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Chinese Physics B 2024年第4期33卷 640-648页

作者：陈登辉羊志付新宇秦申奥严岩王传奎李宗良邱帅 Shandong Key Laboratory of Medical Physics and image Processing&Shandong Provincial Engineering and Technical center of Light Manipulations School of Physics and ElectronicsShandong Normal UniversityJinan 250358China

Orientation-dependent transport properties induced by anisotropic molecules are enticing in single-molecule ***,using the first-principles method,we theoretically investigate spin transport properties and photoresponse characteristics in trimesic acid magnetic single-molecule junctions with different molecular adsorption orientations and electrode contact *** transport calculations indicate that a single-molecule switch and a significant enhancement of spin transport and photoresponse can be achieved when the molecular adsorption orientation changes from planar geometry to upright *** maximum spin polarization of current and photocurrent in upright molecular junctions exceeds 90%.Moreover,as the Ni tip electrode moves,the tunneling magnetoresistance of upright molecular junctions can be increased to 70%.The analysis of the spin-dependent PDOS elucidates that the spinterfaces between organic molecule and ferromagnetic electrodes are modulated by molecular adsorption orientation,where the molecule in upright molecular junctions yields higher spin *** theoretical work paves the way for designing spintronic devices and optoelectronic devices with anisotropic functionality base on anisotropic molecules.

关键词： molecular spintronics spin polarization tunneling magnetoresistance photocurrent single-molecule junctions

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Decoupled deep hough voting for point cloud registration

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Frontiers of Computer Science 2024年第2期18卷 147-155页

作者： Mingzhi YUAN Kexue FU Zhihao LI Manning WANG Digital Medical Research center School of Basic Medical SciencesFudan UniversityShanghai 200032China Shanghai Key Laboratory of Medical image Computing and Computer Assisted Intervention Shanghai 200032China

Estimating rigid transformation using noisy correspondences is critical to feature-based point cloud ***,a series of studies have attempted to combine traditional robust model fitting with deep *** them,DHVR proposed a hough voting-based method,achieving new state-of-the-art ***,we find voting on rotation and translation simultaneously hinders achieving better ***,we proposed a new hough voting-based method,which decouples rotation and translation ***,we first utilize hough voting and a neural network to estimate *** based on good initialization on rotation,we can easily obtain accurate rigid *** experiments on 3DMatch and 3DLoMatch datasets show that our method achieves comparable performances over the state-of-the-art *** further demonstrate the generalization of our method by experimenting on KITTI dataset.

关键词： point cloud registration robust model fitting deep learning hough voting

Spontaneous Recovery in Directed Dynamical Networks

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Engineering 2024年第6期37卷 208-214页

作者： Xueming Liu Xian Yan H.Eugene Stanley School of Artificial Intelligence and Automation&The MOE Engineering Research center of Autonomous Intelligent Unmanned Systems&the Key Laboratory of image Processing Huazhong University of Science and TechnologyWuhan 430074China center for Polymer Studies Department of PhysicsBoston UniversityBostonMA 02215USA

Complex networked systems,which range from biological systems in the natural world to infrastructure systems in the human-made world,can exhibit spontaneous recovery after a failure;for example,a brain may spontaneously return to normal after a seizure,and traffic flow can become smooth again after a *** studies on the spontaneous recovery of dynamical networks have been limited to undirected ***,most real-world networks are *** fill this gap,we build a model in which nodes may alternately fail and recover,and we develop a theoretical tool to analyze the recovery properties of directed dynamical *** find that the tool can accurately predict the final fraction of active nodes,and the prediction accuracy decreases as the fraction of bidirectional links in the network increases,which emphasizes the importance of directionality in network *** to different initial states,directed dynamical networks may show alternative stable states under the same control parameter,exhibiting hysteresis *** addition,for networks with finite sizes,the fraction of active nodes may jump back and forth between high and low states,mimicking repetitive failure-recovery *** findings could help clarify the system recovery mechanism and enable better design of networked systems with high resilience.

关键词： Network resilience Directed dynamical networks Spontaneous recovery

Learning group interaction for sports video understanding from a perspective of athlete

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Frontiers of Computer Science 2024年第4期18卷 175-188页

作者： Rui HE Zehua FU Qingjie LIU Yunhong WANG Xunxun CHEN Intelligent Recognition and image Processing(IRIP)Lab School of Computer Science and EngineeringBeihang UniversityBeijing 100191China Hangzhou Innovation Institute Behang UniversityHangzhou 310051China National Computer Network Emergency Response Technical Team/Coordination center of China(CNCERT or CNCERT/CC) Beijing 100029China

Learning activities interactions between small groups is a key step in understanding team sports *** research focusing on team sports videos can be strictly regarded from the perspective of the audience rather than the *** team sports videos such as volleyball and basketball videos,there are plenty of intra-team and inter-team *** this paper,a new task named Group Scene Graph Generation is introduced to better understand intra-team relations and inter-team relations in sports *** tackle this problem,a novel Hierarchical Relation Network is *** all players in a video are finely divided into two teams,the feature of the two teams’activities and interactions will be enhanced by Graph Convolutional Networks,which are finally recognized to generate Group Scene *** evaluation,built on Volleyball dataset with additional 9660 team activity labels,a Volleyball+dataset is proposed.A baseline is set for better comparison and our experimental results demonstrate the effectiveness of our ***,the idea of our method can be directly utilized in another video-based task,Group Activity *** show the priority of our method and display the link between the two ***,from the athlete’s view,we elaborately present an interpretation that shows how to utilize Group Scene Graph to analyze teams’activities and provide professional gaming suggestions.

关键词： group scene graph group activity recognition scene graph generation graph convolutional network sports video understanding

Impacts of artificial dams on terrestrial water storage changes and the Earth's elastic load response during 1950-2016: A case study of medium and large reservoirs in Chinese mainland

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Geodesy and Geodynamics 2024年第3期15卷 252-263页

作者： Linsong Wang Mingtao Zhu Yulong Zhong Jianwei Sun Zhenran Peng Hubei Subsurface Multiscale image Key Laboratory School of Geophysics and GeomaticsChina University of GeosciencesWuhan 430074China Three Gorges Research center for Geo-hazard Ministry of EducationChina University of GeosciencesWuhan 430074China School of Geography and Information Engineering China University of GeosciencesWuhan 430078China

The construction of dams for intercepting and storing water has altered surface water distributions, landsea water exchanges, and the load response of the solid Earth. The lack of accurate estimation of reservoir properties through the land surface and hydrological models can lead to water storage simulation and extraction errors. This impact is particularly evident in many artificial reservoirs in China. The study aims to comprehensively assess the spatiotemporal distribution and trends of water storage in medium and large reservoirs(MLRs) in Chinese mainland during 1950-2016, and to investigate the gravity,displacement, and strain effects induced by the reservoir mass concentration using the load elasticity theory. In addition, the impoundment contributions of MLRs to the relative sea level changes were assessed using a sea-level equation. The results show impoundment increases in the MLRs during1950-2016, particularly in the Yangtze River(Changjiang) and southern basins, causing significant elastic load effects in the surrounding areas of the reservoirs and increasing the relative sea level in China's offshore. However, long-term groundwater estimation trends are overestimated and underestimated in the Yangtze River and southwestern basins, respectively, due to the neglect of the MLRs impacts or the uncertainty of the hydrological model's output(e.g., soil moisture, etc.). The construction of MLRs may reduce the water mass input from land to the ocean, thus slowing global sea level rise. The results of the impact of human activities on the regional water cycle provide important references and data support for improving the integration of hydrological models, evaluating Earth's viscoelastic responses under longterm reservoir storage, enhancing in-situ and satellite geodetic measurements, and identifying the main factors driving sea level changes.

关键词： Man-made dams Terrestrial water storage Elastic load response Sea level changes Chinese mainland

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Low-Rank Optimal Transport for Robust Domain Adaptation

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IEEE/CAA Journal of Automatica Sinica 2024年第7期11卷 1667-1680页

作者： Bingrong Xu Jianhua Yin Cheng Lian Yixin Su Zhigang Zeng IEEE the School of Automation Wuhan University of TechnologyWuhan 430070China Intelligent Transportation Systems Research center Wuhan University of TechnologyWuhan 430063 Chongqing Research Institute Wuhan University of TechnologyChongqingChina the School of Artificial Intelligence and Automation Huazhong University of Science and TechnologyWuhan 430074 the Key Laboratory of image Processing and Intelligent Control of Education Ministry of China Wuhan 430074China

When encountering the distribution shift between the source(training) and target(test) domains, domain adaptation attempts to adjust the classifiers to be capable of dealing with different domains. Previous domain adaptation research has achieved a lot of success both in theory and practice under the assumption that all the examples in the source domain are welllabeled and of high quality. However, the methods consistently lose robustness in noisy settings where data from the source domain have corrupted labels or features which is common in reality. Therefore, robust domain adaptation has been introduced to deal with such problems. In this paper, we attempt to solve two interrelated problems with robust domain adaptation:distribution shift across domains and sample noises of the source domain. To disentangle these challenges, an optimal transport approach with low-rank constraints is applied to guide the domain adaptation model training process to avoid noisy information influence. For the domain shift problem, the optimal transport mechanism can learn the joint data representations between the source and target domains using a measurement of discrepancy and preserve the discriminative information. The rank constraint on the transport matrix can help recover the corrupted subspace structures and eliminate the noise to some extent when dealing with corrupted source data. The solution to this relaxed and regularized optimal transport framework is a convex optimization problem that can be solved using the Augmented Lagrange Multiplier method, whose convergence can be mathematically proved. The effectiveness of the proposed method is evaluated through extensive experiments on both synthetic and real-world datasets.

关键词： Domain adaptation low-rank constraint noise corruption optimal transport

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Effect of erythromycin on image quality and transit time of capsule endoscopy: A two-center study

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World Journal of Gastroenterology 2008年第16期14卷 2561-2565页

作者： Eva Niv Ido Bogner Olga Barkey Zamir Halpern Elisabeth Mahajna Roman Depsames Yael Kopelman Zvi Fireman Department of Gastroenterology Hillel Yaffe Medical Center Department of Gastroenterology Tel Aviv Sourasky Medical Center

AIM: To compare the effect of oral erythromycin vs no preparation with prokinetics on the transit time and the image quality of capsule endoscopy (CE) in evaluating small bowel (SB) pathology. METHODS: We conducted a retrospective, blinded (to the type of preparation) review of 100 CE studies, 50 with no preparation with prokinetics from one medical center (Group A) and 50 from another center with administration of a single dose of 200 mg oral erythromycin 1 h prior to CE (Group B). Gastric, SB and total transit times were calculated, the presence of bile in the duodenum was scored, as was cleanliness within the proximal, middle and distal intestine. RESULTS: The erythromycin group had a slightly shorter gastric transit time (21 min vs 28 min, with no statistical significance). SB transit time was similar for both groups (all P > 0.05). Total transit time was almost identical in both groups. The rate of incomplete examination was 16% for Group A and 10% for Group B (P = 0.37). Bile and cleanliness scores in different parts of the intestine were similar for the two groups (P > 0.05). CONCLUSION: Preparation for capsule endoscopy with erythromycin does not affect SB or total transit time. It tends to reduce gastric transit time, but it does not increase the cecum-reaching rate. Erythromycin does not adversely affect image quality. We consider the routine use of oral erythromycin preparation as being unjustified, although it might be considered in patients with known prolonged gastric emptying time.

关键词： Capsule endoscopy Gastric transit time Small bowel transit time Erythromycin image quality

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有向动态网络的自发恢复（英文）

Engineering 2024年第6期 208-214页

作者：刘雪明闫贤 H.Eugene Stanley School of Artificial Intelligence and Automation & The MOE Engineering Research center of Autonomous Intelligent Unmanned Systems & the Key Laboratory of image Processing Huazhong University of Science and Technology center for Polymer Studies Department of Physics Boston University

Complex networked systems, which range from biological systems in the natural world to infrastructure systems in the human-made world, can exhibit spontaneous recovery after a failure; for example, a brain may spontaneously return to normal after a seizure, and traffic flow can become smooth again after a jam. Previous studies on the spontaneous recovery of dynamical networks have been limited to undirected networks. However, most real-world networks are directed. To fill this gap, we build a model in which nodes may alternately fail and recover, and we develop a theoretical tool to analyze the recovery properties of directed dynamical networks. We find that the tool can accurately predict the final fraction of active nodes, and the prediction accuracy decreases as the fraction of bidirectional links in the network increases, which emphasizes the importance of directionality in network dynamics. Due to different initial states, directed dynamical networks may show alternative stable states under the same control parameter, exhibiting hysteresis behavior. In addition, for networks with finite sizes, the fraction of active nodes may jump back and forth between high and low states, mimicking repetitive failure-recovery processes. These findings could help clarify the system recovery mechanism and enable better design of networked systems with high resilience.

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Oscillating paramagnetic Meissner effect and Berezinskii-Kosterlitz-Thouless transition in underdoped Bi2Sr2CaCu2O8+δ

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National Science Review 2024年第5期11卷 142-152页

作者： Shiyuan Wang Yijun Yu Jinxiang Hao Keyi Liang Bingke Xiang Jinjiang Zhu Yishi Lin Yinping Pan Genda Gu Kenji Watanabe Takashi Taniguchi Yang Qi Yuanbo Zhang Yihua Wang State Key Laboratory of Surface Physics and Department of Physics Fudan University Condensed Matter Physics and Materials Science Department Brookhaven National Laboratory Research center for Functional Materials National Institute for Materials Science International center for Materials Nanoarchitectonics National Institute for Materials Science Shanghai Research center for Quantum Sciences

Superconducting phase transitions in two dimensions lie beyond the description of the Ginzburg-Landau symmetry-breaking paradigm for three-dimensional *** are Berezinskii-KosterlitzThouless（BKT） transitions of paired-electron condensate driven by the unbinding of topological excitations,*** recently discovered monolayers of layered high-transition-temperature（TC）cuprate superconductor Bi2Sr2CaCu2O8+δ（Bi2212） meant that this 2D superconductor promised to be ideal for the study of unconventional *** inhomogeneity posed challenges for distinguishing BKT physics from charge correlations in this ***,we utilize the phase sensitivity of scanning superconducting quantum interference device microscopy susceptometry to image the local magnetic response of underdoped Bi2212 from the monolayer to the bulk throughout its phase *** monolayer segregates into domains with independent phases at elevated temperatures below *** a single domain,we find that the susceptibility oscillates with flux between diamagnetism and paramagnetism in a Fraunhofer-like pattern up to *** finite modulation period,as well as the broadening of the peaks when approaching Tc from below,suggests well-defined vortices that are increasingly screened by the dissociation of vortex-antivortex plasma through a BKT *** the multilayers,the susceptibility oscillation differs in a small temperature regime below TC,consistent with a dimensional crossover led by interlayer *** as strong evidence for BKT transition in the bulk,we observe a sharp jump in phase stiffness and paramagnetism at small fields just below *** results unify the superconducting phase transitions from the monolayer to the bulk underdoped Bi2212,and can be collectively referred to as the BKT transition with interlayer coupling.

关键词： cuprate superconductor monolayer Berezinskii-Kosterlitz-Thouless transition scanning SQUID paramagnetic Meissner effect

Perioperative complication incidence and risk factors for retroperitoneal neuroblastoma in children:analysis of 571 patients

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World Journal of Pediatrics 2024年第3期20卷 250-258页

作者： Min He Jia-Bin Cai Xuan Wu Yin-Bing Tang Jin-Yan Wang Jun-Qin Mao Ji-Jun Chen Li-Feng Zhang Zhong-Hai Guan Jie-Ni Xiong Wan-Xin Peng Jin-Hu Wang Ting Tao Pediatric Cancer Research center National Clinical Research Center for Child HealthHangzhouChina Department of Surgical Oncology Children's HospitalZhejiang University School of MedicineHangzhouChina Cancer center Zhejiang UniversityNo.3333 Binsheng RodeHangzhouChina

Background Surgery plays an important role in the treatment of *** complications may impact the course of neuroblastoma *** date,comprehensive analyses of complications and risk factors have been *** Patients with retroperitoneal neuroblastoma undergoing tumor resection were retrospectively analyzed between 2014 and *** data collected included clinical characteristics,operative details,operative complications and postopera-tive *** factors for perioperative complications of retroperitoneal neuroblastoma were *** A total of 571 patients were enrolled in this *** complications were observed in 255(44.7%)*** leakage(28.4%),diarrhea(13.5%),and injury(vascular,nerve and organ;7.5%)were the most frequent *** were three operation-related deaths(0.53%):massive hemorrhage(n=1),biliary tract perforation(n=1)and intestinal necrosis(n=1).The presence of image-defined risk factors(IDRFs)[odds ratio(OR)=2.09,P<0.01],high stage of the International Neuroblastoma Risk Group staging system(INRGSS)(OR=0.454,P=0.04),retroperitoneal lymph node metastasis(OR=2.433,P=0.026),superior mesenteric artery encasement(OR=3.346,P=0.003),and inferior mesenteric artery encasement(OR=2.218,P=0.019)were identified as independent risk factors for perioperative *** Despite the high incidence of perioperative complications,the associated mortality rate was quite ***-perative complications of retroperitoneal neuroblastoma were associated with IDRFs,INRGSS,retroperitoneal lymph node metastasis and vascular *** with high-risk factors should receive more serious attention during surgery but should not discourage the determination to pursue total resection of neuroblastoma.

关键词： Complication Neuroblastoma Risk factors Surgery