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Airborne sparse flight array SAR 3D imaging based on compressed sensing in frequency domain

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Journal of Systems Engineering and Electronics 2023年第1期34卷 56-67页

作者： TIAN He DONG Chunzhu yin Hongcheng yuan Li Science and Technology on Electromagnetic Scattering Laboratory Bejing Insititute of Environment FeaturesBeijing 100854China

In airborne array synthetic aperture radar(SAR), the three-dimensional(3D) imaging performance and cross-track resolution depends on the length of the equivalent array. In this paper, Barker sequence criterion is used for sparse flight sampling of airborne array SAR, in order to obtain high cross-track resolution in as few times of flights as possible. Under each flight, the imaging algorithm of back projection(BP) and the data extraction method based on modified uniformly redundant arrays(MURAs) are utilized to obtain complex 3D image pairs. To solve the side-lobe noise in images, the interferometry between each image pair is implemented, and compressed sensing(CS) reconstruction is adopted in the frequency domain. Furthermore, to restore the geometrical relationship between each flight, the phase information corresponding to negative MURA is compensated on each single-pass image reconstructed by CS. Finally,by coherent accumulation of each complex image, the high resolution in cross-track direction is obtained. Simulations and experiments in X-band verify the availability.

关键词： three-dimensional(3D)imaging synthetic aperture radar(SAR) sparse flight interferometry compressed sensing(CS)

Research on Credit Regulation Mechanism of E-commerce Platform Based on Evolutionary Game Theory

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Journal of Systems Science and Systems Engineering 2024年第3期33卷 330-359页

作者： Zeguo Qiu Yuchen yin Yao yuan Yunhao Chen School of Computer and Information Engineering Harbin University of CommerceHarbin150028China School of Management Harbin University of CommerceHarbin150028China

In the growing e-commerce industry,the problem of malicious business operations has become increasingly prominent,exposing many problems such as weak supervision of e-commerce platforms and no way for consumers to complain.In order to solve the problems of counterfeit and shoddy products on e-commerce platforms and promote the sustainable development of the e-commerce industry in China,this paper constructs a three-party evolutionary game model of e-commerce platforms,merchants,and consumers,investigates the influence of each influencing factor on each party’s strategy choice,and provides targeted suggestions to e-commerce platforms based on relevant factors.Finally,the impact of several important parameters on the equilibrium solution is discussed through sensitivity analysis.The results show that:1)the smaller the cost difference between active and negative regulation,the more the e-commerce platform tends to active regulation strategy,but increasing fines for dishonest merchants and consumer complaints have little impact on the e-commerce platform;2)increasing consumer compensation,creating an honest business environment,and reducing the cost of honest business all help companies tend to operate in good faith;3)the only factor that affects the tendency of consumer complaint strategies is the cost of complaints.The loss suffered by silence and the compensation given to consumers have little effect on consumers’tendency to complain strategy.The results can provide theoretical guidance for participants to make useful strategic decisions in the e-commerce market.

关键词： Evolutionary game e-commerce data simulation

Microwave synthesis of duplexα/β-SiAlON ceramic cutting inserts:Modifying m,n,z values,synthesis temperature,and excess Y_(2)O_(3) synthesis additive

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Journal of Advanced Ceramics 2022年第4期11卷 589-602页

作者： Dongbo HONG Zengbin yin Fuzhou GUO Juntang yuan School of Mechanical Engineering Nanjing University of Science and TechnologyNanjing 210094China Collaborative Innovation Center of High-End Equipment Manufacturing Technology Nanjing University of Science and TechnologyMinistry of Industry and Information TechnologyNanjing 210094China

Duplexα/β-SiAlON ceramic cutting inserts(30α:70β)were synthesized by microwave sintering.The effects of solid solution parameters(m,n,z),synthesis temperature,and amount of excess Y_(2)O_(3) synthesis additive on phase assemblage,microstructure,mechanical properties,and cutting performance were systematically investigated.It was found that increasing m value could improve the formation ofαphase while high z value over 1.0 resulted in the dissolution ofαphase intoβphase and intergranular phase.Increasing the amount of excess Y_(2)O_(3) could promote densification and elongatedβgrain growth;however,the excess Y_(2)O_(3) amount above 4 wt%resulted in substantial crystallization of M'SS phase,thus declining the mechanical properties and wear resistance.The microwave-synthesizedα/β-SiAlON cutting insert with modified parameters(m=1.7,n=1.0,z=0.7,and 3 wt%excess Y_(2)O_(3))was obtained with optimal comprehensive properties,whose tool life was found to increase by approximately 75%in high-speed milling of Inconel 718 superalloy compared to the commercialα/β-SiAlON cutting insert.

关键词： α/β-SiAlON microwave ceramic cutting insert solid solution parameter Y_(2)O_(3)synthesis additive

Flexibility analysis for continuous ibuprofen manufacturing processes

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Chinese Journal of Chemical Engineering 2022年第11期51卷 115-125页

作者： Wenhui Yang Haoyu yin Zhihong yuan Bingzhen Chen State Key Laboratory of Chemical Engineering Department of Chemical EngineeringTsinghua UniversityBeijing 100084China School of Material Science and Engineering Tsinghua UniversityBeijing 100084China Department of Chemical Engineering Tsinghua UniversityBeijing 100084China

Continuous ibuprofen(a widespread used analgesic drug)manufacturing is full of superiorities and is a fertile field both in industry and academia since it can not only effectively treat rheumatic and other chronic and painful diseases,but also shows great potential in dental diseases.As one of central elements of operability analysis,flexibility analysis is in charge of the quantitative assessment of the capability to guarantee the feasible operation in face of variations on uncertain parameters.In this paper,we focus on the flexibility index calculation for the continuous ibuprofen manufacturing process.We update existing state-of-the-art formulations,which traditionally lead to the max-max-max optimization problem,to approach the calculation of the flexibility index with a favorable manner.Advantages regarding the size of the mathematical model and the computational CPU time of the modified method are examined by four cases.In addition to identifying the flexibility index without any consideration of control variables,we also investigate the effects of different combinations of control variables on the flexibility property to reveal the benefits from taking recourse actions into account.Results from systematic investigations are expected to provide a solid basis for the further control system design and optimal operation of continuous ibuprofen manufacturing.

关键词： Continuous manufacturing Pharmaceuticals Mathematical modeling Flexibility analysis Mixed integer programing Optimization

Spark plasma sintering ofα/β-SiAlON ceramic end mill rods:Electro-thermal simulation,microstructure,mechanical properties,and machining performance

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Journal of Advanced Ceramics 2023年第9期12卷 1777-1792页

作者： Fuzhou Guo Zengbin yin Xuelin Li Juntang yuan School of Mechanical Engineering Nanjing University of Science and TechnologyNanjing 210094China Collaborative Innovation Center of High-End Equipment Manufacturing Technology(Nanjing University of Science and Technology) Ministry of Industry and Information TechnologyNanjing 210094China Nanjing Totem Tool Co. Ltd.Nanjing 211215China

Spark plasma sintering(SPS)is a highly efficient method for the preparation ofα/β-SiAlON ceramics.However,the rapid preparation of large-scaleα/β-SiAlON ceramic components with reliable mechanical properties is difficult via SPS due to their near-insulating properties.In this study,high-performanceα/β-SiAlON ceramic end mill rods with large aspect ratios were successfully prepared via SPS.Two different types of sintering processes(namely vertical-round-rod(VRR)and horizontal-square-rod(HSR)processes)were developed,and their effects on the phase composition,microstructure,mechanical properties,and machining performance of theα/β-SiAlON ceramic end mill rods were studied.The electric and temperature field distributions during sintering were studied through an electro–thermal simulation.The simulated and experimental temperature distributions are in good agreement.In contrast to VRR samples,HSR samples with a small axial size show a uniform temperature distribution and satisfactory microstructures within a certain range of dimensions as well as the expected phase composition;furthermore,elongatedβ-SiAlON grains are preferentially oriented in the direction perpendicular to the sintering pressure direction.As a result,the HSR samples exhibit better mechanical properties and machining performance than the VRR samples.

关键词： α/β-SiAlON ceramics spark plasma sintering(SPS) electro-thermal simulation microstructure mechanical properties orientation

Proteomic analysis of trans-hemispheric motor cortex reorganization following contralateral C7 nerve transfer

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Neural Regeneration Research 2018年第2期13卷 331-339页

作者： Yin Yuan Xiu-yue Xu Jie Lao Xin Zhao Department of Hand Surgery Huashan HospitalFudan UniversityShanghaiChina Key Laboratory of Hand Reconstruction Ministry of HealthShanghaiChina Shanghai Key Laboratory of Peripheral Nerve&Microsurgery ShanghaiChina

Nerve transfer is the most common treatment for total brachial plexus avulsion injury. After nerve transfer, the movement of the injured limb may be activated by certain movements of the healthy limb at the early stage of recovery, i.e., trans-hemispheric reorganization. Pre- vious studies have focused on functional magnetic resonance imaging and changes in brain-derived neurotrophic factor and growth asso- ciated protein 43, but there have been no proteomics studies. In this study, we designed a rat model of total brachial plexus avulsion injury involving contralateral C7 nerve transfer. Isobaric tags for relative and absolute quantitation and western blot assay were then used to screen differentially expressed proteins in bilateral motor cortices. We found that most differentially expressed proteins in both cortices of upper limb were associated with nervous system development and function （including neuron differentiation and development, axonogenesis, and guidance）, microtubule and cytoskeleton organization, synapse plasticity, and transmission of nerve impulses. Two key differentially expressed proteins, neurofilament light （NFL） and Thy-1, were identified. In contralateral cortex, the NFL level was upregulated 2 weeks after transfer and downregulated at 1 and 5 months. The Thy-1 level was upregulated from 1 to 5 months. In the affected cortex, the NFL level increased gradually from 1 to 5 months. Western blot results of key differentially expressed proteins were consistent with the proteom- ic findings. These results indicate that NFL and Thy-1 play an important role in trans-hemispheric organization following total brachial plexus root avulsion and contralateral C7 nerve transfer.

关键词： nerve regeneration brachial plexus brain plasticity contralateral C,q cortex reorganization isobaric tags for relative and absolute quantitation proteomics nerve transfer neurofilament light Thy-1 neural regeneration

Diagnosing anomalous characteristics of atmospheric water cycle structure during seasonal-scale drought events:A case study in middle and lower reaches of Yangtze River

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Water Science and Engineering 2022年第2期15卷 103-113页

作者： Hai He Rui Cao Zhi-yong Wu yuan Li Hao yin Fei yuan College of Hydrology and Water Resources Hohai UniversityNanjing 210098China

Anomalous characteristics of the atmospheric water cycle structure are highly significant to the mechanisms of seasonal-scale meteorological droughts.They also play an important role in the identification of indicative predictors of droughts.To better understand the causes of seasonal meteorological droughts in the middle and lower reaches of the Yangtze River(MLRYR),characteristics of the atmospheric water cycle structure at different drought stages were determined using standardized anomalies.The results showed that the total column water vapor(TCWV)was anomalously low during drought occurrence periods.In contrast,there were no anomalous signals at the drought persistence and recovery stages in the MLRYR.Moreover,there was no significant temporal correlation between the TCWV anomaly and seasonal-scale drought index(the 3-month standardized precipitation index(SPI_(3))).During drought events,water vapor that mainly originated from the Bay of Bengal was transported southwest of the MLRYR.Meanwhile,the anomalous signal of water vapor transport was negative at the drought appearance stage.At the drought persistence stage,the negative anomalous signal was the most significant.Water vapor flux divergence in the MLRYR showed significant positive anomalous signals during drought events,and the signal intensity shifted from an increasing to a decreasing trend at different drought stages.In addition,a significant positive correlation existed between the anomaly of water vapor flux divergence and regional SPI_(3).Overall,water vapor flux divergence is more predictive of droughts in the MLRYR.

关键词： Water vapor transport Water vapor flux divergence Standardized anomalies Seasonal-scale drought process Middle and lower reaches of Yangtze River

Enriched environment for offspring improves learning and memory impairments induced by sevoflurane exposure during the second trimester of pregnancy

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Neural Regeneration Research 2022年第6期17卷 1293-1298页

作者： Shao-Wei yin Yi-Lin Meng Chuang Li yuan Wang Department of Obstetrics Shengjing Hospital of China Medical UniversityShenyangLiaoning ProvinceChina Department of Anesthesiology Shengjing Hospital of China Medical UniversityShenyangLiaoning ProvinceChina

Studies in animals indicate that sevoflurane exposure in the second trimester of pregnancy has harmful effects on the learning and memory of offspring.Whether an enriched environment can reverse the damage of sevoflurane exposure in the second trimester of pregnancy on the learning and memory of rat offspring remains unclear.In this study,rats at 14 days of pregnancy were exposed to 3.5%sevoflurane for 2 hours and their offspring were treated with an enriched environment for 20 successive days.We found that the enriched environment for offspring increased nestin and Ki67 levels in hippocampal tissue,increased hippocampal neurogenesis,inhibited glycogen synthase kinase 3βactivity,and increased the expression of cell proliferation-relatedβ-catenin and apoptosis-related Bcl-2,indicating that an enriched environment reduces sevoflurane-induced damage by increasing the proliferation of stem cells in the hippocampus.These findings suggest that an enriched environment can reverse the effects of sevoflurane inhaled by rats during the second trimester of pregnancy on learning and memory of offspring.This study was approved by the Animal Ethics Committee of Shengjing Hospital of China Medical University(approval No.2018PS07K)on January 2,2018.

关键词： apoptosis fetal learning memory neurogenesis offspring proliferation sevoflurane signal pathway

The combination of EGCG with warfarin reduces deep vein thrombosis in rabbits through modulating HIF-1αand VEGF via the PI3K/AKT and ERK1/2 signaling pathways

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Chinese Journal of Natural Medicines 2022年第9期20卷 679-690页

作者： LI Yan GE Jing-Ping MA Ke Yin Yuan-yuan HE Juan GU Jian-Ping Department of Vascular and Interventional Radiology Nanjing First HospitalNanjing Medical UniversityNanjing 210006China Department of Acupuncture Qinhuai District Hospital of Traditional Chinese MedicineNanjing 210000China

Deep venous thrombosis(DVT)poses a major challenge to public health worldwide.Endothelial cell injury evokes inflammatory and oxidative responses that contribute to thrombus formation.Tea polyphenol(TP)in the form of epigallocatechin-3-gallate(EGCG)has anti-inflammatory and oxidative effect that may ameliorate DVT.However,the precise mechanism remains incompletely understood.The current study was designed to investigate the anti-DVT mechanism of EGCG in combination with warfarin(an oral anticoagulant).Rabbits were randomly divided into five groups.A DVT model of rats was established through ligation of the inferior vena cava(IVC)and left common iliac vein,and the animals were orally administered with EGCG,warfarin,or vehicle for seven days.In vitro studies included pretreatment of human umbilical vein endothelial cells(HUVECs)with different concentrations of EGCG for 2 h before exposure to hydrogen peroxide.Thrombus weight and length were examined.Histopathological changes were observed by hematoxylin-eosin staining.Blood samples were collected for detecting coagulation function,including thrombin and prothrombin times,activated partial thromboplastin time,and fibrinogen levels.Protein expression in thrombosed IVCs and HUVECs was evaluated by Western blot,immunohistochemical analysis,and/or immunofluorescence staining.RT-qPCR was used to determine the levels of AGTR-1 and VEGF mRNA in IVCs and HUVECs.The viability of HUVECs was examined by CCK-8 assay.Flow cytometry was performed to detect cell apoptosis and ROS generation was assessed by 2′,7ʹ-dichlorofluorescein diacetate reagent.In vitro and in vivo studies showed that EGCG combined with warfarin significantly reduced thrombus weight and length,and apoptosis in HUVECs.Our findings indicated that the combination of EGCG and warfarin protects HUVECs from oxidative stress and prevents apoptosis.However,HIF-1αsilencing weakened these effects,which indicated that HIF-1αmay participate in DVT.Furthermore,HIF-1αsilencing significantly up-regulated cell apoptosis and

关键词： Deep vein thrombosis EGCG Warfarin HIF-1α VEGF PI3K/AKT ERK1/2