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Applied mathematics and mechanics(english edition) 2016年第7期37卷 821-834页

作者： m.AReFI R.KARROUBI m.IRANI-RAHAGHI Department of Solid mechanics Faculty of Mechanical EngineeringUniversity of Kashan

An analytical method for the three-dimensional vibration analysis of a functionally graded cylindrical shell integrated by two thin functionally graded piezoelectric （FGP） layers is presented. The first-order shear deformation theory is used to model the electromechanical system. Nonlinear equations of motion are derived by considering the von Karman nonlinear strain-displacement relations using Hamilton＇s principle. The piezoelectric layers on the inner and outer surfaces of the core can be considered as a sensor and an actuator for controlling characteristic vibration of the system. The equations of motion are derived as partial differential equations and then discretized by the Navier method. Numerical simulation is performed to investigate the effect of different para- meters of material and geometry on characteristic vibration of the cylinder. The results of this study show that the natural frequency of the system decreases by increasing the non-homogeneous index of FGP layers and decreases by increasing the non-homogeneous index of the functionally graded core. Furthermore, it is concluded that by increasing the ratio of core thickness to cylinder length, the natural frequencies of the cylinder increase considerably.

关键词： free vibration nonlinear analysis frequency analysis cylindrical shell,functionally graded material (FGm) functionally graded piezoelectric material (FGPm)

Computational Simulation of Feedback Linearised Control of a motorised momentum exchange Tether on a Circular earth Orbit

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Computational Simulation of Feedback Linearised Control of a...

慢性阻塞性肺疾病患者居家肺康复维持现状及影响因素研究

The Sixth World Congress on Computational mechanics in Conjunction with the Second Asian-Pacific Congress on Computational mechanics

作者： e.mouterde m.P.Cartmell cole Department of mechanical engineering University of Glasgow Glasgow G12 8QQ Scotland UK

Feedback Linearisation lends itself to many applications underpinned by systems of nonlinear second order ODes, for which the target states can readily be assigned a priori. This paper seeks to explore how systems respond to such control when their dynamics can change due to certain key physical parameter variations, in terms of a specific application of Space engineering relevance. The application chosen for this research is the novel motorised momentum exchange Tether, as recently proposed for interplanetary payload transfer, and in this case the cancellation of the nonlinear terms is not guaranteed when quantities in the plant (i.e. the tether) change for some physically justifiable reason. This could lead to incomplete control when these changes are not, or cannot be, tracked and appropriately cancelled by the controller. In the case of debris impacts it is quite likely that permanent damage could occur, which could certainly introduce significant variations in component masses and mass moments of inertia. If left unchecked even relatively minor changes to key system masses and mass moments of inertia would alter the dynamical performance of the system to the point where it no longer behaves in a predictable manner. This paper investigates the general problem of unexpected changes to two parameters in the motorised momentum exchange tether context, with spin-up control applied specifically by means of conventional feedback linearisation with adaptive gains.

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中华护理杂志 2024年第17期59卷 2077-2083页

作者：张明月田玉梅高娥王洁幸超群武悦宁夏医科大学护理学院银川市750000 湖南医药学院护理学院右江民族医学院

目的了解慢性阻塞性肺疾病(简称“慢阻肺”)患者居家肺康复维持现状及影响因素。方法采用便利抽样法,于2023年12月—2024年2月,选取在湖南省怀化市2所三级甲等医院门诊和1所社区卫生服务中心接受随访的392例慢阻肺患者为调查对象。采用... 详细信息

目的了解慢性阻塞性肺疾病(简称“慢阻肺”)患者居家肺康复维持现状及影响因素。方法采用便利抽样法,于2023年12月—2024年2月,选取在湖南省怀化市2所三级甲等医院门诊和1所社区卫生服务中心接受随访的392例慢阻肺患者为调查对象。采用一般资料调查表、慢阻肺评价测试量表、改良版英国医学研究委员会呼吸困难量表、锻炼益处/障碍量表和双向社会支持量表进行调查。结果共发放问卷392份,回收有效问卷362份,有效问卷回收率为92.47%。从未进行过居家肺康复的慢阻肺患者占56.08%,居家肺康复的健康行为维持时间为1~3个月的患者占17.40%,4~6个月的患者占7.18%,7~12个月的患者占4.70%,1年以上的患者占14.64%。多元线性回归分析结果显示,适合的运动场所、接受过肺康复健康教育、患慢阻肺前的运动习惯、锻炼行为感知水平和双向社会支持是慢阻肺患者居家肺康复维持时间的影响因素,可解释38.5%的变异度。结论慢阻肺患者的居家肺康复健康行为维持水平较低,应加强对慢阻肺患者及照顾者的运动康复健康教育,提升患者锻炼行为感知水平、社会支持的利用能力。

关键词：肺疾病慢性阻塞性居家维持性肺康复护理

Acute Oxygen Therapy: An Audit of Prescribing and Delivery Practices in the medical Wards at Dr. George mukhari Academic Hospital, Pretoria, Gauteng

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Open Journal of Respiratory Diseases 2022年第3期12卷 75-82页

作者： e. A. Akazie m. J. mpe Sefako-makgathu Health Sciences University Ga-Rankuwa South Africa

Background: Oxygen is a commonly used drug in modern medical care. It has biochemical actions, safe dosage ranges, adverse physiologic effects and can be toxic at high doses and prolonged use. As a drug, it needs a formal prescription prior to administration. The prescription needs to meet certain basic minimums for appropriateness and safety. Objectives: The aim of the study was to assess the standards of prescriptions for oxygen therapy amongst admitted medical patients at the Dr. George mukhari Academic Hospital. materials and methods: It was a cross-sectional study of 159 acutely ill medical admissions who received supplemental oxygen. The medication charts of patients on oxygen were audited;with regards to the availability and/or adequacy of the prescription for oxygen. Results: Of the one hundred and fifty nine patients on oxygen only 43 (27%) had an actual prescription for oxygen written. The target oxygen saturation was specified in 19 (44%) cases. The device for oxygen delivery was specified in 21 (49%) patients and just over half of the patients (56%) had flow rates indicated on their charts. Conclusion: The practice of oxygen administration in our medical wards was sub-optimal. The audit highlights the need for education and training in acute oxygen therapy.

关键词： Oxygen Targets Devices Flow Rates

Reliability and variance-based sensitivity analysis of arch dams during construction and reservoir impoundment

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Frontiers of Structural and Civil engineering 2019年第3期13卷 526-541页

作者： m.Houshmand KHANeGHAHI m.ALemBAGHeRI N.SOLTANI Department of Civil engineering Shahid Beheshti UniversityTehranIran Department of Civil and environmental engineering Tarbiat Modares UniversityTehranIran

The static performance of arch dams during construction and reservoir impoundment is assessed taking into account the effects of uncertainties presented in the model properties as well as the loading *** arch dam is chosen as the case study;it is modeled along with its rock foundation using the finite element method considering the stage *** previous studies concentrated on simplified models and approaches,comprehensive study of the arch dam model along with efficient and state-of-the-art uncertainty methods are incorporated in this *** reliability method is performed to assess the safety level and the sensitivity analyses for identifying critical input factors and their interaction effects on the response of the *** sensitivity analysis based on improved Latin hypercube sampling is employed in this study to indicate the influence of each random variable and their interaction on variance of the *** levels of model advancement are considered for the dam foundation system:1)monolithic dam without any joint founded on the homogeneous rock foundation,2)monolithic dam founded on the inhomogeneous foundation including soft rock layers,3)jointed dam including the peripheral and contraction joints founded on the homogeneous foundation,and 4)jointed dam founded on the inhomogeneous *** each model,proper performance indices are defined through limit-state *** this manner,the effects of input parameters in each performance level of the dam are *** outcome of this study is defining the importance of input factors in each stage and model based on the variance of the dam ***,the results of sampling are computed in order to assess the safety level of the dam in miscellaneous loading and modeling conditions.

关键词： concrete arch dams reliability randomness improved Latin hypercube sampling variance-based sensitivity analysis exceedance probability Sobol index

The Comparison of the Forms of Land Capability Classification of Atalay and USA in eskişehir Province (Turkey)

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Journal of Geoscience and environment Protection 2016年第13期4卷 72-92页

作者： mücahit Coşkun Ayşe Nur Uzun Turan Geography Department Karabük University Karabük Turkey

Turkey is an area where climate changes immediately, vegetation, or land gets different in a short distance. Geological and lithological features show diversity. Also, our country’s territorial existence and diversity also bring about different land use conditions. Therefore, land capability also differs from each other. Nevertheless, the classification of land capability used in Turkey is the classification of land capability for agricultural lands prepared by the United States (USA) in 1961. Due to this, [1] have made suggestion on a new classification of land capability considering our country’s geographical conditions. In this study, comparing the land capability with the classification carrying out in our country, the classification which Atalay and Gündüzoğlu suggested, has been aimed. Working method has been established according to regional approach and field observations have been done. In preparing the cartographical material, ArcGIS 10.3 has been used. The map of this study as a material topography, physical map, slope, aspect, the usage of the land, ground, geology, land capability, geomorphology, temperature, and precipitation has been examined, meteorological data have been appreciated. According to the findings attained, eskişehir’s map of land capability has been done through the criteria of the suggestions of Atalay and Gündüzoğlu. As a result, it has been understood that there is a difference between the USA land capability that applied in eskişehir and Atalay and Gündüzoğlu’s criteria. In the study, it is suggested to determine the land capabilities again considering the ecological conditions of Turkey.

关键词： The USA Land Capability Atalay Land Capability Classification Landuse Geography eskişehir Turkey

Sizing of hybrid PmSG-PV system for battery charging of electric vehicles

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Frontiers in energy 2015年第1期9卷 68-74页

作者： m. m. RAJAN SINGARAVeL S. ARUL DANIeL Department of electrical and electronics engineering National Instituteof Technology Tiruchirappalli 620015 India

The number of electric vehicles are increasing in the society as they are considered as zero emission vehicles and also because conventional fuels are becoming expensive. Additional electrical power should be produced to meet the energy requirement of this increase in electric vehicle population. To use the existing grid infrastructure without any failure, installing distributed generator at secondary distribution network is essential. In this work, sizing of wind-driven permanent magnet synchronous generator photovoltaic hybrid distributed generating system has been attempted to meet the energy demand of electric vehicles of a particular residential area. Different feasible combinations for wind generator capacity and photovoltaic capacity are obtained to satisfy the additional energy requirement. Results are analyzed based on energy, financial payback periods and daily power profile of the hybrid system. Based on this analysis, the sizes of wind generator and photovoltaic array have been chosen to meet the energy demand of electric vehicles of that particular residential locality.

关键词： electric vehicles hybrid PmSG-PV system,smart grid

HLR-Net: A Hybrid Lip-Reading model Based on Deep Convolutional Neural Networks

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Computers, materials & Continua 2021年第8期68卷 1531-1549页

作者： Amany m.Sarhan Nada m.elshennawy Dina m.Ibrahim Department of Computers and Control engineering Faculty of EngineeringTanta UniversityTanta37133Egypt Department of Information Technology College of ComputerQassim UniversityBuraydah51452Saudi Arabia

Lip reading is typically regarded as visually interpreting the speaker’s lip movements during the *** is a task of decoding the text from the speaker’s mouth *** paper proposes a lip-reading model that helps deaf people and persons with hearing problems to understand a speaker by capturing a video of the speaker and inputting it into the proposed model to obtain the corresponding *** deep learning technologies makes it easier for users to extract a large number of different features,which can then be converted to probabilities of letters to obtain accurate *** proposed methods for lip reading are based on sequence-to-sequence architectures that are designed for natural machine translation and audio speech ***,in this paper,a deep convolutional neural network model called the hybrid lip-reading(HLR-Net)model is developed for lip reading from a *** proposed model includes three stages,namely,preprocessing,encoder,and decoder stages,which produce the output *** inception,gradient,and bidirectional GRU layers are used to build the encoder,and the attention,fully-connected,activation function layers are used to build the decoder,which performs the connectionist temporal classification(CTC).In comparison with the three recent models,namely,the LipNet model,the lip-reading model with cascaded attention(LCANet),and attention-CTC(A-ACA)model,on the GRID corpus dataset,the proposed HLR-Net model can achieve significant improvements,achieving the CeR of 4.9%,WeR of 9.7%,and Bleu score of 92%in the case of unseen speakers,and the CeR of 1.4%,WeR of 3.3%,and Bleu score of 99%in the case of overlapped speakers.

关键词： lip-reading visual speech recognition deep neural network connectionist temporal classification

Structural morphological and Optical Properties of SnSb_2S_4 Thin Films Grown by Vacuum evaporation method

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Journal of materials Science & Technology 2014年第10期30卷 1006-1011页

作者： N.Khedmi m.Ben Rabeh m.Kanzari Laboratoire de Photovoltaques et matriaux de Semi-conducteurs-eNIT-Universit de Tunis el manar BP 37le belvedere1002 TunisTunisie Laboratoire de Photovoltaques et matriaux de Semi-conducteurs-eNIT-IPeITunis montfleury-Universit de Tunis Tunisie

SnSb2S4 thin films were prepared from powder by thermal evaporation under vacuum of 1.33 × 10^-4 Pa （ 10^-6 Torr） on unheated glass substrates. The effect of thickness on the structural, morphological and optical properties of SnSb2S4 thin films was investigated. Films thickness measured by interference fringes method varied from 50 to 700 nm. X-ray diffraction analysis revealed that all the SnSb2S4 films were polycrystalline in spite without heating the substrates and the crystallinity was improved with increasing film thickness. The microstructure parameters： crystallite size, strain and dislocation density were calculated. It was observed that the crystallite size increased and the crystal defects decreased with increasing film thickness. In addition, by increasing the film thickness, an enhancement in the surface roughness root-mean-square （RmS） increased from 2.0 to 6.6 nm. The fundamental optical parameters like band gap, absorption and extinction coefficient were calculated in the strong absorption region of transmittance and reflectance spectrum. The optical absorption measurements indicated that the band （eg） gap of the thin films decreased from 2.10 to 1.65 eV with increasing film thickness. The refractive indexes were evaluated in transparent region in terms of envelope method, which was suggested by Swanepoul. It was observed that the refractive index increased with increasing film thickness.

关键词： Ternary system Thermal evaporation technique Thin films Thickness Atomic force microscopy (AFm)

ABA and GA_(3)affect the growth and pigment composition in Andrographis paniculata *** Nees.,an important folk herb

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Frontiers in Biology 2009年第3期4卷 337-341页

作者： m.GOmATHINAYAGAm V.e.ANURADHA Changxing ZHAO Gloria A.AYOOLA C.Abdul JALeeL R.P.ANNeeRSeLVAm Stress Physiology Lab Department of BotanyAnnamalai UniversityTamil NaduIndia College of Agronomy and Plant Protection Qingdao Agricultural UniversityChunyang RoadChengyang DistrictQingdao 266109China Department of Pharmaceutical Chemistry Faculty of PharmacyUniversity of Lagos CMUL CampusIdi-ArabaLagosNigeria DmJm International(Cansult maunsell/AeCOm Ltd.) Consultant of Gardens Sector ProjectsAlain Municipality and Eastern EmiratesP.O.Box 1419Al-AinAbu DhabiUnited Arab Emirates

In this study,5μmol·L^(-1)abscisic acid(ABA)and gibberellic acid(GA3)were used to study the effect of both growth regulators on the morphological parameters and pigment composition of Andrographis *** growth regulators were applied by means of foliar spray during morning *** treatment inhibited the growth of the stem and internodal length when compared with control,whereas GA3 treatment increased the plant height and internodal *** total number of leaves per plant decreased in the ABA-treated plants,but GA3 treatment increased the total number of leaves when compared with the *** growth regulators(ABA and GA3)showed increased leaf *** and GA3 treatments slightly decreased the total root growth at all the stages of *** growth regulator treatments increased the whole plant fresh and dry weight at all stages of *** enhanced the fresh and dry weight to a larger extent when compared with *** increase in the total chlorophyll content was recorded in ABA and GA3 *** chlorophyll-a,chlorophyll-b,and carotenoids were increased by ABA and GA3 treatments when compared with the control *** xanthophylls and anthocyanin content were increased with ABA and GA3 treatments in *** plants.

关键词： Andrographis paniculata chlorophyll growth xanthophylls anthocyanin carotenoids