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Free-walking:Pedestrian inertial navigation based on dual foot-mounted IMU 被引量:1
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作者 Qu Wang Meixia Fu +6 位作者 Jianquan Wang Lei Sun Rong Huang Xianda Li Zhuqing Jiang Yan Huang Changhui Jiang 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第3期573-587,共15页
The inertial navigation system(INS),which is frequently used in emergency rescue operations and other situations,has the benefits of not relying on infrastructure,high positioning frequency,and strong real-time perfor... The inertial navigation system(INS),which is frequently used in emergency rescue operations and other situations,has the benefits of not relying on infrastructure,high positioning frequency,and strong real-time performance.However,the intricate and unpredictable pedestrian motion patterns lead the INS localization error to significantly diverge with time.This paper aims to enhance the accuracy of zero-velocity interval(ZVI)detection and reduce the heading and altitude drift of foot-mounted INS via deep learning and equation constraint of dual feet.Aiming at the observational noise problem of low-cost inertial sensors,we utilize a denoising autoencoder to automatically eliminate the inherent noise.Aiming at the problem that inaccurate detection of the ZVI detection results in obvious displacement error,we propose a sample-level ZVI detection algorithm based on the U-Net neural network,which effectively solves the problem of mislabeling caused by sliding windows.Aiming at the problem that Zero-Velocity Update(ZUPT)cannot suppress heading and altitude error,we propose a bipedal INS method based on the equation constraint and ellipsoid constraint,which uses foot-to-foot distance as a new observation to correct heading and altitude error.We conduct extensive and well-designed experiments to evaluate the performance of the proposed method.The experimental results indicate that the position error of our proposed method did not exceed 0.83% of the total traveled distance. 展开更多
关键词 Indoor positioning inertial navigation system(INS) Zero-velocity update(ZUPT) Internet of things(IoTs) Location-based service(LBS)
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Suppression of the G-sensitive drift of laser gyro in dual-axis rotational inertial navigation system 被引量:3
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作者 YU Xudong WANG Zichao +2 位作者 FAN Huiying WEI Guo WANG Lin 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2021年第4期822-830,共9页
The dual-axis rotational inertial navigation system(INS)with dithered ring laser gyro(DRLG)is widely used in high precision navigation.The major inertial sensor errors such as drift errors of gyro and accelerometer ca... The dual-axis rotational inertial navigation system(INS)with dithered ring laser gyro(DRLG)is widely used in high precision navigation.The major inertial sensor errors such as drift errors of gyro and accelerometer can be averaged out,but the G-sensitive drifts of laser gyro cannot be averaged out by indexing.A 16-position rotational simulation experiment proves the G-sensitive drift will affect the long-term navigation error for the rotational INS quantitatively.The vibration coupling and asymmetric structure of the DRLG are the main errors.A new dithered mechanism and optimized DRLG is designed.The validity and efficiency of the optimized design are conformed by 1 g sinusoidal vibration experiments.An optimized inertial measurement unit(IMU)is formulated and measured experimentally.Laboratory and vehicle experimental results show that the divergence speed of longitude errors can be effectively slowed down in the optimized IMU.In long term independent navigation,the position accuracy of dual-axis rotational INS is improved close to 50%,and the G-sensitive drifts of laser gyro in the optimized IMU are less than 0.0002°/h.These results have important theoretical significance and practical value for improving the structural dynamic characteristics of DRLG INS,especially the highprecision inertial system. 展开更多
关键词 inertial navigation rotational inertial navigation system(INS) laser gyro G-sensitive drift
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Error Model of Rotary Ring Laser Gyro Inertial Navigation System 被引量:2
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作者 张伦东 练军想 +1 位作者 吴美平 郑志强 《Journal of Beijing Institute of Technology》 EI CAS 2010年第4期439-444,共6页
To improve the precision of inertial navigation system(INS) during long time operation,the rotation modulated technique(RMT) was employed to modulate the errorr of the inertial sensors into periodically varied sig... To improve the precision of inertial navigation system(INS) during long time operation,the rotation modulated technique(RMT) was employed to modulate the errorr of the inertial sensors into periodically varied signals,and,as a result,to suppress the divergence of INS errors.The principle of the RMT was introduced and the error propagating functions were derived from the rotary navigation equation.Effects of the measurement error for the rotation angle of the platform on the system precision were analyzed.The simulation and experimental results show that the precision of INS was ① dramatically improved with the use of the RMT,and ② hardly reduced when the measurement error for the rotation angle was in arc-second level.The study results offer a theoretical basis for engineering design of rotary INS. 展开更多
关键词 inertial navigation system(INS) rotation modulated technique(RMT) error function inertial sensor
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新版MEDL INE光盘著者检索与网上查询比较分析 被引量:1
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作者 陈国琪 《继续医学教育》 2002年第6期48-50,共3页
目的 :评价不同的检索式的检索效果 ,旨在提高著者检索的查全率和查准率。方法 :举例介绍英语人名各种署名形式 ,针对 2 0 0 2年版MEDLINE光盘的著录特点 ,编制相应的检索式及与网上查询效果对比分析。结果 :遇姓名中含有前缀词、后缀... 目的 :评价不同的检索式的检索效果 ,旨在提高著者检索的查全率和查准率。方法 :举例介绍英语人名各种署名形式 ,针对 2 0 0 2年版MEDLINE光盘的著录特点 ,编制相应的检索式及与网上查询效果对比分析。结果 :遇姓名中含有前缀词、后缀词或复姓时 ,MEDLINE光盘和网上检索均可获得较高的查准率 ;而名缩写或截词后以及中、日文音译名检出的文献 ,则误检率高。调整检索式后 ,既保证了查全率 ,又剔除了误检文献。结论 :从而达到迅速而准确地检出所需文献的目的。 展开更多
关键词 作者检索 MEDL ine PUBMED
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地下隧道-土体非线性动力相互作用的FE-IE-INE模型的研究
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作者 邓芃 刘艳 毕继红 《昆明理工大学学报(理工版)》 2005年第3期89-92,99,共5页
在考虑了土与结构的相互作用的基础上,采用FE-IE-INE模型来模拟土体的分层性、非线性以及土体和钢筋混凝土之间的滑移、拉裂、嵌入及土体的半无限边界.阐述了接触元建立的方法;推导了平行无限元的单元刚度矩阵方法以及无限元单元刚度矩... 在考虑了土与结构的相互作用的基础上,采用FE-IE-INE模型来模拟土体的分层性、非线性以及土体和钢筋混凝土之间的滑移、拉裂、嵌入及土体的半无限边界.阐述了接触元建立的方法;推导了平行无限元的单元刚度矩阵方法以及无限元单元刚度矩阵组装成总体刚度矩阵的原理.通过对一双洞口矩形截面隧道的地震反应进行分析,为地下结构的抗震设计提供参考意见. 展开更多
关键词 FE—IE—ine模型 有限元 接触元 无限元 地铁隧道 抗震设计
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低压工作的高速10bit Pipelined ADC
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作者 王为之 《中国集成电路》 2008年第8期27-33,共7页
本文提出了一种低压工作的高速10bit Pipelined ADC。采用自举时钟采样和Cascode频率补偿等方法,该ADC可以在低电压下工作,并达到较高的带宽。该ADC在HJTC 0.18-μmCMOS数模混合工艺下进行了设计仿真和流片测试,结果表明:当供电电压为1.... 本文提出了一种低压工作的高速10bit Pipelined ADC。采用自举时钟采样和Cascode频率补偿等方法,该ADC可以在低电压下工作,并达到较高的带宽。该ADC在HJTC 0.18-μmCMOS数模混合工艺下进行了设计仿真和流片测试,结果表明:当供电电压为1.8V,采样频率为62.5MSample/s时,所设计的ADC对于1MHz的输入信号转换有效位数可以达到52.2dB SFDR、44.8dB SNR和44.3dB SNDR。 展开更多
关键词 Pipel ined ADC 低压 CMOS
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INE原油期货交割执行相关问题及对策研究
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作者 吴穹 《石油石化物资采购》 2019年第33期29-30,共2页
2018年3月26日,上海原油期货在上海期货交易所子公司上海国际能源交易中心(INE)正式上市交易,开启了中国期货市场国际化的新篇章。本文研究了INE原油期货交割业务的具体执行流程,重点探讨交割业务中所涉及的保税入库相关执行问题,类比... 2018年3月26日,上海原油期货在上海期货交易所子公司上海国际能源交易中心(INE)正式上市交易,开启了中国期货市场国际化的新篇章。本文研究了INE原油期货交割业务的具体执行流程,重点探讨交割业务中所涉及的保税入库相关执行问题,类比一般贸易保税入库执行工作,对INE原油交割的保税入库环节进行分析并提出问题。针对这些问题,结合交割执行实际操作,本文提出了可行性建议及对策。 展开更多
关键词 ine原油期货 ine期货交割执行现状 问题及对策分析
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INES简介及我国推行INES的方式初探 被引量:1
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作者 张禄庆 《核动力工程》 EI CAS CSCD 北大核心 1992年第5期13-17,共5页
本文简单介绍了国际原子能机构(IAEA)向各成员国推荐使用的国际核事件分级表(INES)的出台背景、现状、评价标准及对一些重大核事件的分级示例。此外还对我国参加 INES 试用期间活动的方式、核电厂事件信息评价的传递途径及技术后援等提... 本文简单介绍了国际原子能机构(IAEA)向各成员国推荐使用的国际核事件分级表(INES)的出台背景、现状、评价标准及对一些重大核事件的分级示例。此外还对我国参加 INES 试用期间活动的方式、核电厂事件信息评价的传递途径及技术后援等提出初步看法。 展开更多
关键词 核电站 核事故 分级 ineS
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Fast fine acquisition algorithm of GPS receiver aided by INS information 被引量:6
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作者 Lufeng Zhu Chunxi Zhang Zhiqiang Ma 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2011年第2期300-305,共6页
Acquisition time of global position system (GPS) receiver, which is the main factor contributes to time to first fix (TTFF), can be shortened by estimating the Doppler frequency shift through external inertial nav... Acquisition time of global position system (GPS) receiver, which is the main factor contributes to time to first fix (TTFF), can be shortened by estimating the Doppler frequency shift through external inertial navigation system (INS) information and almanac data and reducing the searching area. The traditional fast acquisition is analyzed, the fast acquisition of the GPS receiver aided is presented by INS information, and the signal is fine captured by spectrum zooming. Then the algorithm is simulated by sampled GPS intermediate frequency (IF) signal and the result verifies that this acquisition can dramatically improve the capability of GPS receiver and reduce its acquisition time. 展开更多
关键词 inertial navigation system (INS) aid spectrum zooming acquisition time global position system (GPS) receiver.
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O-linked N-acetylglucosamine transferase(OGT) is overexpressed and promotes O-linked protein glycosylation in esophageal squamous cell carcinoma 被引量:2
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作者 Zhe Qiao Chengxue Dang +6 位作者 Bin Zhou Shaomin Li Wei Zhang Jiantao Jiang Jin Zhang Ranran Kong Yuefeng Ma 《The Journal of Biomedical Research》 CAS 2012年第4期268-273,共6页
The aim of this present study was to explore the expression and clinical significance of O-linked N-acetylglucosamine(O-GlcNAc) transferase(OGT) and enzymatic O-linked glycosylation(O-GlcNAcation) through the ad... The aim of this present study was to explore the expression and clinical significance of O-linked N-acetylglucosamine(O-GlcNAc) transferase(OGT) and enzymatic O-linked glycosylation(O-GlcNAcation) through the addition of O-linked-β-N-acetylglucosamine in esophageal squamous cell carcinoma.OGT expression and O-GlcNAcation in 40 samples from patients with esophageal squamous cell carcinoma was detected by immunohistochemical staining with anti-OGT antib ody and O-GlcNAc-specific antibody RL 2,respectively.The relationship between pathological and clinical factors of patients was analyzed.We found that the expression of OGT was higher in esophageal squamous cell carcinoma samples compared to the normal tissues.RL 2 antibody level was positively correlated with OGT expression,and the metastasis of lymph node,which means the level of O-GlcNAcation was high and related to the metastasis of lymph node in esophageal squamous cell carcinoma.In conclusion,OGT activation is the main reason for promoting the level of O-GlcNAcation in esophageal squamous cell carcinoma.O-GlcNAcylation may play an important role in esophageal squamous cell carcinoma. 展开更多
关键词 O-linked N-acetylglucosam ine(O-GlcNAc) transferase(OGT) O-linked glycosylation(O-GlcNAcation) esophageal squamous cell carcinoma
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INE原油期货实货交割存在的问题研究 被引量:3
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作者 高雅 《中国市场》 2019年第23期1-2,9,共3页
2018年3月26日原油期货于上海国际能源交易中心挂牌上市。上海国际能源交易中心对原油期货“国际平台、净价交易、保税交割、人民币计价”的设计思路,意在发展成为亚太——中东地区主打的中质含硫油的权威计价基准。目前全球两大基准原... 2018年3月26日原油期货于上海国际能源交易中心挂牌上市。上海国际能源交易中心对原油期货“国际平台、净价交易、保税交割、人民币计价”的设计思路,意在发展成为亚太——中东地区主打的中质含硫油的权威计价基准。目前全球两大基准原油期货为芝加哥商品交易所的WTI原油期货和伦敦洲际交易所的布伦特原油(BrentOil)期货。上海大致处于伦敦和纽约之间,恰好填补WTI、Brent全球交易时区空白,可以形成24小时的原油期货连续交易机制。交割是现货与期货价格在合约最后交易日时收敛的重要保障。原油期货实货交割环节是否通畅决定了投资者的参与度,为了促进更多的投资者参与到上海国际能源交易中心原油期货交易中,保证期货原油实货交割的顺畅就显得极为紧要。本文通过对中国原油期货实货交割规则及实际操作情况进行分析,对交割过程中遇到的问题进行阐述,就此提出建议。 展开更多
关键词 ine 原油期货实货交割 存在问题
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INE原油期货交易存在的问题研究 被引量:2
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作者 张德才 《中国市场》 2018年第35期53-54,59,共3页
2018年3月26日,INE原油期货正式挂牌上市。与WTI原油期货和Brent原油期货进行对比,分析了INE原油期货上市之日至5月24日期间的交易数据。通过交易数据、价格走势等因素的分析,发现INE原油期货交易中存在交易量、持仓量不足,市场波动较大... 2018年3月26日,INE原油期货正式挂牌上市。与WTI原油期货和Brent原油期货进行对比,分析了INE原油期货上市之日至5月24日期间的交易数据。通过交易数据、价格走势等因素的分析,发现INE原油期货交易中存在交易量、持仓量不足,市场波动较大,交易量过于集中等问题。提出了如何提高市场参与度,完善合约设计,加强制度建设等建议,为促进INE原油期货发展提供参考。 展开更多
关键词 ine原油期货 交易量 市场波动
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INE原油期货上市影响研究 被引量:1
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作者 白倩 《当代化工》 CAS 2018年第9期1906-1910,共5页
2018年3月26日,中国原油期货在上海期货交易所子公司上海国际能源交易中心(INE)正式挂牌交易,INE原油期货上市对我国能源行业具有重要的战略意义及影响。INE原油期货借助交易品种的差异化竞争、通过人民币结算等便利条件迅速打开原油期... 2018年3月26日,中国原油期货在上海期货交易所子公司上海国际能源交易中心(INE)正式挂牌交易,INE原油期货上市对我国能源行业具有重要的战略意义及影响。INE原油期货借助交易品种的差异化竞争、通过人民币结算等便利条件迅速打开原油期货交易市场,为我国石油行业经营参与者积极参与原油市场、套期保值、对冲交易风险、实现实物库存保值等提供了有利工具。 展开更多
关键词 ine原油期货 意义 影响 套期保值
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Influence of Seawall Line Choice on Tide Lock Drainage in Tidal Flat Inning——Cangdongpian Inning Area on the west part of Tiaozini Sand as a case study
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作者 李加林 王艳红 张忍顺 《Marine Science Bulletin》 CAS 2007年第1期55-65,共11页
Most of the flood from the wide inner lowland plain discharges through tide locks on coast, and the influence of tidal flat inning projects on the tide lock drainage must be solved by seawall line choice. Taking the C... Most of the flood from the wide inner lowland plain discharges through tide locks on coast, and the influence of tidal flat inning projects on the tide lock drainage must be solved by seawall line choice. Taking the Cangdongpian inning area on the west side of Tiaozini Sand as a case study, the paper analyzed the compages and validity of ebb tide water to maintain the flood discharge creek below the tide lock for different projects of seawall line. Result indicates that a rational seawall line program has little influence on the flood discharge of lock during the mean tide or general spring tides, but has certain influences during a storm surge or an extreme spring tide in autumn. However it could be resolved by several times of artificial scour on the creek. 展开更多
关键词 tidal flat inning tide lock DISCHARGE INFLUENCE
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一种新的负反馈放大器分析法——INE法
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作者 管庶安 《黄冈师范学院学报》 1989年第2期28-30,共3页
本文从研究负反馈放大器的输入回路出发,引进了过渡电压放大倍数Autrs 等量,导出了并联和串联负放大器的等效输入回路.使电路的计算大为简化,物理解释也十分明显.本文称此种新的分析方法为输入回路等效法,简记为 INE 法.
关键词 负反馈放大器 ine 输入回路 反馈放大电路 放大倍数 等效法 反馈类型 物理解释 输入电阻 输入级
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VIBRATIONAL SPECTROSCOPIC STUDY OF THE INTERACTION BETWEEN Ge-132 AND DIPALMITOYLPHOSPHATIDYLCHOL INE
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作者 Wei WANG Lai Ming LI Shi Quan XIChangchun Institute of Applied Chemistry,Academia Sinica,Changchun 130022 《Chinese Chemical Letters》 SCIE CAS CSCD 1992年第5期375-376,共2页
The vibrational spectra of both pure DPPC liposomes and DPPC multilayers reconstituted with Ge-132 are reported as a function of temperature from 290 to 330K.The results show that the addition of Ge-132 results in sup... The vibrational spectra of both pure DPPC liposomes and DPPC multilayers reconstituted with Ge-132 are reported as a function of temperature from 290 to 330K.The results show that the addition of Ge-132 results in suppression of the pretransition behavior and reduction of temperature of the main transition for reconstituted system.The results also show that the degree of rigidity of the acyl chain in the presence of Ge-132 is lower than that in pure DPPC dispersion within the investigated temperature range. 展开更多
关键词 DPPC VIBRATIONAL SPECTROSCOPIC STUDY OF THE INTERACTION BETWEEN Ge-132 AND DIPALMITOYLPHOSPHATIDYLCHOL ine Ge
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DGPS/INS Integration and Its Application in Railway Line Surveying
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《Journal of Modern Transportation》 1997年第2期31-36,共6页
In this paper, a method of railway line surveying system is proposed. This method can reduce the labour intensity in railway line surveying. It also can improve the work efficiency and overcome the obstruction to the ... In this paper, a method of railway line surveying system is proposed. This method can reduce the labour intensity in railway line surveying. It also can improve the work efficiency and overcome the obstruction to the ordinary operation of railways. 展开更多
关键词 DGPS/INS railway line real time surveying
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The Performance Evaluation of the Integration of Inertial Navigation System and Global Navigation Satellite System with Analytic Constraints
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作者 Thanh Trung Duong Nguyen Van Sang +1 位作者 Do Van Duong Kai-Wei Chiang 《Journal of Environmental Science and Engineering(A)》 2017年第6期313-319,共7页
The integration of GNSS (Global Navigation Satellite System) and INS (Inertial Navigation System) using IMU (Inertial Measurement Unit) is now widely used for MMS (Mobile Mapping System) and navigation applica... The integration of GNSS (Global Navigation Satellite System) and INS (Inertial Navigation System) using IMU (Inertial Measurement Unit) is now widely used for MMS (Mobile Mapping System) and navigation applications to seamlessly determine position, velocity and attitude of the mobile platform. With low cost, small size, ligh weight and low power consumtion, the MEMS (Micro-Electro-Mechanical System) IMU and low cost GPS (Global Positioning System) receivers are now the trend in research and using for many applications. However, researchs in the literature indicated that the the performance of the low cost INS/GPS systems is still poor, particularly, in case of GNSS-noise environment. To overcome this problem, this research applies analytic contrains including non-holonomic constraint and zero velocity update in the data fusion engine such as Extended Kalman Filter to improve the performance of the system. The benefit of the proposed method will be demonstrated through experiments and data analysis. 展开更多
关键词 GNSS (Global Navigation Satellite System) INS inertial Navigation System) NAVIGATION analytic constraints.
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CLINICAL ANALYSIS ON THE TREATMENT OF FACIAL PARALYSIS BY ACUPUNCTURE, MOXIBUSTION PLUS CHINESE HERBAL MEDICINES
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作者 张莉莎 申玮红 《World Journal of Acupuncture-Moxibustion》 2005年第1期46-49,51,共5页
Objective: To observe the therapeutic effect of the integrated acupuncture-moxibustio n and herbal therapies for facial paralysis. Methods: A total of 68 cases of facial paralysis were treated by integration of acupun... Objective: To observe the therapeutic effect of the integrated acupuncture-moxibustio n and herbal therapies for facial paralysis. Methods: A total of 68 cases of facial paralysis were treated by integration of acupunct ure-moxibustion and herbal therapies. For acu-moxibustion, Yifeng (翳风 TE 17) , Dicang (地仓 ST 4), Jiache (颊车 ST 6), Yangbai (阳白 GB 14), Hegu (合谷 LI 4), etc. were used. In addition, for facial palsy patients with wind-phlegm blockin g meridian-collaterals and wind-stirring due to yin defi ciency types in the acute stage, Modified Qian Zheng San (牵正散 Powder for Treating Wry-mouth) and Modi f ied Zhen Gan Xi Feng Tang (镇肝熄风汤 Tranquilizing Liver-wind Decoction) were u sed respectively; and for those in convalescent stage and sequela stage, Modifie d Danggui Bu Xue Tang (当归补血汤 Ghinese Angelica Decoction for Replenishing Bl ood) + Qian Zheng San (Powder for Treating Wry-mouth) and Modified Bu Yang Hu an Wu Tang (补阳还五汤 Decoction Invigorating Yang for Recuperation) were employed. Results: After the treatment, the curative rate of the 68 cases a ccounted for 90 % of the total cases, the remarkably effective 6%, the improved 3% and the poor 1% respectively. Conclusion: The therapeutic effectiveness of the integrated tre atment of acupuncture-moxibustion and herbal therapies for facial paralysis is certain. 展开更多
关键词 Facial paralysis acu-moxibustion Chinese herbal medic ine
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LYOTROPIC AND THERMOTROPIC LIQUID CRYSTALL INE TRIALKYL CELLULOSES OBTAINED DIRECTLY FROM CELLULOSE ACETATE IN DIMETHYL SULFOXIDE
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作者 Xin Gui LI, and Mei Rong HUANG~1 Institute of Membrane Separation Engineering, ~1Department of Textile Chemical Engineering, Tianjin Institute of Textite Science and Technology, Tianjin 300160 《Chinese Chemical Letters》 SCIE CAS CSCD 1992年第7期573-576,共4页
Highly substituted n-atkyl celluloses with sidechains 3 to 10 carbon atoms long have been prepared from cellulose acetate, sodium hydroxide and n-alkyl bromides with dimethyl sulfoxide as solvent. Synthetic conditions... Highly substituted n-atkyl celluloses with sidechains 3 to 10 carbon atoms long have been prepared from cellulose acetate, sodium hydroxide and n-alkyl bromides with dimethyl sulfoxide as solvent. Synthetic conditions of n-alkyl celluloses were studied with respect to reaction temperature, time and yield. The molecular structure of the n-alkyl celluloses, which were obtained as white powders or as sticky, soft and birefringent solids at room temperature, was investigated by IR and NMR spectra and elemental analysis. The highly substituted n-alkyl celluloses all exhibited both therotropic and lyotropic liquid crystalline cholesteric phases in some non-polar solvents. The metting behavior and solubility of the n-alkyl celluloses were examined. 展开更多
关键词 LYOTROPIC AND THERMOTROPIC LIQUID CRYSTALL ine TRIALKYL CELLULOSES OBTAineD DIRECTLY FROM CELLULOSE ACETATE IN DIMETHYL SULFOXIDE
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