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1

DIAGNOSTICO Y ANALISIS DEL IMPACTO DE LOS CASINOS EN EL ECUADOR  

Microsoft Academic Search

En el Ecuador los juegos de azar a diferencia de los países del orbe no es una industria millonaria en la que se jueguen altísimas sumas de dinero, sino más bien es moderado el consumo, así, para 13 millones de habitantes hay 45 casinos de diferente categoría ubicados a lo largo y ancho de las diferentes ciudades del país, los

Autor Alfredo Uquillas

2011-01-01

2

Electrical stator  

SciTech Connect

An electrical stator of an electromagnetic pump includes first and second spaced apart coils each having input and output terminals for carrying electrical current. An elongate electrical connector extends between the first and second coils and has first and second opposite ends. The connector ends include respective slots receiving therein respective ones of the coil terminals to define respective first and second joints. Each of the joints includes a braze filler fixedly joining the connector ends to the respective coil terminals for carrying electrical current therethrough.

Fanning, Alan W. (San Jose, CA); Olich, Eugene E. (Aptos, CA)

1994-01-01

3

Electromagnetic pump stator core  

SciTech Connect

A stator core for supporting an electrical coil includes a plurality of groups of circumferentially abutting flat laminations which collectively form a bore and perimeter. A plurality of wedges are interposed between the groups, with each wedge having an inner edge and a thicker outer edge. The wedge outer edges abut adjacent ones of the groups to provide a continuous path around the perimeter.

Fanning, Alan W. (San Jose, CA); Olich, Eugene E. (Aptos, CA); Dahl, Leslie R. (Livermore, CA)

1995-01-01

4

Banded electromagnetic stator core  

DOEpatents

A stator core for an electromagnetic pump includes a plurality of circumferentially adjoining groups of flat laminations disposed about a common centerline axis and collectively defining a central bore and a discontinuous outer perimeter, with adjacent groups diverging radially outwardly to form V-shaped gaps. An annular band surrounds the groups and is predeterminedly tensioned to clamp together the laminations, and has a predetermined flexibility in a radial direction to form substantially straight bridge sections between the adjacent groups. 5 figs.

Fanning, A.W.; Gonzales, A.A.; Patel, M.R.; Olich, E.E.

1996-06-11

5

Banded electromagnetic stator core  

DOEpatents

A stator core for an electromagnetic pump includes a plurality of circumferentially adjoining groups of flat laminations disposed about a common centerline axis and collectively defining a central bore and a discontinuous outer perimeter, with adjacent groups diverging radially outwardly to form V-shaped gaps. An annular band surrounds the groups and is predeterminedly tensioned to clamp together the laminations, and has a predetermined flexibility in a radial direction to form substantially straight bridge sections between the adjacent groups. 5 figures.

Fanning, A.W.; Gonzales, A.A.; Patel, M.R.; Olich, E.E.

1994-04-05

6

Banded electromagnetic stator core  

DOEpatents

A stator core for an electromagnetic pump includes a plurality of circumferentially adjoining groups of flat laminations disposed about a common centerline axis and collectively defining a central bore and a discontinuous outer perimeter, with adjacent groups diverging radially outwardly to form V-shaped gaps. An annular band surrounds the groups and is predeterminedly tensioned to clamp together the laminations, and has a predetermined flexibility in a radial direction to form substantially straight bridge sections between the adjacent groups.

Fanning, Alan W. (San Jose, CA); Gonzales, Aaron A. (San Jose, CA); Patel, Mahadeo R. (San Jose, CA); Olich, Eugene E. (Aptos, CA)

1994-01-01

7

Banded electromagnetic stator core  

DOEpatents

A stator core for an electromagnetic pump includes a plurality of circumferentially adjoining groups of flat laminations disposed about a common centerline axis and collectively defining a central bore and a discontinuous outer perimeter, with adjacent groups diverging radially outwardly to form V-shaped gaps. An annular band surrounds the groups and is predeterminedly tensioned to clamp together the laminations, and has a predetermined flexibility in a radial direction to form substantially straight bridge sections between the adjacent groups.

Fanning, Alan W. (San Jose, CA); Gonzales, Aaron A. (San Jose, CA); Patel, Mahadeo R. (San Jose, CA); Olich, Eugene E. (Aptos, CA)

1996-01-01

8

Electromagnetic pump stator core  

SciTech Connect

A stator core for supporting an electrical coil includes a plurality of groups of circumferentially abutting flat laminations which collectively form a bore and perimeter. A plurality of wedges are interposed between the groups, with each wedge having an inner edge and a thicker outer edge. The wedge outer edges abut adjacent ones of the groups to provide a continuous path around the perimeter. 21 figures.

Fanning, A.W.; Olich, E.E.; Dahl, L.R.

1995-01-17

9

Stator rotor tools  

NASA Technical Reports Server (NTRS)

An apparatus and method for removing and reinserting base member segments in an arcuate slot in an engine part are described. Each base member separately includes blades or stators, holding the engine part in place while manipulating fingers or an arm onto an interfitting abutting relationship with most of the blades. A torque force is applied to the base of the blades to move a base member relative to such an arcuate slot.

Diamond, D. D. (inventor)

1978-01-01

10

Electromagnetic pump stator coil  

SciTech Connect

An electrical stator coil for an electromagnetic pump includes a continuous conductor strip having first and second terminals at opposite ends thereof and an intermediate section disposed therebetween. The strip is configured in first and second coil halves, with the first coil half including a plurality of windings extending from the first terminal to the intermediate section, and the second coil half including a plurality of windings extending from the second terminal to the intermediate section. The first and second coil halves are disposed coaxially, and the first and second terminals are disposed radially inwardly therefrom with the intermediate section being disposed radially outwardly therefrom.

Fanning, Alan W. (San Jose, CA); Dahl, Leslie R. (Livermore, CA)

1996-01-01

11

Electromagnetic pump stator coil  

DOEpatents

An electrical stator coil for an electromagnetic pump includes a continuous conductor strip having first and second terminals at opposite ends thereof and an intermediate section disposed therebetween. The strip is configured in first and second coil halves, with the first coil half including a plurality of windings extending from the first terminal to the intermediate section, and the second coil half including a plurality of windings extending from the second terminal to the intermediate section. The first and second coil halves are disposed coaxially, and the first and second terminals are disposed radially inwardly therefrom with the intermediate section being disposed radially outwardly therefrom. 9 figs.

Fanning, A.W.; Dahl, L.R.

1996-06-25

12

Stator Blade Laser Window Research  

NASA Technical Reports Server (NTRS)

All turbofan engines used in modern aviation contain a series of fan blades and compressor blades which are all connected to one drive shaft. Inside the jet engine between each set of blades are stator blades, which are pitched opposite of the fan and compressor blades, the stator blades are both rotational and axial fixed in place. The project that I was assigned to involves the QAT 22 fan test rig; which is currently under final design review and very soon will be fabricated. The purpose of this research facility is to better understand the effects of stator blades. Stator blades are used to straiten the air in a turbine. The researcher's primary aim is to determine what the airflow is like at both the leading edge and the trailing edge of a stator blade. My work focused on designing the windows usable for both a compressor rig and a test fan rig. The difference between the two is the test fan application will be looking into a stator blade array rather than just looking at the rotor. My discussion will include a detailed explanation of how the PIV laser window system functions fiom start to finish. I will also discuss how the information is gathered and organized. Further more I plan to talk about the purpose of this kind of research and the advantages to using this technology to determine the airflow characteristics of blade designs. Finally I will discuss the researcher s conclusion on the relationship between aerodynamics of a blade and how noise is produced. NASA's main goal with this particular facility is find ways to quiet engine noise by reducing the amount of cavitations that occurs around the blades of a turbofan engine. Additional information is included in the original extended abstract.

Lugas, Grant A.

2004-01-01

13

A stator flux oriented induction machine drive  

Microsoft Academic Search

The sensitivity of the parameters of a rotor-flux-oriented system using rotor flux estimation is discussed, and a stator-flux-oriented scheme is developed. Since the estimation of the stator flux is independent of the leakage, the steady-state performance of the stator-flux-oriented system is insensitive to the leakage inductance. A decoupler is designed to minimize the coupling in the stator-flux reference frame, improving

Xingyi Xu; Rik De Doncker; D. W. Novotny

1988-01-01

14

Stator having selectively applied thermal conductivity coating  

Microsoft Academic Search

This patent describes a gas turbine engine stator for surrounding a rotor including a plurality of circumferentially spaced blades, each having a tip. It comprises a stator flowpath surface adjacent and around the rotor blade tips to define a radial clearance therebetween; and means for controlling non-axisymmetric radial clearance which occurs between the stator flowpath surface and the blade tips.

L. W. Plemmons; W. C. Oakes; R. A. Kirkpatrick

1992-01-01

15

Automated robotic inspection of large generator stators  

Microsoft Academic Search

The non-destructive inspection of large-generator stators is a repetitive and time-consuming task, ideal to be performed by a robot. This paper describes the design and implementation of such a device, conceived to inspect all stator bars and stator winding slots, with the rotor removed from the generator. The inspection requirements as well as the realized robotic solution are presented. The

Roland Moser; Bernhard Mark

2007-01-01

16

Analytical and experimental investigation of stator endwall contouring in a small axial-flow turbine. 1: Stator performance  

NASA Technical Reports Server (NTRS)

Three stator configurations were studied to determine the effect of stator outer endwall contouring on stator performance. One configuration was a cylindrical stator design. One contoured stator configuration had an S-shaped outer endwall, the other had a conical-convergent outer endwall. The experimental investigation consisted of annular surveys of stator exit total pressure and flow angle for each stator configuration over a range of stator pressure ratio. Radial variations in stator loss and aftermixed flow conditions were obtained when these data were compared with the analytical results to assess the validity of the analysis, good agreement was found.

Haas, J. E.

1982-01-01

17

Stators with improved conductor assembly and method of making same  

DOEpatents

A stator includes a stator core, a plurality of slots, and a conductor. The plurality of slots are formed within the stator core. The conductor is disposed continuously within at least two of the plurality of openings.

Dang, Dang Dinh; Blissenbach, Rolf; Schauer, David; Wattleworth, John; Milani, Michael; Hatch, Erik

2013-07-30

18

Study of controlled diffusion stator blading  

NASA Technical Reports Server (NTRS)

Tests were conducted on a high tip speed, highly loaded front compressor stage having low aspect ratio rotor and stator airfoils. The stator airfoils were designed by the controlled diffusion procedure recently developed by P&WA for designing transonic cascade airfoils. The rotor blades consisted of multiple-circular-arc airfoil sections. The stage had a tip speed of 442 m/sec (1450 ft/sec), a hub/tip ratio of 0.597, a rotor aspect ratio of 1.3, and a stator aspect ratio of 1.45. At design speed the rotor-stator stage achieved an adiabatic efficiency of 89.1% at design flow and pressure ratio. Surge margin was 14%. The stage efficiency exceeded the design goal by 0.6 percentage points. The rotor efficiency was 92.4%, exceeding design by 0.3 percentage points. The controlled diffusion stator demonstrated a lower minimum loss over the multiple-circular-arc stator from the root to 70 percent span. A surge diffusion factor of 0.72 was reached at both the rotor tip and the stator root. The NAS3-22008 program demonstrated its intent: high efficiency and loading levels with low aspect ratio blades and the controlled diffusion stator in the unfavorable front stage environment.

Behlke, R. F.; Brooky, J. D.; Canal, E.

1983-01-01

19

NASA gas turbine stator vane ring  

NASA Technical Reports Server (NTRS)

Four monolithic stator vane rings from reaction-bonded silicon nitride were produced. This paper describes the various steps involved: wax injection of stator vane patterns, precise fixturing of patterns, mold fabrication, slip preparation, casting, prenitriding, nitriding, and ceramic machining. Each process step is discussed and illustrated, and tables of property measurements are included.

Gersch, H. M.

1981-01-01

20

Fundamental Investigation of Circumferentially Varying Stator Cascades  

NASA Astrophysics Data System (ADS)

The fundamentals of circumferentially varying stator cascades and their interactions with a downstream fixed pitch propeller were investigated experimentally utilizing multiple measurement techniques. The flow physics associated with the isolated circumferentially varying, or cyclic, stator cascade was studied in a wind tunnel environment through string tuft flow visualization, 2-D PIV, Stereoscopic PIV, and static surface pressure measurements. The coupled wake physics of the cyclic stator cascade with propeller were then investigated in a water tunnel using Stereo PIV. Finally, the global performance of components and the coupled system were quantified through force and moment measurements on the model in the water tunnel. A cyclic distribution of the stators' deflections resulted in non-axisymmetric distributions of the surface pressure and the flow field downstream of the stator array. In the model near wake the flow field is associated with secondary flow patterns in the form of coherent streamwise vortical structures that can be described by potential flow mechanisms. The collective pitch distribution of the stators produces a flow field that resembles a potential Rankine vortex, whereas the cyclic pitch distribution generates a flow pattern that can be described by a potential vortex pair in a cross flow. The stator distribution alone produces a significant side force that increases linearly with stator pitch amplitude. When a propeller is incorporated downstream from the cyclic cascade the side force from the stator cascade is reduced, but a small vertical force and pitching moment are created. The generation of these secondary forces and moments can be related to the redistribution of the tangential flow from the cyclic cascade into the axial direction by the retreating and advancing blade states of the fixed pitch propeller.

Farnsworth, John A. N.

21

A study of unsteady rotor-stator interactions  

Microsoft Academic Search

The rotor-generated unsteady response of the turbulent flow in a stator is simulated using a simplified situation of the flow between two parallel plates to represent flow between the stator blades; the rotor's effect is represented by moving cylinders of equivalent drag coefficient that produce passing wakes at the entrance of the stator. Results indicate that the wake passing produces

Reda R. Mankbadi

1989-01-01

22

Thrust force calculation of LSM with asymmetric long stator  

Microsoft Academic Search

At curve section of track of long stator linear synchronous motors (LSM) for maglev train, the stators are asymmetric to compensate the distance difference between inner and outer tracks. In this paper, we calculate motor's flux density in suspension gap between stator and magnet, and then the thrust force of asymmetric LSM under different track-gap is described. The force loss

Fei Liu; Liming Shi; Yaohua Li

2009-01-01

23

Research and optimization on stator curve for roller pump  

NASA Astrophysics Data System (ADS)

By analyzing the advantages and disadvantages of common roller pump's stator curve (assuming that the roller on this stator curve has eliminated the void point), using curve fitting transitional method to pass the soft and hard impact point, then we can obtain a high order stator curve which has lower noise. By creating a smooth stator curve (and an inflection point with a common tangent) radial velocity mutation is eliminated. In order to avoid radial velocity mutation a symmetrical radial acceleration curve is used. In order to eliminate radial acceleration mutation, both ends of the radial acceleration change rate curve are valued zero. The results showed that due to the catastrophe point of the roller's stator curve, improving its stator curve eliminates the void point and the soft and hard impact point of the roller on the stator transitional curve. Compare the eighth-power stator curve with the improved stator curve, the improved curve also has the same superior performance. On the improved stator curve, the flow pulsation could be decreased by 241.39mL/min, with which the abrasion of the roller, the impact of the pump and the noise of the pump can be reduced.

Yang, G. L.; Zhang, J. F.; Su, H. S.; Zhang, L. Q.

2013-12-01

24

Reconstruction of the Switched Reluctance Motor Stator  

NASA Astrophysics Data System (ADS)

The paper re-designs the conventional 6/8 switched reluctance motor (SRM) by a particular way to minimize the losses. The flux loops are shortened by making each two stator teeth incorporated in one magnetic circuit only. Subsequently the flux does not cross in some iron parts of the stator core backs. These unused iron sections are taken off consequently the iron losses decreased. Now the stator consists of three separated sections and they are fixed inside non-magnetic cylinder. The copper losses also are decreased because less copper windings are used to produce the same amount of the output torque as the flux paths become short then the flux density increases. The analysis and comparison of the 6/8 SRM before and after the re-design process are presented. A m files Matlab software is used to simulate the dynamic performance. Then the paper proceeds to examine different control techniques to the new design. The hysteresis and PI controllers are used as classical method to control the SRM. Then the artificial neural network (ANN) is used to test the new control techniques.

El-Kharashi, Eyhab; Hassanien, Hany M.

2012-01-01

25

Benefits of Swept and Leaned Stators for Fan Noise Reduction  

NASA Technical Reports Server (NTRS)

An advanced high bypass ratio fan model was tested in the NASA Lewis Research Center 9 x 15-Foot Low Speed Wind Tunnel. The primary focus of this test was to quantify the acoustic benefits and aerodynamic performance of sweep and lean in stator vane design. Three stator sets were used for this test series. A conventional radial stator was tested at two rotor-stator axial spacings. Additional stator sets incorporating sweep + lean, and sweep only were also tested. The hub axial location for the swept + lean, and sweep only stators corresponded to the location of the radial stator at the upstream rotor-stator spacing, while the tip axial location of these modified stators corresponded to the radial stator axial position at the downstream position. The acoustic results show significant reductions in both rotor-stator interaction noise and broadband noise beyond what could be achieved through increased axial spacing of the conventional, radial stator. Theoretical application of these results to acoustically quantify a fictitious 2-engine aircraft and flight path suggested that about 3 Effective Perceived Noise (EPN) dB could be achieved through incorporation of these modified stators. This reduction would represent a significant portion of the 6 EPNdB noise goal of the current NASA Advanced Subsonic Technology (AST) initiative relative to that of 1992 technology levels. A secondary result of this fan test was to demonstrate the ability of an acoustic barrier wall to block aft-radiated fan noise in the wind tunnel, thus revealing the acoustic structure of the residual inlet-radiated noise. This technology should prove valuable toward better understanding inlet liner design, or wherever it is desirable to eliminate aft-radiated noise from the fan acoustic signature.

Woodward, Richard P.; Elliott, David M.; Hughes, Christopher E.; Berton, Jeffrey J.

1998-01-01

26

Evaluation of ceramics for stator application: Gas turbine engine report  

NASA Technical Reports Server (NTRS)

Current ceramic materials, component fabrication processes, and reliability prediction capability for ceramic stators in an automotive gas turbine engine environment are assessed. Simulated engine duty cycle testing of stators conducted at temperatures up to 1093 C is discussed. Materials evaluated are SiC and Si3N4 fabricated from two near-net-shape processes: slip casting and injection molding. Stators for durability cycle evaluation and test specimens for material property characterization, and reliability prediction model prepared to predict stator performance in the simulated engine environment are considered. The status and description of the work performed for the reliability prediction modeling, stator fabrication, material property characterization, and ceramic stator evaluation efforts are reported.

Trela, W.; Havstad, P. H.

1978-01-01

27

Diagnostico de Prenez en Ganado Vacuno.  

E-print Network

Becerros logrados (por 100 vacas) 550' 500 450 400 350 1 90 19.2 21.1 23.5 26.4 30.2 330 300 270 240 21 0 60 28.8 31.7 35.2 39.6 45.2 'Los nlimeros de arriba indican libras de becerro producido por vaca. CARUNCULAS \\ VULVA Figura 2. Anatornia del... Becerros logrados (por 100 vacas) 550' 500 450 400 350 1 90 19.2 21.1 23.5 26.4 30.2 330 300 270 240 21 0 60 28.8 31.7 35.2 39.6 45.2 'Los nlimeros de arriba indican libras de becerro producido por vaca. CARUNCULAS \\ VULVA Figura 2. Anatornia del...

Sorensen, A. M. Jr.; Beverly, J. R.; Arias, A. A.

1975-01-01

28

Generator stator core vent duct spacer posts  

DOEpatents

Generator stator cores are constructed by stacking many layers of magnetic laminations. Ventilation ducts may be inserted between these layers by inserting spacers into the core stack. The ventilation ducts allow for the passage of cooling gas through the core during operation. The spacers or spacer posts are positioned between groups of the magnetic laminations to define the ventilation ducts. The spacer posts are secured with longitudinal axes thereof substantially parallel to the core axis. With this structure, core tightness can be assured while maximizing ventilation duct cross section for gas flow and minimizing magnetic loss in the spacers.

Griffith, John Wesley (Schenectady, NY); Tong, Wei (Clifton Park, NY)

2003-06-24

29

Test of a CMC liquid propulsion rocket engine turbine stator  

Microsoft Academic Search

The succesful testing of two Ceramic Matrix Composite (CMC) stators in conditions fully representative of a cryogenic rocket engine turbine is reported. Both stators possessed the same overall geometry as the actual metallic component used in the turbine second stage of the HM7 engine. They sustained several mid duration tests devoted to combustion parameter tuning and composite material behavior control,

J. Berque; J. M. Georges

1992-01-01

30

Modeling shrouded stator cavity flows in axial-flow compressors  

Microsoft Academic Search

Experiments and computational analyses were completed to understand the nature of shrouded stator cavity flows. From this understanding, a one-dimensional model of the flow through shrouded stator cavities was developed. This model estimates the leakage mass flow, temperature rise, and angular momentum increase through the cavity, given geometry parameters and the flow conditions at the interface between the cavity and

S. R. Wellborn; I. Tolchinsky; T. H. Okiishi

2000-01-01

31

Turbine rotor/stator flowfield analysis  

NASA Technical Reports Server (NTRS)

A numerical study of the unsteady aerodynamic and thermal environment associated with axial turbine stages is presented. Computations are performed using a modification of the ROTOR1 rotor/stator interaction code. Two different turbine states are analyzed: the first state of the United Technologies Research Center large scale rotating rig and the first state of the Space Shuttle main engine (SSME) high pressure fuel turbopump. Time-averaged blade midspan pressure and heat transfer profiles are calculated using the following different surface boundary conditions: adiabatic wall, prescribed wall temperature, and prescribed heat flux. Numerical solutions for the large scale rotating rig are compared with experimental data. Unsteady pressure envelopes are also presented for each geometry. In addition, instantaneous contours are plotted for the SSME configuration.

Griffin, Lisa

1989-01-01

32

Ceramic-to-metal stator vane assembly with braze  

DOEpatents

A stator vane assembly for a gas turbine engine that includes a plurality of circumferentially spaced ceramic vanes, each of which has an inner and outer ceramic shroud, and a ceramic post extending from one of the shrouds, and a metallic platform having a plurality of circumferentially spaced recesses. The posts are inserted into a metallic sleeve and then brazed. The brazed sleeves are then mounted in the recesses. A method for assembling these components to form the stator assembly is also described.

Chase, Donna J. (Scottsdale, AZ); Fang, Ho T. (Scottsdale, AZ); Irwin, Craig W. (Tempe, AZ); Schienle, James L. (Phoenix, AZ)

1995-01-01

33

Experimental investigation of steady and unsteady flow field downstream of an automotive torque converter turbine and inside the stator. Part 2: Unsteady pressure on the stator blade surface  

Microsoft Academic Search

The stator flow field of an automotive torque converter is highly unsteady due to potential and viscous interactions with upstream and downstream rotors. The objective of this investigation is to understand the influence of potential and viscous interactions of the upstream rotor on the stator surface pressure field with a view toward improvement of the stator design. Five miniature fast-response

B. V. Marathe; B. Lakshminarayana; D. G. Maddock

1997-01-01

34

Dynamics of the bacterial flagellar motor with multiple stators  

E-print Network

The bacterial flagellar motor drives the rotation of flagellar filaments and enables many species of bacteria to swim. Torque is generated by interaction of stator units, anchored to the peptidoglycan cell wall, with the rotor. Recent experiments [Yuan, J. & Berg, H. C. (2008) PNAS 105, 1182-1185] show that near zero load the speed of the motor is independent of the number of stators. Here, we introduce a mathematical model of the motor dynamics that explains this behavior based on a general assumption that the stepping rate of a stator depends on the torque exerted by the stator on the rotor. We find that the motor dynamics can be characterized by two time scales: the moving-time interval for the mechanical rotation of the rotor and the waiting-time interval determined by the chemical transitions of the stators. We show that these two time scales depend differently on the load, and that their crossover provides the microscopic explanation for the existence of two regimes in the torque-speed curves observed experimentally. We also analyze the speed fluctuation for a single motor using our model. We show that the motion is smoothed by having more stator units. However, the mechanism for such fluctuation reduction is different depending on the load. We predict that the speed fluctuation is determined by the number of steps per revolution only at low load and is controlled by external noise for high load. Our model can be generalized to study other molecular motor systems with multiple power-generating units.

G. Meacci; Y. Tu

2009-01-07

35

High-order Large Eddy Simulations of Confined Rotor-Stator Flows  

E-print Network

1 High-order Large Eddy Simulations of Confined Rotor-Stator Flows S. Viazzo*, S. Poncet, E. Serre applications, the investigation of rotating turbulent flow is of great interest. In rotor-stator cavities-order LES methods to predict a turbulent rotor-stator flow at the rotational Reynolds number Re(= b�/)=4

Boyer, Edmond

36

Comparative analysis of stator iron core damage using nominal and reduced flux  

Microsoft Academic Search

Good quality of insulation between stator iron laminations is one of the major preconditions for proper operation and top performance of generating units. Local hot spots and overheating as a result of insufficient insulation between stator iron laminations, beside the other problems, will cause premature aging of high voltage insulation in stator bars. This type of test can be done

M. Gavric; M. Senjamin; M. Kotlica

1999-01-01

37

Aeropropulsion Technology (APT). Task 23 - Stator Seal Cavity Flow Investigation  

NASA Technical Reports Server (NTRS)

The focus of NASA Contract NAS3-25950 Task 23 was to numerically investigate the flow through an axial compressor inner-banded stator seal cavity. The Allison/NASA developed ADPAC code was used to obtain all flow predictions. Flow through a labyrinth stator seal cavity of a high-speed compressor was modeled by coupling the cavity flow path and the main flow path of the compressor. A grid resolution study was performed to guarantee adequate grid spacing was used. Both unsteady rotor-stator-rotor interactions and steady-state isolated blade calculations were performed with and without the seal cavity present. A parameterized seal cavity study of the high-speed stator seal cavity collected a series of solutions for geometric variations. The parameter list included seal tooth gap, cavity depth, wheel speed, radial mismatch of hub flowpath, axial trench gap, hub corner treatments, and land edge treatments. Solution data presented includes radial and pitchwise distributions of flow variables and particle traces describing the flow character.

Heidegger, N. J.; Hall, E. J.; Delaney, R. A.

1996-01-01

38

Stator current demodulation for induction machine rotor faults diagnosis  

E-print Network

and Park transform for dynamic rotor faults (broken or cracked rotor bars and dynamic rotor eccentricityStator current demodulation for induction machine rotor faults diagnosis El Houssin El Bouchikhi--Several studies have demonstrated that induction machine faults introduce phase and/or amplitude modulation

Boyer, Edmond

39

Nickel base alloy. [for gas turbine engine stator vanes  

NASA Technical Reports Server (NTRS)

A nickel base superalloy for use at temperatures of 2000 F (1095 C) to 2200 F (1205 C) was developed for use as stator vane material in advanced gas turbine engines. The alloy has a nominal composition in weight percent of 16 tungsten, 7 aluminum, 1 molybdenum, 2 columbium, 0.3 zirconium, 0.2 carbon and the balance nickel.

Freche, J. C.; Waters, W. J. (inventors)

1977-01-01

40

Electromagnetic pump stator frame having power crossover struts  

DOEpatents

A stator frame for an electromagnetic pump includes a casing joined to a hub by a plurality of circumferentially spaced apart struts. At least one electrically insulated power crossover lead extends through the hub, through a crossover one of the struts, and through the casing for carrying electrical current therethrough.

Fanning, Alan W. (San Jose, CA); Olich, Eugene E. (Aptos, CA)

1995-01-01

41

Decarburisation of interlocked and laser welded stator and rotor cores  

NASA Astrophysics Data System (ADS)

Assembled rotor and stator cores were annealed in an industrial furnace. The final carbon content of the annealed cores was identical, irrespective of the position of the lamination in the assembled core, the initial carbon content or the geometry of the laminations. It is concluded that it is not necessary to use pre-decarburised semi processed electrical steels for automatic assembly.

Standaert, C.; Eloot, K.; De Paepe, A.; Wokowski, P.

1996-07-01

42

Stator winding leakage inductances determination using finite elements method  

Microsoft Academic Search

This paper presents a new method to establish the leakage inductances of AC machine stator winding using a numerical analyzing program based on the finite elements method. The 3D numerical analysis is used to determine the end winding leakage inductance. In order to eliminate the magnetic flux present in the space normally occupied by the rotor, when the rotor is

O. Chiver; E. Micu; C. Barz

2008-01-01

43

Low power stator core fault testing using EL CID  

Microsoft Academic Search

Generator stators are made from thin laminations with interlaminar insulation, defects in which permit damaging currents to flow. Traditional test methods require a substantial supply to excite the core at rated magnetic flux, temperature rises due to faults being detected by various means. The test is performed with the rotor removed and requires significant time and labour. The alternative low

D. B. Paley

1998-01-01

44

Rotor to stator contacts in turbomachines. Review and application  

NASA Astrophysics Data System (ADS)

The safety of turbomachines requires controlling the risks caused by contacts occurring between fixed and rotating parts. Undesirable phenomena induced by bladed wheel/casing interactions are caused by the forced excitation of the natural modes of a blade leading to its damage or by potentially dangerous couplings between the modes of the casing and those of the wheel. Rotor-stator contacts may also lead to various types of dangerous behavior, including the well known configurations of dry whirl and dry whip. The paper proposes a large-scale literature review and examines existing numerical models and experimental setups used for highlighting the phenomenology involved in different rotor to stator contacts configurations. It confirms the great complexity of the problems which, by nature, are considerably nonlinear and involve multiphysics and multiscale coupled behaviors.

Jacquet-Richardet, G.; Torkhani, M.; Cartraud, P.; Thouverez, F.; Nouri Baranger, T.; Herran, M.; Gibert, C.; Baguet, S.; Almeida, P.; Peletan, L.

2013-11-01

45

Test of a CMC liquid propulsion rocket engine turbine stator  

NASA Astrophysics Data System (ADS)

The succesful testing of two Ceramic Matrix Composite (CMC) stators in conditions fully representative of a cryogenic rocket engine turbine is reported. Both stators possessed the same overall geometry as the actual metallic component used in the turbine second stage of the HM7 engine. They sustained several mid duration tests devoted to combustion parameter tuning and composite material behavior control, before long duration runs, representative of the engine duty cycle. The main objectives were to increase the gas temperature above 1600 K, and to simulate the thermal shock that occurs during the chilldown at the end of the combustion phase, in order to provide a good insight of the benefits in terms of performance, mass, durability and reliability associated with CMC application to a large set of aerospace engine turbines.

Berque, J.; Georges, J. M.

46

Test of a CMC liquid propulsion rocket engine turbine stator  

NASA Astrophysics Data System (ADS)

During the first semester of 1991, SEP successfully tested two Ceramic Matrix Composite stators in conditions fully representative of a cryogenic rocket engine turbine. Both stators possessed the same overall geometry as the actual metallic component used in the turbine second stage of the HM7 engine. They sustained several mid-duration tests devoted to combustion parameter tuning and composite material behavior control, before long duration runs, representative of the engine duty cycle. The main objectives were to increase the gas temperature above 1600 K, and to simulate the thermal shock that occurs during the chilldown at the end of the combustion phase, in order to provide a good insight of the benefits in terms of performance, mass, durability and reliability associated with CMC application to a large set of aerospace engine turbines.

Berque, J.; Georges, J. M.

1992-07-01

47

Rotor and stator assembly configured as an aspirating face seal  

NASA Technical Reports Server (NTRS)

A rotor and stator assembly having a rotor and a stator with opposing surfaces defining an air bearing and an air dam of an aspirating face seal. In a first embodiment, the air bearing and the air dam are axially offset. In a second embodiment, the rotor has an axially extending protuberance located radially between the air bearing and the air dam. The axial offset and the protuberance each act to divert the air flow (e.g., compressed gas or combustion gases in a gas turbine or steam in a steam turbine) in a direction transverse to the air flow direction through the air bearing and the air dam, thus isolating the air flows from the air bearing and the air dam which improves seal performance.

Turnquist, Norman Arnold (Inventor); Bagepalli, Bharat Sampathkumaran (Inventor); Reluzco, George (Inventor); Tseng, Wu-Yang (Inventor)

1999-01-01

48

Stator Loading Measurements Behind a Fan With Trailing Edge Blowing  

NASA Technical Reports Server (NTRS)

The problem of aircraft noise pollution around airports has become increasingly important as those areas have become more densely populated. Currently, the removal of older noisier aircraft from operation is reducing noise levels around airports; however, with air traffic projected to increase by about 5% over the next decade the number of commercial aircraft operating in the world is expected to be about 17,700 by the year 2007. To keep noise levels around airports from increasing as a result of traffic increases, it is important to investigate new methods of noise reduction. The objective of this work is to provide a better understanding of the effects that trailing edge blowing has on stator unsteady loading. This is done by presenting flowfield and stator loading data from experiments conducted with and without trailing edge blowing.

Waitz, Ian A.

2000-01-01

49

Frequency Domain Analysis in Rotor\\/Stator Contact Problems  

Microsoft Academic Search

There are a variety of abnormal running conditions in rotating machinery which lead to rotor\\/stator dynamics interactions which, in turn, can cause a rich mixture of eects asso- ciated with rub-related phenomena. These eects manifest themselves in the occurrence of multiple solutions for steady-state vibration response scenarios, including amplitude jumps during rotor acceleration, and vibration responses at dierent\\/multiple frequencies of

Gotz von Groll; David J Ewins

2000-01-01

50

Detection of stator core faults in large turbo-generators  

Microsoft Academic Search

Many large turbo-generators today are now operating beyond their design lifetime, with careful condition-based maintenance and operation having extended their life expectancy. Monitoring the health of large turbo-generators is now an integral part of their operation. This paper describes the use of non-invasive electromagnetic sensors to detect core inter-lamination insulation faults in the stator cores of large turbo-generators before they

A. C. Smith; D. Bertenshaw; C. W. Ho; T. Chan; M. Sasic

2009-01-01

51

SPEEDAM, 8-10 June 1994, Taormina (Italy), pp.145-149 Influence of Stator Yoke Thickness and Stator Teeth Shape upon  

E-print Network

Teeth Shape upon Ripple and Average Torque of Switched Reluctance Motors E. HOANG, B. MULTON, R. VIVES: - the thickness of the stator yoke; - the shape of stator teeth. In keeping the other geometrical parameters, like teeth (see Fig. 1). The use of a 2-D. finite-element software is essential for taking equations which

Paris-Sud XI, Université de

52

INCUBACION ANAEROBICA DEL SUELO COMO DIAGNOSTICO DE LA RESPUESTA A NITROGENO DEL MAIZ BAJO SIEMBRA DIRECTA  

Microsoft Academic Search

-1 then the yield increment = 72,5 - 1,38 Nan, if Nan > 48.mg kg -1 the yield increment = 6 %). Nan was related with the time (years) since the last pasture (r 2 = 0.39). These results suggest that Nan probably is associated with light carbon fractions and can be used to explain the response of maize to

PA CALVIÑO; HE ECHEVERRÍA

53

Diagnostico de las Fuentes No convenionales de Energía en Colombia  

Microsoft Academic Search

El dicumento considera ejes transversales y ejes verticales. Los primeros están relacionados con aspectos que conciernen a todas las FNCE como son el marco legal y regulatorio, y los aspectos ambientales de las FNCE. A continuación se desarrollan ejes verticales, uno por cada fuente. El capítulo 2 hace una revisión y análisis del marco institucional, de política y regulatorio. Plantea

Ernesto Torres; José Maria Rincón; Edinson Lozano

2011-01-01

54

Modeling shrouded stator cavity flows in axial-flow compressors  

SciTech Connect

Experiments and computational analyses were completed to understand the nature of shrouded stator cavity flows. From this understanding, a one-dimensional model of the flow through shrouded stator cavities was developed. This model estimates the leakage mass flow, temperature rise, and angular momentum increase through the cavity, given geometry parameters and the flow conditions at the interface between the cavity and primary flow path. This cavity model consists of two components, one that estimates the flow characteristics through the labyrinth seals and the other that predicts the transfer of momentum due to windage. A description of the one-dimensional model is given. The incorporation and use of the one-dimensional model in a multistage compressor primary flow analysis tool is described. The combination of this model and the primary flow solver was used to reliably simulate the significant impact on performance of the increase of hub seal leakage in a twelve-stage axial-flow compressor. Observed higher temperatures of the hub region fluid, different stage matching, and lower overall efficiencies and core flow than expected could be correctly linked to increased hub seal clearance with this new technique. The importance of including these leakage flows in compressor simulations is shown.

Wellborn, S.R.; Tolchinsky, I.; Okiishi, T.H.

2000-01-01

55

Rail stator augmentation magnetic flux compression linear generator used in electric guns  

Microsoft Academic Search

In order to find an applicable power supply used in electric guns, there have been two types of the magnetic flux compression linear generator (MFCLG) that use the solenoids as the stators. That is to say, a piston armature or a solenoid armature is used within the stator. Although they can amplify the current theoretically, they can only compress the

Xiaojun Duan; Zhengguo Liu; Xiang Li; Ying Wang; Zhiyuan Li

2005-01-01

56

Noise produced by the interaction of a rotor wake with a swept stator blade  

Microsoft Academic Search

An analysis is developed for the noise generated by the interaction of rotor viscous wakes and a single swept stator vane. The stator vane spans a channel with infinite parallel walls which contains a uniform subsonic mean flow. High frequency wakes, for which the noise generation is concentrated at the vane leading edge, are considered. The general wake pattern is

E. Envia; E. J. Kerschen

1984-01-01

57

Superconducting electromechanical rotating device having a liquid-cooled, potted, one layer stator winding  

DOEpatents

A superconducting electromechanical rotating (SER) device, such as a synchronous AC motor, includes a superconducting field winding and a one-layer stator winding that may be water-cooled. The stator winding is potted to a support such as the inner radial surface of a support structure and, accordingly, lacks hangers or other mechanical fasteners that otherwise would complicate stator assembly and require the provision of an unnecessarily large gap between adjacent stator coil sections. The one-layer winding topology, resulting in the number of coils being equal to half the number of slots or other mounting locations on the support structure, allows one to minimize or eliminate the gap between the inner radial ends of adjacent straight sections of the stator coilswhile maintaining the gap between the coil knuckles equal to at least the coil width, providing sufficient room for electrical and cooling element configurations and connections. The stator winding may be potted to the support structure or other support, for example, by a one-step VPI process relying on saturation of an absorbent material to fill large gaps in the stator winding or by a two-step process in which small gaps are first filled via a VPI or similar operation and larger gaps are then filled via an operation that utilizes the stator as a portion of an on-site mold.

Dombrovski, Viatcheslav V. (Willoughby Hills, OH); Driscoll, David I. (South Euclid, OH); Shovkhet, Boris A. (Beachwood, OH)

2001-01-01

58

A Review of Results From Thermal Cycling Tests of Hydrogenerator Stator Windings  

Microsoft Academic Search

Thermal cycling of generators, occurring during in- termittent operation of power stations, increases the thermome- chanical stress on the stator groundwall insulation and can, there- fore, contribute to failure of the generator. Thermal cycling stresses can, to some extent, be replicated and accelerated in laboratory tests. Such tests are performed to ascertain whether a new stator winding insulation system can

Maren Istad; Magne Runde; Arne Nysveen

2011-01-01

59

Evidence for Two Flagellar Stators and Their Role in the Motility of Pseudomonas aeruginosa  

Microsoft Academic Search

Pseudomonas aeruginosa is a ubiquitous bacterium capable of twitching, swimming, and swarming motility. In this study, we present evidence that P. aeruginosa has two flagellar stators, conserved in all pseudomonads as well as some other gram-negative bacteria. Either stator is sufficient for swimming, but both are necessary for swarming motility under most of the conditions tested, suggesting that these two

Christine M. Toutain; Michael E. Zegans; George A. O'Toole

2005-01-01

60

Models for Bearing Damage Detection in Induction Motors Using Stator Current Monitoring  

Microsoft Academic Search

This paper describes a new analytical model for the influence of rolling-element bearing faults on induction motor stator current. Bearing problems are one major cause for drive failures. Their detection is possible by vibration monitoring of characteristic bearing frequencies. As it is possible to detect other machine faults by monitoring the stator current, a great interest exists in applying the

Martin Blodt; Pierre Granjon; Bertrand Raison; Gilles Rostaing

2008-01-01

61

Bearing damage detection via wavelet packet decomposition of the stator current  

Microsoft Academic Search

Bearing faults are one of the major causes of motor failures. The bearing defects induce vibration, resulting in the modulation of the stator current. In this paper, the stator current is analyzed via wavelet packet decomposition to detect bearing defects. The proposed method enables the analysis of frequency bands that can accommodate the rotational speed dependence of the bearing defect

Levent Eren; Michael J. Devaney

2004-01-01

62

Stator fault analysis based on wavelet technique for wind turbines equipped with DFIG  

Microsoft Academic Search

The paper introduces a monitoring and diagnostic technique for the detection of incipient stator electrical faults in doubly fed induction generators (DFIGs) for wind power systems. Depending on wind speed, the induction machine operates continuously in non stationary conditions. In this context, traditional Fourier Analysis fails to discriminate between healthy and abnormal stator operating conditions. To overcome this limitation a

Y. Gritli; A. Stefani; F. Filippetti; A. Chatti

2009-01-01

63

Stator resistance identification using artificial intelligent technique for the adaptive controller of magnetically saturated induction motor  

Microsoft Academic Search

The problem of controlling the induction motor ?-model with magnetic saturation is considered using an adaptive controller with stator current and rotor speed measurement. The new in this paper that in the previous work, only the rotor resistance and load torque can be adapted using the controller but in this work, using artificial intelligent technique, an adaptation of the stator

Ismail Mohamed Mahmoud

2010-01-01

64

Study on the Vibration Displacement Distribution of a Circular Ultrasonic Motor Stator  

E-print Network

In this paper is presented a theoretical consideration on the stator's displacement distribution, which is one of the most important problems in defining the structure of the circular ultrasonic motor stator. The results are compared with results obtained utilizing holographic interferometer, laser vibrometer and a FEM (finite element method) simulation. They are in a good agreement with each other.

Ri, Chol-Su; Kim, Chol-Su; Im, Song-Jin

2014-01-01

65

Transient analysis of cage induction machines under stator, rotor bar and end ring faults  

Microsoft Academic Search

An analysis method is developed for modeling of multi phase cage induction motors with asymmetry in the stator, arising due to an interturn fault resulting in a disconnection of one or more coils making up a portion of a stator phase winding and any distribution and number of rotor bar and end-ring failures. The approach, based on the winding functions,

Hamid A. Toliyat; T.A. Lipo

1995-01-01

66

Beneé ts of Swept-and-Leaned Stators for Fan Noise Reduction  

Microsoft Academic Search

An advanced high bypass ratio fan model was tested in the NASA John H. Glenn Research Center 9 ££ 15 Foot Low-Speed Wind Tunnel. The primary focus of this test was to quantify the acoustic beneé ts and aerodynamic performance of sweep and lean in stator vanedesign. Three statorsets wereused forthis testseries. Aconventional radial stator set was tested at two

Richard P. Woodward; David M. Elliott; Christopher E. Hughes; Jeffrey J. Berton

2001-01-01

67

Effect of upstream rotor vortical disturbances on the time-averaged performance of axial compressor stators. Part 2: Rotor tip vortex/streamwise vortex-stator blade interactions  

SciTech Connect

In a two-part paper, key computed results from a set of first-of-a-kind numerical simulations on the unsteady interaction of axial compressor stator with upstream rotor wakes and tip leakage vortices are employed to elucidate their impact on the time-averaged performance of the stator. Detailed interrogation of the computed flowfield showed that for both wakes and tip leakage vortices, the impact of these mechanisms can be described on the same physical basis. Specifically, there are two generic mechanisms with significant influence on performance: reversible recovery of the energy in the wakes/tip vortices (beneficial) and the associated nontransitional boundary layer response (detrimental). In the presence of flow unsteadiness associated with rotor wakes and tip vortices, the efficiency of the stator under consideration is higher than that obtained using a mixed-out steady flow approximation. The effects of tip vortices and wakes are of comparable importance. The impact of stator interaction with upstream wakes and vortices depends on the following parameters: axial spacing, loading, and the frequency of wake fluctuations in the rotor frame. At reduced spacing, this impact becomes significant. The most important aspect of the tip vortex is the relative velocity defect and the associated relative total pressure defect, which is perceived by the stator in the same manner as a wake. In Part 2, the focus will be on the interaction of stator with the moving upstream rotor tip and streamwise vortices, the controlling parametric trends, and implications on design.

Valkov, T.V. [Shell International Gas Ltd., London (United Kingdom); Tan, C.S. [Massachusetts Inst. of Tech., Cambridge, MA (United States). Gas Turbine Lab.

1999-07-01

68

Tuning the stator resistance of induction motors using artificial neural network  

SciTech Connect

Tuning the stator resistance of induction motors is very important, especially when it is used to implement direct torque control (DTC) in which the stator resistance is a main parameter. In this paper, an artificial network (ANN) is used to accomplish tuning of the stator resistance of an induction motor. The parallel recursive prediction error and backpropagation training algorithms were used in training the neural network for the simulation and experimental results, respectively. The neural network used to tune the stator resistance was trained on-line, making the DTC strategy more robust and accurate. Simulation results are presented for three different neural-network configurations showing the efficiency of the tuning process. Experimental results were obtained for the one of the three neural-network configuration. Both simulation and experimental results showed that the ANN have tuned the stator resistance in the controller to track actual resistance of the machine.

Cabrera, L.A.; Elbuluk, M.E.; Husain, I. [Univ. of Akron, OH (United States). Dept. of Electrical Engineering] [Univ. of Akron, OH (United States). Dept. of Electrical Engineering

1997-09-01

69

A finite volume method and experimental study of a stator of a piezoelectric traveling wave rotary ultrasonic motor  

E-print Network

A finite volume method and experimental study of a stator of a piezoelectric traveling wave rotary resonance frequency. This paper presents a non-empirical partial differential equations model for the stator is computed and compared to the experimentally-measured operating frequency of the stator of Shinsei USR60

Pugh, Mary

70

Acoustic Benefits of Stator Sweep and Lean for a High Tip Speed Fan  

NASA Technical Reports Server (NTRS)

A model high-speed fan stage was acoustically tested in the NASA Glenn 9- by 15-Foot Low Speed Wind Tunnel at takeoff/approach flight conditions. The fan was designed for a corrected rotor tip speed of 442 m/s (1450 ft/s), and had a powered core, or booster stage, giving the model a nominal bypass ratio of 5. The model also had a simulated engine pylon and nozzle bifurcation contained within the bypass duct. The fan was tested with three stator sets to evaluate acoustic benefits associated with a swept and leaned stator and with a swept integral vane/frame stator which incorporated some of the swept and leaned features as well as eliminated some of the downstream support structure. The baseline fan with the wide chord rotor and baseline stator approximated a current GEAE CF6 engine. A flyover effective perceived noise level (EPNL) code was used to generate relative EPNL values for the various configurations. Flyover effective perceived noise levels (EPNL) were computed from the model data to help project noise benefits. A tone removal study was also performed. The swept and leaned stator showed a 3 EPNdB reduction at lower fan speeds relative to the baseline stator; while the swept integral vane/frame stator showed lowest noise levels at intermediate fan speeds. Removal of the bypass blade passage frequency rotor tone (BPF) showed a 4 EPNdB reduction for the baseline and swept and leaned stators, and a 6 EPNdB reduction for the swept integral vane/ frame stator. Therefore, selective tone removal techniques such as active noise control and/or tuned liner could be particularly effective in reducing noise levels for certain fan speeds.

Woodward, Richard P.; Gazzaniga, John A.; Bartos, Linda J.; Hughes, Christopher E.

2002-01-01

71

Interaction of rotor tip flow irregularities with stator vanes as a noise source  

NASA Technical Reports Server (NTRS)

The role of the interaction of rotor tip flow irregularities (vortices and velocity defects) with downstream stator vanes is discussed as a possible fan noise mechanism. This is accomplished by: (1) indicating some of the mothods of formation of these flow irregularities; (2) observing how they would behave with respect to known noise behavior; and (3) attempting to compare the strength of the rotor tip flow irregularity mechanism with the strength of the more common rotor wake-stator mechanism. The rotor tip flow irregularity-stator interaction is indicated as being a probable inflight noise source.

Dittmar, J. H.

1977-01-01

72

Mathematical Modelling of Induction Motor Transient Processes During Stator Winding Interruption  

NASA Astrophysics Data System (ADS)

This research presents induction motor mathematical model in coordinate axis's ?, ?, which allows to learn transient processes in rotor and stator circuits in the conditions of stator windings opening. Such kind of researches is nowadays actual due to impossibility of main calculated values measuring directly, but only on the stator terminals. Induction motor mathematical model forms Park-Gorev equations in ?, ? coordinate axis. It is preferable to use this coordinate system because it allows comparing the results of mathematical modeling in one of the phases with experimental data without transformations.

Konuhova, Marina; Orlovskis, Guntis; Ketners, Karlis

2010-01-01

73

Surface impedance method applied to the prediction of eddy currents in hydrogenerator stator end regions  

SciTech Connect

A three-dimensional finite-element analysis is employed to investigate the losses of hydrogenerator stator end regions by using surface-impedance boundary conditions. The three-dimensional complexity of the end-winding geometry is fully taken into account by the model. The purpose of this work is also to evaluate the eddy-current paths allowing for slits in the stator teeth and their effectiveness in reducing stator core-end losses. The methodology was applied to the stator core of a 52-pole 300-MVA hydrogenerator in two different cases: (1) with non-slit teeth; (2) with fully slit teeth. It may also be extended to large turbogenerators end regions.

Silva, V.C.; Marechal, Y.; Foggia, A. [URA CNRS 355, Saint-Martin-d`Heres (France). Lab. d`Electrotechnique de Grenoble] [URA CNRS 355, Saint-Martin-d`Heres (France). Lab. d`Electrotechnique de Grenoble

1995-05-01

74

Harmonic control of multiple-stator induction machines for voltage regulation  

E-print Network

Small, one to a few horsepower, three-phase induction machines with three sets of electrically-isolated, magnetically-coupled stator winding circuits are described. A voltage inverter is developed and used to drive one set ...

Holloway, Jack Wade, 1980-

2004-01-01

75

Strength design and reliability evaluation of a hybrid ceramic stator vane for industrial gas turbines  

Microsoft Academic Search

Employing ceramic materials for the critical components of industrial gas turbines is anticipated to improve the thermal efficiency of power plants. We developed a first-stage stator vane for a 1300 C class, 20-MW industrial gas turbine. This stator vane has a hybrid ceramic\\/metal structure, to increase the strength reliability of brittle ceramic parts, and to reduce the amount of cooling

K. Nakakado; T. Machida; H. Miyata; T. Hisamatsu; N. Mori; I. Yuri

1995-01-01

76

Hall effect sensors embedded within two-pole toothless stator assembly  

NASA Technical Reports Server (NTRS)

A two-pole toothless PM machine employs Hall effect sensors to indicate the position of the machine's rotor relative to power windings in the machine's stator. The Hall effect sensors are located in the main magnetic air gap underneath the power windings. The main magnetic air gap is defined by an outer magnetic surface of the rotor and an inner surface of the stator's flux collector ring.

Denk, Joseph (Inventor); Grant, Richard J. (Inventor)

1994-01-01

77

The influence of shrouded stator cavity flows on multistage compressor performance  

Microsoft Academic Search

Experiments were performed on a low-speed multistage axial-flow compressor to assess the effects of shrouded stator cavity flows on aerodynamic performance. Five configurations, which involved systematic changes in seal-tooth leakage rates and\\/or elimination of the shrouded stator cavities, were tested. Rig data indicate increasing seal-tooth leakage substantially degraded compressor performance. For every 1 percent increase in seal-tooth clearance-to-span ratio, the

S. R. Wellborn; T. H. Okiishi

1999-01-01

78

Comparison of stator and rotor induced transients in solid rotor turbine generators  

Microsoft Academic Search

The eddy current distribution arising from stator and rotor decrement tests are calculated in the cross -section of a 333 MVA 4-pole generator. The stator winding is represented by an equivalent current sheet, voltages in it being calculated from a two-axis consideration of the air-gap field, Coupling equations for the field in the machine and the windings are formulated with

A. Hannalla; D. MacDonald

1979-01-01

79

Applicable dimensioning and measure and technological examination of long stator-linear motors for magnetic high-speed railways  

NASA Astrophysics Data System (ADS)

Results of measurements aimed at verification of the characteristic magnitudes of long stator/linear motors are presented. Both TRANSRAPID 06 and 07 vehicles were used for tests and the maximal velocity reached 435 km/h. Stator current and voltage, effective power, efficiency, power factor and electromotive force were measured for all dynamic states of the vehicle: acceleration, inertial cruise and braking. The results were discussed in the case of perturbations and incidents of the linear motor, such as electrical short circuits in the long stator winding. Requirements for dimensioning the linear motor were identified and the influence of stator and excitation parameters on the curve electromotive force versus velocity was estimated.

Fuerst, Ruediger

80

Effects of Shrouded Stator Cavity Flows on Multistage Axial Compressor Aerodynamic Performance  

NASA Technical Reports Server (NTRS)

Experiments were performed on a low-speed multistage axial-flow compressor to assess the effects of shrouded stator cavity flows on aerodynamic performance. Five configurations, which involved changes in seal-tooth leakage rates and/or elimination of the shrouded stator cavities, were tested. Data collected enabled differences in overall individual stage and the third stage blade element performance parameters to be compared. The results show conclusively that seal-tooth leakage ran have a large impact on compressor aerodynamic performance while the presence of the shrouded stator cavities alone seemed to have little influence. Overall performance data revealed that for every 1% increase in the seal-tooth clearance to blade-height ratio the pressure rise dropped up to 3% while efficiency was reduced by 1 to 1.5 points. These observed efficiency penalty slopes are comparable to those commonly reported for rotor and cantilevered stator tip clearance variations. Therefore, it appears that in order to correctly predict overall performance it is equally important to account for the effects of seal-tooth leakage as it is to include the influence of tip clearance flows. Third stage blade element performance data suggested that the performance degradation observed when leakage was increased was brought about in two distinct ways. First, increasing seal-tooth leakage directly spoiled the near hub performance of the stator row in which leakage occurred. Second, the altered stator exit now conditions caused by increased leakage impaired the performance of the next downstream stage by decreasing the work input of the downstream rotor and increasing total pressure loss of the downstream stator. These trends caused downstream stages to progressively perform worse. Other measurements were acquired to determine spatial and temporal flow field variations within the up-and-downstream shrouded stator cavities. Flow within the cavities involved low momentum fluid traveling primarily in the circumferential direction at about 40% of the hub wheel speed. Measurements indicated that the flow within both cavities was much more complex than first envisioned. A vortical flow structure in the meridional plane, similar to a driven cavity, existed within the upstream cavity Furthermore, other spatial and temporal variations in Row properties existed. the most prominent being caused by the upstream potential influence of the downstream blade. This influence caused the fluid within cavities near the leading edges of either stator blades in space or rotor blades in time to be driven radially inward relative to fluid near blade mid-pitch. This influence also produced large unsteady velocity fluctuations in the downstream cavity because of the passing of the downstream rotor blade.

Wellborn, Steven R.; Okiishi, Theodore H.

1996-01-01

81

Effect of endwall cooling on secondary flows in turbine stator vanes  

NASA Technical Reports Server (NTRS)

The effect of endwall cooling on the secondary flow behavior and the aerodynamic performance of a core turbine stator vane was determined. The investigation was conducted in a cold-air, full-annular cascade, where three-dimensional effects were obtained. Two endwall cooling configurations were tested. In the first configuration, the cooling holes were oriented so that the coolant was injected in line with the inviscid streamline direction. In the second configuration, the coolant was injected at an angle of 15 deg to the inviscid streamline direction and oriented towards the vane pressure stator. In both cases the stator vanes were solid and uncooled so that the effect of endwall cooling was obtained directly. Total-pressure surveys were taken downstream of the stator vanes over a range of cooling flows at the design, mean-radius, critical velocity ratio of 0.778. Changes in the total-pressure contours downstream of the vanes were used to obtain the effect of endwall cooling on the secondary flows in the stator.

Goldman, L. J.; Mclallin, K. L.

1977-01-01

82

Theoretical and experimental study of vibrational behaviour of laminated stators of electrical machines  

NASA Astrophysics Data System (ADS)

An accurate determination of the resonant frequencies and vibrational characteristics of a stator is essential in the design of quiet electrical machines. This paper presents both a fundamental theoretical and an experimental study of the vibrational behaviour of long and short laminated stators of electrical machines. The paper describes briefly the method of analysis, based on the three-dimensional theory of elasticity, for free vibrations of stators with encased construction. To prove the general validity of the analysis and to study the effect of windings, frame, and impregnation upon the resonant frequencies and vibrational behaviour of the stators of electrical machines, extensive experimental investigations were conducted on a number of stator models which include a solid model, long laminated, and short laminated models with and without windings, frame and impregnation. The paper compares the experimental and analytical results for some of these models which prove the general validity of the analysis. Finally, the paper also includes the important findings of these extensive investigations.

Singal, R. K.; Williams, K.; Verma, S. P.

1992-11-01

83

Extension of Useful Operating Range of Axial-Flow Compressors by Use of Adjustable Stator Blades  

NASA Technical Reports Server (NTRS)

A theory has been developed for resetting the blade angles of an axial-flow compressor in order to improve the performance at speeds and flows other than the design and thus extend the useful operating range of the compressor. The theory is readily applicable to the resetting of both rotor and stator blades or to the resetting of only the stator blades and is based on adjustment of the blade angles to obtain lift coefficients at which the blades will operate efficiently. Calculations were made for resetting the stator blades of the NACA eight-stage axial-flow compressor for 75 percent of design speed and a series of load coefficients ranging from 0.28 to 0.70 with rotor blades left at the design setting. The NACA compressor was investigated with three different blade settings: (1) the design blade setting, (2) the stator blades reset for 75 percent of design speed and a load coefficient of 0.48, and (3) the stator blades reset for 75 percent of design speed and a load coefficient of 0.65.

Sinnette, John T; Voss, William J

1948-01-01

84

Predicting broadband noise from a stator vane of a gas turbine engine  

NASA Technical Reports Server (NTRS)

A computer-implemented model of fan section of a gas turbine engine accounts for the turbulence in the gas flow emanating from the rotor assembly and impinging upon an inlet to the stator vane cascade. The model allows for user-input variations in the sweep and/or lean angles for the stator vanes. The model determines the resulting acoustic response of the fan section as a function of the turbulence and the lean and/or sweep angles of the vanes. The model may be embodied in software that is rapidly executed in a computer. This way, an optimum arrangement in terms of fan noise reduction is quickly determined for the stator vane lean and sweep physical positioning in the fan section of a gas turbine engine.

Hanson, Donald B. (Inventor)

2002-01-01

85

Strength design and reliability evaluation of a hybrid ceramic stator vane for industrial gas turbines  

NASA Astrophysics Data System (ADS)

Employing ceramic materials for the critical components of industrial gas turbines is anticipated to improve the thermal efficiency of power plants. We developed a first-stage stator vane for a 1300 C class, 20-MW industrial gas turbine. This stator vane has a hybrid ceramic/metal structure, to increase the strength reliability of brittle ceramic parts, and to reduce the amount of cooling air needed for metal parts as well. The strength design results of a ceramic main part are described. Strength reliability evaluation results are also provided based on a cascade test using combustion gas under actual gas turbine running conditions.

Nakakado, K.; Machida, T.; Miyata, H.; Hisamatsu, T.; Mori, N.; Yuri, I.

1995-04-01

86

The effect of teeth-on-stator labyrinth seals on rotor imbalance response  

E-print Network

THE EFFECT OF TEETH-ON-STATOR LABYRINTH SEALS ON ROTOR IMBALANCE RESPONSE A Thesis by EILEEN MARIE CONWAY Submitted to the Office of Graduate Studies of Texas ASM University in partial fulfillment of the requirements for the degree of MASTER... OF SCIENCE August 1991 Major Subject: Mechanical Engineering THE EFFECT OF TEETH-ON-STATOR LABYRINTH SEALS ON ROTOR IMBALANCE RESPONSE A Thesis by EILEEN MARIE CONWAY Approved as to style and content by: J1 I John M. Vance (Chair of Comminee...

Conway, Eileen Marie

2012-06-07

87

A comparison of experimental and theoretical results for labyrinth gas seals with honeycomb stators  

E-print Network

, and c) teeth on the sta- tor and steps or grooves on the rotor. Wright [4] hss published data on equivalent radial and tangential stiffnesses for single-cavity teeth-on-stator seals. Childs and Scharrer [5] have investigated teeth-on-rotor and teeth..., and c) teeth on the sta- tor and steps or grooves on the rotor. Wright [4] hss published data on equivalent radial and tangential stiffnesses for single-cavity teeth-on-stator seals. Childs and Scharrer [5] have investigated teeth-on-rotor and teeth...

Hawkins, Lawrence Allen

2012-06-07

88

Reduced Perceived Noise Low Tip Speed Fans as a Result of Abandoning Cutoff Stator Vane Numbers  

NASA Technical Reports Server (NTRS)

As fan tip speeds are reduced, broadband noise is becoming more important in the calculation of perceived noise. Past experience indicates that lower vane number stators with either constant chord or constant solidity may be a way to reduce broadband noise caused by the interaction of the rotor wake turbulence with the stators. A baseline fan and a low blade number fan were investigated to determine if a noise reduction was possible. The low vane number fan showed a 2 PndB and a 1.5 PNLT noise reduction. These reductions show that this is a viable technique for reducing the perceived noise of low tip speed fans.

Dittmar, James

1998-01-01

89

Scnarios d'interaction rotor/stator pour un compresseur haute pression d'un moteur d'hlicoptre  

E-print Network

Scénarios d'interaction rotor/stator pour un compresseur haute pression d'un moteur d'hélicoptère A plus de prévoir les zones d'interaction. Rotor-stator interaction scenarios for the centrifugal in the centrifugal com- pressor of helicopter engines when structural contacts occur between the blade

Boyer, Edmond

90

VOL. 6, NO. 5, SEPT.-OCT. 1990 J. PROPULSION 621 Stator/Rotor Interaction in a Transonic Turbine  

E-print Network

on the rotor blade, reflects upstream, and then reflects again off the stator blade Presented as Paper 88 and shows the large unsteadiness in the lift on the rotor blade. Basic NumericalMethod The flowfiVOL. 6, NO. 5, SEPT.-OCT. 1990 J. PROPULSION 621 Stator/Rotor Interaction in a Transonic Turbine

Giles, Mike

91

Ageing due to thermal cycling by start and stop cycles in lifetime estimation of hydroelectric generator stator windings  

Microsoft Academic Search

? Abstract -- The objective of this study is to present an approach to predict ageing due to thermal cycling by start and stop cycles in the lifetime estimation of hydroelectric generator stator windings. In this study a multi-stress electro-thermo- mechanical ageing model was applied for remaining lifetime calculations of stator windings. For various insulation systems the factors of the

Voitto I. J. Kokko

2011-01-01

92

Cause and analysis of stator and rotor failures in three-phase squirrel-cage induction motors  

Microsoft Academic Search

The squirrel cage induction motor has limitations, which, if exceeded, will result in premature failure of the stator or rotor. The authors identify the various causes of stator and rotor failures. A specific methodology is proposed to facilitate an accurate analysis of these failures. Failures of the bearings and lubrication systems are excluded

Austin H. Bonnett; George C. Soukup

1992-01-01

93

Pre-Design and Optimization of three phase homopolar SRM With double statoric winding and double massive rotor  

Microsoft Academic Search

This paper deals with the design of a three phase synchronous reluctant machine. This machine is constituted by two stators and two massive rotors. A homopolar exciting winding is jointly liable for stator. Due to three-dimensional geometry of the machine, the main object of this study is to develop very quick tools of design which allows defining motor performances. This

Christian BELALAHY; I. Radoanarivo; Tsarafidy RAMINOSOA; François-Michel SARGOS

2006-01-01

94

Digital signal processing control of induction machine`s torque and stator flux utilizing the direct stator flux field orientation method  

SciTech Connect

This paper presents a review of the Direct Stator Flux Field Orientation control method. This method can be used to control an induction motor`s torque and flux directly and is the application of interest for this thesis. This control method is implemented without the traditional feedback loops and associated hardware. Predictions are made, by mathematical calculations, of the stator voltage vector. The voltage vector is determined twice a switching period. The switching period is fixed throughout the analysis. The three phase inverter duty cycle necessary to control the torque and flux of the induction machine is determined by the voltage space vector Pulse Width Modulation (PWM) technique. Transient performance of either the flux or torque requires an alternate modulation scheme which is also addressed in this thesis. A block diagram of this closed loop system is provided. 22 figs., 7 tabs.

Seiz, J.B.

1997-04-01

95

Effects of blade-vane ratio and rotor-stator spacing of fan noise with forward velocity  

NASA Technical Reports Server (NTRS)

A research fan stage was acoustically tested in an anechoic wind tunnel with a 41 m/sec tunnel flow. Two stator vane numbers giving cut-on and cut-off conditions were tested at three rotor-stator spacings ranging from about 0.5 to 2.0 rotor chords. These two stators were designed for similar aerodynamic performance. Hot film anemometer turbulence measurements were made at the leading edge of the stator for each spacing. The cut-off criterion strongly controlled the fundamental tone level at all spacings. The trends with spacing of the wake defect upwash component at the stator tip showed good agreement with the corresponding cut-on acoustic tone levels.

Woodward, R. P.; Glaser, F. W.

1981-01-01

96

A new stator-flux orientation strategy for flux-switching permanent magnet motor based on current-hysteresis control  

NASA Astrophysics Data System (ADS)

A stator-flux orientation strategy based on current hysteresis for the flux-switching permanent magnet (FSPM) motor is proposed, in which the stator-PM FSPM motor is considered as a conventional rotor-PM surface-mounted motor and an equivalent rotor-orientated dq-axes synchronous reference frame is built although there are actually no rotary magnetic motive force produced by the stator magnets in the FSPM motor. Based on the proposed model, a vector-control strategy with current hysteresis for the FSPM motor drive is investigated and implemented on a dSPACE-based platform, and both the simulated and experimental results validate the effectiveness. It should be emphasized that the proposed stator-flux orientation strategy can be applied to other stator-PM machines (including doubly salient and flux-reversal PM machines) and other control methods (including space-vector pulsed-width-modification and direct torque control).

Hua, Wei; Cheng, Ming; Lu, Wei; Jia, Hongyun

2009-04-01

97

A finite volume method and experimental study of a stator of a piezoelectric traveling wave rotary ultrasonic motor.  

PubMed

Piezoelectric traveling wave rotary ultrasonic motors are motors that generate torque by using the friction force between a piezoelectric composite ring (or disk-shaped stator) and a metallic ring (or disk-shaped rotor) when a traveling wave is excited in the stator. The motor speed is proportional to the amplitude of the traveling wave and, in order to obtain large amplitudes, the stator is excited at frequencies close to its resonance frequency. This paper presents a non-empirical partial differential equations model for the stator, which is discretized using the finite volume method. The fundamental frequency of the discretized model is computed and compared to the experimentally-measured operating frequency of the stator of Shinsei USR60 piezoelectric motor. PMID:24210273

Bolborici, V; Dawson, F P; Pugh, M C

2014-03-01

98

Effects of long-chord acoustically treated stator vanes on fan noise. 2: Effect of acoustical treatment  

NASA Technical Reports Server (NTRS)

A set of long chord stator vanes was designed to replace the vanes in an existing fan stage. The long chord stator vanes consisted of a turning section and axial extension pieces, all of which incorporated acoustic damping material. The long chord stator vanes were tested in two lengths, with the long version giving more noise reduction than the short, primarily because of the additional lining material. The noise reduction achieved with the acoustically treated long chord stator vanes was compared with the reduction achieved by an acoustically treated exhaust splitter. The long chord stator was at least as good as the splitter as a method for incorporating acoustic lining material. In addition, comparing an acoustic three ring inlet and an acoustic wall-only inlet discloses that the wall-only inlet could be used in an engine where the noise reduction requirements are not too stringent.

Dittmar, J. H.; Scott, J. N.; Leonard, B. R.; Stakolich, E. G.

1976-01-01

99

Nonlinear torque and stator flux controller for induction motor drive based on adaptive input–output feedback linearization and sliding mode control  

Microsoft Academic Search

This paper describes a nonlinear torque and stator flux controller for three phase induction motor (IM) drives on the basis of a space vector modulation (SVM) scheme. Using the IM fifth order model in a fixed “ab” axis reference frame with stator currents (isa ,isb) and stator fluxes (?sa,?sb) as state variables, a sliding mode (SM) torque and flux controller

R. Yazdanpanah; J. Soltani; G. R. Arab Markadeh

2008-01-01

100

Comparison of Computational Aeroacoustics Prediction of Acoustic Transmission Through a 3D Stator With Experiment  

NASA Technical Reports Server (NTRS)

In this paper, numerical predictions of acoustic transmission through a 3D stator obtained using the NASA BASS code are compared with experimentally measured data. The influence of vane count and stagger as well as frequency and mode order on the transmission loss is investigated. The data-theory comparisons indicate that BASS can predict all the important trends observed in the experimental data.

Hixon, Ray; Envia, Edmane; Dahl, Milo; Sutliff, Daniel L.

2014-01-01

101

Modelling of the travelling wave piezoelectric motor stator: an integrated review and new perspective  

Microsoft Academic Search

Articles from different areas which are closely related to the modelling of the stator of travelling wave ultrasonic motors (TWUMs) are reviewed in this work. Thus, important issues relevant to this problem are identified from the areas of vibration of annular plates, laminated plate theories, and modelling of piezoelectric transducers. From this integrated point of view, it becomes clear that

H. RodRiguez; R. CeRes; J. L. Pons

102

Research on location and speed detection for high speed maglev train based on long stator  

Microsoft Academic Search

Location and speed detection (LSD) is one of the key technologies of high speed maglev train. The traction system needs precise location and speed information to carry out the traction task of the train normally and reliably. Firstly, several conventional location and speed detection methods are introduced. And then, the method based on the tooth and slots of long stator

Xue Song; Dai Chunhui; Long Zhiqiang

2010-01-01

103

Hydroacoustic simulation of rotor-stator interaction in resonance conditions in Francis pump-turbine  

Microsoft Academic Search

Combined effect of rotating pressure field related to runner blade and wakes of wicket gates leads to rotor stator interactions, RSI, in Francis pump-turbines. These interactions induce pressures waves propagating in the entire hydraulic machine. Superposition of those pressure waves may result in standing wave in the spiral casing and rotating diametrical mode in the guide vanes and can cause

C. Nicolet; N. Ruchonnet; S. Alligné; J. Koutnik; F. Avellan

2010-01-01

104

Numerical study of a rotor/stator interaction case experimentally simulated with an industrial compressor  

E-print Network

Numerical study of a rotor/stator interaction case experimentally simulated with an industrial energy efficiency may be achieved by minimizing the clearance between the rotating blade tips, unexpected abradable wear removal mechanisms were observed in experi- mental set-ups and during maintenance

Paris-Sud XI, Université de

105

STUDY OF COMPONENT MODE SYNTHESIS METHODS IN A ROTOR-STATOR  

E-print Network

to the one used by Legrand [1]. The main difference is the coupling of the 22 blades which is performedSTUDY OF COMPONENT MODE SYNTHESIS METHODS IN A ROTOR-STATOR INTERACTION CASE A. Batailly, Ge, France Cet article fait partie des actes de la conférence ASME DETC 2007 Abstract The study of rotor

Paris-Sud XI, Université de

106

A Parametric Study of Unsteady Rotor-Stator Interaction in a Simplified Francis Turbine  

NASA Astrophysics Data System (ADS)

CFD analysis is becoming a critical stage in the design of hydroturbines. However, its capability to represent unsteady flow interactions between the rotor and stator (which requires a 360-degree, mesh-refined model of the turbine passage) is hindered. For CFD to become a more effective tool in predicting the performance of a hydroturbine, the key interactions between the rotor and stator need to be understood using current numerical methods. As a first step towards evaluating this unsteady behavior without the burden of a computationally expensive domain, the stator and Francis-type rotor blades are reduced to flat plates. Local and global variables are compared using periodic, semi-periodic, and 360-degree geometric models and various turbulence models (k-omega, k-epsilon, and Spalart-Allmaras). The computations take place within the OpenFOAM^ environment and utilize a general grid interface (GGI) between the rotor and stator computational domains. The rotor computational domain is capable of dynamic rotation. The results demonstrate some of the strengths and limitations of utilizing CFD for hydroturbine analysis. These case studies will also serve as tutorials to help others learn how to use CFD for turbomachinery.

Wouden, Alex; Cimbala, John; Lewis, Bryan

2011-11-01

107

Implications for the application of adjustable speed drive electronics to motor stator winding insulation  

Microsoft Academic Search

Medium voltage (2300V to 4160V) motor stator insulation has been designed to withstand voltage surges from circuit breaker operation for many decades. It is probable that the surges created by ASDs will not pose a threat to properly designed and manufactured insulation. However, as ASDs become more popular in the higher voltage ranges, we will have to watch carefully to

J. A. Oliver; G. C. Stone

1995-01-01

108

Dynamic pressure and shear stress measurements on the stator wall of whirling annular seals  

E-print Network

Dynamic pressure and shear stress measurements on the stator wall of whirling annular seals are presented. Two flow conditions (Re=12,000 & 24,000), two seal speeds (Ta=3,300 & 6,600) and three eccentricity ratios (0, 10, & 50% of the clearance...

Winslow, Robert Bradley

2012-06-07

109

Transient technique for measuring heat transfer coefficients on stator airfoils in a jet engine environment  

Microsoft Academic Search

A transient technique was used to measure heat transfer coefficients on stator airfoils in a high-temperature annular cascade at real engine conditions. The transient response of thin film thermocouples on the airfoil surface to step changes in the gas stream temperature was used to determine these coefficients. In addition, gardon gages and paired thermocouples were also utilized to measure heat

H. J. Gladden; M. P. Proctor

1985-01-01

110

EXPERIMENTALAND NUMERICAL INVESTIGATION OF TURBULENT AIR FLOW BEHAVIOUR IN A ROTOR-STATOR  

E-print Network

1 EXPERIMENTALAND NUMERICAL INVESTIGATION OF TURBULENT AIR FLOW BEHAVIOUR IN A ROTOR-STATOR CAVITY Marseille cédex 20, France poncet@l3m.univ-mrs.fr ABSTRACT The present work considers the turbulent air flow agreement for this set of flow control parameters. NOMENCLATURE radius of the rotating hub outer radius

Paris-Sud XI, Université de

111

Traveling-wave piezoelectric linear motor Part I: the stator design.  

PubMed

A new type of piezoelectric linear motor incorporating a traveling wave has been developed. The linear motor is comprised of a stator and a carriage. The stator design, which consists of a meander-line structure and gear teeth mounted on the meander-line structure, is the focus of this article. The meander-line structure is constructed with bimorph actuators arranged in a line. These actuators are driven by two phased sets of alternating current (ac) in order to generate a traveling wave. The traveling wave is transferred to the gear teeth, by which the carriage is driven. Modeling of the stator is derived by use of a strain energy method. The performance of various materials is evaluated by analytical and experimental methods. The analytical and the experimental results are quite approximate. Modal analysis is investigated using ANSYS. Appropriate modes associated with ultrasonic levels of resonant frequency are selected to obtain desired motion and to enhance the output performance. Surface speed for various applied input voltage are studied and indicate a nearly linear relationship. The stator in combination with the carriage makes up the linear motor. PMID:17441594

Ting, Yung; Chen, Liang-Chiang; Li, Chun-Chung; Huang, Jeng-Lin

2007-04-01

112

Stator and rotor resistance observers for induction motor drive using fuzzy logic and artificial neural networks  

Microsoft Academic Search

This paper presents a new observer for the rotor resistance of an indirect vector controlled induction motor drive using artificial neural networks supplemented by a fuzzy logic based stator resistance observer. The error between the rotor flux linkages based on a neural network model and a voltage model is back propagated to adjust the weights of the neural network model

Baburaj Karanayil; Muhammed Fazlur Rahman; Colin Grantham

2005-01-01

113

Stator and rotor resistance observers for induction motor drive using fuzzy logic and artificial neural networks  

Microsoft Academic Search

This paper presents a new method of on-line estimation for the stator and rotor resistances of the induction motor in the indirect vector controlled drive, using fuzzy logic and artificial neural networks. The back propagation algorithm is used for the training of the neural networks for rotor resistance identification. The error between the desired state variable of an induction motor

Baburaj Karanayil; Muhammed Fazlur Rahman; Colin Grantham

2003-01-01

114

Rotor speed estimation for indirect stator flux oriented induction motor drive based on MRAS scheme JES  

Microsoft Academic Search

In this paper, a conventional indirect stator flux oriented controlled (ISFOC) induction motor drive is presented. In order to eliminate the speed sensor, an adaptation algorithm for tuning the rotor speed is proposed. Based on the model reference adaptive system (MRAS) scheme, the rotor speed is tuned to obtain an exact ISFOC induction motor drive. The reference and adjustable models,

Youssef Agrebi; Moncef Triki; Yassine Koubaa; Mohamed Boussak

115

EEMD-based wind turbine bearing failure detection using the generator stator current homopolar component  

E-print Network

EEMD-based wind turbine bearing failure detection using the generator stator current homopolar in wind turbine generators for stationary and non stationary cases. Keyword: Wind turbine, induction on the installed equipment because they are hardly accessible or even inaccessible [1]. 1.1. Wind turbine failure

Boyer, Edmond

116

Wind Turbine Bearing Failure Detection Using Generator Stator Current Homopolar Component  

E-print Network

Wind Turbine Bearing Failure Detection Using Generator Stator Current Homopolar Component Ensemble Empirical Mode Decomposition (EEMD) as a tool for failure detection in wind turbine generators for stationary and non stationary cases. Index Terms-Wind turbine, induction generator, bearing failure, ensemble

Paris-Sud XI, Université de

117

Epoxy Adhesives for Stator Magnet Assembly in Stirling Radioisotope Generators (SRG)  

NASA Technical Reports Server (NTRS)

As NASA seeks to fulfill its goals of exploration and understanding through missions planned to visit the moons of Saturn and beyond, a number of challenges arise from the idea of deep space flight. One of the first problems associated with deep space travel is electrical power production for systems on the spacecraft. Conventional methods such as solar power are not practical because efficiency decreases substantially as the craft moves away from the Sun. The criterion for power generation during deep space missions are very specific, the main points requiring high reliability, low mass, minimal vibration and a long lifespan. A Stirling generator, although fairly old in concept, is considered to be a potential solution for electrical power generation for deep space flight. A Stirling generator works on the same electromagnetic principles of a standard generator, using the linear motion of the alternator through the stationary stator which produces electric induction. The motion of the alternator, however, is produced by the heating and cooling dynamics of pressurized gases. Essentially heating one end and cooling another of a contained gas will cause a periodic expansion and compression of the gas from one side to the other, which a displacer translates into linear mechanical motion. NASA needs to confirm that the materials used in the generator will be able to withstand the rigors of space and the life expectancy of the mission. I am working on the verification of the epoxy adhesives used to bond magnets to the steel lamination stack to complete the stator; in terms of in-service performance and durability under various space environments. Understanding the proper curing conditions, high temperature properties, and degassing problems as well as production difficulties are crucial to the long term success of the generator. system and steel substrate used in the stator. To optimize the curing conditions of the epoxies, modulated differential scanning calorimetry analysis was done as a function of cure time and temperatures. Adhesion bond strength was tested at various temperatures with lap shear samples using Hiperco 50 substrate to ensure that the proper adhesive is being used. To try and solve the problem of bondline thickness, micro glass beads of 0.0017" in diameter were investigated to see if any other physical properties of the epoxy were affected. Efforts will be made to develop a standard, optimized, fabrication process/procedure of sub-scale magnet-stator assemblies for various adhesive performance evaluation studies under simulated generator conditions. Also, accelerated aging testing will be done in a pressurized canister with stator assembly samples for three years to verify if any degassing or thermal degradation of the epoxy occurs. The necessity of verifying the correct epoxy adhesive system for the stator magnet in the SRG is crucial because failure of the stator assembly would jeopardize the electrical system, and thereby the entire mission itself. My work involves specimen fabrications, testing, and data analyses of the epoxy adhesive system for the stator magnet in the SRG is crucial because failure of the stator assembly would jeopardize the electrical system, and thereby the entire mission itself.

Cater, George M.

2004-01-01

118

System and method for determining stator winding resistance in an AC motor using motor drives  

DOEpatents

A system and method for determining the stator winding resistance of AC motors is provided. The system includes an AC motor drive having an input connectable to an AC source and an output connectable to an input terminal of an AC motor, a pulse width modulation (PWM) converter having switches therein to control current flow and terminal voltages in the AC motor, and a control system connected to the PWM converter. The control system generates a command signal to cause the PWM converter to control an output of the AC motor drive corresponding to an input to the AC motor, selectively generates a modified command signal to cause the PWM converter to inject a DC signal into the output of the AC motor drive, and determines a stator winding resistance of the AC motor based on the DC signal of at least one of the voltage and current.

Lu, Bin; Habetler, Thomas G; Zhang, Pinjia

2013-02-26

119

A low-temperature high-sensitivity torsion balance magnetometer with in situ stator adjustment  

NASA Astrophysics Data System (ADS)

Torsion balance magnetometry can be used as a versatile probe of two-dimensional electron systems. We have developed a highly sensitive magnetometer, utilizing capacitive proximity detection of the rotor position, for use at temperatures below 10 mK. The instrument incorporates two piezo-electric linear motors to enable the stator positions to be adjusted in situ at base temperature. The magnetometer responsivity is inversely proportional to the square of the rotor-stator separation and the novel linear motor technique, accompanied by effective vibration isolation and optimized capacitance bridge electronics, achieves a resolution 6.5×10-12 N m Hz-1/2. This resolution, together with the low temperatures attainable, allows for experiments that probe the family of quantum fluid states responsible for the fractional quantum Hall effect, even at filling factors greater than one.

Matthews, A. J.; Usher, A.; Williams, C. D. H.

2004-08-01

120

Analytical study of nonlinear synchronous full annular rub motion of flexible rotor–stator system and its dynamic stability  

Microsoft Academic Search

The nonlinear synchronous full annular rub motion of a flexible rotor induced by the mass unbalance and the contact-rub force\\u000a with rigid and flexible stator is studied analytically. The nonlinear property is due to the dry friction force between stator\\u000a and rotor. The exact solutions of the synchronous full annular rub motion and its run speed regions are obtained. The

Guo Fa Zhang; Wei Nan Xu; Bin Xu; Wen Zhang

2009-01-01

121

Study of stator-vane fluctuating pressures in a turbofan engine for static and flight tests  

Microsoft Academic Search

As part of a program to study the fan noise generated from turbofan engines, fluctuating surface pressures induced by fan-rotor wakes were measured on core- and bypass-stator outlet guide vanes of a modified JT15D-1 engine. Tests were conducted with the engine operating on an outdoor test stand and in flight. The amplitudes of pressures measured at fan-rotor blade-passage fundamental frequencies

A. W. Mueller

1984-01-01

122

A nickel base alloy, NASA WAZ-16, with potential for gas turbine stator vane application  

NASA Technical Reports Server (NTRS)

A nickel-base superalloy based on the nickel-aluminum-tungsten system designated WAZ-16 was developed for high strength in the 1095 C (2000 F) to 1205 C (2200 F) range. Its tensile strength at the latter temperature is approximately 186 MN/m2 (27,000 psi). The combination of properties of the alloy suggest that it has potential as a stator vane material in advanced gas turbine engines.

Waters, W. J.; Freche, J. C.

1974-01-01

123

What stator current processing-based technique to use for induction motor rotor faults diagnosis?  

Microsoft Academic Search

In recent years, marked improvement has been achieved in the design and manufacture of stator winding. However, motors driven by solid-state inverters undergo severe voltage stresses due to rapid switch-on and switch-off of semiconductor switches. Also, induction motors are required to operate in highly corrosive and dusty environments. Requirements such as these have spurred the development of vastly improved insulation

Mohamed El Hachemi Benbouzid; Gerald B. Kliman

2003-01-01

124

Incipient bearing fault detection via wind generator stator current and wavelet filter  

Microsoft Academic Search

Bearing faults constitute a significant portion of all faults in rotating machines, including wind turbine generators (WTGs). Current-based bearing fault detection has significant advantages over traditional vibration-based methods in terms of cost, implementation, and system reliability. This paper proposes a new wavelet filter-based method for incipient bearing fault detection using electric machine stator currents. The proposed method can dramatically increase

Xiang Gong; Wei Qiao; Wei Zhou

2010-01-01

125

Vibration response of a cracked rotor in presence of rotor stator rub  

NASA Astrophysics Data System (ADS)

Fatigue crack and rotor-stator rub are two important faults in rotating machinery. Researchers have mostly studied the vibration behavior of a rotor with crack and rotor-stator rub separately. However, once the crack is developed in a rotor, the rotor is more likely to make contact with stator under tight clearance conditions, due to increased vibration level. The present study is aimed to examine vibration response of the cracked rotor in presence of common rotor faults such as unbalance and rotor stator rub. Numerical and experimental investigations are carried out and steady-state vibration analysis is presented. Experimental investigation for a multifault rotor system is attempted for the first time. The full spectrum analysis has been used effectively to extract the distinctive directional features of these rotor faults. The investigation focuses on directional nature of the higher harmonics for identification of rub in the cracked rotor. The study reveals that spectrum rich in spectral lines is a rub symptom. However, these higher harmonics are weaker than the 1X response. Rub in uncracked rotor excites forward and backward whirling frequency components almost equally. Cracked rotor without rub exhibits strongly forward whirling vibrations. Rotor rub in the cracked rotor reveals different response compared with the uncracked rotor, particularly the nature of 2X and higher harmonics at corresponding subharmonic resonances. Backward whirling nature of 2X frequency component as well as that of higher harmonic (that matches with the bending natural frequency) at corresponding subharmonic resonances, has been proposed for diagnosis of rotor rub in cracked rotor.

Patel, Tejas H.; Darpe, Ashish K.

2008-11-01

126

Experimental study on flow and mass transfer in rotor-stator disk cavities  

Microsoft Academic Search

An experimental study has been performed in an attempt to seek some possibilities of obtaining the solutions of heat transfer\\u000a problems related to rotor-stator disk cavity systems of gas turbine engines by analogy with corresponding problems in mass\\u000a transfer which arises from using naphthalene sublimation technique. Measurements are made to examine the effects of rotational\\u000a Reynolds number, the flow rate

H. C. Kim; J. Y. Yoo; H. S. Kang; S. W. Kim

1995-01-01

127

Novel Identification Method of Stator Single Phase-to-Ground Fault for Cable-Wound Generators  

Microsoft Academic Search

A new criterion to detect the stator single phase-to-ground fault for Powerformer is proposed in this paper, which is based on the direction of zero-sequence compositive power flow. By virtue of the analysis of new fault characteristics of Powerformer and the comparison with conventional methods, a novel identification scheme is put forward. The proposed approach detects the ground fault by

Yan Gao; Xiangning Lin; Qing Tian; Pei Liu

2008-01-01

128

Two flagellar stators and their roles in motility and virulence in Pseudomonas syringae pv. tabaci 6605  

Microsoft Academic Search

The motor proteins around the flagellar basal body consist of two cytoplasmic membrane proteins, MotA and MotB, and function\\u000a as a complex that acts as the stator to generate the torque that drives rotation. Genome analysis of several Pseudomonas syringae pathovars revealed that there are two sets of genes encoding motor proteins: motAB and motCD. Deduced amino acid sequences for

Eiko Kanda; Takafumi Tatsuta; Tomoko Suzuki; Fumiko Taguchi; Kana Naito; Yoshishige Inagaki; Kazuhiro Toyoda; Tomonori Shiraishi; Yuki Ichinose

2011-01-01

129

Diagnostics of an induction-motor rotor by the spectral analysis of stator currents  

NASA Astrophysics Data System (ADS)

A method for achieving more efficient revealing and more unambiguous evaluation of various kinds of defects in the induction-motor (IM) rotor, which is based on changes occurring in the characteristic signs of the spectrum of the stator current, is presented. The results and analysis of measurements performed for artificially specified cases of faults in the rotor of a small-capacity IM are presented.

Weinreb, K.

2013-12-01

130

Two-stage fan. 4: Performance data for stator setting angle optimization  

NASA Technical Reports Server (NTRS)

Stator setting angle optimization tests were conducted on a two-stage fan to improve efficiency at overspeed, stall margin at design speed, and both efficiency and stall margin at partspeed. The fan has a design pressure ratio of 2.8, a flow rate of 184.2 lb/sec (83.55 kg/sec) and a 1st-stage rotor tip speed of 1450 ft/sec (441.96 in/sec). Performance was obtained at 70,100, and 105 percent of design speed with different combinations of 1st-stage and 2nd-stage stator settings. One combination of settings, other than design, was common to all three speeds. At design speed, a 2.0 percentage point increase in stall margin was obtained at the expense of a 1.3 percentage point efficiency decrease. At 105 percent speed, efficiency was improved by 1.8 percentage points but stall margin decreased 4.7 percentage points. At 70 percent speed, no change in stall margin or operating line efficiency was obtained with stator resets although considerable speed-flow requlation occurred.

Burger, G. D.; Keenan, M. J.

1975-01-01

131

Periodic transition on an axial compressor stator: Incidence and clocking effects. Part 1: Experimental data  

SciTech Connect

Periodic wake-induced transition on the outlet stator of a 1.5-stage axial compressor is examined using hot-film arrays on both the suction and pressure surfaces. The time-mean surface pressure distribution is varied by changing the blade incidence, while the free-stream disturbance field is altered by clocking of the stator relative to an inlet guide vane row. Ensemble-averaged plots of turbulent intermittency and relaxation factor (extent of calmed flow following the passage of a turbulent spot) are presented. These show the strength of periodic wake-induced transition phenomena to be significantly influenced by both incidence and clocking effects. The nature and extent of transition by other modes (natural, bypass, and separated flow transition) are altered accordingly. Leading edge and midchord separation bubbles are affected in a characteristically different manner by changing free-stream periodicity. There are noticeable differences between suction and pressure surface transition behavior, particularly as regards the strength and extent of calming. In Part 2 of this paper, the transition onset observations from the compressor stator are used to evaluate the quasi-steady application of conventional transition correlations to predict unsteady transition onset on the blading of an embedded axial compressor stage.

Walker, G.J.; Hughes, J.D. [Univ. of Tasmania, Hobart (Australia). School of Engineering; Solomon, W.J. [Ohio Aerospace Institute/General Electric Aircraft Engines, Cincinnati, OH (United States)

1999-07-01

132

Active Flow Separation Control of a Stator Vane Using Surface Injection in a Multistage Compressor Experiment  

NASA Technical Reports Server (NTRS)

Micro-flow control actuation embedded in a stator vane was used to successfully control separation and improve near stall performance in a multistage compressor rig at NASA Glenn. Using specially designed stator vanes configured with internal actuation to deliver pulsating air through slots along the suction surface, a research study was performed to identify performance benefits using this microflow control approach. Pressure profiles and unsteady pressure measurements along the blade surface and at the shroud provided a dynamic look at the compressor during microflow air injection. These pressure measurements lead to a tracking algorithm to identify the onset of separation. The testing included steady air injection at various slot locations along the vane. The research also examined the benefit of pulsed injection and actively controlled air injection along the stator vane. Two types of actuation schemes were studied, including an embedded actuator for on-blade control. Successful application of an online detection and flow control scheme will be discussed. Testing showed dramatic performance benefit for flow reattachment and subsequent improvement in diffusion through the use of pulsed controlled injection. The paper will discuss the experimental setup, the blade configurations, and preliminary CFD results which guided the slot location along the blade. The paper will also show the pressure profiles and unsteady pressure measurements used to track flow control enhancement, and will conclude with the tracking algorithm for adjusting the control.

Culley, Dennis E.; Bright, Michelle M.; Prahst, Patricia S.; Strazisar, Anthony J.

2003-01-01

133

Aerodynamic performances of three fan stator designs operating with rotor having tip speed of 337 meters per second and pressure ratio of 1.54. 1: Experimental performance  

NASA Technical Reports Server (NTRS)

The aerodynamic performances of four stator-blade rows are presented and evaluated. The aerodynamic designs of two of these stators were compromised to reduce noise, a third design was not. On a calculated operating line passing through the design point pressure ratio, the best stator had overall pressure-ratio and efficiency decrements of 0.031 and 0.044, respectively, providing a stage pressure ratio of 1.483 and efficiency of 0.865. The other stators showed some correctable deficiencies due partly to the design compromises for noise. In the end-wall regions blade-element losses were significantly less for the shortest chord studied.

Gelder, T. F.

1980-01-01

134

Influence of inlet nozzle on secondary flow in axial stator blade cascade  

NASA Astrophysics Data System (ADS)

This paper deals with numerical modelling of a turbulent compressible flow through an axial stator blade cascade. An attention is paid to the influence of the geometry of the inlet nozzle on the secondary flows in the blade cascade. The flow-field is divided on two parts: inlet nozzle, where a model of a 2D axisymmetric flow is used and the blade cascade, which is solved by a model of a fully 3D flow. The connection of the 2D axisymmetric model and the fully 3D model is proposed in this work.

Straka, Petr; Šimák, Jan; Pelant, Jaroslav

2014-08-01

135

Low Speed, 2-D Rotor/Stator Active Noise Control at the Source Demonstration  

NASA Technical Reports Server (NTRS)

Wake/blade-row interaction noise produced by the Annular Cascade Facility at Purdue University has been modeled using the LINFLO analysis. Actuator displacements needed for complete cancellation of the propagating acoustic response modes have been determined, along with the associated actuator power requirements. As an alternative, weighted least squares minimization of the total far-field sound power using individual actuators has also been examined. Attempts were made to translate the two-dimensional aerodynamic results into three-dimensional actuator requirements. The results lie near the limit of present actuator technology. In order to investigate the concept of noise control at the source for active rotor/stator noise control at the source, various techniques for embedding miniature actuators into vanes were examined. Numerous miniature speaker arrangements were tested and analyzed to determine their suitability as actuators for a demonstration test in the Annular Cascade Facility at Purdue. The best candidates demonstrated marginal performance. An alternative concept to using vane mounted speakers as control actuators was developed and tested. The concept uses compression drivers which are mounted externally to the stator vanes. Each compression driver is connected via a tube to an air cavity in the stator vane, from which the driver signal radiates into the working section of the experimental rig. The actual locations and dimensions of the actuators were used as input parameters for a LINFLO computational analysis of the actuator displacements required for complete cancellation of tones in the Purdue experimental rig. The actuators were designed and an arrangement determined which is compatible with the Purdue experimental rig and instrumentation. Experimental tests indicate that the actuators are capable of producing equivalent displacements greater than the requirements predicted by the LINFLO analysis. The acoustic output of the actuators was also found to be unaffected by the presence of air flow representative of the Purdue experimental rig. A test of the active noise control at the source concept for rotor/stator active noise control was demonstrated. This 2-D test demonstrated conclusively the simultaneous reduction of two acoustic modes. Reductions of over 10 dB were obtained over a wide operating range.

Simonich, John C.; Kousen, Ken A.; Zander, Anthony C.; Bak, Michael; Topol, David A.

1997-01-01

136

Detent torque from the soft magnetic stator stack of a hybrid stepper motor  

NASA Astrophysics Data System (ADS)

The residual magnetism present in the stator stack of a hybrid stepper motor, which will be of the last excited polarity, will develop a detent torque, similar to the static torque of the last excited phase, but with reduced excitation. The predominant component is fundamental. Even though this torque is the result of the stator excitation, it can be considered as a detent torque as it is available when the stator excitation is withdrawn. This detent torque is in addition to the inherent one due to the rotor permanent magnet, and it will be present until the next phase is switched ON. Once the excitation is removed from the second phase, because of the hysteresis the detent torque will be available, similar to the static torque profile for phase 2, but with less excitation. This means because of the hysteresis the detent torque follows the static torque of the phases. The magnitude of this detent torque will depend upon the level to which the phase was excited. Experiments have been carried out on a 0.5° hybrid stepper motor to study the effects of the excitation on the detent torque profiles. Harmonic analyses of the measured detent torque curves had been carried out and it is seen that the fundamental detent torque increases with the excitation and also follows the respective phases. Therefore, the residual flux density and the coercive force of the soft magnetic material used for the stator stack have to be as small as possible to get rid of this effect. Controlling a hybrid stepper motor by a suitable switching scheme for a given application requires the measured static torque profiles of the motor for all the phases at the exact working voltage (or voltages in case of a variable voltage supply) and detent torque profiles both before and after excitation. Harmonic spectrum of the measured static and detent torque profiles have to be accounted for while simulating stepping behavior of the motor, from which an appropriate switching scheme can be arrived at.

Rajagopal, K. R.; Singh, Bhim; Singh, B. P.

2003-05-01

137

Detection of stator winding faults in induction machines using flux and vibration analysis  

NASA Astrophysics Data System (ADS)

This work aims at presenting the detection and diagnosis of electrical faults in the stator winding of three-phase induction motors using magnetic flux and vibration analysis techniques. A relationship was established between the main electrical faults (inter-turn short circuits and unbalanced voltage supplies) and the signals of magnetic flux and vibration, in order to identify the characteristic frequencies of those faults. The experimental results showed the efficiency of the conjugation of these techniques for detection, diagnosis and monitoring tasks. The results were undoubtedly impressive and can be adapted and used in real predictive maintenance programs in industries.

Lamim Filho, P. C. M.; Pederiva, R.; Brito, J. N.

2014-01-01

138

Performance evaluation of traveling wave ultrasonic motor based on a model with visco-elastic friction layer on stator.  

PubMed

A new visco-elastic contact model of traveling wave ultrasonic motor (TWUSM) is proposed. In this model, the rotor is assumed to be rigid body and the friction material on stator teeth surface to be visco-elastic body. Both load characteristics of TWUSM, such as rotation speed, torque and efficiency, and effects of interface parameters between stator and rotor on output characteristic of TWUSM can be calculated and simulated numerically by using MATLAB method based on this model. This model is compared with that one of compliant slider and rigid stator. The results show that this model can obtain bigger stall torque. The simulated results are compared with test results, and found that their load characteristics have good agreement. PMID:16844172

Qu, Jianjun; Sun, Fengyan; Zhao, Chunsheng

2006-12-01

139

Combined fringe and Fabry-Perot laser anemometer for three component velocity measurements in turbine stator cascade facility  

NASA Technical Reports Server (NTRS)

A laser anemometer is described that was developed for use in a 508 mm diameter annular turbine stator cascade facility. All three velocity components are measured through a single restricted optical port, both within the stator vane row and downstream of the vanes. The measurements are made through a cylindrical window in the casing that matches the tip radius of the cascade. The stator tested has a contoured hub endwall that results in a large radial flow near the hub. The anemometer uses a standard fringe configuration (LFA) with a fluorescent aerosol seed to measure the axial and circumferential velocity components. The radial component is measured with a confocal Fabry-Perot interferometer. The two configurations are combined in a single optical system and can operate simultaneously. Data are presented to illustrate the capabilities of the system.

Seasholtz, R. G.; Goldman, L. J.

1986-01-01

140

Combined fringe and Fabry-Perot laser anemometer for 3 component velocity measurements in turbine stator cascade facility  

NASA Technical Reports Server (NTRS)

A laser anemometer is described that was developed for use in a 508 mm diameter annular turbine stator cascade facility. All three velocity components are measured through a single restricted optical port, both within the stator vane row and downstream of the vanes. The measurements are made through a cylindrical window in the casing that matches the tip radius of the cascade. The stator tested has a contoured hub endwall that results in a large radial flow near the hub. The anemometer uses a standard fringe configuration (LFA) with a fluorescent aerosol seed to measure the axial and circumferential velocity components. The radial component is measured with a confocal Fabry-Perot interferometer. The two configurations are combined in a single optical system and can operate simultaneously. Data are presented to illustrate the capabilities of the system.

Seasholtz, Richard G.; Goldman, Louis J.

1986-01-01

141

Application of the largest Lyapunov exponent for the diagnosis of rotor-to-stator rub in rotating machinery  

NASA Astrophysics Data System (ADS)

Vibration based diagnosis has played a vital role in the crucial analysis of faults in rotating machinery. The conventional vibration techniques currently being used in the industry are however not able to effectively identify nonlinear or complex signals due to, for example, rotor-to-stator rub. This paper reports on the application of the largest Lyapunov Exponent ?1 to diagnose the severity of rotor-to-stator rub in rotating machinery. The method of time delay was employed to reconstruct the vibration signal obtained from numerical simulation of a Jeffcott rotor subjected to rotor-to-stator rub. Numerical results show clear correlation between the increase of rub severity with the invariant quantity ?1 investigated in this work. Two different algorithms for the computation of ?1 were employed in this research, namely the Wolf algorithm and the Rosenstein algorithm.

ChangJie, Colin Heng; Inayat-Hussain, Jawaid I.

2014-10-01

142

Preparation of emulsions by rotor-stator homogenizer and ultrasonic cavitation for the cosmeceutical industry.  

PubMed

Oil-in-water (O/W) nanoemulsions play an important key role in transporting bioactive compounds into a range of cosmeceutical products to the skin. Small droplet sizes have an inherent stability against creaming, sedimentation, flocculation, and coalescence. O/W emulsions varying in manufacturing process were prepared. The preparation and characterization of O/W nanoemulsions with average diameters of as low as 62.99 nm from palm oil esters were carried out. This was achieved using rotor-stator homogenizer and ultrasonic cavitation. Ultrasonic cell was utilized for the emulsification of palm oil esters and water in the presence of mixed surfactants, Tween 80 and Span 80 emulsions with a mean droplet size of 62.99 nm and zeta potential value at -37.8 mV. Results were comparable with emulsions prepared with rotor-stator homogenizer operated at 6000 rpm for 5 min. The stability of the emulsions was evaluated through rheology measurement properties. This included non-Newtonian viscosity, elastic modulus G', and loss modulus G?. A highly stable emulsion was prepared using ultrasonic cavitation comprising a very small particle size with higher zeta potential value and G' > G? demonstrating gel-like behavior. PMID:23089355

Han, Ng Sook; Basri, Mahiran; Abd Rahman, Mohd Basyaruddin; Abd Rahman, Raja Noor Zaliha Raja; Salleh, Abu Bakar; Ismail, Zahariah

2012-01-01

143

ADAPTIVE FUZZY SLIDING-MODE CONTROL OF SPEED SENSORLESS UNIVERSAL FIELD ORIENTED INDUCTION MOTOR DRIVE WITH ON-LINE STATOR RESISTANCE TUNING  

Microsoft Academic Search

In this paper, a speed sensorless induction motor drive is introduced which is direct vector controlled in a universal field-oriented (UFO) reference frame. This chosen reference frame is easily linked with direct and indirect rotor, stator and air gap field orientation control schemes of the induction machine (IM) drives using a stator to rotor virtual turn ratio. Based on partial

J. SOLTANI; Y. ABDOLMALEKI; M. HAJIAN

144

Design and testing of swept and leaned outlet guide vanes to reduce stator-strut-splitter aerodynamic flow interactions  

Microsoft Academic Search

Large circumferentially varying pressure levels produced by aerodynamic flow interactions between downstream stators and struts present a potential noise and stability margin liability in a compression component. These interactions are presently controlled by tailoring the camber and\\/or stagger angles of vanes neighboring the fan frame struts. This paper reports on the design and testing of a unique set of swept

A. R. Wadia; P. N. Szucs; K. L. Gundy-Burlet

1999-01-01

145

Performance of a fractional dc electric motor equipped with plastic bonded Nd2Fe14B stator poles  

NASA Astrophysics Data System (ADS)

Injection molding Nd2Fe14B plastic bonded magnetic material is pressed into the form of cylindrical ring segments in order to investigate its performance when used in the manufacturing of stator poles of fractional power dc motors. Measurements of speed and armature current versus different load torques were performed. The experimental results obtained for stator poles made by three plastic bonded Nd2Fe14B magnetic materials of different densities, are compared to those results obtained by using a pair of typical barium ferrite stator poles. The torque versus speed curves, the obtained mechanical power versus speed and the efficiency of the motor as a function of the speed are presented. The torque speed data in high speeds follow a linear law, as is expected by theory, while at low speeds, below a crossover point, a deviation from this linearity appears. This is attributed to temperature effects. In this work it is shown that in the region of light loads and high speeds, at a certain speed, the injection molded Nd2Fe14B permanent magnet stators produce a higher electromagnetic torque, higher mechanical power, and higher efficiency than the barium ferrite ones.

Nicolaides, G. K.; Atanassova, Y. K.; Ioannides, M. G.; Tsamakis, D. M.; Gamari-Seale, H.

1997-04-01

146

An Excitation-Capacitor-Optimized Dual Stator-Winding Induction Generator With the Static Excitation Controller for Wind Power Application  

Microsoft Academic Search

This paper presents an optimal scheme of excitation capacitor to decrease the capacity of static excitation controller (SEC) for dual stator-winding induction generator (DWIG) system applied in wind power generation. The investigations into reactive excitation power released by the excitation capacitor and SEC il- lustrate that the optimal excitation capacitor is not only related to generator parameters, speed range, and

Feifei Bu; Wenxin Huang; Yuwen Hu; Kai Shi

2011-01-01

147

GENETIC AND ENVIRONMENTAL SOURCES OF VARIATION IN SURVIVAL ON NONNATIVE HOST SPECIES IN THE GENERALIST SEED BEETLE, STATOR LIMBATUS  

Microsoft Academic Search

Humans have introduced organisms into many new and often novel environments. These changes in organism distributions provide us an opportunity to directly observe the ecological and evolutionary processes that influence adaptation. Here we examine the suitability of a variety of introduced legume species, plus several non-host native species, for the development of Stator limbatus larvae. About half of the species

Charles W. Fox; David M. Gordon; Pasano Bojang; Jerry Cook

2006-01-01

148

Numerical-experimental comparison in the simulation of rotor/stator interaction through blade-tip/abradable coating contact  

E-print Network

Numerical-experimental comparison in the simulation of rotor/stator interaction through blade-tip/abradable in the implementation of an abradable liner which improves both the operational safety and the efficiency of modern turbomachines. However, unex- pected abradable wear removal mechanisms were recently observed in experimental

Paris-Sud XI, Université de

149

A COMPLETE STATOR AND ROTOR RESISTANCE IDENTIFIER FOR INDUCTION MOTOR DRIVE USING FUZZY LOGIC AND ARTIFICIAL NEURAL NETWORKS  

Microsoft Academic Search

This paper presents a new method of on-line estimation for the stator and rotor resistances of the induction motor in the indirect vector controlled drive, using fuzzy logic and artificial neural networks. The back propagation algorithm is used for the training of the neural networks for rotor resistance identification. The error between the desired state variable of an induction motor

B. Karanayil; M. F. Rahman; C. Grantham

150

On-line stator and rotor resistance estimation scheme for vector-controlled induction motor drive using artificial neural networks  

Microsoft Academic Search

This paper presents a new method of on-line estimation for the stator and rotor resistances of the induction motor in the indirect vector controlled drive, using artificial neural networks. The back propagation algorithm is used for training of the neural networks. The error between the desired state variable of an induction motor and the actual state variable of a neural

Baburaj Karanayil; Muhammed Fazlur Rahman; Colin Grantham

2003-01-01

151

Online Stator and Rotor Resistance Estimation Scheme Using Artificial Neural Networks for Vector Controlled Speed Sensorless Induction Motor Drive  

Microsoft Academic Search

This paper presents a new method of online estimation for the stator and rotor resistances of the induction motor for speed sensorless indirect vector controlled drives, using artificial neural networks. The error between the rotor flux linkages based on a neural network model and a voltage model is back propagated to adjust the weights of the neural network model for

Baburaj Karanayil; Muhammed Fazlur Rahman; Colin Grantham

2007-01-01

152

PowerformerTM-experiences from the application of extruded solid dielectric cables in the stator winding of rotating machines  

Microsoft Academic Search

ABB has developed a new class of generators, PowerformerTM which are able to deliver electric power directly at transmission voltage levels. This is achieved by changing from traditional stator windings with rectangular conductors to windings with circular conductors based on proven high voltage cable technology with solid extruded dielectric. The paper discusses the concept of Powerformer and some of the

Mats Leijon; Stefan G. Johansson; Fredrik Owman; Stefan Alfredson; Thommy Karlsson; Sture Lindahl; C. Parkegren; S. Thoren

2000-01-01

153

4A-4 UHV Compatible Ultrasonic Motor: Operation keeping UHV and Durability Improvement by Modifying Rotor-Stator Interface  

Microsoft Academic Search

To meet with requirement for actuators that are fully nonmagnetic and compatible to ultrahigh vacuum (UHV), the authors have been developing an ultrasonic motor and researching on various phenomena relating to its operation in UHV. This motor is a cylindrical type or mode rotation type ultrasonic motor, on the stator of which is excited two standing waves. The modes are

Toshiki NIINO; Masahiro Michihata; Yasuhiro ENDO; Shintaro FUNAMI

2006-01-01

154

Stator and Rotor Flux Based Deadbeat Direct Torque Control of Induction Machines. Revision 1  

NASA Technical Reports Server (NTRS)

A new, deadbeat type of direct torque control is proposed, analyzed, and experimentally verified in this paper. The control is based on stator and rotor flux as state variables. This choice of state variables allows a graphical representation which is transparent and insightful. The graphical solution shows the effects of realistic considerations such as voltage and current limits. A position and speed sensorless implementation of the control, based on the self-sensing signal injection technique, is also demonstrated experimentally for low speed operation. The paper first develops the new, deadbeat DTC methodology and graphical representation of the new algorithm. It then evaluates feasibility via simulation and experimentally demonstrates performance of the new method with a laboratory prototype including the sensorless methods.

Kenny, Barbara H.; Lorenz, Robert D.

2002-01-01

155

Magnetic Flux Compression Using Detonation Plasma Armatures and Superconductor Stators: Integrated Propulsion and Power Applications  

NASA Technical Reports Server (NTRS)

This presentation discusses the use of magnetic flux compression for space flight applications as a propulsion and other power applications. The qualities of this technology that make it suitable for spaceflight propulsion and power, are that it has high power density, it can give multimegawatt energy bursts, and terawatt power bursts, it can produce the pulse power for low impedance dense plasma devices (e.g., pulse fusion drivers), and it can produce direct thrust. The issues of a metal vs plasma armature are discussed, and the requirements for high energy output, and fast pulse rise time requires a high speed armature. The plasma armature enables repetitive firing capabilities. The issues concerning the high temperature superconductor stator are also discussed. The concept of the radial mode pulse power generator is described. The proposed research strategy combines the use of computational modeling (i.e., magnetohydrodynamic computations, and finite element modeling) and laboratory experiments to create a demonstration device.

Litchford, Ron; Robertson, Tony; Hawk, Clark; Turner, Matt; Koelfgen, Syri

1999-01-01

156

Analysis on accuracy improvement of rotor-stator rubbing localization based on acoustic emission beamforming method.  

PubMed

This paper attempts to introduce an improved acoustic emission (AE) beamforming method to localize rotor-stator rubbing fault in rotating machinery. To investigate the propagation characteristics of acoustic emission signals in casing shell plate of rotating machinery, the plate wave theory is used in a thin plate. A simulation is conducted and its result shows the localization accuracy of beamforming depends on multi-mode, dispersion, velocity and array dimension. In order to reduce the effect of propagation characteristics on the source localization, an AE signal pre-process method is introduced by combining plate wave theory and wavelet packet transform. And the revised localization velocity to reduce effect of array size is presented. The accuracy of rubbing localization based on beamforming and the improved method of present paper are compared by the rubbing test carried on a test table of rotating machinery. The results indicate that the improved method can localize rub fault effectively. PMID:23735348

He, Tian; Xiao, Denghong; Pan, Qiang; Liu, Xiandong; Shan, Yingchun

2014-01-01

157

Stator and Rotor Flux Based Deadbeat Direct Torque Control of Induction Machines  

NASA Technical Reports Server (NTRS)

A new, deadbeat type of direct torque control is proposed, analyzed, and experimentally verified in this paper. The control is based on stator and rotor flux as state variables. This choice of state variables allows a graphical representation which is transparent and insightful. The graphical solution shows the effects of realistic considerations such as voltage and current limits. A position and speed sensorless implementation of the control, based on the self-sensing signal injection technique, is also demonstrated experimentally for low speed operation. The paper first develops the new, deadbeat DTC methodology and graphical representation of the new algorithm. It then evaluates feasibility via simulation and experimentally demonstrates performance of the new method with a laboratory prototype including the sensorless methods.

Kenny, Barbara H.; Lorenz, Robert D.

2001-01-01

158

Flow visualization study of the horseshoe vortex in a turbine stator cascade  

NASA Technical Reports Server (NTRS)

Flow visualization techniques were used to show the behavior of the horseshoe vortex in a large scale turbine stator cascade. Oil drops on the end wall surface flowed in response to local shear stresses, indicating the limiting flow streamlines at the surface. Smoke injected into the flow and photographed showed time averaged flow behavior. Neutrally bouyant helium filled soap bubbles followed the flow and showed up on photographs as streaks, indicating the paths followed by individual fluid particles. Preliminary attempts to control the vortex were made by injecting air through control jets drilled in the end wall near the vane leading edge. Seventeen different hole locations were tested, one at a time, and the effect of the control jets on the path follwed by smoke in the boundary layer was recorded photographically.

Gaugler, R. E.; Russell, L. M.

1982-01-01

159

Flagella stator homologs function as motors for myxobacterial gliding motility by moving in helical trajectories  

PubMed Central

Many bacterial species use gliding motility in natural habitats because external flagella function poorly on hard surfaces. However, the mechanism(s) of gliding remain elusive because surface motility structures are not apparent. Here, we characterized the dynamics of the Myxococcus xanthus gliding motor protein AglR, a homolog of the Escherichia coli flagella stator protein MotA. We observed that AglR decorated a helical structure, and the AglR helices rotated when cells were suspended in liquid or when cells moved on agar surfaces. With photoactivatable localization microscopy, we found that single molecules of AglR, unlike MotA/MotB, can move laterally within the membrane in helical trajectories. AglR slowed down transiently at gliding surfaces, accumulating in clusters. Our work shows that the untethered gliding motors of M. xanthus, by moving within the membrane, can transform helical motion into linear driving forces that push against the surface. PMID:23576734

Nan, Beiyan; Bandaria, Jigar N.; Moghtaderi, Amirpasha; Sun, Im-Hong; Yildiz, Ahmet; Zusman, David R.

2013-01-01

160

BRIEF COMMUNICATION: Piezoelectric ultrasonic resonant motor with stator diameter less than 250 µm: the Proteus motor  

NASA Astrophysics Data System (ADS)

Minimally invasive and in vivo surgery is limited by the ability to provide controllable and powerful motion at scales appropriate for navigation within the human body. A motor for in vivo microbot propulsion is presented with a stator diameter of phi250 µm, demonstrating the potential to directly drive a flagellum for swimming at up to 1295 rpm with a torque of 13 nN m. The motor uses coupled axial-torsional vibration at 652-682 kHz in a helically cut structure excited by a thickness-polarized piezoelectric element. The output power is 4.25 µW, on the order of what is necessary to navigate small human arteries.

Watson, B.; Friend, J.; Yeo, L.

2009-02-01

161

Experimental Evaluation of Cermet Turbine Stator Blades for Use at Elevated Gas Temperatures  

NASA Technical Reports Server (NTRS)

The suitability of cermets for turbine stator blades of a modified turbojet engine was determined at an average turbine-inlet-gas temperature of 2000 F. Such an increase in temperature would yield a premium in thrust from a service engine. Because the cermet blades require no cooling, all the available compressor bleed air could be used to cool a turbine made from conventional ductile alloys. Cermet blades were first run in 100-hour endurance tests at normal gas temperatures in order to evaluate two methods for mounting them. The elevated gas-temperature test was then run using the method of support considered best for high-temperature operation. After 52 hours at 2000 F, one of the group of four cermet blades fractured probably because of end loads resulting from thermal distortion of the spacer band of the nozzle diaphragm. Improved design of a service engine would preclude this cause of premature failure.

Chiarito, Patrick T.; Johnston, James R.

1959-01-01

162

Redesign and cascade tests of a supercritical controlled diffusion stator blade-section  

NASA Technical Reports Server (NTRS)

A supercritical stator blade section, previously tested in cascade, and characterized by a flat-roof-top suction surface Mach number distribution, has been redesigned and retested. At near design conditions, the losses and air turning were improved over the original blade by 50 percent and 7 percent, respectively. The key element in the improved performance was a small blade reshaping. This produced a continuous flow acceleration over the first one-third chord of the suction surface which successfully prevented a premature laminar separation bubble. Several recently available inviscid analysis codes and one fully viscous (Navier-Stokes) analysis code were used in the redesign process. The validity of these codes was enhanced by the test results. Previously announced in STAR as N84-22533

Schmidt, J. F.; Gelder, T. F.; Donovan, L. F.

1984-01-01

163

Redesign and cascade tests of a supercritical controlled diffusion stator blade-section  

NASA Technical Reports Server (NTRS)

A supercritical stator blade section, previously tested in cascade, and characterized by a flat-roof-top suction surface Mach number distribution, has been redesigned and retested. At near design conditions, the losses and air turning were improved over the original blade by 50 percent and 7 percent respectively. The key element in the improved performance was a small blade reshaping. This produced a continuous flow acceleration over the first one-third chord of the suction surface which successfully prevented a premature laminar separation bubble. Several recently available inviscid analysis and one fully viscous (Navier-Stokes) analysis code were used in the redesign process. The validity of these codes was enhanced by the test results.

Schmidt, J. F.; Gelder, T. F.; Donovan, L. F.

1984-01-01

164

An explicit Runge-Kutta method for unsteady rotor/stator interaction  

NASA Technical Reports Server (NTRS)

A quasi-three-dimensional rotor/stator analysis has been developed for blade-to-blade flows in turbomachinery. The analysis solves the unsteady Euler or thin-layer Navier-Stokes equations in a body-fitted coordinate system. It accounts for the effects of rotation, radius change, and stream-surface thickness. The Baldwin-Lomax eddy-viscosity model is used for turbulent flows. The equations are integrated in time using a four-stage Runge-Kutta scheme with a constant timestep. Results are shown for the first stage of the Space Shuttle Main Engine high pressure fuel turbopump. Euler and Navier-Stokes results are compared on the scaled single- and multi-passage machine. The method is relatively fast and the quasi-three-dimensional formulation is applicable to a wide range of turbomachinery geometries.

Jorgenson, Philip C. E.; Chima, Rodrick V.

1988-01-01

165

Transient technique for measuring heat transfer coefficients on stator airfoils in a jet engine environment  

NASA Technical Reports Server (NTRS)

A transient technique was used to measure heat transfer coefficients on stator airfoils in a high-temperature annular cascade at real engine conditions. The transient response of thin film thermocouples on the airfoil surface to step changes in the gas stream temperature was used to determine these coefficients. In addition, gardon gages and paired thermocouples were also utilized to measure heat flux on the airfoil pressure surface at steady state conditions. The tests were conducted at exit gas stream Reynolds numbers of one-half to 1.9 million based on true chord. The results from the transient technique show good comparison with the steady-state results in both trend and magnitude. In addition, comparison is made with the STAN5 boundary layer code and shows good comparison with the trends. However, the magnitude of the experimental data is consistently higher than the analysis.

Gladden, H. J.; Proctor, M. P.

1985-01-01

166

Fault diagnosis of motor drives using stator current signal analysis based on dynamic time warping  

NASA Astrophysics Data System (ADS)

Electrical motor stator current signals have been widely used to monitor the condition of induction machines and their downstream mechanical equipment. The key technique used for current signal analysis is based on Fourier transform (FT) to extract weak fault sideband components from signals predominated with supply frequency component and its higher order harmonics. However, the FT based method has limitations such as spectral leakage and aliasing, leading to significant errors in estimating the sideband components. Therefore, this paper presents the use of dynamic time warping (DTW) to process the motor current signals for detecting and quantifying common faults in a downstream two-stage reciprocating compressor. DTW is a time domain based method and its algorithm is simple and easy to be embedded into real-time devices. In this study DTW is used to suppress the supply frequency component and highlight the sideband components based on the introduction of a reference signal which has the same frequency component as that of the supply power. Moreover, a sliding window is designed to process the raw signal using DTW frame by frame for effective calculation. Based on the proposed method, the stator current signals measured from the compressor induced with different common faults and under different loads are analysed for fault diagnosis. Results show that DTW based on residual signal analysis through the introduction of a reference signal allows the supply components to be suppressed well so that the fault related sideband components are highlighted for obtaining accurate fault detection and diagnosis results. In particular, the root mean square (RMS) values of the residual signal can indicate the differences between the healthy case and different faults under varying discharge pressures. It provides an effective and easy approach to the analysis of motor current signals for better fault diagnosis of the downstream mechanical equipment of motor drives in the time domain in comparison with conventional FT based methods.

Zhen, D.; Wang, T.; Gu, F.; Ball, A. D.

2013-01-01

167

Two-dimensional cold-air cascade study of a film-cooled turbine stator blade. 1: Experimental results of pressure-surface film cooling tests  

NASA Technical Reports Server (NTRS)

The effect of film coolant ejection from the pressure side of a stator blade was determined in a two-dimensional cascade. Stator exit surveys were made for each of six rows of coolant holes. Successive multirow tests were made with two, three, four, five, and six rows of coolant holes open. The results of the multirow tests are compared with the predicted multirow performance obtained by adding the single-row data. Results are presented in terms of stator primary-air efficiency as a function of coolant fraction.

Moffitt, T. P.; Prust, H. W., Jr.; Bartlett, W. M.

1974-01-01

168

Cold-air performance of free power turbine designed for 112-kilowatt automotive gas-turbine engine. III. Effect of stator-vane end clearances on performance  

Microsoft Academic Search

An experimental investigation of a free power turbine designed for a 112-kW, automotive, gas-turbine engine was made to determine the penalty in performance due to the stator-vane end clearances. Tests were made over a range of mean section stator-vane angles from 26° to 50° with the vane end clearances filled. These results are compared with test results of the same

M. G. Kofskey; K. L. McLallin

1978-01-01

169

Design and Analyses of a Coreless-Stator-Type Bearingless Motor\\/Generator for Clean Energy Generation and Storage Systems  

Microsoft Academic Search

This paper presents a design for a new bearingless motor\\/generator suitable for use in clean energy generation and storage systems. The machine is an outer-rotor type with a coreless stator. By using this type of bearingless drive in an energy generation or storage system, it is possible to obtain high efficiency, maintenance-free operation, and a long life cycle. In this

M. Ooshima; S. Kitazawa; A. Chiba; T. Fukao; D. G. Dorrell

2006-01-01

170

Mixed eccentricity diagnosis in Inverter-Fed Induction Motors via the Adaptive Slope Transform of transient stator currents  

NASA Astrophysics Data System (ADS)

This paper researches the detection of mixed eccentricity in Inverter-Fed Induction Motors. The classic FFT method cannot be applied when the stator current captured is not in steady state, which is very common in these motors. Therefore, a transform able to detect the time-frequency evolutions of the components present in the transient signal captured must be applied. In order to optimize the result, a method to calculate the theoretical time-frequency evolution of the stator current components is presented, using only the captured current. This previously obtained information enables the use of the proposed transform: the Adaptive Slope Transform, based on appropriately choosing the atom slope in each point analyzed. Thanks to its adaptive characteristics, the time-frequency evolution of the main components in a stator transient current is traced precisely and with high detail in the 2D time-frequency plot obtained. As a consequence, the time-frequency plane characteristic patterns produced by the Eccentricity Related Harmonics are easily and clearly identified enabling a reliable diagnosis. Moreover, the problem of quantifying the presence of the fault is solved presenting a simple and easy to apply method. The transform capabilities have been shown successfully diagnosing an Inverter-Fed Induction Motor with mixed eccentricity during a startup, a decrease in the assigned frequency, and a load variation with and without slip compensation.

Pons-Llinares, J.; Antonino-Daviu, J.; Roger-Folch, J.; Moríñigo-Sotelo, D.; Duque-Pérez, O.

2014-10-01

171

Periodic transition on an axial compressor stator: Incidence and clocking effects. Part 2: Transition onset predictions  

SciTech Connect

Transition onset observations from a 1.5-stage axial compressor outlet stator presented in Part 1 of this paper are compared with the predictions of conventional transition correlations applied in a quasi-steady manner. The viscous/inviscid interaction code MISES is used to predict the blade surface pressure distributions, and boundary layer development. The temporal variation in transition onset is then predicted using ensemble-averaged free-stream turbulence data from the compressor measurements. This simple procedure captures most significant features of the complex transition process on the compressor, and is clearly superior to fixed transition models based on long-term average free-stream turbulence levels. Parallel computations for both natural and bypass transition modes indicate that the natural transition mode tends to dominate on the compressor. This is at variance with turbine airfoil experience, where bypass transition is clearly more important. Comparison of prediction and experiment highlights the significance of leading edge potential flow interactions in promoting periodic wake-induced transition. Viscous/inviscid interactions in the neighborhood of transition can also have an important influence on boundary layer stability and separation phenomena.

Solomon, W.J. [General Electric Aircraft Engines, Cincinnati, OH (United States); Walker, G.J.; Hughes, J.D. [Univ. of Tasmania, Hobart (Australia). School of Engineering

1999-07-01

172

Compressible simulation of rotor-stator interaction in pump-turbines  

NASA Astrophysics Data System (ADS)

This work investigates the influence of water compressibility on pressure pulsations induced by rotor-stator interaction (RSI) in hydraulic machinery, using the commercial CFD solver ANSYS-CFX. A pipe flow example with harmonic velocity excitation at the inlet plane is simulated using different grid densities and time step sizes. Results are compared with a validated code for hydraulic networks (SIMSEN). Subsequently, the solution procedure is applied to a simplified 2.5-dimensional pump-turbine configuration in model scale with an adapted speed of sound. Pressure fluctuations are compared with numerical and experimental data based on prototype scale. The good agreement indicates that the scaling of acoustic effects with an adapted speed of sound works well. Finally, the procedure is applied to a 3-dimensional pump configuration in model scale. Pressure fluctuations are compared with results from prototype measurements. Compared to incompressible computations, compressible simulations provide similar pressure fluctuations in vaneless space, but pressure fluctuations in spiral case and penstock may be much higher. With respect to pressure fluctuation amplitudes along the centerline of runner channels, incompressible solutions exhibit a linear decrease while compressible solutions exhibit sinusoidal distributions with maximum values at half the channel length, coinciding with analytical solutions of one-dimensional acoustics.

Yan, J.; Koutnik, J.; Seidel, U.; Hübner, B.

2010-08-01

173

Rotor-stator contact dynamics using a non-ideal drive—Theoretical and experimental aspects  

NASA Astrophysics Data System (ADS)

The possible contact between rotor and stator is considered a serious malfunction that may lead to catastrophic failure. Rotor rub is seen as a secondary phenomenon caused by a primary source, i.e. sudden mass unbalance, instabilities generated by aerodynamic and hydrodynamic forces in seals and bearings among others. The contact event gives rise to normal and friction forces exerted on the rotor at impact events. The friction force plays a significant role by transferring some rotational energy of the rotor to lateral motion. A mathematical model has been developed to capture this for a conventional backup annular guide setup. It is reasonable to superpose an impact condition to the rub, where the rotor spin energy can be fully transformed into rotor lateral movements. Using a nonideal drive, i.e. an electric motor without any kind of velocity feedback control, it is even possible to stop the rotor spin under rubbing conditions. All the rotational energy will be transformed in a kind of "self-excited" rotor lateral vibration with repeated impacts against the housing. This paper studies the impact motion of a rotor impacting a conventional backup annular guide for the case of dry and lubricated inner surface of the guide. For the dry surface case, the experimental and numerical analysis shows that the rotational energy is fully transformed into lateral motion and the rotor spin is stopped. Based on this study this paper proposes a new unconventional backup bearing design in order to reduce the rub related severity in friction and center the rotor at impact events. The analysis shows that the rotor at impacts is forced to the center of the backup bearing and the lateral motion is mitigated. As a result of this, the rotor spin is kept constant.

Lahriri, Said; Weber, Hans I.; Santos, Ilmar F.; Hartmann, Henning

2012-09-01

174

Measurements of the unsteady flow field within the stator row of a transonic axial-flow fan. Part 2: Results and discussion  

NASA Technical Reports Server (NTRS)

Unsteady velocity field measurements made within the stator row of a transonic axial-flow fan are presented. Measurements were obtained at midspan for two different stator blade rows using a laser anemometer. The first stator row consists of double circular-arc airfoils with a solidity of 1.68. The second features controlled-diffusion airfoils with a solidity of 0.85. Both were tested at design-speed peak efficiency conditions. In addition, the controlled-diffusion stator was also tested at near stall conditions. The procedures developed here are used to identify the rotor wake generated and unresolved unsteadiness from the velocity measurements (rotor wake generated unsteadiness refers to the unsteadiness generated by the rotor wake velocity deficit and unresolved unsteadiness refers to all remaining unsteadiness which contributes to the spread in the distribution of velocities such as vortex shedding, turbulence, etc.). Auto and cross correlations of these unsteady velocity fluctuations are presented to show their relative magnitude and spatial distributions. Amplification and attenuation of both rotor wake generated and unresolved unsteadiness are shown to occur within the stator blade passage.

Hathaway, M. D.; Suder, K. L.; Okiishi, T. H.; Strazisar, A. J.; Adamczyk, J. J.

1987-01-01

175

Velocity surveys in a turbine stator annular-cascade facility using laser Doppler techniques. [flow measurement and flow characteristics  

NASA Technical Reports Server (NTRS)

A laser Doppler velocimeter (LDV) was used to determine the flow conditions downstream of an annular cascade of stator blades operating at an exit critical velocity ratio of 0.87. Two modes of LDV operation (continuous scan and discrete point) were investigated. Conventional pressure probe measurements were also made for comparison with the LDV results. Biasing errors that occur in the LDV measurement of velocity components were also studied. In addition, the effect of pressure probe blockage on the flow conditions was determined with the LDV. Photographs and descriptions of the test equipment used are given.

Goldman, L. J.; Seasholtz, R. G.; Mclallin, K. L.

1976-01-01

176

Influence of control strategy on stator and rotor losses in high-speed permanent magnet brushless motors  

NASA Astrophysics Data System (ADS)

The stator iron loss and rotor eddy current loss which results in a high-speed permanent magnet brushless motor when operated in brushless dc and ac modes, on both open-circuit and at rated load, with four different current control strategies, is investigated by finite element analysis. It has highlighted the significant influence of the phase current wave form. It has also shown that, on load, the rotor eddy current loss can be the dominant loss component, particularly in brushless dc mode.

Zhu, Z. Q.; Chen, Y.; Howe, D.

2005-05-01

177

A novel indicator of stator winding inter-turn fault in induction motor using infrared thermal imaging  

NASA Astrophysics Data System (ADS)

In this paper, a novel online and non-destructive algorithm is proposed to detect inter-turn short circuit faults in the stator windings of an induction motor. This fault detection algorithm is based on the features extracted from infrared images taken from the hottest region of the motor surface. Feature extraction method from infrared thermal images has been developed based on histogram of temperature profile, correlation between fault severity and the hottest region on the motor body, and comparison with healthy motor features. Experiments are conducted to demonstrate the effectiveness of the proposed method using a 2-hp induction motor.

Eftekhari, M.; Moallem, M.; Sadri, S.; Hsieh, Min-Fu

2013-11-01

178

Analysis and testing for rotordynamic coefficients of turbulent annular seals with different, directionally-homogeneous surface-roughness treatment for rotor and stator elements  

NASA Technical Reports Server (NTRS)

A combined analytical-computational method has been developed to calculate the transient pressure field and rotordynamic coefficients for high-pressure annular seals. The solution procedure applies to constant-clearance or the convergent tapered geometries of multistage centrifugal pumps which may have different surface roughness conditions on the stator and rotor seal elements. In experimental calculations with the method, the turbulent equations of Hirs (1973) are modified slightly to account for different surface roughness conditions, and a perturbation analysis is employed to develop zeroth and first order perturbation equations. Zeroth equations are also used to define both the leakage and circumferential flow due to shear stresses around the stator and rotor surfaces. The solution to analytical equations for four different surface roughnesses confirm the predicted net damping for the seals. A round-holed stator pattern yielded the highest net damping and lowest leakage of all the seals tested.

Childs, D. W.; Kim, C.-H.

1984-01-01

179

Impact of clocking on the aero-thermodynamics of a second stator tested in a one and a half stage HP turbine  

NASA Astrophysics Data System (ADS)

This paper focuses on the experimental investigation of the time-averaged and time-accurate aero-thermodynamics of a second stator tested in a 1.5 stage high-pressure turbine. The effect of clocking on aerodynamic and heat transfer are investigated. Tests are performed under engine representative conditions in the VKI compression tube CT3. The test program includes four different clocking positions, i.e. relative pitch-wise positions between the first and the second stator. Probes located upstream and downstream of the second stator provide the thermodynamic conditions of the flow field. On the second stator airfoil, measurements are taken around the blade profile at 15, 50 and 85% span with pressure sensors and thin-film gauges. Both time-averaged and time-resolved aspects of the flow field are addressed. Regarding the time-averaged results, clocking effects are mainly observed within the leading edge region of the second stator, the largest effects being observed at 15% span. The surface static pressure distribution is changed locally, hence affecting the overall airfoil performance. For one clocking position, the thermal load of the airfoil is noticeably reduced. Pressure fluctuations are attributed to the passage of the upstream transonic rotor and its associated pressure gradients. The pattern of these fluctuations changes noticeably as a function of clocking. The time-resolved variations of heat flux and static pressure are analyzed together showing that the major effect is due to a potential interaction. The time-resolved pressure distribution integrated along the second stator surface yields the unsteady forces on the vane. The magnitude of the unsteady force is very dependent on the clocking position.

Billiard, N.; Paniagua, Guillermo; Dénos, R.

2008-06-01

180

Studying the development of asynchronous rolling of the rotor over the stator with the turbine unit protection systems having different response times  

NASA Astrophysics Data System (ADS)

The possibility to stabilize the developing asynchronous rolling of the rotor over the stator under the conditions of power unit protections coming in action with different response times is considered. Asynchronous rolling of the rotor over the stator may develop when the rotating rotor comes in contact with the stator at high amplitudes of vibration caused by an abrupt loss of rotor balancing, by forced or self-excited vibration of the rotor, and by other factors. The danger of asynchronous rolling is connected with almost instantaneous development of self-excited vibration of the rotor when it comes in contact with the stator and with the rotor vibration amplitudes and forces of interaction between the rotor and stator dangerous for the turbine unit integrity. It is assumed that the turbine unit protection systems come in action after the arrival of signal of exceeding the permissible vibration level and produce commands to disconnect the generator from the grid, and to stop the supply of working fluid into the flow path, due to which an accelerating torque ceases to act on the turbine unit shaft. The protection system response speed is determined by a certain time t = ABtime that is taken for its components to come in action from the commencement of the event (application of the signal) to closure of the stop valves. The time curves of the main rolling parameters as functions of the ABtime value are presented. It is shown that the response time of existing protection systems is not sufficient for efficiently damping the rolling phenomenon, although the use of an electrical protection system (with the response time equal to 0.40-0.45 s) may have a positive effect on stabilizing the vibration amplitudes to a certain extent during the rolling and on smoothing its dangerous consequences. The consequences of rotor rolling over the stator can be efficiently mitigated by increasing the energy losses in the rotor-stator system (especially in the stator) and by fulfilling the recommendations of the machinery unit catastrophe prevention system.

Shatokhin, V. F.

2014-07-01

181

Reliability and Confidence Interval Analysis of a CMC Turbine Stator Vane  

NASA Technical Reports Server (NTRS)

High temperature ceramic matrix composites (CMC) are being explored as viable candidate materials for hot section gas turbine components. These advanced composites can potentially lead to reduced weight, enable higher operating temperatures requiring less cooling and thus leading to increased engine efficiencies. However, these materials are brittle and show degradation with time at high operating temperatures due to creep as well as cyclic mechanical and thermal loads. In addition, these materials are heterogeneous in their make-up and various factors affect their properties in a specific design environment. Most of these advanced composites involve two- and three-dimensional fiber architectures and require a complex multi-step high temperature processing. Since there are uncertainties associated with each of these in addition to the variability in the constituent material properties, the observed behavior of composite materials exhibits scatter. Traditional material failure analyses employing a deterministic approach, where failure is assumed to occur when some allowable stress level or equivalent stress is exceeded, are not adequate for brittle material component design. Such phenomenological failure theories are reasonably successful when applied to ductile materials such as metals. Analysis of failure in structural components is governed by the observed scatter in strength, stiffness and loading conditions. In such situations, statistical design approaches must be used. Accounting for these phenomena requires a change in philosophy on the design engineer s part that leads to a reduced focus on the use of safety factors in favor of reliability analyses. The reliability approach demands that the design engineer must tolerate a finite risk of unacceptable performance. This risk of unacceptable performance is identified as a component's probability of failure (or alternatively, component reliability). The primary concern of the engineer is minimizing this risk in an economical manner. The methods to accurately determine the service life of an engine component with associated variability have become increasingly difficult. This results, in part, from the complex missions which are now routinely considered during the design process. These missions include large variations of multi-axial stresses and temperatures experienced by critical engine parts. There is a need for a convenient design tool that can accommodate various loading conditions induced by engine operating environments, and material data with their associated uncertainties to estimate the minimum predicted life of a structural component. A probabilistic composite micromechanics technique in combination with woven composite micromechanics, structural analysis and Fast Probability Integration (FPI) techniques has been used to evaluate the maximum stress and its probabilistic distribution in a CMC turbine stator vane. Furthermore, input variables causing scatter are identified and ranked based upon their sensitivity magnitude. Since the measured data for the ceramic matrix composite properties is very limited, obtaining a probabilistic distribution with their corresponding parameters is difficult. In case of limited data, confidence bounds are essential to quantify the uncertainty associated with the distribution. Usually 90 and 95% confidence intervals are computed for material properties. Failure properties are then computed with the confidence bounds. Best estimates and the confidence bounds on the best estimate of the cumulative probability function for R-S (strength - stress) are plotted. The methodologies and the results from these analyses will be discussed in the presentation.

Murthy, Pappu L. N.; Gyekenyesi, John P.; Mital, Subodh K.

2008-01-01

182

Design and testing of swept and leaned outlet guide vanes to reduce stator-strut-splitter aerodynamic flow interactions  

SciTech Connect

Large circumferentially varying pressure levels produced by aerodynamic flow interactions between downstream stators and struts present a potential noise and stability margin liability in a compression component. These interactions are presently controlled by tailoring the camber and/or stagger angles of vanes neighboring the fan frame struts. This paper reports on the design and testing of a unique set of swept and leaned fan outlet guide vanes (OGVs) that do not require this local tailoring even though the OGVs are closely coupled with the fan frame struts and splitter to reduce engine length. The swept and leaned OGVs not only reduce core-duct diffusion, but they also reduce the potential flow interaction between the stator and the strut relative to that produced by conventional radial OGVs. First, the design of the outlet guide vanes using a single blade row three-dimensional viscous flow analysis is outlined. Next, a two-dimensional potential flow analysis was used for the coupled OGV-frame system to obtain a circumferentially nonuniform stator stagger angle distribution to reduce the upstream static pressure disturbance further. Recognizing the limitations of the two-dimensional potential flow analysis for this highly three-dimensional set of leaned OGVs, as a final evaluation of the OGV-strut system design, a full three-dimensional viscous analysis of a periodic circumferential sector of the OGVs, including the fan frame struts and splitter, was performed. The computer model was derived from a NASA-developed code used in simulating the flow field for external aerodynamic applications with complex geometries. The tree-dimensional coupled OGV-frame analysis included the uniformly staggered OGV configuration and the variably staggered OGV configuration determined by the two-dimensional potential flow analysis. Contrary to the two-dimensional calculations, the tree-dimensional analysis revealed significant flow problems with the variable staggered OGV configuration and showed less upstream flow nonuniformity with the uniformly staggered OGV configuration. The flow redistribution in both the radial and tangential directions, captured fully only in the three-dimensional analysis, was identified as the prime contributor to the lower flow nonuniformity with the uniformly staggered OGV configuration. The coupled three-dimensional analysis was also used to validate the design at off-design conditions. Engine test performance and stability measurements with both uniformly and variably staggered OGV configurations with and without the presence of inlet distortion confirmed the conclusions from the three-dimensional analysis.

Wadia, A.R.; Szucs, P.N. [GE Aircraft Engines, Cincinnati, OH (United States); Gundy-Burlet, K.L. [NASA Ames Research Center, Moffet Field, CA (United States)

1999-07-01

183

Unsteady Flows in a Single-Stage Transonic Axial-Flow Fan Stator Row. Ph.D. Thesis - Iowa State Univ.  

NASA Technical Reports Server (NTRS)

Measurements of the unsteady velocity field within the stator row of a transonic axial-flow fan were acquired using a laser anemometer. Measurements were obtained on axisymmetric surfaces located at 10 and 50 percent span from the shroud, with the fan operating at maximum efficiency at design speed. The ensemble-average and variance of the measured velocities are used to identify rotor-wake-generated (deterministic) unsteadiness and turbulence, respectively. Correlations of both deterministic and turbulent velocity fluctuations provide information on the characteristics of unsteady interactions within the stator row. These correlations are derived from the Navier-Stokes equation in a manner similar to deriving the Reynolds stress terms, whereby various averaging operators are used to average the aperiodic, deterministic, and turbulent velocity fluctuations which are known to be present in multistage turbomachines. The correlations of deterministic and turbulent velocity fluctuations throughout the axial fan stator row are presented. In particular, amplification and attenuation of both types of unsteadiness are shown to occur within the stator blade passage.

Hathaway, Michael D.

1986-01-01

184

Turbine blade platform film cooling with simulated stator-rotor purge flow with varied seal width and upstream wake with vortex  

E-print Network

The turbine blade platform can be protected from hot mainstream gases by injecting cooler air through the gap between stator and rotor. The effectiveness of this film cooling method depends on the geometry of the slot, the quantity of injected air...

Blake, Sarah Anne

2009-05-15

185

Rotor power losses in planar radial magnetic bearings -- Effects of number of stator poles, air gas thickness, and magnetic flux density  

Microsoft Academic Search

Rotor power losses in magnetic bearings cannot be accurately calculated at this time because of the complexity of the magnetic field distribution and several other effects. The losses are due to eddy currents, hysteresis, and windage. This paper presents measured results in radial magnetic bearing configurations with eight pole and 16 pole stators and two laminated rotors. Two different air

P. E. Allaire; M. E. F. Kasarda; L. K. Fujita

1999-01-01

186

A numerical procedure to determine blade temperature of cooled stator blades in gas turbines: A numerical and experimental comparison  

SciTech Connect

The continuing need to improve both efficiency and specific power of gas turbines requires progressively increasing turbine inlet temperatures and blade cooling efficiency. This paper presents a blade cooling simulation code for gas turbine stator blades analysis. A comparison between the predictions of simulation and the experimental data of the external nozzle temperatures of a small heavy duty gas turbine is presented. The simulation code allows for several cooling techniques on the basis of different solutions combined (as they often are) on the same blade. The cooling model considered is simplified: the limitation in the accuracy of the results is far overcome by the simplicity and versatility of the approach. A two-dimensional Navier Stokes simulation of film cooling is also compared with a correlation approach.

Carcasci, C.; Facchini, B. [Univ. of Florence (Italy). Dept. of Energy Engineering; Corradini, U. [Nuovo Pignone S.p.A., Florence (Italy)

1994-12-31

187

Performance improvements of a subsonic axial-flow compressor by means of a non-axisymmetric stator hub end-wall  

NASA Astrophysics Data System (ADS)

This paper deals with the application of a non-axisymmetric hub end-wall on the stator of a single stage high subsonic axial-flow compressor. In order to obtain a state-of-the-art stator non-axisymmetric hub end-wall configuration fulfilling the requirements for higher efficiency and total pressure ratio, an automated multi-objective optimizer was used, in conjunction with 3D-RANS-flow simulations. For the purpose of quantifying the effect of the optimal stator non axis-symmetric hub contouring on the compressor performance and its effects on the subsonic axial-flow compressor stator end-wall flow field structure, the coupled flow of the compressor stage with the baseline, axisymmetric and the non-axisymmetric stator hub end-wall was simulated with a state-of-theart multi-block flow 3D CFD solver. Based on the CFD simulations, the optimal compressor hub end-wall configuration is expected to increase the peak efficiency by approximately 2.04 points and a slight increase of the total pressure ratio. Detailed analyses of the numerical flow visualization at the hub have uncovered the different hub flow topologies between the cases with axisymmetric and non-axisymmetric hub end-walls. It was found that that the primary performance enhancement afforded by the non-axisymmetric hub end-wall is a result of the end-wall flow structure modification. Compared to the smooth wall case, the non-axisymmetric hub end-wall can reduce the formation and development of in-passage secondary flow by aerodynamic loading redistribution.

Zhang, Xuefeng; Lu, Xingen; Zhu, Junqiang

2013-12-01

188

Understanding the apparent stator-rotor connections in the rotary ATPase family using coarse-grained computer modeling.  

PubMed

Advances in structural biology, such as cryo-electron microscopy (cryo-EM) have allowed for a number of sophisticated protein complexes to be characterized. However, often only a static snapshot of a protein complex is visualized despite the fact that conformational change is frequently inherent to biological function, as is the case for molecular motors. Computer simulations provide valuable insights into the different conformations available to a particular system that are not accessible using conventional structural techniques. For larger proteins and protein complexes, where a fully atomistic description would be computationally prohibitive, coarse-grained simulation techniques such as Elastic Network Modeling (ENM) are often employed, whereby each atom or group of atoms is linked by a set of springs whose properties can be customized according to the system of interest. Here we compare ENM with a recently proposed continuum model known as Fluctuating Finite Element Analysis (FFEA), which represents the biomolecule as a viscoelastic solid subject to thermal fluctuations. These two complementary computational techniques are used to answer a critical question in the rotary ATPase family; implicit within these motors is the need for a rotor axle and proton pump to rotate freely of the motor domain and stator structures. However, current single particle cryo-EM reconstructions have shown an apparent connection between the stators and rotor axle or pump region, hindering rotation. Both modeling approaches show a possible role for this connection and how it would significantly constrain the mobility of the rotary ATPase family. Proteins 2014; 82:3298-3311. © 2014 The Authors. Proteins: Structure, Function, and Bioinformatics Published by Wiley Periodicals, Inc. PMID:25174610

Richardson, Robin A; Papachristos, Konstantinos; Read, Daniel J; Harlen, Oliver G; Harrison, Michael; Paci, Emanuele; Muench, Stephen P; Harris, Sarah A

2014-12-01

189

Rotor/Stator interactions of the epsilon subunit in Escherichia coli ATP synthase and implications for enzyme regulation.  

PubMed

The H(+)-translocating F(0)F(1)-ATP synthase of Escherichia coli functions as a rotary motor, coupling the transmembrane movement of protons through F(0) to the synthesis of ATP by F(1). Although the epsilon subunit appears to be tightly associated with the gamma subunit in the central stalk region of the rotor assembly, several studies suggest that the C-terminal domain of epsilon can undergo significant conformational change as part of a regulatory process. Here we use disulfide cross-linking of substituted cysteines on functionally coupled ATP synthase to characterize interactions of epsilon with an F(0) component of the rotor (subunit c) and with an F(1) component of the stator (subunit beta). Oxidation of the engineered F(0)F(1) causes formation of two disulfide bonds, betaD380C-S108C epsilon and epsilonE31C-cQ42C, to give a beta-epsilon-c cross-linked product in high yield. The results demonstrate the ability of epsilon to span the central stalk region from the surface of the membrane (epsilon-c) to the bottom of F(1) (beta-epsilon) and suggest that the conformation detected here is distinct from both the "closed" state seen with isolated epsilon (Uhlin, U., Cox, G. B., and Guss, J. M. (1997) Structure 5, 1219-1230) and the "open" state seen in a complex with a truncated form of the gamma subunit (Rodgers, A. J., and Wilce, M. C. (2000) Nat. Struct. Biol. 7, 1051-1054). The kinetics of beta-epsilon and epsilon-c cross-linking were studied separately using F(0)F(1) containing one or the other matched cysteine pair. The rate of cross-linking at the epsilon/c (rotor/rotor) interface is not influenced by the type of nucleotide added. In contrast, the rate of beta-epsilon cross-linking is fastest under ATP hydrolysis conditions, intermediate with MgADP, and slowest with MgAMP-PNP. This is consistent with a regulatory role for a reversible beta/epsilon (stator/rotor) interaction that blocks rotation and inhibits catalysis. Furthermore, the rate of beta-epsilon cross-linking is much faster than that indicated by previous studies, allowing for the possibility of a rapid response to regulatory signals. PMID:15199054

Bulygin, Vladimir V; Duncan, Thomas M; Cross, Richard L

2004-08-20

190

Proposal of new structure of MgB 2 wires with low AC loss for stator windings of fully superconducting motors located in iron core slots  

NASA Astrophysics Data System (ADS)

The new structure of MgB 2 monofilamentary wires for stator windings of fully superconducting motors is proposed to reduce their AC losses in iron core slots for the application of an alternating transport current. In order to validate the proposed structure of wire for loss reduction, numerical calculations are carried out by means of a finite element method using edge elements formulated with a self-field due to currents induced in an analysis region. It is assumed that the voltage-current characteristics of the MgB 2 superconductor are given by Bean’s critical state model, in which the critical current density is independent of the local magnetic field. The influences of wire structures on the AC losses are discussed quantitatively toward the optimum design of stator windings in fully superconducting motors with the MgB 2 wires.

Kajikawa, K.; Osaka, R.; Kuga, H.; Nakamura, T.; Wakuda, T.

2011-11-01

191

Single-stage experimental evaluation of tandem-airfoil rotor and stator blading for compressors. Part 3: Data and performance for stage C  

NASA Technical Reports Server (NTRS)

Stage C, comprised of tandem-airfoil rotor C and tandem-airfoil stator B, was designed and tested to establish performance data for comparison with the performance of conventional single-airfoil blading. Velocity diagrams and blade leading and trailing edge metal angles selected for the conventional rotor and stator blading were used in the design of the tandem blading. The rotor had an inlet hub/tip ratio of 0.8 and a design tip velocity of 757 ft/sec. At design equivalent rotor speed, rotor C achieved a maximum adiabatic efficiency of 91.8% at a pressure ratio of 1.31. The stage maximum adiabatic efficiency was 86.5% at a pressure ratio of 1.31.

Brent, J. A.; Clemmons, D.

1972-01-01

192

Investigation of Turbines Suitable for Use in a Turbojet Engine Wtih High Compressor Pressure Ratio and Low Compressor-tip Speed V : Experimental Performance of Two-stage Turbine with Downstream Stator  

NASA Technical Reports Server (NTRS)

An experimental investigation of a highly loaded two-stage turbine with a downstream stator revealed that (1) at equivalent design work and speed the brake internal efficiency was 0.81 and the maximum efficiency obtained was 0.85, and (2) the downstream stator left very little energy in the form of tangential velocity in the gas and, in general, performed well with 0.78 recovery being obtained at equivalent design work and speed.

Davison, Elmer H; Petrash, Donald A; Schum, Harold J

1951-01-01

193

Cold-air performance of a 15. 41-cm-tip-diameter axial-flow power turbine with variable-area stator designed for a 75kW automotive gas-turbine engine  

Microsoft Academic Search

Experimentally determined performance data are presented for the power turbine stage of the Department of Energy upgraded automotive gas turbine engine. The power turbine is a single-stage, axial-flow design with pivotable vanes to vary stator area for engine control and braking. The stage performance evaluation was performed with dry air at nominal stator inlet conditions of 320°K and 0.409 atmosphere.

K. L. McLallin; M. G. Kofskey; R. Y. Wong

1982-01-01

194

An Improved Model for the Back-EMF and Cogging Torque Characteristics of a Novel Axial Flux Permanent Magnet Synchronous Machine With a Segmental Laminated Stator  

Microsoft Academic Search

An improved model for the back-electromagnetic-force (back-EMF) and cogging torque characteristics of a novel axial flux permanent magnet (AFPM) synchronous machine with a segmental laminated stator is presented. Based on a 3-D finite-element analysis (FEA) modeling approach that takes into the anisotropic properties of the machine's laminated cores, the proposed model provides superior performance prediction to existing isotropic models, in

W. Fei; P. C. K. Luk

2009-01-01

195

Detection of the Short-Circuit Faults in the Stator Winding of Induction Motors based on Harmonics of the Neighboring Magnetic Field  

NASA Astrophysics Data System (ADS)

Based on the time domain finite element analysis of the electromagnetic field, this paper studies the signature of the short-circuit faults inside the stator winding in the magnetic field outside induction motors. The detection of the such a fault is based on the evaluation of the output voltage of coil sensors placed in the motors neighbouring and the comparison of amplitudes of harmonics of this voltage for the healthy and faulty operation states.

Fireteanu, V.

2013-06-01

196

High-loading low-speed fan study. 4: Data and performance with redesign stator and including a rotor tip casing treatment  

NASA Technical Reports Server (NTRS)

A single stage fan with a rotor tip speed of 1000 ft/sec(304.8 m/sec) and a hub-to-tip ratio of 0.392 was retested with a redesigned stator. Tests were conducted with uniform inlet, tip-radial, hub-radial, and circumferential inlet distortions. With uniform inlet flow, stall margin was improved 12 percentage points above that with the original stator. The fan demonstrated an efficiency of 0.883 and a stall margin of 15 percent at a pressure ratio of 1.488 and a specific flow of 41.17 lb/sec/sq ft. Tests were also made with a redesigned casing treatment consisting of skewed slots over the rotor blade tips. This casing treatment gave a 7 percentage point improvement in stall margin when tested with tip radial distortion (when the rotor tip initiated stall). Noise measurements at the fan inlet and exit indicate no effect from closing the stator 10 degrees, nor were there measurable effects from adding skewed slots over the blade tips.

Harley, K. G.; Odegard, P. A.; Burdsall, E. A.

1972-01-01

197

Exploring the possibilities to control the molecular switching properties and dynamics: A field-switchable rotor-stator molecular system  

NASA Astrophysics Data System (ADS)

A bistable, dipolar stator-rotor molecular system-candidate for molecular electronics is investigated. We demonstrate that it is possible to control the intramolecular torsional states and dynamics in this system by applying an appropriate additional electric field (instead of biasing one), achieving fine tuning and modulation of the relevant properties. The electric field effects on the quantities responsible for torsional dynamics (potential energy surface, potential barrier height, quantum and classical transition probabilities, correlation time, HOMO-LUMO gap) are studied from first principles. Our results indicate that it is possible to artificially stabilize the metastable conformational state of the studied molecule. The importance of this is evident, as the current-voltage characteristics of the metastable state are clearly distinguishable from the current-voltage characteristics of the two stable states. We report for the first time exact calculations related to the possibilities to control the thermally induced stochastic switching, and reduce the noise in a practical application. Thus, we believe that the molecule studied in this paper could operate as a field-switchable molecular device under real conditions.

Petreska, Irina; Pejov, Ljup?o; Kocarev, Ljup?o

2011-01-01

198

Prédiction des vibrations du stator d'une machine à réluctance variable en fonction du courant absorbé  

NASA Astrophysics Data System (ADS)

In order to predict the radial vibration of the stator core of a Doubly Salient Switched Reluctance Motor (D.S.S.R.M.), different causes of vibrations are considered. In this kind of machine, electromagnetic stress is found to be the most significant cause of vibrations. The local magnetic stress distribution, depending on magnetic field and finally on the phase current, is calculated in the case of an unsatured operation. This magnetic stress acts in two ways: a tangential force (torque) and a radial attractive force. This radial force excites the vibration modes of the stator, this vibration behaviour is measured in the aligned position and is identified as a transfert function. Finally several experiments show the good accuracy of this simple model. This model will be later used to study the effect of phase current and of static converter on vibration and acoustic noise emitted by the D.S.S.R.M. L'étude du bruit et des vibrations dans le matériel électrique fait intervenir plusieurs systèmes physiques couplés. Le modèle complet est complexe et ne permet pas d'études paramétriques simples de la structure de la machine, de son alimentation et cela pour différents points de fonctionnement. Dans cet article est présenté un modèle simple permettant de prédire l'accélération radiale d'un Moteur à Réluctance Variable à Double Saillance (M.R.V.D.S.) en fonction du courant d'alimentation. Ce modèle permettra d'étudier ultérieurement l'influence de l'alimentation sur le comportement vibratoire de la machine. En premier lieu, les différentes sources de vibrations d'une machine tournante sont évoquées, pour finalement ne s'intéresser qu'aux efforts d'origine magnétique qui sont prépondérants dans les M.R.V.D.S. Le calcul de ces efforts en fonction du courant est présenté dans le cas d'une machine fonctionnant en régime linéaire (sans saturation magnétique). Ces efforts sont décomposés en une force tangentielle créant le couple de rotation et une force radiale ne créant aucun couple. Les formulations sont appliquées à une M.R.V.D.S. de type 6/4 d'une puissance de 30 W. Une identification expérimentale du comportement vibratoire de la machine à rotor bloqué et en monophasé permet de connaître la réponse de la structure à ces efforts magnétiques. Cette réponse mécanique est identifiée à une fonction de transfert. Le modèle complet prend en compte l'alimentation de la machine, la relation entre le courant d'ajimentation et les efforts ainsi que la réponse vibratoire de la machine à ces efforts. Enfin des résultats expérimentaux originaux permettent de valider le modèle dans le cadre des hypothèses définies.

Camus, F.; Gabsi, M.; Multon, B.

1997-02-01

199

Tribenzotriquinacene receptors for C60 ?fullerene rotors: towards C3 symmetrical chiral stators for unidirectionally operating nanoratchets.  

PubMed

The synthesis of a stereochemically pure concave tribenzotriquinacene receptor (7) for C60 fullerene, possessing C3 point group symmetry, by threefold condensation of C2 -symmetric 1,2-diketone synthons (5) and a hexaaminotribenzotriquinacene core (6) is described. The chiral diketone was synthesized in a five-step reaction sequence starting from C2h -symmetric 2,6-di-tert-butylanthracene. The highly diastereo-discriminating Diels-Alder reaction of 2,6-di-tert-butylanthracene with fumaric acid di(-)menthyl ester, catalyzed by aluminium chloride, is the relevant stereochemistry introducing step. The structure of the fullerene receptor was verified by (1)H and (13)C?NMR spectroscopy, mass spectrometry and single crystal X-ray diffraction. VCD and ECD spectra were recorded, which were corroborated by ab initio DFT calculations, establishing the chiral nature of 7 with about 99.7?% ee, based on the ee (99.9?%) of the chiral synthon (1). The absolute configuration of 7 could thus be established as all-S [(2S,7S,16S,21S,30S,35S)-(7)]. Spectroscopic titration experiments reveal that the host forms 1:1 complexes with either pure fullerene (C60) or fullerene derivatives, such as rotor 1'-(4-nitrophenyl)-3'-(4-N,N-dimethylaminophenyl)-pyrazolino[4',5':1,2][60]fullerene (R). The complex stability constants of the complexes dissolved in CHCl3/CS2 (1:1 vol.?%) are K([C60 ?7]) = 319(±156)?M(-1) and K([R?7]) = 110(±50)?M(-1). With molecular dynamics simulations using a first-principles parameterized force field the asymmetry of the rotational potential for [R?7] was shown, demonstrating the potential suitability of receptor 7 to act as a stator in a unidirectionally operating nanoratchet. PMID:24965605

Bredenkötter, Björn; Grzywa, Maciej; Alaghemandi, Mohammad; Schmid, Rochus; Herrebout, Wouter; Bultinck, Patrick; Volkmer, Dirk

2014-07-14

200

Single-stage experimental evaluation of tandem-airfoil rotor and stator blading for compressors. Part 2: Data and performance for stage A  

NASA Technical Reports Server (NTRS)

Stage A, comprised of a conventional rotor and stator, was designed and tested to establish a performance baseline for comparison with the results of subsequent tests planned for two tandem-blade stages. The rotor had an inlet hub/tip ratio of 0.8 and a design tip velocity of 757 ft/sec. At design equivalent rotor speed, rotor A achieved a maximum adiabatic efficiency of 85.1 percent at a pressure ratio of 1.29. The stage maximum adiabatic efficiency was 78.6 percent at a pressure ratio of 1.27.

Brent, J. A.

1972-01-01

201

Single-stage evaluation of highly-loaded high-Mach-number compressor stages 5. Data and performance of baseline, corner-blow wall suction and combined corner blow wall suction stator  

NASA Technical Reports Server (NTRS)

A single-stage compressor with a rotor tip speed of 1600 ft/sec and a 0.5 hub tip ratio was used to investigate the effects of several stator endwall treatment methods on stage range and performance. These endwall treatment methods consisted of stator corner-blow, annular wall suction upstream of stator leading edge, and combined corner-blow and annular wall suction. The overall stage performance with corner blow was essentially the same as the baseline performance. The performance for the annular wall suction and the combined corner-blow and wall suction showed a reduction in peak efficiency of 2.5 percentage points compared to the baseline data.

Nikkanen, J. P.; Brooky, J. P.

1972-01-01

202

Variable stator radial turbine  

NASA Technical Reports Server (NTRS)

A radial turbine stage with a variable area nozzle was investigated. A high work capacity turbine design with a known high performance base was modified to accept a fixed vane stagger angle moveable sidewall nozzle. The nozzle area was varied by moving the forward and rearward sidewalls. Diffusing and accelerating rotor inlet ramps were evaluated in combinations with hub and shroud rotor exit rings. Performance of contoured sidewalls and the location of the sidewall split line with respect to the rotor inlet was compared to the baseline. Performance and rotor exit survey data are presented for 31 different geometries. Detail survey data at the nozzle exit are given in contour plot format for five configurations. A data base is provided for a variable geometry concept that is a viable alternative to the more common pivoted vane variable geometry radial turbine.

Rogo, C.; Hajek, T.; Chen, A. G.

1984-01-01

203

Effects of inlet turbulence and rotor/stator interactions on the aerodynamics and heat transfer of a large-scale rotating turbine model. Part 4: Aerodynamic data tabulation  

SciTech Connect

A combined experimental and analytical program was conducted to examine the effects of inlet turbulence and airfoil heat transfer. The experimental portion of the study was conducted in a large-scale (approx. 5X engine), ambient temperature, rotating turbine model configured in both single-stage and stage-and-a-half arrangements. Heat transfer measurements were obtained using low-conductivity air foils with miniature thermocouples welded to a thin, electrically heated surface skin. Heat transfer data were acquired for various combinations of low or high inlet turbulence intensity, flow coefficient, first stator-rotor axial spacing, Reynolds number and relative circumferential position of the first and second stators. Aerodynamic measurements obtained include distributions of the mean and fluctuating velocities at the turbine inlet and, for each airfoil row, midspan airfoil surface pressures and circumferential distributions of the downstream steady state pressures and fluctuating velocities. Results include airfoil heat transfer predictions produced using existing 2-D boundary layer computation schemes and an examination of solutions of the unsteady boundary layer equations.

Dring, R.P.; Joslyn, H.D.; Blair, M.F.

1987-11-01

204

Contribution of Many Charged Residues at the Stator-Rotor Interface of the Na+-Driven Flagellar Motor to Torque Generation in Vibrio alginolyticus  

PubMed Central

In torque generation by the bacterial flagellar motor, it has been suggested that electrostatic interactions between charged residues of MotA and FliG at the rotor-stator interface are important. However, the actual role(s) of those charged residues has not yet been clarified. In this study, we systematically made mutants of Vibrio alginolyticus whose charged residues of PomA (MotA homologue) and FliG were replaced by uncharged or charge-reversed residues and characterized the motilities of those mutants. We found that the members of a group of charged residues, 7 in PomA and 6 in FliG, collectively participate in torque generation of the Na+-driven flagellar motor in Vibrio. An additional specific interaction between PomA-E97 and FliG-K284 is critical for proper performance of the Vibrio motor. Our results also reveal that more charged residues are involved in the PomA-FliG interactions in the Vibrio Na+-driven motor than in the MotA-FliG interactions in the H+-driven one. This suggests that a larger number of conserved charged residues at the PomA-FliG interface contributes to the robustness of the Vibrio motor against mutations. The interaction surfaces of the stator and rotor of the Na+-driven motor seem to be more complex than those previously proposed in the H+-driven motor. PMID:24464458

Takekawa, Norihiro; Kojima, Seiji

2014-01-01

205

Component Performance Investigation of J71 Experimental Turbine. Part 2; Internal-Flow Conditions with 97-Percent-Design Stator Areas  

NASA Technical Reports Server (NTRS)

An experimental investigation of the internal-flow conditions of a J71 experimental turbine equipped with 97-percent-design stator areas was conducted at equivalent design speed and near equivalent design work. The results of the investigation indicate that the stage work distribution closely approximates design, the actual distribution being 44.1, 33.4, and 22.5 percent for the first, second, and third stages, respectively. The first-, second-, and third-stage efficiencies were 0.894, 0.858, and 0.792, respectively. The first and second stages exhibited loss regions near the hub and tip at the rotor blade outlets. The hub loss region is attributed to stator secondary flows, and a contributing factor to the tip loss region may be the high design diffusion on the rotor blade suction surface near the tip. The loss in the third stage is appreciably greater than that in the first or second stage. The fact that the third rotor is unshrouded and has a nominal tip clearance of 0.120 inch may contribute to the higher loss in the tip region of the third stage.

Rebeske, John J., Jr.; Petrash, Donald A.

1956-01-01

206

Blade row dynamic digital compression program. Volume 2: J85 circumferential distortion redistribution model, effect of Stator characteristics, and stage characteristics sensitivity study  

NASA Technical Reports Server (NTRS)

The results of dynamic digital blade row compressor model studies of a J85-13 engine are reported. The initial portion of the study was concerned with the calculation of the circumferential redistribution effects in the blade-free volumes forward and aft of the compression component. Although blade-free redistribution effects were estimated, no significant improvement over the parallel-compressor type solution in the prediction of total-pressure inlet distortion stability limit was obtained for the J85-13 engine. Further analysis was directed to identifying the rotor dynamic response to spatial circumferential distortions. Inclusion of the rotor dynamic response led to a considerable gain in the ability of the model to match the test data. The impact of variable stator loss on the prediction of the stability limit was evaluated. An assessment of measurement error on the derivation of the stage characteristics and predicted stability limit of the compressor was also performed.

Tesch, W. A.; Steenken, W. G.

1978-01-01

207

Subunit Positioning and Stator Filament Stiffness in Regulation and Power Transmission in the V1 Motor of the Manduca sexta V-ATPase?  

PubMed Central

The vacuolar H+-ATPase (V-ATPase) is an ATP-driven proton pump essential to the function of eukaryotic cells. Its cytoplasmic V1 domain is an ATPase, normally coupled to membrane-bound proton pump Vo via a rotary mechanism. How these asymmetric motors are coupled remains poorly understood. Low energy status can trigger release of V1 from the membrane and curtail ATP hydrolysis. To investigate the molecular basis for these processes, we have carried out cryo-electron microscopy three-dimensional reconstruction of deactivated V1 from Manduca sexta. In the resulting model, three peripheral stalks that are parts of the mechanical stator of the V-ATPase are clearly resolved as unsupported filaments in the same conformations as in the holoenzyme. They are likely therefore to have inherent stiffness consistent with a role as flexible rods in buffering elastic power transmission between the domains of the V-ATPase. Inactivated V1 adopted a homogeneous resting state with one open active site adjacent to the stator filament normally linked to the H subunit. Although present at 1:1 stoichiometry with V1, both recombinant subunit C reconstituted with V1 and its endogenous subunit H were poorly resolved in three-dimensional reconstructions, suggesting structural heterogeneity in the region at the base of V1 that could indicate positional variability. If the position of H can vary, existing mechanistic models of deactivation in which it binds to and locks the axle of the V-ATPase rotary motor would need to be re-evaluated. PMID:24075871

Muench, Stephen P.; Scheres, Sjors H.W.; Huss, Markus; Phillips, Clair; Vitavska, Olga; Wieczorek, Helmut; Trinick, John; Harrison, Michael A.

2014-01-01

208

Measurements of the unsteady flow field within the stator row of a transonic axial-flow fan. 1: Measurement and analysis technique  

NASA Technical Reports Server (NTRS)

This two-part paper presents laser anemometer measurements of the unsteady velocity field within the stator row of a transonic axial-flow fan. The objective is to provide additional insight into unsteady blade-row interactions within high speed compressors which affect stage efficiency, energy transfer, and other design considerations. Part 1 describes the measurement and analysis techniques used for resolving the unsteady flow field features. The ensemble-average and variance of the measured velocities are used to identify the rotor wake generated and unresolved unsteadiness, respectively. (Rotor wake generated unsteadiness refers to the unsteadiness generated by the rotor wake velocity deficit and the term unresolved unsteadiness refers to all remaining contributions to unsteadiness such as vortex shedding, turbulence, mass flow fluctuations, etc.). A procedure for calculating auto and cross correlations of the rotor wake generated and unresolved unsteady velocity fluctuations is described. These unsteady-velocity correlations have significance since they also result from a decomposition of the Navier-Stokes equations. This decomposition of the Navier-Stokes equations resulting in the velocity correlations used to describe the unsteady velocity field will also be outlined in this paper.

Suder, K. L.; Hathaway, M. D.; Okiishi, T. H.; Strazisar, A. J.; Adamczyk, J. J.

1987-01-01

209

Surface Temperature Measurements from a Stator Vane Doublet in a Turbine Engine Afterburner Flame using Ultra-Bright Cr-Doped GdAlO3 Thermographic Phosphor  

NASA Technical Reports Server (NTRS)

Luminescence-based surface temperature measurements from an ultra-bright Cr-doped GdAlO3 perovskite (GAP:Cr) coating were successfully conducted on an air-film-cooled stator vane doublet exposed to the afterburner flame of a J85 test engine at University of Tennessee Space Institute (UTSI). The objective of the testing at UTSI was to demonstrate that reliable thermal barrier coating (TBC) surface temperatures based on luminescence decay of a thermographic phosphor could be obtained from the surface of an actual engine component in an aggressive afterburner flame environment and to address the challenges of a highly radiant background and high velocity gases. A high-pressure turbine vane doublet from a Honeywell TECH7000 turbine engine was coated with a standard electron-beam physical vapor deposited (EB-PVD) 200-m-thick TBC composed of yttria-stabilized zirconia (YSZ) onto which a 25-m-thick GAP:Cr thermographic phosphor layer was deposited by EB-PVD. The ultra-bright broadband luminescence from the GAP:Cr thermographic phosphor is shown to offer the advantage of over an order-of-magnitude greater emission intensity compared to rare-earth-doped phosphors in the engine test environment. This higher emission intensity was shown to be very desirable for overcoming the necessarily restricted probe light collection solid angle and for achieving high signal-to-background levels. Luminescence-decay-based surface temperature measurements varied from 500 to over 1000C depending on engine operating conditions and level of air film cooling.

Eldridge, Jeffrey I.; Jenkins, Thomas P.; Allison, Stephen W.; Wolfe, Douglas E.; Howard, Robert P.

2013-01-01

210

Stator and multiple piece seal  

Microsoft Academic Search

A gas turbine engine is described comprising a compressor section, a combustor section and a turbine section arranged in flow series and defining an annular flow path extending axially from the compressor section through the turbine section, the engine further comprising a plurality of air passageways extending from the compressor section to a plenum in the turbine section so that

M. A. Heldreth; S. R. Buckert

1993-01-01

211

The effects of inlet turbulence and rotor/stator interactions on the aerodynamics and heat transfer of a large-scale rotating turbine model. Part 4: Aerodynamic data tabulation  

NASA Technical Reports Server (NTRS)

A combined experimental and analytical program was conducted to examine the effects of inlet turbulence and airfoil heat transfer. The experimental portion of the study was conducted in a large-scale (approx. 5X engine), ambient temperature, rotating turbine model configured in both single-stage and stage-and-a-half arrangements. Heat transfer measurements were obtained using low-conductivity airfoils with miniature thermocouples welded to a thin, electrically heated surface skin. Heat transfer data were acquired for various combinations of low or high inlet turbulence intensity, flow coefficient, first stator-rotor axial spacing, Reynolds number and relative circumferential position of the first and second stators. Aerodynamic measurements obtained include distributions of the mean and fluctuating velocities at the turbine inlet and, for each airfoil row, midspan airfoil surface pressures and circumferential distributions of the downstream steady state pressures and fluctuating velocities. Results include airfoil heat transfer predictions produced using existing 2-D boundary layer computation schemes and an examination of solutions of the unsteady boundary layer equations.

Dring, R. P.; Joslyn, H. D.; Blair, M. F.

1987-01-01

212

Assembly of the stator in Escherichia coli ATP synthase. Complexation of alpha subunit with other F1 subunits is prerequisite for delta subunit binding to the N-terminal region of alpha  

PubMed Central

Alpha subunit of Escherichia coli ATP synthase was expressed with a C-terminal 6-His tag and purified. Pure alpha was monomeric, competent in nucleotide binding, and had normal N-terminal sequence. In F1-subunit dissociation/reassociation experiments it supported full reconstitution of ATPase, and reassociated complexes were able to bind to F1-depleted membranes with restoration of ATP-driven proton pumping. Therefore interaction between the stator delta subunit and the N-terminal residue 1-22 region of alpha occurred normally when pure alpha was complexed with other F1 subunits. On the other hand, three different types of experiment showed that no interaction occurred between pure delta and isolated alpha subunit. Unlike in F1, the N-terminal region of isolated alpha was not susceptible to trypsin cleavage. Therefore, during assembly of ATP synthase, complexation of alpha subunit with other F1 subunits is prerequisite for delta subunit binding to the N-terminal region of alpha. We suggest that the N-terminal 1-22 residues of alpha are sequestered in isolated alpha until released by binding of beta to alpha subunit. This prevents 1/1 delta/alpha complexes from forming, and provides a satisfactory explanation of the stoichiometry of one delta per three alpha seen in the F1 sector of ATP synthase, assuming that steric hindrance prevents binding of more than one delta to the alpha3/beta3 hexagon. The cytoplasmic fragment of the b subunit (bsol) did not bind to isolated alpha. It might also be that complexation of alpha with beta subunits is prerequisite for direct binding of stator b subunit to the F1-sector. PMID:17176112

Senior, Alan E.; Muharemagi, Alma; Wilke-Mounts, Susan

2008-01-01

213

Atlas del Genoma del Cáncer  

Cancer.gov

Es posible que haya más de 200 tipos diferentes de cáncer y muchos subtipos más, cada uno de estos causado por errores en el ADN que desencadenan el crecimiento descontrolado de las células. La identificación de los cambios en el conjunto completo de ADN de cada tipo de cáncer, su genoma, y el entendimiento de cómo interactúan dichos cambios para impulsar el proceso de la enfermedad sentarán las bases de una era individualizada de tratamiento del cáncer.

214

Instantánea del cáncer colorrectal  

Cancer.gov

Información sobre las tendencias de incidencia, mortalidad y financiamiento del NCI sobre el cáncer colorrectal; así como ejemplos de actividades del NCI y adelantos en la investigación de este tipo de cáncer.

215

Ceramic turbine stator vane and shroud support  

DOEpatents

A support system for supporting the stationary ceramic vanes and ceramic outer shrouds which define the motive fluid gas path in a gas turbine engine is shown. Each individual segment of the ceramic component whether a vane or shroud segment has an integral radially outwardly projecting stem portion. The stem is enclosed in a split collet member of a high-temperature alloy material having a cavity configured to interlock with the stem portion. The generally cylindrical external surface of the collet engages a mating internal cylindrical surface of an aperture through a supporting arcuate ring segment with mating camming surfaces on the two facing cylindrical surfaces such that radially outward movement of the collet relative to the ring causes the internal cavity of the collet to be reduced in diameter to tightly engage the ceramic stem disposed therein. A portion of the collet extends outwardly through the ring segment opposite the ceramic piece and is threaded for receiving a nut and a compression washer for retaining the collet in the ring segment under a continuous biasing force urging the collet radially outwardly.

Glenn, Robert G. (Lower Moreland Township, Montgomery County, PA)

1981-01-01

216

Rotor-Stator-Kontakt polygonfrmigen Fanglagern  

E-print Network

PVC-Hülse: Exponent (Normalkraft): Steifigkeitsfaktor: Verlustbeiwert: Reibzahl (Maximalwert): 19,0 s: Periodische Bewegungen Laval-Rotor: Drehfrequenz f = 6 Hz Fanglager: starre Aufhängung, PVC-Hülse #12 Aufhängung, PVC-Hülse 3 4 6 8 12 18 24 36 72 rund Anzahl der Fangflächen m 0 0.2 0.4 0.6 0.8 1 1.2 1.4 1

Pfeifer, Holger

217

Temas y rumbos del teatro rural hispanoamericano del siglo XX.  

E-print Network

de peculiaridades fonéticas. Son pocos, en realidad, los autores de dramas campesinos que no se han servido del pintoresco lenguaje del campo.1 Algunos autores utilizan fábulas del acervo folklórico para montar piezas de teatro con el fin de...

Neglia, Erminio G.

1971-10-01

218

Boletín del Instituto Nacional del Cáncer - 07-20-2010  

Cancer.gov

El doctor Harold Varmus, acompañado de su esposa Constance Casey (centro), presta juramento como director del NCI ante la Secretaria del Departamento de Salud y Servicios Humanos, Kathleen Sebelius, el lunes 12 de julio. (Foto cortesía de Chris Smith) El 12 de julio, el doctor Harold Varmus prestó juramento ante la Secretaria del Departamento de Salud y Servicios Humanos de los Estados Unidos, Kathleen Sebelios, como el decimocuarto director del Instituto Nacional del Cáncer.

219

El pronóstico del cáncer  

Cancer.gov

Hoja informativa sobre la predicción de resultados y recuperación de una enfermedad, y sobre cómo las estadísticas ayudan a los médicos a hacer una estimación del pronóstico de un paciente con cáncer.

220

Espectroscopia del Cometa Halley  

NASA Astrophysics Data System (ADS)

Se reportan observaciones espectroscópicas del cometa Halley. Los espectros fueron tomados usando el espectrógrafo del telescopio reflector de 1 metro del Observatorio Nacional de Venezuela. Se utilizó óptica azul, con una red de difracción de 600 lineas/min, obteniéndose una dispersión de 74.2 A/mm y una resolución de 2.5 A, en el rango espectral de 3500 a 6500 A. Seis placas fueron tomadas con emulsión IIa-O y dos con IIa-D. Los tiempos de exposición fueron entre 10 y 150 minutos. El cometa se encontraba entre 0.70 y 1.04 UA del Sol, y entre 1.28 y 0.73 UA de la Tierra. Las emisiones más prominentes en el espectro, son las del CN, C2, y C3. Otras emisiones detectadas corresponden a CH, NH2 y Na. Los espectros muestran un fuerte continuo, indicando un contenido significativo de polvo. Se detectó mayor intensidad del contínuo, en la dirección anti solar, lo cual es evidencia de la cola de polvo.

Naranjo, O.; Fuenmayor, F.; Ferrin, L.; Bulka, P.; Mendoza, C.

1987-05-01

221

Control del cáncer y salud mundial: noticia del Instituto Nacional del Cáncer (NCI)  

Cancer.gov

En combinación con una reunión de alto nivel de las Naciones Unidas sobre enfermedades no transmisibles en países en vías de desarrollo, el doctor Harold Varmus, director del NCI, y el doctor Ted L. Trimble, del NCI, han publicado un comentario en Science Translational Medicine sobre “La integración del control del cáncer en la salud mundial" (Integrating Cancer Control into Global Health).

222

Boletín del Instituto Nacional del Cáncer  

Cancer.gov

No se puede negar que vivimos en una comunidad global, en la que los eventos de una ciudad o país pueden tener graves consecuencias para los residentes de otra ciudad o país a miles de kilómetros de distancia. Ya sea la pandemia del virus H1N1, los recientes disturbios en Irán o la recesión económica mundial, es evidente que esta interconectividad trae consigo retos importantes. Pero también puede crear oportunidades sin precedentes, en particular aquellas que podrían mejorar sustancialmente la salud pública.

223

ENCUESTA A NEUMONOLOGOS SOBRE EL DIAGNOSTICO Y TRATAMIENTO DE EPOC  

Microsoft Academic Search

Survey of chest physicians regarding COPD diagnosis and treatment. A survey on COPD diag- nostic procedures, treatment and management was conducted in a group of 517 chest physicians randomized from a list of the 1121 affiliates to the Asociación Argentina de Medicina Respiratoria. One hundred eighty- seven responses were obtained (36.2% of the questionnaires mailed). They treat an average of

MARTIN L. SIVORI; GUILLERMO A. RAIMONDI

224

Museo Universitario del Chopo Datos del plan de estudio  

E-print Network

and roll 4. Mambo 5. Merengue 6. Disco 7. Cumbia 8. Cha cha cha 9. Salsa en Línea 10. Hip Hop 11. CancionesMuseo Universitario del Chopo Datos del plan de estudio Nombre del Taller: Dancing en México

Islas, León

225

Pruebas de Papanicolaou y del virus del papiloma humano (VPH)  

Cancer.gov

Hoja informativa que describe los exámenes selectivos de detección del cáncer de cérvix, los cuales incluyen la prueba de Papanicolaou y la prueba de los virus del papiloma humano. La hoja informativa incluye también información acerca de las pautas de exámenes de detección del cáncer de cérvix.

226

Boletín del Instituto Nacional del Cáncer - 08-17-2010  

Cancer.gov

En la reunión del 20 de julio, los miembros del comité revisaron los resultados finales de esos estudios, en los cuales no se pudo confirmar la información que llevó a la aprobación acelerada. Las mujeres del estudio inicial, llamado E2100, recibieron paclitaxel (Taxol) solo o paclitaxel más bevacizumab para tratar el cáncer de mama localizado recidivante.

227

Instantánea del cáncer de pulmón  

Cancer.gov

Información sobre las tendencias de incidencia, mortalidad y financiamiento del NCI sobre el cáncer de pulmón; así como ejemplos de actividades del NCI y adelantos en la investigación de este tipo de cáncer.

228

Instantánea del cáncer de riñón  

Cancer.gov

Información sobre las tendencias de incidencia, mortalidad y financiamiento del NCI sobre el cáncer de riñón; así como ejemplos de actividades del NCI y adelantos en la investigación de este tipo de cáncer.

229

Instantánea del cáncer de tiroides  

Cancer.gov

Información sobre las tendencias de incidencia, mortalidad y financiamiento del NCI sobre el cáncer de tiroides; así como ejemplos de actividades del NCI y adelantos en la investigación de este tipo de cáncer.

230

Instantánea del cáncer de páncreas  

Cancer.gov

Información sobre las tendencias de incidencia, mortalidad y financiamiento del NCI sobre el cáncer de páncreas; así como ejemplos de actividades del NCI y adelantos en la investigación de este tipo de cáncer.

231

Instantánea del cáncer de ovario  

Cancer.gov

Información sobre las tendencias de incidencia, mortalidad y financiamiento del NCI sobre el cáncer de ovario; así como ejemplos de actividades del NCI y adelantos en la investigación de este tipo de cáncer.

232

Instantánea del cáncer de endometrio  

Cancer.gov

Información sobre las tendencias de incidencia, mortalidad y financiamiento del NCI sobre el cáncer de endometrio; así como ejemplos de actividades del NCI y adelantos en la investigación de este tipo de cáncer.

233

Instantánea del cáncer de próstata  

Cancer.gov

Información sobre las tendencias de incidencia, mortalidad y financiamiento del NCI sobre el cáncer de próstata; así como ejemplos de actividades del NCI y adelantos en la investigación de este tipo de cáncer.

234

Instantánea del cáncer de esófago  

Cancer.gov

Información sobre las tendencias de incidencia, mortalidad y financiamiento del NCI sobre el cáncer de esófago; así como ejemplos de actividades del NCI y adelantos en la investigación de este tipo de cáncer.

235

Instantánea del cáncer de vejiga  

Cancer.gov

Información sobre las tendencias de incidencia, mortalidad y financiamiento del NCI sobre el cáncer de vejiga; así como ejemplos de actividades del NCI y adelantos en la investigación de este tipo de cáncer.

236

Fisiología del crecimiento  

Microsoft Academic Search

ExtractoEl crecimiento humano es un proceso dinámico y complejo que comienza con la fertilización del óvulo y se completa con la fusión de las epífisis y las metáfisis de los huesos largos, que caracteriza la terminación de la adolescencia. El crecimiento ocurre en fases, con características distintivas en términos de influencias dominantes derivadas de factores y patrones genéticos, ambientales\\/nutricionales y

Arlan L. Rosenbloom

2007-01-01

237

-DERECHO PBLICO DEL ESTADO AUTONMICO La implantacin del Mster universitario en Derecho Pblico del Estado Autonmico  

E-print Network

- DERECHO P�BLICO DEL ESTADO AUTON�MICO La implantación del Máster universitario en Derecho Público del Estado Autonómico extinguirá el Máster Oficial en Derecho Autonómico y Local. Por esta razón se materias del Máster Oficial en Derecho Autonómico y Local. Los estudiantes que comenzaron el Máster Oficial

Rey Juan Carlos, Universidad

238

Museo Universitario del Chopo Datos del plan de estudio  

E-print Network

separación de la agrupación musical más importante del Siglo XX, a nuestros días, The Beatles Imparte NACIONAL AUT�NOMA DE M�XICO #12;Revisar la historia de la banda de rock los Beatles, a través del análisis paralelos en el tiempo del cuarteto Liverpool. CONTENIDO 1. La historia des los Beatles, desde sus inicios

Islas, León

239

MÉXICO: DESIGUALDAD SOCIAL Y POBREZA Saldos del “gobierno del empleo”  

Microsoft Academic Search

El gobierno de Felipe Calderón Hinojosa, carente de oficio y de sentido común, no solamente es el gobierno del desempleo sino que también es el gobierno del aumento de las desigualdades sociales y, por tanto, de la pobreza. Y cómo no debería serlo, sí se trata de un gobierno conservador que les quita a los pobres para darles a los

Martín Carlos Ramales Osorio

2010-01-01

240

Boletín del Instituto Nacional del Cáncer - 09-14-2010  

Cancer.gov

Las mediciones ecocardiográficas del ventrículo izquierdo del corazón sirven para que los médicos monitoreen el funcionamiento cardiaco durante el tratamiento contra el cáncer. Una reducción de la fracción de eyección ventricular izquierda (LVEF) durante el tratamiento puede indicar daño cardiaco provocado por los fármacos. Haga clic para ampliar.

241

El valor del consejo en el Libro del caballero Zifar Patricia ROCHWERT-ZUILI  

E-print Network

1 El valor del consejo en el Libro del caballero Zifar Patricia ROCHWERT-ZUILI Textes et cultures Libro del caballero Zifar la definición del consejo como elemento fundamental del molinismo. El análisis la realeza. Palabras clave: Consejo, palabra, amistad, verdad, seso, entendimiento, Libro del

Paris-Sud XI, Université de

242

EL ORIGEN BIOLÓGICO DEL DERECHO  

Microsoft Academic Search

En este trabajo se aborda el posible origen evolutivo del derecho como una consecuencia del desarrollo social de nuestra especie. Otras especies con sistemas sociales similares presentan varias reglas para la convivencia en grupo. Algunas de estas reglas son comunes en todas las especies con comportamiento social. El desarrollo de la sociobiología en las últimas décadas es una herramienta importante

Axel P. Retana-Salazar

243

Teatro uruguayo hacia el fin del siglo  

E-print Network

del Interior y la Asociación General de Autores del Uruguay, y presidida por un representante del Ministerio de Educación y Cultura. 84 LATIN AMERICAN THEATRE REVIEW Pero los magros recursos asignados al Fondo de Teatro por dicha ley, consistentes...

Pignataro Calero, Jorge

1993-10-01

244

Vacunas contra los virus del papiloma humano  

Cancer.gov

Hoja informativa acerca de las vacunas contra los virus del papiloma humano (VPH) para prevenir infecciones con ciertos tipos de VPH, los cuales son la causa principal del cáncer de cuello del útero o cérvix.

245

Siga adelante: la vida después del tratamiento del cáncer  

Cancer.gov

E-book con consejos para supervivientes de cáncer e información sobre temas relacionados con la vida después del tratamiento, entre ellos, la atención médica de seguimiento, los cambios físicos y emocionales y los cambios en el estilo de vida.

246

Boletín del Instituto Nacional del Cáncer - 05-25-2010  

Cancer.gov

Aproximadamente 41.000 participantes en un estudio en el Reino Unido se sometieron una sola vez a una examen de detección en la parte inferior del colon mediante el uso de un sigmoidoscopio, un instrumento delgado en forma de tubo que se inserta a través del recto para buscar lesiones precancerosas o cancerosas. Este dispositivo también tiene una herramienta para extraer pólipos potencialmente precancerosos.

247

Como Solicitar Los Beneficios del Seguro del Desempleo Transcripcin  

E-print Network

depende en los ingresos que ha ganado en un periodo de 12 meses...esto es lo que se le llama ingresos del éste Segundo...usted puede visitar nuestro sitio de Internet y presentar su solicitud en línea O. Busque el enlace de la "Lista de Verificación" en nuestro sitio del Internet. Púlselo e imprímalo. Al

248

Boletín del Instituto Nacional del Cáncer - 3 de enero 2013  

Cancer.gov

En Estados Unidos nos bombardean con información sobre los exámenes de detección del cáncer. Los comerciales radiales tratan de atraer a la gente a los centros médicos subrayando los beneficios de los exámenes de detección del cáncer de pulmón. Algunos grupos de defensa promueven los exámenes para el cáncer de próstata o de mama. Y los medios enfatizan los beneficios de estas pruebas. Pero mucha gente no entiende la complejidad de estos procedimientos.

249

Antioxidantes y prevención del cáncer  

Cancer.gov

Hoja informativa acerca de los antioxidantes, sustancias que pueden proteger las células del daño causado por moléculas inestables conocidas como radicales libres. El daño de los radicales libres puede resultar en cáncer.

250

Case Study: del Amo Bioventing  

EPA Science Inventory

The attached presentation discusses the fundamentals of bioventing in the vadose zone. The basics of bioventing are presented. The experience to date with the del Amo Superfund Site is presented as a case study....

251

Se da a conocer el plan del Instituto Nacional del Cáncer para acelerar la investigación del cáncer  

Cancer.gov

En la 100va Reunión Anual de la Asociación Estadounidense de Investigación del Cáncer realizada en Denver, el director del Instituto Nacional del Cáncer, doctor John E. Niederhuber, dio a conocer detalles importantes, tales como financiamiento de más subvenciones, creación de una plataforma para atención personalizada del cáncer y un programa acelerado de genética del cáncer que hará avanzar la investigación oncológica en este nuevo ambiente económico.

252

Harold Varmus investido bajo juramento como 14.º director del Instituto Nacional del Cáncer  

Cancer.gov

Ganador del Premio Nobel, doctor Harold E. Varmus, prestó juramento hoy como 14.º director del Instituto Nacional del Cáncer (NCI).  "Es muy estimulante que estés de regreso con nosotros", dijo la secretaria del Departamento de Salud y Servicios Humanos Kathleen Sebelius en la ceremonia de toma de juramento. “Hoy se abre un nuevo capítulo para el Instituto Nacional del Cáncer”.

253

VIII Encuentro Nacional de Teatro del CLETA  

E-print Network

popular de las "calaveras," poemitas satíricos que se circulan en México por motivo del día dos de noviembre, "Día de los Muertos," destacaron esa noche las "calaças" originales del Llanero Solitito; por ejemplo, la siguiente a propósito del actual... contribuir al fortalecimiento de organizaciones políticas y sociales que contribuyan a la destrucción del sistema de explotación del hombre por el hombre." Durante los diez días que duró el VIII Encuentro, hubo presentaciones tanto en foros cerrados como...

Frischmann, Donald H.

1983-10-01

254

Boletín del Instituto Nacional del Cáncer - 29 de marzo de 2011  

Cancer.gov

Los artículos originales en inglés se encuentran disponibles en las páginas del NCI Cancer Bulletin. El Boletín es una publicación del Instituto Nacional del Cáncer (NCI), una entidad gubernamental de los Estados Unidos creada en 1937.

255

Boletín del Instituto Nacional del Cáncer - 21 de junio de 2011  

Cancer.gov

Los artículos originales en inglés se encuentran disponibles en las páginas del NCI Cancer Bulletin. El Boletín es una publicación del Instituto Nacional del Cáncer (NCI), una entidad gubernamental de los Estados Unidos creada en 1937.

256

Boletín del Instituto Nacional del Cáncer - 28 de febrero de 2012  

Cancer.gov

Los artículos originales en inglés están disponibles en las páginas del NCI Cancer Bulletin. El Boletín es una publicación del Instituto Nacional del Cáncer (NCI), una entidad gubernamental de los Estados Unidos creada en 1937.

257

en el mundo Trasplante del arroz en Madagascar  

E-print Network

Ciencias y Tecnologías del Agua » con la ayuda del Ministerio de Asuntos Extranjeros. África del Norte y internacional MERGUSIE, dedicado al manejo integral del agua en la cuenca vertiente del Merguellil. De éste han tecnologías del agua » del Nepad Los lazos entre el Instituto y el NEPAD (The New Partnership for Africa

258

Boletín del Instituto Nacional del Cáncer - 04-27-2010  

Cancer.gov

Cada vez es más evidente que los esfuerzos mundiales de salud de mayor éxito dependen no solo del aporte de las mentes más brillantes, sino de la colaboración entre ellas para marcar la diferencia en el escenario global. Este enfoque es el motor impulsor detrás de una asociación excepcional con el NCI, financiada en parte por Susan G.

259

Boletín del Instituto Nacional del Cáncer - 01-05-2010  

Cancer.gov

Al caminar por los pasillos del nuevo centro oncológico integral en la sede de Ciencias Médicas de la Universidad de Puerto Rico (UPR) en San Juan, uno debe mantener los ojos abiertos. La mujer que pasa caminando vigorosamente podría ser la doctora Marcia Roxana Cruz-Correa, y no debe uno perderse la oportunidad de conocerla.

260

EL ROL DEL GNERO DENTRO DEL PROCESO DE APRENDIZAJE COLABORATIVO  

E-print Network

de sexo y la forma en que esto afecta las actividades colaborativas. En el presente trabajo se describen los resultados de un experimento desarrollado con el fin de establecer que la diferencia de sexo]. Varios estudios también han demostrado que las diferencias de sexo en el uso del computador están

Guerrero, Luis

261

modelado y analisis del transporte del herbicida glifosato en una ...  

E-print Network

tools for the study of water and contaminant transport in the unsaturated zone. This paper presents ... Tests were designed to. characterize the ... laboratory and field data. RESUMEN ..... donde t1 2/ es la vida-mitad (half-life) del contaminante. El parámetro t1 2/ .... En Soil Science Society of America Journal, 44, 892-898.

(Tom N. Jagatic)

262

Método de determinación del origen geográfico del polen apícola comercial  

Microsoft Academic Search

Cinco muestras de marcas de polen apícola, que son frecuentes en el comercio regional, han sido estudiadas y su composición po- línica analizada mediante diferentes técnicas con el objetivo de conocer su origen geográfico. Se han usado tres métodos que pueden con- siderarse complementarios: los valores porcentuales del análisis de polen por microscopía óptica, el análisis colorimétrico y el estudio

Pilar de Sá-Otero; Silvia Marcial-Bugarín; Sandra Armesto-Baztán; Emilia Díaz-Losada

2002-01-01

263

Boletín del Instituto Nacional del Cáncer - 12-08-2009  

Cancer.gov

El Instituto Nacional del Cáncer (NCI) recientemente puso a disposición carteles y broches de promoción en español para aumentar la concientización sobre los estudios clínicos. Se pretende que los instrumentos animen la conversación con pacientes de cáncer que pudieran estar interesados en participar en un estudio clínico.

264

Coolable stator assembly for a gas turbine engine  

Microsoft Academic Search

This patent describes a rotary machine of the type having an axially extending annular flow path for working medium gases, an axially extending flow path for cooling air and an array of circumferentially adjacent wall segments bounding the working medium flow path which includes a pair of circumferentially adjacent wall segments having facing sides which are free to move axially,

1987-01-01

265

Stator for a rotating electrical machine having multiple control windings  

DOEpatents

A rotating electric machine is provided which includes multiple independent control windings for compensating for rotor imbalances and for levitating/centering the rotor. The multiple independent control windings are placed at different axial locations along the rotor to oppose forces created by imbalances at different axial locations along the rotor. The multiple control windings can also be used to levitate/center the rotor with a relatively small magnetic field per unit area since the rotor and/or the main power winding provides the bias field.

Shah, Manoj R. (Latham, NY); Lewandowski, Chad R. (Amsterdam, NY)

2001-07-17

266

AXIAL TURBINE BLADE VIBRATIONS INDUCED BY THE STATOR FLOW  

Microsoft Academic Search

The forced excitation of the rotor blades of a single-stage turbine due to rotorstator interaction is calculated with an in-house\\u000a unsteady flow solver and a general purpose finite element code. A scaled configuration is used in order to reduce the amount\\u000a of computational effort. The unsteady flow solution is obtained on three blade-to-blade cuts. The time dependent static pressure\\u000a on

M. B. Schmitz; O. Schäfer; J. Szwedowicz; T. Secall-Wimmel; T. P. Sommer

267

Acoustic modulation effect of rotating stator/rotor interaction noise  

E-print Network

order, B(k) is the number of rotor blades, (k) is the angular velocity of the rotor, (l) is the angular on the rotor blades and on the fixed parts. According to the Ffowcs-Williams and Hawk- ings analogy comes from the periodic forces on the rotor blades and the forces on the other static parts of the fan

Boyer, Edmond

268

Motor bearing damage detection using stator current monitoring  

Microsoft Academic Search

This paper addresses the application of motor current spectral analysis for the detection of rolling-element bearing damage in induction machines. Vibration monitoring of mechanical bearing frequencies is currently used to detect the presence of a fault condition. Since these mechanical vibrations are associated with variations in the physical air gap of the machine, the air gap flux density is modulated

Randy R. Schoen; Thomas G. Habetler; Farrukh Kamran; R. G. Bartfield

1995-01-01

269

Turbine rotor-stator leaf seal and related method  

DOEpatents

A seal assembly for installation between rotating and stationary components of a machine includes a first plurality of leaf spring segments secured to the stationary component in a circumferential array surrounding the rotating component, the leaf spring segments each having a radial mounting portion and a substantially axial sealing portion, the plurality of leaf spring segments shingled in a circumferential direction.

Herron, William Lee (Cincinnati, OH); Butkiewicz, Jeffrey John (Simpsonville, SC)

2003-01-01

270

Evaluation of Steam Turbines Triangular Tooth on Stator Labyrinth Seal  

E-print Network

.4. Association of discharge coefficient with Re at different tooth location (compressible flow, case 11 ). ........................................... 84? Fig. 4.5. Streamlines and axial velocity distribution in four teeth... .......................... 85? Fig. 4.6. Discharge coefficient of the seal with four teeth ...................................... 86? xvi Fig. 4.7. Deviation of Cd values at different tooth position for Re ........................ 87? Fig. 4.8. Association of Cd...

Tanvir, Hossain Ahmed

2012-07-16

271

Stator for Rotating Electrical Machine Having Multiple Controlwindings  

SciTech Connect

A rotating electric machine is provided which includes multiple independent control windings for compensating for rotor imbalances and for levitating/centering the rotor. The multiple independent control windings are placed at different axial locations along the rotor to oppose forces created by imbalances at different axial locations along the rotor. The multiple control windings can also be used to levitate/center the rotor with a relatively small magnetic field per unit area since the rotor and/or the main power winding provides the biasfield.

Shah, Manoj R.; Lewandowski, Chad R.

1999-05-05

272

Instantánea del cáncer de cuello uterino  

Cancer.gov

Información sobre las tendencias de incidencia, mortalidad y financiamiento del NCI sobre el cáncer de cuello uterino; así como ejemplos de actividades del NCI y adelantos en la investigación de este tipo de cáncer.

273

Microflora patógena del queso blanco \\  

Microsoft Academic Search

Resumen: Resumen: Resumen: Resumen: Resumen: El queso telita, es un queso blanco de pasta cocida que se vende sumergido en suero y es elaborado por pequeños productores en queseras artesanales, ubicadas en varios estados del país. Las deficientes condiciones sanitarias de producción, almacenamiento, transporte y comercialización para este producto, son causas importantes de contaminación con microorganismos entre los que pueden

José Gregorio Márquez

274

MERCADO DEL CAFÉ EN MÉXICO  

Microsoft Academic Search

La producción de café en México ostenta amplia relevancia tanto en el plano económico como social. El trabajo se centra en las características del grano de café que podrían aprovecharse, junto con otras estrategias para incrementar su consumo. Por esta razón se realizó un análisis de las estadísticas de oferta y demanda para el café consumido en el país, en

Gustavo Guerra G; Leoncio Reyes B; Juan Ruiz-Ramírez

2012-01-01

275

Variabilità interannuale del fi toplancton del Lago di Tovel (Trentino, Italia)  

Microsoft Academic Search

RIASSUNTO - Variabilità interannuale del fi toplancton del Lago di Tovel (Trentino, Italia) - Lo studio del fi toplancton del Lago di Tovel nel periodo 2002-2004 ha avuto come principali obiettivi l'analisi della variabilità interannuale delle dinamiche stagionali nel Bacino Principale e nella Baia Rossa, il confronto tra le associazioni fi toplanctoniche attuali e passate (prima e dopo la scomparsa

Monica TOLOTTI; Dámaso CALLIARI; Flavio CORRADINI

276

Boletín del Instituto Nacional del Cáncer - 4 de enero de 2011  

Cancer.gov

En esta edición especial del Boletín del Instituto Nacional del Cáncer, usted conocerá las diversas formas en que el NCI está apoyando los esfuerzos de colaboración internacional en las áreas de investigación, capacitación, comunicación y demás actividades relacionadas con una mejor comprensión del cáncer y el tratamiento de pacientes con esta enfermedad.

277

ECONOMIA, VALORIZZAZIONE, GESTIONE DEL PATRIMONIO TURISTICO  

E-print Network

ECONOMIA, VALORIZZAZIONE, GESTIONE DEL PATRIMONIO TURISTICO Giovedì 23 Giugno 2011 Giovedì23 Giugno 2011 ore 09.00 Presentazione del corso di laurea Aula A Facoltà di Economia UNIVERSITA'DEGLI STUDI DI SALERNO #12;Il corso di laurea interateneo, Economia, Valorizzazione, Gestione del Patrimonio Turistico

Costagliola, Gennaro

278

Uso del Los SIG en ModelosUso del Los SIG en ModelosUso del Los SIG en Modelos Hidrolgicos y de Calida de Agua  

E-print Network

Calida de Agua Uso del Los SIG en Modelos Hidrol�gicos y de Calida de Agua (Caso de Uso Cuenca del Ri Luis R. P�rez-Alegr�a PhD P.E.Luis R. P�rez-Alegr�a PhD P.E. #12;Usos del AguaUsos del AguaUsos del AguaUsos del Agua Navegaci�n Consumo Humano HigieneHigiene PescaRecreaci�n #12;Calidad del Agua

Gilbes, Fernando

279

MSTER UNIVERSITARIO EN DIRECCIN INTERNACIONAL DEL TURISMO HORARIOS DEL CURSO 2014-2015 CAMPUS DE FUENLABRADA  

E-print Network

:00 19:00-20:00 Economía del turismo internacional: impactos y modelos Sistemas y Tecnología Economía del turismo internacional: impactos y modelos Sistemas y Tecnología Economía del turismo internacional:00-20:00 Economía del turismo internacional: impactos y modelos Sistemas y Tecnología Economía del turismo

Rey Juan Carlos, Universidad

280

Boletín del Instituto Nacional del Cáncer - 03-02-2010  

Cancer.gov

Algunas mujeres con cáncer de ovarios reportan síntomas que incluyen dolor abdominal, meteorismo y sensación de llenura antes de que haya un diagnóstico. Pero un estudio nuevo concluye que vigilar estos síntomas relativamente inespecíficos en las mujeres tendría un valor limitado en la detección de la enfermedad. Los médicos tendrían que evaluar a 100 mujeres con estos síntomas para encontrar un cáncer de ovarios, informaron los investigadores en Internet en la revista Journal of the National Cancer Institute del 28 de enero.

281

Malattie cistiche del parenchima renale  

Microsoft Academic Search

\\u000a La malattia cistica del parenchima renale rappresenta un eterogeneo gruppo di malattie a carattere congenito, ereditario e\\u000a non, e acquisito caratterizzate dalla presenza di formazioni cistiche. Il riscontro di formazioni cistiche renali è molto\\u000a frequente nella pratica clinica quotidiana. Solo un’adeguata conoscenza degli aspetti anatomopatologici permette la giusta\\u000a comprensione delle manifestazioni cliniche e la corretta interpretazione dei reperti radiologici. Compito

Fulvio Stacul; Marco F. Cavallaro; Maria A. Cova

282

Lecciones del de comerciode la  

E-print Network

Udios china-méxico © 2011 Por características tipográficas y de diseño editorial miGUel ÁnGel porrúa, librero Estudios del Desarrollo Universidad nacional aUtónoma de méxico, Centro de Estudios China-México t Desarrollo Económico y Social (Brasil) cafta: Tratado de Libre Comercio de Centro América (Republica

Tufts University

283

Recensin del libro: Modelos Matemticos  

E-print Network

Recensión del libro: Modelos Matemáticos Rafael Ortega Ríos (Aparecerá en la Revista Española de Física) Este libro, breve, elegante y lleno de buen gusto matemático, me parece muy recomendable para de aplicación; cuanto se necesita está claramente expuesto en el mismo libro. Hay cuatro capítulos

Sanz-Serna , J M

284

L'avifauna del Laghetto del Frassino (Peschiera del Garda, Verona, Veneto)  

Microsoft Academic Search

Ten years of ornithological research at Lake Frassino (located near Peschiera del Garda, Verona, Italy) have produced a check-list of the birds dwelling at this Site of Community Importance (S.I.C.) to be produced. Our surveys have revealed that this water basin where ducks stop al- most exclusively during the day represents, together with nearby Lake Garda, the most important wintering

MARCO MORBIOLI; MAURIZIO SIGHELE

285

Dr. Matas Alvarado (CV breve) Investigador Titular del Departamento de Computacin del CINVESTAV, Miembro Regular de  

E-print Network

Dr. Mat�as Alvarado (CV breve) Investigador Titular del Departamento de Computaci�n del CINVESTAV� Mat�as Alvarado Mentado Curriculum Vitae CURRENT POSITION Research Scientist (Investigador CINVESTAV 3

Alvarado, Matías

286

Turismo de masas y transporte: el gran reto del turismo del siglo XXI  

Microsoft Academic Search

El turismo masas es una de las grandes consecuciones del estado del bienestar, al tiempo que ha venido generando una actividad económica importante. En este contexto, el turismo internacional aumentó un 50 por ciento en los años noventa. Es cierto que la tecnología ha avanzado mucho para evitar los impactos que esta movilidad genera, si bien el aumento del turismo

José Ángel Hernández Luis

2008-01-01

287

Manual de montaje del Telescopio Solar  

E-print Network

telescopio (LUNT 102 mm H) · Tapa del tubo · Tapa del prisma · Prisma · Buscador (instalado) · Ocular Zoom: (7.2 ­ 21.5 mm) · Tapas (x2) · Anillas para electrónica 8. Quitar tapas 9. Poner ocular 10.Alargar tubo 11.Colocar Parasol 12

288

Control del dolor: Apoyo para las personas con cáncer  

Cancer.gov

Libro sobre el control del dolor en pacientes con cáncer. Cubre los métodos y medicinas, así como los efectos físicos y emocionales del dolor. Es una adaptación cultural para el público de habla hispana del libro en inglés Pain Control.

289

Clausura de curso del Mster en Gestin Sostenible y Tecnologas del Agua de la Universidad de Alicante  

E-print Network

Clausura de curso del Máster en Gestión Sostenible y Tecnologías del Agua de la Universidad de el Tratamiento del Agua (ATTA) pronunciará la ponencia de clausura Finaliza el curso de los estudios oficiales del Máster en Gestión Sostenible y Tecnologías del Agua de la UA que imparte el Instituto del Agua

Escolano, Francisco

290

¿Cómo puedo usar los servicios del CIS?  

Cancer.gov

El Servicio de Información sobre el Cáncer del Instituto Nacional del Cáncer maneja también la línea telefónica para dejar de fumar 1-877-448-7848 (1-877-44U-QUIT), la cual proporciona información gratuita para dejar de fumar y apoyo a fumadores que desean dejar el tabaco. Nuestro servicio no tiene ningún costo ni cuota de pago. El servicio se brinda en inglés y en español, de lunes a viernes de 8 de la mañana a 8 de la noche, hora del Este.

291

Produccion Gaseosa del Cometa Halley: Erupciones Y Fotodisociacion del Radical OH  

NASA Astrophysics Data System (ADS)

RESUMEN:En este trabajo informamos la detecci6n de 20 erupciones en la li'nea de =18cm (1667MHz) del radical OH en el Cometa Halley.Las observaciones incluyen todos los monitoreos existentes y se extienden desde 120 dias antes del perihelio hasta 90 dias despues.Se detectan bruscos crecimientos en el flujo medido,hasta un factor 1O,seguidos por decaimientos lentos asociados con la fotodisociaci6n del OH. Se obtuvieron valores para el tiempo de vida fotoquimico del OH y del H2O basandose en el modelo desarrollado previamente por Silva(1988). Esos tiempos de vida estan de acuerdo con predicciones teoricas y con las observaciones en el Ultravioleta, y los resultados, los que son fuertemente dependientes de la velocidad heliocentrica del Coineta (variando hasta un factor 6), han sido calculados para varios rangos de velocidad entre +28 y -28 km/seg. Key wo'L :

Silva, A. M.; Mirabel, I. F.

1990-11-01

292

28 de mayo del 2007 Curriculum Vitae  

E-print Network

de la Organizaciâ??on de Estados Americanos. 1987 Premio Dudley del Observatorio Dudley. 1988 Becaâ??es Organizadores de las Siguientes Reuniones (29): Symposium on Herbig­Haro Objects, T Tauri Stars and Related

Rodriguez, Luis F.

293

28 de mayo del 2007 Curriculum Vitae  

E-print Network

de la Organizaci´on de Estados Americanos. 1987 Premio Dudley del Observatorio Dudley. 1988 Beca´es Organizadores de las Siguientes Reuniones (29): Symposium on Herbig-Haro Objects, T Tauri Stars and Related

Rodriguez, Luis F.

294

Modelo Hidrulico Operacional del Oeste de Puerto Rico  

E-print Network

Puerto Rico Introducción El Instituto de Investigaciones Sobre Recursos de Agua y el Ambiente de Puerto del Modelo Hidráulico Operacional del Sistema de Distribución de Agua del Oeste de Puerto Rico. El agua. · Reserva Nodos que representan una fuente de agua externa del sistema. · Tanques Nodos con

Gilbes, Fernando

295

Departamento de Filosofa del Derecho y Derecho Internacional Privado Presentacin  

E-print Network

Departamento de Filosofía del Derecho y Derecho Internacional Privado Presentación El Departamento de Filosofía del Derecho y Derecho Internacional Privado está compuesto por las siguientes áreas de personalizada, los profesores del Departamento de Filosofía del Derecho y Derecho Internacional Privado ruegan

Escolano, Francisco

296

MONITOR DE CICLO INDOOR OBJETIVOS DEL CURSO  

E-print Network

positivos y posibles perjuicios que puede tener la práctica del ciclo indoor e indoor walking sobre la salud Julián Álvarez García, Médico, Especialista en Medicina de la EF y el Deporte, Doctor en Medicina, Experto en Fisiología del Ejercicio, Profesor de Medicina Deportiva de la UMH, Asesor médico de la

Escolano, Francisco

297

Cronología acotada de la década del '80  

E-print Network

Alezzo. Teatro Regina. (Abril) Marathón, de Ricardo Monti. Dirección: Jaime Kogan. Teatro: Los teatros de San Telmo. La puesta estuvo a cargo del Equipo del Teatro Payró. La ubicamos como textualidad emergente de los '70. Es una alegoría con... discurso marginal de la radio y la historieta. Con este intertexto más el material que le proporcionan las películas de una época, recrea un mundo de nostalgia: el paso de la niñez a la adolescencia. (Agosto) Extraño juguete, de Susan Torres Molina...

Cazap, S.; Giustachini, A.; Massa, C.; Semelman, A.; Sikora, Marina F.

1991-04-01

298

La evolucion del modernismo en Puerto Rico  

E-print Network

metros e hizo uso del encabal- gamiento y de la cesura en mitad de sus versos, cambiando asi el antiguo romance (Franco 151). Ademas, Dario resucito la cuaderna via medieval y el verso alejandrino. Ruben Dario descubrio nuevas posibilidades foneticas... metros e hizo uso del encabal- gamiento y de la cesura en mitad de sus versos, cambiando asi el antiguo romance (Franco 151). Ademas, Dario resucito la cuaderna via medieval y el verso alejandrino. Ruben Dario descubrio nuevas posibilidades foneticas...

Gonzalez-Hernandez, Miriam Mercedes

2012-06-07

299

MANUAL TELESCOPIO MONS OBSERVATORIO DEL TEIDE  

E-print Network

electr´onica Se trata de una funci´on del operardor nocturno (Ap´endice C). 1.2. Tapas de la ´optica Para proteger la ´optica del telescopio hay dos tapas, una para el telescopio principal y otra para el buscador. La maniobra para quitarlas o colocarlas tiene cierto peligro, debido a que el peso de ambas tapas

300

Orígenes y desarrollo del teatro guatemalteco.  

E-print Network

teatral bifurcado en dos corrientes muy definidas—la de nuestro mundo indígena y la de nuestro mundo mestizo. La primera se desborda por los pueblos del interior del país, a la sombra de las iglesias, en los patios de las alcaldías municipales o en las... sutil, más amable por menos sangriento, pero muy eficaz para lograr la total cristianización de aquellos pueblos, apareció el teatro inmediatamente después de la conquista. Se adaptaron las danzas locales, 42 LATIN AMERICAN THEATRE REVIEW...

Carrillo, Hugo

1971-10-01

301

Calidad de Imagen del Telescopio UNAM212  

NASA Astrophysics Data System (ADS)

El telescopio UNAM2l2, del Observatorio Astronómico Nacional, situado en la Sierra de San Pedro Mártir (Baja California, México), cumplira en un futuro muy cercano siete años de uso para fines de investigación astronómica. Aunque en este tiempo no se ha efectuado un estudio sistemático acerca de su comportamiento óptico y de los factores que influyen en la calidad de las imágenes, se han realizado pruebas diversas, estudios parciales y reuniones especificas, cuyos resultados no siempre se han difundido ampliamente y generalmente no se han presentado por escrito. Es por ello que hemos creido necesario intentar una recopilación de la información existente para poder con ella establecer un diagnóstjco que, aunque no sea definitivo, sirva de base para futuros trabajos tendientes a optimizar el comportamiento óptico del telescopio. Es evidente que un buen número de las conclusiones que se presentan son resultado del trabajo de muchas personas ó de esfuerzos colectivos. Asimismo, hemos tratado de localizar información bibliográfica que pueda ser de utilidad. Nuestro objetivo primordial ha consistido en centrarnos en la óptica del telescopio y su calidad, pero también se han considerado otros aspectos que puedan afectar las imágenes obtenidas tales como: celda del primario, `seeing' local y externo, flexiones posibles en la estructura mecánica del telescopio, etc.

Cobos, F. J.; Teiada de Vargas, C.

1987-05-01

302

Precio del agua y relocalización del recurso en la economía andaluza. Una aproximación desde un modelo de equilibrio general aplicado  

Microsoft Academic Search

El objetivo de este trabajo consiste en analizar los efectos que tendría un incremento en la tarifa del agua del sector agrario sobre la conservación del recurso, la eficiencia en el consumo y la posible relocalización del mismo entre los diferentes sectores productivos. La política tarifaria se aplicará sobre el sector agrario debido, por un lado, al excesivo consumo de

M. Alejandro Cardenete; G. J. D. Hewings; E. Velázquez

2005-01-01

303

O Diagnostico do Curso de Farmacia da UNIMEP (Diagnosis of the Pharmacy Course of UNIMEP).  

ERIC Educational Resources Information Center

Reports on the experience of the pharmacy course at UNIMEP (Methodist University of Piracicaba (Brazil)) in diagnosing itself. Offers models for the elaboration of an innovative curriculum which is the desire of those who make up the course. (BT)

Fontes, Olney Leite; do Carmo, Thais Adriana; Polacow, Maria Luiza O.; Meneghetti, Rosa Gitana K.; Dedalo, Maria de Fatima Nepomuceno; Alves, Maria Izalina F.; da Silva, Jadson Oliveira; Carvalho, Maria Eliza C.

2000-01-01

304

Schwannoma do nervo vestibular (neurinoma do acustico) : diagnostico e tratamento com variação da abordagem cirurgica.  

E-print Network

??O autor apresenta um estudo descritivo-retrospectivo, envolvendo 240 pacientes portadores de Schwannoma do Vestibular (SV) que foram operados em decúbito dorsal (posição de mastóide), monitorizados… (more)

Arquimedes Cavalcante Cardoso

2007-01-01

305

Dr. Matas Alvarado (CV breve) Investigador Titular del Departamento de Computacin del CINVESTAV; Miembro Regular de  

E-print Network

Dr. Matías Alvarado (CV breve) Investigador Titular del Departamento de Computación del CINVESTAV. JOS� MATÍAS ALVARADO MENTADO Curriculum Vitae DATOS PROFESIONALES Investigador CINVESTAV 3B (Febrero JCR ISI 1. Alvarado Matias, Sheremetov, L., Bañares, R. & Cantú, F. (Guest Eds.) Special Issue

Alvarado, Matías

306

Preguntas y respuestas acerca del Estudio del Tamoxifeno y Raloxifeno (STAR)  

Cancer.gov

El Estudio del Tamoxifeno y Raloxifeno (STAR, por sus siglas en inglés) es un estudio clínico (un estudio de investigación conducido con voluntarios) diseñado para ver cómo el medicamento raloxifeno (Evista®) se compara con el medicamento tamoxifeno (Nolvadex®) en reducir la incidencia de cáncer del seno en las mujeres con alto riesgo de desarrollar la enfermedad.

307

DECISIONES DE FINANCIACIÓN DE LA INDUSTRIA METALMECÁNICA DEL VALLE DEL CAUCA  

Microsoft Academic Search

Esta investigación tiene como objetivo conocer los factores que influyen en la toma de decisiones de financiamiento a largo plazo en la industria metalmecánica del Valle del Cauca (Colombia), hasta ahora no explorados. Se realiza un estudio para el periodo 2000-2006, utilizando como método, el análisis de la estructura financiera y la aplicación de un modelo econométrico de Datos de

JORGE ALBERTO RIVERA GODOY

2008-01-01

308

Localización del Esfuerzo de Pesca en la Pesquería Chileno-Transzonal del Jurel (Trachurus murphyi)  

Microsoft Academic Search

Este trabajo analiza condicionantes de la localización del esfuerzo pesquero de la flota chilena que opera en la pesquería transzonal del Jurel, considerando datos por viaje para el periodo 1987-2004. Desde principios de los años 1990s esta flota comenzó a desplazarse más allá de las 200 mn, condicionada por cambios en la distribución espacial de este recurso. Se presume que

Julio Peña Torres; Mabyr Valderrama

2008-01-01

309

Boletín del Instituto Nacional del Cáncer - 3 de enero de 2012  

Cancer.gov

Dra. Rachel Ballard-Barbash Nuevos indicios del papel de la obesidad en el cáncer A medida que ha aumentado la prevalencia de la obesidad alrededor del mundo, se ha incrementado también la preocupación sobre sus consecuencias en la salud pública. Los índices de obesidad se han más que duplicado desde 1980, según la Organización Mundial de la Salud.

310

Impacto economico del turismo en el Mercosur y Chile (1990-2000)  

Microsoft Academic Search

El objetivo del presente trabajo consiste en describir la situacion del turismo actual y analizar la evolucion del turismo receptivo en la region del MERCOSUR y Chile en la decada de los noventa. Tambien se propone un modelo econometrico que recoge el impacto positivo del turismo en el crecimiento del PIB del sector servicios. This paper describes present situation of

Rodrigo Gardella; Eva Aguayo

2002-01-01

311

III Festival del Siglo de Oro (Chamizal)  

E-print Network

SPRING 1978 111 III Festival del Siglo de Oro (Chamizal) E. JARABA-PARDO El Siglo de Oro fue, por la fecundidad de los autores y por las influencias trascendentales de sus obras en el posterior desarrollo de la dramaturgia universal, uno de los... todos los actos de los hombres son guiados por Dios, quien se muestra como supremo hacedor de todo cuanto acontece a las criaturas. Se encuentran, pues, en síntesis en el teatro del Siglo de Oro unos valores particularmente antagónicos de la sociedad...

Jaraba-Pardo, E.

1978-04-01

312

El Servicio de Información sobre el Cáncer del Instituto Nacional del Cáncer  

Cancer.gov

El Servicio de Información del Cáncer (CIS) del Instituto Nacional del Cáncer facilita la información más actualizada y precisa sobre el cáncer a pacientes, a sus familias, al público en general y a profesionales médicos. El CIS brinda respuestas personalizadas a preguntas específicas sobre el cáncer y asistencia a los fumadores que quieren abandonar el hábito. Comuníquese con el CIS al 1-800-422-6237 (1-800-4-CANCER) o al 1-877-448-7848 (1-877-44U-QUIT).

313

La reconstrucción del seno después de una mastectomía  

Cancer.gov

Hoja informativa que describe la reconstrucción del seno (mama) después de una mastectomía. Contiene información sobre las opciones quirúrgicas, los cuidados de seguimiento y los exámenes de detección del cáncer de seno después de la reconstrucción.

314

Research in Automated Reasoning Alvaro del Val  

E-print Network

Research in Automated Reasoning Alvaro del Val E.T.S. Inform´atica Universidad Aut´onoma de Madrid, and then using reasoning algorithms to extract consequences from that knowledge. Knowledge representation deals with the issue of defining languages suitable for various domains and reasoning tasks; automated reasoning

Autonoma de Madrid, Universidad

315

GEOGRAFAAGRARIA (1 parte del Tema 1)  

E-print Network

;Diferenciación de los paisajes agrarios Usos del suelo Técnicas de riego empleadas Formas y tamaños de las (suelos y climas), biológicos (cultivos) y culturales sobre un espacio económico no urbano de la

Escolano, Francisco

316

Le origini del mondo Giuseppe Longo  

E-print Network

Bang: T= 0 (17.000.000.000 anni fa) La storia di una lenta morte termica ? L'energia totale dell ogni grandezza fisica Q diminuisce con il volume V R età = t 1/R3 1/t3 La densità di energia #12;Le origini #12;Formazione del sistema solare storia Geologia Fisica Chimica Biologia Fisica dell

Santorelli, Pietro

317

ECONOMÍAS EXTERNAS Y LOCALIZACIÓN DEL EMPLEO INDUSTRIAL  

Microsoft Academic Search

Es un hecho fácilmente constatable que la actividad económica en gene- ral e industrial en particular se localiza de forma desigual a lo largo de la geografía española. El presente trabajo plantea un modelo que tiene como objetivo analizar la incidencia de las economías externas en la dis- tribución territorial del empleo de los distintos sectores industriales. El modelo incorpora

ELISABET VILADECANS MARSAL

2003-01-01

318

MINOR DE COMPUTACION CIENTIFICA Nombre del Minor  

E-print Network

SCT CC3001 Algoritmos y estructuras de datos 10 FI3104 Métodos numéricos para la ciencia e ingeniería. Código Nombre CC3001 Algoritmos y estructuras de datos Nombre en Inglés Algorithms and data structures Aprendizaje Al termino del curso se espera que el estudiante conozca, aplique y analice las estructuras de

Rapaport, Iván

319

SPTIMA EDICIN Del 18 de marzo al  

E-print Network

de Seguridad de la Universidad Rey Juan Carlos. Profesor: D. Daniel Campos Navas. Fiscal de la Seguridad. CTC 3. Caso práctico Profesor: D. Andrés Martínez Calvo. Secretaría General delTesoro y Política

Rey Juan Carlos, Universidad

320

Uso Eficiente del Agua en Ingenios Azucareros  

Microsoft Academic Search

El impacto que produce el alto consumo de agua en regiones donde este recurso es limitado, alienta al desarrollo de nuevas técnicas que permitan analizar la administración eficiente del agua en las industrias y que comúnmente se concreta realizando balances detallados para diferentes configuraciones propuestas de uso de agua. En este trabajo se presenta una metodología alternativa, mediante el cálculo

Alejandra Ingaramo; Humberto Heluane; Mauricio Colombo; Tomás Argüello; Mario Cesca

321

Exámenes selectivos de detección del cáncer colorrectal  

Cancer.gov

Un ejemplo excelente del poder de la investigación de prevención es el progreso sustancial que hemos logrado en la reducción de la incidencia y muerte por cáncer colorrectal, con nuevos conocimientos que iluminan el camino a incluso mayores reducciones en un futuro cercano.

322

Facultad de Derecho DATOS DEL ALUMNO  

E-print Network

Facultad de Derecho DATOS DEL ALUMNO APELLIDOS 1º 2º NOMBRE NIF DIRECCI�N LOCALIDAD CP PROVINCIA EMAIL TFNO. FIJO TFNO. MOVIL IMPORTANTE Para obtener los correspondientes títulos de Derecho y ADE, el elección, con los siguientes requisitos: - Los créditos de libre elección necesarios son 30,5 para Derecho

Escolano, Francisco

323

Boletín del Instituto Nacional del Cáncer - 22 de mayo de 2012  

Cancer.gov

Le invitamos a que comparta esta publicación con sus amigos, familiares y colegas y nos ayude a continuar nuestra misión de difundir las investigaciones más recientes sobre la prevención, el tratamiento y la información del cáncer.

324

Boletín del Instituto Nacional del Cáncer - 19 de julio de 2011  

Cancer.gov

Le invitamos a que comparta esta publicación con sus amigos, familiares y colegas y nos ayude a continuar nuestra misión de difundir las investigaciones más recientes sobre la prevención, el tratamiento y la información del cáncer.

325

Boletín del Instituto Nacional del Cáncer - 24 de abril de 2012  

Cancer.gov

Le invitamos a que comparta esta publicación con sus amigos, familiares y colegas y nos ayude a continuar nuestra misión de difundir las investigaciones más recientes sobre la prevención, el tratamiento y la información del cáncer.

326

Boletín del Instituto Nacional del Cáncer - 11 de octubre de 2011  

Cancer.gov

Le invitamos a que comparta esta publicación con sus amigos, familiares y colegas y nos ayude a continuar nuestra misión de difundir las investigaciones más recientes sobre la prevención, el tratamiento y la información del cáncer.

327

Boletín del Instituto Nacional del Cáncer - 8 de noviembre de 2011  

Cancer.gov

Le invitamos a que comparta esta publicación con sus amigos, familiares y colegas y nos ayude a continuar nuestra misión de difundir las investigaciones más recientes sobre la prevención, el tratamiento y la información del cáncer.

328

Boletín del Instituto Nacional del Cáncer - 27 de marzo de 2012  

Cancer.gov

Le invitamos a que comparta esta publicación con sus amigos, familiares y colegas y nos ayude a continuar nuestra misión de difundir las investigaciones más recientes sobre la prevención, el tratamiento y la información del cáncer.

329

Crecimiento del PIB vs. Consumo de Energa (variacin % respecto del ao base 1990)  

E-print Network

2 3 4 #12;5 Crecimiento del PIB vs. Consumo de Energía (variación % respecto del año base 1990) 0 Coal Nuclear Energy Hydro electric 16 #12;17 Venezuela Santiago Existing pipeline Planned pipeline% Diesel-fuel oil 13% Hydro 39% Natural gas 36% Coal 18% Others 2% Diesel-fuel oil 5% 19 Sistema MW % SING

Catholic University of Chile (Universidad Católica de Chile)

330

Boletín del Instituto Nacional del Cáncer - 31 de enero de 2012  

Cancer.gov

Dr. Nils Daulaire Salud mundial a través de la colaboración y el liderazgo Para conmemorar el Día Mundial del Cáncer que tuvo lugar el 4 febrero, el doctor Nils Daulaire, director de la Oficina de Asuntos Internacionales del Departamento de Salud y Servicios Humanos de los Estados Unidos habla sobre las razones por las cuales los Estados Unidos deben participar en iniciativas para mejorar la salud mundial.

331

Análisis del Proceso Software Basado en Modelos de Producción Industrial  

Microsoft Academic Search

La modelización del Proceso Software constituye un marco de referencia para la organización de las actividades que involucran todas las etapas del desarrollo, tendente a la resolución de problemas que el propio desarrollo de software plantea y genera a medida que evoluciona. La modelización del proceso se hace mas compleja a medida que el desarrollo tecnológico, metodológico y, fundamentalmente la

Alicia Mon

332

Lecturas sobre derecho del medio ambiente t. IV  

Microsoft Academic Search

Explorando los algunos aspectos vulnerables del derecho del medio ambiente, se tratan, entre otros, las responsabilidades civiles de aquellos que menoscaban nuestro hábitat, y del aseguramiento que se debe tener para el transporte y almacenamiento de desechos peligrosos, no solo a la luz de la legislación colombiana, sino de la argentina, chilena y española.

Autores varios

333

Piano Lauree Scientifiche: Aspetti matematici del Rudiger Achilles  

E-print Network

Bologna, 3 Febbraio 2014 3 / 19 #12;GPS III SATELLITE Piano Lauree Scientifiche: Aspetti matematici delPiano Lauree Scientifiche: Aspetti matematici del GPS R¨udiger Achilles Universit`a di Bologna Bologna, 3 Febbraio 2014 Piano Lauree Scientifiche: Aspetti matematici del GPS R¨udiger Achilles Bologna

Achilles, Rüdiger

334

Economía del narcotráfico, Plan Colombia y conflicto interno en Colombia  

Microsoft Academic Search

El artículo presenta una semblanza del entorno político reciente que compromete una dimensión de las estrategias de la lucha contra las drogas; un mapa del mercado de narcóticos, especialmente centrado en el de cocaina; los fundamentos de la estrategia de lucha contra el narcotráfico y los elementos de su crísis; la dimensión del Negocio de la cocaína, considerando una cuantificación

Olmedo Vargaz Hernández

2005-01-01

335

Estructura y paleogeografa de los materiales del Trisico en la terminacin meridional del Arco de Cazorla (Jan, Cordillera  

E-print Network

243 Estructura y paleogeografía de los materiales del Triásico en la terminación meridional del relleno de la cuenca del Guadalquivir. La dirección de la ma- yor parte de las estructuras en la Sierra de del Arco y sobre la evolución de esta gran estructura, donde existen importantes accidentes que delimi

Herrera, Carlos M.

336

Publicaciones del IGME: serie Hidrogeologa y aguas subterrneas, n 14. VI Simposio del Agua en Andaluca. I: 669-678  

E-print Network

Publicaciones del IGME: serie Hidrogeología y aguas subterráneas, nº 14. VI Simposio del Agua en Andalucía. I: 669-678 Problemática de la calidad de las aguas de la Vega de Granada para el riego del tabaco Castillo Martín, Antonio* y Sánchez Díaz, Luis** * CSIC e Instituto del Agua de la Universidad de Granada

Castillo, Antonio

337

Estudio para la prevención del cáncer necesita voluntarias: El Estudio del Tamoxifeno y Raloxifeno (STAR) se realiza en Norteamérica  

Cancer.gov

El Estudio del Tamoxifeno y Raloxifeno (STAR, por sus siglas en inglés), uno de los estudios más importantes realizados para la prevención del cáncer del seno, está ahora reclutando voluntarias en más de 400 centros en los Estados Unidos, Puerto Rico y Canadá.

338

Anatomia delle componenti ossee dell'ATM; Anatomia del disco articolare;  

E-print Network

· Anatomia delle componenti ossee dell'ATM; · Anatomia del disco articolare; · Anatomia del tessuto retrodiscale; · Anatomia dei legamenti capsulari ed extra capsulari; · Anatomia del muscolo; · Anatomia del nervo trigemino; · Anatomia del nervo facciale; · Anatomia del nervo ipoglosso

Di Pillo, Gianni

339

El Sexto Festival de Teatro Español del Siglo de Oro  

E-print Network

SPRING 1981 79 El Sexto Festival de Teatro Español del Siglo de Oro Arturo Pérez-Pisonero El Sexto Festival de Teatro Español del Siglo de Oro, celebrado en el Chamizal National Memorial en las fechas del 6 al 22 de marzo, ha presen tado, como... ofrece el teatro del Siglo de Oro. Y en tusiasmo, en este caso genuino, ha sido el del público, quien unas noches ha aplaudido los aciertos, y otras, como aquel otro de los corrales, se ha burlado jocosamente de la impericia de los actores. Pero al...

Pé rez-Pisonero, Arturo

1981-04-01

340

Albedo polarimétrico de asteroides del grupo Hungaria  

NASA Astrophysics Data System (ADS)

La región del cinturón de asteroides en donde se encuentra el grupo de los Hungarias (a= 1.79 a 1.98 UA, i=15 a 40 grados) es la única zona donde es común encontrar objetos de tipo taxonómico E, caracterizados por altos albedos, colores relativamente neutros y espectros sin detalles. Este tipo de asteroides está relacionado espectralmente con ciertos meteoritos (aubritas) que indican la existencia de episodios de gran calentamiento que ocurrieron durante la formación del Sistema Solar. Como el espectro de los asteroides de tipo E es idéntico a los de tipo M y P, la única forma de clasificar un asteroide en alguno de estos tres tipos taxonómicos es mediante el albedo. En este trabajo se presentan resultados preliminares sobre la determinación polarimétrica de albedos para objetos de este grupo utilizando el polarímetro CASPROF de CASLEO.

Gil-Hutton, R.; Benavidez, P.

341

Una década de búsqueda del teatro hondureño  

E-print Network

colectiva, y por la efervescencia política de la época. De tres grupos se destacan: El Teatro Experimental la Merced (TEUM); El Teatro Obrero del Pueblo Unido (TOPU); y Teatro Popular Universitario (TPU). En estos grupos actúan jóvenes que despuntarán... de teatro popular e intento para generar una plataforma artística y de política cultural a tono con esa época de transformaciones sociales en Centroamérica. Su eslogan mismo, "Por SPRING 1992 109 un nuevo teatro para una nueva sociedad," fue punto...

Reyes G., Candelario

1992-04-01

342

ENERGIA DEL SOL Ts = 5780 K  

E-print Network

ENERGIA DEL SOL Ts = 5780 K P = 3, 86 � 1026 W Constant solar = 1377 W/m2 4H1 + 2e- He4 + 2 utilitzar per a aprofitar l'energia solar. #12;LA RADIACI´O SOLAR #12;LA RADIACI´O SOLAR #12;#12;#12;LA;APROFITAMENT DE LA RADIACI´O SOLAR La radiaci´o solar la podem convertir en altres formes d'energia per

Batiste, Oriol

343

Concentración del fragmento aminoterminal del pro-péptido natriurético cerebral en plasma como marcador biológico predictivo de mortalidad en las neumonías adquiridas en la comunidad.  

E-print Network

??Objetivo: Evaluar la relación entre la concentración plasmática del fragmento aminoterminal del pro-péptido natriurético cerebral (NT-proBNP) en el momento del diagnóstico de neumonía adquirida en… (more)

Tazón Varela, Manuel Antonio

2014-01-01

344

DERECHOS DEL EMPLEADO LEy PARA LA PROtECCin  

E-print Network

DERECHOS DEL EMPLEADO LEy PARA LA PROtECCión DEL EMPLEADO COntRA LA PRuEbA DEL POLígRAfO PROHIBICIONES ExENCIONES DERECHOS DE LOS ExAMINADOS CUMPLIMIENTO Generalmente se le prohíbe al empleador que le aspirante a un trabajo por haberse negado a someterse a la prueba o por haberse acogido a otros derechos

Rock, Chris

345

julio-septiembre2006Cinvestav74 Resea del libro  

E-print Network

julio-septiembre2006·Cinvestav74 Reseña del libro Ejemplos prácticos del uso de la resonancia Departamento de Química en 1993, conocería personalmente a todos los autores del libro. En algunas ocasiones comenté con ellos la dificultad de encontrar libros de texto en los que se abordaran ejemplos reales

346

An evening at "La Clinica del Pueblo".  

PubMed

This article describes a typical evening at the Clinica del Pueblo in the Hispanic neighborhood of Adams-Morgan in Washington, D.c. The Clinical del Pueblo began operating in 1983 in response to the urgen medical needs of Central American refugees arriving in the Washington D.c. area. The refugees bring with them severe trauma, fear, and health problems caused by the civil was and exacerbated by inadequate or non-existant health services. Approximately 80,000 Salvadoran refugees live in the area. They do not receive adequate health care for 3 reasons. 1) Because the US goverment is unwilling to recognize them as true refugees, they live with the constant threat of deportatin back to the violence from which they have fled. 2) Refugees lack the ability to pay for private care. 3) Langauage and culture create frightening barriers to health care for the refugees. For those who do seek care, these barriers can lead to the inadequate or incomplete diagnoses and poor compliance and follow-up. Plenty International and the Central American Refugee Center responded to these problems by organizing a free clinic to provide not only medical care but also a training course for volunteers. The director of the clinic organizes the course, the classes are taught by a variety of people including the clinic's volunteer physicians, nurses, and public health educators as well as graduates of previus training courses and people from the wider community. The services of the clinic reach only a small portion of the population in need. However, the fact that free medical services are now available to some Central American refugees make the Clinica del Pueblo an important program. PMID:12281149

Shefsky, M L

1986-01-01

347

RELACIÓN MÉDICO PACIENTE: DERECHOS DEL ADULTO MAYOR  

PubMed Central

Existen prejuicios en relación con la vejez, incluso entre los profesionales que se dedican a la gerontología. Uno común y peligroso es considerar que los viejos son todos enfermos o discapacitados. La relación médico-paciente es la piedra angular de la práctica y ética médicas. Para alcanzar el respeto por los adultos mayores es necesaria una medicina prudente, basada en una práctica en la cual la reflexión ética y clínica pueda contribuir. Esto último es posible si se hacen valer los derechos del adulto mayor, en particular como paciente para la toma de decisiones. PMID:20379380

Barrantes-Monge, Melba; Rodríguez, Eduardo; Lama, Alexis

2009-01-01

348

Boletín del Instituto Nacional del Cáncer - 11 de septiembre de 2012  

Cancer.gov

Con la ayuda de herramientas genéticas, investigadores han identificado subconjuntos de células que parecen impulsar el crecimiento de tumores en ratones. Estos resultados ofrecen factores adicionales que sustentan la hipótesis de la existencia de células madre del cáncer, es decir, la idea de que algunos tumores contienen células que se autorenuevan y dan origen a todo tipo de células tumorales.

349

Análisis del dispositivo de balón coil para la oclusión del Ductus Arterioso Persistente  

Microsoft Academic Search

RESUMEN: El ductus arterioso persistente (PDA) es uno de los defectos cardiacos congénitos más comunes. Consiste en una comunicación vascular anormal durante la vida extrauterina, entre la aorta descendente y la arteria pulmonar izquierda. El PDA puede llevar al desarrollo de complicaciones importantes como hipertensión pulmonar, edema pulmonar y endocarditis bacteriana. Actualmente el manejo del PDA se hace por medio

A. C. Silva; J. C. Briceño; A. García

350

V Festival Nacional del Nuevo Teatro: Las fuentes inagotables del arte  

E-print Network

intento por recrear teatralmente las peripecias del narco-tráfico en Colombia con Golpe de suerte, es indudable que el conjunto dramático La Candelaria ha aprendido de sus fracasos para sorprendernos con el montaje de una obra que, en consenso de los...

Má rceles Daconte, Eduardo

1982-10-01

351

Efecto del Programa de Entrenamiento “Manejo del Dolor” en la Documentación de Enfermería en el Expediente Electrónico  

PubMed Central

Resumen En el presente trabajo se muestra la importancia de entrenar al personal de enfermería para mejorar la documentación en el expediente electrónico. Se eligió el manejo del dolor por ser un área prioritaria; una alta proporción de pacientes en período post operatorio cursa con dolor, por lo tanto, la documentación debe ser útil para la toma de decisiones clínicas. Se implementó un programa de entrenamiento denominado “Manejo del Dolor” dirigido al personal de enfermería. Se utilizó la tecnología de la información como herramienta para fortalecer el conocimiento con base en la revisión sistemática de la literatura; el personal de enfermería participante seleccionó la mejor evidencia; posteriormente se trabajó en la transferencia de este conocimiento a la práctica a través del diseño de un protocolo para el manejo del dolor. Se concluye que el conocimiento del manejo del dolor es fundamental para que enfermería documente con mayor precisión sus intervenciones. PMID:24199106

Monsiváis, María Guadalupe Moreno; Guzmán, Ma. Guadalupe Interial; Flores, Paz Francisco Sauceda; Arreola, Leticia Vázquez

2012-01-01

352

El presidente Obama anuncia nombramiento del doctor Harold Varmus  

Cancer.gov

En los últimos cinco años como director del NCI, y en otras funciones ejercidas durante muchos años, he disfrutado ampliamente cada oportunidad que he tenido de visitar los laboratorios y las oficinas, desde Bethesda hasta Frederick, para conocer en persona a los miembros del personal y compartir mis opiniones sobre temas importantes en torno a la ciencia y al manejo de este gran Instituto.

353

Decoding F508del Misfolding in Cystic Fibrosis  

PubMed Central

The functional deficiency of the cystic fibrosis transmembrane conductance regulator (CFTR), a plasma membrane chloride channel, leads to the development of cystic fibrosis. The deletion of a phenylalanine at residue 508 (F508del) is the most common cause of CFTR misfolding leading to the disease. The F508del misfolding originates in the first nucleotide-binding domain (NBD1), which induces a global conformational change in CFTR through NBD1’s interactions with other domains. Such global misfolding produces a mutant chloride channel that is impaired in exocytic trafficking, peripheral stability, and channel gating. The nature and atomic details of F508del misfolding have been subject to extensive research during the past decade. Current data support a central role for NBD1 in F508del misfolding and rescue. Many cis-acting NBD1 second-site mutations rescue F508del misfolding in the context of full-length CFTR. While some of these mutations appear to specifically counteract the F508del-induced misfolding, others release certain inherent conformational constraints of the human wild-type CFTR. Several small-molecule correctors were recently found to act on key interdomain interfaces of F508del CFTR. Potential rational approaches have been proposed in an attempt to develop highly effective small molecule modulators that improve the cell surface functional expression of F508del CFTR. PMID:24970227

Wang, Xiaodong Robert; Li, Chenglong

2014-01-01

354

Paso del Norte Watershed Council Coordinated Water Resources Database Project  

E-print Network

cooperative database project that would provide streamlined access to a range of water resource data in the Paso del Norte region. In August of 2002, the El Paso Water Utilities provided initial funding to the Paso del Norte Watershed Council to develop a...

Brown, Christopher; Sheng, Zhuping; Rich, Matt

355

Hoja informativa sobre la calidad del aire interior  

E-print Network

· Moho · Polen · Caspa del pelo de los animales · Humo secundario del tabaco · Formaldehído · Monóxido de deshumidificador para ayudar a controlar el moho. · Limpie para eliminar el polvo y el pelo de los animales

356

ATTIVIT SPORTIVE DEL POLITECNICO 2 Trofeo dei Poli regionali  

E-print Network

Leonardo, la parigina Eleonore Delattre studentessa Erasmus di Design, Marco Ferrario di Architettura della 36a Course Croisiere Edhec nella rada di Brest. Ecco i partecipanti, tutti del Politecnico: Marco Lecco fra la rappresentativa del Polo di Como (in blu) e Leonardo, poi vincitore con i `Biggols'. Altre

357

Pastoral del Nino: Bringing the Abundant Life to Paraguayan Children  

ERIC Educational Resources Information Center

Pastoral del Nino is transforming children's lives in rural Paraguay. Part of Pastoral Social (Catholic Social Services), Pastoral del Nino's primary focus is to bring "vida en abundancia" (the abundant life) to families by ensuring that mothers survive childbirth and children reach their first birthdays. In addition, the organization promotes…

Austin, Ann Berghout; Aquino, Cyle; Burro, Elizabeth

2007-01-01

358

Entornos generosos para el crimen: Analisis del narcotrafico en Colombia  

Microsoft Academic Search

El objetivo de este trabajo es explicar el éxito de la industria de las drogas ilegales en Colombia mediante el concepto de «generosidad del entorno». La industria de las drogas ilegales en Colombia se puede considerar exitosa porque los narcotraficantes colombianos han: (i) movilizado altas cantidades de cocaína alrededor del mundo, (ii) generado altos niveles de recursos financieros y (iii)

Isaac Beltrán y Eduardo Salcedo-Albarán; Isaac Beltrán; Eduardo Salcedo-Albarán

2007-01-01

359

Luchando infructuosamente contra la hidra: un modelo sencillo del narcotráfico  

Microsoft Academic Search

En este artículo se presenta un modelo sencillo del narcotráfico que incorpora los riesgos de esta actividad. El modelo contribuye a explicar dos características notables del narcotráfico: la generación de ganancias extraordinarias y la gran capacidad de reproducción en condiciones de prohibición y represión. El modelo genera una relación directa entre la represión a la oferta –la estrategia dominante de

2002-01-01

360

I CONGRESO INTERNACIONAL DEL AGUA .... por la vida  

E-print Network

I CONGRESO INTERNACIONAL DEL AGUA .... por la vida Jueves 09 y viernes 10 de junio de 2005/Ciudad. Temática: Riesgos y agua. Hacia una redefinición del riesgo para una mejor gestión social. Julien Rebotier (IHEAL), Paris 3 ­ Sorbonne Nouvelle. Los riesgos socionaturales y el agua, un enfoque renovado para una

Paris-Sud XI, Université de

361

Los Derechos de los Pacientes del Centro Clnico  

E-print Network

Los Derechos de los Pacientes del Centro Clínico Los Derechos de los Pacientes del Centro Clínico medir las respuestas de los pacientes al tratamiento. Existen procesos que protegen los derechos de paciente que se observen los derechos fundamentales de la dignidad humana. Esta Declaración de Derechos

362

Molecular basis of DEL phenotype in the Chinese population  

PubMed Central

Background Rh blood group system is the most complex and immunogenetic blood group system. Prevalent RHD alleles vary in different populations. We conducted the present study to examine the genotype of DEL individuals and to elucidate whether novel alleles exist in the Chinese population. Methods DEL phenotype was identified by a serologic adsorption-elution method. The nucleotide sequences of ten RHD exons and exon-intron boundary regions were evaluated by RHD gene-specific PCR-SSP and sequencing. Results Of 42306 samples from individual donors and patients, 165 samples were typed as D-negative. Among these D-negative samples, 41 DEL individuals were observed. Thirty-seven DELs were confirmed to have the RHD1227A allele. Two DELs seemed to have RHD-CE-D hybrid alleles, including one RHD-CE (4–7)-D and one RHD-CE (2–5)-D. Two novel RHD alleles were found among the rest of the DEL samples, including one RHD93T?>?A and one RHD838G?>?A. Conclusion In this study, about 24.85% (41/165) of the apparent D-negative Chinese individuals were DEL. RHD1227G?>?A is the most frequent allele in Chinese DEL phenotypes, accounting for 90.24% (37/41). The RHD-CE-D hybrid allele might be the second most frequent DEL allele in the Chinese population. Our study would contribute to the understanding of the molecular mechanism underlying D antigen expression of DEL individuals and provide useful information for designing suitable genotyping strategies in RhD-negative individuals in Asia. PMID:24884404

2014-01-01

363

Publicaciones del IGME: serie Hidrogeologa y aguas subterrneas, n 14. VI Simposio del Agua en Andaluca. I: 619-628. 2005  

E-print Network

Publicaciones del IGME: serie Hidrogeología y aguas subterráneas, nº 14. VI Simposio del Agua en) , Benavente Herrera, José(2) e Hidalgo Estévez, Mª del Carmen(3) (1) CSIC e Instituto del Agua (Univ. Granada). C/ Ramón y Cajal, 4. 18071Granada. Correo electrónico: acastill@ugr.es (2) Instituto del Agua (Univ

Castillo, Antonio

364

Llamado a cubrir Beca de investigacin. Uso del agua en Sistemas de Produccin Agrcola del Chaco Semirido.  

E-print Network

Llamado a cubrir Beca de investigación. Uso del agua en Sistemas de Producción Agrícola del Chaco agua en sistemas de producción agrícola en el Chaco Semiárido mediante modelos funcionales de cultivo

Nacional de San Luis, Universidad

365

Declaración del Instituto Nacional del Cáncer sobre la aprobación de la vacuna de VPH por la FDA  

Cancer.gov

Hace casi dos décadas que los investigadores del NCI y de otras instituciones comenzaron a investigar las causas fundamentales del cáncer cervical. Esta búsqueda científica resultó en la aprobación de hoy de la vacuna GardasilTM por la Food and Drug Administration.

366

[La Medicina del Lavoro: 100 volumes].  

PubMed

With these pages La Medicina del Lavoro starts its 100th volume, so we have yet another historical occasion to celebrate the oldest occupational health journal in the world that is still publishing. Over the last few years we have had many occasions to celebrate, for example several anniversaries of the Journal (the 80th volume in 1989, 90 years in 1992, 100 years in 2001); the centenary of the foundation of the Clinica del Lavoro "Luigi Devoto" of Milan in 2001; the celebration of the 300 years' anniversary of the publication of De Morbis Artificum Diatriba by Bernardino Ramazzini, and we obviously hope to continue for many years to come in this positive outlook. One hundred volumes makes for a very large collection, with the highs and lows ofthe Journal's history (here we mean the variations in number of pages and physical size of the Journal). It is thanks to the Editors-in-chief(there have been very few so we can cite them all: Luigi Devoto, 1901-1936; Luigi Preti, 1936-1941; Enrico Vigliani, 1943-1992; e Vito Foà, 1992 to the present); the contributors who in various ways and with varying degrees of commitment but always with an exceptional personal participation, that it has been possible to reach 100 volumes, starting with C. Moreschi who, along with Luigi Devoto, was the first and sole editor at the Journal's foundation; up to the present extended and impressive editorial board; the printers (from the first. Tipografia Cooperativa, Via dei Molini in Pavia, to the latest: Casa Editrice Mattioli in Fidenza); the sponsors, including the most evident who, via advertising (rather limited as a matter offact), directly gave information about themselves, but also those who have often been or are behind the scenes, ensuring fundamental support which is not visible; content. articles, news, events, reports, ideas, opinions, photographs, tables, numbers... etc, which are really impossible to sum up. But the true collection which, for obvious reasons, cannot be individually named, consists of the people and the ideas that have enriched the history of the Journal in its over 100 years of existence. And the subscribers, above all, who by their almost anonymous presence have been the true guarantors of the Journal's ife. And of course the contributors who with their articles have consigned a part of their lives to history. Starting from 1925 we counted nearly 11.000, a really grand number. It would be wonderful if we could invite them all to a hypothetical (and impossible) grand convention to simply say "Thank you, your contributions will not be forgotten". There have been 100 volumes but in actual fact the Journal is more than 100 years old. It was founded in Pavia in 1901 as Il Lavoro-Rivista di fisiologia, clinica ed igiene del lavoro, and between 1901 and 1910 only three volumes were published, then, due to the difficulties during the First World War and the immediate post-war years, there were no issues in 1916, 1918 and 1919. Issues finally became regular in 1920 with volume 11; from that moment on not one issue was missed and the Journal even got through the Second World War without interruptions. In 1925, with volume 16, it took on the name that still distinguishes it to-day: La Medicina del Lavoro, "the official standard bearer of a work of enormous scientific, social and political content" as Luigi Devoto presented the event at the time. The first few years of the Journal were difficult ones (with only three volumes published in 10 years) to the effect that events such as the First International Congress on Occupational Diseases (Milano, 1906), the foundation of the International Commission for Occupational Health (1906), the First National Italian Congress on Occupational Diseases (Palermo, 1907), and above all the inauguration of the Clinica del Lavoro in Milano (20 March, 1910) are not reported in the Journal, which by 1911 had resumed publication but had moved to Milan. Many years have passed since those first three volumes and in the meantime we have moved on to another century and

Zocchetti, C

2009-01-01

367

Wide Air Gap and Large-Scale Bearingless Segment Motor With Six Stator Elements  

Microsoft Academic Search

In recent years, the demand for high purity spinning processes has been growing in certain industry branches, such as the semiconductor, biotechnological, pharmaceutical, and chemical industry. Therefore, the cleanness specifications have been tightened, and hermetically sealed process chambers are preferred. This paper presents an advantageous solution for such an application featuring a large scale, wide air gap, and a high

W. Gruber; T. Nussbaumer; H. Grabner; W. Amrhein

2010-01-01

368

Stator structure for supporting an outer air seal in a gas turbine engine  

Microsoft Academic Search

This patent describes an axial flow gas turbine engine of the type having an axis of rotation A, an annular flow path for working medium gases, a coolable outer case which extends circumferentially about the working medium flow path and a turbine section through which the working medium gases are passed. The turbine section includes an array of rotor blades

Laurello

1987-01-01

369

Can the standard stator bar condition assessment tests be replaced by reflectance spectroscopy?  

Microsoft Academic Search

Condition assessment is an imperative for effective power system asset management and there is a pressing need to rapidly acquire data on the operational performance of high voltage solid and liquid electrical insulation systems, both during the manufacturing process as well as in the field. These systems are governed by a number of manufacturing, operational and environmental variables which affect

Douglas Conley; James Han; Henryk Herman; Gary C Stevens

2010-01-01

370

Torque ripple reduction of axial flux permanent magnet synchronous machine with segmented and laminated stator  

Microsoft Academic Search

Torque ripple is the parasitic element that causes mechanical vibration, acoustic noise and even latent operational failure in permanent magnet (PM) machines. Consequently, considerable design efforts should be made to minimize torque ripple of the machines for high performance applications. In this paper, one cost effective torque ripple reduction technique is proposed and investigated for an axial flux permanent magnet

W. Fei; P. C. K. Luk

2009-01-01

371

System and method for bearing fault detection using stator current noise cancellation  

DOEpatents

A system and method for detecting incipient mechanical motor faults by way of current noise cancellation is disclosed. The system includes a controller configured to detect indicia of incipient mechanical motor faults. The controller further includes a processor programmed to receive a baseline set of current data from an operating motor and define a noise component in the baseline set of current data. The processor is also programmed to repeatedly receive real-time operating current data from the operating motor and remove the noise component from the operating current data in real-time to isolate any fault components present in the operating current data. The processor is then programmed to generate a fault index for the operating current data based on any isolated fault components.

Zhou, Wei (Los Angeles, CA); Lu, Bin (Kenosha, WI); Habetler, Thomas G. (Snellville, GA); Harley, Ronald G. (Lawrenceville, GA); Theisen, Peter J. (West Bend, WI)

2010-08-17

372

System and method for motor fault detection using stator current noise cancellation  

DOEpatents

A system and method for detecting incipient mechanical motor faults by way of current noise cancellation is disclosed. The system includes a controller configured to detect indicia of incipient mechanical motor faults. The controller further includes a processor programmed to receive a baseline set of current data from an operating motor and define a noise component in the baseline set of current data. The processor is also programmed to acquire at least on additional set of real-time operating current data from the motor during operation, redefine the noise component present in each additional set of real-time operating current data, and remove the noise component from the operating current data in real-time to isolate any fault components present in the operating current data. The processor is then programmed to generate a fault index for the operating current data based on any isolated fault components.

Zhou, Wei (Los Angeles, CA); Lu, Bin (Kenosha, WI); Nowak, Michael P. (Menomonee Falls, WI); Dimino, Steven A. (Wauwatosa, WI)

2010-12-07

373

STATOR-ROTOR AEROELASTIC INTERACTION FOR THE TURBINE LAST STAGE IN 3D TRANSONIC FLOW  

Microsoft Academic Search

A three-dimensional numerical analysis for aerodynamic unsteady forces and flutter parameters of the last stage steam turbine\\u000a 13K215 rotor blades have been presented. The low frequency excitation was simulated for a 94 rotating blades with 54 nozzles.\\u000a It was assumed that the pressure behind the rotor blades is changing in the circumferential direction. The flutter parameters\\u000a of this stage were

Romuald Rzadkowski; Vitaly Gnesin; Luba Kolodyazhnaya

374

Leaf seal for gas turbine stator shrouds and a nozzle band  

DOEpatents

A leaf seal assembly is secured to the trailing edge of a shroud segment for sealing between the shroud segment and the leading edge side wall of a nozzle outer band. The leaf seal includes a circumferentially elongated seal plate biased by a pair of spring clips disposed in a groove along the trailing edge of the shroud segment to maintain the seal plate in engagement with the flange on the leading edge side wall of the nozzle outer band. The leaf seal plate and spring clips receive pins tack-welded to the shroud segment to secure the leaf seal assembly in place.

Burdgick, Steven Sebastian (Schenectady, NY); Sexton, Brendan Francis (Simpsonville, SC)

2002-01-01

375

Numerical simulation of sand erosion phenomena in rotor\\/stator interaction of compressor  

Microsoft Academic Search

Sand erosion is a phenomenon where solid particles impinging to a wall cause serious mechanical damages to the wall surface.\\u000a This phenomenon is a typical gas-particle two-phase turbulent flow and a multi-physics problem where the flow field, particle\\u000a trajectory and wall deformation interact with each other. On the other hand, aircraft engines operating in a particulate environment\\u000a are subjected to

Masaya Suzuki; Kazuaki Inaba; Makoto Yamamoto

2008-01-01

376

Aerodynamics of a Transitioning Turbine Stator Over a Range of Reynolds Numbers  

NASA Technical Reports Server (NTRS)

Midspan aerodynamic measurements for a three vane-four passage linear turbine vane cascade are given. The vane axial chord was 4.45 cm. Surface pressures and loss coefficients were measured at exit Mach numbers of 0.3, 0.7, and 0.9. Reynolds number was varied by a factor of six at the two highest Mach numbers, and by a factor of ten at the lowest Mach number. Measurements were made with and without a turbulence grid. Inlet turbulence intensities were less than I% and greater than IO%. Length scales were also measured. Pressurized air fed the test section, and exited to a low pressure exhaust system. Maximum inlet pressure was two atmospheres. The minimum inlet pressure for an exit Mach number of 0.9 was one-third of an atmosphere, and at a Mach number of 0.3, the minimum pressure was half this value. The purpose of the test was to provide data for verification of turbine vane aerodynamic analyses, especially at low Reynolds numbers. Predictions obtained using a Navier-Stokes analysis with an algebraic turbulence model are also given.

Boyle, R. J.; Lucci, B. L.; Verhoff, V. G.; Camperchioli, W. P.; La, H.

1998-01-01

377

High freestream turbulence studies on a scaled-up stator vane  

NASA Astrophysics Data System (ADS)

Today's gas turbine engines are operating at combustor exit temperatures far exceeding the maximum temperatures of the component alloys downstream of the combustor. These higher temperatures are necessary to increase the efficiency of the engine, and, as such, durability of the downstream components becomes an issue. The highly turbulent flowfield that exists at the exit of the combustor complicates issues further by increasing heat transfer from the hot gas to the component surface. To account for the high heat transfer rates, and provide a better prediction of the applied heat loads, detailed heat transfer and flowfield information is needed at turbulence levels representative those exiting a combustor. Flowfield measurements at high freestream turbulence levels indicated that turbulence, which was isotropic at the inlet, became highly anisotropic in the test section as a result of surface curvature and strain. Turbulent kinetic energy levels were shown to increase in the passage by as much as 131% and 31% for the 10% and 19.5% turbulence levels. Although the turbulent kinetic energy was high, the turbulence level based upon local velocity decreased quickly to levels of 3% and 6% near the suction surface for the 10% and 19.5% turbulence levels. For the pressure surface, local turbulence levels were as high as 10% and 16% for the 10% and 19.5% turbulence levels. High local turbulence levels and heat transfer augmentation were observed near the stagnation location, by as much as 50%, and along the pressure surface, by as much as 80%, where airfoil geometries have shown degradation after prolonged usage. Endwall flowfield measurements on a plane at the stagnation location showed that a horseshoe vortex developed in the juncture region of the vane at high freestream. turbulence similar to that at low freestream turbulence. Measurements near the center of the vortex indicated that the vortex was highly unsteady. In regions where strong secondary flows (horseshoe and passage vortex) were present, these vortices dominated the heat transfer and the augmentations due to high freestream turbulence were small.

Radomsky, Roger William, Jr.

2000-10-01

378

Flowfield measurements for a highly turbulent flow in a stator vane passage  

SciTech Connect

Turbine vanes experience high convective surface heat transfer as a consequence of the turbulent flow exiting the combustor. Before improvements to vane heat transfer predictions through boundary layer calculations can be made, an understanding of how the turbulent flow in the inviscid region of the passage reacts as it passes between two adjacent turbine vanes is needed. In this study, a scaled-up turbine vane geometry was used in a low-speed wind tunnel simulation. The test section included a central airfoil with two adjacent vanes. To generate the 20% turbulence levels at the entrance to the cascade, which simulates levels exiting the combustor, an active grid was used. Three-component laser-Doppler velocimeter measurements of the mean and fluctuating quantities were measured in a plane at the vane midspan. Coincident velocity measurements were made to quantify Reynolds shear stress and correlation coefficients. The energy spectra and length scales were also measured to give a complete set of inlet boundary conditions that can be used for numerical simulations. The results show that the turbulent kinetic energy throughout the inviscid region remained relatively high. The surface heat transfer measurements indicated high augmentation near the leading edge as well as the pressure side of the vane as a result of the elevated turbulence levels.

Radomsky, R.W.; Thole, K.A.

2000-04-01

379

Active Noise Control of Low Speed Fan Rotor-Stator Modes  

NASA Technical Reports Server (NTRS)

This report describes the Active Noise Cancellation System designed by General Electric and tested in the NASA Lewis Research Center's 48 inch Active Noise Control Fan. The goal of this study was to assess the feasibility of using wall mounted secondary acoustic sources and sensors within the duct of a high bypass turbofan aircraft engine for active noise cancellation of fan tones. The control system is based on a modal control approach. A known acoustic mode propagating in the fan duct is cancelled using an array of flush-mounted compact sound sources. Controller inputs are signals from a shaft encoder and a microphone array which senses the residual acoustic mode in the duct. The canceling modal signal is generated by a modal controller. The key results are that the (6,0) mode was completely eliminated at 920 Hz and substantially reduced elsewhere. The total tone power was reduced 9.4 dB. Farfield 2BPF SPL reductions of 13 dB were obtained. The (4,0) and (4,1) modes were reduced simultaneously yielding a 15 dB modal PWL decrease. Global attenuation of PWL was obtained using an actuator and sensor system totally contained within the duct.

Sutliff, Daniel L.; Hu, Ziqiang; Pla, Frederic G.; Heidelberg, Laurence J.

1996-01-01

380

Induction Machine Bearing Failures Detection Using Stator Current Frequency Spectral Subtraction  

E-print Network

, fault detection, signal pro- cessing, spectral subtraction. NOMENCLATURE [.] 1 Matrix inverse the induction machine is very reliable, many failures can occur such as bearing faults, air-gap eccentricity breakdowns. The purpose of this paper is to propose a new approach for fault detection based on the spectral

Boyer, Edmond

381

Blade-forced vibration effects in turbomachinery rotor-stator interaction  

E-print Network

the unsteady flow in a turbine. Results are presented for non-dimensional pressure, velocity, and entropy in the blade passage. The two-stage turbine flow analysis was completed for the case with blade-forced response as well as the case without blade...

Collard, Joseph Eugene

2012-06-07

382

Prediction of the aerodynamic environment and heat transfer for rotor-stator configurations  

NASA Astrophysics Data System (ADS)

A numerical study of the aerodynamic and thermal environment associated with axial turbine stages is presented. Computations were performed using a modification of the unsteady viscous code, ROTORI, and an improved version of the steady inviscid cascade system, MERIDL-TSONIC, coupled with boundary layer codes, BLAYER and STAN5. Two different turbine stages were analyzed: the first stage of the United Technologies Research Center Large Scale Rotating Rig (LSRR) and the first stage of the Space Shuttle Main Engine (SSME) high pressure fuel turbopump turbine. The time-averaged airfoil midspan pressure and heat transfer profiles were predicted for numerous thermal boundary conditions including adiabatic wall, prescribed surface temperature, and prescribed heat flux. Computed solutions are compared with each other and with experimental data in the case of the LSRR calculations. Modified ROTORI predictions of unsteady pressure envelopes and instantaneous contour plots are also presented. Relative merits of the two computational approaches are discussed.

Griffin, L. W.; McConnaughey, H. V.

1989-06-01

383

Crystal structure of yeast V-ATPase subunit C reveals its stator function  

E-print Network

and Biotechnology, The George S Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv, Israel Vacuolar Hþ the central helical coiled-coil g-subunit (Abra- hams et al, 1994). The structure strongly supported

Nelson, Nathan

384

Loss Calculation of Induction Motors Considering Harmonic Electromagnetic Fields in Stator and Rotor  

NASA Astrophysics Data System (ADS)

A method of loss calculation for induction motors is proposed. The combined 3D-2D time stepping finite element analysis is carried out to obtain the copper loss and the time-variation of the magnetic field in the motor. The iron loss is calculated approximately considering the time-variation of the magnetic field direction and the minor hysteresis loops caused by the time-harmonic fields using practical computer resources. The proposed method is applied to 4 types of induction motors, which are the solid rotor induction motors with/without slot and the cage induction motors with/without skew. The measured and the calculated total losses and the iron losses agree well in all cases. The differences of the loss distributions of each motor are also compared and investigated.

Yamazaki, Katsumi

385

Reacting Mixing-Layer Computations in a Simulated Turbine-Stator Passage  

E-print Network

the flow, it is possible to add heat without increasing the flow temperature beyond the turbine-blade burning fuel in the turbine stages. For the ground-based gas turbine, improvement has been found in power the turbine passage offer an opportunity for a major technological improvement. The gas turbine engine

Liu, Feng

386

Optimization of Stator Design in a Consequent-Pole Type Bearingless Motor Considering Magnetic Suspension Characteristics  

Microsoft Academic Search

In this paper, a design optimization method for a consequent-pole bearingless motor is presented. This produces stable magnetic suspension under motor torque generation. The suspension force reduction and direction error, which can be caused by torque generation, are limited in the proposed designs. In the optimization routine, the number of suspension and torque winding turns and air-gap length are carefully

Masakazu Nakagawa; Yoshikazu Asano; Akira Mizuguchi; Akira Chiba; Che Xiao Xuan; M. Ooshima; M. Takemoto; T. Fukao; O. Ichikawa; D. G. Dorrell

2006-01-01

387

Bearingless Segment Motor With Five Stator Elements—Design and Optimization  

Microsoft Academic Search

Bearingless motors and active magnetic bearings work completely contactless and wearless. With these properties, hermetically sealed and lubricant-free rotating systems for various applications can be designed. It is possible to stabilize three degrees of freedom by reluctance forces when a permanent-magnet excited rotor disc is used. Hence, only the remaining three degrees of freedom are actively controlled. A subtype of

Wolfgang Gruber; Wolfgang Amrhein; Michael Haslmayr

2009-01-01

388

Disk-laser welding of Hastelloy X cover on René 80 turbine stator blade  

NASA Astrophysics Data System (ADS)

Nickel-base alloys, such as Hastelloy X and René 80, are among the most common ones for aerospace applications, due to their mechanical strength at high temperatures and oxidation resistance properties, although processing for missile and space vehicle applications requires extensive fusion and resistance welding for fastening. Laser welding using a Yb:YAG disk laser in continuous mode emission is investigated in this paper for overlap joining of Hastelloy X plates on René 80 samples resulting from waste turbine blades. An explorative study is carried out in order to find an appropriate processing window as well as discussing bead features and common issues. Special fixtures for clamping have been specifically developed and tested. A 3-factors study with power, welding speed and focus position as governing parameters has been arranged; 2 levels have been chosen for each factor. Geometric features, defects and indications are discussed referring to the parameters main effects.

Caiazzo, Fabrizia; Corrado, Gaetano; Alfieri, Vittorio; Sergi, Vincenzo; Cuccaro, Luigi

2012-01-01

389

Rotor wake characteristics relevant to rotor-stator interaction noise generation  

NASA Technical Reports Server (NTRS)

Mean and turbulent wake properties at three axial locations behind the rotor of an aerodynamically loaded 1.2 pressure ratio fan were measured using a stationary cross film anemometer in an anechoic wind tunnel. Wake characteristics at four radial immersions across the duct at four different fan speeds were determined utilizing a signal enhancement technique. The shapes of the waveforms of the mean rotor relative and mean upwash velocities were shown to change significantly across the span of the blades. In addition, an increase in fan rotational speed caused an increase in the maximum wake turbulence intensity levels near the hub and tip. Spectral analysis was used to described the complex nature of the rotor wake.

Shaw, L. M.; Balombin, J. R.

1981-01-01

390

Quantification of flagellar motor stator dynamics through in vivo proton-motive force control  

E-print Network

Murray J. Tipping,1 Bradley C. Steel,2 Nicolas J. Delalez,2 Richard M. Berry2 and Judith P. Armitage1 * 1 to rotary motion by changes in electrostatic interactions between MotAand the rotor protein FliG (Zhou et al

Berry, Richard

391

Preliminary design and viability consideration of external, shroud-based stators in wind turbine generators  

E-print Network

Horizontal-axis wind turbine designs often included gearboxes or large direct-drive generators to compensate for the low peripheral speeds of the turbine hub. To take advantage of high blade tip speeds, an alternative ...

Shoemaker-Trejo, Nathaniel (Nathaniel Joseph)

2012-01-01

392

Source localization for active control of turbofan rotor-stator broadband noise  

Microsoft Academic Search

In order to identify a reference signal source for an active noise cancellation system, cross-correlation techniques were used to localize broadband noise source regions on exit guide vanes of the NASA Glenn Research Center Advance Noise Control Fan (ANCF). Arrays of surface pressure sensors were imbedded in one guide vane and in the wall of the fan. Synchronous sampling was

Bruce E. Walker

2005-01-01

393

Source localization for active control of turbofan rotor-stator broadband noise  

NASA Astrophysics Data System (ADS)

In order to identify a reference signal source for an active noise cancellation system, cross-correlation techniques were used to localize broadband noise source regions on exit guide vanes of the NASA Glenn Research Center Advance Noise Control Fan (ANCF). Arrays of surface pressure sensors were imbedded in one guide vane and in the wall of the fan. Synchronous sampling was used with a multichannel data acquisition system to allow removal of periodic components from the signals. The signals were then cross-correlated to assess radiation directivity and the relationship between vane surface pressure and in-duct acoustic noise. The results of these measurements indicated that broadband unsteady pressures near the leading edge tip of the guide vane were well enough correlated with acoustic radiation that 2-3 dB active noise cancellation could be achieved using a simple gain-delay control algorithm and actuator array. After successful simulation in a wind tunnel environment the concept was incorporated on 15 guide vanes and tested in ANCF. Cross-correlation measurements were further used to evaluate system performance and to identify competing noises from rotating and stationary sources within the fan.

Walker, Bruce E.

2005-09-01

394

A Novel Stator Winding Capacitance Dividing Method for the Generator with Considerable Winding Distributed Capacitance  

Microsoft Academic Search

This paper presents a method which can equivalently arrange the capacitance distribution along with the winding of the generator on the terminal and neutral respectively in a reasonable partition, particularly for a type of high-voltage graded insulated cable wound generator, Powerformer. This method can be used to compensate the capacitive current wholly to improve the reliability of the differential protection.

Yonghong Tao; Qing Tian; Xiangning Lin

2007-01-01

395

Los discursos del miedo en la prensa uruguaya  

Microsoft Academic Search

A fines de julio de 2002 el Uruguay sufre una de sus peores crisis financieras, económicas y sociales. Reprogramaciones de las cuentas bancarias, tanto de instituciones privadas como del Estado, supuestos saqueos por \\

María Ángela Giaimo

396

La Revolucin del Shale Gas Profesor: Hugh Rudnick  

E-print Network

La Revolución del Shale Gas Mayo 2011 Profesor: Hugh Rudnick Profesional Externo: Verónica Cortés........................................................................................................................................ 6 ¿Qué es el Shale Gas...................................................................................................................................... 7 Shale Gas

Rudnick, Hugh

397

Servei d'Activitats Culturals Normativa interna del SAC  

E-print Network

Servei d'Activitats Culturals Normativa interna del SAC Formaci� 1. Lloc, dates i horaris Els� altres criteris, si ho considera oport�. 5. Anul�laci� d'un curs El SAC es reserva la possibilitat de

Oro, Daniel

398

Living Legacy: A Conversation with Carolina Gomez del Valle.  

ERIC Educational Resources Information Center

Carolina Gomez del Valle has been involved in training other Montessorians in Mexico, Chile, Nicaragua, Peru, and Taiwan. This interview explores her experiences with Montessori education and describes how she has woven her religious training and Montessori philosophy together. (PAM)

Montessori Life, 1993

1993-01-01

399

ESTRUCTURAS ALGEBRAICAS Nombre del profesor: Jos F. Fernando Galvn  

E-print Network

ESTRUCTURAS ALGEBRAICAS Grupos A Nombre del profesor: Jos� F. Fernando Galv�n Tutor�as: ser�n en el estructura. Factores invariantes y divisores elementales. El grupo de las unidades de un cuerpo finito

Fernando, Jose F.

400

ARTICLEINPRESS Seismic stratigraphy of Lago Fagnano sediments (Tierra del Fuego,  

E-print Network

S in the heart of the Island of Tierra del Fuego, Lago Fagnano occupies the deepest of a chain of en strong tectonic pulses along the MFT system. Gravity cores show a regular alternation of light and dark

Gilli, Adrian

401

FRAGOMEN, DEL REY, BERNSEN & LOEWY, LLP US IMMIGRATION CLIENT ALERT  

E-print Network

FRAGOMEN, DEL REY, BERNSEN & LOEWY, LLP US IMMIGRATION CLIENT ALERT If you have any questions about to the United States. This Client Alert provides general guidance on procedures, including visa issuance at U

Scharer, John E.

402

El metabolismo social del País Vasco desde el análisis de flujos materiales  

Microsoft Academic Search

La desvinculación de la mejora del bienestar respecto del uso de los recursos y de la contaminación es esencial para lograr un desarrollo sostenible. Para avanzar en esta dirección es preciso partir del conocimiento del metabolismo de la sociedad. Es decir, debemos analizar en qué medida nuestras sociedades “ingieren” materias primas, que son “metabolizadas” para producir bienes y servicios, y

Iñaki Arto

2009-01-01

403

Comunicacionas mansualas dal Instituto Intllrnacional de la Potase, Berna (Suiza) Ciencia del Suelo  

E-print Network

del Suelo 728 continuacion N° 5/1981 La quimica del potasio en suelos arenosos* (On the chemistry of potassium in sandy soils) D, L. Sparks Profesor Auxiliar de Qulmica Fisica del Suelo, Departamento de y nativo en suelos Dothan. Sparks D.L., Zelazny L. W., Martens D. C.: Cineticas del Intercambio de

Sparks, Donald L.

404

Lecciones del programa de prevención temprana de la violencia, Medellín, Colombia  

Microsoft Academic Search

Se describen las características y evolución del Programa de Prevención Temprana de la Agresión del Municipio de Medellin, Colombia, que, al parecer, es la más amplia experiencia de su género en Latinoamérica. Se realiza la primera evaluación del impacto atribuible a este programa, focalizada en su etapa inicial. El análisis antes \\/ después reporta varios efectos positivos del Programa. Conclusión

Luis Fernando Duque; José Fernando Orduz; Juan de Jesús Sandoval; Beatriz Elena Caicedo; Joanne Klevens

2007-01-01

405

Evoluzione della vegetazione nei pressi del Lago di Lavarone (TN) negli ultimi 2200 anni  

Microsoft Academic Search

RIASSUNTO - Evoluzione della vegetazione nei pressi del Lago di Lavarone (TN) negli ultimi 2200 anni - Lo studio pollinico e paleolimnologico della sequenza S5 proveniente dal Lago di Lavarone, condotto nel corso del progetto OLOAMBIENT, ha permesso di ottenere un quadro dettagliato sull'evoluzione del territorio nei pressi del lago negli ultimi 2200 anni. Sulla base delle informazioni archeologiche e

Enrico ARPENTI; Maria Letizia FILIPPI

406

PUEDE EXPLICARSE EL PRECIO EXTERNO DEL CAFÉ CON UN MODELO ECONOMETRICO NO LINEAL?  

Microsoft Academic Search

El precio internacional del café, como el de la mayoría de los productos primarios se ha caracterizado por la inestabilidad y las grandes fluctuaciones. La formación del precio del café verde es un proceso complejo que depende de una multiplicidad de variables, como la calidad y disponibilidad del producto, el lugar de origen, el sitio de compra, las expectativas de

Franz Alonso Hamann S

1996-01-01

407

Gli approcci terapeutici al trattamento del dolore cronico  

Microsoft Academic Search

\\u000a La terapia del paziente con dolore cronico inizia molto prima dell’incontro con il clinico, poiché tutto ciò che ha preceduto\\u000a il primo appuntamento, in un lasso di tempo talvolta molto lungo, ha portato il paziente a una parziale presa di coscienza\\u000a ed elaborazione del proprio disagio (Ercolani 1997). Presentandosi dal clinico, il paziente tende il più delle volte a sottovalutare

Gianluca Castelnuovo; Mauro Ercolani; Mario Tavola; Daniele Rovaris; Lara Bellardita; Paola Cuzziol; Enrico Molinari

408

Aportació a coneixement florístic del Moianès (Catalunya central)  

Microsoft Academic Search

Seguint en la línia d'ampliació del coneixement florístic de l'àrea del Moianès, presentem dades d'interès corològic de 46 tàxons. Es tracta bàsicament d'espècies d'ambients forestals i pradencs, bona part no citades d'aquest sector i algunes de molt rares o inexistents al territori ausosegàrric. Hi ha un primer grup d'espècies, que a les terres catalanes són bàsicament pirinenques [Linum viscosum L.,

Arnau Mercadé López

2007-01-01

409

Student Competition: Siting Potential Dams at Camp Del Webb, Utah  

E-print Network

Siting Potential Dams at Camp Del Webb, Utah Presented By: Kyle Wamser Problem ? Camp Del Webb is Lacking an Onsite Lake ? High Adventure Bases generally need aquatics ? Large lake nearby, but transportation is required ? Possible Solution... hillshade ? Finding Possible Lake Locations ? Added three potential dam sites ? Calculated watersheds ? Extended dams through terrain to prevent runoff on the sides ? Calculated watershed dam elevation, which identified lakes Results...

Wamser, William Kyle

2007-11-14

410

Difusión de resultados iniciales del Estudio del Tamoxifeno y del Raloxifeno (STAR): el fármaco para el tratamiento de la osteoporosis, raloxifeno, es tan efectivo como el Tamoxifeno en la prevención de cáncer de seno invasor  

Cancer.gov

Los resultados iniciales del Estudio del Tamoxifeno y del Raloxifeno, STAR, demuestran que el fármaco raloxifeno, actualmente utilizado para prevenir y tratar la osteoporosis en mujeres posmenopáusicas, funciona tan bien como el tamoxifeno para reducir el riesgo de cáncer de seno entre las mujeres posmenopáusicas que tienen riesgo elevado de padecer la enfermedad. Preguntas y respuestas

411

Cirug?a de los trastornos del comportamiento: el estado del arte  

PubMed Central

Introducción: La cirugía de los trastornos del comportamiento (CTC) se está convirtiendo en un tratamiento más común desde el desarrollo de la neuromodulación. Métodos: Este artículo es una revisión no sistemática de la historia, indicaciones actuales, técnicas y blancos quirúrgicos de la CTC. Dividimos su historia en 3 eras: la primera comienza en los inicios de la psicocirugía y termina con el desarrollo de las tícnicas estereotácticas, cuando comienza la segunda era. Ésta se caracteriza por la realización de lesiones estereotácticas. Nos encontramos transitando la tercera era, que comienza cuando la estimulación cerebral profunda (ECP) comienza a ser usada en CTC. Resultados: A pesar de los errores graves cometidos en el pasado, hoy en día, la CTC está renaciendo. Los trastornos psiquiátricos que se más frecuentemente se tratan con cirugía son: depresión refractaria, trastorno obsesivo-compulsivo y síndrome de Tourette. Además, algunos pacientes con agresividad fueron tratados quirúrgicamente. Hay varios blancos estereotácticos descriptos para estos trastornos. La estimulación vagal puede ser usada también para depresión. Conclusión: Los resultados de la ECP en estos trastornos parecen alentadores. Sin embargo, se necesitan más estudios randomizados para establecer la efectividad de la CTC. Debe tenerse en cuenta que una apropiada selección de pacientes nos ayudará a realizar un procedimiento más seguro así como también a lograr mejores resultados quirúrgicos, conduciendo a la CTC a ser más aceptada por psiquiatras, pacientes y sus familias. Se necesita mayor investigación en varios temas como: fisiopatología de los trastornos del comportamiento, indicaciones de CTC y nuevos blancos quirúrgicos. PMID:25165612

Yampolsky, Claudio; Bendersky, Damian

2014-01-01

412

¿Qué es el Servicio de Información sobre el Cáncer del NCI?  

Cancer.gov

El Servicio de Información sobre el Cáncer (CIS) del Instituto Nacional del Cáncer (NCI) es un programa financiado con fondos del Gobierno Federal y fue establecido en 1975 como un componente fundamental de la misión y los programas de educación e información del cáncer del NCI. Comuníquese con nosotros para hablar con un especialista capacitado en información quien puede responder a sus preguntas relacionadas con el cáncer en inglés y español.

413

SOLICITUD DE PERMISOS PARA PUBLICAR EN LA WEB DE LA UA A la atencin del Director del Servicio de Informtica.  

E-print Network

SOLICITUD DE PERMISOS PARA PUBLICAR EN LA WEB DE LA UA A la atención del Director del Servicio de conozca): http://www.ua.es/ http://www.ua.es/ http://www.ua.es/ http://www.ua.es/ BAJA DE PERMISOS en las siguientes direcciones web (en caso de que las conozca): http://www.ua.es/ http://www.ua

Escolano, Francisco

414

V339 Del (Nova Del 2013) is a weak non-super-soft X-ray source  

NASA Astrophysics Data System (ADS)

V339 Del (Nova Del 2013) is currently being monitored approximately daily by Swift-XRT. X-ray analysis has been complicated due to optical loading caused by photons from the very bright optical source. (For a discussion of optical loading in the XRT, see our help page.) At early times, the data were collected mainly in Windowed Timing mode to mitigate this issue, and no X-ray source was detected (ATel #5283, #5305, #5318).

Page, K. L.; Beardmore, A. P.

2013-09-01

415

0.0 -8 objectius pel mil.lenni A la Cimera del Millenni, celebrada l'any 2000, el conjunt dels Estats  

E-print Network

a b 0.0 - 8 objectius pel mil.lenni A la Cimera del Mil·lenni, celebrada l'any 2000, el conjunt dels Estats membres de les Nacions Unides van aprovar la Declaració del Mil·lenni, en la qual: Van considerar com a valors fonamentals del nou mil·lenni: q La llibertat q La igualtat q La solidaritat q La

Oro, Daniel

416

Publicaciones del IGME: serie Hidrogeologa y aguas subterrneas, n 14. VI Simposio del Agua en Andaluca. II: 1.229-1.236. 2005  

E-print Network

Publicaciones del IGME: serie Hidrogeología y aguas subterráneas, nº 14. VI Simposio del Agua en Andalucía. II: 1.229-1.236. 2005 Sobre la calidad físico-química de las aguas superficiales del área metropolitana de Granada Sánchez Díaz, Luis* y Castillo Martín, Antonio** * Instituto del Agua. Universidad de

Castillo, Antonio

417

La reparación del daño como mecanismo de tutela de la persona. Del daño a la salud a los nuevos daños extrapatrimoniales  

Microsoft Academic Search

En la actualidad, el operador del Derecho se enfrenta a dos de los más importantes problemas del nuevo derecho de daños: por un lado, la clasificación del perjuicio y, por el otro, la reparación correspondiente a cada una de sus categorías, que debe estar informada por el principio de reparación integral, y que impone en consecuencia considerar más que las

Milagros Koteich Khatib

418

Ingenieros militares en España en el siglo XIX. Del arte de la guerra en general a la profesión del ingeniero en particular  

Microsoft Academic Search

Esta comunicación tiene por objeto mostrar las diferentes opciones profesionales del Cuerpo de Ingenieros Militares español durante el siglo XIX. Una corporación técnica y facultativa que desde principios del ochocientos perdió algunas competencias del campo de la ingeniería civil. En este trabajo señalaremos la adaptación de los mecanismos de selección de estos ingenieros y las reivindicaciones que realizaron para equipararse

José Ignacio Muro Morales

2007-01-01

419

Componentes naturales y de uso del suelo vulnerables a las variaciones del nivel del mar en la costa atlántica de México  

Microsoft Academic Search

Palabras clave Regionalizaci6n de costas, fislografia, vulnerabilidad costera, uso del suelo Absúact Geomorphological alaradenstia of the mastal iongitudinal prn* and the arrangwent of the physiographical stmcture allowed the rmnition of two zonas: a) the intertidai zone -a basic sntne for dired imoaci of sea leve1 dame: and b) an adjacent peritidál (supralittoral) hnge &n area of cushioning or of polential

Mano Arturo; Ortiz Pérez; Ana Patricia; Méndez Linares

420

Autores y tendencias del teatro ecuatoriano en la década de los 90  

E-print Network

teatro del absurdo, extendido entonces en Europa y México, y por otra, con el teatro "político," teatro para las masas, explícitamente orientado a su educación para el cambio social. La década de los ochenta fue de transición, la crisis del teatro... varios capítulos y dramatizados cortos, semanales. La gran mayoría de los actores han provenido del teatro, del teatro costumbrista y del café teatro de inicios de los 90. Y no ha faltado el caso de una obra con sus actores que pasaron del teatro a la...

Breilh, Alfredo

2000-10-01

421

2013 Alumni-Elected Trustees Nicole Bisagni DelToro '91, Bethesda, MD  

E-print Network

and entrepreneurship. Ms. DelToro previously served as Business Unit Manager, Romac International. Ms. Del's Council of Cornell Women; a member of the Class of 1981 Class Council and serves on the College

422

Coordinacin de la Especializacin en Ingeniera del Gas Natural Valle de Sartenejas, Universidad Simn Bolvar,  

E-print Network

DEL GAS NATURAL Grado académico que otorga Especialista en Ingeniería del Gas Natural. Perfil de emitidas por personal docente o autoridades de una Universidad de reconocido prestigio. Comprobante de pago

Vásquez, Carlos

423

La revolución keynesiana y sus pioneros: los keynesianos y la política del gobierno 1933-1939  

Microsoft Academic Search

En este artículo el autor, sobre la base de un análisis de las principales contribuciones económicas de la década del 30, destaca los elementos de Keynesianismo implícitos en los primeros aportes de Currie y en general del grupo de \\

Alan Sweezy; Traducción de Mario García

1993-01-01

424

El té y la prevención del cáncer: Solidez y límites de la evidencia científica  

Cancer.gov

Hoja informativa que resume los resultados de estudios realizados sobre el té y la prevención del cáncer. Incluye información sobre los ingredientes del té y las consideraciones de seguridad sobre el consumo de esta bebida.

425

MITOS Y VERDADES ACERCA DEL CAMBIO CLIM´ ATICO EN BOLIVIA  

Microsoft Academic Search

RESUMEN Los recientes desastres naturales han llamado la atencion de los medios de comunicacion hacia los posibles efectos del cambio climatico en Bolivia. Muchos de los desastres fueron atribuidos al calentamiento global, a El Nino o al agujero de ozono, entre otros. El presente art´õculo trata de identificar la posible relacion de los desastres naturales observados o predichos con estos

Marcos Andrade

2008-01-01

426

Las zonas mineras españolas a finales del XIX  

Microsoft Academic Search

PRESENTACIÓN Jugh James Rose, capellán de las compañías mineras inglesas, francesas y alemanas de Linares, es el autor de la obra Untrodden Spain and her black country being sketches of the life and character of the Spaniard of the interior publicada en dos volúmenes en Londres en 1875. De él sabemos que ejerció como capellán del ejército en Dover y

María Antonia López Burgos

2003-01-01

427

La Usina del Lenguaje: Teoría de la Poesía Neobarroca  

E-print Network

La usina del lenguaje: Teoría de la poesía neobarroca examines one of the most relevant poetry tendencies of the last thirty years: the Neo-baroque. In this dissertation I have endeavored to analyze the works of a number of Hispano-American poets...

De Cuba, Pablo A.

2013-08-08

428

Los determinantes sociales del pensamiento: ni anomalismo ni funcionalización  

Microsoft Academic Search

El principal objetivo del presente trabajo es indagar si las habituales tentativas por descifrar el pensamiento desde un punto de vista sociológico, a pesar de su vehemente compromiso antirreduccionista, podrían aceptar en último término la reducción de ideas, argumentos y doctrinas a sus presuntos determinantes sociales. En una primera etapa analizamos el “sociologismo anómalo” de Martin Kusch, señalamos algunas de

Josep M. Bech

2008-01-01

429

La política educativa a començaments del segle XXI  

Microsoft Academic Search

La política educativa que hay que desarrollar en España a comienzos del siglo XXI debe formar parte de las estrategias que se siguen en todas partes para mejorar los conocimientos y las competencias de toda la población y, especialmente, de las nuevas generaciones. Este trabajo repasa las enseñanzas que se derivan de los estudios internacionales como Pisa, que sirven de

M. Jesús San Segundo Gómez de Cadiñanos

2007-01-01

430

Nel quadro del complesso sforzo di risanamento della finanza  

E-print Network

e MIP, e da Harvard Business Review Italia affronterài temi descritti con la partecipazione di Risponde e conclude Antonio Mastrapasqua Presidente INPS Modera Enrico Sassoon Direttore Harvard Business Review Italia La modernizzazione della Pubblica Amministrazione per la competitività del Paese: il caso

431

Control del dolor: Apoyo para las personas con cáncer  

Cancer.gov

Contiene información sobre las medicinas contra el dolor para pacientes con cáncer, los planes para controlarlo, cómo hablar con su equipo de atención médica sobre el dolor que usted siente y qué hacer para controlar los efectos físicos y emocionales del mismo.

432

Design, aerodynamics and autonomy of the DelFly.  

PubMed

One of the major challenges in robotics is to develop a fly-like robot that can autonomously fly around in unknown environments. In this paper, we discuss the current state of the DelFly project, in which we follow a top-down approach to ever smaller and more autonomous ornithopters. The presented findings concerning the design, aerodynamics and autonomy of the DelFly illustrate some of the properties of the top-down approach, which allows the identification and resolution of issues that also play a role at smaller scales. A parametric variation of the wing stiffener layout produced a 5% more power-efficient wing. An experimental aerodynamic investigation revealed that this could be associated with an improved stiffness of the wing, while further providing evidence of the vortex development during the flap cycle. The presented experiments resulted in an improvement in the generated lift, allowing the inclusion of a yaw rate gyro, pressure sensor and microcontroller onboard the DelFly. The autonomy of the DelFly is expanded by achieving (1) an improved turning logic to obtain better vision-based obstacle avoidance performance in environments with varying texture and (2) successful onboard height control based on the pressure sensor. PMID:22617112

de Croon, G C H E; Groen, M A; De Wagter, C; Remes, B; Ruijsink, R; van Oudheusden, B W

2012-06-01

433

Metodología de la Encuesta Nacional de Evaluación del Desempeño  

Microsoft Academic Search

Objective. To describe the sampling design, operative strat- egy, and data management used in the Encuesta Nacional de Evaluación del Desempeño (Mexican National Performance Assessment Survey). Material and Methods. A probabil- istic, multistage, stratified sample was used to make infer- ences for each state of the country with representativeness of the urban and rural localities of Mexico. The survey was

Oswaldo Palma-Coca

2005-01-01

434

Inauguracin . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 Universidades y sociedad del conocimiento . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4  

E-print Network

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 Dinámica poblacional, mercados laborales y migraciones . . . . . . . . . . . . . . . . . . . 8 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 #12;U niversidad y sociedad del conocimiento; Dinámi- ca poblacional, mercados laborales y Investigaciones Interdisciplinarias en Ciencias y Hu- manidades, dijo que el seminario fue concebido a partir de

Islas, León

435

La economía del carbón en el Caribe colombiano  

Microsoft Academic Search

La crisis energética que se inició en 1973, despertó en la economía mundial el interés por energéticos sustitutos del petróleo. Colombia no fue la excepción y en la búsqueda de tales sustitutos se asoció en 1976 con una empresa filial de la corporación norteamericana Exxon, para explorar, explotar y exportar los carbones de El Cerrejón Zona Norte, ubicados en el

Joaquín Viloria De La Hoz

1998-01-01

436

Estimación endógena del repudio en mercados soberanos de crédito  

Microsoft Academic Search

En vista de la falta de fundamentos teóricos en la bibliografía relacionada con el repudio en los mercados soberanos de crédito, se construye un modelo que considera todas las peculiaridades de los mercados internacionales de crédito. En particular, se incluye la idea de sanciones en el caso de repudio. Del modelo se extraen diversas conclusiones que contrastan con lo existente.

Fausto Hernández Trillo

1994-01-01

437

Los hijos del terremoto: Imágenes de un recuerdo  

E-print Network

, escapados de los pogroms, que llegaron a América buscando el paraíso. ¿Qué clase de negocio era para ellos el paraíso? Nunca lo supieron, porque el terre moto del absurdo los arrastró al campo a arar esta tierra que no entendían mientras elevaban salmos...

Dauster, Frank

1988-10-01

438

Responsabile del procedimento: Luigi CALISSI UNIVERSIT DEGLI STUDI DI GENOVA  

E-print Network

chirurgiche e diagnostiche integrate (DISC), per il settore scientifico disciplinare MED/08 Anatomia patologica, settore concorsuale 06/A4 Anatomia patologica; Vista la deliberazione del Dipartimento sopra disciplinare MED/08 Anatomia patologica, settore concorsuale 06/A4 Anatomia patologica, di cui alle premesse

Genova, Università degli Studi di

439

Responsabile del procedimento: Luigi CALISSI UNIVERSIT DEGLI STUDI DI GENOVA  

E-print Network

Università, per il settore scientifico disciplinare BIO/06 Anatomia Comparata e Citologia e per il programma il settore scientifico disciplinare BIO/06 Anatomia Comparata e Citologia, di cui alle premesse del giudicatrice: Prof. Mauro VALLARINO - Ordinario inquadrato nel settore scientifico disciplinare BIO/06 Anatomia

Genova, Università degli Studi di

440

Al Prof. Luca Beltrametti Direttore del Dipartimento di Economia  

E-print Network

Mod. D3 Al Prof. Luca Beltrametti Direttore del Dipartimento di Economia Indirizzo Via Vivaldi 5, Darsena, Genova n. fax. 010 2095208 e-mail: direttore@economia.unige.it Oggetto: votazioni in data 18 Economia, con mandato fino al 31.10.2015. Richiesta di pubblicizzazione della disponibilità ad essere

Robbiano, Lorenzo

441

Tratamiento del paludismo pediátrico: Papel de las intervenciones nutricionales  

Microsoft Academic Search

ResumenEl paludismo es una causa primordial de morbilidad y mortalidad en niños, particularmente en África subsahariana. Aunque se ha logrado un progreso considerable en el tratamiento del paludismo pediátrico con el tratamiento de combinación basado en la artemisinina, siguen existiendo numerosos obstáculos que se oponen a la puesta en práctica efectiva de estas nuevas opciones terapéuticas sumamente eficaces. Análogamente, si

Akoto Kwame Osei; Davidson H. Hamer

2008-01-01

442

La fiesta del mulato de Luisa Josefina Hernández  

E-print Network

, 1962), pp. 439-510; La calle de la gran ocasión (Xalapa: Universidad Veracruzana, 1962); Arpas blancas, conejos dorados, en La Palabra y el Hombre, no. 28 (oct-dic 1963), 637-91; La hija del rey, en Cuarta antología de obras en un acto (México...

Nigro, Kirsten F.

1980-07-01

443

I quaderni del Marconi La Biomatematica in un problema  

E-print Network

;3 Presentazione L'ITIS Marconi è stato scelto, per l'a.s. 2005/2006, come scuola Polo per l'attua- zione del Gabriela Freddo Giorgia Marchetto Giacomo Banterle Marco Furlani Dimitri Ruffo Massimiliano Battiston Mattia Gaiga Michele Segna Tommaso Benasi Plinio Longo Marco Scandola Luca Castellani Federico Lorenzi

Zuccher, Simone

444

Breve panorama del teatro en Ecuador durante los años 80  

E-print Network

: el Teatro de la Carpa, constituido por la actriz nacional Támara Navas y el director alemán Christoph Baumann. Lo interesante de su trabajo radica en la interpretación que realizó del texto de Franz Kafka Informe para una Academia la actriz Navas...

Almeida Naveda, Eduardo

1992-04-01

445

Los procesos territoriales del Occidente de México, 1823-1917  

Microsoft Academic Search

El territorio mexicano y particularmente el del occidente, durante el periodo 1823-1917 registró grandes transformaciones en la configuración de sus unidades geopolíticas, tanto en el nivel de las entidades federativas como al interior de ellas; lo cual se interpreta como el resultado de intereses y luchas regionales que se han venido manifestando en la modificación y cambios de ciertas unidades

Hirineo Martínez Barragán

2007-01-01

446

Desconfianza y Desobediencia: Discurso y Práctica del Derecho en México  

Microsoft Academic Search

En agosto del 2002, la Secretaría de Gobernación (SEGOB), junto con la Fundación Este País, publicó los resultados de una encuesta nacional que buscaba evaluar la cultura y prácticas políticas de los mexicanos.[1] De acuerdo con los resultados de la encuesta, el 45% de los encuestados afirmaron creer que ni los ciudadanos ni las autoridades respetaban la ley; el 71%

Catalina Perez Correa

2007-01-01

447

UNIVERSITA' DEL SALENTO Dipartimento di Ingegneria dell'Innovazione  

E-print Network

OF DENSE GAS FLOWS: APPLICATION TO ORGANIC RANKINE CYCLES TURBINES Coordinatore del Ph.D. Ch.mo Prof. Ing by a proper design of the turbine blade. The present work is devoted to improve the understanding-conventional working fluid are pointed out. Then, high performance airfoils and turbine blade shapes for transonic

Paris-Sud XI, Université de

448

Anthropogeography and Rainforest Ecology in Bocas Del Toro Province, Panama.  

National Technical Information Service (NTIS)

The economy of Bocas del Toro province, in northwest Panama, is predominantly bio-technic. Different people have made different uses of the plants and animals of the area over time. Emphasis is placed on the system of Indian silviculture whereby native po...

B. L. Gordon

1969-01-01

449

Análisis del ciclo de vida en proyectos de ingeniería civil  

Microsoft Academic Search

RESUMEN: El propósito de las actividades de análisis y diseño en la ingeniería civil, es determinar, como los factores técnicos y económicos, pueden ser alterados para crear la mayor utilidad al menor costo. En la actua- lidad el análisis del ciclo de vida de proyectos de ingeniería civil, se ha relegado a un concepto netamente teó- rico, es por esto

O. J. Mojica

450

Luchando Infructuosamente contra la Hidra: Un Modelo Sencillo del Narcotráfico  

Microsoft Academic Search

En este artículo se construye un modelo sencillo del narcotráfico que contribuye a explicar dos características notables de esta actividad: la generación de ganancias extraordinarias y la gran capacidad de reproducción en condiciones de prohibición y represión. El modelo establece una relación directa entre la represión a la oferta, la cual ha sido la principal estrategia en la lucha contra

Carlos Humberto Ortiz Q

2000-01-01

451

Parsing bottom-up Idea del parsing bottom-up  

E-print Network

Parsing bottom-up 1 #12;Idea del parsing bottom-up · Costruisce l'abero sintattico iniziando dalle: int * int + int #12;Esempio Il parsing bottom-up riduce una stringa al simbolo iniziale invertendo le parsing bottom-up Sia I la stringa in input repeat prendi una sottostringa non vuota di I dove X e' una

Rossi, Francesca

452

CIENCIA, TECNOLOGA, POLTICA Y PLANIFICACIN DEL AGUA Y DE  

E-print Network

segunda circular enero 2011 CIENCIA, TECNOLOGÍA, POLÍTICA Y PLANIFICACI�N DEL AGUA Y DE LA ENERGÍA EN LOS REGADÍOS. ASPECTOS SOCIOEC�NOMICOS Y AMBIENTALES. AGRICULTURA, AGUA Y ENERGÍA colaboran MADRID varias cuestiones gene- rales que orientan la realización de este Congreso titulado AGRICULTURA, AGUA Y

Escolano, Francisco

453

Synthetic Biology Domitilla Del Vecchio* and Richard M. Murray**  

E-print Network

1 Synthetic Biology Domitilla Del Vecchio* and Richard M. Murray** *Department of Mechanical functions is now pos- sible, leading to the birth of a new field called synthetic biology. Sophisticated functions that are highly sought in synthetic biology range from recognizing and killing cancer cells

Del Vecchio, Domitilla

454

Solar activity and earth rotation variability R. Abarca del Rioa,  

E-print Network

Solar activity and earth rotation variability R. Abarca del Rioa, *, D. Gambisb , D. Salsteinc , P to investigate a possible connection with solar activity fluctuations from interannual to secular time scales in AAM and LOD agrees with that in solar activity with regard to the decadal cycle in the stratospheric

Dai, Aiguo

455

The mercury clock of the Libros del Saber  

Microsoft Academic Search

The Libros del Saber de Astronomia is a compilation of various Arabic astronomical works translated into Castilian in the second half of the thirteenth century, under the direction of King Alfonso X of Spain. A section describing a mercury clock has been suggested to be of particular significance in view of the likely invention of the mechanical clock around this

A. A. Mills

1988-01-01

456

Early evolution of the extraordinary Nova Del 2013 (V339 Del)  

E-print Network

We determine the temporal evolution of the luminosity L(WD), radius R(WD) and effective temperature Teff of the white dwarf (WD) pseudophotosphere of V339 Del from its discovery to around day 40. Another main objective was studying the ionization structure of the ejecta. These aims were achieved by modelling the optical/near-IR spectral energy distribution (SED) using low-resolution spectroscopy (3500 - 9200 A), UBVRcIc and JHKLM photometry. During the fireball stage (Aug. 14.8 - 19.9, 2013), Teff was in the range of 6000 - 12000 K, R(WD) was expanding non-uniformly in time from around 66 to around 300 (d/3 kpc) R(Sun), and L(WD) was super-Eddington, but not constant. After the fireball stage, a large emission measure of 1.0-2.0E+62 (d/3 kpc)**2 cm**(-3) constrained the lower limit of L(WD) to be well above the super-Eddington value. The evolution of the H-alpha line and mainly the transient emergence of the Raman-scattered O VI 1032 A line suggested a biconical ionization structure of the ejecta with a disk-...

Skopal, A; Tarasova, T N; Kato, T; Fujii, M; Teyssier, F; Garde, O; Guarro, J; Edlin, J; Buil, C; Antao, D; Terry, J N; Lemoult, T; Charbonnel, S; Bohlsen, T; Favaro, A; Graham, K

2014-01-01

457

La economa del agua de riego Jos A. Gmez-Limn  

E-print Network

#12;La economía del agua de riego en España José A. Gómez-Limón Javier Calatrava Alberto Garrido Caja Rural, Sociedad Cooperatica de Crédito. La economía del agua de riego en España Todos los derechos Directiva Marco de Agua: ¿Un modelo alternativo del uso del agua? Llorenç Avellà, José Carles y Carles

Oñate, Juan J.

458

Prot. n. P-88/14 Del 24.02.2014  

E-print Network

valore del test del sudore "border-line" e diagnosi incerta di Fibrosi Cistica" da svolgersi presso il Nazionali o Internazionali debitamente attestate nell'ambito della Fibrosi Cistica Pubblicazioni inerenti lo Screening per Fibrosi Cistica - Test del sudore -Genetica della Fibrosi Cistica Ai sensi dell

Guidoni, Leonardo

459

Variation in gestation length as breeding season advances in Bruna dels Pirineus beef cattle breed  

E-print Network

Note Variation in gestation length as breeding season advances in Bruna dels Pirineus beef cattle was investigated in the Bruna dels Pirineus beef cattle breed. A total of 359 gestations belonging to five breeding length / beef cattle / Bruna dels Pirineus Résumé -- Variation de la durée de gestation selon l'avance de

Paris-Sud XI, Université de

460

Efecto del suelo en la tasa de crecimiento de especies tropicales con distribuciones contrastantes  

E-print Network

1 Efecto del suelo en la tasa de crecimiento de especies tropicales con distribuciones contribuir a limitar la distribución de las especies. Uno de ellos es la fertilidad del suelo, la que con frecuencia es menor en los bosques más húmedos. Para evaluar el posible rol de la fertilidad del suelo en la

Bermingham, Eldredge

461

Ciclo de vida del VIH Enlace y fusin: El VIH empieza su ciclo de vida  

E-print Network

VIH debe también ligarse a las proteínas CCR5 ó CXCR4 (co- receptores) para entrar en la célula receptor CD4 glucoproteína del VIH envoltura del VIH CCR5 receptor o CXCR4 receptor Un servicio del

Levin, Judith G.

462

Spectral Characterization of Volcanic Earthquakes at Nevado del Ruiz Volcano Using  

E-print Network

Spectral Characterization of Volcanic Earthquakes at Nevado del Ruiz Volcano Using Spectral Band methods in a two-class classification problem of volcanic earthquakes recorded at Nevado del Ruiz Volcano, seismic-volcanic events, spectral analysis. 1 Introduction Nevado del Ruiz is an ice-capped volcano placed

Duin, Robert P.W.

463

El Mecanismo Causal del Voto de Oposición a una Obra Vial: Una exploración Espacial y Sociológica  

Microsoft Academic Search

Este estudio presenta la geografía y los mecanismos causales del voto de oposición en el plebiscito a la construcción del segundo piso del Periférico en la ciudad de México. Contiene una revisión de la literatura especializada, una descripción de la obra y el plebiscito, sus resultados, indicadores socioeconómicos, y la aplicación de diversas técnicas de estadística espacial y pruebas no

Carlos J. Vilalta y Perdomo

2006-01-01

464

Estudio del Hidrógeno neutro en dirección al remanente de supernova W28  

NASA Astrophysics Data System (ADS)

Se presenta un relevamiento del hidrógeno neutro alrededor del remanente de supernova W28 realizado con el radiotelescopio australiano de Parkes. Se analizan rasgos de emisión y absorción. Se muestra la existencia de estructuras anulares asociadas con el remanente. Se compara la distribución del hidrógeno neutro con la ubicación de máseres de OH detectados en la línea de 1720 MHz.

Dubner, G.; Velazquez, P.; Green, A.; Goss, W. M.; Reynoso, E.

465

Aportació al coneixement florístic de les Guilleries i del Collsacabra (Catalunya Oriental),II  

Microsoft Academic Search

Presentem noves dades corològiques per a la flora vascular dels massissos de les Guilleries i del Collsacabra. En total, tractem 25 tàxons que podem dividir en cinc grups: 1.- nous per a les Guilleries (Peucedanum officinale L., Senecio adonidifolius Loisel., etc.); 2.- nous pel Collsacabra (Carex liparocarpos Gaudin, Seseli tortuosum L., etc.); 3.- nous per un ampli sector del nord-est

Aaron Pérez-Haase; Efrem Batriu; Arnau Mercadé López

2008-01-01

466

del Moral Bibliography Mount St. Helens RECENT RESEARCH PAPERS (links to available papers are provided)  

E-print Network

. American Journal of Botany 92: 27-36. #12;del Moral Bibliography Mount St. Helens Page 2 del Moral, R., D.Mdel Moral Bibliography Mount St. Helens Page 1 RECENT RESEARCH PAPERS (links to available papers are provided): del Moral, R. 2010a. Thirty years of permanent vegetation plots, Mount St. Helens, Washington

del Moral, Roger

467

Contenido del programa de estudios Conceptos generales. Biomolculas. Agua, sus propiedades e interacciones.  

E-print Network

Contenido del programa de estudios Bioquímica Conceptos generales. Biomoléculas. Agua, sus propiedades e interacciones. Hidrofobicidad. Polaridad. Capacidad disolvente del agua. Agua y PH. Constante de disociación del agua y PH. Sistema bicarbonato-ácidocarbónico. Proteínas. Aminoácidos. Características

468

Anlisis de cambios en la calidad del agua en Puerto Rico utilizando Sistemas de  

E-print Network

An�lisis de cambios en la calidad del agua en Puerto Rico utilizando Sistemas de Informaci�n Geogr � Calidad del agua (Puerto Rico) � Maria Uriarte de Columbia University � Charles B. Yackulic , Yili Lim � Calidad del agua (Cuenca Guavate) � Keyla Torres, Elizabeth Pab�n y Fredmarie Oyola, Alexandra Rivera

Gilbes, Fernando

469

Seminario sobre temas estratégicos del agua en América Latina y el Caribe agenda para la acción  

Microsoft Academic Search

En el corto plazo, con apoyo del Banco, América Latina y el Caribe se preparan para elaborar un informe regional sobre financiamiento del agua a ser presentado a las agencias de financiamiento durante el Tercer Foro Mundial del Agua, a llevarse a cabo en 2003 en Kyoto. Para contribuir en este proceso, el Banco organizó el presente seminario e invitó

Jerson Kelman; Benedito Braga; Humberto Peña; César Herrera Toledo; Víctor Pochat; Max Campos; Margaret Catley-Carson; Peter Rogers; Raymundo José Garrido; Adrián Baltanás García; Arnold Sánchez; Herman Rosa; Michel Camdessus; Enrique V. Iglesias; Hyperides Pereira de Macedo; Jamal Saghir; Aser Cortines Peixoto Filho; Sergio Heumann; Linda Kemeny; Fuensanta Díaz Cobacho; Carlos M. Jarque

2002-01-01

470

Esercitazione del 7 marzo 2003 Progetto del sistema di controllo di vibrazione per la sospensione di un'automobile  

E-print Network

di un'automobile (sospensione attiva) Il sistema raffigurato rappresenta lo schema semplificato pneumatico-ammortizzatore-telaio di un'automobile. Il sistema è caratterizzato dalla massa equivalente M dell'automobile esercitare sulla ruota e sul telaio dell'automobile e come azione disturbante d il profilo dell'asperità del

Monaco, Salvatore

471

Esercitazione del 14 febbraio 2003 Progetto del sistema di controllo di vibrazione per la sospensione di un'automobile  

E-print Network

sospensione di un'automobile (sospensione attiva) Il sistema raffigurato rappresenta lo schema semplificato pneumatico-ammortizzatore-telaio di un'automobile. Il sistema è caratterizzato dalla massa equivalente M dell'automobile esercitare sulla ruota e sul telaio dell'automobile e come azione disturbante d il profilo dell'asperità del

Monaco, Salvatore

472

Esercitazione del 21 marzo 2003 Progetto del sistema di controllo di vibrazione per la sospensione di un'automobile  

E-print Network

di un'automobile (sospensione attiva) Il sistema raffigurato rappresenta lo schema semplificato pneumatico-ammortizzatore-telaio di un'automobile. Il sistema è caratterizzato dalla massa equivalente M dell'automobile esercitare sulla ruota e sul telaio dell'automobile e come azione disturbante d il profilo dell'asperità del

Monaco, Salvatore

473

Esercitazione del 28 febbraio 2003 Progetto del sistema di controllo di vibrazione per la sospensione di un'automobile  

E-print Network

sospensione di un'automobile (sospensione attiva) Il sistema raffigurato rappresenta lo schema semplificato pneumatico-ammortizzatore-telaio di un'automobile. Il sistema è caratterizzato dalla massa equivalente M dell'automobile esercitare sulla ruota e sul telaio dell'automobile e come azione disturbante d il profilo dell'asperità del

Monaco, Salvatore

474

ANALISI DEL RISCHIO DI FRATTURA NELL'OSSO SPONGIOSO DEL CORPO VERTEBRALE DI SOGGETTI SANI ED OSTEOPOROTICI  

Microsoft Academic Search

Sommario Obiettivo del presente lavoro è valutare il rischio di frattura dell'osso spongioso nel corpo di una vertebra lombare quando sono modificate proprietà meccaniche dell'osso, - la rigidezza, la porosità, la resistenza anisotropa - di soggetti anziani ed osteoporotici. A tal fine si è messo a punto un modello tridimensionale agli elementi finiti di tipo continuum based dell'unità funzionale spinale

A. Boccaccio; P. Vena; D. Gastaldi

475

LA CONSOLIDACIÓN DEL HAMBRE Y DEL DERECHO A LA ALIMENTACIÓN EN LAS AGENDAS POLÍTICAS DE AMÉRICA LATINA  

Microsoft Academic Search

América Latina y el Caribe es la única región en desarrollo que puede acabar con el hambre en nuestra generación. Tiene 52,4 millones de personas subnutridas (10% de población) y 9 millones de niños con desnutrición crónica, pero también es la principal productora mundial de alimentos y tiene recursos financieros, naturales, humanos e institucionales para hacer del hambre un recuerdo

Jose Luis Viveros; Niemeyer Almeida Filho

2008-01-01

476

La democracia constitucional en América Latina y las evoluciones recientes del presidencialismo. Memorias Encuentro del Instituto Iberoamericano de Derecho Constitucional  

Microsoft Academic Search

Siempre será oportuno reflexionar sobre la democracia, su contenido, sus desafíos, su presente y su futuro, las transformaciones y percepciones que de ella se tienen. No son pocas las preocupaciones o inquietudes que la democracia suscita en esta parte del mundo, y muestra de ello son los más variados estudios e informes sobre el estado actual de la democracia y

Pedro Pablo Vanegas

477

Futuro de las telecomunicaciones en México ¿Cuál debe ser el rol del gobierno ante los nuevos escenarios del mercado?  

Microsoft Academic Search

El objetivo del presente artículo es analizar las decisiones de política pública que está llevando a cabo el gobierno de México para impulsar la competencia en el mercado de telecomunicaciones. Para ello, se identifica la forma en la que está organizado este sector y se utilizan herramientas provenientes de la teoría económica de redes para evaluar las acciones de este

Fernando G. Toriz Flores

2010-01-01

478

LA GLOBALIZACIÓN Y EL DESARROLLO LOCAL (EL PROBLEMA DEL DESEMPLEO) ESTUDIO DE CASO DEL MUNICIPIO DE APIZACO, TLAXCALA, MEXICO  

Microsoft Academic Search

La globalización y el desarrollo local son términos utilizados en diversos foros internacionales de la vida económica, política y social. Para los países que hoy forman parte del consenso de Washington, es un tema de primer orden. Así, la globalización permea las políticas, sociales, económicas y financieras para los países emergentes, las cuales representan para algunos países beneficios y para

Lorenzo Salgado García

2007-01-01

479

Sueo y conversin. Reelaboracin, dramatizacin y funcin del motivo del eunuco de Candaces en dos autos de Caldern  

E-print Network

agua, y dijo el eunuco: Aquí hay agua; ¿qué impide que yo sea bautizado? Felipe dijo: Si crees de todo carro; y descendieron ambos al agua, Felipe y el eunuco, y le bautizó. / Cuando subieron del agua, el

Boyer, Edmond

480

Estudios en la Zona no Saturada del Suelo. Vol X ALGORITMO MECANSTICO SIMPLIFICADO PARA LA CUANTIFICACIN DEL EFECTO DE UN  

E-print Network

se estudia la extensión de la ecuación de Green-Ampt para la infiltración de agua en presencia de un encharcamiento del suelo y balance de agua durante un hietograma de lluvia natural. El modelo se contrasta

Boyer, Edmond

481

Programa de Apoyos para la Superacin del Personal Acadmico de la UNAM Resultados del 2 periodo de la convocatoria 2011  

E-print Network

Colegio de Ciencias y Humanidades Maestría Bassiouk Evdokimenko Vladimir Instituto de Ciencias Nucleares Vladimir Instituto de Ciencias Nucleares Estancia Sabática Blancas Neria Andrés Instituto de de Geología Estancia Sabática Castañeda Serrano María Del Pilar Facultad de Medicina Veterinaria y

Islas, León

482

Evidence for single origins of 35delG and delE120 mutations in the GJB2 gene in Anatolia.  

PubMed

Eighteen different sequence changes, including three novel alterations, were detected in GJB2, encoding connexin 26, in 371 Turkish probands with non-syndromic sensorineural hearing loss. Two frequently detected mutations, 35delG and delE120, were shown to have single origins based on the conserved genotypes of two closely linked microsatellite and five single nucleotide polymorphism markers. Carrier frequencies of 35delG and delE120 in Egypt and Turkic populations of the Near East provide insights about the origin of these two mutations. PMID:15617546

Tekin, M; Bo?oclu, G; Arican, S T; Orman, M N; Tastan, H; Elsobky, E; Elsayed, S; Akar, N

2005-01-01

483

Estudios de la Zona No Saturada del Suelo Vol. VI. J. lvarez-Bened y P. Marinero, 2003 ELIMINACIN DE NITRATOS POR DESNITRIFICACIN EN LA ZONA NO SATURADA DEL SUELO EN  

E-print Network

Estudios de la Zona No Saturada del Suelo Vol. VI. J. Álvarez-Benedí y P. Marinero, 2003 385 ELIMINACI�N DE NITRATOS POR DESNITRIFICACI�N EN LA ZONA NO SATURADA DEL SUELO EN UN HUMEDAL DEL CINTUR�N PERI-Euskal Herriko Unibertsitatea, 48940 Leioa (Bizkaia), gopanaui@lg.ehu.es. RESUMEN. Los cambios de usos del suelo

Chave, Jérôme

484

Uso del agua activada y con tratamiento magnético del tomate en condiciones de organopónico Use of the activated water and with magnetic treatment of the tomato under organoponics conditions  

Microsoft Academic Search

RESUMEN. Se realizó una investigación en el organopónico del Instituto de Investigaciones de Riego y Drenaje (IIRD), durante dos años sobre la aplicación del agua con tratamientos físico- químicos (activación y magnetización) para el riego del tomate variedad Rilia. Durante el período, se estudió la dinámica de crecimiento estableciéndose las diferencias entre los tratamientos de magnetización y activación del agua

Carmen E. Duarte; Greter Guevara; Maykel Méndez

485

El presidente Obama anuncia nombramiento del doctor Harold Varmus  

Cancer.gov

En un correo electrónico enviado al personal del NCI, el doctor Francis Collins, director de los Institutos Nacionales de la Salud, dijo que Varmus “trae consigo un experiencia sin igual a todo nivel, no solo en la investigación científica más avanzada, sino también como líder en la creación de estrategias para mejorar el cuidado de los pacientes, la educación científica, la capacitación y el diseño de novedosas alianzas entre el sector público y el privado”.

486

Prenatal Care in the Paso del Norte Border Region  

Microsoft Academic Search

OBJECTIVES: The impact of a Medicaid-managed care system on access to prenatal care was investigated.STUDY DESIGN: Postpartum interviews and medical chart abstractions were conducted among 493 Hispanic women who reside on the El Paso Texas\\/Juarez Mexico border (the Paso del Norte region). Descriptive analysis identified barriers and facilitators to prenatal care. Logistic regression identified the impact of social and demographic

Judith T Fullerton; Carlene Nelson; Rachel Shannon; Julia Bader

2004-01-01

487

Del carnaval como 'metáfora' al teatro de carnaval  

E-print Network

ocasiones "sus piruetas van llenando la noche de fantasía, todo es color y alegría." Pese a sus "gracias" y burlas es un dios sorprendentemente obediente y burocrático, que se detiene ante los límites y tabúes trazados por la cultura hegemónica ("debe..." (que separa al escenario de la platea y al murguista del público), lo mismo mantiene "la quinta pared" que separa el tablado de la calle. Estas representaciones también se caracterizan por la búsqueda de conformar a las autoridades, por estar...

Remedi, Gustavo

2001-04-01

488

Wetlands of the Magellanic Steppe (Tierra Del Fuego, Argentina)  

Microsoft Academic Search

Our main objective was to classify vegetation and soils of wetlands in northern Tierra del Fuego (Argentina) along a latitudinal\\u000a precipitation gradient within the Magellanic Steppe Zone. We presented the first detailed ecological characterization of these\\u000a wetlands by relating floristic composition to local site conditions, bedrock and climate. The survey consisted of 125 phytosociological\\u000a censuses and 52 soil profile descriptions.

Marta B. Collantes; Juan A. Anchorena; Susana Stoffella; Celina Escartín; Ruth Rauber

2009-01-01

489

La computacin y sus versiones : El Debate del Software  

E-print Network

La computación y sus versiones : El Debate del Software Software Libre vs. Software Privativo Pablo controladas por el código (el software). Pero ... ¿Quién controla el código? ¿De quién recibe órdenes tu computadora? ¿Tenemos derecho a saber exactamente qué hace nuestra computadora? #12;¿Qué es el Software Libre

De Nápoli, Pablo Luis

490

La generación de 1924: El dilema del realismo  

E-print Network

posible en el medioambiente—un teatro hecho dentro de los contornos del realismo burgués contra el cual habían peleado tan duramente, y al parecer, tan sin éxito. Pero sólo al parecer. Para comprender el alcance de Ulises, solamente hay que comparar... tono serio gidiano a pesar de su aplastante ironía. Curiosamente, es de construcción realista, aunque una muy problemática representación habría tenido que recurrir a una estilización poco realista. Como los Autos de Villaurrutia, relaciona una...

Dauster, Frank

1985-04-01

491

Le Thorium Molten Salt Reactor : Au del du MSBR  

E-print Network

Le Thorium Molten Salt Reactor : Au delà du MSBR L. Mathieu, D. Heuer, A. Billebaud, R. Brissot, C Général De Gaulle, 92140 Clamart, France Résumé La ré-évaluation du concept de Molten Salt Breeder Reactor réflexion est menée afin de trou- ver des solutions et ainsi d'aboutir au concept du Thorium Mol- ten Salt

Paris-Sud XI, Université de

492

Récord de longevidad del Correlimos Zarapitín (Calidris ferruginea)  

Microsoft Academic Search

En aquesta nota es descriu el control d'un territ bec-llarg disset anys després del seu anellament. L'ocell es va marcar com a jove el 5 de setembre de 1975 a Friesland (Holanda) i es va recapturar el 3 d'agost de 1992 al delta de l'Ebre, 6173 dies després de l'anellament. Fins ara la màxima longevitat demostrada per a aquesta espècie

Jordi Figuerola

1995-01-01

493

Polymorphisms of ? - defensin genes in Valle del Belice dairy sheep  

Microsoft Academic Search

The aim of this work was to study ?-defensin 1 (SBD1) and ?-defensin 2 (SBD2) genes in Valle del Belice dairy sheep in order to identify polymorphisms that can be utilized as markers of the analyzed\\u000a genes, and search for the functional effects and roles of the identified polymorphisms (variation of the amino acid sequence\\u000a of the protein and stability

Giuseppina Monteleone; Davide Calascibetta; Mariangela Scaturro; Paola Galluzzo; Marisa Palmeri; Valentina Riggio; Baldassare Portolano

494

2. COURSE OF THE LATERAL THROUGH DEL NORTHWEST MAR PARK. ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

2. COURSE OF THE LATERAL THROUGH DEL NORTHWEST MAR PARK. - Highline Canal, Sand Creek Lateral, Beginning at intersection of Peoria Street & Highline Canal in Arapahoe County (City of Aurora), Sand Creek lateral Extends 15 miles Northerly through Araphoe County, City & County of Denver, & Adams County to its end point, approximately 1/4 mile Southest of intersectioin of D Street & Ninth Avenue in Adams County (Rocky Mountain Arsenal, Commerce City Vicinity), Commerce City, Adams County, CO

495

Talleres del primer cuatrimestre. Curso 2013-2014 LAS TARDES DE CINE. CINE EN VERSIN ORIGINAL EN EL MACA  

E-print Network

Talleres del primer cuatrimestre. Curso 2013-2014 1 LAS TARDES DE CINE. CINE EN VERSIÃ?N ORIGINAL EN: 88 min. #12;Talleres del primer cuatrimestre. Curso 2013-2014 2 12 de diciembre Un pez llamado Wanda EVALUACIÃ?N PROPUESTA POR EL PROFESOR *REALIZAR LA ENCUESTA DE SATISFACCIÃ?N DEL CURSO #12;Talleres del primer

Escolano, Francisco

496

La "conversione" delle cellule della cute che producono insulina: nuova arma contro diabete e tumore del pancreas  

E-print Network

tumore del pancreas Uno studio dell'Università degli Studi di Milano su PNAS scopre un metodo, sicuro alterarne il DNA. Straordinarie le potenzialità nella terapia del diabete e del tumore al pancreas. La i vari tipi di diabete e per il tumore del pancreas. La ricerca, finanziata da AIRC, MIUR e Regione

De Cindio, Fiorella

497

Economia del Sistema Foresta-Legno 2001-2002 26-11-2011 Gestione dei beni comuni  

E-print Network

Economia del Sistema Foresta-Legno 2001-2002 26-11-2011 1 Gestione dei beni comuni: esperienze 70% del fabbisogno energetico delle popolazioni africane e del sud-est asiatico. · Economia informale;Economia del Sistema Foresta-Legno 2001-2002 26-11-2011 2 Uno sviluppo diseguale Cambiamenti della

Pettenella, Davide

498

Consejo Asesor del Decanato de Estudios Tecnolgicos Acta 10-2011 Pg. 1 de 3 UNIVERSIDAD SIMON BOLIVAR  

E-print Network

Litoral; la TSU. Ana Rosa Ibañez, Asesora del Decano y el Lic. William Contreras, Asistente al Decano Normas y Procedimientos del Decanato y de las Coordinaciones Docentes. 1. Consideración del Orden del Día

Vásquez, Carlos

499

Estudios de la Zona No Saturada del Suelo Vol. VI. J.lvarez-Bened y P. Marinero, 2003 MODELIZACIN Y SIMULACIN NUMRICA DEL TRANSPORTE DE SOLUTOS VOLTILES NO  

E-print Network

Estudios de la Zona No Saturada del Suelo Vol. VI. J.Álvarez-Benedí y P. Marinero, 2003 245 acciones de restauración de suelos contaminados. Algunos compuestos químicos son solubles en agua y las propiedades hidráulicas del suelo en la zona no saturada (Karagunduz et al. 2001; Feng et al

Politècnica de Catalunya, Universitat

500

Nuevo sitio web en español del Instituto Nacional del Cáncer, (NCI, por sus siglas en inglés) Cancer.gov en español - Silvia Inéz Salazar - transcript  

Cancer.gov

Transmisiones de radio para promover Cancer.gov en espa%XF1ol | Nuevo sitio web en espa%XF1ol del Instituto Nacional del C%XE1ncer, (NCI, por sus siglas en ingl%XE9s) Cancer.gov en espa%XF1ol | Transcripci%XF3n Transmisiones de radio para promover