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Science China(Life Sciences) 2004年第3期47卷 279-286页

作者： ZHANG Wei feng Jiannan SHEN Beifen Beijing Basic Medical Institute Beijing 100850 China Beijing Basic Medical Institute Beijing 100850 China Beijing Basic Medical Institute Beijing 100850 China

The genes of the heavy and light chain variable region (VH, VL) of Z12 antibody against hTNF-a were cloned, and according to the translated sequence of amino acids, the spa-tial structures of VH and VL domains were modeled by using homology-based modeling method, followed by constructing the whole three-dimensional structure of Fv fragment. The complex model of Fv interacting with hTNF-a was gained with computer-guided molecular docking method, based on which, it was predicted that the epitope recognized by Z12 was from 141 to 146 of hTNF-a. hTNF-a molecule was divided into two fragments of N-terminal region from 1 to 91 and C-terminal region from 92 to 157 with prokaryotic expression. The measured results suggested that the antigenic epitope recognized by Z12 antibody was located in the C-terminal region 92-157 of hTNF-a, proving the predicted result reliable preliminarily. Further experimental results showed that after hTNF- 141-146 residues were deleted, Z12 antibody almost lost the ability to recognize the mutant, suggesting that the amino acid residues from 141 to 146 of hTNF-a were specially recognized by Z12 antibody.

关键词： human tumor necrosis factor-α, Fv, antigenic epitope, homology-based modeling, deletion.

Challenges in hydrogen adsorptions： from physisorption to chemisorption

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Frontiers of physics 2011年第2期6卷 142-150页

作者： feng DING Boris I. YAKOBSON Institute of Textile and Clothing Hong Kong Polytechnic University Kowloon Hong Kong China Department of Material Science and Mechanical Engineering Department of Chemistry Rice University Houston TX 77005 USA

In this short review, we will briefly discuss the story of hydrogen storage, its impact on clean energy application, especially the challenges of using hydrogen adsorption for onboard application. After a short comparison of the main methods of hydrogen storage （high pressure tank, metal hydride and adsorption）, we will focus our discussion on adsorption of hydrogen in graphitie carbon based large surface area adsorbents including carbon nanotubes, graphene and metal organic frameworks. The mechanisms, advantages, disadvantages and recent progresses will be discussed and reviewed for physisorption, metal-assisted storage and chemisorption. In the last section, we will discuss hydrogen spillover chemisorption in detail for the mechanism, status, challenges and perspectives. We hope to present a clear picture of the present technologies, challenges and the perspectives of hydrogen storage for the future studies.

关键词： hydrogen storage physisorption chemisorption spillover

Aerodynamic design optimization by using a continuous adjoint method

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Science China(Physics,Mechanics & Astronomy) 2014年第7期57卷 1363-1375页

作者： LUO JiaQi XIONG JunTao LIU feng College of Engineering Peking University Department of Mechanical and Aerospace Engineering University of California

This paper presents the fundamentals of a continuous adjoint method and the applications of this method to the aerodynamic design optimization of both external and internal *** formulation of the continuous adjoint equations and the corresponding boundary conditions are *** the adjoint method,the complete gradient information needed in the design optimization can be obtained by solving the governing flow equations and the corresponding adjoint equations only once for each cost function,regardless of the number of design *** inverse design of airfoil is firstly performed to study the accuracy of the adjoint gradient and the effectiveness of the adjoint method as an inverse design *** the method is used to perform a series of single and multiple point design optimization problems involving the drag reduction of airfoil,wing,and wing-body configuration,and the aerodynamic performance improvement of turbine and compressor blade *** results demonstrate that the continuous adjoint method can efficiently and significantly improve the aerodynamic performance of the design in a shape optimization problem.

关键词： continuous adjoint method aerodynamic design optimization transonic flow computational fluid dynamics aerospace engineering

Guided filter-based multi-scale super-resolution reconstruction

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CAAI Transactions on Intelligence Technology 2020年第2期5卷 128-140页

作者： Xiaomei feng Jinjiang Li Zhen Hua School of Electronic and Communications Engineering Shandong Technology and Business UniversityYantai 264005People’s Republic of China Co-innovation Center of Shandong Colleges and Universities:Future Intelligent Computing Shandong Technology and Business UniversityYantai 264005People’s Republic of China

The learning-based super-resolution reconstruction method inputs a low-resolution image into a network,and learns a non-linear mapping relationship between low-resolution and high-resolution through the *** this study,the multi-scale super-resolution reconstruction network is used to fuse the effective features of different scale images,and the non-linear mapping between low resolution and high resolution is studied from coarse to fine to realise the end-to-end super-resolution reconstruction *** loss of some features of the low-resolution image will negatively affect the quality of the reconstructed *** solve the problem of incomplete image features in low-resolution,this study adopts the multi-scale super-resolution reconstruction method based on guided image *** high-resolution image reconstructed by the multi-scale super-resolution network and the real high-resolution image are merged by the guide image filter to generate a new image,and the newly generated image is used for secondary training of the multi-scale super-resolution reconstruction *** newly generated image effectively compensates for the details and texture information lost in the low-resolution image,thereby improving the effect of the super-resolution reconstructed *** with the existing super-resolution reconstruction scheme,the accuracy and speed of super-resolution reconstruction are improved.

关键词： resolution image network

Shock control bump parametric research on supercritical airfoil

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Science China(Technological Sciences) 2011年第11期54卷 2935-2944页

作者： TIAN Yun LIU PeiQing feng PeiHua School of Aeronautics Science and Engineering Beihang University Beijing 100191 China

High precision of CFD code was used to study supercritical Airfoil RAE2822 superimposed with different shock control bumps under the transonic conditions.A successful improvement was made to current widely used Hicks-Henne functions which describe shock control *** on improving the airfoil's lift-drag ratio,the study shows that,(1) the best bump crest position is at the position close to 50% of bump chord,which is almost independent of free stream or pre-shock Mach numbers,but the bump height is highly coupled with the crest position,which means that the higher the bump is,the more obviously the crest position affects the airfoil lift-drag ratio,and it becomes more evident with the increase of free stream or pre-shock Mach numbers;(2) in case that the lift-drag ratio of airfoil with bump is higher than basic airfoil,almost all the optimum distances between bump crest and shock wave are close to 30% of bump chord;(3) almost all the lift-drag ratios of airfoil with bump increase as bump chord length increases,of which this trend becomes more evident as bump height increases;(4) with the increase of the bump height,almost all the lift-drag ratios of airfoil with bump decrease at low free stream or pre-shock Mach *** the Mach numbers are higher,the lift-drag ratio of airfoil increases as the increase of the bump height,and particularly,the trend tends to be visible when the Mach numbers are at a high level.

关键词： shock wave flow control transonic flow parametric supercritical airfoil

Strategies and Methods for Cloud Migration

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International Journal of Automation and computing 2014年第2期11卷 143-152页

作者： Jun-feng Zhao Jian-Tao Zhou College of Computer Science Inner Mongolia University

Legacy system migration to the cloud brings both great challenges and benefits, so there exist various academic research and industrial applications on legacy system migration to the cloud. By analyzing the research achievements and application status,we divide the existing migration methods into three strategies according to the cloud service models integrally. Different processes need to be considered for different migration strategies, and different tasks will be involved accordingly. The similarities and differences between the migration strategies are discussed, and the challenges and future work about legacy system migration to the cloud are proposed. The aim of this paper is to provide an overall presentation for legacy system migration to the cloud and identify important challenges and future research directions.

关键词： Migration legacy system cloud infrastructure as a service(IaaS) platform as a service(PaaS) software as a service(SaaS).

High-dimensional *** Problem over Short Intervals

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Acta Mathematica Sinica,English Series 2014年第2期30卷 213-228页

作者： Zhe feng XU Tian Ping ZHANG Department of Mathematics Northwest University College of Mathematics and Information Science Shaanxi Normal University

Letk be a positive integer and n a nonnegative integer,0 〈 λ1,...,λk＋1 ≤ 1 be real numbers and w =（λ1,λ2,...,λk＋1）.Let q ≥ max{[1/λi ]：1 ≤ i ≤ k ＋ 1} be a positive integer,and a an integer coprime to *** by N（a,k,w,q,n） the 2n-th moment of（b1··· bk c） with b1··· bk c ≡ a（mod q）,1 ≤ bi≤λiq（i = 1,...,k）,1 ≤ c ≤λk＋1 q and 2（b1＋ ··· ＋ bk ＋ c）.We first use the properties of trigonometric sum and the estimates of n-dimensional Kloosterman sum to give an interesting asymptotic formula for N（a,k,w,q,n）,which generalized the result of *** we use the properties of character sum and the estimates of Dirichlet L-function to sharpen the result of N（a,k,w,q,n） in the case ofw =（1/2,1/2,...,1/2） and n = *** order to show our result is close to the best possible,the mean-square value of N（a,k,q） φk（q）/2k＋2and the mean value weighted by the high-dimensional Cochrane sum are studied too.

关键词： D. H. Lehmer problem short intervals trigonometric sum character sum Cochrane sum

An Optimal Control Problem of a Coupled Nonlinear Parabolic Population System

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Acta Mathematicae Applicatae Sinica 2007年第3期23卷 377-388页

作者： Chao-hua Jia De-xing feng Department of Applied Mathematics LMIB of the Ministry of Education Beijing University of Aeronauticsand Astronautics Beijing 100083 China Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100080 China

An optimal control problem for a coupled nonlinear parabolic population system is considered. The existence and uniqueness of the positive solution for the system is shown by the method of upper and lower solutions. An explicit prior bound of solutions to the system is given by considering an auxiliary coupled linear system. The existence of the optimal control is proved and the characterization of the optimal control is established.

关键词： Nonlinear parabolic systems optimal control upper and lower solutions

Improving Diversity with Multi-Loss Adversarial Training in Personalized News Recommendation

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Computers, Materials & Continua 2024年第8期80卷 3107-3122页

作者： Ruijin Xue Shuang feng Qi Wang School of Computer and Cyber Sciences Communication University of ChinaBeijing100024China State Key Laboratory of Media Convergence and Communication Communication University of ChinaBeijing100024China

Users’interests are often diverse and multi-grained,with their underlying intents even more *** captur-ing users’interests and uncovering the relationships between diverse interests are key to news ***,diversity is an important metric for evaluating news recommendation algorithms,as users tend to reject excessive homogeneous information in their recommendation ***,recommendation models themselves lack diversity awareness,making it challenging to achieve a good balance between the accuracy and diversity of news *** this paper,we propose a news recommendation algorithm that achieves good performance in both accuracy and *** most existing works that solely optimize accuracy or employ more features to meet diversity,the proposed algorithm leverages the diversity-aware capability of the ***,we introduce an augmented user model to fully capture user intent and the behavioral guidance they might undergo as a ***,we focus on the relationship between the original clicked news and the augmented clicked ***,we propose an effective adversarial training method for diversity(AT4D),which is a pluggable component that can enhance both the accuracy and diversity of news recommendation *** experiments on real-world datasets confirm the efficacy of the proposed algorithm in improving both the accuracy and diversity of news recommendations.

关键词： News recommendation diversity accuracy data augmentation

The Upper Ordovician Microfossil Assemblages from the Pagoda Formation in Zigui, Hubei Province

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Journal of Earth Science 2018年第4期29卷 900-911页

作者： Ke Zhang Aihua Yuan Qinglai feng State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences School of Earth Sciences China University of Geosciences

The Pagoda Formation is a lithologically and biologically distinctive unit among the Upper Ordovician. The strata are characterized by a nodular limestone, which yields fossil assemblages of high diversity. Conodonts of 14 genera 20 species （6 undetermined species） and ostracods of 14 genera 26 species （16 undetermined species） are identified. In addition, spherical radiolarians and minute-walled foraminifers were first reported from this formation in South China. The conodont assemblage is attributed to the Hamarous europaeus Zone, which indicates the Early Katian Age. The conodont HDS biofacies, along with thin-shelled ostracods, spherical radiolarians and foraminifers, suggest relatively deep and quiet water depositional environment. Accordingly, these fossil materials not only enrich the diversity of the Pagoda biota, but also provide evidence for discussions of deposi- tional environments and stratigraphic correlations for the Pagoda Formation.

关键词： South China Ordovician conodont ostracod radiolarians foraminifer.