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Low-rank matrix recovery with total generalized variation for defending adversarial examples

中国土木工程学会第九届土力学及岩土工程学术会议

作者： c.w.w.ng c.F.cHIU The Hong Kong University of Science and Technology Clear Water Bay HKSAR China

Failures of initially loose unsaturated man- made (or fill) slopes due to rainfall infiltration are not uncommon in many parts of the world. Some of these failures are reported as caused by static liquefaction. However, the behaviour and the transformation from initially loose unsaturated to saturated states of soils, well - graded decomposed material in particular, are not fully understood and correctly modelled. The word "loose" refers to the state of soil lies on the wet (or loose) side of the critical state (cS). In this paper, the stress -strain relationship, shear and volumetric behaviour of two common fill materials (i. e. , coarse grained decomposed granite (DG) and fine- grained decomposed volcanic (DV)) in Hong Kong are reviewed. Based on the results of three series of triaxial tests on both saturated and unsaturated IDG and DV, a new state - dependent elasto- plastic constitutive model for unsaturated soils is formulated and presented. Saturated soil behaviour is regarded as a special case of unsaturated soil phenomenon at zero suction. The model, which is developed under the extended critical state framework, uses two independent stress state variables including the net normal stress and matric suction. The influence of internal state (stress level and density) on dilatancy is incorporated by using a state - dependent dilatancy formulation. with this new model, numerical simuktions of the three series of triaxial tests are carried out on both saturated and unsaturated DG and DV and compared with experimental observations. The computed results show that the stress - strain and volumetric - axial strain relationships of the saturated and unsaturated DG and DV at the loose and dense states can be captured properly by the model using a single set of parameters. Moreover, the model is able to simulate some key aspects of material behaviour such as a sudden increase in axial strain and volumetric strain as suction is reduced under a constant deviator stress, w

关键词： constitutive modeling loose fill state dependent dilatancy unsaturated

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Frontiers of Information Technology & Electronic Engineering 2024年第3期25卷 432-445页

作者： wen LI Hengyou wAng Lianzhi HUO Qiang HE Linlin cHEN Zhiquan HE wing w.Y.ng School of Science Beijing University of Civil Engineering and ArchitectureBeijing 100044China School of computer Science and Engineering South China University of TechnologyGuangzhou 510006China Aerospace Information Research Institute Chinese Academy of SciencesBeijing 100094China Guangdong Key Laboratory of Intelligent Information Processing Shenzhen 518060China Institute of Big Data Modeling and Technology Beijing University of Civil Engineering and ArchitectureBeijing 100044China

Low-rank matrix decomposition with first-order total variation(TV)regularization exhibits excellent performance in exploration of image *** advantage of its excellent performance in image denoising,we apply it to improve the robustness of deep neural ***,although TV regularization can improve the robustness of the model,it reduces the accuracy of normal samples due to its *** our work,we develop a new low-rank matrix recovery model,called LRTGV,which incorporates total generalized variation(TGV)regularization into the reweighted low-rank matrix recovery *** the proposed model,TGV is used to better reconstruct texture information without *** reweighted nuclear norm and Li-norm can enhance the global structure ***,the proposed LRTGV can destroy the structure of adversarial noise while re-enhancing the global structure and local texture of the *** solve the challenging optimal model issue,we propose an algorithm based on the alternating direction method of *** results show that the proposed algorithm has a certain defense capability against black-box attacks,and outperforms state-of-the-art low-rank matrix recovery methods in image restoration.

关键词： Total generalized variation Low-rank matrix Alternating direction method of multipliers Adversarial example

weakly Supervised Object Localization with Background Suppression Erasing for Art Authentication and copyright Protection

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Machine Intelligence Research 2024年第1期21卷 89-103页

作者： chaojie wu Mingyang Li Ying Gao Xinyan Xie wing w.Y.ng Ahmad Musyafa School of computer Science and Engineering South China University of TechnologyGuangzhou 511442China Guangdong Provincial Key Laboratory of Artificial Intelligence in Medical Image Analysis and Application Guangdong Provincial People's HospitalGuangzhou 510180China

The problem of art forgery and infringement is becoming increasingly prominent,since diverse self-media contents with all kinds of art pieces are released on the Internet every *** art paintings,object detection and localization provide an efficient and ef-fective means of art authentication and copyright ***,the acquisition of a precise detector requires large amounts of ex-pensive pixel-level *** alleviate this,we propose a novel weakly supervised object localization(wSOL)with background su-perposition erasing(BSE),which recognizes objects with inexpensive image-level ***,integrated adversarial erasing(IAE)for vanilla convolutional neural network(cNN)dropouts the most discriminative region by leveraging high-level semantic ***,a background suppression module(BSM)limits the activation area of the IAE to the object region through a self-guidance ***,in the inference phase,we utilize the refined importance map(RIM)of middle features to obtain class-agnostic loc-alization *** experiments are conducted on paintings,cUB-200-2011 and ILSVRc to validate the effectiveness of our BSE.

关键词： weakly supervised object localization erasing method deep learning computer vision art authentication and copyright protection

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膨胀土渠坡降雨入渗现场试验研究

长江科学院院报 2002年第B9期19卷 94-97页

作者：龚壁卫 c.w.w.ng 包承纲詹良通袁俊平长江科学院土工研究所湖北武汉430010 香港科技大学

探讨了降雨入渗对膨胀土渠坡稳定的影响。研究表明,膨胀土的裂隙是控制膨胀土渠坡稳定的重要因素,降雨是诱发滑坡的直接原因。同时,还证明了降雨对膨胀土具有一定的影响范围。

关键词：降雨非饱和土膨胀土现场试验吸力干渠

Learning about good nutrition with the 5-color front-of-package label"Nutri-Score":an experimental study

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Food Science and Human wellness 2024年第3期13卷 1195-1200页

作者： Robin c.Hau Klaus w.Lange University of Applied Sciences Landshut Landshut 84036Germany Faculty of Human Sciences University of RegensburgRegensburg 93040Germany

The Nutri-Score is a 5-color front-of-pack nutrition label designed to provide consumers with an easily understandable guideline to the healthiness of food *** impact that the Nutri-Score may have on consumers'choices is unclear since different experimental paradigms have found vastly different effect *** the present study,we have investigated how student participants change a hypothetical personal 1-daydietary plan after a learning phase during which they learn about the Nutri-Scores of the available food *** were instructed to compose a healthy diet plan in order that the question of whether the NutriScore would improve their ability to compose a healthy dietary plan could be investigated,independent of the question of whether they would apply this knowledge in their ordinary *** found a substantial(cohen's d=0.86)positive impact on nutritional quality(as measured by the Nutrient Profiling System score of the Food Standards Agency)and a medium-sized(cohen's d=0.43)reduction of energy *** content reduction was larger for participants who had initially composed plans with higher energy *** results suggest that the Nutri-Score has the potential to guide consumers to healthier food *** remains unclear,however,whether this potential will be reflected in real-life dietary choices.

关键词： Nutri-Score Front-of-package label Nudge Nutrition Health

Integrins and their potential roles in mammalian pregnancy

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Journal of Animal Science and Biotechnology 2024年第1期15卷 1-19页

作者： Gregory A.Johnson Robert c.Burghardt Fuller w.Bazer Heewon Seo Joe w.cain Department of Veterinary Integrative Biosciences School of Veterinary Medicine and Biomedical SciencesTexas A&M UniversityCollege StationTX 77843‑4459USA Department of Animal Science College of Agriculture and Life SciencesTexas A&M UniversityCollege StationTX 77843‑2471USA

Integrins are a highly complex family of receptors that, when expressed on the surface of cells, can mediate reciprocal cell-to-cell and cell-to-extracellular matrix(EcM) interactions leading to assembly of integrin adhesion complexes(IAcs) that initiate many signaling functions both at the membrane and deeper within the cytoplasm to coordinate processes including cell adhesion, migration, proliferation, survival, differentiation, and metabolism. All metazoan organisms possess integrins, and it is generally agreed that integrins were associated with the evolution of multicellularity, being essential for the association of cells with their neighbors and surroundings, during embryonic development and many aspects of cellular and molecular biology. Integrins have important roles in many aspects of embryonic development, normal physiology, and disease processes with a multitude of functions discovered and elucidated for integrins that directly influence many areas of biology and medicine, including mammalian pregnancy, in particular implantation of the blastocyst to the uterine wall, subsequent placentation and conceptus(embryo/fetus and associated placental membranes) development. This review provides a succinct overview of integrin structure, ligand binding, and signaling followed with a concise overview of embryonic development, implantation, and early placentation in pigs, sheep, humans, and mice as an example for rodents. A brief timeline of the initial localization of integrin subunits to the uterine luminal epithelium(LE) and conceptus trophoblast is then presented, followed by sequential summaries of integrin expression and function during gestation in pigs, sheep, humans, and rodents. As appropriate for this journal, summaries of integrin expression and function during gestation in pigs and sheep are in depth, whereas summaries for humans and rodents are brief. Because similar models to those illustrated in Fig. 1, 2, 3, 4, 5 and 6 are present throughout the sc

关键词： Humans Implantation Integrins Pigs Pregnancy Rodents Sheep

centrifuge Modelling of the Behaviour of a Floating Pile in consolidating Soil

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Centrifuge Modelling of the Behaviour of a Floating Pile in ...

Elevated brain temperature under severe heat exposure impairs cortical motor activity and executive function

中国土木工程学会第九届土力学及岩土工程学术会议

作者： G.c.Y.chan c.J.Lee V.S.H.chan c.w.w.ng c.FLeung The Hong Kong University of Science and Technology Hong Kong The Hong Kong University of Science and Technology Hong Kong The Hong Kong University of Science and Technology Hong Kong The Hong Kong University of Science and Technology Hong Kong The National University of Singapore Singapore

＜正＞ A centrifuge model test was carride out to investigate the behaviour of a floating pile in consolidating soil. Measured soil and plie settlements are presented and deduced dragload on the model pile are compared with the aand β- methods. Insights into the pile behaviour in consolidating soil, the effects of pile tip location , in particular, on pile settlement are reported and discussed.

关键词： centrifuge modelling consolidation downdrag dragload floating pile soil/structure interaction

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Journal of Sport and Health Science 2024年第2期13卷 233-244页

作者： Xiang Ren Tan Mary c.Stephenson Sharifah Badriyah Alhadad Kelvin w.Z.Loh Tuck wah Soong Jason K.w.Lee Ivan c.c.Low Health and Social Sciences Singapore Institute of TechnologySingapore 138683Singapore Human Potential Translational Research Programme Yong Loo Lin School of MedicineNational University of SingaporeSingapore 117597Singapore centre for Translational Magnetic Resonance Research Yong Loo Lin School of MedicineNational University of SingaporeSingapore 117549Singapore Department of Physiology Yong Loo Lin School of MedicineNational University of SingaporeSingapore 117593Singapore Heat Resilience and Performance centre Yong Loo Lin School of MedicineNational University of SingaporeSingapore 117510Singapore N.1 Institute for Health National University of SingaporeSingapore 117456Singapore campus for Research Excellence and Technological Enterprise(cREATE) Singapore 138602Singapore

Background:Excessive heat exposure can lead to hyperthermia in humans,which impairs physical performance and disrupts cognitive *** heat is a known physiological stressor,it is unclear how severe heat stress affects brain physiology and ***:Eleven healthy participants were subjected to heat stress from prolonged exercise or warm water immersion until their rectal temperatures(T_(re))attained 39.5℃,inducing exertional or passive hyperthermia,*** a separate trial,blended ice was ingested before and during exercise as a cooling *** were compared to a control condition with seated rest(normothermic).Brain temperature(T_(br)),cerebral perfusion,and task-based brain activity were assessed using magnetic resonance imaging ***:T_(br)in motor cortex was found to be tightly regulated at rest(37.3℃±0.4℃(mean±SD))despite fluctuations in T_(re).with the development of hyperthermia,T_(br)increases and dovetails with the rising T_(re).Bilateral motor cortical activity was suppressed during high-intensity plantarflexion tasks,implying a reduced central motor drive in hyperthermic participants(T_(re)=38.5℃±0.1℃).Global gray matter perfusion and regional perfusion in sensorimotor cortex were reduced with passive *** function was poorer under a passive hyperthermic state,and this could relate to compromised visual processing as indicated by the reduced activation of left lateral-occipital ***,ingestion of blended ice before and during exercise alleviated the rise in both T_(re)and T_(bc)and mitigated heat-related neural ***:Severe heat exposure elevates T_(br),disrupts motor cortical activity and executive function,and this can lead to impairment of physical and cognitive performance.

关键词： Brain functional activity cognition Heat stress Hyperthermia Motor function

Superplasticity of fine-grained Mg-10Li alloy prepared by severe plastic deformation and understanding its deformation mechanisms

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Journal of Magnesium and Alloys 2024年第1期12卷 316-331页

作者： H.T.Jeong S.w.Lee w.J.Kim Department of Materials Science and Engineering Hongik UniversityMapo-guSangsu-dong 72-1Seoul 121-791Republic of Korea

The superplastic behavior and associated deformation mechanisms of a fine-grained Mg-10.1 Li-0.8Al-0.6Zn alloy(LAZ1011)with a grain size of 3.2μm,primarily composed of the Bccβphase and a small amount of the HcPαphase,were examined in a temperature range of 473 K to 623 *** microstructural refinement of this alloy was achieved by employing high-ratio differential speed *** best superplasticity was achieved at 523 K and at strain rates of 10^(-4)-5×10^(-4)s^(-1),where tensile elongations of 550±600%were *** the heating and holding stage of the tensile samples prior to tensile loading,a significant increase in grain size was observed at temperatures above 573 ***,it was important to consider this effect when analyzing and understanding the superplastic deformation behavior and *** the investigated strain rate range,the superplastic flow at low strain rates was governed by lattice diffusion-controlled grain boundary sliding,while at high strain rates,lattice diffusion-controlled dislocation climb creep was the rate-controlling deformation *** was concluded that solute drag creep is unlikely to *** the late stages of deformation at 523 K,it was observed that grain boundary sliding led to the agglomeration of theαphase,resulting in significant strain *** mechanism maps were constructed forβ-Mg-Li alloys in the form of 2D and 3D formats as a function of strain rate,stress,temperature,and grain size,using the constitutive equations for various deformation mechanisms derived based on the data of the current tests.

关键词： Magnesium-lithium alloy Superplasticity Severe plastic deformation Grain size Grain growth