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A super resolution target separation and reconstruction approach for single channel sar against deceptive jamming

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Defence Technology（防务技术） 2023年第3期21卷 164-175页

作者： Shi-qi Liu Bing Li Bo Zhao Lei Huang Yue-zhou Wu wei-min bao Guangdong Key Laboratory of Intelligent Information Processing College of Electronic and Information EngineeringShenzhen UniversityShenzhen518060China School of Electrical Engineering Southwest Jiaotong UniversityChengdu611756China State Key Laboratory of Millimeter Waves Southeast UniversityNanjing210096China School of Computer Science Civil Aviation Flight University of ChinaGuanghan618307China China Aerospace Science and Technology Corporation Beijing100048China

The excellent remote sensing ability of synthetic aperture radar(SAR)will be misled seriously when it encounters deceptive jamming which possesses high fidelity and fraudulence.In this paper,the dynamic synthetic aperture(DSA)scheme is used to extract the difference between the true and false targets.A simultaneous deceptive jamming suppression and target reconstruction method is proposed for a single channel SAR system to guarantee remote sensing ability.The system model is formulated as a sparse signal recovery problem with an unknown parametric dictionary to be estimated.An iterative reweighted method is employed to jointly handle the dictionary parameter learning and target reconstruction problem in an majorization-minimization framework,where a surrogate function majorizing the Gaussian entropy in the objective function is introduced to circumvent its non-convexity.After dictionary parameter learning,the grid mismatching problem in a fixed grid based method is avoided.Therefore,the proposed method can reap a super resolution result.Besides,a simple yet effective DSA section scheme is developed for the SAR data excerpting,in which only two DSAs are required.Experimental results about location error and reconstruction power error reveal that the proposed method is able to achieve a good performance in deceptive jamming suppression.

关键词： channel resolution separation

Prognostic scores in primary biliary cholangitis patients with advanced disease

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世界胃肠外科杂志:英文版(电子版) 2023年第8期15卷 1774-1783页

作者： Juan Feng Jia-min Xu Hai-Yan Fu Nan Xie wei-min bao Ying-Mei Tang Department of Gastroenterology The Second Affiliated Hospital of Kunming Medical UniversityKunming 650101Yunnan ProvinceChina Department of General Surgery Yunnan Provincial First People’s HospitalKunming 650032Yunnan ProvinceChina

BACKGROUND Due to the chronic progressive disease characteristics of primary biliary cholangitis(PBC),patients with advanced PBC should not be ignored.Most prognostic score studies have focused on early stage PBC.AIM To compare the prognostic value of various risk scores in advanced PBC to help PBC patients obtain more monitoring and assessment.METHODS This study considered patients diagnosed with PBC during hospitalization between 2015 and 2021.The clinical stage was primarily middle and late,and patients usually took ursodeoxycholic acid(UDCA)after diagnosis.The discriminatory performance of the scores was assessed with concordance statistics at baseline and after 1 year of UDCA treatment.Telephone follow-up was conducted to analyze the course and disease-associated outcomes.The follow-up deadline was December 31,2021.We compared the risk score indexes between those patients who reached a composite end point of death or liver transplantation(LT)and those who remained alive at the deadline.The combined performance of prognostic scores in estimating the risk of death or LT after 1 year of UDCA treatment was assessed using Cox regression analyses.Predictive accuracy was evaluated by comparing predicted and actual survival through Kaplan-Meier analyses.RESULTS We included 397 patients who were first diagnosed with PBC during hospitalization and received UDCA treatment;most disease stages were advanced.After an average of 6.4±1.4 years of follow-up,82 patients had died,and 4 patients had undergone LT.After receiving UDCA treatment for 1 year,the score with the best discrimination performance was the Mayo,with a concordance statistic of 0.740(95%confidence interval:0.690-0.791).The albumin-bilirubin,GLOBE,and Mayo scores tended to overestimate transplant-free survival.Comparing 7 years of calibration results showed that the Mayo score was the best model.CONCLUSION The Mayo,GLOBE,UK-PBC,and ALBI scores demonstrated comparable discriminating performance for advanced stage PBC.The Mayo score showed optimal discriminator

关键词： Primary biliary cholangitis Prognostic value Liver transplantation Cholangitis Mayo score

Modified Saint-Venant equations for flow simulation in tidal rivers

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Water Science and Engineering 2012年第1期5卷 34-45页

作者： Xiao-qin ZHANG wei-min bao College of Hydrology and Water Resources Hohai UniversityNanjing 210098P.R.China State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Hohai UniversityNanjing 210098P.R.China

Flow in tidal rivers periodically propagates upstream or downstream under tidal influence. Hydrodynamic models based on the Saint-Venant equations （the SVN model） are extensively used to model tidal rivers. A force-corrected term expressed as the combination of flow velocity and the change rate of the tidal fevel was developed to represent tidal effects in the SVN model. A momentum equation incorporating with the corrected term was derived based on Newton＇s second law. By combing the modified momentum equation with the continuity equation, an improved SVN model for tidal rivers （the ISVN model） was constructed. The simulation of a tidal reach of the Qiantang River shows that the ISVN model performs better than the SVN model. It indicates that the corrected force derived for tidal effects is reasonable; the ISVN model provides an appropriate enhancement of the SVN model for flow simulation of tidal rivers.

关键词： tidal river, tidal effect, dynamic water pressure Saint-Venant equations corrected force, flow simulation

Application of isotopic information for estimating parameters in Philip infiltration model

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Water Science and Engineering 2016年第4期9卷 287-292页

作者： Tao Wang Hai-li Xu wei-min bao PowerChina Chengdu Engineering Corporation Limited Chengdu 610072 China State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Hohai University Nanjing 210098 China

minimizing parameter uncertainty is crucial in the application of hydrologic models.Isotopic information in various hydrologic components of the water cycle can expand our knowledge of the dynamics of water flow in the system,provide additional information for parameter estimation,and improve parameter identifiability.This study combined the Philip infiltration model with an isotopic mixing model using an isotopic mass balance approach for estimating parameters in the Philip infiltration model.Two approaches to parameter estimation were compared:(a) using isotopic information to determine the soil water transmission and then hydrologic information to estimate the soil sorptivity,and(b) using hydrologic information to determine the soil water transmission and the soil sorptivity.Results of parameter estimation were verified through a rainfall infiltration experiment in a laboratory under rainfall with constant isotopic compositions and uniform initial soil water content conditions.Experimental results showed that approach(a),using isotopic and hydrologic information,estimated the soil water transmission in the Philip infiltration model in a manner that matched measured values well.The results of parameter estimation of approach(a) were better than those of approach(b).It was also found that the analytical precision of hydrogen and oxygen stable isotopes had a significant effect on parameter estimation using isotopic information.

关键词： Isotopic information Hydrologic information Parameter estimation Philip infiltration model Rainfall infiltration experiment

Test of newly developed conceptual hydrological model for simulation of rain-on-snow events in forested watershed

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Water Science and Engineering 2013年第1期6卷 31-43页

作者： Si-min QU Han LIU Yan-ping CUI Peng SHI wei-min bao Zhong-bo YU State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Hohai University College of Hydrology and Water Resources Hohai University Department of Forest Engineering Resources and ManagementOregon State UniversityCorvallisOR 97331USA

A conceptual hydrological model that links the Xin＇anjiang hydrological model and a physically based snow energy and mass balance model, described as the XINSNOBAL model, was developed in this study for simulating rain-on-snow events that commonly occur in the Pacific Northwest of the United States. The resultant model was applied to the Lookout Creek Watershed in the H. J. Andrews Experimental Forest in the western Cascade Mountains of Oregon, and its ability to simulate streamflow was evaluated. The simulation was conducted at 24-hour and one-hour time scales for the period of 1996 to 2005. The results indicated that runoffand peak discharge could be underestimated if snowpack accumulation and snowmelt under rain-on-snow conditions were not taken into account. The average deterministic coefficient of the hourly model in streamflow simulation in the calibration stage was 0.837, which was significantly improved over the value of 0.762 when the Xin＇anjiang model was used alone. Good simulation performance of the XINSNOBAL model in the WS 10 catchment, using the calibrated parameter of the Lookout Creek Watershed for proxy-basin testing, demonstrates that transplanting model parameters between similar watersheds can orovide a useful tool for discharge forecastin~, in un^au^ed basins.

关键词： Xin ＇anjiang model,＂ snow energy and mass balance model,＂ rain-on-snow event,＂ H. J.Andrews Experimental Forest

Experimental study of relationship between average isotopic fractionation factor and evaporation rate

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Water Science and Engineering 2010年第4期3卷 394-404页

作者： Tao WANG wei-min bao Hai-li XU Zhen ZHU Si-min QU Peng SHI Hai-ying HU Rui-qi FAN Qian LI HydroChina Chengdu Engineering Corporation Chengdu 610072 R R. China State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Hohai University Nanjing 210098 P. R. China School of Civil Engineering and Transportation South China University of Technology Guangzhou 510641 P. R. China

Isotopic fractionation is the basis of tracing the water cycle using hydrogen and oxygen isotopes. Isotopic fractionation factors in water evaporating from free water bodies are mainly affected by temperature and relative humidity, and vary significantly with these atmospheric factors over the course of a day. The evaporation rate （E） can reveal the effects of atmospheric factors. Therefore, there should be a certain functional relationship between isotopic fractionation factors and E. An average isotopic fractionation factor （ t~＊） was defined to describe isotopic differences between vapor and liquid phases in evaporation with time intervals of days. The relationship between or＊ and E based on the isotopic mass balance was investigated through an evaporation pan experiment with no inflow. The experimental results showed that the isotopic compositions of residual water were more enriched with time; tr＊ was affected by air temperature, relative humidity, and other atmospheric factors, and had a strong functional relation with E. The values of 0~＊ can be easily calculated with the known values of E, the initial volume of water in the pan, and isotopic compositions of residual water.

关键词： average isotopic fractionation factor evaporation rate hydrogen and oxygen isotopes

Experimental study on stable isotopic fractionation of evaporating water under varying temperature

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Water Science and Engineering 2009年第2期2卷 11-18页

作者： Hai-ying HU wei-min bao Tao WANG Si-min QU School of Civil Engineering and Transportation South China University of Technology Guangzhou 510641 P. R. China College of Hydrology and Water Resources Hohai University Nanjing 210098 P. R. China

The variation of stable isotope ratios in natural waters provides valuable information that can be used to trace water movement. Evaporation plays a crucial role in determining the variation of stable isotopes. In this paper, several evaporation experiments were conducted in order to study the stable isotopic fractionation mechanism of water and analyze the influence of different temperatures on evaporation fractionation. Three group experiments of water evaporation under different temperatures and initial isotopic values were carried out. The results show that fractionation factors of hydrogen and oxygen may increase with temperature, and the average enrichment degree of hydrogen isotope D is 3.432 times that of oxygen isotope 18O. The results also show that the isotopic composition of the initial water has little influence on water evaporation fractionation, which is mainly affected by the state variables in the evaporation process, such as temperature. This research provides experimental data for further understanding the evaporation fractionation mechanism.

关键词： water evaporation hydrogen and oxygen isotopes fractionation mechanism temperature, experimental study

Kinetics of phytohemaglutinin-induced IFN-γ and TNF-a expression in peripheral blood mononuclear cells from patients with chronic hepatitis B after liver transplantation

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World Journal of Gastroenterology 2005年第29期11卷 4574-4578页

作者： Ying-Mei Tang min-Hu Chen Gui-Hua Chen Chang-Jie Cai Xiao-Shun He min-Giang Lu wei-min bao Department of Gastroenterology the First Affiliated Hospital of Sun-Yat Sen University Guangzhou 510080 Guangdong Province China Department of Liver Transplantation Center the Third Affiliated Hospital of Sun-Yat Sen University Guangzhou 510080 Guangdong Province China Department of Organ Transplantation the First Affiliated Hospital of Sun-Yat Sen University Guangzhou 510080 Guangdong Province China

AIM: To study the association between host immunity and hepatitis B virus (HBV) recurrence after liver transplantation.METHODS: Peripheral blood mononuclear cells (PBMC) were isolated from 40 patients with hepatitis B and underwent orthotopic liver transplantation (OLT) before and 2, 4, 8 wk after surgery. After being cultured in vitro for 72 h, the levels of INF-γ and TNF-α in culture supernatants were detected with ELISA. At the same time, the quantities of HBV DNA in serum and PBMCs were measured by real time PCR.RESULTS: The levels of INF-γ and TNF-α in PBMC culture supernatants decreased before and 2, 4 wk after surgery in turns (INF-γ 155.52±72.32 ng/L vs14.76±9.88 ng/L vs 13.22±10.35 ng/L, F= 6.946, P = 0.027＜0.05; TNF-α80.839±46.75 ng/L vs 18.59±17.29 ng/L vs9.758±7.96 ng/L,F= 22.61, P= 0.0001＜0.05). The levels of INF-γ and TNF-α were higher in groups with phytohemagglutinin (PHA) than in those without PHA before surgery. However,the difference disappeared following OLT. Furthermore,INF-γ and TNF-α could not be detected in most patients at wk 4 and none at wk 8 after OLT. The HBV detection rate and virus load in PBMlC before and 2, 4 wk after surgery were fluctuated (HBV detected rate: 51.4%, 13.3%, 50% respectively; HBV DNA: 3.55±0.674 log(10) copies/mL vs 3.00±0.329 log(10) copies/mL vs 4.608±1.344 log(10) copies/mL, F= 7.582, P= 0.002＜0.05). HBV DNA in serum was 4.48±1.463 log(10) copies/mL before surgery and ＜103 copies/mL after OLT except for one with 5.72×106 copies/mL 4 wk after OLT who was diagnosed as HBV recurrence.The levels of INF-γ, and TNF-α were lower in patients with a high HBV load than in those with a low HBV load (HBV DNA detected/undetected in PBMCs: IFN-γ 138.08±72.44 ng/L vs 164.24±72.07 ng/L, t = 1.065, P = 0.297＞0.05, TNF-α 80.75±47.30 ng/L vs74.10±49.70 ng/L, t= 0.407, P= 0.686＞0.05; HBV DNA positive/negative: IFN-γ 136.77±70.04 ng/L vs 175.27±71.50 ng/L, t= 1.702, P= 0.097＞0.05; TNF-α 75.37±43.02 ng/L vs 81.53±52.46 ng/L, t = 0.402,P = 0.690＞0.05).CONCLUSION: The yielding of INF-

关键词：动力学 IFN-γ TNF-α 外周血慢性乙型肝炎肝移植

Adaptation of Ocular Opponency Neurons Mediates Attention-Induced Ocular Dominance Plasticity

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Neuroscience Bulletin 2024年第3期40卷 339-349页

作者： Fangxing Song Lili Lyu min bao CAS Key Laboratory of Behavioral Science Institute of PsychologyChinese Academy of SciencesBeijing100101China Department of Psychology University of Chinese Academy of SciencesBeijing100049China Institute of Neuroscience Key Laboratory of Primate NeurobiologyCAS Center for Excellence in Brain Science and Intelligence TechnologyChinese Academy of SciencesShanghai200031China

Previous research has shown that ocular dominance can be biased by prolonged attention to one eye.The ocular-opponency-neuron model of binocular rivalry has been proposed as a candidate account for this phenomenon.Yet direct neural evidence is still lacking.By manipulating the contrast of dichoptic testing gratings,here we measured the steady-state visually evoked potentials(SSVEPs)at the intermodulation frequencies to selectively track the activities of ocular-opponency-neurons before and after the“dichoptic-backward-movie”adaptation.One hour of adaptation caused a shift of perceptual and neural ocular dominance towards the unattended eye.More importantly,we found a decrease in the intermodulation SSVEP response after adaptation,which was significantly greater when high-contrast gratings were presented to the attended eye than when they were presented to the unattended eye.These results strongly support the view that the adaptation of ocular-opponency-neurons contributes to the ocular dominance plasticity induced by prolonged eye-based attention.

关键词： Attention Ocular dominance Opponency neuron Adaptation Steady-state visually evoked potential