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稀有衰变B^0(B_s)→γν(ν|ˉ)分支比的计算

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高能物理与核物理 2006年第4期30卷 289-293页

作者：陈军肖侯召宇李营吕才典中国科学院高能物理研究所石家庄铁道学院数学物理系石家庄050043

在标准模型中,三体稀有衰变B0(Bs)→γνν-只有通过箱图和企鹅图才可以发生．这个过程对于确定B介子的衰变常数及其波函数有着较重要的物理意义,由于这些衰变道的分支比较小,因此也是探测新物理理论的比较好的场所．利用B介子强衰变确... 详细信息

在标准模型中,三体稀有衰变B0(Bs)→γνν-只有通过箱图和企鹅图才可以发生．这个过程对于确定B介子的衰变常数及其波函数有着较重要的物理意义,由于这些衰变道的分支比较小,因此也是探测新物理理论的比较好的场所．利用B介子强衰变确定的波函数,得到B0(Bs)→γνν-的分支比的数量级是10-9(10-8),这些结果可以在未来的实验上得到检验．

关键词：波函数 B介子稀有衰变分支比衰变常量

局部相关加权中值滤波技术及其在叠后随机噪声衰减中的应用

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地球物理学报 2011年第2期54卷 358-367页

作者：刘洋王典刘财冯晅吉林大学地球探测科学与技术学院长春130026 美国德州大学奥斯汀分校奥斯汀78713

随机噪声的衰减和同相轴连续性的提高可以极大地改善地震资料解释的精度.本文提出一种新的滤波技术,既能够有效地衰减随机噪声义可以很好地保护地震资料中的断层等信息不被破坏,增强地震剖面中弯曲、倾斜同相轴的连续性.该方法结合新的... 详细信息

随机噪声的衰减和同相轴连续性的提高可以极大地改善地震资料解释的精度.本文提出一种新的滤波技术,既能够有效地衰减随机噪声义可以很好地保护地震资料中的断层等信息不被破坏,增强地震剖面中弯曲、倾斜同相轴的连续性.该方法结合新的加权中值滤波技术和两种构造信息保护滤波策略,实现基于预测数据体和基于倾角走向的加权中值滤波.通过设计局部相关系数改进加权中值滤波器的特性,达到保护断层信息的效果.使用地震数据的局部倾角属性设计预测构造数据体和构造走向,进而构建两种滤波策略,通过匹配加权中值滤波器和不同的处理策略,达到保护断层信息和噪声衰减的平衡点.通过对比离散小波变换阈值去噪方法,理论模型和实际数据的处理结果证明了局部相关加权中值滤波技术的有效性.

关键词：加权中值滤波随机噪声构造信息保护局部相关局部地震倾角

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基于最优汇集时间间隔的城市间断交通流预测

浙江大学学报（工学版） 2023年第8期57卷 1607-1617页

作者：王殿海谢瑞蔡正义浙江大学智能交通研究所浙江杭州310058

针对城市交通流受信号控制的影响而呈现出间断性、周期性和随机性的特点,提出基于最优汇集时间间隔的城市间断交流预测方法.该方法首先基于傅里叶变换和自相关分析获取城市间断交通流的信号控制周期,再利用交叉验证均方差模型确定最优... 详细信息

针对城市交通流受信号控制的影响而呈现出间断性、周期性和随机性的特点,提出基于最优汇集时间间隔的城市间断交流预测方法.该方法首先基于傅里叶变换和自相关分析获取城市间断交通流的信号控制周期,再利用交叉验证均方差模型确定最优汇集时间间隔与信号周期的关系,在此基础上提出融合贝叶斯神经网络和深度学习模型的lSTM-BConv预测模型.基于实测数据的实验结果表明:1)基于最优汇集时间间隔统计交通流数据能有效提升城市间断交通流预测模型的预测精度;2)城市间断交通流数据的最优汇集时间间隔为交通信号控制周期的倍数;3)对比试验结果表明,lSTM-BConv预测模型优于常见的预测模型,平均绝对百分比误差提升了4.57%.预测结果可以为信号控制方案的优化提供参考依据.

关键词：城市间断流最优汇集时间间隔信号控制周期短时交通流预测贝叶斯卷积神经网络

Inhibiting Effects of Achyranthes Bidentata Polysaccharide and lycium Barbarum Polysaccharide on Nonenzyme Glycation in D-galactose Induced Mouse Aging Model

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Biomedical and Environmental Sciences 2003年第3期16卷 267-275页

作者： HONG-BIN DENG, DA-PENG CUI, JIAN-MING JIANG, YAN-CHUN FENG,NIAN-SHENG cai, AND dian-DONG lIInstitute of Medicinal Biotechnology, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China Institute of Medicinal Biotechnology Chinese Academy of Medical Sciences and Peking Union Medical College 北京 100050

Objective To investigate the inhibiting effects and mechanism of achyranthes bidentata polysaccharide (ABP) and lycium barbarum polysaccharide (lBP) on nonenzyme glycation in D-galactose induced mouse aging model. Methods Serum AGE levels were determined by AGE-ElISA, MTT method was used to determine lymphocyte proliferation, Il-2 activity was determined by a bioassay method. Spontaneous motor activity was used to detect mouse's neuromuscular movement, latency of step-through method was used to examine learning and memory abilities of mouse, colormetric assay was used to determine hydroxyproline concentration in mouse skin, pyrogallol autoxidation method was used to determine superoxide dismutase (SOD) activity of erythrocytes. Results Decreased levels of serum AGE, hydroxyproline concentration in mouse skin and spontaneous motor activity in D-galactose mouse aging model were detected after treated with ABP or lBP, while lymphocyte proliferation and Il-2 activity, learning and memory abilities, SOD activity of erythrocytes, were enhanced. Conclusions ABP and lBP could inhibit nonenzyme glycation in D-galactose induced mouse aging model in vivo and ABP has a better inhibiting effect than lBP.

关键词： Achyranthes bidentata polysaccharide(ABP) lycium barbarum polysaccharide(lBP) D-galactose Nonenzyme glycation Aging

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《淮南子》的历史思想

古籍整理研究学刊 2010年第6期 1-3,13页

作者：许殿才北京师范大学历史学院史学研究所

《淮南子》是一部思想丰富的理论著作。此书以史论结合的方式进行理论探索,书中的历史思考,是汉代史学成就的组成部分。《淮南子》认为道是化生宇宙万物的本初形态;人们的社会历史活动应以体道为根本原则;社会历史的变化有着阶段性的特点。

关键词：《淮南子》刘安历史思想

Application of spectral decomposition technology in shallow gas detection based on Wigner-Ville distribution

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Global Geology 2014年第4期17卷 243-246页

作者： CHI Huanzhao lIU cai SHAN Xuanlong WANG dian lU Qi College of Earth Sciences Jilin University College of Geo-Exploration Science and Technology Jilin University

Shallow gas is composed of all kinds of shallow buried natural gas resources( < 1500 m) with relatively small reserve for each gas resource. It has some advantages such as shallow burial depth,good physical properties... 详细信息

Shallow gas is composed of all kinds of shallow buried natural gas resources( latively small reserve for each gas resource. It has some advantages such as shallow burial depth,good physical properties and the huge accumulations. Based on the Wigner-Vill distribution,a general spectral decomposition method is applied in the shallow gas detection. Cone-shaped kernel function filtering method is used to suppress cross-terms of the Wigner-Ville distribution,which is tested on field seismic data. Because of shallow gas reservoir has a characteristic that low frequency energy is stronger and high frequency energy is weaker,it indicates the presence of shallow gas successfully.

关键词： shallow gas Wigner-Ville distribution cross-term interference kernel function spectral decomposi-tion

Cytokines Expression in lymphocytes From Rats With Allergic Asthma Induced by Pleurotus sapidus besidiospores

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Biomedical and Environmental Sciences 1998年第2期11卷 115-124页

作者： CHEN WEI lI dian-DONG PIAO WEN-HUA lANG WEN-FANG AND cai NIAN-SHENG(Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China Institute of Occupational Medicine, Chinese Academy of Pr Institute of Medicinal Biotechnology Chinese Academy of Medical Sciences Peking Union Medical College Beijing 100050 China Department of Oncology Institute of Medicinal Biotechnology Chinese Academy of Medical Sciences Tiantan Beijing 100050 China Institute of Occupational Medicine Chinese Academy of Preventive Medicine Beijing 100050 China

Allergic asthma caused by mushroom spores (Pleurotus sapidus besidiospores) is a common health problem among mushroom-cultivating workers in China. An animal model of allergic asthma through the challenge of Pleurotus sapidus besidiospores in primed rats was developed for investigating the role of cytokines in the pathogenesis of the disease. In the study a series of related cytokines and their receptors, including their activity and mRNA levels of spleen lymphocytes isolated from asthmatic rats, were measured. Determined by 3H-TdR incorporation assay and NAG microcolorimetric assay, Con A-induced spleen lymphocyte proliferation and Il-2 activity in culture supernatants of spleen lymphocytes from 7-day challengedrats with allergic asthma increased significantly by 261% and 208%, respectively, as compared with those in the control. Cytokines and their receptor expression at mRNA levels were determined by RNA/cDNA hybridization, using (α-32P-dCTP radiolabeled cDNA probes for different cytokines and their receptors in vitro. The results showed that mRNA expression of Il-4, GM-CSF, Il-6, Il-2 and Il-2R, except Il-6R, in lymphocytes of 7-day-challenged asthma-suffering rats, increased significantly by 54%, 45%, 170%, 83% and 76%, respectively. In 2-day challenged-rats, mRNA levels of Il-4, Il-6 and Il-2 increased by 37%,58% and 125%, respectively, whereas mRNA leve1s of GM-CSF, Il-2R and Il-6R remained unchanged. Thus, the experimental results suggested a significant increase in TH2type cytokines in the pathogenesis of Pleurotus sapidus besidiospore-induced allergic asthma and Il-4 may play an essential role.

关键词： CSF GM Cytokines Expression in lymphocytes From Rats With Allergic Asthma Induced by Pleurotus sapidus besidiospores

Epitaxial growth and transport properties of compressively-strained Ba_(2)IrO_(4) films

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Chinese Physics B 2021年第8期30卷 492-495页

作者： Yun-Qi Zhao Heng Zhang Xiang-Bin cai Wei Guo dian-Xiang Ji Ting-Ting Zhang Zheng-Bin Gu Jian Zhou Ye Zhu Yue-Feng Nie National laboratory of Solid State Microstructures College of Engineering and Applied Sciencesand Collaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing 210093China Department of Physics The Hong Kong University of Science and TechnologyClear Water BayKowloonHong KongChina Department of Applied Physics Research Institute for Smart EnergyThe Hong Kong Polytechnic UniversityHung HomKowloonHong KongChina

Ba_(2)IrO_(4) is a sister compound of the widely investigated Sr_(2)IrO_(4) and has no IrO_(6) octahedral rotation nor net canted antiferromagnetic moment,thus it acts as a system more similar to the high-T_(c) *** this work,we synthesize the Ba_(2)IrO_(4) epitaxial films by reactive molecular beam epitaxy and study their crystalline structure and transport properties under biaxial compressive *** resolution scanning transmission electron microscopy and x-ray diffraction confirm the high quality of films with partial strain *** compressive epitaxial strain,the Ba_(2)IrO_(4) exhibits the strain-driven enhancement of the conductivity,consistent with the band gap narrowing and the stronger hybridization of Ir-t_(2g) and O-2p orbitals predicted in the first-principles calculations.

关键词： molecular beam epitaxy iridate oxides epitaxial strain transport properties

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星载SAR-GMTI研究进展

国防科技大学学报 2009年第4期31卷 87-92页

作者：梁甸农蔡斌王敏董臻国防科技大学电子科学与工程学院湖南长沙410073 装备指挥技术学院北京101416

星载SAR-GMTI系统具有地面(海面)大面积侦察、监视和运动目标检测、跟踪、定位的能力,是航天侦察的重要手段之一,可以为战场指挥、精确打击、态势评估提供高质量的情报信息。主要讨论星载SAR-GMTI系统及其研究进展,简述了国内外研究、... 详细信息

星载SAR-GMTI系统具有地面(海面)大面积侦察、监视和运动目标检测、跟踪、定位的能力,是航天侦察的重要手段之一,可以为战场指挥、精确打击、态势评估提供高质量的情报信息。主要讨论星载SAR-GMTI系统及其研究进展,简述了国内外研究、发展现状,分析了现有的星载SAR/GMTI系统的优缺点和关键技术,探讨了星载SAR-GMTI系统所面临的技术挑战和研究重点。

关键词：星载SAR系统 SAR-GMTI 关键技术研究重点