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Research on Enhanced Contraband Dataset ACXray Based on ETL

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Computers, Materials & Continua 2024年第6期79卷 4551-4572页

作者： Xueping Song jianming yang Shuyu Zhang Jicun Zhang School of Mechanical Engineering Dalian Jiaotong UniversityDalian116028China Neusoft Reach Automotive Technology(Dalian)Co. Ltd.Dalian116085China

To address the shortage of public datasets for customs X-ray images of contraband and the difficulties in deploying trained models in engineering applications,a method has been proposed that employs the Extract-Transform-Load(ETL)approach to create an X-ray dataset of contraband items.Initially,X-ray scatter image data is collected and cleaned.Using Kafka message queues and the Elasticsearch(ES)distributed search engine,the data is transmitted in real-time to cloud servers.Subsequently,contraband data is annotated using a combination of neural networks and manual methods to improve annotation efficiency and implemented mean hash algorithm for quick image retrieval.The method of integrating targets with backgrounds has enhanced the X-ray contraband image data,increasing the number of positive samples.Finally,an Airport Customs X-ray dataset(ACXray)compatible with customs business scenarios has been constructed,featuring an increased number of positive contraband samples.Experimental tests using three datasets to train the Mask Region-based Convolutional Neural Network(Mask R-CNN)algorithm and tested on 400 real customs images revealed that the recognition accuracy of algorithms trained with Security Inspection X-ray(SIXray)and Occluded Prohibited Items X-ray(OPIXray)decreased by 16.3%and 15.1%,respectively,while the ACXray dataset trained algorithm’s accuracy was almost unaffected.This indicates that the ACXray dataset-trained algorithm possesses strong generalization capabilities and is more suitable for customs detection scenarios.

关键词： X-ray contraband ETL data enhancement dataset

A Modified Tikhonov Regularization Method for a Cauchy Problem of the Biharmonic Equation

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Journal of Mathematical Research with Applications 2024年第3期44卷 359-386页

作者： Fan yang jianming XU Xiaoxiao LI School of Science Lanzhou University of Technology

In this paper, the Cauchy problem of biharmonic equation is considered. This problem is ill-posed, i.e., the solution(if exists) does not depend on the measurable data. Firstly, we give the conditional stability result under the a priori bound assumption for the exact solution.Secondly, a modified Tikhonov regularization method is used to solve this ill-posed problem.Under the a priori and the a posteriori regularization parameter choice rule, the error estimates between the regularization solutions and the exact solution are obtained. Finally, some numerical examples are presented to verify that our method is effective.

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Prefrontal cortical circuits in anxiety and fear:an overview

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Frontiers of Medicine 2022年第4期16卷 518-539页

作者： Yihua Chen Nengyuan Hu jianming yang Tianming Gao State Key Laboratory of Organ Failure Research Key Laboratory of Mental Health of the Ministry of EducationGuangdong−Hong Kong−Macao Greater Bay Area Center for Brain Science and Brain-Inspired IntelligenceGuangdong Province Key Laboratory of Psychiatric DisordersDepartment of NeurobiologySchool of Basic Medical SciencesSouthern Medical UniversityGuangzhou 510515China

Pathological anxiety is among the most difficult neuropsychiatric diseases to treat pharmacologically,and it represents a major societal problem.Studies have implicated structural changes within the prefrontal cortex(PFC)and functional changes in the communication of the PFC with distal brain structures in anxiety disorders.Treatments that affect the activity of the PFC,including cognitive therapies and transcranial magnetic stimulation,reverse anxiety-and fear-associated circuit abnormalities through mechanisms that remain largely unclear.While the subjective experience of a rodent cannot be precisely determined,rodent models hold great promise in dissecting well-conserved circuits.Newly developed genetic and viral tools and optogenetic and chemogenetic techniques have revealed the intricacies of neural circuits underlying anxiety and fear by allowing direct examination of hypotheses drawn from existing psychological concepts.This review focuses on studies that have used these circuit-based approaches to gain a more detailed,more comprehensive,and more integrated view on how the PFC governs anxiety and fear and orchestrates adaptive defensive behaviors to hopefully provide a roadmap for the future development of therapies for pathological anxiety.

关键词： prefrontal cortex anxiety fear neural circuits optogenetics DREADD

Comparative analysis between single-train passing and double-train intersection in a tunnel

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2024年第5期25卷 429-442页

作者： jianming DU Qian FANG Xuan ZHANG Hualao WANG Bridge and Tunnel Research Center Research Institute of Highway Ministry of TransportBejing 100088China Tunnel and Underground Engineering Research Center of Ministry of Education Beijing Jiaotong UniversityBeijing 00044China

Aerodynamic pressure significantly impacts the scientific evaluation of tunnel service performance.The aerodynamic pressure of two trains running in a double-track tunnel is considerably more complicated than that of a single train.We used the numerical method to investigate the difference in aerodynamic pressure between a single train and two trains running in a double-track tunnel.First,the numerical method was verified by comparing the results of numerical simulation and on-site monitoring.Then,the characteristics of aerodynamic pressure were studied.Finally,the influence of various train-tunnel factors on the characteristics of aerodynamic pressure was investigated.The results show that the aerodynamic pressure variation can be divided into stage I:irregular pressure fluctuations before the train tail leaves the tunnel exit,and stage II:periodic pressure declines after the train tail leaves the tunnel exit.In addition,the aerodynamic pressure simultaneously jumps positively or drops negatively for a single train or two trains running in double-track tunnel scenarios.The pressure amplitude in the two-train case is higher than that for a single train.The maximum positive peak pressure difference(P_(STP))and maximum negative peak pressure difference(P_(STN))increase as train speed rises to the power from 2.256 to 2.930 in stage I.The P_(STP) and P_(STN) first increase and then decrease with the increase of tunnel length in stage I.The P_(STP) and P_(STN) increase as the blockage ratio rises to the power from 2.032 to 2.798 in stages I and II.

关键词： Railway tunnel Aerodynamic effect Pressure characteristic Train speed Tunnel length Blockage ratio

EHMT2 promotes tumorigenesis in GNAQ/11-mutant uveal melanoma via ARHGAP29-mediated RhoA pathway

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Acta Pharmaceutica Sinica B 2024年第3期14卷 1187-1203页

作者： Yongyun Li Tianyu Zhu Jie yang Qianqian Zhang Shiqiong Xu Shengfang Ge Renbing Jia jianming Zhang Xianqun Fan Department of Ophthalmology Ninth People’s HospitalShanghai Jiao Tong University School of MedicineShanghai 200001China Shanghai Key Laboratory of Orbital Diseases and Ocular Oncology Shanghai 200001China National Research Center for Translational Medicine(Shanghai) State Key Laboratory of Medical GenomicsShanghai Institute of HematologyRuijin HospitalShanghai Jiao Tong University School of MedicineShanghai 200025China Institute of Translational Medicine Zhangjiang Institute for Advanced StudyShanghai Jiao Tong UniversityShanghai 200240China

Constitutive activation of GNAQ/11 is the initiative oncogenic event in uveal melanoma(UM).Direct targeting GNAQ/11 has yet to be proven feasible as they are vital for a plethora of cellular functions.In search of genetic vulnerability for UM,we found that inhibition of euchromatic histone lysine methyltransferase 2(EHMT2)expression or activity significantly reduced the proliferation and migration capacity of cancer cells.Notably,elevated expression of EHMT2 had been validated in UM samples.Furthermore,Kaplan-Meier survival analysis indicated high EHMT2 protein level was related to poor recurrence-free survival and a more advanced T stage.Chromatin immunoprecipitation sequencing analysis and the following mechanistic investigation showed that ARHGAP29 was a downstream target of EHMT2.Its transcription was suppressed by EHMT2 in a methyltransferasedependent pattern in GNAQ/11-mutant UM cells,leading to elevated RhoA activity.Rescuing constitutively active RhoA in UM cells lacking EHMT2 restored oncogenic phenotypes.Simultaneously blocking EHMT2 and GNAQ/11 signaling in vitro and in vivo showed a synergistic effect on UM growth,suggesting the driver role of these two key molecules.In summary,our study shows evidence for an epigenetic program of EHMT2 regulation that influences UM progression and indicates inhibiting EHMT2 and MEK/ERK simultaneously as a therapeutic strategy in GNAQ/11-mutant UM.

关键词： Uveal melanoma EHMT2 RhoA pathway ARHGAP29 G protein GNAQ GNA11

Efficient degradation of aqueous dichloromethane by an enhanced microbial electrolysis cell:Degradation kinetics,microbial community and metabolic mechanisms

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Journal of Environmental Sciences 2024年第5期139卷 150-159页

作者： Meng Wu Di Zhao Bing Gu ZiruWang Jun Hu Zhiliang Yu jianming Yu College of Environment College of Biotechnology and BioengineeringCollaborative Innovation Center of Yangtze River Delta Region Green PharmaceuticalsZhejiang University of TechnologyHangzhou 310014China Shentuo Environment(Hangzhou)Co.Ltd. Hangzhou 311121China Zhejiang Tianyi Environmental Co.Ltd. Hangzhou 310000China

Dichloromethane(DCM)has been listed as a toxic and harmful water pollutant,and its re moval needs attention.Microbial electrolysis cells(MECs)are viewed as a promising alterna tive for pollutant removal,which can be strengthened from two aspects:microbial inocula tion and acclimation.In this study,the MEC for DCM degradation was inoculated with the ac tive sludge enhanced by Methylobacterium rhodesianum H13(strain H13)and then acclimated in the form of a microbial fuel cell(MFC).Both the introduction of strain H13 and the initi ation in MFC form significantly promoted DCM degradation.The degradation kinetics were fitted by the Haldane model,with V_(max),K_(h),K_(i)and v_(max)values of 103.2 mg/L/hr,97.8 mg/L268.3 mg/L and 44.7 mg/L/hr/cm^(2),respectively.The cyclic voltammogram implies that DCM redox reactions became easier with the setup of MEC,and the electrochemical impedance spectrogram shows that the acclimated and enriched microbes reduced the charge transfe resistance from the electrode to the electrolyte.In the biofilm,the dominant genera shifted from Geobacter to Hyphomicrobium in acclimation stages.Moreover,Methylobacterium played an increasingly important role.DCM metabolism mainly occurred through the hydrolytic glutathione S-transferase pathway,given that the gene dcmA was identified rather than the dhlA and P450/MO.The exogenous electrons facilitated the reduction of GSSG,directly o indirectly accelerating the GSH-catalyzed dehalogenation.This study provides support fo the construction of an efficient and stable MEC for DCM removal in water environment.

关键词： Dichloromethane Microbial electrolysis cells Metabolic pathways Electron transfer Degradation kinetics

Cooling load characteristics of indoor spaces conditioned by decoupled radiant cooling unit with low radiant temperature

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Building Simulation 2022年第12期15卷 2067-2079页

作者： Yuying Liang Nan Zhang Huijun Wu Xinhua Xu jianming yang Gongsheng Huang Department of Architecture and Civil Engineering City University of Hong KongHong KongChina School of Civil Engineering Guangzhou UniversityGuangzhou 510006China Department of Building Environment&Energy Engineering Huazhong University of Science and TechnologyWuhanChina School of Automation Guangdong Polytechnic Normal UniversityGuangzhou 510665China

Decoupled radiant cooling units(DRCUs)are capable of increasing the cooling capacity without increasing condensation risks even using a much lower cooling temperature than conventional radiant cooling units(CRCUs).However,it is unclear whether DRCUs using low radiant cooling temperature will increase the cooling load of the conditioned indoor spaces.In this study,the cooling load characteristics of a thermal chamber conditioned by a DRCU was investigated through developing a steady-state analysis model suitable for both DRCUs and CRCUs.The total/radiative heat flux,as well as the heat exchange with a thermal manikin and walls were analysed under different surface temperatures of DRCUs.The effect of the emissivity of the thermal chamber’external wall on the cooling load was also investigated.Results indicated that the cooling load under the DRCU was slightly smaller than that under the CRCU when the same operative environment was created.Decreasing the infrared emissivity of the exterior wall’s inner surface could lead to a significant decrease in the cooling load for both the DRCU and CRCU.By decreasing the wall emissivity from 0.9 to 0.1,the total cooling load of the DRCU can be decreased by 8.4%and the heat gain of the exterior wall decreased by 21.6%.This study serves as a reference for developing the analysis model and understanding the load characteristics when DRCUs are used to create the thermal environment for indoor spaces.

关键词： radiant cooling condensation-free computational fluid dynamics cooling load hot and humid climates

Mechanical behaviors of warm and ice-rich frozen soil stabilized with sulphoaluminate cement

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Journal of Mountain Science 2024年第1期21卷 335-345页

作者： WANG Honglei ZHANG Hu ZHANG jianming ZHANG Qi YIN Zhenhua State Key Laboratory of Frozen Soil Engineering Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China University of Chinese Academy of Sciences Beijing 100049China School of Civil Engineering and Transportation Northeast Forestry UniversityHarbin 150040China National Key Laboratory of Green and Long-Life Road Engineering in Extreme Environment CCCC First Highway Consultants Co.LtdXi'an 710065China Railway Engineering Research Institute China Academy of Railway Sciences Corporation LimitedBeijing 100081China

The warm and ice-rich frozen soil is characterized by high unfrozen water content, low shear strength and large compressibility, which is unreliable to meet the stability requirements of engineering infrastructures and foundations in permafrost regions. In this study, a novel approach for stabilizing the warm and ice-rich frozen soil with sulphoaluminate cement was proposed based on chemical stabilization. The mechanical behaviors of the stabilized soil, such as strength and stress-strain relationship, were investigated through a series of triaxial compression tests conducted at -1.0℃, and the mechanism of strength variations of the stabilized soil was also explained based on scanning electron microscope test. The investigations indicated that the strength of stabilized soil to resist failure has been improved, and the linear Mohr-Coulomb criteria can accurately reflect the shear strength of stabilized soil under various applied confining pressure. The increase in both curing age and cement mixing ratio were favorable to the growth of cohesion and internal friction angle. More importantly, the strength improvement mechanism of the stabilized soil is attributed to the formation of structural skeleton and the generation of cementitious hydration products within itself. Therefore, the investigations conducted in this study provide valuable references for chemical stabilization of warm and ice-rich frozen ground, thereby providing a basis for in-situ ground improvement for reinforcing warm and ice-rich permafrost foundations by soil-cement column installation.

关键词： Permafrost regions Frozen soil Mechanical behavior Chemical stabilization Ground improvement Ground modification

Surface Passivation and Energetic Modification Suppress Nonradiative Recombination in Perovskite Solar Cells

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Nano-Micro Letters 2022年第7期14卷 32-42页

作者： Wei Dong Wencheng Qiao Shaobing Xiong jianming yang Xuelu Wang Liming Ding Yefeng Yao Qinye Bao Shanghai Key Laboratory of Magnetic Resonance East China Normal UniversityShanghai 200241People’s Republic of China School of Physics and Electronic Science East China Normal UniversityShanghai 200241People’s Republic of China Center for Excellence in Nanoscience(CAS) Key Laboratory of Nanosystem and Hierarchical Fabrication(CAS)National Center for Nanoscience and TechnologyBeijing 100190People’s Republic of China Collaborative Innovation Center of Extreme Optics Shanxi UniversityTaiyuan 030006ShanxiPeople’s Republic of China

Surface passivation via post-treatment is an important strategy for improving power conversion efficiency and operational stability of perovskite solar cells.However,so far the interaction mechanisms between passivating additive and perovskite are not well understood.Here,we report the atomic-scale interaction of surface passivating additive 2,2-difluoroethylammonium bromine(2FEABr)on the MAPbI_(3).It is found that the bulky 2FEA+cations tend to distribute at film surface,while the Br−anions diffuse from surface into bulk.A combination of 19F,207Pb,and 2H solid-state NMR further reveal the Br−anions’partial substitution for the I−sites,the restricted motion of partial MA+cations,and the firmed perovskite lattices,which would improve charge transport and stability of the perovskite films.Optical spectroscopy and ultraviolet photoelectron spectroscopy demonstrate that the 2FEABr induced surface passivation and energetic modification suppress the nonradiative recombination loss.These findings enable the efficiency of the p-i-n structured PSC significantly increasing from 19.44 to 21.06%,accompanied by excellent stability.Our work further establishes more knowledge link between passivating additive and PSC performance.

关键词： Passivation Solid-state NMR Charge transport Perovskite solar cell