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Study on Wave Characteristics from the South Atlantic Ocean to the Gulf of Guinea Based on Short-Term Numerical Simulation in Winter Season

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China Ocean Engineering 2023年第2期37卷 312-322页

作者： XU Fu-min ZHENG Jin-hai YA han-zheng xing tian Key Laboratory of Ministry of Education for Coastal Disaster and Protection Hohai UniversityNanjing 210098China College of Harbor Coastal and Offshore EngineeringHohai UniversityNanjing 210098China

Waves play a major role in the ocean phenomena in the Gulf of Guinea(GoG). In order to reveal the spatial-temporal distribution characteristics and the propagation mechanism of waves from the South Atlantic Ocean to the GoG, 4typical points located in mid-latitude of South Atlantic(14°30′W, 30°0′S), south of the GoG(10°30′W, 15°0′S), offshore of the GoG(0°0′, 0°0′) and near shore of the GoG(6°4′58.8″W, 4°3′36″S) are selected, and waves from Atlantic Ocean to GoG are simulated by using a two-layer-nesting wave numerical model SWAN(Simulating Waves Nearshore). The results show that the hybrid waves(waves hereafter) and the swells have strong relationship with local wind in Roaring Forties and at mid-latitude of South Atlantic Ocean, while there is no obvious correlation between waves and local winds in the GoG. Swells are generated in the South Atlantic Ocean and propagate into the GoG. 2D wave spectra at the four selected typical points are simulated. The spectral pattern and wave component structure indicate that the wave system in GoG is dominated by the S-SW swells generated from Roaring Forties and mid-latitude of South Atlantic, whether it is at maximum(2.2-2.8 m), medium(1.8-2.2 m) or minimum(1.2 m) significant wave height in the GoG during simulation period.

关键词： Gulf of Guinea wave characteristics 2D wave spectra swell roaring forties

基于SBAS-InSAR和光学遥感的天津市北部山区潜在滑坡识别研究

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灾害学 2025年第1期40卷 30-35页

作者：王勇邢振涛李锁闫勇司甜天津城建大学地质与测绘学院天津300384 天津市地质工程勘测设计院有限公司天津300191

以天津市北部山区为研究对象,开展潜在滑坡识别研究,利用差分干涉测量短基线集时序分析技术(SBAS-InSAR)处理2018-01—2022-08的56景Sentinel-1A数据,并结合2018—2022年的Landsat8光学遥感影像,分析形变与光学遥感影像特征以及NDVI,筛... 详细信息

以天津市北部山区为研究对象,开展潜在滑坡识别研究,利用差分干涉测量短基线集时序分析技术(SBAS-InSAR)处理2018-01—2022-08的56景Sentinel-1A数据,并结合2018—2022年的Landsat8光学遥感影像,分析形变与光学遥感影像特征以及NDVI,筛选出潜在滑坡区域。研究结果表明:基于SBAS-InSAR技术识别的天津北部山区的形变较大区域有20处,使用光学遥感影像结合各发育环境要素进行处理确定的区域有19处,其中5处经两种技术确认为滑坡隐患,通过对该5处沉降信息进行识别分析,该5处区域最大年形变速率可达-12 mm/a,需要进行重点监测预警,使用两种技术结合对滑坡隐患区域进行识别可以有效地提高识别准确度,为天津北部山区灾害监测提供新的方式。

关键词：潜在滑坡 SBAS-InSAR 光学遥感影像天津市北部山区

Learning a discriminative high-fidelity dictionary for single channel source separation

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Journal of Systems Engineering and Electronics 2021年第5期32卷 1097-1110页

作者： tian Yuanrong WANG xing School of Electronic Countermeasure National University of Defense TechnologyHefei 230037China Institute of Aeronautics Engineering Air Force Engineering UniversityXi’an 710038China

Sparse-representation-based single-channel source separation,which aims to recover each source’s signal using its corresponding sub-dictionary,has attracted many scholars’*** basic premise of this model is that each sub-dictionary possesses discriminative information about its corresponding source,and this information can be used to recover almost every sample from that ***,in a more general sense,the samples from a source are composed not only of discriminative information but also common information shared with other *** paper proposes learning a discriminative high-fidelity dictionary to improve the separation *** innovations are ***,an extra sub-dictionary was combined into a conventional union dictionary to ensure that the source-specific sub-dictionaries can capture only the purely discriminative information for their corresponding sources because the common information is collected in the additional ***,a task-driven learning algorithm is designed to optimize the new union dictionary and a set of weights that indicate how much of the common information should be allocated to each ***,a source separation scheme based on the learned dictionary is *** results on a human speech dataset yield evidence that our algorithm can achieve better separation performance than either state-of-the-art or traditional algorithms.

关键词： single channel source separation sparse representation dictionary learning discrimination high-fidelity

Survey on person re-identification based on deep learning

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CAAI Transactions on Intelligence Technology 2018年第4期3卷 219-227页

作者： Kejun Wang Haolin Wang Meichen Liu Xianglei xing tian han College of Automation Harbin Engineering UniversityNo.145 Nantong StreetNangang DistrictHarbinPeople’s Republic of China Department of Statistics University of CaliforniaLos AngelesLos AngelesCA 90095USA

Person re-identification(Re-ID)is a fundamental subject in the field of the computer vision *** traditional methods of person Re-ID have difficulty in solving the problems of person illumination,occlusion and attitude change under complex ***,the introduction of deep learning opens a new way of person Re-ID research and becomes a hot spot in this *** study reviews the traditional methods of person Re-ID,then the authors focus on the related papers about different person Re-ID frameworks on the basis of deep learning,and discusses their advantages and ***,they propose the direction of further research,especially the prospect of person Re-ID methods based on deep learning.

关键词： Person re-identification

Cloud detection from visual band of satellite image based on variance of fractal dimension

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Journal of Systems Engineering and Electronics 2019年第3期30卷 485-491页

作者： tian Pingfang GUANG Qiang LIU xing School of Computer Science and Technology Wuhan University of Science and Technology Wuhan 430065 China Key Laboratory of Intelligent Information Processing and Real-Time Industrial System in Hubei Province Wuhan 430065 China Institute of Big Data Science and Engineering Wuhan University of Science and Technology Wuhan 430065 China Key Laboratory of Rich-Media Knowledge Organization and Service of Digital Publishing Content National Press and Publication Administration Beijing 100038 China

Cover ratio of cloud is a very important factor which affects the quality of a satellite image, therefore cloud detection from satellite images is a necessary step in assessing the image quality. The study on cloud detection from the visual band of a satellite image is developed. Firstly, we consider the differences between the cloud and ground including high grey level, good continuity of grey level, area of cloud region, and the variance of local fractal dimension (VLFD) of the cloud region. A single cloud region detection method is proposed. Secondly, by introducing a reference satellite image and by comparing the variance in the dimensions corresponding to the reference and the tested images, a method that detects multiple cloud regions and determines whether or not the cloud exists in an image is described. By using several Ikonos images, the performance of the proposed method is demonstrated.

关键词： cloud detection visual image satellite image variance of local fractal dimension (VLFD)

Involvement of Opioid Peptides in the Analgesic Effect of Spinal Cord Stimulation in a Rat Model of Neuropathic Pain

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Neuroscience Bulletin 2022年第4期38卷 403-416页

作者： Fu-Jun Zhai Song-Ping han tian-Jia Song Ran Huo xing-Yu Lan Rong Zhang Ji-Sheng han Neuroscience Research Institute Peking UniversityBeijing 100191China Department of Neurobiology School of Basic Medical SciencesPeking UniversityBeijing 100191China Key Laboratory for Neuroscience Ministry of EducationNational Health CommissionPeking UniversityBeijing 100191China Wuxi hanS Health Medical Technology Co. Ltd.Wuxi 214122China Department of Integration of Chinese and Western Medicine School of Basic Medical SciencesPeking UniversityBeijing 100191China

Spinal cord stimulation(SCS)-induced analgesia was characterized,and its underlying mechanisms were examined in a spared nerve injury model of neuropathic pain in *** analgesic effect of SCS with moderate mechanical hypersensitivity was increased with increasing stimulation intensity between the 20%and 80%motor *** frequencies(2,15,50,100,10000 Hz,and 2/100 Hz dense-dispersed)of SCS were similarly ***-induced analgesia was maintained without tolerance within 24 h of continuous *** at 2 Hz significantly increased methionine enkephalin content in the cerebrospinal *** analgesic effect of 2 Hz was abolished byμorκopioid receptor *** effect of 100 Hz was prevented by aκantagonist,and that of 10 kHz was blocked by any of theμ,δ,orκreceptor antagonists,suggesting that the analgesic effect of SCS at different frequencies is mediated by different endorphins and opioid receptors.

关键词： SCS Analgesia Opioid receptors Methionine-Enkephalin Dynorphin Endorphins

Protein induced by vitamin K absence or antagonist-Ⅱ versus alpha-fetoprotein in the diagnosis of hepatocellular carcinoma: A systematic review with meta-analysis

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Hepatobiliary & Pancreatic Diseases International 2018年第6期17卷 487-495页

作者： Hao xing Yi-Jie Zheng Jun han han Zhang Zhen-Li Li Wan-Yee Lau Feng Shen tian Yang Department of Hepatic Surgery Eastern Hepatobiliary Surgery Hospital Naval Medical University Medical Scientific Affairs Abbott Diagnostics Faculty of Medicine The Chinese University of Hong Kong

Background: As a promising biomarker of hepatocellular carcinoma(HCC), protein induced by vitamin K absence or antagonist-Ⅱ(PIVKA-Ⅱ) has been studied extensively. However, its diagnostic capability varies across HCC studies. This study aimed to compare the performance of PIVKA-Ⅱ with alpha-fetoprotein(AFP) in the diagnosis of HCC. Data sources: A systematic literature search was conducted to identify the studies from MEDLINE, Embase and Cochrane Library Databases, which were published up to December 20, 2017 to compare the diagnostic capability of PIVKA-Ⅱ and AFP for HCC. The data were pooled using random effects model. Pooled sensitivity and specificity were calculated. Summary receiver operating characteristic curve(ROC) was employed to evaluate the diagnostic accuracy of each marker. Results: Thirty-one studies were included. The pooled sensitivity(95% CI) of PIVKA-Ⅱ and AFP was 0.66(0.65–0.68) and 0.66(0.65–0.67), respectively in diagnosis of HCC; and the corresponding pooled specificity(95% CI) was 0.89(0.88–0.90) and 0.84(0.83–0.85), respectively. The area under the ROC curve(AUC) of PIVKA-Ⅱ and AFP was 0.856(0.817–0.895) and 0.770(0.728–0.811), respectively. Subgroup analysis showed that PIVKA-Ⅱ was superior to AFP in terms of the AUC for both small HCC( han AFP in terms of the accuracy for diagnosing HCC, regardless of tumor size, patient ethnic group, or HCC etiology.

关键词： Hepatocellular carcinoma Meta-analyses Protein induced by vitamin K absence or antagonist-Ⅱ Alpha-fetoprotein

A Cognitive Memory-Augmented Network for Visual Anomaly Detection

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IEEE/CAA Journal of Automatica Sinica 2021年第7期8卷 1296-1307页

作者： tian Wang xing Xu Fumin Shen Yang Yang the Center for Future Multimedia and School of Computer Science and Engineering University of Electronic Science and Technology of China(UESTC)Chengdu 611731China the Center for Future Multimedia and School of Computer Science and Engineering University of Electronic Science and Technology of ChinaChengdu 611731 the Institute of Electronic and Information Engineering of UESTC in Guangdong Dongguan 523808China

With the rapid development of automated visual analysis,visual analysis systems have become a popular research topic in the field of computer vision and automated *** analysis systems can assist humans to detect anomalous events(e.g.,fighting,walking alone on the grass,etc).In general,the existing methods for visual anomaly detection are usually based on an autoencoder architecture,i.e.,reconstructing the current frame or predicting the future ***,the reconstruction error is adopted as the evaluation metric to identify whether an input is abnormal or *** flaws of the existing methods are that abnormal samples can also be reconstructed *** this paper,inspired by the human memory ability,we propose a novel deep neural network(DNN)based model termed cognitive memory-augmented network(CMAN)for the visual anomaly detection *** proposed CMAN model assumes that the visual analysis system imitates humans to remember normal samples and then distinguishes abnormal events from the collected ***,in the proposed CMAN model,we introduce a memory module that is able to simulate the memory capacity of humans and a density estimation network that can learn the data *** reconstruction errors and the novelty scores are used to distinguish abnormal events from *** addition,we develop a two-step scheme to train the proposed model so that the proposed memory module and the density estimation network can cooperate to improve *** experiments evaluated on various popular benchmarks show the superiority and effectiveness of the proposed CMAN model for visual anomaly detection comparing with the state-of-the-arts *** implementation code of our CMAN method can be accessed at https://***/CMANcode/CMAN_pytorch.

关键词： Cognitive computing density estimation memory visual analysis systems visual anomaly detection.

Topologically protected entanglement switching around exceptional points

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Light(Science & Applications) 2024年第8期13卷 1631-1644页

作者： Zan Tang tian Chen xing Tang Xiangdong Zhang Key Laboratory of Advanced Optoelectronic Quantum Architecture and Measurements of Ministry of Education Beijing Key Laboratory of Nanophotonics&Ultrafine Optoelectronic SystemsSchool of PhysicsBeijing Institute of Technology100081 BeijingChina

The robust operation of quantum entanglement states is crucial for applications in quantum information,computing,and communications^(1–3).However,it has always been a great challenge to complete such a task because of decoherence and ***,we propose theoretically and demonstrate experimentally an effective scheme to realize robust operation of quantum entanglement states by designing quadruple degeneracy exceptional *** encircling the exceptional points on two overlapping Riemann energy surfaces,we have realized a chiral switch for entangled states with high *** to the topological protection conferred by the Riemann surface structure,this switching of chirality exhibits strong robustness against perturbations in the encircling ***,we have experimentally validated such a scheme on a quantum walk *** work opens up a new way for the application of non-Hermitian physics in the field of quantum information.

关键词： exceptional quantum Riemann