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一种超宽带(UWB)正交成形脉冲设计方法

铁道学报 2010年第4期32卷 125-129页

作者：张敏朱刚王九九烟翔北京交通大学电子信息工程学院北京100044

超宽带(UWB)扩频通信是一种当前短距离无线连接中的关键技术,而成形脉冲设计是关系到UWB系统性能的关键因素,也是当前的研究热点。本文基于压缩Chirp脉冲和Hermite矩阵特征向量,提出一种新的超宽带正交成形脉冲设计方法。首先利用压缩Ch... 详细信息

超宽带(UWB)扩频通信是一种当前短距离无线连接中的关键技术,而成形脉冲设计是关系到UWB系统性能的关键因素,也是当前的研究热点。本文基于压缩Chirp脉冲和Hermite矩阵特征向量,提出一种新的超宽带正交成形脉冲设计方法。首先利用压缩Chirp脉冲产生UWB的脉冲波形;然后构造Hermite矩阵,根据其特征向量对UWB成形脉冲进行正交化,用于支持多用户系统。仿真结果表明,利用该方法产生的UWB正交成形脉冲,能更好地满足UWB标准中频谱模板的要求,具有优良的频谱利用率和较好的自相关与互相关特性。同时,依据该方法设计脉冲具有较大灵活性,能够有效抑制与无线局域网(WLAN IEEE802.11a)的同频干扰。

关键词：超宽带成形脉冲功率谱密度线性调频

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中国组织工程研究与临床康复 2007年第34期11卷 6908-6911页

作者： Jin xiang-chun Fang Jin-nü Huang Ming-ai Jin Zhong-jiu Jin Ping-xi Medical Division Yanbian UniversityYanji 133000 JilinProvince China Yanji CommunityMedical Office of JilinProvince Yanji133000 JUin ProvinceChina Antu CountyHospital Antu133600 JUin ProvinceChina

Background: The prevalence of obesity and the related factors may be different among different nationalities, and different types of obesity have different influence on cerebrovascular and cardiovascular diseases. Objective: To investigate the characteristics and related factors of obesity in Korean and Han populations in rural Yanbian. Design: A randomized controlled observation. Setting: Antu County Hospital of Jilin Province. Participants: The survey was carried out in 4 towns of Tumen city and Antu county in Yanbian area from August 2004 to August 2005. Totally 1 786 Korean and Han residents above 30 years old were randomly selected, the proportion of nationalities in each area was close. In order to accurately compare the prevalence of obesity among different nationalities, family members of mixed blood were excluded, as well as patients with severe cardiovascular disease and other organic diseases. Informed contents were obtained from all the subjects. Methods: The information related to this survey was collected by means of home visit and physical examination in the selected community and health center. All the investigators were strictly trained to standardize the contents, procedure and methods before the survey. Related information was collected by means of face-to-face inquisition with uniform questionnaire. 2 All the examinees accepted the physical examination in the morning under fasting and resting states by uniform device and examiners. The physical examination included measurements of body height, body mass, waistline, hip circumference, blood pressure. Fasting venous blood (2 mL) was collected to determine serum levels of total cholesterol, triglyceride, high density lipoprotein-cholesterol (HDL-C) and fasting plasma glucose with automatic biochemical analyzer. 3 The crude prevalence rate was calculated. The age adjusted prevalence rate was calculated directly by using the sample survey data of Yanbian Korean National Minority Autonomous Prefecture

关键词：肥胖症混合血液不同国家高血压高血糖症

Therapeutic effects of globular adiponectin in diabetic rats with nonalcoholic fatty liver disease

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World Journal of Gastroenterology 2014年第40期20卷 14950-14957页

作者： Hong Ma Fan Cui Jing-Jing Dong Guo-Ping You xiang-jiu Yang Hua-Dong Lu Yan-Ling Huang Department of Endocrinology Zhongshan Hospital Xiamen University Department of Endocrinology Xiamen Zhongshan Teaching Hospital of Fujian Medical University Department of Pathology Zhongshan Hospital Xiamen University

AIM: To explore the therapeutic role of globular adiponectin (gAd) in high-fat diet/streptozotocin (STZ)-induced type 2 diabetic rats with nonalcoholic fatty liver disease (NAFLD).

关键词： Adiponectin Insulin secretion Insulin receptor Steatosis

STUDY ON LOW Ni CATALYST FOR METHANATION OF TOWN GAS

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Journal of Energy Chemistry 1993年第2期 119-128页

作者： wang Da-xiang JIANG Fu-Hong KANG Xi-Hui ZHAO jiu-Sheng Department of Chemical Engineering Tianjin University,Tianjin 300072

On the basis of the characterization of typical catalysts by activityevaluation,TPR,XRD and TEM,the effects of nickel content and promoterssuch as MgO,La2O3,and MnO2were *** of MgNiO2by thecombination of promoter MgO with NiO increases the catalyst ***-er La2O3is found well-distributed on the catalyst surface in the form of La2O3without any interaction with uther *** physically scattering ef-fect,La2O3can prohibit active component Ni from sintreing at high temperatureand then improve its thermal *** also affects the catalyst activity *** of La2O3decreases the content of small Ni crystallite,and is helpful to the prohibition of carbon deposition.A new Ni-based town gasmethanation catalyst of low Ni content with high activity and high carbon depo-sition resistance is successfully developed in the laboratory.

关键词： Ni high

Fluorescent graphene oxide derived from carbonized citric acid for copper(Ⅱ) ions detection

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Rare Metals 2021年第6期40卷 1443-1450页

作者： Wen-Dan Li xiang-Yu Zeng Gang-Yu Lv Zhen-Hui Liang Qi-Jie Liu Wan-Qi Fu jiu-An Zhang Yan-Xian Feng Hao-Yi Wu School of Physics and Optoelectronic Engineering Guangdong University of TechnologyHEMCGuangzhou 510006China School of Biotechnology and Health Science Wuyi UniversityJiangmen 529020China

Fluorescent graphene oxide(GO) nanoparticles were obtained from the thermal carbonization of citrate *** on the synthesizing temperature,the size of GO varied from several to several hundred *** to the confinement from the size,green and blue emissions at around 504 and 450 nm were observed from the GO *** emissions could be dynamically quenched by titrating against copper(Ⅱ)(Cu^(2+)) ions,and the emission intensity was reduced exponentially as a function of Cu^(2+)*** quenching mechanism was ascribed to the bridging of the surface-COOH andOH groups by Cu^(2+),which restricted the vibration of edge atoms or clusters and reduced the number of luminophores of GO *** a result,the concentration of Cu^(2+)was detectable with the fluorescent intensity of GO.

关键词： Graphene oxide Fluorescence Copper(Ⅱ)detection

Baicalin Induces IFN-α/β and IFN-γ Expressions in Cultured Mouse Pulmonary Microvascular Endothelial Cells

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Journal of Integrative Agriculture 2012年第4期11卷 646-654页

作者： HU Ge XUE jiu-zhou LIU Jing ZHANG Tao DONG Hong DUAN Hui-qin YANG Zuo-jun REN Xiao-ming MU xiang Animal Science and Technology College Beijing University of Agriculture Beijing 102206 P.R.China Beijing Key Laboratory of Traditional Chinese Veterinary Medicine Beijing University of Agriculture Beijing 102206 P.R.China

We studied the effect of baicalin,an extract from Radix Scutellariae（a traditional Chinese medicine） in inducing mouse pulmonary microvascular endothelial cells（MPMVECs） to produce interferons（IFNs）.MPMVECs were cultured in vitro in the presence of different concentrations of baicalin（10,20,and 30 μg mL-1）,and the cells and the culture media were harvested at various time *** proteins and mRNA levels（relative to β-actin） of IFN-α/β and IFN-γ were analyzed by RT-PCR and enzyme-linked immunosorbent assay（ELISA）.It was observed that baicalin substantially up-regulated the expression of IFN-α/β and IFN-γ.In all baicalin-treated groups,the relative levels of IFN-α/β and IFN-γ mRNAs peaked after 12 h of culturing,and IFN-α/β and IFN-γ proteins peaked after 24 h of *** results suggest that baicalin can effectively induce the expression of IFNs in pulmonary microvascular endothelial cells,and thus potentially act as an antiviral *** study may provide background information for developing new antiviral drugs based on baicalin.

关键词： baicalin pulmonary microvascular endothelial cells interferon mouse

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一种混沌映射的相空间去噪方法

物理学报 2013年第23期62卷 52-59页

作者：吕善翔冯久超华南理工大学电子与信息学院广州510641

对于混沌映射来说,它们的频谱比混沌流的频谱更广阔,与噪声频谱的重叠率更高,所以混沌流的去噪方法对它们并不适用.在半盲分析法的框架下,混沌系统的参数估计问题终将归结为最小二乘估计问题.本文从最小二乘拟合的角度出发估计混沌映射... 详细信息

对于混沌映射来说,它们的频谱比混沌流的频谱更广阔,与噪声频谱的重叠率更高,所以混沌流的去噪方法对它们并不适用.在半盲分析法的框架下,混沌系统的参数估计问题终将归结为最小二乘估计问题.本文从最小二乘拟合的角度出发估计混沌映射的演化参数,进而通过相空间重构以及投影操作,实现对观测信号的噪声抑制.实验结果表明,该算法的去噪效果优于扩展卡尔曼滤波器(extended Kalman filter,EKF)和无先导卡尔曼滤波器(unscneted Kalman filter,UKF),并且能够较大程度地将信号源的混沌特征量还原.

关键词：混沌噪声抑制相空间重构投影

超声内镜与传统影像学在胆总管扩张病变中的诊断价值比较

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临床消化病杂志 2024年第4期36卷 256-260页

作者：陶莉胡祥鹏谢菁徐帆方倩倩章礼久刘珺安徽医科大学第二附属医院消化内科安徽合肥230601 安徽医科大学病理生理教研安徽合肥230032

[目的]评价超声内镜(EUS)和传统影像学检查在不明原因胆总管(CBD)扩张病因诊断中的价值。[方法]对78例不明原因CBD扩张患者的实验室检查、传统影像学及EUS结果进行回顾性分析,以活检、穿刺、手术病理及至少12个月的随访结果作为最终诊断... 详细信息

[目的]评价超声内镜(EUS)和传统影像学检查在不明原因胆总管(CBD)扩张病因诊断中的价值。[方法]对78例不明原因CBD扩张患者的实验室检查、传统影像学及EUS结果进行回顾性分析,以活检、穿刺、手术病理及至少12个月的随访结果作为最终诊断。[结果]78例CBD扩张患者中,肿瘤患者(恶性组)与结石及炎性患者(良性组)的性别、发病年龄比较差异无统计学意义。恶性组患者黄疸、体质量下降和胰管扩张多于良性组,而良性组患者腹痛、腹胀更为多见。EUS对CBD扩张病变诊断的灵敏度(97.1%)显著优于经腹超声(US,50%)、CT(70%)和MRI(50%)等常规影像学检查方法。EUS对CBD扩张病变的诊断特异性(86.0%)略优于US(57.1%)和CT(77.1%)。EUS对CBD扩张病变的诊断准确度(91.0%)显著优于US(54.5%)、CT(73.8%)和MRI(74.5%)。EUS对CBD扩张病变的诊断阴性预测值(97.4%)显著优于US(40.0%)、CT(75.0%)和MRI(73.7%)。[结论]EUS在CBD扩张病变中的诊断灵敏度、准确性和阴性预测值显著优于US、CT及MRI等传统影像学检查,特异度略优于US和CT。对传统影像学诊断不明的CBD扩张患者,进一步选用EUS检查明确病因是合理的。

关键词：胆总管扩张超声内镜传统影像学诊断

Modelling Immune System:Principles,Models,Analysis and Perspectives

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Journal of Bionic Engineering 2009年第1期6卷 77-85页

作者： xiang-hua Li~1, Zheng-xuan wang~1, Tian-yang Lu~2, xiang-jiu Che~11. College of Computer Science and Technology, Jilin University, Changchun 130012, P. R. China2. College of Computer Science and Technology, Harbin Engineering University, Harbin 150001, P. R. China College of Computer Science and Technology Jilin University Changchun P. R. China College of Computer Science and Technology Harbin Engineering University Harbin P. R. China

The biological immune system is a complex adaptive *** are lots of benefits for building the model of the immune *** biological researchers,they can test some hypotheses about the infection process or simulate the responses of some *** computer researchers,they can build distributed,robust and fault tolerant networks inspired by the functions of the immune *** paper provides a comprehensive survey of the literatures on modelling the immune *** the methodology perspective,the paper compares and analyzes the existing approaches and models,and also demonstrates the focusing research effort on the future immune models in the next few years.

关键词： immune system modelling agent-based simulation complex adaptive system (CAS) HIV