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Identification of the Rotor Time Constant in Induction Machines without Speed Sensor

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Identification of the Rotor Time Constant in Induction Machi...

Field scale measurement of greenhouse gas emissions from land applied swine manure

CES/IEEE 5th International Power Electronics and Motion Control Conference

作者： J.n.Chiasson M.Bodson l.M.Tolbert The University of Tennessee ECE Department Knoxville USA The University of Utah ECE Department Salt Lake City USA The University of Tennessee ECE Department Knoxville USA

＜正＞A differential-algebraic method is used to estimate the rotor time constant TR of an induction motor without measurements of the rotor speed/position. The method consists of solving for the roots of a polynomial equation in TR whose coefficients depend only on the stator currents, stator voltages, and their derivatives. Experimental results are presented.

关键词： Rotor Time Constant Sensorless Speed Observer Induction Motor.

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Frontiers of Environmental Science & Engineering 2017年第3期11卷 19-33页

作者： Devin l. Maurer Jacek A. Koziel Kelsey Bruning Department of Agricultural and Biosystems Engineering Iowa State University Ames IA 50011 USA

Greenhouse gas emissions （GhGs） from swine production systems are relatively well researched with the exception of emissions from land application of manure. GttGs inventories are needed for process- based modeling and science-based regulations. Thus, the objective of this observational study was to measure GhG fluxes from land application of swine manure on a typical corn field. Assessment of GhG emissions from deep injected land-applied swine manure, Phil and reapplication in the spring, on a typical US Midwestern corn-on-corn farm was completed. Static chambers were used Ibr flux measurement along with gas analysis on a GC-FID-ECD＋ Measured gas concentrations were used to estimate GhGs flux using four different models： linear regression, nonlinear regression, first order linear regression and the revised hutchinson and Mosier （hMR） model, respectively for *** flux esmnates after manure apphcatmn of 5.85×10 g·ha^-1（1 ha = 0.01 km） of CO2 6.60×10^1g·ha^-1 of Ch4 and3.48 ×10^3g·ha^-1 n2O for the fall trial and 3.11×10^6g·ha^-1 of CO2,2.95×10^3g·ha^-1 of Oh4, and 1.47×10^4g·ha^-1 n2O after the spnng reapphcation trial were observed. The n2O net cumulative flux represents 0.595% of nitrogen applied in swine manure for the fall trial.

关键词： Climate change Emissions Greenhouse gases land application Swine manure

GROWTh PROCESS OF lOW-TEMPERATURE PlASMA-nITRIDInG lAYER On AUSTEnITIC STAInlESS STEEl

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Acta Metallurgica Sinica(English letters) 2004年第2期17卷 210-214页

作者： Z.W.Yu l.Wang X.l.Xu J.B.Qiang DalianMaritimeUniversity Dalian116026China DalianUniversityofTechnology Dalian116026China

The growth process of low-temperaturs plasma-nitriding layer was investigated by scan-ning electron microscopy (SEM) and X-ray diffraction (XRD). The layer is composedof expanded fcc phase (γn), whose lattice parameter of the layer increases with processtime resulting from increasing the nitrogen content. The layer hardness increases grad-ually with nitrogen content. The high slip band density on the layer surface observedin situ by SEM shows that the surface yield occurs when supersaturated nitrogen con-tent in the layer attains to some value, which is also responsible for the increase inlayer hardness.

关键词： austenitic stainless steel plasma nitriding slip band

Aspects of syringeal mechanics in avian phonation

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Aspects of syringeal mechanics in avian phonation

Discharge-Stage Relationship on Urban Streams Evaluated at USGS Gauging Stations,***,Missouri

23rd International Ornithological Congress

作者： Ole n.larsen Franz Goller Johan l.van leeuwen Centre for Sound Communication SDU Odense Univ. DK-5230 Odense Dept. of Biology Univ. of Utah Salt Lake City Utah 84112 USA Dept. of Animal Sciences Wageningen Univ. NL-6709 PG Wageningen The Netherlands

＜正＞ The vocal organ of birds, the syrinx, is formed by modified cartilages of the trachea and/or bronchi and a number of muscles. The syrinx is relatively inaccessible. Although its anatomy, innervation, muscular control, and driving air flow are well described in some species, the biomechanics of phonation are still poorly understood. Recently, the use of very thin, flexible endoscopes has supported prior speculations on syringeal muscle mechanics, since abduction, adduction, rotation, and tensing of syringeal structures in response to

关键词： syrinx endoscopy biomechanics modelling

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Journal of Earth Science 2020年第6期31卷 1133-1141页

作者： Robert E.Criss David l.nelson Department of Earth and Planetary Sciences Washington UniversitySt.Louis MO 63130USA Columbia Cir Pasadena CA 91105USA

Extensive USGS data tables and detailed,1 m2 li DAR surveys are used to determine the optimal power n that relates discharge(Q)to stage(h*)above channel bottom(ho)at 39 gauging stations on small streams in the ***,Missouri area,all of which have catchments of 0.6 to 220 *** different methodologies are employed to determine both n and ho:(1)optimizing linearity in a plot of Q1/n *** stage(hl)using USGS field measurements at each site;(2)optimizing linearity in a plot of Q1/n *** using USGS rating tables at each site;(3)a mathematical inverse method applied to the same USGS rating tables;(4)use of li DAR data on channel geometry to determine the power dependences of channel area A and hydraulic radius h on h*,combined with the Manning and rational equations to predict *** these methods,only methods 2 and 3 compare favorably,and these values compare poorly with Method 1 based on field data,and with method 4 based on theoretical and empirical *** Method 4 is predictive,it provides a useful alternative to methods 1–3 that are based on USGS field measurements,which are heavily weighted toward low *** conclude that the apparent values of n in the USGS rating tables are systematically too low for small streams.

关键词： stream gauging li DAR topography urban flooding discharge hydrology

Prognosis of 148 new Cases of Female Genital Fistula in a Multicentric Study in niger

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Open Journal of Obstetrics and Gynecology 2019年第8期9卷 1197-1201页

作者： n. Idi n. A. harouna Malam Brah A. Idrissa l. Djangnikpo Z. Assoumana FSS Université A Moumouni Niamey Niger Centre national de reference de Fistule obstetricale Niamey Niger UnFPA Niamey Niger

Introduction: We report anatomopathological and treatment results of new cases of obstetrical female genital fistula in main to determine the prognosis. Methodology: Multicentre prospective study over 15 months (January 1st, 2016 to March 31st, 2017) in 5 national centres of female genital fistula treatment. Patients were in all age group. Anatomopathological types were urogenital classified simple, middle and mixte (association of urogenital and recto genital). The methods of treatment were surgery and trans uretral vesical probe. We observed treated patients during 3 months. Results: 148 new cases collected. The study revealed 47.15% of urogenital fistulas were vesico-vaginal and urethro-vaginal (25.71%). 3 cases of rectovaginal fistula including 2 cases in the lower third of the rectum and one in the upper third, 141 patients were treated. The results gave 35 cases treated by trans ureterovesical probe cured and dry, those by surgery were continent and dry (71.62%) but 23 (15.54%) treated but not dry, 12 (4.10%) FGF were not closed tTab5) 7 cases not treated, one referred to urology service, one patient died before treatment and 5 perdu of view. Conclusion: Obstetric fistula remains a serious public health problem in niger. FGF happened in all age old because of non skilled pre- and per-natal care particularly in rural area. Treatment could be improved but political prevention must be the rule.

关键词： FGF Treatment Prognosis niger

Os/γ-Al_2O_3表面上羰基体和甲酸体反应动力学的红外光谱研究

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Chinese Journal of Chemical Physics 1989年第2期2卷 125-134页

作者：伏义路 l.Kraus h.Knozinger 中国科学技术大学近代化学系慕尼黑大学物理化学研究所

基于特定红外吸收带强度的测量,比较了在由K_2[OsO_2(Oh)_4]制得的Os/γ-Al_2O_3催化剂表面上,羰基体和甲酸体同氢或水的反应速率,证明了:1、γ-Al_2O_3表面上Os的存在极大地增进了甲酸体同氢或水的反应活性,这可能是由于氢或水的活化... 详细信息

基于特定红外吸收带强度的测量,比较了在由K_2[OsO_2(Oh)_4]制得的Os/γ-Al_2O_3催化剂表面上,羰基体和甲酸体同氢或水的反应速率,证明了:1、γ-Al_2O_3表面上Os的存在极大地增进了甲酸体同氢或水的反应活性,这可能是由于氢或水的活化吸附造成的.2、473K时,甲酸体同氢的反应比羰基体同氢的反应快,甲酸体反应的产物之一是CO,因而是CO吸附的逆反应。在此温度下CO加氢反应尚未开始进行,故甲酸体看来不是CO加氢反应的中间体。在更高的温度下,这种比较未能实现。3、在低至323K时,甲酸体仍能以相当快的速率同水反应。473K时测得的甲酸体同水的反应速率远比羰基体同水的反应快,以D_2O代替h_2O的同位素替代实验得到了完全相同的结论。因此认为表面甲酸体很可能是变换反应的中间体。

关键词：羰基甲酸反应动力学 Os/r-Ai2O3

PREVEnTIVE EFFECT OF BOROn On DAMAGE TO CARTIlAGE OF RATS WITh InTAKE EXCESSIVE FlUORIDE

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Journal of Pharmaceutical Analysis 2005年第1期17卷 36-39页

作者： Xu P. Guo X. Cao h. Kang l. Du X. Zhang Z. Geng D. Institute of Endemic Diseases Key Laboratory of Environment and Genes Related to Diseases Xi'an Jiaotong University Xi'an 710061 China Institute of Endemic Diseases Medical College of Xi'an Jiaotong University Xi'an 710061 China

Objective: To investigate and analyze the preventive effect of boron on the cartilage damage in rats with intake excessive fluoride. Methods: Fifty-ix Sprague-Dawley rats were divided into the control group (C, intake distilled water), the excessive fluoride dose group (EF, intake distilled water with 100 ppm F-) and the boron prevention group (P, intake distilled water with 100 ppm F- as well as the supplemental boron dietary). 3 to 5 months later, fluorine contents in serum, RnA contents in costal cartilage were assayed. The morphological changes in tibia growth plate cartilage (GPC) in rats were observed. Results: Although exposed to the same dose of fluoride, the fluorine contents in serum in rats of P group decreased notably compared with those of EF group, the damage of tibia GPC under optical and electron microscope lessened significantly, and RnA contents in costal cartilage increased obviously in the 3rd month. Conclusion: Boron added could decrease the fluorine level in the body and relieve the toxic symptom of excess fluoride, and thus boron has a preventive effect on skeletal fluorosis.

关键词： Boron Cartilage Fluoride Prevention Rat

The equilibrium stability for a smooth and discontinuous oscillator with dry friction

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Acta Mechanica Sinica 2016年第2期32卷 309-319页

作者： Zhi-Xin li Qing-Jie Cao Alain léger School of Astronautics Centre for Nonlinear Dynamics Research Harbin Institute of Technology Harbin 150001 China laboratoire de Mecanique et d' Acoustique CNRS 31 Chemin Joseph Aiguier 13402 Marseille Cedex 20 France

In this paper,we investigate the equilibrium stability of a Filippov-type system having multiple stick regions based upon a smooth and discontinuous（SD） oscillator with dry *** sets of equilibrium states of the system are analyzed together with Coulomb friction conditions in both（ f_n,f_s） and（x,˙x） *** the stability analysis,lyapunov functions are constructed to derive the instability for the equilibrium set of the hyperbolic type and la Salle＇s invariance principle is employed to obtain the stability of the nonhyperbolic *** demonstrates the existence of a thick stable manifold and the interior stability of the hyperbolic equilibrium set due to the attractive sliding mode of the Filippov property,and also shows that the unstable manifolds of the hyperbolic-type are that of the endpoints with their saddle *** calculations show a good agreement with the theoretical analysis and an excellent efficien y of the approach for equilibrium states in this particular Filippov ***,the equilibrium bifurcations are presented to demonstrate the transition between the smooth and the discontinuous regimes.

关键词： SD oscillator Equilibrium set Dry friction Coulomb’s cone