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A Residual Frequency Offset Estimation Method Based on Range Migration Fitting

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Journal of Beijing Institute of Technology 2024年第2期33卷 103-110页

作者： Liting Zhang Hao Huan Ran Tao Xiaogang tang School of Information and Electronics Beijing Institute of Technology School of Aerospace Information Space Engineering University

Recently, researchers have proposed an emitter localization method based on passive synthetic aperture. However, the unknown residual frequency offset(RFO) between the transmitter and the receiver causes the received Doppler signal to shift, which affects the localization accuracy. To solve this issue, this paper proposes a RFO estimation method based on range migration fitting. Due to the high frequency modulation slope of the linear frequency modulation(LFM)-modulation radar signal, it is not affected by RFO in range compression. Therefore, the azimuth time can be estimated by fitting the peak value position of the pulse compression in range ***, the matched filters are designed under different RFOs. When the zero-Doppler time obtained by the matched filters is consistent with the estimated azimuth time, the given RFO is the real RFO between the transceivers. The simulation results show that the estimation error of azimuth distance does not exceed 20 m when the received signal duration is not less than 3 s, the pulse repetition frequency(PRF) of the transmitter radar signal is not less than 1 k Hz, the range detection is not larger than 1 000 km, and the signal noise ratio(SNR) is not less than –5 d B.

关键词： range migration fitting (RMF) passive localization residual frequency offset (RFO)

Nuclear dynamical octupole deformation in heavy-ion reactions

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Frontiers of physics 2015年第5期10卷 103-108页

作者： Cheng tang Xin Jin Nan Wang En-Guang Zhao College of Physics Shenzhen University Shenzhen 518060 China State Key Laboratory of Theoretical Physics Institute of Theoretical Physics Chinese Academy of Sciences Beijing 100190 China Center of Theoretical Nuclear Physics National Laboratory of Heavy Ion Accelerator Lanzhou 730000 China School of Physics Peking University Beijing 100871 China

Within the quantum molecular dynamics （QMD） model, the dynamical octupole deformation is studied as a function of the central distance between the projectile and target in the approaching process of heavy-ion fusion reactions. The dependence of the maximum dynamical octupole defor- mations on tile incident energies is also investigated. The dynamical octupole deformations can be observed during the approaching process, and the maximum dynamical octupole deformations be- come more significant with decreasing incident energies. The distributions of the proton and neutron centers in the projectile and target are also investigated, respectively. In the approaching process of heavy-ion fusion reactions, the separation between proton centers for two nuclei is larger than that between neutron centers because of the strong Coulomb potential.

关键词： heavy-ion reactions nuclear deformation quantum molecular dynamics model

Particular properties of Ti_2O and TiN_x nanoparticles prepared by thermal decomposition

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Rare Metals 2008年第6期27卷 598-602页

作者： LI Xiongping WU Jieda WEN ming tang Xiao LIU Yongqiang Department of Chemistry Tongji University Shanghai 200092 China

Particular properties of Ti2O and TiNx prepared by thermal decomposition were introduced. A precursor prepared by titanium powder reacting with oxalate acid was thermally decomposed in nitrogen atmosphere at 840℃ for 15 min, and relatively pure Ti2O was then obtained. Conductive TiNx was also prepared after altering reaction conditions. Samples were characterized by resistivity, X-ray powder diffraction, transmission electron microscope, Ultraviolet-Visible diffuse reflection, and electromagnetic shielding efficiency. The results indicate that both Ti2O and TiNx have good conductivity. Moreover, Ti2O shows a better solar photocatalytic activity and TiNx does well in the electromagnetic shield.

关键词： inorganic nonmetal materials photocatalytic activity shielding efficiency titanium oxide titanium nitride

Novel photocatalytic reactor for degradation of DDT in water and its optimization model

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第5期10卷 732-738页

作者： Wei-hai PANG Nai-yun GAO Yang DENG Yu-lin tang State Key Laboratory of Pollution Control and Resources Reuse Tongji University Shanghai 200092 China Department of Civil Engineering and Surveying University of Puerto Rico at Mayaguez Mayaguez PR 00681 USA

A novel photocatalytic reactor was developed to remove （1,1-bis（4-chlorophenyl）-2,2,2-trichloroethane）（DDT） from water. In the reactor, a cenosphere was used to support TiO2 film made by means of sol-gel. Because the cenospheres were coated with TiO2, their specific gravity was slightly increased from the original 0.6-0.8 to 0.8-0.9, so that they were able to be suspended in water. With the mixed operation of a bubbler, the water in the reactor was in a well-fluidized state. The bottom of the reactor is a sand filter bed, which can be used to prevent the photocatalyst from being lost. A mathematical model of the reactor has been developed in the two primary influential factors： ultraviolet （UV） light intensity and photocatalyst concentration. With such a model, the reactor can be designed more reasonably.

关键词： Photocatalytic reactor Persistent organic pollutants (POPs) Reactor model

“后革命”时期国家治理：基于承认政治的理论视角

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同济大学学报（社会科学版） 2010年第6期21卷 94-100页

作者：唐慧玲南京大学政府管理学院南京210093

作为一种历史叙事,"后革命"主要指的是社会历史发展的一个新时期,阶级矛盾和阶级斗争已不是社会发展的主要矛盾和主要动力,大量超阶级、跨民族的个人和全人类问题成为社会生活领域的主体,个体与共同体之间的相互承认关系成为这一时期国... 详细信息

作为一种历史叙事,"后革命"主要指的是社会历史发展的一个新时期,阶级矛盾和阶级斗争已不是社会发展的主要矛盾和主要动力,大量超阶级、跨民族的个人和全人类问题成为社会生活领域的主体,个体与共同体之间的相互承认关系成为这一时期国家治理的重要基础。基于承认政治的理论视角,"后革命"时期的国家治理应建立主体间的相互承认范式,依托基于承认基础上的现代民主,深化基于承认基础上的现代政治认同,构建并维护多元的价值体系。

关键词： “后革命” 相互承认承认的政治

^(18)F-FDG PET/CT在诊断浸润性乳腺癌和淋巴结转移中的价值

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上海交通大学学报（医学版） 2012年第6期32卷 761-765页

作者：唐立岷马超青岛大学医学院附属医院核医学科青岛266003 上海交通大学医学院附属新华医院核医学科上海200092

目的评估氟-18标记的2-氟-2-脱氧-D-葡萄糖正电子发射断层扫描(18F-FDG PET/CT)在诊断乳腺癌和腋窝淋巴结(ALN)转移中的价值。方法回顾性分析88例浸润性乳腺癌患者病例资料,所有患者均行18F-FDG PET/CT、钼靶X线和超声检查,40例患者行... 详细信息

目的评估氟-18标记的2-氟-2-脱氧-D-葡萄糖正电子发射断层扫描(18F-FDG PET/CT)在诊断乳腺癌和腋窝淋巴结(ALN)转移中的价值。方法回顾性分析88例浸润性乳腺癌患者病例资料,所有患者均行18F-FDG PET/CT、钼靶X线和超声检查,40例患者行磁共振成像(MRI)检查,将诊断结果与术后病理结果进行比较。结果 88例病理学检查证实浸润性乳腺癌患者中18F-FDG PET/CT检查阳性75例(85%),阴性13例(15%)。18F-FDG PET/CT、钼靶X线、超声检查、钼靶X线结合超声检查和MRI诊断敏感度分别为85%(75/88)、85%(75/88)、92%(81/88)、97%(85/88)和95%(38/40)。与钼靶X线、超声检查和MRI比较,18F-FDG PET/CT诊断原发性乳腺癌的敏感度差异无统计学意义(P>0.05),钼靶X线检查结合超声的敏感度高于18F-FDG PET/CT(P<0.05)。18F-FDG PET/CT诊断原发性乳腺癌的敏感度与肿瘤分期和大小相关(P<0.05)。以最大标准摄取值(SUVmax)1.5为阳性判断标准,18F-FDG PET/CT诊断乳腺癌ALN转移的敏感度、特异度、准确度、阳性预测值和阴性预测值分别为34.1%(8/21)、84%(56/67)、72%(64/88)、42%(8/19)和81%(56/69),假阴性和假阳性率分别为19%(13/69)和57%(11/19)。结论 18F-FDG PET/CT诊断乳腺癌敏感度并不优于钼靶X线、超声和MRI检查,在乳腺癌ALN转移诊断中的价值有限。钼靶X线结合超声检查敏感度高,是诊断乳腺癌的首选方法。

关键词：乳腺癌 18F-FDG PET/CT 钼靶X线检查超声检查腋窝淋巴结

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最少部件数的并联备份问题

电子科技大学学报 2005年第6期34卷 846-849页

作者：唐应辉喻国建刘燕电子科技大学应用数学学院成都610054

如何快速提高系统的可靠度和最少部件数的并联备份问题,一直是系统可靠性问题中的研究热点。该文从系统的任意状态(k1,k2,L,kn)出发,讨论了上述问题,并证明了在子系统可靠度最小的位置上并联相同部件可使系统的可靠度提高最快,同时给出... 详细信息

如何快速提高系统的可靠度和最少部件数的并联备份问题,一直是系统可靠性问题中的研究热点。该文从系统的任意状态(k1,k2,L,kn)出发,讨论了上述问题,并证明了在子系统可靠度最小的位置上并联相同部件可使系统的可靠度提高最快,同时给出了最优算法和实例验证。

关键词：系统可靠度部件状态并联

Bond, vibration and microwave dielectric characteristics of Zn_(1- x)(Li_(0.5)Bi_(0.5))_(x)WO_(4) ceramics with low temperature sintering

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Journal of Materiomics 2022年第2期8卷 392-400页

作者： Qin Zhang Hua Su Huaiwu Zhang Xiaoli tang State Key Laboratory of Electronic Thin Films and Integrated Devices University of Electronic Science and Technology of ChinaChengdu610054China Yangtze River Delta Research Institute of UESTC(Huzhou) Huzhou313000China

The bond,vibration and microwave dielectric characteristics of Zn_(1- x)(Li_(0.5)Bi_(0.5))_(x)WO_(4)(x=0-0.12)ce-ramics were investigated by XRD refinement,Raman and FT-IR spectroscopy and complex bond valence *** results showed that proper substitution of(Li_(0.5)Bi_(0.5))2þcan improve the sintering charac-teristics and microwave dielectric properties of ZnWO_(4).The increase of Q×f value was mainly attributed to dense and uniform microstructure,and the subsequent decrease resulted from the deterioration of structural stability and relative *** to the complex bond valence theory,the chemical bond characteristics of ZnWO_(4) and Bi_(2)WO_(6) played an important role in the dielectric properties of the ***,the samples(x=0.02)sintered at 900℃ showed satisfactory properties:ε_(r)=15.332,Q×f=35,762 GHz,and t_(f)=-65 ppm/℃,making it a potential candidate material for LTCC applications.

关键词： Zn_(1-x)(Li_(0.5)Bi_(0.5))_(x)WO_(4) Complex bond valence theory Raman and FT-IR spectroscopy Microwave dielectric properties

Peptide-based enteral formula improves tolerance and clinical outcomes in abdominal surgery patients relative to a whole protein enteral formula

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World Journal of Gastrointestinal Surgery 2016年第10期8卷 700-705页

作者： ming-Yi Liu Hsiu-Chih tang Shu-hui Hu Sue-Joan Chang Department of Nutrition Tainan Sin-Lau Hospital Department of Life Sciences College of Bioscience and BiotechnologyNational Cheng Kung University Department of Surgery Tainan Sin-Lau Hospital Department of Medical Laboratory Science and Biotechnology Kaohsiung Medical University Department of Nutrition and Dietetics Kaohsiung Medical University Hospital

AIM To compare a dipeptide- and tripeptide-based enteral formula with a standard enteral formula for tolerance and nutritional outcomes in abdominal surgery *** A retrospective study was performed to assess the differences between a whole-protein formula(WPF) and a dipeptide- and tripeptide-based formula(PEF) in clinical ***-two adult intensive care unit(ICU) patients with serum albumin concentrations less than 3.0 g/d L were enrolled in this *** were divided into two groups(WPF group = 40 patients,PEF group = 32 patients).The study patients were fed for at least 7 d,with ≥ 1000 m L of enteral formula infused on at least 3 of the *** The mean serum albumin level on postoperative day(POD) 10,prealbumin levels on POD-5 and POD-10,and total lymphocyte count on POD-5 were significantly higher in the PEF group compared to those in the WPF group(P < 0.05).The average maximum gastric residual volume of the PEF patients during their ICU stays was significantly lower than that for WPF *** Dipeptide- and tripeptide-based enteral formulas are more efficacious and better tolerated than wholeprotein formulas.

关键词： Dipeptides and tripeptides Enteral nutrition Abdominal surgery Gastric residual volume Absorption