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The impact of climate change on forest fire danger rating in China’s boreal forest

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Journal of Forestry Research 2011年第2期22卷 249-257页

作者： YANG Guang DI Xue-ying guo qing-xi SHU Zhan ZENG Tao YU Hong-zhou WANG Chao College of Forestry Northeast Forestry University Harbin 150040 P.R.China.

The Great Xing＇an Mountains boreal forests were focused on in the northeastern *** simulated future climate scenarios of IPCC SRES A2a and B2a for both the baseline period of 1961-1990 and the future scenario periods were downscaled by the Delta Method and the Weather Generator to produce daily weather *** the verification with local weather and fire data,the Canadian Forest Fire Weather Index System was used to assess the forest fire weather situation under climate change in the study *** increasing trend of fire weather severity was found over the 21st century in the study region under the both future climate change scenarios,compared to the 1961-1990 baseline *** annual mean/maximum fire weather index was predicted to rise continuously during 2010-2099,and by the end of the 21st century it is predicted to rise by 22%-52% across much of China＇s boreal *** significant increases were predicted in the spring from of April to June and in the summer from July to *** the summer,the fire weather index was predicted to be higher than the current index by as much as 148% by the end of the 21st *** the scenarios of SRES A2a and B2a,both the chance of extremely high fire danger occurrence and the number of days of extremely high fire danger occurrence was predicted to increase in the study *** is anticipated that the number of extremely high fire danger days would increase from 44 days in 1980s to 53-75 days by the end of the 21st century.

关键词： climate change wildfire boreal forest fire weather species West Africa

Study on Preparation and Release of Dexamethasone Hyaluronan Microspheres

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Chinese Journal of Biomedical Engineering(English Edition) 2007年第3期16卷 93-100,116页

作者： HU guo-ying GU Han-qing The Second Hospital of Tianjin Medical University Tianjin 300211 China

Hyaluronan (HA), the consistent glycosaminoglycans in extracellular matrix, is a kind of biomaterials with wonderful biocompatibility. To develop drug release system (DDS) with HA as drug carrier is a new hotspot in the field of pharmaceutics. In this paper, we applied technique of ultrosound and reversed phase (Water/Oil) emulsification to develop dexamethasone (DEX)-HA-STMP cross-linking microspheres (DEX-HA MS) with STMP as cross-linker. DEX-HA MS has a wonderful shape and property of dispersion. There is a negative correlation between diameter of DEX-HA MS and the content of cross-linker, or the content of emulsifier, and a positive correlation between the diameter and CHA . When CHA≤1%,DEX/HA≤1/10 (g/g),there is a positive correlation between the factors mentioned below and drug loading (DL%)/loading efficiency (LE%),the content of STMP, the content of emulsifier,CHA and the content of DEX. DEX-HA-MS can realize function of slow release. In vitro drug release experiment shows that cumulative release (CR%) of DEX-HA MS fits in with pervasion-corrosion equation, and there is a negative correlation between the content of STMP, CHA and CR%, a positive correlation between emulsifier and CR%. When DEX/HA≤1/5 (g/g) there is a negative correlation between the content of DEX and CR%.

关键词： hyaluronan (HA) dexamethasone drug delivery system microspheres cross-linking ultrasound emulsification

Study on Biological Properties of HA-TMP Cross-linked Products

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Chinese Journal of Biomedical Engineering(English Edition) 2010年第2期19卷 56-65页

作者： LIU Xin HU guo-ying GU Han-qing Tianjin Institute of Urological Surgery Tianjin 300211 China

Objective:In the medium of ethanol(non-polar),STMP and ADH as crosslinkers to HA,to prepare drug delivery microspheres by getting stable cross-linked products without a gel phase,and to study biocompatibility and biodegradability of cross-linked ***:ISO10993.1-Safety Evaluation of Biomedical materials as a reference,to make hemolysis test,percutaneous stimulation test,acute toxicity test,and analyze in vitro degradation test,and degradation ***:HA-STMP cross-linked product had no hemolysis,no irritation,no acute systemic toxicity,but HA-ADH had a mild skin irritation and adverse acute systemic ***-STMP cross-linked product had lower sensitivity on HAse and the curve is *** the increase of degradation time HA-STMP results were changed by the structure analysis,degradation products of these cells were no ***:HA-STMP cross-linked products with better biocompatibility and better resistance to hydrolysis could delay the degradation time,which is suitable for the preparation of biodegradable drug carriers.

关键词： drug delivery biocompatibility biodegradability

Study on Biocompatibility of Cross-linked Hyaluronic Acid Derivatives

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Chinese Journal of Biomedical Engineering(English Edition) 2009年第3期18卷 93-101页

作者： LIU Xin HU guo-ying GU Han-qing Tianjin Institute of Urological Surgery Tianjin 300211 China

Objective:The cross-linked production,which was prepared by HA and cross-linking agent STMP,EDC,GP through cross-linking reaction,might be used in drug delivery system(DDS).To ensure the security of clinical application,the excellent properties such as none cell toxicity,nonirritant,none general toxicity,none immunological rejection are ***:In accordance with the request of GB/T 16886.1 on security evaluation of medical biomaterials,cell toxicity test,hemolysis test,intracutaneous stimulation test,acute toxicity test,and hypersensitive test were ***:Cell toxicity of HA-STMP,HA-EDC,HA-GP were all less than *** hypersensitive tests were *** HA-EDC,HA-GP produced different degrees of slight thrill,slight toxicity,hemolysis rate,which were larger than the standard ***:HA-STMP possesses favourable biocompatibility,which is a kind of ideal biomaterials and drug carriers.

关键词： hyaluronan (HA) cross-linked production biocompatibility

采用序列概率比方法检测航空发动机传感器软故障

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航空动力学报 2007年第11期22卷 1925-1929页

作者：薛薇郭迎清西北工业大学动力与能源学院西安710072

提出基于卡尔曼滤波和序列概率比方法进行某型涡扇发动机控制系统传感器软故障检测新方法.研究了采用修正的序列概率比方法处理滤波残差,检测传感器软故障;并将该方法与残差加权二乘算法WSSR(Weighted Sum of Squared Residual)检测传... 详细信息

提出基于卡尔曼滤波和序列概率比方法进行某型涡扇发动机控制系统传感器软故障检测新方法.研究了采用修正的序列概率比方法处理滤波残差,检测传感器软故障;并将该方法与残差加权二乘算法WSSR(Weighted Sum of Squared Residual)检测传感器软故障过程进行了对比.仿真结果表明,序列概率比方法较WSSR法所需决策时间短,适合于航空发动机传感器软故障检测.

关键词：航空航天推进系统传感器故障诊断序列概率比卡尔曼滤波器故障检测与隔离(FDI)

基于RBF网络辨识的涡扇发动机双变量神经网络PID解耦控制

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航空动力学报 2007年第8期22卷 1391-1395页

作者：杨华郭迎清西北工业大学动力与能源学院西安710072

根据神经网络与PID算法相结合的思想,针对涡扇发动机双变量控制中变量之间的耦合问题,提出基于径向基函数神经网络(RBF)辨识的发动机双变量神经网络PID解耦控制,并给出控制系统的控制结构及原理.仿真结果表明,该方法控制精度高、跟踪性... 详细信息

根据神经网络与PID算法相结合的思想,针对涡扇发动机双变量控制中变量之间的耦合问题,提出基于径向基函数神经网络(RBF)辨识的发动机双变量神经网络PID解耦控制,并给出控制系统的控制结构及原理.仿真结果表明,该方法控制精度高、跟踪性能强、鲁棒性良好,能够有效地减小各回路之间的耦合影响,并保证控制系统具有良好的稳态和动态性能,适合航空发动机控制.

关键词：航空、航天推进系统涡扇发动机双变量控制径向基函数神经网络(RBF) 解耦

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榧属植物活性成分与药理作用研究进展

中草药 2007年第11期38卷 1747-1750页

作者：王鸿郭涛应国清浙江工业大学药学院浙江杭州310014

香榧始载于《神农本草经》,是我国特有的经济树种。榧属植物中含有丰富的挥发油、萜类、黄酮类等活性成分,具有良好的抗肿瘤、抗病毒、驱虫、降血压及子宫收缩等药理活性。以国内外近期文献为依据,主要介绍了榧属植物的化学及药理研究情... 详细信息

香榧始载于《神农本草经》,是我国特有的经济树种。榧属植物中含有丰富的挥发油、萜类、黄酮类等活性成分,具有良好的抗肿瘤、抗病毒、驱虫、降血压及子宫收缩等药理活性。以国内外近期文献为依据,主要介绍了榧属植物的化学及药理研究情况,为进一步开展该属植物的化学成分和药理研究提供参考。

关键词：榧属香榧紫杉醇

基于GA-AANN神经网络的SDQ算法的航空发动机传感器数据预处理

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推进技术 2018年第5期39卷 1142-1150页

作者：吕升郭迎清孙浩西北工业大学动力与能源学院陕西西安710129

为实现对输入健康管理系统的航空发动机传感器数据进行数据鉴定、故障诊断以及去除噪声信号干扰,提出了一种航空发动机传感器数据预处理方法。针对双通道传感器航空涡扇发动机,搭建了以合理性检验模块和解析冗余检验模块为主要内容的SD... 详细信息

为实现对输入健康管理系统的航空发动机传感器数据进行数据鉴定、故障诊断以及去除噪声信号干扰,提出了一种航空发动机传感器数据预处理方法。针对双通道传感器航空涡扇发动机,搭建了以合理性检验模块和解析冗余检验模块为主要内容的SDQ算法模型,利用遗传算法优化的AANN神经网络实现传感器的解析冗余检验。采用蒙特卡罗仿真方法,将改进的SDQ算法与一种基于最小二乘法的SDQ算法进行对比仿真验证。结果表明,本文提出的SDQ算法在发动机稳态条件下对阶跃故障和漂移故障隔离的平均正确率分别提高了1.7%和19.1%,在发动机动态条件下对阶跃故障和漂移故障隔离的平均正确率分别提高了12.5%和33.8%。且在多传感器故障诊断和除噪方面性能优异,处理后的传感器信号平均信噪比提高了8.27dB。

关键词：航空发动机传感器故障诊断 SDQ算法遗传算法 AANN神经网络

基于非线性模型预测控制方法的航空发动机约束管理

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航空动力学报 2015年第7期30卷 1766-1771页

作者：杜宪郭迎清陈小磊西北工业大学动力与能源学院西安710072

针对目前航空发动机控制系统普遍采用Min-Max选择逻辑处理输出量约束的方法具有一定保守性的问题,设计了非线性模型预测控制器,提出在非线性序列二次规划(SQP)算法中加入罚函数实现航空发动机输出量约束管理.仿真结果表明:无论是否触及... 详细信息

针对目前航空发动机控制系统普遍采用Min-Max选择逻辑处理输出量约束的方法具有一定保守性的问题,设计了非线性模型预测控制器,提出在非线性序列二次规划(SQP)算法中加入罚函数实现航空发动机输出量约束管理.仿真结果表明:无论是否触及输出量约束限,非线性模型预测控制器都比Min-Max控制逻辑动态响应更快,在达到限制线时更加明显,此时调节时间从1.16s下降到0.82s,且几乎没有超调量.

关键词：约束管理航空发动机 Min-Max选择非线性模型预测控制罚函数序列二次规划