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Mechanical Dispatch Reliability Prediction for Civil Aircraft Considering Operational Parameters

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Computer Modeling in Engineering & Sciences 2023年第3期134卷 1925-1942页

作者： Yunwen Feng Zhicen Song Cheng lu School of Aeronautics Northwestern Polytechnical UniversityXi’an710072China Department of Aeronautics and Astronautics Fudan UniversityShanghai200433China

To effectively predict the mechanical dispatch reliability(MDR),the artificial neural networks method combined with aircraft operation health status parameters is proposed,which introduces the real civil aircraft operation data for verification,to improve the modeling precision and computing *** relational analysis can identify the degree of correlation between aircraft system health status(such as the unscheduled maintenance event,unit report event,and services number)and dispatch release and screen out themost closely related systems to determine the set of input parameters required for the prediction *** artificial neural network using radial basis function(RBF)as a kernel function,has the best applicability in the prediction of multidimensional,small sample *** status parameters of related systems are used as the input to predict the changing trend ofMDR,under the artificial neural network modeling *** case study collects real operation data for a certain civil aircraft over the past five years to validate the performance of the model which meets the requirements of the *** results show that the prediction quadratic error Ep of the model reaches 6.9×10−*** is to say,in the existing operating environment,the prediction of the number of delay&cancel events per month can be less than *** accuracy of RBF ANN,BP ANN and GA-BP ANN are compared further,and the results show that RBF ANN has better adaptability to such multidimensional small sample *** efforts of this paper provide a highly efficientmethod for theMDR prediction through aircraft system health state parameters,which is a promising model to enhance the prediction and controllability of the dispatch release,providing support for the construction of the civil aircraft operation system.

关键词： Mechanical dispatch reliability GRA-RBF civil aircraft artificial neural network

Experimental Study on Coal Multi-generation in Dual Fluidized Beds

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Journal of Thermal Science 2007年第3期16卷 277-282页

作者： Fan Xiaoxu lu Qinggang Na Yongjie Liu Qi Institute of Engineering Thermophysics Chinese Academy of Sciences Beijing 100080 China Graduate School of the Chinese Academy of Sciences Beijing 100080 China

An atmospheric test system of dual fluidized beds for coal multi-generation was built. One bubbling fluidized bed is for gasification and a circulating fluidized bed for combustion. The two beds are combined with two valves： one valve to send high temperature ash from combustion bed to the gasification bed and another valve to send char and ash from gasification bed to combustion bed. Experiments on Shenhua coal multi-generation were made at temperatures from 1112 K to 1191 K in the dual fluidized beds. The temperatures of the combustor are stable and the char combustion efficiency is about 98%. Increasing air/coal ratio to the fluidized bed leads to the increase of temperature and gasification efficiency. The maximum gasification efficiency is 36.7% and the calorific value of fuel gas is 10.7 mj/Nm^3. The tar yield in this work is 1.5%, much lower than that of pyrolysis. Carbon conversion efficiency to fuel gas and flue gas is about 90%.

关键词： gasification multi-generation dual fluidized beds tar char combustion

基于B-L气动模型的旋转水平风机叶片经典颤振稳定性分析

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振动与冲击 2015年第23期34卷 171-176页

作者：李迺璐穆安乐 Balas M J 扬州大学水利与能源动力工程学院江苏扬州225127 西安理工大学机械与精密仪器工程学院西安710048 美国安柏瑞德航空航天大学航空学院美国32114

研究旋转水平轴风力机叶片周期时变气弹系统的经典颤振稳定性特性。叶片结构采用具有挥舞和扭转耦合的典型界面振动模型,引入Beddoes-Leishman气动模型为旋转叶片提供低攻角处周期时变的非定常气动力;为了研究颤振边界,利用标量风速和挥... 详细信息

研究旋转水平轴风力机叶片周期时变气弹系统的经典颤振稳定性特性。叶片结构采用具有挥舞和扭转耦合的典型界面振动模型,引入Beddoes-Leishman气动模型为旋转叶片提供低攻角处周期时变的非定常气动力;为了研究颤振边界,利用标量风速和挥舞/扭转固有频率比对所建立的旋转叶片气弹模型进行变型。在此基础上,通过时域响应曲线分析旋转叶片挥舞自由度和扭转自由度气弹稳定性特性,分析了标量速度,叶片刚度,挥舞/扭转固有频率比和结构阻尼的影响,揭示了旋转叶片经典颤振边界的变化规律且其准确性得到验证。

关键词：旋转风机叶片经典颤振气弹模型稳定性

基于Floquet理论的旋转风机叶片动力失速气弹稳定性研究

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振动与冲击 2015年第24期34卷 82-88页

研究旋转风力机叶片动力失速气弹稳定性问题。叶片结构采用标量化的挥舞和扭转自由度耦合的振动运动模型,旋转风机叶片的气动力由Beddoes-Leishman失速模型来模拟,通过攻角在深度失速区域内的变化来计算出周期时变的非线性气动失速负载... 详细信息

研究旋转风力机叶片动力失速气弹稳定性问题。叶片结构采用标量化的挥舞和扭转自由度耦合的振动运动模型,旋转风机叶片的气动力由Beddoes-Leishman失速模型来模拟,通过攻角在深度失速区域内的变化来计算出周期时变的非线性气动失速负载。在系统静平衡点附近对非线性气弹系统进行线性化,采用Floquet理论分析旋转叶片动力失速气弹稳定性,其结果得到系统时域响的验证。通过数值分析,揭示了挥舞扭转固有频率比和结构阻尼对颤振边界的影响。

关键词：旋转风机叶片气动失速 Floquet理论 Beddoes-Leishman模型

A Novel Humidity-Sensitive Material Based on PDEB with Nickel Complex Catalyst

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Chinese Chemical Letters 1998年第2期9卷 223-225页

作者： Yang, mj Li, Y Zhan, XW Sun, HM Ling, MF Zhu, YH Zhejiang Univ Dept Polymer Sci & Engn Hangzhou 310027 Peoples R China Zhejiang Univ Dept Elect & Informat Hangzhou 310027 Peoples R China

Poly(p-diethynylbenzene) (PDEB) with improved solubility was synthesized using a novel catalyst bis(triphenylphosphine)bis(p-diethynylbenzene) nickel complex (NI-C). A surface acoustic wave (SAW) delay line oscillator was covered by Langmuir-Blodgett (LB) films of resulting PDEB to prepare a humidity sensor, which was found to have high sensitivity and good repeatability. PDEB shows promise as a good humidity-sensitive material.

关键词： humidity-sensitive material bis(triphenylphosphine)bis(p-diethynylbenzene) nickel poly (p-diethynylbenzene) SAW humidity sensor LB membrane

Nonalcoholic fatty liver disease: An overview of current insights in pathogenesis, diagnosis and treatment

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World Journal of Gastroenterology 2008年第16期14卷 2474-2486页

作者： Tim CMA Schreuder Bart J Verwer Carin mj van Nieuwkerk Chris JJ Mulder Department of Gastroenterology and Hepatology VU University Medical Center

Estimates of people suffering from overweight (one billion) and obesity (300 million) are increasing. The accumulation of triglycerides in the liver, in the absence of excess alcohol intake, has been described in the early sixties. It was not until 1980, however, that ludwig et al named this condition nonalcoholic steatohepatitis (NASH). Subsequently, nonalcoholic fatty liver disease (NAFLD) has been used as a general name for conditions ranging from simple steatosis through steatohepatitis to end-stage liver disease (cirrhosis). Many studies have demonstrated the significant correlation with obesity and insulin resistance. Other studies have revealed a signifi- cant correlation between hepatic steatosis, cardiovascu- lar disease and increased intima-media thickness. WHO estimated that at least two million patients will develop cirrhosis due to hepatic steatosis in the years to come. Longitudinal cohort studies have demonstrated that those patients with cirrhosis have a similar risk to devel- op hepatocellular carcinoma as those with other causes of cirrhosis. Taken all together, NAFLD has become the third most important indication for liver transplantation. There- fore, training programmes in internal medicine, gastroen- terology and hepatology should stress the importance of diagnosing this entity and treat properly those at risk for developing complications of portal hypertension and con- comittant cardiovascular disease. This review will focus on the clinical characteristics, pathophysiology, imaging tech- niques and the readily available therapeutic options.

关键词： Non-alcoholic fatty liver disease Non-alcoholicsteatohepatitis Insulin resistance Liver Obesity Steatosis

The discovery of eclogite dikes in low-greenschist facies volcaniclastic rocks of the Dabie Mountains

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Chinese Science Bulletin 1997年第20期42卷 1726-1729页

作者： Gao, TS Tang, JF Zhou, CT Hou, mj Qian, CC Reg Geol Survey Anhui Prov Hefei 230011 Peoples R China

ECLOGITE occurs in different metamorphic rocks in the Dabie Mountains. Some dike-likeeclogite and garnet amphibolite were discovered when we investigated the newly founded low-greenschist facies volcaniclastic rocks in Changpu, Yuexi County and Siqian, Taihu County(fig.1). Coesite and quartz pseudomorphs exist in garnet and omphacite. By studying the oc-currence and petrography-mineralogy characteristic, we believe that the eclogite is of

关键词： eclogite dike magmatic origin low-greenschist facies volcaniclastic rocks Dabie Monntains areas.

Population genetic structure of Culex quinquefasciatus in India by ISSR marker

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Asian Pacific Journal of Tropical Medicine 2011年第5期4卷 357-362页

作者： Mendki mj Sharma AK Vijay Veer Agrawal OP Shri Prakash Parashar BD Entomology Division Defence R & D EstablishmentJhansi RoadGwaliorMadhya PradeshIndia School of Studies in Zoology Jiwaji UniversityGwaliorMadhya PradeshIndia Entomology Division Defence R&D EstablishmentJhansi RoadGwaliorMadhya PradeshIndia

Objective:To characterize the genetic structure of various populations of Culex quinquefasciatus (***) from India representing different geoclimatic ***:Inter simple sequence repeat(ISSR) markers were used.A set of 20 primers were screened with the laboratory populations of mosquito *** the IS 40 primer was chosen based on the scorable banding pattern showing 100 percent polymorphism among the various *** statistical analysis was done using POPGENE 1.31 *** consensus tree was generated based on UPGMA modified from NEIGHBOR procedure of PHYLIP Version ***:The cluster analysis shows the main cluster which is divided into two sub cluster representing all the populations separated as per their phylogeographic and geoclimatic ***: The findings will be helpful in understanding the population variation under different ecological conditions and development of effective vector management strategies.

关键词： Genetic structure Culex quinquefasciatus ISSR marker India

Development of an experimental method for well-controlled blast induced traumatic limb fracture in rats

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Defence Technology（防务技术） 2024年第4期34卷 168-176页

作者： luyang Xu Xiancheng Yu Clement DFavier Ibidumo Igah Thuy-Tien Nguyen Warren Macdonald Anthony mj.Bull Centre for Blast Injury Studies Imperial College LondonLondonUnited Kingdom Department of Bioengineering Imperial College LondonLondonUnited Kingdom Dyson School of Design Engineering Imperial College LondonLondonUnited Kingdom Department of Trauma and Orthopaedics Royal Free London National Health Service Foundation TrustLondonUnited Kingdom

Heterotopic ossification(HO)is a consequence of traumatic bone and tissue damage,which occurs in 65%of military casualties with blast-associated ***,the mechanisms behind blast-induced HO remain *** models are used to study blast-induced HO,but developing such models is challenging,particularly in how to use a pure blast wave(primary blast)to induce limb fracture that then requires an *** studies,including our recent study,have developed platforms to induce limb fractures in rats with blast loading or a mixture of blast and impact ***,these models are limited by the survivability of the animal and repeatability of the *** this study,we developed an improved platform,aiming to improve the animal's survivability and injury repeatability as well as focusing on primary blast *** platform exposed only one limb of the rat to a blast wave while providing proper protection to the rest of the rat's *** obtained very consistent fracture outcome in the tibia(location and pattern)in cadaveric rats with a large range of size and ***,the rats did not obviously move during the test,where movement is a potential cause of uncontrolled *** further conducted parametric studies by varying the features of the design of the *** factors,such as how the limb is fixed and how the cavity through which the limb is placed is sealed,significantly affect the resulting *** platform and test setups enable well-controlled limb fracture induced directly by pure blast wave,which is the fundamental step towards a complete in vivo animal model for blast-induced HO induced by primary blast alone,excluding secondary and tertiary blast *** addition,the platform design and the findings presented here,particularly regarding the proper protection of the animal,have implications for future studies investigating localized blast injuries,such as blast induced brain and lung injuries.

关键词： Blast injury Biomechanics Heterotopic ossification Limb fracture Blast wave Animal model