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Target location with signal fitting and sub-aperture tracking for airborne multi-channel radar

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Journal of Systems Engineering and Electronics 2010年第5期21卷 752-758页

作者： Zhiwei Yang Guisheng Liao shun he Cao Zeng National Laboratory of Radar Signal Processing Xidian University Xi'an 710071 E R. China Communication and Information Engineering College Xi'an University of Science and Technology Xi'an 710054 E R. China

The location of a moving target based on signal fitting and sub-aperture tracking from an airborne multi-channel radar is dealt *** proposed approach is applied in two steps：first,the ambiguous slant-range velocity is derived with a modified single-snapshot multiple direction of arrival estimation method,and second,the unambiguous slant-range velocity is found using a track-based *** prominent advantage of the proposed approach is that the unambiguous slant-range velocity can be very ***,the first stage is carried out at the determinate range-Doppler test cell by azimuth searching for fitting best to the moving target signal,therefore,the location performance would not be sacrificed in order to suppress clutter and/or *** effectiveness and efficiency of the proposed method are validated with a set of airborne experimental data.

关键词： space-time adaptive processing(STAP) along track interferometry(ATI) ground moving target indication(GMTI).

Oscillation quenching and physical explanation on freeplay-based aeroelastic airfoil in transonic viscous flow

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Chinese Journal of Aeronautics 2023年第10期36卷 124-136页

作者： Yayun SHI shun he Gaowei CUI Gang CheN Yan LIU State Key Laboratory for Strength and Vibration of Mechanical Structures School of Aerospace EngineeringXi’an Jiaotong UniversityXi’an 710049China School of Aeronautics Northwestern Polytechnical UniversityXi’an 710072China Beijing Institute of Structure and Environment Engineering Beijing 100076China Shenyang Aircraft Design Institute Shenyang 110036China

Limit Cycle Oscillation(LCO)quenching of a supercritical airfoil(NLR 7301)considering freeplay is investigated in transonic viscous *** Fluid Dynamics(CFD)based on Navier-Stokes equations is implemented to calculate transonic aerodynamic forces.A loosely coupled scheme with steady CFD and an efficient graphic method are developed to obtain the aerodynamic *** quenching phenomenon is observed from the nonlinear dynamic aeroelastic response obtained by using time marching *** the airspeed increases,LCO appears then quenches,forming the first LCO *** the quenching region,LCO occurs again and sustains until the divergence of the response,forming the second LCO *** quenching of LCOs was addressed physically based on the aerodynamic preload and the linear flutter ***“island”of stable region is observed in the flutter boundary,*** flutter speed versus the mean Angle of Attack(AoA).The LCO quenches when the aerodynamic preload crosses this stable region with the increasing of *** LCO quenching of this model in transonic flow is essentially induced by destabilizing effect from aerodynamic preload,since the flutter speed is sensitive to AoA due to aerodynamic nonlinearity.

关键词： Freeplay Nonlinear aeroelasticity Supercritical airfoil Transonic flutter Unsteady flow

Gut perforation after orthotopic liver transplantation in adults

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World Journal of Gastroenterology 2007年第14期13卷 2125-2128页

作者： Jun Xiong Shen You Xiao-shun he Organ Transplantation Center 1^st Affiliated Hospital Sun Yat-Sen University Guangzhou 510080 Guangdong Province China

AIM： To describe cases of gut perforation after orthotopic liver transplantation.METHODS： Data were colleted from our center database and medical records. Six of 187 patients （3.2%）who underwent orthotopic liver transplantation from January to December 2005 developed gut *** patients were male with an average age of 46 *** piggyback liver transplantation was performed at the Organ Transplantation Center, First Affiliated Hospital, Sun Yat-Sen ***： Previous operation, steroid therapy, and prolonged portal venous cross clamp time, poor nutritional status and iatrogenic injury were found to be its ecological factors. The patients with gut perforation were found to have fever, increased leukocytes, mild abdominal pain and tenderness. The median portal venous clamp time was 63 min （range 45-72 min）,median cold ischaemia time was 11.3 h （range 7-15 h）.Median intraoperative blood loss was 500 mL （range 100-1200 mL） and median operation time was 8.8 h （range 6-12 h）. None of the six patients developed acute cellular rejection. White cell count was above 18 × 10^9/L in five patients （neutrophilic leukocytes were above 90%） and 1.5 × 10^9/L in one patient. Bacterial culture in drainage liquid revealed enterococci in five patients. Of the 6 patients undergoing orthotopic liver transplantation, 3 survived and 3 died after modified piggyback liver transplantation.CONCLUSION： Gut perforation occurs after orthotopic liver transplantation in adults. A careful and minimal dissection during OLT, longer retention of the stomach tube, and reducing the portal clamp time and steroid dose should be taken into consideration. If gut perforation is not prevented, then early diagnosis,preferably through detection of enterococci may ensure better survival.

关键词： Orthotopic liver transplantation Gut perforation Enterococcus faecalis

Design of Gamma Spectrum Data Acquisition and Processing System Based on ARM / DSP

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Journal of Harbin Institute of Technology(New Series) 2013年第2期20卷 27-32页

作者： Jian-Feng he Fang Fang Yue-shun he Bin Tang Key Laboratory of Radioactive Geology and Exploration Technology Fundamental Science for National Defense East China Institute of Technology College of Nuclear Technology and Automation Engineering Chengdu University of Technology

Research for detecting or obtaining radionuclide by gamma energy spectrum data acquisition and process system is one of the key issues about intelligent measurement of gamma-ray spectrum. For this reason, a software and hardware implementation schematic design based on ARM ( Advanced RISC Machines) + DSP ( Digital Signal Processor) architecture for gamma energy spectrum data acquisition and processing system is proposed. The paper discusses in detail some key technologies such as communication interface design between microcontroller ARM and digital signal processor DSP,distribution scheduling under multi-task in the ARM-Linux,DSP handling procedures for multi-channel A / D high-speed sample. At the same time,because the traditional Gaussian fitting to determine the boundary of peak is not ideal,it puts forward a weighting factor of Gaussian function least squares fitting realize boundary determined. Finally gamma-spectrum data from sodium iodide NaI( TI) scintillation detector is tested and processed in the new system. The results show that gamma energy spectrum data acquisition and process system is perfect functionality, stable and convergence in unimodal. Compared with data from conventional energy spectrometers,the system can keep better energy resolution in a wide range of pulse pass rate.

关键词： gamma spectrum data acquisition and processing ARM + DSP architecture ARM-Linux energy spectrometers

Development Phases and Mechanisms of Tectonic Fractures in the Longmaxi Formation Shale of the Dingshan Area in Southeast Sichuan Basin, China

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Acta Geologica Sinica(English Edition) 2018年第6期92卷 2351-2366页

作者： FAN Cunhui he shun ZHANG Yu QIN Qirong ZHONG Cheng State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum University State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Chengdu University of Technology School of Geoscience and Technology Southwest Petroleum University

Shale gas has currently attracted much attention during oil and gas exploration and development. Fractures in shale have an important influence on the enrichment and preservation of shale gas. This work studied the developmental period and formation mechanism of tectonic fractures in the Longmaxi Formation shale in the Dingshan area of southeastern Sichuan Basin based on extensive observations of outcrops and cores, rock acoustic emission(Kaiser) experiments, homogenization temperature of fracture fill inclusions, apatite fission track, thermal burial history. The research shows that the fracture types of the Longmaxi Formation include tectonic fractures, diagenetic fractures and horizontal slip fractures. The main types are tectonic high-angle shear and horizontal slip fractures, with small openings, large spacing, low densities, and high degrees of filling. Six dominant directions of the fractures after correction by plane included NWW, nearly SN, NNW, NEE, nearly EW and NW. The analysis of field fracture stage and fracture system of the borehole suggests that the fractures in the Longmaxi Formation could be paired with two sets of plane X-shaped conjugate shear fractures, i.e., profile X-shaped conjugate shear fractures and extension fractures. The combination of qualitative geological analysis and quantitative experimental testing techniques indicates that the tectonic fractures in the Longmaxi Formation have undergone three periods of tectonic movement, namely mid-late Yanshanian movement(82–71.1 Ma), late Yanshanian and middle Himalaya movements(71.1–22.3 Ma), and the late Himalayan movement(22.3–0 Ma). The middle-late period of the Yanshanian movement and end of the Yanshanian movement-middle period of the Himalayan movement were the main fractureforming periods. The fractures were mostly filled with minerals, such as calcite and siliceous. The homogenization temperature of fracture fill inclusions was high, and the paleo-stress value was large; the tectonic

关键词： shale fracture characteristics formation phases Longmaxi Formation Dingshan area Sichuan Basin

Geological Factors Controlling the Accumulation and High Yield of Marine-Facies Shale Gas: Case Study of the Wufeng-Longmaxi Formation in the Dingshan Area of Southeast Sichuan, China

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Acta Geologica Sinica(English Edition) 2019年第3期93卷 536-560页

作者： FAN Cunhui ZHONG Cheng ZHANG Yu QIN Qirong he shun State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum UniversityChengdu 610500China State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Chengdu University of TechnologyChengdu 610059China Collaborative Innovation Center of Shale Gas Resources and Environment Southwest Petroleum UniversityChengdu 610500China School of Geoscience and Technology Southwest Petroleum UniversityChengdu 610500China

The main geological factors controlling the accumulation and yield of marine-facies shale gas reservoirs are the focus of the current shale gas exploration and development *** this study,the Wufeng-Longmaxi Formation in the Dingshan area of southeast Sichuan was *** cores underwent laboratory testing,which included the evaluation of total organic carbon(TOC),vitrinite reflectance(Ro),whole-rock X-ray diffraction(XRD),pore permeability,and imaging through field emission scanning electron microscopy(FE-SEM).Based on the results of natural gamma ray spectrum logging,conventional logging,imaging logging,and seismic coherence properties,the exploration and development potential of shale gas in the Dingshan area have been discussed *** results showed that(1)layer No.4(WF2-LM4)of the Wufeng-Longmaxi Formation has a Th/U ratiohe shale core,indicating sub-high-energy and low-energy marine-facies anoxic reducing environments.(2)The organic matter is mainly I-type kerogen with a small amount of II1-type *** is a good correlation among TOC,Ro,gas content,and brittle minerals;the fracturing property(brittleness)is 57.3%.Organic and inorganic pores are moderately developed.A higher pressure coefficient is correlated with the increase in porosity and the decrease in permeability.(3)The DY1 well of the shale gas reservoir was affected by natural defects and important latestage double destructive effects,and it is poorly *** DY2 well is located far from the Qiyueshan *** faults are absent,and upward fractures in the Longmaxi Formation are poorly *** well is affected by low tectonic deformation intensity,and it is well preserved.(4)The Dingshan area is located at the junction of the two sedimentary centers of Jiaoshiba and *** thickness of the high-quality shale interval(WF2-LM4)is relatively small,which may be an impo

关键词： main controlling factors enrichment conservation shale gas Dingshan area

cnfishbase:A cyber Chinese fish database

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Zoological Research 2023年第5期44卷 950-953页

作者： Yong-Rui Lu Cheng-Chi Fang shun-Ping he State Key Laboratory of Freshwater Ecology and Biotechnology Institute of HydrobiologyChinese Academy of SciencesWuhanHubei 430072China University of Chinese Academy of Sciences Beijing 100049China Center for Excellence in Animal Evolution and Genetics Chinese Academy of SciencesKunmingYunnan 650223China

Fish constitute the largest group among vertebrates,accounting for more than half of all vertebrate species(Nelson et al.,2016),with new fish described each *** the first edition of Fishes of the World,Nelson(1976)recorded 18818 fish species from 450 families,which increased to 21723 fish species from 445 families in the second edition(Nelson,1984),24618 fish species from 482 families in the third edition(Nelson,1994).

关键词： fish Nelson

Effect of Waxy Wheat Flour Blends on the Quality of Chinese Steamed Bread

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Agricultural Sciences in China 2007年第10期6卷 1275-1282页

作者： QIN Peng CheNG shun-he MA Chuan-xi Lixiahe Region Agricultural Research Institute of Jiangsu Province Yangzhou 225007 P.R.China Agronomy College Anhui Agricultural University Hefei 230036 P.R.China Agronomy College Yunnan Agricultural University Kunming 650201 P.R.China

Steamed bread is very popular in the East and Southeast Asian regions, and its quality is affected by some physicochemical properties. Chinese steamed bread was made by adding waxy flour into normal wheat flour in the present study. The results showed that specific volume was not affected by the proportions of waxy flour, whereas, adding waxy flour decreased the appearance, color, texture, elasticity, stickiness, and the total score of Chinese steamed bread. However, there were no significant differences in all values when the proportions of waxy flour were below 10%. All evaluations but specific volume of Chinese steamed bread were positively influenced by the peak viscosity, resistance, and maximum resistance. When the waxy flour proportions were below 25%, the firmness of Chinese steamed bread stored at -18℃ for 3 days gradually decreased with the increase of waxy flour. It was revealed that the qualities of Chinese steamed bread cannot be improved by waxy flour but it can be widely used in frozen storing food in the future.

关键词： waxy wheat Chinese steamed bread quality

Research on Comparison and Evaluation Studies of Several Smoothing Denoising Method Based on γ-ray Spectrum Detector

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Journal of Harbin Institute of Technology(New Series) 2013年第2期20卷 7-11页

作者： Jian-Feng he Fang Fang Yao-Zong Yang Yue-shun he Bin Tang College of Nuclear Technology and Automation Engineering Chengdu University of Technology Key Laboratory of Radioactive Geology and Exploration Technology Fundamental Science for National Defense East China Institute of Technology

The extraction of spectral parameters is very difficult because of the limited energy resolution for NaI （TI） gamma-ray detectors. For statistical fluctuation of radioactivity under complex environment, some smoothing filtering methods are proposed to solve the problem. These methods include adopting method of arithmetic moving average, center of gravity, least squares of polynomial, slide converter of discrete funcion convolution etc. The process of spectrum data is realized, and the results are assessed in H/FWHM（ Peak High/Full Width at Half Maximum） and peak area based on the Matlab programming. The results indicate that different methods smoothed spectrum have respective superiority in different ergoregion, but the Gaussian function theory in discrete function convolution slide method is used to filter the complex y-spectrum on Embedded system nlatform, and the statistical fluctuation of y-snectrum filtered wall.

关键词： T-spectrum data-processing smoothing denoising method comparison and evaluation matlabprogramming