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A low-floor bit-mapping scheme for LDPC coded BICM for 5G and beyond systems

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Science China(Information Sciences) 2023年第10期66卷 263-277页

作者： Mingyang zhu Ming jiang Chunming ZHAO Lijie hu Xiaodong XU National Mobile Communications Research Laboratory Southeast University Purple Mountain Laboratories China Mobile Research Institute

This paper proposes a low-floor bit-mapping(LFBM) scheme for bit-interleaved coded modulation(BICM) systems to meet more stringent quality of service requirements of 5G and beyond. For highefficiency transmissions, we consider the 5G low-density parity-check codes with high-order 2m-quadrature amplitude modulations(QAMs). The proposed LFBM scheme overcomes plenty of trapping sets induced by the bit interleaver, which focuses on the waterfall performance too aggressively. When the high-order QAM is used, the row-column interleaver specified by the 5G standard is such a bit interleaver. The LFBM scheme only optimizes the rule of mapping an m-bit tuple output by the row-column interleaver to a modulation symbol, rather than the entire bit interleaver. Therefore, the optimized bit mapper is actually an m-bit permutation module concatenated with the original bit interleaver employed in the current 5G BICM systems.The simulation results confirm that the LFBM scheme can lower the error floor of the 5G BICM system by approximately two orders of magnitude, while with negligible performance loss in the waterfall region.

关键词： bit-interleaved coded modulation low-density parity-check codes error floors bit mapping high-order modulation

Study on Quantitative Precipitation Estimation by Polarimetric Radar Using Deep Learning

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Advances in Atmospheric Sciences 2024年第6期41卷 1147-1160页

作者： jiang huANGFU Zhiqun hu Jiafeng ZHENG Lirong WANG Yongjie zhu State Key Lab of Severe Weather Chinese Academy of Meteorological SciencesBeijing 100081China Meteorological observatory of jiangxi Province Nanchang 330096China Hebei Meteorological Disaster Prevention and Environmental Meteorological Center Shijiazhuang 050021China School of Atmospheric Sciences Chengdu University of Information TechnologyChengdu 610225China

Accurate radar quantitative precipitation estimation(QPE)plays an essential role in disaster prevention and mitigation.In this paper,two deep learning-based QPE networks including a single-parameter network and a multi-parameter network are designed.Meanwhile,a self-defined loss function(SLF)is proposed during modeling.The dataset includes Shijiazhuang S-band dual polarimetric radar(CINRAD/SAD)data and rain gauge data within the radar’s 100-km detection range during the flood season of 2021 in North China.Considering that the specific propagation phase shift(KDP)has a roughly linear relationship with the precipitation intensity,KDP is set to 0.5°km^(-1 )as a threshold value to divide all the rain data(AR)into a heavy rain(HR)and light rain(LR)dataset.Subsequently,12 deep learning-based QPE models are trained according to the input radar parameters,the precipitation datasets,and whether an SLF was adopted,respectively.The results suggest that the effects of QPE after distinguishing rainfall intensity are better than those without distinguishing,and the effects of using SLF are better than those that used MSE as a loss function.A Z-R relationship and a ZH-KDP-R synthesis method are compared with deep learning-based QPE.The mean relative errors(MRE)of AR models using SLF are improved by 61.90%,51.21%,and 56.34%compared with the Z-R relational method,and by 38.63%,42.55%,and 47.49%compared with the synthesis method.Finally,the models are further evaluated in three precipitation processes,which manifest that the deep learning-based models have significant advantages over the traditional empirical formula methods.

关键词： polarimetric radar quantitative precipitation estimation deep learning single-parameter network multi-parameter network

Controlled TiO2 coating on hollow glass microspheres and their reflective thermal insulation properties

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Particuology 2020年第2期18卷 33-39页

作者： Jie Long Chongwen jiang Jundong zhu Quzhi Song jiang hu College of Chemistry and Chemical Engineering Central South UniversityHunan 410083China hunan Provincial Key Laboratory of Efficient and Clean Utilization of Manganese Resources Central South UniversityHunan 410083China

Hollow glass microspheres(HGMs)have great potential in building energy-saving and industrial insulation.Anatase TiO2-modified HGMs were prepared by a sol-gel method in acetic acid-ethanol solution.Scanning electron microscopy,X-ray diffraction,zeta-potential measurements,nitrogen-sorption measurements,and Fourier-transform infrared and ultraviolet-visible-near-infrared diffuse reflectance spectroscopies showed that the alkali modification of the HGMs greatly influenced the loading and microstructure of the TiO2 film.The TiO2 loading could be accurately controlled by ethanol addition and the TiO2 coating time.A mechanism for the TiO2 coating of the HGM surface is proposed.The synergistic action of hydrogen bonding and electrostatic forces resulted in close contact between the HGMs and TiO2 sol at pH 3.5.The effects of different TiO2 loading rates on the reflective and thermal insulation properties were studied.The near-infrared reflectance of 15.9%TiO2 coated on HGMs was 96.27%,and the inner surface temperature of the composite pigment coated on aluminum board was reduced by 22.4℃.The TiO2/HGM composite pigments exhibited excellent solar reflective and thermal insulation properties,so have potential in the construction of exterior walls and roofs.

关键词： Hollow glass microspheres TiO2 loading Sol-gel Reflective insulation Surface treatment

A method for reducing thermal injury during the ureteroscopic holmium laser lithotripsy

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Asian Journal of Urology 2023年第1期10卷 89-95页

作者： Xiaoliang zhu Feiping Li Xixi hu Haiping Li Songjiang Wu Haihong jiang Department of Urology and Andrology Taizhou Hospital of Zhejiang Province Affiliated to Wenzhou Medical UniversityTaizhouChina Department of Urology and Andrology The First Affiliated Hospital of Wenzhou Medical UniversityWenzhouChina

Objective:Many studies have demonstrated the heat effect from the holmium laser lithotripsy can cause persistent thermal injury to the ureter.The purpose of this study was to elucidate the use of a modified ureteral catheter with appropriate firing and irrigation to reduce the thermal injury to the“ureter”during the ureteroscopic holmium laser lithotripsy in vitro.Methods:An in vitro lithotripsy was performed using a modified catheter(5 Fr)as the entrance for the irrigation and the holmium laser fiber while using the remaining space in the ureteroscopic channel as an outlet.Different laser power settings(10 W,20 W,and 30 W)with various firing times(3 s,5 s,and 10 s)and rates of irrigation(15 mL/min,20 mL/min,and 30 mL/min)were applied in the experiment.Temperature changes in the“ureter”were recorded with a thermometer during and after the lithotripsy.Results:During the lithotripsy,the local highest mean temperature was 60.3℃ and the lowest mean temperature was 26.7℃.When the power was set to 10 w,the temperature was maintained below 43℃ regardless of laser firing time or irrigation flow.Regardless of the power or firing time selected,the temperature was below 43℃ at the rate of 30 mL/min.There was a significant difference in temperature decrease when continuous 3 s drainage after continuous firing(3 s,5 s,or 10 s)compared to with not drainage(p<0.05)except for two conditions of 0.5 J×20 Hz,30 mL/min,firing 5 s,and 1.0 J×10 Hz,30 mL/min,firing 5 s.Conclusion:Our modified catheter with timely drainage reducing hot irrigation may significantly reduce the local thermal injury effect,especially along with the special interrupted-time firing setting during the simulated holmium laser procedure.

关键词： Modified catheter Holmium laser Lithotripsy Thermal injury

Deep Learning-based Moving Object Segmentation:Recent Progress and Research Prospects

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Machine Intelligence Research 2023年第3期20卷 335-369页

作者： Rui jiang Ruixiang zhu hu Su Yinlin Li Yuan Xie Wei Zou College of Information Engineering Shanghai Maritime UniversityShanghai201306China School of Computer Science and Technology East China Normal UniversityShanghai200062China Research Center of Precision Sensing and Control Institute of AutomationChinese Academy of SciencesBeijing100190China State Key Laboratory for Management and Control of Complex Systems Institute of AutomationChinese Academy of SciencesBeijing100190China

Moving object segmentation(MOS),aiming at segmenting moving objects from video frames,is an important and challenging task in computer vision and with various applications.With the development of deep learning(DL),MOS has also entered the era of deep models toward spatiotemporal feature learning.This paper aims to provide the latest review of recent DL-based MOS methods proposed during the past three years.Specifically,we present a more up-to-date categorization based on model characteristics,then compare and discuss each category from feature learning(FL),and model training and evaluation perspectives.For FL,the methods reviewed are divided into three types:spatial FL,temporal FL,and spatiotemporal FL,then analyzed from input and model architectures aspects,three input types,and four typical preprocessing subnetworks are summarized.In terms of training,we discuss ideas for enhancing model transferability.In terms of evaluation,based on a previous categorization of scene dependent evaluation and scene independent evaluation,and combined with whether used videos are recorded with static or moving cameras,we further provide four subdivided evaluation setups and analyze that of reviewed methods.We also show performance comparisons of some reviewed MOS methods and analyze the advantages and disadvantages of reviewed MOS methods in terms of technology.Finally,based on the above comparisons and discussions,we present research prospects and future directions.

关键词： Moving object segmentation(MOS) change detection background subtraction deep learning(DL) video understanding

Insight on corrosion behavior of a Cu-P-Cr-Ni steel with different Ni contents by electrochemical and periodic immersion corrosion experiments

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Journal of Iron and Steel Research(International) 2023年第3期30卷 580-590页

作者： Zhi-wei Lian Tian-en Peng Shuang hu Bo He Xue-wen hu Tao zhu Bo jiang School of Materials Science and Engineering University of Science and Technology BeijingBeijing 100083China Technical Center Ma’anshan Iron&Steel Co.Ltd.Ma’anshan 243041AnhuiChina

Corrosion behavior of Cu-P-Cr-Ni weathering steels with different nickel contents was studied by periodic immersion corrosion test for 72 h.The mass loss method was used to evaluate the weatherability of weathering steel.The rust layers formed on weathering steel were characterized by scanning electron microscopy,X-ray diffraction,electron probe microanalysis,X-ray photoelectron spectroscopy,and electrochemical measurements.The results of periodic immersion corrosion test for 72 h showed that the mass loss rates of Cu-P-Cr-0.14Ni steel and Cu-P-Cr-0.04Ni steel were 1.57 and 1.61 g/(m^(2)h),respectively.According to the electrochemical experiment,the corrosion potentials of the two tested steels at the initial stage of corrosion were-0.6852 and-0.7037 V,respectively.With the corrosion time reaching 72 h,the corrosion potential difference between the two tested steels was gradually reduced.In the initial stage,NiO was formed in the rust layer and can dramatically promote the crystallization of corrosion products to improve the stability of the rust layer.After periodic immersion corrosion test for 72 h,Ni element had no obvious effect.At this time,it was mainly the enrichment of Cu and Cr elements in the form of CuO and Cr_(2)O_(3)in the rust layer that could further protect the matrix.

关键词： Weathering steel Ni Electrochemical experiment Periodic immersion corrosion Corrosion behavior

High-chromium vanadium-titanium magnetite all-pellet integrated burden optimization and softening-melting behavior based on flux pellets

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International Journal of Minerals,Metallurgy and Materials 2024年第3期31卷 498-507页

作者： Bojian Chen Tao jiang Jing Wen Guangdong Yang Tangxia Yu Fengxiang zhu Peng hu School of Metallurgy Northeastern UniversityShenyang 110819China Key Laboratory for Ecological Metallurgy of Multimetallic Mineral(Ministry of Education) Northeastern UniversityShenyang 110819China Liaoning Key Laboratory for Metallurgical Sensor and Technology Shenyang 110819China State key laboratory of vanadium and titanium resources comprehensive utilization Panzhihua 617000China

High-chromium vanadium-titanium magnetite(HVTM)is a crucial polymetallic-associated resource to be developed.The allpellet operation is a blast furnace trend that aims to reduce carbon dioxide emissions in the future.By referencing the production data of vanadium-titanium magnetite blast furnaces,this study explored the softening-melting behavior of high-chromium vanadium-titanium magnetite and obtained the optimal integrated burden based on flux pellets.The results show that the burden with a composition of 70wt%flux pellets and 30wt%acid pellets exhibits the best softening-melting properties.In comparison to that of the single burden,the softening-melting characteristic temperature of this burden composition was higher.The melting interval first increased from 307 to 362℃and then decreased to 282℃.The maximum pressure drop(ΔPmax)decreased from 26.76 to 19.01 kPa.The permeability index(S)dropped from 4643.5 to 2446.8 kPa·℃.The softening-melting properties of the integrated burden were apparently improved.The acid pellets played a role in withstanding load during the softening process.The flux pellets in the integrated burden exhibited a higher slag melting point,which increased the melting temperature during the melting process.The slag homogeneity and the TiC produced by over-reduction led to the gas permeability deterioration of the single burden.The segregation of the flux and acid pellets in the HVTM proportion and basicity mainly led to the better softening-melting properties of the integrated burden.

关键词： high-chromium vanadium-titanium magnetite softening-melting properties all pellets integrated burden flux pellets

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A Novel Multi-Granularity Flexible-Grid Switching Optical-Node Architecture

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China Communications 2023年第1期20卷 209-217页

作者： Zhenfang huang Bo zhu Mingchen zhu Mengyue jiang Xinting Song Jiawei Zhao Zheng Wang Fangren hu College of Electronic and Optical Engineering&College of Microelectronics Nanjing University of Posts and TelecommunicationsNanjing 210023China SUFA Technology Industry Co. Ltd.CNNCSuzhou 215001China

A novel multi-granularity flexible-grid switching optical-node architecture is proposed in this paper.In our system,the photonic lanterns are used as mode division multiplexing/demultiplexing(MD-Mux/MD-Demux)for selecting mode.The wavelength division multiplexer/demultiplexer(WDMux/WD-Demux)and the fiber bragg gratings(FBGs)are used to select wavelength channels with the various grid.The experimental results show that the transmission bandwidth covers the C+L band,the average transmission loss is-13.4 dB,and the average crosstalk is-30.5 dB.The optical-node architecture is suit for mode division multiplexing(MDM)optical communication system.

关键词： optical node multi-granularity switching flexible-grid switching

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Hippocampus:Molecular,Cellular,and Circuit Features in Anxiety

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Neuroscience Bulletin 2023年第6期39卷 1009-1026页

作者： hu-jiang Shi Shuang Wang Xin-Ping Wang Rui-Xin Zhang Li-Juan zhu Key Laboratory of Developmental Genes and human Diseases MOEDepartment of Histology and EmbryologySchool of MedicineSoutheast UniversityNanjing210009China Shanghai Mental Health Center Shanghai Jiao Tong University School of MedicineShanghai201108China

Anxiety disorders are currently a major psychiatric and social problem,the mechanisms of which have been only partially elucidated.The hippocampus serves as a major target of stress mediators and is closely related to anxiety modulation.Yet so far,its complex anatomy has been a challenge for research on the mechanisms of anxiety regulation.Recent advances in imaging,virus tracking,and optogenetics/chemogenetics have permitted elucidation of the activity,connectivity,and function of specific cell types within the hippocampus and its connected brain regions,providing mechanistic insights into the elaborate organization of the hippocampal circuitry underlying anxiety.Studies of hippocampal neurotransmitter systems,including glutamatergic,GABAergic,cholinergic,dopaminergic,and serotonergic systems,have contributed to the interpretation of the underlying neural mechanisms of anxiety.Neuropeptides and neuroinflammatory factors are also involved in anxiety modulation.This review comprehensively summarizes the hippocampal mechanisms associated with anxiety modulation,based on molecular,cellular,and circuit properties,to provide tailored targets for future anxiety treatment.

关键词： Anxiety Hippocampus Excitatory neurons Interneurons Neural circuit