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Gradient-based compressive image fusion

Yang CHEN,Zheng QIN

《信息与电子工程前沿（英文）》 2015年 第16卷 第3期   页码 227-237 doi: 10.1631/FITEE.1400217

摘要： We present a novel image fusion scheme based on gradient and scrambled block Hadamard ensemble (SBHE) sampling for compressive sensing imaging. First, source images are compressed by compressive sensing, to facilitate the transmission of the sensor. In the fusion phase, the image gradient is calculated to reflect the abundance of its contour information. By compositing the gradient of each image, gradient-based weights are obtained, with which compressive sensing coefficients are achieved. Finally, inverse transformation is applied to the coefficients derived from fusion, and the fused image is obtained. Information entropy (IE), Xydeas’s and Piella’s metrics are applied as non-reference objective metrics to evaluate the fusion quality in line with different fusion schemes. In addition, different image fusion application scenarios are applied to explore the scenario adaptability of the proposed scheme. Simulation results demonstrate that the gradient-based scheme has the best performance, in terms of both subjective judgment and objective metrics. Furthermore, the gradient-based fusion scheme proposed in this paper can be applied in different fusion scenarios.

关键词： Compressive sensing (CS)     Image fusion     Gradient-based image fusion     CS-based image fusion    

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Design of an enhanced visual odometry by building and matching compressive panoramic landmarks online

Wei LU,Zhi-yu XIANG,Ji-lin LIU

《信息与电子工程前沿（英文）》 2015年 第16卷 第2期   页码 152-165 doi: 10.1631/FITEE.1400139

摘要： Efficient and precise localization is a prerequisite for the intelligent navigation of mobile robots. Traditional visual localization systems, such as visual odometry (VO) and simultaneous localization and mapping (SLAM), suffer from two shortcomings: a drift problem caused by accumulated localization error, and erroneous motion estimation due to illumination variation and moving objects. In this paper, we propose an enhanced VO by introducing a panoramic camera into the traditional stereo-only VO system. Benefiting from the 360° field of view, the panoramic camera is responsible for three tasks: (1) detecting road junctions and building a landmark library online; (2) correcting the robot’s position when the landmarks are revisited with any orientation; (3) working as a panoramic compass when the stereo VO cannot provide reliable positioning results. To use the large-sized panoramic images efficiently, the concept of compressed sensing is introduced into the solution and an adaptive compressive feature is presented. Combined with our previous two-stage local binocular bundle adjustment (TLBBA) stereo VO, the new system can obtain reliable positioning results in quasi-real time. Experimental results of challenging long-range tests show that our enhanced VO is much more accurate and robust than the traditional VO, thanks to the compressive panoramic landmarks built online.

关键词： Visual odometry     Panoramic landmark     Landmark matching     Compressed sensing     Adaptive compressive feature    

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Asymmetric transfer hydrogenation of prochiral ketone catalyzed over Fe-CS/SBA-15 catalyst

XUE Ping, WU Tao

《化学科学与工程前沿（英文）》 2007年 第1卷 第3期   页码 251-255 doi: 10.1007/s11705-007-0045-1

摘要： A heterogeneous chiral catalyst Fe(III)-CS (chitosan) complex/mesoporous molecular sieve SBA-15 (Santa Barbara Amorphous) was prepared. The asymmetric transfer hydrogenations of prochiral acetophenone and 4-methyl-2-pentanone to corresponding chiral alcohols were carried out on Fe-CS/SBA-15 at atmosphere pressure using 2-propanol as hydrogen donor. Effects of Fe content in catalyst, reaction temperature, reaction time and promoter KOH concentration on the conversion of substrates and enantioselectivity were investigated. Fe-CS/SBA-15 with 2.2% mass fraction Fe exhibits considerable enantioselectivity and catalytic activity for the asymmetric transfer hydrogenations of aromatic ketone and aliphatic ketone. Under optimal reaction conditions: KOH concentration 0.03 mol/L, reaction temperature 70ºC and reaction time 4 h, enantiomer excess (ee) of ()-1-phenylethanol and conversion of acetophenone can reach 87.4% and 27.7%, respectively. Under the above KOH concentration and reaction temperature and reaction time of 8 h, the ee of ()-4-methyl-2-pentanol and conversion 4-methyl-2-pentanone amounted to 50.2% and 25.5%, respectively.

关键词： asymmetric transfer     enantioselectivity     Fe-CS/SBA-15     aliphatic     aromatic    

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预腐蚀后拉伸超载对LC4CS铝合金疲劳性能的影响

蒋荟,杨晓华

《中国工程科学》 2006年 第8卷 第2期   页码 44-46

摘要：

采用预腐蚀后进行单次拉伸超载疲劳试验的方法，研究了腐蚀与超载对LC4CS材料疲劳寿命的影响。

关键词： LC4CS 铝合金     预腐蚀     超载     疲劳寿命    

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The ITZ microstructure, thickness, porosity and its relation with compressive and flexural strength of

《结构与土木工程前沿（英文）》 2022年 第16卷 第2期   页码 191-201 doi: 10.1007/s11709-021-0792-y

摘要： A new insight into the interfacial transition zone (ITZ) in cement mortar specimens (CMSs) that is influenced by cement fineness is reported. The importance of cement fineness in ITZ characterizations such as morphology and thickness is elucidated by backscattered electron images and by consequences to the compressive (Fc) and flexural strength (Ff), and porosity at various water/cement ratios. The findings indicate that by increasing the cement fineness the calcium silicate hydrate formation in the ITZ is favored and that this can refine the pore structures and create a denser and more homogeneous microstructure. By increasing cement fineness by about 25% of, the ITZ thickness of CMSs was reduced by about 30% and Fc was increased by 7%–52% and Ff by 19%–40%. These findings illustrate that the influence of ITZ features on the mechanical strength of CMSs is mostly related to the cement fineness and ITZ microstructure.

关键词： cement fineness     interfacial transition zone     compressive and flexural strength    

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Sediment environmental capacity of 137Cs in Daya Bay

ZHANG Junli, CHEN Jiajun, XU Jialin, LI Yuanxin, HUANG Naiming

《环境科学与工程前沿（英文）》 2007年 第1卷 第2期   页码 202-206 doi: 10.1007/s11783-007-0035-z

摘要： Sediment environmental capacity of pollutants is very important for marine environmental management. Based on the methodology of a study on water, soil environmental capacity, and mass conservation theory in a system, the concept and model on sediment environmental capacity for Cs in Daya Bay were developed. The static capacity for Cs in the upper sediment near the shore at a shallow area was calculated, and the annual dynamic capacity and total dynamic capacity were also calculated through determination of the typical biomass in the sediment. The results showed that the estimated environmental capacity for Cs in sediments was approximately equal to the current input of Cs into the sediments. Controlling the input of Cs in the sediments within the environmental capacity guarantees the sustainability of the current situation of the Daya Bay ecosystem and avoidance of a significant degradation of the system.

关键词： concept     Sediment environmental     conservation theory     significant degradation     ecosystem    

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Analytical algorithms of compressive bending capacity of bolted circumferential joint in metro shield

《结构与土木工程前沿（英文）》   页码 901-914 doi: 10.1007/s11709-023-0915-8

摘要： The integrity and bearing capacity of segment joints in shield tunnels are associated closely with the mechanical properties of the joints. This study focuses on the mechanical characteristics and mechanism of a bolted circumferential joint during the entire bearing process. Simplified analytical algorithms for four stress stages are established to describe the bearing behaviors of the joint under a compressive bending load. A height adjustment coefficient, α, for the outer concrete compression zone is introduced into a simplified analytical model. Factors affecting α are determined, and the degree of influence of these factors is investigated via orthogonal numerical simulations. The numerical results show that α can be specified as approximately 0.2 for most metro shield tunnels in China. Subsequently, a case study is performed to verify the rationality of the simplified theoretical analysis for the segment joint via numerical simulations and experiments. Using the proposed simplified analytical algorithms, a parametric investigation is conducted to discuss the factors affecting the ultimate compressive bending capacity of the joint. The method for optimizing the joint flexural stiffness is clarified. The results of this study can provide a theoretical basis for optimizing the design and prediciting the damage of bolted segment joints in shield tunnels.

关键词： shield tunnel     segment joint     joint structural model     failure mechanism    

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Optimizing the compressive strength of concrete containing micro-silica, nano-silica, and polypropylene

Fatemeh ZAHIRI, Hamid ESKANDARI-NADDAF

《结构与土木工程前沿（英文）》 2019年 第13卷 第4期   页码 821-830 doi: 10.1007/s11709-019-0518-6

摘要： Many studies have evaluated the effects of additives such as nano-silica (NS), micro-silica (MS) and polymer fibers on optimizing the mechanical properties of concrete, such as compressive strength. Nowadays, with progress in cement industry provides, it has become possible to produce cement type I with strength classes of 32.5, 42.5, and 52.5 MPa. On the one hand, the microstructure of cement has changed, and modified by NS, MS, and polymers; therefore it is very important to determine the optimal percentage of each additives for those CSCs. In this study, 12 mix designs containing different percentages of MS, NS, and polymer fibers in three cement strength classes(CSCs) (32.5, 42.5, and 52.5 MPa) were designed and constructed based on the mixture method. Results indicated the sensitivity of each CSCs can be different on the NS or MS in compressive strength of concrete. Consequently, strength classes have a significant effect on the amount of MS and NS in mix design of concrete. While, polymer fibers don’t have significant effect in compressive strength considering CSCs.

关键词： mixture method     compressive strength     nano-silica     micro-silica     polypropylene fibers    

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基于质量感知的水下图像自适应压缩方法 Regular Papers

Ya-qiong CAI, Hai-xia ZOU, Fei YUAN

《信息与电子工程前沿（英文）》 2019年 第20卷 第5期   页码 716-730 doi: 10.1631/FITEE.1700737

摘要： 水下图像压缩是水声图像传输系统中必不可少并且至关重要的一个环节，有效的预测感知压缩图像的质量能使系统在压缩过程更好的调整压缩率，提高图像传输通信系统的效率。本文首先分别对压缩感知和嵌入式编码两种压缩策略下的水下压缩图像进行质量感知，然后利用图像活动性IAM（Image Activity Measurement）与BPP-SSIM（Bits Per Pixel and Structural SIMilarity）曲线间的映射进行建模并获得模型参数，从而根据图像的空域活动性、压缩率和压缩策略预测图像的压缩质量。实验结果表明本文所建立的模型能有效拟合水下图像的压缩质量曲线，根据模型中参数所具有的规律性能在小误差范围内预测出水下压缩图像的感知质量。本文所提出的方法能够有效的预测感知水下图像的压缩质量，并有效权衡压缩率与压缩质量之间的关系，减小发送端的数据缓存压力，提高水下图像通信系统的效率。

关键词： 水下图像压缩；SPIHT压缩；压缩感知；压缩质量预测    

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基于Wilkinson矩阵提升稀疏自适应匹配追踪重构效率 None

Rasha SHOITAN, Zaki NOSSAIR, I. I. IBRAHIM, Ahmed TOBAL

《信息与电子工程前沿（英文）》 2018年 第19卷 第4期   页码 503-512 doi: 10.1631/FITEE.1601588

摘要： 将块压缩感知（block compressive sensing，BCS）思想与SAMP技术结合，以提高SAMP技术性能。

关键词： 块压缩传感；稀疏自适应匹配追踪；贪婪算法；Wilkinson矩阵    

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All-inorganic TiO/CsAgBiBr composite as highly efficient photocatalyst under visible light irradiation

《化学科学与工程前沿（英文）》 2023年 第17卷 第12期   页码 1925-1936 doi: 10.1007/s11705-023-2344-6

摘要： In recent years, limited photocatalysis efficiency and wide band gap have hindered the application of TiO2 in the field of photocatalysis. A leading star in photocatalysis has been revealed as lead-free Cs2AgBiBr6 double halide perovskite nanocrystals, owing to its strong visible light absorption and tunable band gap. In this work, this photocatalytic process was facilitated by a unique TiO2/Cs2AgBiBr6 composite, which was identified as an S-cheme heterojunction. TiO2/Cs2AgBiBr6 composite was investigated for its structure and photocatalytic behavior. The results showed that when the perovskite dosage is 40%, the photocatalytic rate of TiO2 could be boosted to 0.1369 min–1. This paper discusses and proposes the band gap matching, carrier separation, and photocatalytic mechanism of TiO2/Cs2AgBiBr6 composites, which will facilitate the generation of new ideas for improving TiO2’s photocatalytic performance.

关键词： Cs2AgBiBr6 nanocrystals     visible-light photocatalyst     Cs2AgBiBr6/TiO2 heterojunction    

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evaluation of heavy metal contamination of sediment in Lake Dianchi by using modified AHP method and Cs

ZHANG Yan, GAO Xiang, ZHONG Zhenyu, PENG Buzhuo, DENG Xihai

《环境科学与工程前沿（英文）》 2008年 第2卷 第3期   页码 370-379 doi: 10.1007/s11783-008-0054-4

摘要： Through the use of general sampling and measurement by Cs dating, problems regarding the absence of monitoring data can easily be resolved. Further, weighted values need to be determined while Environment Quality Comprehensive Index (EQCI) is commonly used as applied in environmental quality comprehensive evaluation. In order to overcome the subjectivity in determining weights, the modified Analytical Hierarchy Process (AHP) method was designed. The modified AHP method involved the following key procedures: First, the parameters and were calculated based on the monitoring data; second, the factors were put in order according to the symbol and value of and ; third, the continuous odd integers, which represented the importance of factors, were given to factors according to their seating order; and, fourth, the factor weights were determined from the pair-wise comparison matrix calculated by the ratio of the given odd integers. Therefore, the weights were completely based on the monitoring data. In the present study, the comprehensive quality of sediments in five sections of Lake Dianchi were evaluated and the results indicated that the current contamination of sediments in each lake section is much more serious than at any other time in history.

关键词： Dianchi     Analytical Hierarchy     monitoring     modified Analytical     importance    

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Time- and temperature-dependence of compressive and tensile behaviors of polypropylene fiber-reinforced

《结构与土木工程前沿（英文）》 2021年 第15卷 第4期   页码 1025-1037 doi: 10.1007/s11709-021-0741-9

摘要： The understanding of compressive and tensile behaviors of polypropylene fiber-reinforced cemented paste backfill (FR-CPB) play crucial roles in the successful implementation of reinforcement technique in underground mine backfilling operations. However, very limited studies have been performed to gain insight into the evolution of compressive and tensile behaviors and associated mechanical properties of FR-CPB under various curing temperatures from early to advanced ages. Thus, this study aims to investigate the time (7, 28, and 90 d)- and temperature (20°C, 35°C, and 45°C)-dependence of constitutive behavior and mechanical properties of FR-CPB. The obtained results show that pre- and post-failure behaviors of FR-CPB demonstrate strongly curing temperature-dependence from early to advanced ages. Moreover, the pseudo-hardening behavior is sensitive to curing temperature, especially at early ages. Furthermore, the mechanical properties including elastic modulus, material stiffness, strengths, brittleness, cohesion, and internal friction angle of FR-CPB show increasing trends with curing temperature as curing time elapses. Additionally, a predictive model is developed to capture the strong correlation between compressive and tensile strength of FR-CPB. The findings of this study will contribute to the successful implementation of FR-CPB technology.

关键词： cemented paste backfill     fiber reinforcement     constitutive behavior     temperature     tailings    

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Novel sensing techniques for full-scale testing of civil structures

Kaoshan DAI, Zhenhua HUANG

《结构与土木工程前沿（英文）》 2012年 第6卷 第3期   页码 240-256 doi: 10.1007/s11709-012-0172-8

摘要： Performing full-scale structural testing is an important methodology for researchers and engineers in the civil engineering industry. Full scale testing helps the researchers understand civil infrastructures’ loading scenarios, behaviors, and health conditions. It helps the engineers verify, polish, and simplify the structural design and analysis theories. To conduct a full-scale structural testing, sensors are used for data acquisitions. To help structural researchers and engineers get familiar with sensing technologies and select the most effective sensors, this study reviewed and categorized new sensing techniques for full-scale structural testing applications. The researchers of this study categorized sensors used for civil-infrastructure testing into traditional contact sensors and remote sensors based upon their application methodologies, and into cabled sensors and wireless sensors based upon their data communication strategies. The detailed descriptions of wireless sensors and remote sensing techniques and their on-site full-scale applications are presented.

关键词： sensing technique     full-scale testing     wireless sensor     remote sensing     LiDAR     laser vibrometer    

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Catalytic hydrogenation of insoluble organic matter of CS/Acetone from coal over mesoporous HZSM-5 supported

《化学科学与工程前沿（英文）》 2022年 第16卷 第10期   页码 1505-1513 doi: 10.1007/s11705-022-2164-0

摘要： Four supported catalysts, nickel and ruthenium on a HZSM-5 support, were prepared by equal volume impregnation and in-situ decomposition of carbonyl nickel. The properties of catalysts were investigated by catalytic hydro-conversion of 2,2′-dinaphthyl ether as the model compound and extraction residue of Naomaohu lignite as the sample under an initial H2 pressure of 5 MPa and temperature at 150 °C. According to the catalytic hydro-conversion results of the model compound, Ni−Ru/HZSM-5 exhibited the best catalytic performance. It not only activated H2 into H···H, but also further heterolytically split H···H into immobile H‒ attached on the acidic centers of Ni−Ru/HZSM-5 and relatively mobile H+. Catalytic hydro-conversion of the extraction residue from Naomaohu lignite was further examined over the optimized catalyst, Ni−Ru/HZSM-5. Detailed molecular compositions of products from the extraction residue with and without hydrogenation were characterized by Fourier transform infrared spectroscopy and gas chromatography/mass spectrometry. The analytical results showed that the oxygen-containing functional groups in products of hydrogenated extraction residue were obviously reduced after the catalytic treatment. The relative content of oxygenates in the product with catalytic treatment was 18.57% lower than that in the product without catalytic treatment.

关键词： HZSM-5     Ni-based catalyst     catalytic hydrogenation     coal     model compound    

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标题 作者 时间 类型 操作

Gradient-based compressive image fusion

Yang CHEN,Zheng QIN

期刊论文

Design of an enhanced visual odometry by building and matching compressive panoramic landmarks online

Wei LU,Zhi-yu XIANG,Ji-lin LIU

期刊论文

Asymmetric transfer hydrogenation of prochiral ketone catalyzed over Fe-CS/SBA-15 catalyst

XUE Ping, WU Tao

期刊论文

预腐蚀后拉伸超载对LC4CS铝合金疲劳性能的影响

蒋荟,杨晓华

期刊论文

The ITZ microstructure, thickness, porosity and its relation with compressive and flexural strength of

期刊论文

Sediment environmental capacity of 137Cs in Daya Bay

ZHANG Junli, CHEN Jiajun, XU Jialin, LI Yuanxin, HUANG Naiming

期刊论文

Analytical algorithms of compressive bending capacity of bolted circumferential joint in metro shield

期刊论文

Optimizing the compressive strength of concrete containing micro-silica, nano-silica, and polypropylene

Fatemeh ZAHIRI, Hamid ESKANDARI-NADDAF

期刊论文

基于质量感知的水下图像自适应压缩方法

Ya-qiong CAI, Hai-xia ZOU, Fei YUAN

期刊论文

基于Wilkinson矩阵提升稀疏自适应匹配追踪重构效率

Rasha SHOITAN, Zaki NOSSAIR, I. I. IBRAHIM, Ahmed TOBAL

期刊论文

All-inorganic TiO/CsAgBiBr composite as highly efficient photocatalyst under visible light irradiation

期刊论文

evaluation of heavy metal contamination of sediment in Lake Dianchi by using modified AHP method and Cs

ZHANG Yan, GAO Xiang, ZHONG Zhenyu, PENG Buzhuo, DENG Xihai

期刊论文

Time- and temperature-dependence of compressive and tensile behaviors of polypropylene fiber-reinforced

期刊论文

Novel sensing techniques for full-scale testing of civil structures

Kaoshan DAI, Zhenhua HUANG

期刊论文

Catalytic hydrogenation of insoluble organic matter of CS/Acetone from coal over mesoporous HZSM-5 supported

期刊论文