控国家重点实验室河北保定071000

为筛选抗病匍匐翦股颖材料,本实验对立枯丝核菌接菌侵染后的7个匍匐翦股颖材料的生理指标进行测定,通过主成分分析对其抗病性进行综合比较。结果表明,受到病原菌入侵后,植物叶片的叶绿素、可溶性蛋白(SP)、过氧化氢(H_(2)O_(2))含量下降... 详细信息

为筛选抗病匍匐翦股颖材料,本实验对立枯丝核菌接菌侵染后的7个匍匐翦股颖材料的生理指标进行测定,通过主成分分析对其抗病性进行综合比较。结果表明,受到病原菌入侵后,植物叶片的叶绿素、可溶性蛋白(SP)、过氧化氢(H_(2)O_(2))含量下降;丙二醛(MDA)、可溶性糖(SS)、游离脯氨酸(Pro)、超氧化物歧化酶(SOD)、过氧化氢酶(CAT)、过氧化物酶(POD)、谷胱甘肽还原酶(APX)含量上升。将这10个生理指标转化为4个主成分因子,计算出得分D值,评分最高的为‘光芒’。通过主成分分析法综合各项生理指标表明:7个品种匍匐翦股颖的抗病性排序为光芒>A-1>007>A4>朝阳>宣言>佳美,为后续匍匐翦股颖抗病机制的研究以及抗病新品种的培育奠定基础。

关键词：匍匐翦股颖褐斑病生理响应抗病性评价

A Scheme for a Sustainable Urban Water Environmental System During the Urbanization Process in China

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Engineering 2018年第2期4卷 26-29页

作者： huibin Yu Yonghui Song Xin chang Hongjie Gao Jianfeng Peng Department of Urban Water Environmental Research Chinese Research Academy of Environmental Sciences Beijing 100012 China School of Environment Beijing Normal University Beijing 100875 China

Urbanization is a potential factor in economic development, which is a main route to social development. As the scale of urbanization expands, the quality of the urban water environment may deteriorate, which can have a negative impact on sustainable urbanization. Therefore, a comprehensive understanding of the functions of the urban water environment is necessary, including its security, resources, ecology, landscape, culture, and economy. Furthermore, a deep analysis is required of the theoretical basis of the urban water environment, which is associated with geographical location, landscape ecology, and a low-carbon economy. In this paper, we expound the main principles for constructing a system for the urban water environment (including sustainable development, ecological priority, and regional differences), and suggest the content of an urban water environmental system. Such a system contains a natural water environment, an economic water environment, and a social water environment. The natural water environment is the base, an effective economic water environment is the focus, and a healthy social water environment is the essence of such a system. The construction of an urban water environment should rely on a comprehensive security system, complete scientific theory, and advanced technology.

关键词：城市化发展现状工程管理施工管理

A tip clearance prediction model for multistage rotors and stators in aero-engines

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Chinese Journal of Aeronautics 2021年第2期34卷 343-357页

作者： huibin SUN Jing WANG Kai CHEN Huateng XIA Xin FENG Zhiyong chang Key Laboratory of High Performance Manufacturing for Aero Engine Ministry of Industry and Information TechnologyNorthwestern Poly technical UniversityXi'an 710072China AECC South Industry Company Limited Zhuzhou 412002China

Tip clearances of multistage rotors and stators greatly affect aero-engines’ aerodynamic efficiency, stability and safety. The inevitable machining and assembly errors, as well as the complicated error propagation mechanism, cause overproof or non-uniform tip clearances. However, it is generally accepted that tip clearances are difficult to predict, even under assembly state. In this paper, a tip clearance prediction model is proposed based on measured error data. Some 3 D error propagation sub-models, regarding rotors, supports and casings, are built and combined. The complex error coupling relationship is uncovered using mathematical methods. Rotor and stator tip clearances are predicted and analyzed in different phase angles. The maximum, minimum and average tip clearances can be calculated. The proposed model is implemented by a computer program,and a case study illustrates its performance and verifies its feasibility. The results can be referred by engineers in assembly quality judgement and decision-making.

关键词： Tip clearance Prediction Error propagation model Rotor and stator Aero-engine Assembly

Isothermal Oxidation Behavior of Dysprosium/S-Doped β-NiAl Alloys at 1200°C

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Journal of Materials Science & Technology 2014年第3期30卷 229-233页

作者： Lu Wang Dongqing Li Jian chang Hongbo Guo Shengkai Gong huibin Xu School of Materials Science and Engineering Beihang University AVIC Shenyang Liming Aero-engine Group Corporation Ltd.

A β--NiAI alloy with normal purity, a S-doped and a Dy and S co-doped （Y-NiAI alloys were prepared by arc-melting and their corresponding S contents were less than 20 ×10-6, 33 ×10-6 and 22 × 10-6, respectively. The isothermal oxidation behavior of the alloys at 1200 ℃ was investigated and the extent of S segregation at the scale-alloy interface was determined by scanning Auger microscopy. S-doping had no significant effect on the phase transformation rate from e- to β-Al2O3, while the addition of Dy retarded this process. For the S- doped alloy, scale rumpling occurred only after 2 h thermal exposure and numerous large voids were observed at the scale-alloy interface where S segregated. In contrast to this, the oxide scale formed on the Dy and S co-doped alloy still remained flat even after 50 h isothermal oxidation and only small voids existed at the interface where S segregation was not detected.

关键词： NiAl Dy S Isothermal oxidation Phase transformation Segregation

Epitranscriptomics and epiproteomics in cancer drug resistance:therapeutic implications

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Signal Transduction and Targeted Therapy 2020年第1期5卷 865-880页

作者： huibin Song Dongcheng Liu Shaowei Dong Leli Zeng Zhuoxun Wu Pan Zhao Litu Zhang Zhe-Sheng Chen chang Zou Shenzhen People’s Hospital(The Second Clinical Medical College Jinan UniversityThe First Affiliated HospitalSouthern University of Science and Technology)Shenzhen 518001 GuangdongChina College of Pharmacy and Health Sciences St.John’s UniversityQueens11439 New YorkUSA Tomas Lindahl Nobel Laureate Laboratory Research CentreThe Seventh Affiliated HospitalSun Yat-sen UniversityShenzhen 518107 GuangdongChina Department of Research Affiliated Tumor Hospital of Guangxi Medical UniversityNanning 530021 GuangxiChina Shenzhen Public Service Platform on Tumor Precision Medicine and Molecular Diagnosis Shenzhen 518001 GuangdongChina

Drug resistance is a major hurdle in cancer treatment and a key cause of poor prognosis.Epitranscriptomics and epiproteomics are crucial in cell proliferation,migration,invasion,and epithelial–mesenchymal transition.In recent years,epitranscriptomic and epiproteomic modification has been investigated on their roles in overcoming drug resistance.In this review article,we summarized the recent progress in overcoming cancer drug resistance in three novel aspects:(i)mRNA modification,which includes alternative splicing,A-to-I modification and mRNA methylation;(ii)noncoding RNAs modification,which involves miRNAs,lncRNAs,and circRNAs;and(iii)posttranslational modification on molecules encompasses drug inactivation/efflux,drug target modifications,DNA damage repair,cell death resistance,EMT,and metastasis.In addition,we discussed the therapeutic implications of targeting some classical chemotherapeutic drugs such as cisplatin,5-fluorouridine,and gefitinib via these modifications.Taken together,this review highlights the importance of epitranscriptomic and epiproteomic modification in cancer drug resistance and provides new insights on potential therapeutic targets to reverse cancer drug resistance.

关键词： therapeutic cancer drug