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Robo Cloud: augmenting robotic visions for open environment modeling using Internet knowledge

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Science China(Information Sciences) 2018年第5期61卷 19-34页

作者： Yiying LI Huaimin WANG Bo DING Wei Zhou College of Computer National University of Defense Technology

Modeling an open environment that contains unpredictable objects is a challenging problem in the field of robotics. In traditional approaches, when a robot encounters an unknown object, a mistake will inevitably be added to the robot’s environmental model, severely constraining the robot’s autonomy,and possibly leading to disastrous consequences in certain settings. The abundant knowledge accumulated on the Internet has the potential to remedy the uncertainties that result from encountering with unknown objects. However, robotic applications generally pay considerable attention to quality of service(Qo S).For this reason, directly accessing the Internet, which can be unpredictable, is generally not acceptable.Robo Cloud is proposed as a novel approach to environment modeling that takes advantage of the Internet without sacrificing the critical properties of Qo S. Robo Cloud is a "mission cloud–public cloud" layered cloud organization model in which the mission cloud provides Qo S-available environment modeling capability with built-in prior knowledge while the public cloud is the existing services provided by the Internet. The "cloud phase transition" mechanism seeks help from the public cloud only when a request is outside the knowledge of the mission cloud and the Qo S cost is acceptable. We have adopted semantic mapping, a typical robotic environment modeling task, to illustrate and substantiate our approach and key mechanism. Experiments using open 2 D and 3 D datasets with real robots have demonstrated that Robo Cloud is able to augment robotic visions for open environment modeling.

关键词： Internet-augmented environment modeling uncertainty robotic visions semantic mapping robotic software cloud robotics

Automatic facade recovery from single nighttime image

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Frontiers of Computer Science 2020年第1期14卷 95-104页

作者： Yi zhou Qichuan GENG Zhong zhou wei WU State Key Laboratory of Virtual Reality Technology and Systems Beihang UniversityBeijing 100083China

Nighttime images are difficult to process due to insufficient brightness,lots of noise,and lack of details.Therefore,they are always removed from time-lapsed image analysis.It is interesting that nighttime images have a unique and wonderful building features that have robust and salient lighting cues from human activities.Lighting variation depicts both the statistical and individual habitation,and it has an inherent man-made repetitive structure from architectural theory.Inspired by this,we propose an automatic nighttime fa?ade recovery method that exploits the lattice structures of window lighting.First,a simple but efficient classification method is employed to determine the salient bright regions,which may be lit windows.Then we groupwindows into multiple lattice proposals with respect to fa?ades by patch matching,followed by greedily removing overlapping lattices.Using the horizon constraint,we solve the ambiguous proposals problem and obtain the correct orientation.Finally,we complete the generated fa?ades by filling in the missing windows.This method is well suited for use in urban environments,and the results can be used as a good single-view compensation method for daytime images.The method also acts as a semantic input to other learning-based 3D image reconstruction techniques.The experiment demonstrates that our method works well in nighttime image datasets,and we obtain a high lattice detection rate of 82.1%of 82 challenging images with a low mean orientation error of 12.1±4.5 degrees.

关键词： facade recovery nighttime images lattice detection

Model of Underground Ant Nest Structure Using Static and Dynamic Finite Element Analysis

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Acta Mechanica Solida Sinica 2018年第6期31卷 717-730页

作者： Wenjun Qu Wei Zhou Peng Zhu Zhi Zhang Department of Structural Engineering Tongji University Shanghai 200092 China The High School Affiliated with Shanghai University Shanghai 200444 Chinch

This paper focuses on the structural characteristics of ant nests,which are complex structures.Natural underground ant nests generally have good air circulation,pressure resistance, waterproof properties,thermal insulation and a favorable temperature and relative humidity. Additionally,ant nests are often surrounded by trees and other natural barriers.In this study, the natural underground ant nests of Iridomyrmex anceps were gathered from different collection sites.Manual cutting and frozen computer numerical control milling were performed on the ant nests in a laboratory.The internal structure of each nest was measured and recorded,and then, the 2D and 3D numerical structure models of the Iridomyrmex anceps nest were created.The static and dynamic simulation analysis of an underground ant nest structure was performed by using finite element analysis software (ABAQUS),and the mechanical properties of the ant nest were discussed.The underground ant nest structure effectively resisted the additional stress due to external static and live loads,and the ant nest was not completely destroyed.

关键词： Underground ant nest Iridomyrmex anceps Frozen CNC milling Finite element analysis Static simulation Dynamic simulation

Debranching enzymes decomposed corn arabinoxylan into xylooligosaccharides and achieved prebiotic regulation of gut microbiota in broiler chickens

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Journal of Animal Science and Biotechnology 2023年第4期14卷 1485-1500页

作者： wei Wu Huajin zhou Yanhong Chen Yuming Guo Jianmin Yuan State Key Laboratory of Animal Nutrition College of Animal Science and TechnologyChina Agricultural University2 Yuanmingyuan West RoadHaidian DistrictBeijing 100193PR China

Background Corn arabinoxylan(AX)is a complicated and multibranched antinutritional factor,thereby proving the use of endo-xylanase(EX)to be marginally valid.This study focused on specific types of AX-degrading enzymes(ADEs)to exert the synergy of debranching enzymes and track the prebiotic potential of enzymatic hydrolysates.This study investigated the effects of ADEs on the growth performance,intestinal histomorphology,absorption functions,changes in polysaccharide components,fermentation,and gut microbiota of broiler chickens.Five hundred seventysix five-day-old Arbor Acres male broiler chickens were randomly allocated into eight treatments with six replicates each.Corn basal diets supplemented with or without enzymes were fed for a 21-day period,specifically including EX,its compatible use with arabinofuranosidase(EXA)or ferulic acid esterase(EXF),and compound groups with the above three enzymes(XAF).Results Specific ADEs stimulated the jejunal villus height and goblet cell number and evidently decreased the crypt depth(P<0.05),while the ratio of ileal villus height to crypt depth was significantly increased in EXF(P<0.05).Maltase activities of ileal mucosa in XAF groups were extremely enhanced(P<0.01),and EX boosted the activity of Na+-K+ATPase in the small intestine(P<0.01).The insoluble AX concentrations comparatively lessened,thereby notably raising the sundry xylooligosaccharide(XOS)yield in the ileal chyme(P<0.05),which was dominant in xylobiose and xylotriose.Improvements in the abundance and diversity of ileal microbial communities within the EXA,EXF,and XAF treatments were observed(P<0.05).Positive correlations between microbiota and XOS were revealed,with xylobiose and xylotriose being critical for ten beneficial bacteria(P<0.05).EXF increased the BWG and FCR of broiler chickens in this phase(P<0.05),which was attributed to the thriving networks modified by Lactobacillus.The intracecal contents of acetic acid,butyric acid,and propionic acid were greatly enhanced in most ADE groups,such as EXF(P<0.05)

关键词： Arabinoxylan Corn Prebiotic Specific xylanase Xylooligosaccharide

The design and investigation of hydrogel-based metamaterials with ultra large negative hygroscopic expansion ratio

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International Journal of Smart and Nano Materials 2022年第1期13卷 114-129,I0007页

作者： Lian-Hua Ma Su-Dong Wang Jia Liu Hong Gao Wei Zhou Non-destructive Testing Laboratory School of Quality and Technical SupervisionHebei UniversityBaodingHebei071002China National&local Joint Engineering Research Center of Metrology Instrument and System Hebei UniversityBaodingHebei071002China Hebei Key Laboratory of Energy Metering and Safety Testing Technology Hebei UniversityBaodingHebei071002China Material Reliability Center China academy of space technologyBeijing100029China

A design strategy for a mechanical metamaterial with large negative hygroscopic expansion(NHE)was proposed in this paper.Different from the reported structures,the present metamaterial is designed by constructing repeated lattice microstructure consisting of curved ligaments incorporating hydrogel active layers and polymer support layers and straight polymer bars.When immersed in the solution environment,the swelling of hydrogel layer of such composite structure induces the reversed bending of the ligament,leading to the overall ultra-large shrink(negative expansion)deformation of the metamaterial.Through the new structural design,large NHE effects can be achieved.The theoretical investigation and finite element analysis(FEA)were conducted to demonstrate the large negative expansion effects of such metamaterial.The results showed that the effective NHE ratio of the metamaterial is dependent of the curvature of the curved ligament and the size of both the ligament and the connecting rod.The ultra-large NHE ratios about−80%for the 2D structure and−90%for the 3D version can be obtained by adopting the structural parameters.The newly designed metamaterials have potential applications in medical and other fields.

关键词： Hydrogel-based metamaterial structural design negative hygroscopic expansion active deformation

C-CORE:Clustering by Code Representation to Prioritize Test Cases in Compiler Testing

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Computer Modeling in Engineering & Sciences 2024年第5期139卷 2069-2093页

作者： Wei Zhou Xincong Jiang Chuan Qin School of Electronic Information and Electrical Engineering Shanghai Jiao Tong UniversityShanghai200240China Hikvision Research Institute Hangzhou Hikvision Digital Technology Co.Ltd.Hangzhou310051China

Edge devices,due to their limited computational and storage resources,often require the use of compilers for program optimization.Therefore,ensuring the security and reliability of these compilers is of paramount importance in the emerging field of edge AI.One widely used testing method for this purpose is fuzz testing,which detects bugs by inputting random test cases into the target program.However,this process consumes significant time and resources.To improve the efficiency of compiler fuzz testing,it is common practice to utilize test case prioritization techniques.Some researchers use machine learning to predict the code coverage of test cases,aiming to maximize the test capability for the target compiler by increasing the overall predicted coverage of the test cases.Nevertheless,these methods can only forecast the code coverage of the compiler at a specific optimization level,potentially missing many optimization-related bugs.In this paper,we introduce C-CORE(short for Clustering by Code Representation),the first framework to prioritize test cases according to their code representations,which are derived directly from the source codes.This approach avoids being limited to specific compiler states and extends to a broader range of compiler bugs.Specifically,we first train a scaled pre-trained programming language model to capture as many common features as possible from the test cases generated by a fuzzer.Using this pre-trained model,we then train two downstream models:one for predicting the likelihood of triggering a bug and another for identifying code representations associated with bugs.Subsequently,we cluster the test cases according to their code representations and select the highest-scoring test case from each cluster as the high-quality test case.This reduction in redundant testing cases leads to time savings.Comprehensive evaluation results reveal that code representations are better at distinguishing test capabilities,and C-CORE significantly enhances testing efficiency.Across four datasets,C-COR

关键词： Compiler testing test case prioritization code representation

Slightly ruthenium doping enables better alloy nanoparticle exsolution of perovskite anode for high-performance direct-ammonia solid oxide fuel cells

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Journal of Materials Science & Technology 2022年第30期125卷 51-58页

作者： Xiandong Xiong Jian Yu Xiaojian Huang Dan Zou Yufei Song Meigui Xu Ran Ran wei Wang Wei Zhou Zongping Shao State Key Laboratory of Materials-Oriented Chemical Engineering College of Chemical EngineeringNanjing Tech UniversityNanjing 210009China Department of Mechanical and Aerospace Engineering The Hong Kong University of Science and TechnologyClear Water BayHong KongChina WA School of Mines:Minerals Energy and Chemical Engineering(WASM-MECE)Curtin UniversityPerthWA 6845Australia

Fuel flexibility is one of the most distinguished advantages of solid oxide fuel cells(SOFCs)over other low-temperature fuel cells.Furthermore,the combination of ammonia fuel and SOFCs technology should be a promising clean energy system after considering the high energy density,easy transportation/storage,matured synthesis technology and carbon-free nature of NH_(3) as well as high efficiency of SOFCs.However,the large-scale applications of direct-ammonia SOFCs(DASOFCs)are strongly limited by the inferior anti-sintering capability and catalytic activity for ammonia decomposition reaction of conventional nickel-based cermet anode.Herein,a slightly ruthenium(Ru)doping in perovskite oxides is proposed to promote the alloy nanoparticle exsolution,enabling better DA-SOFCs with enhanced power outputs and operational stability.After treating Ru-doped Pr_(0.6)Sr_(0.4)Co_(0.2)Fe_(0.75)Ru_(0.05)O_(3-δ) single-phase perovskite in a reducing atmosphere,in addition to the formation of two layered Ruddlesden-Popper perovskites and Pr_(2)O_(3) nanoparticles(the same as the Ru-free counterpart,Pr_(0.6)Sr_(0.4)Co_(0.2)Fe_(0.8)O_(3-δ)),the exsolution of CoFeRu-based alloy nanoparticles is remarkably promoted.Such reduced Pr_(0.6)Sr0.4Co_(0.2)Fe_(0.75)Ru_(0.05)O_(3-δ) composite anode shows superior catalytic activity and stability for NH_(3) decomposition reaction as well as anti-sintering capability in DA-SOFCs to those of reduced Pr0.6Sr0.4Co0.2Fe0.8O_(3-δ)due to the facilitated nanoparticle exsolution and stronger nanoparticle/substrate interaction.This work provides a facile and effective strategy to design highly active and durable anodes for DA-SOFCs,promoting large-scale applications of this technology.

关键词： Solid oxide fuel cell Ammonia Exsolution Perovskite anode Ruthenium doping

Improved decadal climate prediction in the North Atlantic using EnOI-assimilated initial condition

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Science Bulletin 2017年第16期62卷 1142-1147页

作者： Min wei Qingquan Li Xiaoge Xin Wei Zhou Zhenyu Han Yong Luo Zongci Zhao Ministry of Education Key Laboratory for Earth System Modeling Department of Earth System ScienceTsinghua UniversityBeijing 100084China Joint Center for Global Change Studies Beijing 100875China National Meteorological Information Center China Meteorological AdministrationBeijing 100081China Laboratory for Climate Studies National Climate CenterChina Meteorological AdministrationBeijing 100081China Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science and TechnologyNanjing 210044China State Key Laboratory of Tropical Oceanography South China Sea Institute of OceanologyChinese Academy of SciencesGuangzhou 510301China

Decadal prediction experiments of Beijing Climate Center climate system model version 1.1(BCCCSM1.1) participated in Coupled Model Intercomparison Project Phase 5(CMIP5) had poor skill in extratropics of the North Atlantic, the initialization of which was done by relaxing modeled ocean temperature to the Simple Ocean Data Assimilation(SODA) reanalysis data. This study aims to improve the prediction skill of this model by using the assimilation technique in the initialization. New ocean data are firstly generated by assimilating the sea surface temperature(SST) of the Hadley Centre Sea Ice and Sea Surface Temperature(Had ISST) dataset to the ocean model of BCC-CSM1.1 via Ensemble Optimum Interpolation(EnOI). Then a suite of decadal re-forecasts launched annually over the period 1961–2005 is carried out with simulated ocean temperature restored to the assimilated ocean data.Comparisons between the re-forecasts and previous CMIP5 forecasts show that the re-forecasts are more skillful in mid-to-high latitude SST of the North Atlantic. Improved prediction skill is also found for the Atlantic multi-decadal oscillation(AMO), which is consistent with the better skill of Atlantic meridional overturning circulation(AMOC) predicted by the re-forecasts. We conclude that the EnOI assimilation generates better ocean data than the SODA reanalysis for initializing decadal climate prediction of BCC-CSM1.1 model.

关键词：气候预测模型北大西洋数据同化年代际海洋温度初始化过程气候系统模式海洋表面温度

Recent advances in electrocatalytic generation of indole-derived radical cations and their applications in organic synthesis

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Chinese Chemical Letters 2024年第4期35卷 106-123页

作者： Wei Zhou Xi Chen Lin Lu Xian-Rong Song Mu-Jia Luo Qiang Xiao Key Laboratory of Organic Chemistry of Jiangxi Province Jiangxi Science&Technology Normal UniversityNanchang 330013China

Indole-derived radical cations, open-shell reactive species, display distinctive dual reactivity due to the carbon-centered radical and more electrophilic carbocation, which frequently appear in a variety of single electron oxidation reactions for synthesizing structurally diverse functionalized indoles and indolines. Electrocatalysis is considered as a synthetically attractive and environmentally friendly alternative for driving the single electron oxidation of indoles. Remarkable achievements in electrocatalytic indolederived radical cation-mediated indole functionalization have been realized so far. This review comprehensively summarizes the recent progresses in the applications of electrocatalytic indole radical cations,including C(sp~2)–H functionalization, dearomative 2,3-difunctionalization, and ring-opening reaction, emphasizing the vital single electron oxidation steps of indoles, the substrates scope and limitations, and the reaction mechanisms.

关键词： Electrocatalysis Indole radical cation C-H functionalizatin Dearomative 2 3-difunctionalization