检索结果-南通市图书馆

Lipidomic remodeling during mammalian preimplantation embryonic development

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Life Metabolism 2024年第2期3卷 3-5页

作者： Qingran kong Shaorong Gao Zhejiang Provincial Key Laboratory of Medical Genetics Key Laboratory of Laboratory MedicineMinistry of EducationSchool of Laboratory Medicine and Life SciencesWenzhou Medical UniversityWenzhouZhejiang 325035China Clinical and Translational Research Center of Shanghai First Maternity and Infant Hospital Shanghai Key Laboratory of Signaling and Disease ResearchFrontier Science Center for Stem Cell ResearchSchool of Life Sciences and TechnologyTongji UniversityShanghai 200092China

The dynamic changes in lipids during early embryonic development in mammals have not yet been comprehensively investi*** a recent paper published in Nature Cell Biology,Zhang et *** the dynamic lipid landscapes during preimplantation embryonic development in mice and *** highlight the crucial role of lipid unsaturation in regulating embryogenesis.

关键词： Lipid al. lipids

Temperature prediction model in multiphase flow considering phase transition in the drilling operations

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Petroleum Science 2024年第3期21卷 1969-1979页

作者： Yang Zhang Yong-An Li Xiang-Wei kong Hao Liu Teng-Fei Sun College of Mechanical and Electrical Engineering Beijing University of Chemical TechnologyBeijing 100027China School of Petroleum Engineering Yangtze UniversityWuhan430000HubeiChina

The study considers gas compression properties,gas slippage,back pressure(BP),phase transition(PT),well depth,and differences in gas-liquid physical properties.A new temperature model for multiphase flow is proposed by considering phase transition in the drilling *** mathematical model of multiphase flow is solved using the finite difference method with annulus mesh division for grid nodes,and a module for multiphase flow calculation and analysis is *** results indicate that the temperature varies along the annulus with the variation of gas influx at the bottom of the *** the process of controlled pressure drilling,as gas slips along the annulus to the wellhead,its volume continuously expands,leading to an increase in the gas content within the annulus,and consequently,an increase in the pressure drop caused by gas *** temperature increases with the increase in BP and decreases in gas influx rate and wellbore *** gas influx,the thermal conductivity coefficient for the gas-drilling mud two phases is significantly weakened,resulting in a considerable change in temperature along the *** the context of MPD,the method of slightly changing the temperature along the annulus by controlling the back pressure is feasible.

关键词： Managed pressure drilling Phase transition Temperature Gas-drilling mud two phase

Underwater image clarifying based on human visual colour constancy using double-opponency

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

CAAI Transactions on Intelligence Technology 2024年第3期9卷 632-648页

作者： Bin kong Jing Qian Pinhao Song Jing Yang Amir Hussain Institute of Intelligent Machines Chinese Academy of SciencesHefeiChina Peng Cheng Laboratory ShenzhenChina Anhui Key Laboratory of Biomimetic Sensing and Advanced Robot Technology HefeiChina University of Science and Technology of China HefeiChina Peking University Shenzhen Graduate School ShenzhenChina Edinburgh Napier University EdinburghScotland

Underwater images are often with biased colours and reduced contrast because of the absorption and scattering effects when light propagates in *** images with degradation cannot meet the needs of underwater *** main problem in classic underwater image restoration or enhancement methods is that they consume long calcu-lation time,and often,the colour or contrast of the result images is still *** of using the complicated physical model of underwater imaging degradation,we propose a new method to deal with underwater images by imitating the colour constancy mechanism of human vision using ***,the original image is converted to the LMS *** the signals are linearly combined,and Gaussian convolutions are per-formed to imitate the function of receptive fields(RFs).Next,two RFs with different sizes work together to constitute the double-opponency ***,the underwater light is estimated to correct the colours in the *** contrast stretching on the luminance is *** show that the proposed method can obtain clarified underwater images with higher quality than before,and it spends significantly less time cost compared to other previously published typical methods.

关键词： computers computer vision image processing image reconstruction

Two kinds of average approximation accuracy

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

CAAI Transactions on Intelligence Technology 2024年第2期9卷 481-490页

作者： Qingzhao kong Wanting Wang Dongxiao Zhang Wenbin Zhang Department of Science Jimei UniversityXiamenChina Digital Fujian Big Data Modeling and Intelligent Computing Institute Jimei UniversityXiamenChina Department of Computer Science Michigan Technological UniversityHoughtonMichiganUSA

Rough set theory places great importance on approximation accuracy,which is used to gauge how well a rough set model describes a target ***,traditional approximation accuracy has limitations since it varies with changes in the target concept and cannot evaluate the overall descriptive ability of a rough set *** overcome this,two types of average approximation accuracy that objectively assess a rough set model’s ability to approximate all information granules is *** first is the relative average approximation accuracy,which is based on all sets in the universe and has several basic *** second is the absolute average approximation accuracy,which is based on undefinable sets and has yielded significant *** also explore the relationship between these two types of average approximation ***,the average approximation accuracy has practical applications in addressing missing attribute values in incomplete information tables.

关键词： rough sets rough set theory

A TRUST-REGION METHOD FOR SOLVING TRUNCATED COMPLEX SINGULAR VALUE DECOMPOSITION

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Computational Mathematics 2024年第4期42卷 999-1031页

作者： Jiaofen Li Lingchang kong Xuefeng Duan Xuelin Zhou Qilun Luo School of Mathematics and Computing Science Guangri Colleges and Universities Key Laboratory of Data Analysis and ComputationGuangri Key Laboratory of Automatic Detecting Technology and InstrumentsGuilin University of Electronic TechnologyCenter for Applied Mathematics of Guangci(GUET)Guilin 541004China School of Mathematical Sciences South China Normal UniversityGuangzhou 510000China School of Mathematics and Computing Science Guilin University of Electronic TechnologyGuilin 541004China School of Mathematics and Computing Science Guangri Colleges and Universities Key Laboratory of Data Analysis and ComputationGuilin University of Electronic TechnologyCenter for Applied Mathematics of Guangri(GUET)Guilin 541004China School of Mathematics and Statistics Yunan UniversityKunming 650000China

The truncated singular value decomposition has been widely used in many areas of science including engineering,and statistics,*** this paper,the original truncated complex singular value decomposition problem is formulated as a Riemannian optimiza-tion problem on a product of two complex Stiefel manifolds,a practical algorithm based on the generic Riemannian trust-region method of Absil et *** presented to solve the underlying problem,which enjoys the global convergence and local superlinear conver-gence *** experiments are provided to illustrate the efficiency of the proposed *** with some classical Riemannian gradient-type methods,the existing Riemannian version of limited-memory BFGS algorithms in the MATLAB toolbox Manopt and the Riemannian manifold optimization library ROPTLIB,and some latest infeasible methods for solving manifold optimization problems,are also provided to show the merits of the proposed approach.

关键词： Truncated singular value decomposition Riemannian optimization Trust-region method

Recent advances in multimodal sensing integration and decoupling strategies for tactile perception

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Materials Futures 2024年第2期3卷 85-103页

作者： Huijun kong Weiyan Li Zhongqian Song Li Niu School of Chemical Engineering and Technology Sun Yat-sen UniversityZhuhai 519082People’s Republic of China School of Chemistry and Pharmaceutical Engineering c/o College of Artificial Intelligence and Big Data for Medical SciencesShandong First Medical University&Shandong Academy of Medical SciencesJinan 250117People’s Republic of China

Human skin perceives external environmental stimulus by the synergies between the subcutaneous tactile *** electronics with multiple sensing capabilities by mimicking the function of human skin are of significance in health monitoring and artificial *** last decade has witnessed unprecedented development and convergence between multimodal tactile sensing devices and soft *** these advances,traditional flexible electronics achieve multimodal tactile sensing for pressure,strain,temperature,and humidity by integrating monomodal sensing devices *** strategy results in high energy consumption,limited integration,and complex manufacturing *** multimodal sensors and crosstalk-free sensing mechanisms have been proposed to bridge the gap between natural sensory system and artificial perceptual *** this review,we provide a comprehensive summary of tactile sensing mechanism,integration design principles,signal-decoupling strategies,and current applications for multimodal tactile ***,we highlight the current challenges and present the future perspectives to promote the development of multimodal tactile perception.

关键词： multimodal tactile sensing integration multifunctional materials and mechanisms signal decoupling applications of multimodal sensory system

An Underwater Target Detection Algorithm Based on Attention Mechanism and Improved YOLOv7

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Computers, Materials & Continua 2024年第2期78卷 2829-2845页

作者： Liqiu Ren Zhanying Li Xueyu He Lingyan kong Yinghao Zhang College of Information Science and Engineering Dalian Polytechnic UniversityDalian116034China

For underwater robots in the process of performing target detection tasks,the color distortion and the uneven quality of underwater images lead to great difficulties in the feature extraction process of the model,which is prone to issues like error detection,omission detection,and poor ***,this paper proposed the CER-YOLOv7(CBAM-EIOU-RepVGG-YOLOv7)underwater target detection *** improve the algorithm’s capability to retain valid features from both spatial and channel perspectives during the feature extraction phase,we have added a Convolutional Block Attention Module(CBAM)to the backbone *** Reparameterization Visual Geometry Group(RepVGG)module is inserted into the backbone to improve the training and inference *** Efficient Intersection over Union(EIoU)loss is also used as the localization loss function,which reduces the error detection rate and missed detection rate of the *** experimental results of the CER-YOLOv7 algorithm on the UPRC(Underwater Robot Prototype Competition)dataset show that the mAP(mean Average Precision)score of the algorithm is 86.1%,which is a 2.2%improvement compared to the *** feasibility and validity of the CER-YOLOv7 are proved through ablation and comparison experiments,and it is more suitable for underwater target detection.

关键词： Deep learning underwater object detection improved YOLOv7 attention mechanism

Printed Circuit Board (PCB) Surface Micro Defect Detection Model Based on Residual Network with Novel Attention Mechanism

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Computers, Materials & Continua 2024年第1期78卷 915-933页

作者： Xinyu Hu Defeng kong Xiyang Liu Junwei Zhang Daode Zhang School of Mechanical Engineering Hubei University of TechnologyWuhan430068Chain

Printed Circuit Board(PCB)surface tiny defect detection is a difficult task in the integrated circuit industry,especially since the detection of tiny defects on PCB boards with large-size complex circuits has become one of the *** improve the performance of PCB surface tiny defects detection,a PCB tiny defects detection model based on an improved attention residual network(YOLOX-AttResNet)is ***,the unsupervised clustering performance of the K-means algorithm is exploited to optimize the channel weights for subsequent operations by feeding the feature mapping into the SENet(Squeeze and Excitation Network)attention network;then the improved K-means-SENet network is fused with the directly mapped edges of the traditional ResNet network to form an augmented residual network(AttResNet);and finally,the AttResNet module is substituted for the traditional ResNet structure in the backbone feature extraction network of mainstream excellent detection models,thus improving the ability to extract small features from the backbone of the target detection *** results of ablation experiments on a PCB surface defect dataset show that AttResNet is a reliable and efficient *** Torify the performance of AttResNet for detecting small defects in large-size complex circuit images,a series of comparison experiments are further *** results show that the AttResNet module combines well with the five best existing target detection frameworks(YOLOv3,YOLOX,Faster R-CNN,TDD-Net,Cascade R-CNN),and all the combined new models have improved detection accuracy compared to the original model,which suggests that the AttResNet module proposed in this paper can help the detection model to extract target *** them,the YOLOX-AttResNet model proposed in this paper performs the best,with the highest accuracy of 98.45% and the detection speed of 36 FPS(Frames Per Second),which meets the accuracy and real-time requirements for the detection of tiny defect

关键词： Neural networks deep learning ResNet small object feature extraction PCB surface defect detection

Effect of Frequency on Degradation in BOPP Films Under Repetitively Pulsed Voltage

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

CSEE Journal of Power and Energy Systems 2024年第3期10卷 1280-1290页

作者： Chuansheng Zhang Yu Feng Fei kong Bangdou Huang Cheng Zhang Tao Shao Beijing International S&T Cooperation Base for Plasma Science and Energy Conversion Institute of Electrical EngineeringChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

Operating conditions of film capacitors are complex,and the problem of film insulation failure caused by repetitively pulsed voltage is becoming ever *** of the film under repetitively pulsed voltage cannot be accurately evaluated by the average breakdown electric *** this paper,the effects of pulsed electric field and pulse repetition frequency on the breakdown in biaxially oriented polypropylene(BOPP)films are *** phases of BOPP degradation are proposed based on the voltage amplitude,i.e.,maintenance(M),decline(D),and near-zero(N).Evolution of the BOPP film from degradation to breakdown at different frequencies is ***,transition of discharge mode and elemental composition of the film are *** results show continuous heat generation under repetitive microsecond pulses is the dominant factor for degradation of BOPP *** number of applied pulses and the repetitive stressing time decrease exponentially with increase of *** research can be contributed to the safe and reliable operation of capacitors.

关键词： Aging breakdown film capacitor polypropylene repetitive pulse