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Large-Scale Multi-Objective Optimization Algorithm Based on Weighted Overlapping Grouping of Decision Variables
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作者 Liang Chen Jingbo Zhang +2 位作者 Linjie Wu Xingjuan Cai Yubin Xu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第7期363-383,共21页
The large-scale multi-objective optimization algorithm(LSMOA),based on the grouping of decision variables,is an advanced method for handling high-dimensional decision variables.However,in practical problems,the intera... The large-scale multi-objective optimization algorithm(LSMOA),based on the grouping of decision variables,is an advanced method for handling high-dimensional decision variables.However,in practical problems,the interaction among decision variables is intricate,leading to large group sizes and suboptimal optimization effects;hence a large-scale multi-objective optimization algorithm based on weighted overlapping grouping of decision variables(MOEAWOD)is proposed in this paper.Initially,the decision variables are perturbed and categorized into convergence and diversity variables;subsequently,the convergence variables are subdivided into groups based on the interactions among different decision variables.If the size of a group surpasses the set threshold,that group undergoes a process of weighting and overlapping grouping.Specifically,the interaction strength is evaluated based on the interaction frequency and number of objectives among various decision variables.The decision variable with the highest interaction in the group is identified and disregarded,and the remaining variables are then reclassified into subgroups.Finally,the decision variable with the strongest interaction is added to each subgroup.MOEAWOD minimizes the interactivity between different groups and maximizes the interactivity of decision variables within groups,which contributed to the optimized direction of convergence and diversity exploration with different groups.MOEAWOD was subjected to testing on 18 benchmark large-scale optimization problems,and the experimental results demonstrate the effectiveness of our methods.Compared with the other algorithms,our method is still at an advantage. 展开更多
关键词 Decision variable grouping large-scale multi-objective optimization algorithms weighted overlapping grouping direction-guided evolution
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Overlapping infections of Mycobacterium canariasense and Nocardia farcinica in an immunocompetent patient:A case report
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作者 Hai-Yan Huang Kun-Peng Bu +1 位作者 Jin-Wei Liu Jing Wei 《World Journal of Clinical Cases》 SCIE 2024年第12期2079-2085,共7页
BACKGROUND Infections by non-tuberculous mycobacteria(NTM)have become more common in recent years.Mycobacterium canariasense(M.canariasense)was first reported as an opportunistic pathogen in 2004,but there have been v... BACKGROUND Infections by non-tuberculous mycobacteria(NTM)have become more common in recent years.Mycobacterium canariasense(M.canariasense)was first reported as an opportunistic pathogen in 2004,but there have been very few case reports since then.Nocardia is a genus of aerobic and Gram-positive bacilli,and these species are also opportunistic pathogens and in the Mycobacteriales order.Conventional methods for diagnosis of NTM are inefficient.Metagenomic next-generation sequencing(mNGS)can rapidly detect many pathogenic microorganisms,even rare species.Most NTM and Nocardia infections occur in immunocompromised patients with atypical clinical symptoms.There are no previous reports of infection by M.canariasense and Nocardia farcinica(N.farcinica),especially in immunocompetent patients.This case report describes an immunocompetent 52-year-old woman who had overlapping infections of M.canariasense,N.farcinica,and Candida parapsilosis(C.parapsilosis)based on mNGS.CASE SUMMARY A 52-year-old woman presented with a productive cough and chest pain for 2 wk,and recurrent episodes of moderate-grade fever for 1 wk.She received antibiotics for 1 wk at a local hospital,and experienced defervescence,but the productive cough and chest pain persisted.We collected samples of a lung lesion and alveolar lavage fluid for mNGS.The lung tissue was positive for M.canariasense,N.farcinica,and C.parapsilosis,and the alveolar lavage fluid was positive for M.canariasense.The diagnosis was pneumonia,and application of appropriate antibiotic therapy cured the patient.CONCLUSION Etiological diagnosis is critical for patients with infectious diseases.mNGS can identify rare and novel pathogens,and does not require a priori knowledge. 展开更多
关键词 overlapping infection Mycobacterium canariasense Nocardia farcinica Metagenomic next-generation sequencing technology Case report
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Analysis of Roadbed Splicing at Hub Interchanges
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作者 Lizhao Zhao Liang Liu 《Journal of World Architecture》 2024年第1期24-30,共7页
This article discusses the roadbed splicing for hub interchanges.The article starts with a description of the characteristics of junction roadbed splicing.The application of splicing technology is explained using a su... This article discusses the roadbed splicing for hub interchanges.The article starts with a description of the characteristics of junction roadbed splicing.The application of splicing technology is explained using a subgrade splicing scheme of a project.Roadbed splicing involves stepwise excavation and preparative measures like surface cleaning and backfilling.This article serves to provide a valuable reference for road and bridge construction and improve the quality of China’s road and bridge projects,so as to achieve sustainable development of the road and bridge engineering industry. 展开更多
关键词 Hub interchange roadbed splicing Construction preparation Stepwise excavation roadbed filling
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Settlement Control Standards of Construction and Expansion for Mountainous Highway Roadbeds
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作者 Zhipan Yang Wei Gan Haonan Ding 《Journal of Architectural Research and Development》 2024年第2期43-49,共7页
This article analyzes the differential settlement of new and old roadbeds after widening and its characteristics based on a highway reconstruction and expansion project case study.The research proposes a subgrade sett... This article analyzes the differential settlement of new and old roadbeds after widening and its characteristics based on a highway reconstruction and expansion project case study.The research proposes a subgrade settlement control standard that states that the maximum differential settlement value should be less than 5 cm when the embankment fill height exceeds 20 m.Similarly,the maximum differential settlement value should be less than 10 cm when the embankment fill height does not exceed 20 m.The findings of the study can provide a useful reference for the design of roadbed widening in highway reconstruction and expansion projects. 展开更多
关键词 Mountainous highway Reconstruction and expansion roadbed widening Settlement control
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Set pair three-way overlapping community discovery algorithm for weighted social internet of things 被引量:1
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作者 Chunying Zhang Jing Ren +3 位作者 Lu Liu Shouyue Liu Xiaoqi Li Liya Wang 《Digital Communications and Networks》 SCIE CSCD 2023年第1期3-13,共11页
There are many problems in Social Internet of Things(IoTs),such as complex topology information,different degree of association between nodes and overlapping communities.The idea of set pair information grain computin... There are many problems in Social Internet of Things(IoTs),such as complex topology information,different degree of association between nodes and overlapping communities.The idea of set pair information grain computing and clustering is introduced to solve the above problems so as to accurately describe the similarity between nodes and fully explore the multi-community structure.A Set Pair Three-Way Overlapping Community Discovery Algorithm for Weighted Social Internet of Things(WSIoT-SPTOCD)is proposed.In the local network structure,which fully considers the topological information between nodes,the set pair connection degree is used to analyze the identity,difference and reverse of neighbor nodes.The similarity degree of different neighbor nodes is defined from network edge weight and node degree,and the similarity measurement method of set pair between nodes based on the local information structure is proposed.According to the number of nodes'neighbors and the connection degree of adjacent edges,the clustering intensity of nodes is defined,and an improved algorithm for initial value selection of k-means is proposed.The nodes are allocated according to the set pair similarity between nodes and different communities.Three-way community structures composed of a positive domain,boundary domain and negative domain are generated iteratively.Next,the overlapping node set is generated according to the calculation results of community node membership.Finally,experiments are carried out on artificial networks and real networks.The results show that WSIoT-SPTOCD performs well in terms of standardized mutual information,overlapping community modularity and F1. 展开更多
关键词 Social internet of things Set pair analysis K-MEANS Local information structure overlapping community
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Stress distribution in roadbeds of slab tracks with longitudinal discontinuities
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作者 Qingzhi Ye Qiang Luo +2 位作者 Guishuai Feng Tengfei Wang Hongwei Xie 《Railway Engineering Science》 2023年第1期61-74,共14页
Stress concentration occurs in the foundations of railway tracks where discontinuous components are located.The exacerbated stress under the expansion joints in slab tracks may trigger foundation failures such as mud ... Stress concentration occurs in the foundations of railway tracks where discontinuous components are located.The exacerbated stress under the expansion joints in slab tracks may trigger foundation failures such as mud pumping.Although the higher stress due to the discontinuities of track structures has been discussed in past studies,few focused on the stress response of roadbeds in slab tracks and quantitatively characterized the stress pattern.In this paper,we performed a dynamic finite element analysis of a track-formation system,incorporating expansion joints as primary longitudinal discontinuities.The configurations of CRTS Ⅲ slab tracks and the contact conditions between concrete layers were considered.Numerical results show that longitudinal influencing length of induced stress on roadbed under wheel load relates to the contact conditions between concrete layers,increasing nonlinearly at a larger coefficient of friction.Given a measured coefficient of friction of 0.7,the calculated longitudinal influencing length(9.0 m) matches with field data.The longitudinal influencing length is not affected with the increasing velocity.As stress concentration arises with expansion joints,the worstcase scenario emerges when double-axle loads are exerted immediately above the expansion joints between concrete bases.A stress concentration factor Cvon the roadbed is proposed;it increases with the increasing velocity,changing from 1.33 to 1.52 at velocities between 5 and 400 km/h.The stress distribution on roadbeds transforms from a trapezoid pattern at continuous sections to a triangle pattern at points with longitudinal discontinuities.An explicit expression is finally proposed for the stress pattern on roadbed under expansion joints.Although structural discontinuities induce stress raiser,the extent of concentration is mitigated with increasing depth at different velocity levels. 展开更多
关键词 Ballastless track Expansion joint Dynamic stress roadbed Stress distribution
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Analysis of Highway Roadbed Performance Evaluation Technology
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作者 Yunyong Zhou Ke Tu +2 位作者 Daqing Wu Shuyan Liu Yingying Ye 《Journal of World Architecture》 2023年第2期36-40,共5页
With the continuous development of China,the requirements for road construction are also increasing.Among them,strengthening the performance of roadbed test can effectively improve road construction.Besides,it is also... With the continuous development of China,the requirements for road construction are also increasing.Among them,strengthening the performance of roadbed test can effectively improve road construction.Besides,it is also crucial to perform suitable tests in a timely manner.Therefore,highway inspection technology should be improved for the continuous development of highway construction,which will be explained in this paper,in hopes of improving the construction of highway in China. 展开更多
关键词 Highway roadbed Performance evaluation Testing technology
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Real-Time Mosaic Method of Aerial Video Based on Two-Stage Key Frame Selection Method
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作者 Minwen Yuan Yonghong Long Xin Li 《Open Journal of Applied Sciences》 2024年第4期1008-1021,共14页
A two-stage automatic key frame selection method is proposed to enhance stitching speed and quality for UAV aerial videos. In the first stage, to reduce redundancy, the overlapping rate of the UAV aerial video sequenc... A two-stage automatic key frame selection method is proposed to enhance stitching speed and quality for UAV aerial videos. In the first stage, to reduce redundancy, the overlapping rate of the UAV aerial video sequence within the sampling period is calculated. Lagrange interpolation is used to fit the overlapping rate curve of the sequence. An empirical threshold for the overlapping rate is then applied to filter candidate key frames from the sequence. In the second stage, the principle of minimizing remapping spots is used to dynamically adjust and determine the final key frame close to the candidate key frames. Comparative experiments show that the proposed method significantly improves stitching speed and accuracy by more than 40%. 展开更多
关键词 UAV Aerial Video Image Stiching Key Frame Selection overlapping Rate Remap Error
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EFFECT OF OVERLAPPING TREATMENT ON MICROSTRUCTURE OF LASER-CLAD WC/Ni60A COMPOSITE COATING 被引量:6
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作者 C.Z. Chen 1,2) , X.D. Liu 3) , S.J. Zhang 4) , D.W. Cui 1) , T.Q. Lei 2) and J.H. Yu 1) 1) College of Material Science and Technology, Shandong University of Technology, Jinan 250061, China 2) College of Material Science and T 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 1999年第5期1014-1018,共5页
The effect of overlapping treatment on microstructure of laser clad WC/Ni60A composite coating was studied with XRD, SEM, TEM and SAED etc. The results show that during the overlapping treatment the existence of the r... The effect of overlapping treatment on microstructure of laser clad WC/Ni60A composite coating was studied with XRD, SEM, TEM and SAED etc. The results show that during the overlapping treatment the existence of the residual heat and edge angle effect on the substrate has changed the composition and microstructure of the coating by raising the fusion temperature and increasing the dilution degree of the coating. 展开更多
关键词 LASER CLADDING WC/Ni60A MICROSTRUCTURE overlapping edge angle EFFECT
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Biomathematical study of time-dependent flow of a Carreau nanofluid through inclined catheterized arteries with overlapping stenosis 被引量:6
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作者 Ashfaq Ahmed Sohail Nadeem 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第11期2725-2744,共20页
This work is concerned with the analysis of blood flow through inclined catheterized arteries having a balloon(angioplasty) with time-variant overlapping stenosis. The nature of blood in small arteries is analyzed mat... This work is concerned with the analysis of blood flow through inclined catheterized arteries having a balloon(angioplasty) with time-variant overlapping stenosis. The nature of blood in small arteries is analyzed mathematically by considering it as a Carreau nanofluid. The highly nonlinear momentum equations of nanofluid model are simplified by considering the mild stenosis case. The formulated problem is solved by a homotopy perturbation expansion in terms of a variant of the Weissenberg number to obtain explicit forms for the axial velocity, the stream function, the pressure gradient, the resistance impedance and the wall shear stress distribution. These solutions depend on the Brownian motion number, thermophoresis number, local temperature Grashof number G_r and local nanoparticle Grash of number B_r. The results were also studied for various values of the physical parameters, such as the Weissenberg number W_i, the power law index n, the taper angle φ, the maximum height of stenosis δ~*, the angle of inclination α, the maximum height of balloon σ~*, the axial displacement of the balloon z_d~*,the flow rate F and the Froud number Fr. The obtained results show that the transmission of axial velocity curves through a Newtonian fluid(Wi=0, n=1, Gr=0, Br=0, Nt=0, Nb≠0) is substantially lower than that through a Carreau nanofluid near the wall of balloon while the inverse occurs in the region between the balloon and stenosis. The streamlines have a clearly distinguished shifting toward the stenotic region and this shifting appears near the wall of the balloon, while it has almost disappeared near the stenotic wall and the trapping bolus in the case of horizontal arteries and Newtonian fluid(Wi=0, n=1, Gr=0, Br=0, Nt=0, Nb≠0) does not appear but for the case of Carreau nanofluid bolus appears. 展开更多
关键词 overlapping stenosed artery NANofLUID Grashof number BROWNIAN motion THERMOPHORESIS pharmacology
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Effect of Interface Friction on Overlapping Sheets Bulging Formability and Microstructure of 5A02 Aluminum Alloy 被引量:3
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作者 高铁军 YAO Yongjie +1 位作者 WANG Xiaokang SHAO Ruowei 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2019年第4期919-924,共6页
Aluminum alloy 5 A02 with low plasticity was used as target sheet, and stainless steel SUS304 with good plasticity was used as overlapping sheet to investigate the effect of interface friction on bulging formability a... Aluminum alloy 5 A02 with low plasticity was used as target sheet, and stainless steel SUS304 with good plasticity was used as overlapping sheet to investigate the effect of interface friction on bulging formability and microstructure of target sheet in overlapping sheets bulging process. Sheet sliding experiment was performed to measure interface friction coefficient of 5 A02/SUS304 in different lubricating conditions and normal pressure. Overlapping sheets bulging experiment of 5 A02/SUS304 was carried out to investigate the influence of interface friction on limit bulging height, wall thickness distribution, microstructure and fracture morphology of 5 A02 bulging specimens. The results showed that increase of the interface friction coefficient of 5 A02/SUS304 could effectively improve the limit bulging height and deformation uniformity of 5 A02. And the fracture style of 5 A02 transformed from toughness fracture of dimples-micropores gathered to fault slip separation fracture. Therefore, target sheet bulging formability is improved with the increase of interface friction coefficient. 展开更多
关键词 overlapping SHEETS FORMING friction coefficient FORMABILITY MICROSTRUCTURE
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Estimation method for parameters of overlapping nuclear pulse signal 被引量:1
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作者 Hong-Quan Huang Xiao-Feng Yang +1 位作者 Wei-Cheng Ding Fang Fang 《Nuclear Science and Techniques》 SCIE CAS CSCD 2017年第1期80-87,共8页
Identification of nuclear pulse signal is of importance in radioactive measurements,especially in recognizing adjacent overlapping nuclear pulses.In this article,we propose an estimation method for parameters of typic... Identification of nuclear pulse signal is of importance in radioactive measurements,especially in recognizing adjacent overlapping nuclear pulses.In this article,we propose an estimation method for parameters of typical overlapping nuclear pulse signals.First,the nuclear pulses are regarded as individual genes and the norm is set as the fitness function.Second,the global optimal solution is found by searching the population of genetic algorithm,so as to estimate the parameters of nuclear pulse.With high precision,this method can identify parameters of overlapping nuclear pulses in the Sallen-Key Gaussian signal decomposition experiments.This pulse recognition method is of great significance to improve the precision of radioactive measurement and is suitable for serious overlap of nuclear pluses. 展开更多
关键词 NUCLEAR PULSE overlapping PARAMETER IDENTIFICATION
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Host markers and correlated mutations in the overlapping genes of influenza viruses: M1, M2;NS1, NS2;and PB1, PB1-F2 被引量:7
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作者 Wei Hu 《Natural Science》 2010年第11期1225-1246,共22页
The influenza A viruses have three gene segments, M, NS, and PB1, which code for more than one protein. The overlapping genes from the same segment entail their interdependence, which could be reflected in the evoluti... The influenza A viruses have three gene segments, M, NS, and PB1, which code for more than one protein. The overlapping genes from the same segment entail their interdependence, which could be reflected in the evolutionary constraints, host distinction, and co-mutations of influenza. Most previous studies of overlapping genes focused on their unique evolutionary constraints, and very little was achieved to assess the potential impact of the overlap on other biological aspects of influenza. In this study, our aim was to explore the mutual dependence in host differentiation and co-mutations in M, NS, and PB1 of avian, human, 2009 H1N1, and swine viruses, with Random Forests, information entropy, and mutual information. The host markers and highly co-mutated individual sites and site pairs (P values < 0.035) in the three gene segments were identified with their relative significance between the overlapping genes calculated. Further, Random Forests predicted that among the three stop codons in the current PB1-F2 gene of 2009 H1N1, the significance of a mutation at these sites for host differentiation was, in order from most to least, that at 12, 58, and 88, i.e., the closer to the start of the gene the more important the mutation was. Finally, our sequence analysis surprisingly revealed that the full-length PB1-F2, if the three stop codons were all mutated, would function more as a swine protein than a human protein, although the PB1 of 2009 H1N1 was derived from human H3N2. 展开更多
关键词 2009 H1N1 Co-Mutation Correlation HOST Marker INFLUENZA INFORMATION Entropy Mutual INFORMATION MUTATION overlapping Genes Random Forests
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Community discovery method with uncertainty measure of overlapping nodes based on topological potential 被引量:1
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作者 张健沛 李泓波 +3 位作者 杨静 白劲波 初妍 张乐君 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2012年第2期16-22,共7页
Community discovery of complex networks,esp.of social networks,has been a hotly debated topic in academic circles in recent years.Since actual networks usually contain some overlapping nodes that are difficult to assi... Community discovery of complex networks,esp.of social networks,has been a hotly debated topic in academic circles in recent years.Since actual networks usually contain some overlapping nodes that are difficult to assign to a certain community,overlapping community discovery is under great demand in practical applications.However,at present network community discovery is mainly done by non-overlapping community discovery methods,overlapping discovery methods are not common.In this context,an overlapping community discovery method is proposed hereby based on topological potential and specific algorithms are also provided.This method not only considers the spread of the uncertainty of community identity of the overlapping nodes in the network,but also realizes a quantified representation,i.e.,uncertainty measure,of the community identity of the overlapping nodes.The experiment results show that this method yields the results that are consistent with those by the classic methods and are more reasonable. 展开更多
关键词 social NETWORK complex NETWORK overlapping COMMUNITY discovery uncertainty MEASURE TOPOLOGICAL potential
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Fully Bayesian reliability assessment of multi-state systems with overlapping data 被引量:1
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作者 Zhipeng Hao Jianbin Guo Shengkui Zeng 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2017年第1期187-198,共12页
The failure data at the system level are often limited,resulting in high uncertainty to system reliability assessment. Integrating data drawn from various structural levels of the target system(e.g. the system, subsys... The failure data at the system level are often limited,resulting in high uncertainty to system reliability assessment. Integrating data drawn from various structural levels of the target system(e.g. the system, subsystems, assemblies and components), i.e. the multi-level data, through Bayesian analysis can improve the precision of system reliability assessment. However, if the multi-level data are overlapping, it is challenging for Bayesian integration to develop the likelihood function. Especially for multistate systems(MSS), the Bayesian integration with overlapping data is even more difficult. The major disadvantage of previous approaches is the intensive computation for the development of the likelihood function caused by the workload to opt the appropriate combinations of the vectors of component states consistent with the overlapping data. An improved fully Bayesian integration approach from a geometric perspective is proposed for the reliability assessment of MSS with overlapping data. In this method, a specific combination of component states is regarded as a state vector, which leads to a specific system state of the MSS, and all state vectors generate a system state space. The overlapping data are regarded as the constraints which create hyperplanes in the system state space. And a point in a hyperplane corresponds to a particular combination of the state vectors. In the light of the features of the constraints, the proposed approach introduces space partition and hyperplane segmentation, which reduces the selection workload significantly and simplifies the likelihood function for overlapping data. Two examples demonstrate the feasibility and efficiency of the proposed approach. 展开更多
关键词 BAYESIAN INTEGRATION overlapping DATA MULTI-STATE systems
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Identification of the immunogenic domains in HBsAg preS1 region using overlapping preS1 fragment fusion proteins 被引量:7
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作者 Wei-GuoHu JunWei Heng-ChuanXia Xin-XiuYang FengLi Guang-DiLi YuanWang Zu-ChuanZhang 《World Journal of Gastroenterology》 SCIE CAS CSCD 2005年第14期2088-2094,共7页
AIM: The incorporation of hepatitis B virus (HBV) preS1 region into epitope-based vaccines against HBV has been accepted widely, but the incorporate site and size of preS1 sequence is controversial. Therefore our purp... AIM: The incorporation of hepatitis B virus (HBV) preS1 region into epitope-based vaccines against HBV has been accepted widely, but the incorporate site and size of preS1 sequence is controversial. Therefore our purpose was to further investigate its immunogenic domains for the epitopebased hepatitis B vaccine design.METHODS: Eight GST fusion proteins containing overlapping preS1 fragments in preS1 (21-119) region were expressed in E.coli. Using these purified fusion proteins, the immunogenic domains in preS1 region were identified in detail in mice and humans by Western blot analysis and ELISA.RESULTS: The results in mice showed that the immunogenic domains mainly existed in preS1 (21-59) and preS1 (95-109). Similarly, these fragments had strong immunogenicity in humans; whereas the other parts except for preS1 (60-70) also had some immunogenicity.More importantly, a major immunogenic domain, preS1 (34-59), which has much stronger immunogenicity, was identified. Additionally, the antibodies against some preS1 fragments, especially preS1 (34-59), were speculated to be virus-neutralizing.CONCLUSION: Eight GST fusion proteins containing overlapping preS1 fragments were prepared successfully. They were used for the study on the immunogenic domains in preS1 (21-119) region. The preS1 (34-59) fragments were the major immunogenic domains in the preS1 region, and the antibodies against these fragments were speculated to be virus-neutralizing. Therefore, the incorporation of preS1 (34-59) fragments into epitopebased HBV vaccines may be efficient for enhancement of immune response. Additionally, the results also imply that there are more complex immune responses to preS1 region and more abundant immunogenic domains in humans. 展开更多
关键词 免疫原性 乙型肝炎病毒 疫苗接种 PRES1 溶解蛋白 基因序列
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Research on overlapping structures and evolution properties of co-citation network 被引量:2
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作者 Shiji CHEN Xiaolin ZHANG 《Chinese Journal of Library and Information Science》 2013年第1期1-13,共13页
Purpose: This paper intends to explore methodologies and indicators for the analysis of overlapping structures and evolution properties in a co-citation network, and provide reference for overlapping structure analysi... Purpose: This paper intends to explore methodologies and indicators for the analysis of overlapping structures and evolution properties in a co-citation network, and provide reference for overlapping structure analysis of other scientific networks.Design/methodology/approach: The Q-value variance is defined to achieve overlapping structures of different levels in the scientific networks. At the same time, analyses for time correlation variance and subject correlation variance are used to present the formation of overlapping structures in scientific networks. As a test, a co-citation network of highly cited papers on Molecular Biology & Genetics from Essential Science Indicator(ESI) is taken as an example for an empirical analysis.Findings: Our research showed that the Q-value variance is effective for achieving the desired overlapping structures. Meanwhile, the time correlation variance and subject correlation variance are equally useful for uncovering the evolution progress of scientific research, and the properties of overlapping structures in the research of co-citation network as well.Research limitations: In this paper, the theoretical analysis and verification of time and subject correlation variances are still at its initial stage. Further studies in this regard need to take actual evolution of research areas into consideration.Practical implications: Evolution properties of overlapping structures pave the way for overlapping and evolution analysis of disciplines or areas, this study is of practical value for the planning of scientific and technical innovation.Originality/value: This paper proposes an analytical method of time correlation variance and subject correlation variance based on the evolution properties of overlapping structures, which would provide the foundation for the evolution analysis of disciplines and interdisciplinary research. 展开更多
关键词 overlapping STRUCTURE Co-citation NETWORK Q-VALUE
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FEM SIMULATION OF RESIDUAL STRESSES INDUCED BY LASER SHOCK WITH OVERLAPPING LASER SPOTS 被引量:9
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作者 Y.X. Hu Z.Q. Yao 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2008年第2期125-132,共8页
有限元素方法被介绍在激光吃惊处理对待的材料达到剩余压力地的数字模拟。单个激光震动与方形、圆的激光点产生的剩余压力的分发被试验性的结果预言并且验证。与有限元素方法(女性) 模型,不同重叠率的效果和剩余压力的分发上的影响序... 有限元素方法被介绍在激光吃惊处理对待的材料达到剩余压力地的数字模拟。单个激光震动与方形、圆的激光点产生的剩余压力的分发被试验性的结果预言并且验证。与有限元素方法(女性) 模型,不同重叠率的效果和剩余压力的分发上的影响序列被模仿。结果显示那:(1 ) 重叠激光吃惊能增加压缩剩余压力。然而,它不在塑料的生长上是有效的结盟影响深度;(2 ) 重叠率应该为大区域处理小心地被优化并且选择。适当重叠率是有益的获得一块同类的剩余压力地;(3 ) 影响顺序在剩余压力地上有大效果。获得一块同类的剩余压力地能极大地稀释“剩余压力洞”的现象。 展开更多
关键词 模拟技术 残余压力 激光 有限元分析 金属材料
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Numerical simulation of roadbed slope under seismic action in permafrost regions 被引量:1
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作者 JingYu Liu JianKun Liu +2 位作者 ZhongQin Su Li Liu Min Xie 《Research in Cold and Arid Regions》 CSCD 2013年第5期540-547,共8页
The deformation and strength characteristics of roadbed slope under seismic loading in permafrost regions are simulated numerically. The seismic response of roadbed at different positions and inclinations of a slope s... The deformation and strength characteristics of roadbed slope under seismic loading in permafrost regions are simulated numerically. The seismic response of roadbed at different positions and inclinations of a slope section was analyzed.Results show that, roadbed slope damage is mainly led by lateral displacement, and the deformation gradually decreases with increasing depth; roadbed and foundation displacement and plastic strain increases with the magnitude of slope angle,hence the roadbed safety factor will be reduced. 展开更多
关键词 路基边坡 多年冻土区 数值模拟 地震作用 横向位移 强度特性 地震荷载 地震响应
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Destabilization analysis of overlapping underground chambers induced by blasting vibration with catastrophe theory 被引量:9
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作者 闫长斌 徐国元 左宇军 《中国有色金属学会会刊:英文版》 EI CSCD 2006年第3期735-740,共6页
According to the main characters of overlapping underground chambers, the roof (floor) of two adjacent underground chambers is simplified to the mechanical model that is the beam with build-in ends. And vibration load... According to the main characters of overlapping underground chambers, the roof (floor) of two adjacent underground chambers is simplified to the mechanical model that is the beam with build-in ends. And vibration load due to blasting is simplified to harmonic wave. The catastrophic model of double cusp for underground chambers destabilization induced by blasting vibration has been established under the circumstances of considering deadweight of the beam, and the condition of destabilization has been worked out. The critical safety thickness of the roof (floor) of underground chambers has been confirmed according to the destabilization condition. The influence of amplitude and frequency of blasting vibration load on the critical safety thickness has been analyzed, and the quantitative relation between velocity, frequency of blasting vibration and critical safety thickness has been determined. Research results show that the destabilization of underground chambers is not only dependent on the amplitude and frequency of blasting vibration load, but also related to deadweight load and intrinsic attribute. It is accordant to testing results and some related latest research results of blasting seismic effect. With increasing amplitude, the critical safety thickness of underground chambers decreases gradually. And the possibility of underground chambers destabilization increases. When the frequency of blasting vibration is equal to or very close to the frequency of beam, resonance effect will take place in the system. Then the critical safety thickness will turn to zero, underground chambers will be damaged severely, and its loading capacity will lose on the whole. 展开更多
关键词 爆破振动 地下开采 扰动 突变理论 临界安全厚度
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