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Comparison between radarsat-1.SAR different data modes for oil spill detection by a fractal box counting algorithm

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International Journal of Digital Earth 2009年第3期2卷 237-256页

作者： M.Marghany A.P.Cracknell M.Hashim natural Tropical {1. Information&Mapping Research Group(NATRIM Research Group) Faculty of Geoinformation Science and EngineeringUniversiti Teknologi Malaysia81310 UTMSkudaiJohore BahruMalaysia department of Remote Sensing Faculty of Geoinformation Science and EngineeringUniversiti Teknologi Malaysia81310 UTMSkudaiJohore BahruMalaysia

This work presents a modified formula for the fractal box counting *** method is based on the utilisation of the probability distribution formula in the fractal box *** purpose of this method is to use it for the discrimination of oil spill areas from the surrounding features,*** surface and look-alikes,using RADARSAT-1.SAR Wide beam mode(W1.,Standard beam mode(S2)and Standard beam mode(S1.data acquisition under different wind *** results show that the new formula is able to discriminate between oil spills and look-alike *** results also illustrate that the new fractal formula identifies well the deficiency of oil spills in pairs of S2 ***,there are no significant differences between fractal values of look-alikes,low wind zone,and current shear features in different beam modes for acquisition of RADARSAT-1.SAR *** W1.mode data,however,show an error standard deviation of 0.002,thus performing a better discrimination of oil spills than the S1.and S2 mode data.

关键词： RADARSAT-1.SAR oil spill look-alike low wind zone fractal dimension

Single cell analysis unveils B cell-dominated immune subtypes in HNSCC for enhanced prognostic and therapeutic stratification

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International Journal of Oral Science 2024年第3期16卷 448-459页

作者： Kang Li Caihua Zhang Ruoxing Zhou Maosheng Cheng Rongsong Ling Gan Xiong Jieyi Ma Yan Zhu Shuang Chen Jie Chen Demeng Chen Liang Peng State Key Laboratory of Oncology in South China Department of Oral and Maxillofacial SurgeryInstitute of Precision MedicineCenter for Translational MedicineThe First Affiliated Hospital of Sun Yat-sen UniversityGuangzhouChina Institute for Advanced Study Shenzhen UniversityShenzhenChina Hospital of Stomatology Guangdong Provincial Key Laboratory of StomatologyGuanghua School of StomatologySun Yat-Sen UniversityGuangzhouChina Senior department of Oncology The Fifth Medical Center of PLA General HospitalBeijingChina

Head and neck squamous cell carcinoma(HNSCC)is characterized by high recurrence or distant metastases rate and the prognosis is *** is mounting evidence that tumor-infiltrating B cells(TIL-Bs)have a crucial,synergistic role in tumor ***,little is known about the role TIL-Bs play in immune microenvironment and the way TIL-Bs affect the outcome of immune checkpoint *** single-cell RNA sequencing(scRNA-seq)data from the Gene Expression Omnibus(GEO)database,the study identified distinct gene expression patterns in *** samples were categorized into TIL-Bs inhibition and TIL-Bs activation groups using unsupervised *** classification was further validated with TCGA HNSCC data,correlating with patient prognosis,immune cell infiltration,and response to *** found that the B cells activation group exhibited a better prognosis,higher immune cell infiltration,and distinct immune checkpoint levels,including elevated PD-L1.A prognostic model was also developed and validated,highlighting four genes as potential biomarkers for predicting survival outcomes in HNSCC ***,this study provides a foundational approach for B cells-based tumor classification in HNSCC,offering insights into targeted treatment and immunotherapy strategies.

关键词： prognosis elevated offering

Temporal study of GRS 1.1.+1.5 with rms-flux relation:The importance of magnetic activities in the corona

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Science China(Physics,Mechanics & Astronomy) 2010年第S1期53卷 120-124页

作者： HAN Dong1.ZHANG ShuangNan2 & SONG LiMing2 1.department of Engineering Physics & Center for Astrophysics,Tsinghua University,Beijing 1.0084,China 2 Key Laboratory of Particle Astrophysics,Institute of High Energy Physics,Chinese Academy of Sciences,Beijing 1.0049,China 1. department of Engineering Physics & Center for Astrophysics Tsinghua University Beijing 100084 China 2. Key Laboratory of Particle Astrophysics Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China

The rms-flux relations for some observations of GRS 1.1.+1.5 are *** rms-flux relations of the light curves in only one state,state C or state A,can be described by the simple non-linear model provided Zhang;we thus interpret that such a linear relation reflects the relative importance of magnetic instability for X-ray emission in the corona of the system,compared to the thermal viscous instability for the X-ray emission in the accretion *** rms-flux relations for state B are very scattered,possibly because of the dominance of thermal viscous instability for the X-ray emission in the accretion *** complex rms-flux relations for the observations of transitions between two or three states are caused by the combination of the different rms-flux relations of these *** underlying physical processes are the combination of magnetic topology in the corona and thermal viscous instability in the accretion disk.

关键词： rms-flux relation data analysis GRS 1.1.+1.5 magnetic instability

Multi-population particle swarm optimization algorithm for automatic design of steel frames

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Frontiers of Structural and Civil Engineering 2024年第1期18卷 89-103页

作者： Wenchen SHAN Jiepeng LIU Yao DING Y.Frank CHEN Junwen ZHOU Institute of Smart City and Intelligent Transportation Southwest Jiaotong UniversityChengdu 610000China School of Civil Engineering Chongqing UniversityChongqing 400045China department of Civil Engineering the Pennsylvania State UniversityMiddletownPA 17057USA

Steel structures are widely used;however,their traditional design method is a trial-and-error procedure which is neither efficient nor cost ***,a multi-population particle swarm optimization(MPPSO)algorithm is developed to optimize the weight of steel frames according to standard design *** are made to improve the algorithm performances including the constraint-based strategy,piecewise mean learning strategy and multi-population cooperative *** proposed method is tested against the representative frame taken from American standards and against other steel frames matching Chinese design *** related parameter influences on optimization results are *** the representative frame,MPPSO can achieve greater efficiency through reduction of the number of analyses by more than 65% and can obtain frame with the weight for at least 2.4%lighter.A similar trend can also be observed in cases subjected to Chinese design *** addition,a migration interval of 1.and the number of populations as 5 are recommended to obtain better MPPSO *** purpose of the study is to propose a method with high efficiency and robustness that is not confined to structural scales and design *** aims to provide a reference for automatic structural optimization design problems even with dimensional *** proposed method can be easily generalized to the optimization problem of other structural systems.

关键词： steel frame multi-population particle swarm optimization automatic structural optimization design

MAUN:Memory-Augmented Deep Unfolding Network for Hyperspectral Image Reconstruction

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IEEE/CAA Journal of Automatica Sinica 2024年第5期11卷 1139-1150页

作者： Qian Hu Jiayi Ma Yuan Gao Junjun Jiang Yixuan Yuan Electronic Information School Wuhan UniversityWuhan 430072China School of Computer Science and Technology Harbin Institute of TechnologyHarbin 150001China department of Electronic Engineering Chinese University of Hong KongHong Kong 999077China

Spectral compressive imaging has emerged as a powerful technique to collect the 3D spectral information as 2D *** algorithm for restoring the original 3D hyperspectral images(HSIs)from compressive measurements is pivotal in the imaging *** approaches painstakingly designed networks to directly map compressive measurements to HSIs,resulting in the lack of interpretability without exploiting the imaging *** some recent works have introduced the deep unfolding framework for explainable reconstruction,the performance of these methods is still limited by the weak information transmission between iterative *** this paper,we propose a Memory-Augmented deep Unfolding Network,termed MAUN,for explainable and accurate HSI ***,MAUN implements a novel CNN scheme to facilitate a better extrapolation step of the fast iterative shrinkage-thresholding algorithm,introducing an extra momentum incorporation step for each iteration to alleviate the information ***,to exploit the high correlation of intermediate images from neighboring iterations,we customize a cross-stage transformer(CSFormer)as the deep denoiser to simultaneously capture self-similarity from both in-stage and cross-stage features,which is the first attempt to model the long-distance dependencies between iteration *** experiments demonstrate that the proposed MAUN is superior to other state-of-the-art methods both visually and *** code is publicly available at https://***/HuQ1.n/MAUN.

关键词： Deep folding iteration

In-plane attenuation zone and its optimization in a plate with periodic holes

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Chinese Journal of Acoustics 2019年第1期38卷 85-98页

作者： LIU Xiongwei HUANG Jiankun HU Yucun LI Yaguang LIU Wen department of Civil Engineering School of Soil and Water ConservationBeijing Forestry University

It is difficult to design a plate with wide attenuation zones in low frequency region based on Bragg scattering mechanism. A plate with periodic rhombic holes is optimized and designed. Based on the finite element method under periodic boundary conditions, the in-plane dispersion curves of periodically perforated plate are calculated via COMSOL. The frequency responses of periodically perforated plate axe investigated via ANSYS simulation. The plates with periodic holes are suspended and dynamically tested under sinusoidal excitations. The results show that a periodically perforated plate with rhombus holes has wider attenuation zones than plates with circular and hexagonal holes. Material properties have a great influence on attenuation zones: nitrile-butadiene rubber and silicon rubber can easily obtain low-frequency zones, while increasing porosity creates lower and wider zones. The width of attenuation zone increases as the horizontal angle of the rhombus holes increases. An analysis of the attenuation zones* generation mechanism shows that the plate with periodic holes exhibits characteristics of Bragg scattering and local resonant phononic crystal, indicating an inherent relationship between two types of mechanisms. The optimized plate has a complete attenuation zone ranging from 5281.76-8824.30 Hz. The vibrations are significantly reduced when the number of periods is no less than two. The attenuation range obtained via the numerical method is generally consistent with the experiment. The research sheds light on the noise insulation plate and has the potential to improve the sound environment in various applications due to its simple manufacturing.

关键词： In-plane attenuation zone plate with periodic holes COMSOL

Anomalous{1012}tensile twinning and subsequent detwinning in a friction stir processed carbon fiber-reinforced Mg composite

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Journal of Magnesium and Alloys 2024年第4期12卷 1511-1517页

作者： Wei Zhao Zhihao Jiang Xiang Wu Yujing Liu Haokun Yang Jun Wang Qi Liu Xiaochun Liu Institute of Metals College of Materials Science and EngineeringChangsha University of Science&TechnologyChangsha 410114China department of Mechanical Engineering City University of Hong KongHong KongChina Smart manufacturing division Hong Kong Productivity CouncilHong Kong SAR 999077China Institute for Frontier Materials Deakin UniversityGeelongVIC 3216Australia department of Industrial and Systems Engineering The Hong Kong Polytechnic UniversityHong KongChina

*** text Owing to their low density and high specific strength,magnesium alloys and magnesium-based composites have great potential as structure metal materials in applications where lightweight matters[1–4].Deformation twins[5],especially the{1012}tension twins(also called tensile or extension twins)with a low critical resolved shear stress(CRSS)[6],are commonly observed in Mg *** can provide the much-needed deformation along the c-axis in their hcp structure resulting from the very few easily activated slip systems in this crystal structure[7].The tensile twinning activation usually follows the macroscopic Schmid factor law[2],i.e.,the twin variant with the highest Schmid factor occurs,and it only appears when its Schmid factor is positive.

关键词： friction deformation magnesium

Quantitative division of succession and spatial patterns among different stand developmental stages in Changbai Mountains

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Journal of Mountain Science 2019年第9期16卷 2063-2078页

作者： GONG Zhi-wen KANG Xin-gang GU Li College of Economics and Management Research Center of Resource Economics and Environment Management Northwest A8J7 University Yangling 712100 China College of forestry Northwest A&F University Yang ling 712100 China College of forestry Beijing Forestry University Beijing 100083 China

Broadleaf-Korean pine forests exhibit high species richness and distinctive species composition, which are currently becoming more dominant among natural forests in Changbai Mountains of northeastern China. Understanding the ecological process of restored vegetation is quite important for ecosystem reconstruction. Distinguishing stand development stages and analyzing the dynamic spatial patterns could provide insights into significant community coexistence mechanisms. In the present study, eight permanent study areas were established according to the substituting space for time method in Changbai Mountains of north-eastern China. The optimal division method was used to quantify the successional series into different stand development stages, and the point pattern analysis method(L(r) function) was used to analyse the dynamic changes in spatial patterns and interspecific associations. Our results suggested that:(1. The stand development process was divided into five stages: the first three stages were poplar-birch secondary forests in different stages of recovery, the fourth stage was thespruce-fir mixed forest, and the last stage was the primary broadleaf-Korean pine forest;(2) The spatial pattern showed an aggregated distribution at a small scale and changed to a random distribution as the scale increased in poplar-birch secondary forests, but the spatial pattern appeared to be randomly distributed in spruce-fir mixed forest and broadleafKorean pine forest;(3) The interspecific associations between pioneer species and climax species changed from negative to positive among the different stand stages, and environmental {1. were shared among these species. Interspecific differences in shade tolerance among the tree species were key determinants of forest dynamics and structure. Our study is vital to the understanding of the forest development;thus, the spatial change features should receive greater attention when forest management is being planned and restoratio

关键词： Dynamic spatial patterns Interspecific association Optimal division method Stand developmental stages Space for time substitution

Hydrocarbon Generation Potential and Organic Matter Enrichment Mechanism of the Cambrian Marine Shale in the Tadong Low Uplift, Tarim Basin

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Acta Geologica Sinica(English Edition) 2024年第5期 1301-1321页

作者： MIAO Huan WANG Yanbin JIANG Zhenxue ZHAO Shihu SHANG Peng GONG Xun TAO Chuanqi ZHANG Yu State Key Laboratory of petroleum resources and Engineering China University of Petroleum Unconventional Unconventional Petroleum Research Institute Research Institute China University of Petroleum College of Geoscience and Surveying Engineering China University of Mining and Technology Petroleum Exploration and Production Research Institute SINOPEC Second Gas Production Plant PetroChina Changqing Oilfield Company School of Earth and Space Sciences Peking University School of Civil Engineering Liaoning Petrochemical University

Cambrian shales in China and elsewhere contain abundant oil and gas resources. However, due to its deep burial and limited outcrop, there has been relatively little research conducted on it. The Cambrian shale of the Tadong low uplift in the Tarim Basin of western China, specifically the Xidashan–Xishanbulake Formation（Fm.） and overlying Moheershan Fm. provide a case study through the use of organic petrology, mineralogy, organic and elemental geochemistry, with the aim of analyzing and exploring the hydrocarbon generation potential（PG） and organic matter（OM） enrichment mechanisms within these shale formations. The results indicate that:（1. the Cambrian shale of the Tadong low uplift exhibits relatively dispersed OM that consists of vitrinite-like macerals and solid bitumen. These formations have a higher content of quartz and are primarily composed of silica-based lithology;（2） shale samples from the Xidashan–Xishanbulake and Moheershan formations demonstrate high total organic carbon（TOC） and low pyrolytic hydrocarbon content（S2） content. The OM is predominantly type Ⅰ and type Ⅱ kerogens, indicating a high level of maturation in the wet gas period. These shales have undergone extensive hydrocarbon generation, showing characteristics of relatively poor PG;（3） the sedimentary environments of the Xidashan–Xishanbulake and Moheershan formations in the Tadong low uplift are similar. They were deposited in warm and humid climatic conditions, in oxygen-deficient environments, with stable terrigenous inputs, high paleoproductivity, high paleosalinity, weak water-holding capacity, and no significant hydrothermal activity; and（4） the relationship between TOC and the paleoproductivity parameter（P/Ti） is most significant in the Lower Cambrian Xidashan–Xishanbulake Fm., whereas correlation with other indicators is not evident. This suggests a productivity-driven OM enrichment model, where input of landderived material was relatively small during the Middle Cambrian, and the a

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