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1

Tertiary Flow Injection Thrust Vectoring System.  

National Technical Information Service (NTIS)

The tertiary flow injection thrust vectoring system adds to the secondary injection system disclosed in patent No. 3,144,752. The system involves the feature of a small amount of mass injection upstream of the secondary injection port to distort the prima...

C. E. Kepler

1965-01-01

2

Robust synthesized control of electromechanical actuator for thrust vector system in spacecraft  

Microsoft Academic Search

A kind of robust control of electromechanical actuator (EMA) system for thrust vector control in a spacecraft was investigated. In the flight of a spacecraft, the EMA system must overcome the influence of load disturbance and working point alteration to improve the robust control performances. Addressing this problem and considering the large inertia and low stiffness load of the EMA

Hao Lu; Yunhua Li; Chenglin Zhu

3

Posture Control of Electromechanical-Actuator-Based Thrust Vector System for Aircraft Engine  

Microsoft Academic Search

This paper deals with the dynamical modeling and posture control of the electromechanical actuator (EMA)-based thrust vector control (TVC) system for aircraft engines. Addressing the issues of the large inertia and low stiffness existing in the TVC system driven by EMA, this paper established a 2-DOF mathematical model to describe the EMA dynamic characteristics. In order to overcome the influence

Yunhua Li; Hao Lu; Shengli Tian; Zongxia Jiao; Jian-Tao Chen

2012-01-01

4

Effect of Coflow on Counterflow Thrust Vectoring  

Microsoft Academic Search

A unique, fluidic-based thrust vectoring technique known as CounterFlow Thrust Vector Control (CFTVC) has been investigated at the Fluid Mechanics Research Laboratory (FMRL) over the past few years. These studies have demonstrated that CFTVC is a simple, robust and efficient method for thrust vectoring of supersonic jets of various geometries. In an effort to better evaluate the system performance under

F. S. Alvi; A. Krothapalli; P. J. Strykowski

1997-01-01

5

Three-axis asymmetric radiation detector system  

DOEpatents

A three-axis radiation detection system whose inner and outer electrodes are shaped and positioned so that the shortest path between any point on the inner electrode and the outer electrode is a different length whereby the rise time of a pulse derived from a detected radiation event can uniquely define the azimuthal and radial position of that event, and the outer electrode is divided into a plurality of segments in the longitudinal axial direction for locating the axial location of a radiation detection event occurring in the diode.

Martini, Mario Pierangelo (Oak Ridge, TN); Gedcke, Dale A. (Oak Ridge, TN); Raudorf, Thomas W. (Oak Ridge, TN); Sangsingkeow, Pat (Knoxville, TN)

2000-01-01

6

Fluidic thrust vector control  

NASA Astrophysics Data System (ADS)

The design and testing of a fluidic control nozzle for tactical missile thrust vector control (TVC) are discussed. Attention is given to a nozzle with a circular cross section up to the point of flow separation, two control ports that alternately open and close, and a nozzle extension downstream of the control ports being a two-dimensional rectangular slot. Design of the TVC system involved characterizing the flow and the sensitivity parameters, the dynamic response, and the performance of hot-gas firings. The test firings verified the feasibility of a nozzle that could withstand 5000 F, the use of thrust vector angles of over 20 deg. A dynamic model test demonstrated a repeatable performance with pressures up to 2000 psia, driving frequencies up to 50 Hz, and a response of 10-15 msec. Adjustment of the chamber pressures permitted equivalent performance using with different heat ratios during cold dynamic tests with CH4.

Haloulakos, V. E.

7

Fluidic Servoactuators for Three-Axis Fluidic Stability Augmentation System.  

National Technical Information Service (NTIS)

The report covers the developmental work accomplished on a program to furnish three fluidic servoactuators for a three-axis fluidic stability augmentation system (FSAS). The servoactuators, designed to the specification for a helicopter flight control sys...

T. S. Honda

1970-01-01

8

Fluidic thrust vector control  

Microsoft Academic Search

The design and testing of a fluidic control nozzle for tactical missile thrust vector control (TVC) are discussed. Attention is given to a nozzle with a circular cross section up to the point of flow separation, two control ports that alternately open and close, and a nozzle extension downstream of the control ports being a two-dimensional rectangular slot. Design of

V. E. Haloulakos

1982-01-01

9

Thrust vector control using electric actuation  

Microsoft Academic Search

Presently, gimbaling of launch vehicle engines for thrust vector control is generally accomplished using a hydraulic system. In the case of the space shuttle solid rocket boosters and main engines, these systems are powered by hydrazine auxiliary power units. Use of electromechanical actuators would provide significant advantages in cost and maintenance. However, present energy source technologies such as batteries are

Robert T. Bechtel; David K. Hall

1995-01-01

10

Miniature image guided three-axis scanning and positioning system  

NASA Astrophysics Data System (ADS)

We have developed a high precision three axes scanning and positioning system for integration with Multifunctional Image Guided Surgical (MIGS) Platform. The stage integrates three main components: an optical coherence tomography (OCT) probe, laser scalpel and suction cup. The requirements for this stage were to provide scanning area of 400mm2, resolution of less than 10 microns and scanning velocity in the range of 10 - 40 mm/s. The stage was modeled using computer aided design software NX Unigraphics. In addition to the parameters mentioned above, additional boundary conditions for the stage were set as low volume and modularity. Optimized stage model was fabricated by using rapid prototyping technique that integrates low cost stepper motors, threaded rod drive train and a stepper motor controller. The EZ4axis stepper motor controller was able to provide 1/8th microstep resolution control over the motors, which met the criterion desired for the MIGS platform. Integration of computer controlled three-axis stage with MIGS platform provides the opportunity for conducting intricate surgical procedures using remote control or joystick. The device is image guided using the OCT probe and it is able to pin point any location requiring a laser scalpel incision. Due to the scanning capabilities, a high quality threedimensional image of the tissue topography is obtained which allows the surgeon to make a confident decision of where to apply the laser scalpel and make an incision.

Avirovik, Dragan; Dave, Digant; Priya, Shashank

2012-03-01

11

Haptic controlled three-axis MEMS gripper system.  

PubMed

In this work, we describe the development and testing of a three degree of freedom meso/micromanipulation system for handling micro-objects, including biological cells and microbeads. Three-axis control is obtained using stepper motors coupled to micromanipulators. The test specimen is placed on a linear X-stage, which is coupled to one stepper motor. The remaining two stepper motors are coupled to the Y and Z axes of a micromanipulator. The stepper motor-micromanipulator arrangement in the Y and Z axes has a minimum step resolution of ?0.4??m with a total travel of 12 mm and the stepper motor-X stage arrangement has a minimum resolution of ?0.3??m with a total travel of 10 mm. Mechanical backlash error is ?0.8??m for ?750??m of travel. A MEMS microgripper from Femtotools™ acts as an end-effector in the shaft end of the micromanipulator. The gripping ranges of the grippers used are 0-100??m (for FT-G100) and 0-60??m (for FT-G60). As the gripping action is performed, the force sense circuit of FT-G100 measures the handling force. This force feedback is integrated to a commercially available three degree of freedom haptic device (Novint Falcon) allowing the user to receive tactile feedback during the microscale handling. Both mesoscale and microscale controls are important, as mesoscale control is required for the travel motion of the test object whereas microscale control is required for the gripping action. The haptic device is used to control the position of the microgripper, control the actuation of the microgripper, and provide force feedback. A LABVIEW program was developed to interlink communication and control among hardware used in the system. Micro-objects such as SF-9 cells and polystyrene beads (?45??m) are handled and handling forces of ?50??N were experienced. PMID:21034126

Vijayasai, Ashwin P; Sivakumar, Ganapathy; Mulsow, Matthew; Lacouture, Shelby; Holness, Alex; Dallas, Tim E

2010-10-01

12

Effect of Coflow on Counterflow Thrust Vectoring  

NASA Astrophysics Data System (ADS)

A unique, fluidic-based thrust vectoring technique known as CounterFlow Thrust Vector Control (CFTVC) has been investigated at the Fluid Mechanics Research Laboratory (FMRL) over the past few years. These studies have demonstrated that CFTVC is a simple, robust and efficient method for thrust vectoring of supersonic jets of various geometries. In an effort to better evaluate the system performance under real flight conditions, a study of the CFTVC system under "wind-on" conditions, using a rectangular Mach 1.4 jet, is currently in progress. The wind-on condition is simulated by providing a coflowing stream (i.e. flowing in the same direction as the primary jet) at the periphery of the countercurrent stream which surrounds the primary jet. Coflowing streams over a range of Mach numbers, from 0.3 to 0.7, will be tested. Preliminary results show that the coflowing stream has a relatively minor influence on CFTVC and that the jet can be easily vectored to large angles in the presence of coflow. These encouraging reuslts further demonstrate the potential of this system for future propulsion applications.

Alvi, F. S.; Krothapalli, A.; Strykowski, P. J.

1997-11-01

13

Solid Rocket Booster Thrust Vector Control Subsystem Description.  

National Technical Information Service (NTIS)

Major Solid Rocket Booster-Thrust Vector Control (SRB-TVC) subsystem components and subcomponents used in the Space Transportation System (STS) are identified. Simplified schematics, detailed schematics, figures, photographs, and data are included to acqu...

J. Redmon

1983-01-01

14

Feedback control for counterflow thrust vectoring  

Microsoft Academic Search

Thrust vector control is used to increase the maneuverability of aircraft. In current aircraft it is implemented using movable control surfaces such as vanes and flaps. Counterflow thrust vectoring (CFTV) is a fluidic approach to thrust vectoring that has the potential to improve on the conventional approaches by reducing weight and increasing the reaction speed. Open loop implementation of CFTV

Emmanuel G. Collins; Yanan Zhao; F. Alvi; M. I. Alidu; P. J. Strykowski

2004-01-01

15

Experimental Study On Counter Flow Thrust Vector Control  

NASA Astrophysics Data System (ADS)

Counter Flow Thrust Vectoring (CFTV) is possibly the most promising fluidic thrust vector control method for deflecting the exhaust thrust of a jet engine. CFTV works by generating a countercurrent shear layer in one side of a planar jet and hence by altering the transverse pressure gradient across the jet. Prediction and control of vector angle is the most important aspect in any thrust vectoring system. Experiments are conducted to obtain pressure distribution on the collar surface, which is used with a vacuum system to generate counter flow on one side of a rectangular (aspect ratio 4:1) jet. The exit Mach number of the ideally expanded jet considered here is 1.44. Gap height between the nozzle and collar surface is varied and vector angle for different mass flow rate has been obtained. The condition at which the jet attaches with the collar surface is found and compared with the predicted theoretical results.

Madruga, Maria S.; Das, Debopam; Strykowski, Paul J.

2000-11-01

16

Design and test of electromechanical actuators for thrust vector control  

Microsoft Academic Search

New control mechanisms technologies are currently being explored to provide alternatives to hydraulic thrust vector control (TVC) actuation systems. For many years engineers have been encouraging the investigation of electromechanical actuators (EMA) to take the place of hydraulics for spacecraft control\\/gimballing systems. The rationale is to deliver a lighter, cleaner, safer, more easily maintained, as well as energy efficient space

J. R. Cowan; Rae Ann Weir

1993-01-01

17

Control and breakthrough detection of a three-axis robotic bone drilling system  

Microsoft Academic Search

This paper describes a robotic bone drilling system for applications in orthopedic surgery. The goal is to realize a three-axis robotic drilling system which can automatically stop drilling at the moment a drill breaks through bone. The proposed robotic bone drilling system consists of an inner loop fuzzy controller for robot position control, and an outer loop PD controller for

Wen-Yo Lee; Ching-Long Shih

2006-01-01

18

SUMMARY OF FLUIDIC THRUST VECTORING RESEARCH CONDUCTED AT NASA LANGLEY RESEARCH CENTER  

Microsoft Academic Search

Interest in low-observable aircraft and in lowering an aircraft's exhaust system weight sparked decades of research for fixed geometry exhaust nozzles. The desire for such integrated exhaust nozzles was the catalyst for new fluidic control techniques; including throat area control, expansion control, and thrust-vector angle control. This paper summarizes a variety of fluidic thrust vectoring concepts that have been tested

Karen A. Deere

2003-01-01

19

Computational Investigation of Fluidic Counterflow Thrust Vectoring.  

National Technical Information Service (NTIS)

A computational study of fluidic counterflow thrust vectoring has been conducted. Two-dimensional numerical simulations were run using the computational fluid dynamics code PAB3D with two-equation turbulence closure and linear Reynolds stress modeling. Fo...

C. A. Hunter K. A. Deere

1999-01-01

20

Characteristics of a confined jet thrust vector control nozzle  

Microsoft Academic Search

A study of confined jet thrust vector control (CJTVC) is presented. By isolating an area of flow separation within the body of a nozzle, CJTVC has the advantage over other thrust vector controls using secondary injection (SI) in that it can operate independent of altitude. This makes it ideal for applications in small missiles and spacecraft attitude control. In this

A. J. Porzio

1984-01-01

21

Experimental Study On Counter Flow Thrust Vector Control  

Microsoft Academic Search

Counter Flow Thrust Vectoring (CFTV) is possibly the most promising fluidic thrust vector control method for deflecting the exhaust thrust of a jet engine. CFTV works by generating a countercurrent shear layer in one side of a planar jet and hence by altering the transverse pressure gradient across the jet. Prediction and control of vector angle is the most important

Maria S. Madruga; Debopam Das; Paul J. Strykowski

2000-01-01

22

Development and qualification of a STAR 48 rocket motor with thrust vector control  

NASA Astrophysics Data System (ADS)

A thrust vector control (TVC) nozzle for use on the STAR 48 rocket motor (STAR 48V) has been developed for use on the COMET program aboard the Conestoga launch vehicle. The first stages of qualification testing have been completed. The first STAR 48V has been successfully static-tested. The flexseal TVC nozzle design is based upon the qualified and flight-proven fixed nozzle design used on spin-stabilized spacecraft. The flexseal design and fabrication approach benefit from flight-proven and man-rated Thiokol Corporation flexseal designs. The thrust vector control system provides vectoring capability to 4 deg for use on nonspinning spacecraft. Electromechanical actuators coupled with a closed-loop controller provide thrust vector positioning and spacecraft attitude control.

Hamke, R.; Rade, J.; Weldin, R.

1992-07-01

23

An integrated micro HTS system for energy storage and attitude control for three-axis stabilized nanosatellites  

Microsoft Academic Search

This paper presents the development of an integrated micro high-temperature superconductor system for energy storage and attitude control of three-axis stabilized nano satellites. The micro HTS system consists of a flywheel\\/rotor, motor\\/generator, motor electronics, and a cooling system. The flywheel\\/rotor has been fabricated by using sintered NdFeB and the stator for motor\\/generator has been fabricated by micro fabrication technology. An

Eunjeong Lee; Bongsu Kim; Junseok Ko; Chi Young Song; Seong-Jin Kim; Sangkwon Jeong; Seung S. Lee

2005-01-01

24

Reduced-length scarfed-nozzles for thrust vector adjustment  

NASA Astrophysics Data System (ADS)

The results of an investigation into the utilization of scarfed, truncated perfect-nozzles for thrust vector adjustment in tactical strap-on boosters is presented. The use of truncated perfect-nozzle expansion contours was evaluated as a means of achieving significant nozzle length reductions over conical nozzle designs without degrading axial thrust or thrust vector adjustment capability. Previously developed perfect-nozzle and scarfed-nozzle performance analysis computer codes were used to generate an extensive parametric study which characterized the influence of nozzle length and expansion ratio on axial thrust and thrust vector adjustment capability. Comparisons were made against the results obtained for scarfed-nozzles with conical expansion contours. The parametric study was utilized to develop a general scarfed truncated perfect-nozzle design. The axial performance and thrust vector adjustment capability of the nozzle design was experimentally verified through solid rocket motor static firings.

Lilley, Jay S.

1993-04-01

25

Computational Investigation of the Aerodynamic Effects on Fluidic Thrust Vectoring.  

National Technical Information Service (NTIS)

A computational investigation of the aerodynamic effects on fluidic thrust vectoring has been conducted. Three-dimensional simulations of a two-dimensional, convergent-divergent (2DCD) nozzle with fluidic injection for pitch vector control were run with t...

K. A. Deere

2000-01-01

26

Three-axis active control system for gravity gradient stabilised microsatellite  

Microsoft Academic Search

In this paper, the control system of the first Algerian microsatellite in orbit Alsat-1 is presented. Alsat-1 is a 3-axis stabilised microsatellite, using a pitch momentum wheel and yaw reaction wheel, with dual redundant 3-axis magnetorquers. A gravity gradient boom is employed to provide a high degree of platform stability. Two vector magnetometers and four dual sun sensors are carried

A. M. Si Mohammed; M. Benyettou; Y. Bentoutou; A. Boudjemai; Y. Hashida; M. N. Sweeting

2009-01-01

27

Ground Test of the D Shaped Vented Thrust Vectoring Nozzle.  

National Technical Information Service (NTIS)

Static ground tests of a large scale lift/cruise thrust vectoring nozzle were conducted to establish: (1) vectoring performance 'in' and 'out' of ground effect; (2) thrust spoilage capability; (3) compatibility of the nozzle with a turbotip fan; and (4) t...

D. W. Esker

1976-01-01

28

Design Enhancements of the Two-Dimensional, Dual Throat Fluidic Thrust Vectoring Nozzle Concept.  

National Technical Information Service (NTIS)

A Dual Throat Nozzle fluidic thrust vectoring technique that achieves higher thrust-vectoring efficiencies than other fluidic techniques, without sacrificing thrust efficiency has been developed at NASA Langley Research Center. The nozzle concept was desi...

J. D. Flamm K. A. Deere M. L. Mason B. L. Berrier S. K. Johnson

2006-01-01

29

Refractory Air Vane and Refractory Material Research and Development. Task II - Refractory Materials for a Thrust Vector Control Valve.  

National Technical Information Service (NTIS)

This document reports the results of a 12-month contract to evaluate candidate refractory and insulator materials for use as the inlet duct liner, rotor, and nozzle exit, of a hot gas thrust vector control system. The purpose of this investigation was to ...

S. B. Moorhead

1974-01-01

30

Combining Countercurrent Shear Flow Control and Transverse Jets for Fluidic Thrust Vector Control  

Microsoft Academic Search

Countercurrent shear flow control has been established as an effective method for thrust vector control but has been challenged by hardware integration issues. Recent developments in fluidic thrust vector control have focused on nozzle interior methods that skew the throat of the nozzle using multiple transverse jets. The present work is motivated to combine these two flow control approaches to

Ignacio Echavarria Diaz-Guardamino; David Forliti

2007-01-01

31

COMPUTATIONAL STUDY OF FLUIDIC THRUST VECTORING USING SEPARATION CONTROL IN A NOZZLE  

Microsoft Academic Search

A computational investigation of a two- dimensional nozzle was completed to assess the use of fluidic injection to manipulate flow separation and cause thrust vectoring of the primary jet thrust. The nozzle was designed with a recessed cavity to enhance the throat shifting method of fluidic thrust vectoring. The structured-grid, computational fluid dynamics code PAB3D was used to guide the

Karen A. Deere; Bobby L. Berrier; Jeffrey D. Flamm

2003-01-01

32

An experimental investigation of active control of thrust vectoring nozzle flow fields  

Microsoft Academic Search

Fluidic thrust vector control is examined in a supersonic rectangular jet having a 4:1 aspect ratio. Experiments conducted at a Mach number of 2 reveal that the thrust vector angle of the jet can be continuously varied by up to at least 16 deg by applying a counterflowing stream to one of the primary jet shear layers. A technique using

P. J. Strykowski; A. Krothapalli

1994-01-01

33

Design and evaluation of single and dual flow thrust vector nozzles with post exit vanes  

NASA Astrophysics Data System (ADS)

This Thrust Vectored Research project required that a 1/24 scale model of the F/A-18 High Alpha Research Vehicle, (HARV), propulsion system be constructed on the university campus. This propulsion system was designed for cold flow testing on a multicomponent test rig. Forces and moments were measured to study nozzle performance parameters. The flow visualization technique of color Schlieren photography was performed to investigate the flow phenomena at the nozzle exit. The flow interactions that were identified consisted of vane nozzleing between the outer and lower vanes and vane tip interference. The thrust vectoring system consisted of three asymmetrically spaced vanes installed circumferentially on a maximum afterburner nozzle. The performance of the nozzle was investigated with the outer and lower vanes equally deflected, (-10 deg is less than delta(sub v) is less than 25 deg), and with the upper vane fully retracted, (delta(sub v) equals -10 deg). The nozzle pressure ratio ranged from 4 to 6. The results indicated that a vane nozzleing effect developed at nozzle pressure ratios of 4 and 6 when the outer and lower vanes were deflected far enough into the flow field such that the increase in vane area accelerated the flow past the vanes causing distorted shock waves. This accelerated flow was a result of a pressure differential existing between the inside surface of the vane and the ambient pressure. The stagnation pressure that developed along the inside surface of the vane accelerated the flow past the vanes causing it to equalize with ambient pressure, thus providing distorted shock waves. A tip interference was present at the trailing edge of the upper vane as a result of low nozzle pressure, NPR 4, with high vane deflection, delta(sub v) equals 25 degrees, and also with a high nozzle pressure, NPR 6, and low vane deflections, delta(sub v) equals 15 degrees.

Carpenter, Thomas W.; Vaccarezza, Stephen E.; Dobbins, Sean

1992-12-01

34

Experimental Evaluation of Design Variables for Two-Dimensional Confined Jet Thrust Vector Control Nozzles.  

National Technical Information Service (NTIS)

An experimental study of the axial and vectoring performance of two - dimensional (2-D) confined jet thrust vector control (CJTVC) nozzles was performed. The effects of adding secondary injection ports and changing exit height and secondary injection port...

T. M. Hawkes

1991-01-01

35

Experimental Study of an Axisymmetric Dual Throat Fluidic Thrust Vectoring Nozzle for Supersonic Aircraft Application.  

National Technical Information Service (NTIS)

An axisymmetric version of the Dual Throat Nozzle concept with a variable expansion ratio has been studied to determine the impacts on thrust vectoring and nozzle performance. The nozzle design, applicable to a supersonic aircraft, was guided using the un...

B. L. Berrier J. D. Flamm K. A. Deere M. L. Mason S. K. Johnson

2007-01-01

36

Fluidic Thrust Vectoring of an Axisymmetric Exhaust Nozzle at Static Conditions.  

National Technical Information Service (NTIS)

A sub-scale experimental static investigation of an axisymmetric nozzle with fluidic injection for thrust vectoring was conducted at the NASA Langley Jet Exit Test Facility. Fluidic injection was introduced through flush-mounted injection ports in the div...

D. J. Wing V. J. Giuliano

1987-01-01

37

A three-axis vibration isolation system using modified zero-power controller with parallel mechanism technique  

Microsoft Academic Search

This paper proposes a module-type three-degree-of-freedom vibration isolation system using modified zero-power control. Three vibration isolation modules are connected together using parallel mechanism to control 3-DOF motions. Each module consists of a common base, an individual middle mass and a common isolation table. The base to the middle mass is suspended by positive springs generated by active and passive system,

Takeshi Mizuno; Yuji Ishino; Masaya Takasaki

2011-01-01

38

Numerical investigation of thrust vectoring by injection of secondary air into nozzle flows  

NASA Astrophysics Data System (ADS)

Injection of secondary air into nozzle flows is an efficient method to control the thrust vector angle of an aircraft. A numerical investigation of thrust vectoring has been carried out for hypersonic aircraft in the transonic flight regime. In this speed range, single duct asymmetrical single expansion ramp nozzles operate far off design due to large nozzle exit areas required for optimal thrust coefficients at hypersonic cruise Mach numbers, thus producing large thrust components in the downward direction. Injecting secondary air into the nozzle flow in the critical transonic flight Mach number regime can lead to favorable gross thrust vector angles and thus improved thrust efficiency in flight direction. For a hypersonic aircraft's rectangular convergent-divergent nozzle configuration with a single expansion ramp, two dimensional Euler calculations of the complete afterbody flow field were carried out in the transonic flight regime, investigating subsonic as well as supersonic injection of the aircraft's forebody boundary layer air into the nozzle flow. Subsonic flow of the injected air along the expansion ramp produces a favorable pressure distribution on the ramp and results in advantageous thrust vectors with small force components normal to the flight direction and in best thrust efficiency. The interaction between the external flow, the jet plume flow, and the secondary air flow, as well as the behavior of the thrust vector, due to pressure and temperature variations of the injected forebody boundary layer air, are discussed. Also investigated was the impact of the aircraft's angle of attack on the complete nozzle flow field.

Berens, T.

1993-11-01

39

Performance Characteristics of Two Multiaxis Thrust-Vectoring Nozzles at Mach Numbers Up to 1.28.  

National Technical Information Service (NTIS)

The thrust-vectoring axisymmetric (VA) nozzle and a spherical convergent flap (SCF) thrust-vectoring nozzle were tested along with a baseline nonvectoring axisymmetric (NVA) nozzle in the Langley 16-Foot Transonic Tunnel at Mach numbers from 0 to 1.28 and...

D. J. Wing F. J. Capone

1993-01-01

40

Trajectory tracking control for the planar dynamics of a thrust vectored airship  

Microsoft Academic Search

This paper addresses and solves the trajectory tracking problem for the planar dynamics of a thrust vectored airship. The proposed controller is based on a combination of two nonlinear control design techniques, backstepping and exact tracking error dynamics passive output feedback (ETDPOF). Numerical simulations show the performance of the proposed controller and some concluding remarks complete the paper.

G. Murguia-Rendon; H. Rodriguez-Cortes; M. Velasco-Villa

2009-01-01

41

High Thrust to Weight Bipropellant Reentry Vehicle Thrust Vector Control Thru Micro-Miniaturization.  

National Technical Information Service (NTIS)

With the advent of nanosat and picosat-size satellites, the design of miniature, efficient, high thrust-to-weight (T/W) ratio thrust vector control (TVC) thrusters with liquid bipropellants has been evolving. The extremely high T/W ratios achievable with ...

W. Figueiredo

2003-01-01

42

Simultaneous thrust vector control and vibration isolation of satellites using steerable smart platforms  

Microsoft Academic Search

This paper presents an innovative concept, control strategies and experimental verification of simultaneous thrust vector control and vibration isolation of satellites. First, the innovative concept is introduced by employing a smart platform as an active structural interface between the main thruster of a satellite and the satellite structure. Second, the inverse kinematics and singularity analysis of the smart platform are

Mehrdad N. Ghasemi-Nejhad; Kougen Ma

2010-01-01

43

EXPERIMENTAL STUDY OF A NOZZLE USING FLUIDIC COUNTERFLOW FOR THRUST VECTORING  

Microsoft Academic Search

A static experimental investigation of a counterflow thrust vectoring nozzle concept was performed. The study was conducted in the NASA Langley Research Center Jet Exit Test Facility. Internal performance characteristics were defined over a nozzle pressure ratio (jet total to ambient) range of 3.5 to 10.0. The effects of suction collar geometry and suction slot height on nozzle performance were

Jeffrey D. Flamm

1998-01-01

44

Computational Study of a New Dual Throat Fluidic Thrust Vectoring Nozzle Concept.  

National Technical Information Service (NTIS)

A computational investigation of a two-dimensional nozzle was completed to assess the use of fluidic injection to manipulate flow separation and cause thrust vectoring of the primary jet thrust. The nozzle was designed with a recessed cavity to enhance th...

K. A. Deere B. L. Berrier J. D. Flamm S. K. Johnson

2005-01-01

45

An experimental investigation of active control of thrust vectoring nozzle flow fields  

NASA Astrophysics Data System (ADS)

Fluidic thrust vector control is examined in a supersonic rectangular jet having a 4:1 aspect ratio. Experiments conducted at a Mach number of 2 reveal that the thrust vector angle of the jet can be continuously varied by up to at least 16 deg by applying a counterflowing stream to one of the primary jet shear layers. A technique using counterflow eliminates the bistable response known to plague fluidic elements and is shown to be effective in both hot and cold supersonic jets. Results are presented for jet stagnation temperatures between 300 K and 670 K. Measurements indicate that the thrust vector control is both efficient as well as a linear function of the static pressure developed in the counterflowing stream. The typical power required to vector the jet at 16 degrees was estimated to be less than 1 percent of the power developed in the primary jet. Thrust vector control employing counterflow has several advantages over current technologies, the most important of which is the elimination of movable control surfaces which add considerable weight to the aircraft.

Strykowski, P. J.; Krothapalli, A.

1994-01-01

46

Development and qualification of a STAR 48 rocket motor with thrust vector control  

Microsoft Academic Search

A thrust vector control (TVC) nozzle for use on the STAR 48 rocket motor (STAR 48V) has been developed for use on the COMET program aboard the Conestoga launch vehicle. The first stages of qualification testing have been completed. The first STAR 48V has been successfully static-tested. The flexseal TVC nozzle design is based upon the qualified and flight-proven fixed

R. Hamke; J. Rade; R. Weldin

1992-01-01

47

FLUIDIC THRUST VECTORING OF AN AXISYMMETRIC EXHAUST NOZZLE AT STATIC CONDITIONS  

Microsoft Academic Search

A sub-scale experimental static investigation of an axisymmetric nozzle with fluidic injection for thrust vectoring was conducted at the NASA Langley Jet Exit Test Facility. Fluidic injection was introduced through flush-mounted injection ports in the divergent section. Geometric variables included injection-port geometry and location. Test conditions included a range of nozzle pressure ratios from 2 to 10 and a range

David J. Wing; Victor J. Giuliano

48

Development and test of electromechanical actuators for thrust vector control  

Microsoft Academic Search

A road map of milestones toward the goal of a full scale Redesigned Solid Rocket Motor\\/Flight Support Motor (RSRM\\/FSM) hot fire test is discussed. These milestones include: component feasibility, full power system demonstration, SSME hot fire tests, and RSRM hot fire tests. The participation of the Marshall Space Flight Center is emphasized.

Rae A. Weir; John R. Cowan

1993-01-01

49

Experimental and Computational Investigation of Multiple Injection Ports in a Convergent-Divergent Nozzle for Fluidic Thrust Vectoring.  

National Technical Information Service (NTIS)

A computational and experimental study was conducted to investigate the effects of multiple injection ports in a two-dimensional, convergent-divergent nozzle, for fluidic thrust vectoring. The concept of multiple injection ports was conceived to enhance t...

K. A. Waithe K. A. Deere

2003-01-01

50

Simulation of Thrust-Vectored Aircraft Maneuvers on a Human Centrifuge: Model Validation and Design for the Dynamic Environment Simulator.  

National Technical Information Service (NTIS)

This SBIR 2 final report covers three areas: (1) current state of the art of the human factors effects of flying thrust vectored, or supermaneuverable, aircraft, (2) the development and validation of a model of the 3 axis Dynamic Environment Simulator (DE...

J. A. VAN Poppel B. J. Barton D. J. Pancratz M. H. Rangel R. D. Banks

1998-01-01

51

Feedback control for counterflow thrust vectoring with a turbine engine: Experiment design and robust control design and implementation  

Microsoft Academic Search

Engineering research over the last few years has successfully demonstrated the potential of thrust vector control using counterflow at conditions up to Mach 2. Flow configurations that include the pitch vectoring of rectangular jets and multi-axis vector control in diamond and axisymmetric nozzle geometries have been studied. Although bistable (on-off) fluid-based control has been around for some time, the present

Delfim Zambujo Das Dores

2005-01-01

52

Three-axis particle impact probe  

DOEpatents

Three-axis particle impact probes detect particle impact vectors along x-, y-, and z-axes by means of a head mounted on the outer end of a shaft that is flexibly mounted in silicone rubber at the top of a housing so as to enable motion imparted to the head upon impact to be transmitted to a grounded electrode secured to the shaft within the housing. Excitable electrodes are mounted in the housing in a fixed position, spaced apart from the ground electrode and forming, with the ground electrode, capacitor pairs. Movement of the ground electrode results in changes in capacitance, and these differences in capacitance are used for measurement or derivation of momentum vectors along each of the three axes. In one embodiment, the ground electrode is mounted at the base of the shaft and is secured to a silicone rubber layer at the top of the housing, providing for cantilevered movement. In another embodiment, the shaft is mounted at its mid point in a flexible bushing so that it undergoes pivotal movement around that point.

Fasching, G.E.; Smith, N.S. Jr.; Utt, C.E.

1991-04-02

53

Three-axis particle impact probe  

DOEpatents

Three-axis particle impact probes detect particle impact vectors along x-, y-, and z-axes by spherical probe head mounted on the outer end of a shaft that is flexibly mounted in silicone rubber at the top of a housing so as to enable motion imparted to the head upon impact to be transmitted to a grounded electrode secured to the shaft within the housing. Excitable electrodes are mounted in the housing in a fixed position, spaced apart from the ground electrode and forming, with the ground electrode, capacitor pairs. Movement of the ground electrode results in changes in capacitance, and these difference in capacitance are used for measurement or derivation of momentum vectors along each of the three axes. In one embodiment, the ground electrode is mounted at the base of the shaft and is secured to a silicone rubber layer at the top of the housing, providing for cantilevered movement. In another embodiment, the shaft is mounted at its mid point in a flexible bushing so that it undergoes pivotal movement around that point.

Fasching, George E. (Morgantown, WV); Smith, Jr., Nelson S. (Morgantown, WV); Utt, Carroll E. (Morgantown, WV)

1992-01-01

54

Stable three-axis nuclear-spin gyroscope in diamond  

NASA Astrophysics Data System (ADS)

Gyroscopes find wide applications in everyday life from navigation and inertial sensing to rotation sensors in hand-held devices and automobiles. Current devices, based on either atomic or solid-state systems, impose a choice between long-time stability and high sensitivity in a miniaturized system. Here, we introduce a quantum sensor that overcomes these limitations by providing a sensitive and stable three-axis gyroscope in the solid state. We achieve high sensitivity by exploiting the long coherence time of the 14N nuclear spin associated with the nitrogen-vacancy center in diamond, combined with the efficient polarization and measurement of its electronic spin. Although the gyroscope is based on a simple Ramsey interferometry scheme, we use coherent control of the quantum sensor to improve its coherence time and robustness against long-time drifts. Such a sensor can achieve a sensitivity of ?˜0.5(mdegs-1)/Hzmm3 while offering enhanced stability in a small footprint. In addition, we exploit the four axes of delocalization of the nitrogen-vacancy center to measure not only the rate of rotation, but also its direction, thus obtaining a compact three-axis gyroscope.

Ajoy, Ashok; Cappellaro, Paola

2012-12-01

55

Three-Axis Acceleration Sensor Using Polyurea Films  

NASA Astrophysics Data System (ADS)

Focusing on the possibilities of polyurea as an acceleration sensor with characteristics such as flexibility, durability against large deformation, good linearity, and capability of deposition in dryprocess and insolubility in organic solvent, we first fabricated a cantilever acceleration sensor and a three-axis acceleration sensor. The output voltage in the large-strain region is measured using a polyurea cantilever sensor attached to a beryllium copper substrate. The results show that output voltages have good linearity for large strains up to 1%. This value is much larger than the breakdown limit of lead zirconate titanate. Second, we fabricated a polyurea three-axis acceleration sensor. The sensor consists of an insulation layer of polyurea on the cross beam substrate of phosphor bronze, a bottom aluminum electrode, a polyurea active layer, and four top aluminum electrodes. The experimental results for harmonic acceleration show that the sensor works as expected. The cross-axis sensitivity of the polyurea sensor was less than 8%, which is close to that of conventional microelectromechanical system sensors.

Tabaru, Masaya; Nakazawa, Marie; Nakamura, Kentaro; Ueha, Sadayuki

2008-05-01

56

Implicit time-marching solution of the Navier-Stokes equations for thrust reversing and thrust vectoring nozzle flows  

NASA Astrophysics Data System (ADS)

An implicit finite volume method is investigated for the solution of the compressible Navier-Stokes equations for flows within thrust reversing and thrust vectoring nozzles. Thrust reversing nozzles typically have sharp corners, and the rapid expansion and large turning angles near these corners are shown to cause unacceptable time step restrictions when conventional approximate factorization methods are used. In this investigation these limitations are overcome by using second-order upwind differencing and line Gauss-Siedel relaxation. This method is implemented with a zonal mesh so that flows through complex nozzle geometries may be efficiently calculated. Results are presented for five nozzle configurations including two with time varying geometries. Three cases are compared with available experimental data and the results are generally acceptable.

Imlay, S. T.

1986-11-01

57

Estimated optimum control of a spacecraft by the rocket engine thrust vector at the extraatmospheric section of the reentry of an artificial earth satellite  

Microsoft Academic Search

The paper investigates optimal, minimum-fuel control of a spacecraft by the rocket engine thrust vector on the extraatmospheric section of the reentry of a satellite. The control design, which provides for firing of the engine twice, is shown to be highly efficient. A high-speed algorithm is developed for calculating the estimated optimum reentry trajectories to the prescribed area of the

N. L. Sokolov; A. P. Sokolov; T. Iu. Smirnova

1992-01-01

58

A Three Axis Magnetometer For use in a Small Satellite  

Microsoft Academic Search

This paper deals with a construction of a three axis magnetometer for use in a small satellite. It is necessary to know the magnetic field around the satellite for an attitude stabilisation and for propulsion. A minimal weight, size and power consumption are the most critical properties of this construction. The magnetic flux has to be measured in an 8-bit

Linhart Richard

2006-01-01

59

Calibration of three-axis magnetometers with differential evolution algorithm  

NASA Astrophysics Data System (ADS)

The accuracy of three-axis magnetometers is influenced by different scale and bias of each axis and nonorthogonality between axes. One limitation of traditional iteration methods is that initial parameters influence the calibration, thus leading to the local optimal or wrong results. In this paper, a new method is proposed to calibrate three-axis magnetometers. To employ this method, a nonmagnetic rotation platform, a proton magnetometer, a DM-050 three-axis magnetometer and the differential evolution (DE) algorithm are used. The performance of this calibration method is analyzed with simulation and experiment. In simulation, the calibration results of DE, unscented Kalman filter (UKF), recursive least squares (RLS) and genetic algorithm (GA) are compared. RMS error using DE is least, which is reduced from 81.233 nT to 1.567 nT. Experimental results show that comparing with UKF, RLS and GA, the DE algorithm has not only the least calibration error but also the best robustness. After calibration, RMS error is reduced from 68.914 nT to 2.919 nT. In addition, the DE algorithm is not sensitive to initial parameters, which is an important advantage compared with traditional iteration algorithms. The proposed algorithm can avoid the troublesome procedure to select suitable initial parameters, thus it can improve the calibration performance of three-axis magnetometers.

Pang, Hongfeng; Zhang, Qi; Wang, Wei; Wang, Junya; Li, Ji; Luo, Shitu; Wan, Chengbiao; Chen, Dixiang; Pan, Mengchun; Luo, Feilu

2013-11-01

60

Attitude determination of small spinning spacecraft using three axis magnetometer and solar panels data  

Microsoft Academic Search

An algorithm for attitude determination of a spinning spacecraft in Low Earth Orbit using three axis magnetometer and solar panels data is proposed. With this algorithm, the solar panels necessary for power generation are also used as a sensing system for attitude determination. The algorithm employs voltage, current and temperature measurements from all of the solar panels to reconstruct the

F. Santoni; F. Bolotti

2000-01-01

61

A Micropower Front End for Three-Axis Capacitive Microaccelerometers  

Microsoft Academic Search

This paper presents the measurement results of a micropower switched-capacitor front end that was designed for three-axis capacitive microaccelerometers. The designed front end can reduce the distorting effects of the electrostatic forces and can be used in single-ended and differential modes. The front end was realized with a 0.13-mum bipolar complimentary metal-oxide-semiconductor process. The silicon area of the front end

Mika Kamarainen; Mikko Saukoski; Matti Paavola; Jere A. M. Jarvinen; Mika Laiho; Kari A. I. Halonen

2009-01-01

62

Summary of Fluidic Thrust Vectoring Research Conducted at NASA Langley Research Center.  

National Technical Information Service (NTIS)

Interest in low-observable aircraft and in lowering an aircraft's exhaust system weight sparked decades of research for fixed geometry exhaust nozzles. The desire for such integrated exhaust nozzles was the catalyst for new fluidic control techniques; inc...

K. A. Deere

2003-01-01

63

Dynamic model reduction of a flexible three-axis milling machine  

Microsoft Academic Search

The present paper discusses the numerical condensation of a finite element model of a three-axis high speed milling machine to a low-order state-space model suitable for control system design. The proposed reduction method forms an essential part of a Virtual Engineering environment for the design of a large class of mechatronic systems. In order to analyse the dynamic characteristics of

P. De Fonseca; D. Vandepitte; H. Van Brussel; P. Sas

64

Low-cost ultraviolet three-axis attitude sensor system  

Microsoft Academic Search

It is becoming increasingly obvious that satellite bus technologies that have been developed for traditional larger satellite platforms are not always suitable for use with smallsats. This is due to the intrinsic smallsat limitations in size, weight, available power, and cost. The problem is particularly obvious for attitude reference sensors of both the earth and star viewing type. In response

Douglas B. Pledger; James Billing-Ross; Ralph H. Castain; William W. Saylor

1993-01-01

65

Microfabrication of Three-Axis Tactile Feedback Actuator for Robot-Assisted Surgery  

NASA Astrophysics Data System (ADS)

In this paper, we propose and demonstrate a three-axis tactile feedback actuator using pneumatic balloons for human perception applications such as robot-assisted surgery systems. A tactile actuator is composed of a center structure having four balloons, sidewalls with one lateral balloon on each sidewall, and a bottom structure supporting the center structure. We fabricated the proposed device using flexible poly(dimethylsiloxane) and hard polyurethane with final dimensions of 18 × 18 × 18 mm3. The four balloons on the center structure produce normal tactile display during pneumatic-pressure-assisted inflation. The lateral movement of the center structure driven by sidewall balloons generates a shear tactile display on fingertips. The center deflections of the circular and rectangular balloons were calculated and measured experimentally.

Doh, Eunhyup; Yoo, Jihyung; Lee, Hyungkew; Park, Joonah; Yun, Kwang-Seok

2013-01-01

66

Design and fabriacation of a three-axis multilayer gradient coil for magnetic resonance microscopy of mice  

Microsoft Academic Search

There is great interest in the non-destructive capabilities of magnetic resonance microscopy for studying murine models of\\u000a both disease and normal function; however, these studies place extreme demands on the MR hardware, most notably the gradient\\u000a field system. We designed, using constrained current minimum inductance methods. and fabricated a complete, unshielded three-axis\\u000a gradient coil set that utilizes interleaved, multilayer axes

Blaine Chronik; Andrew Alejski; Brian K. Rutt

2000-01-01

67

A Monolithic Multisensor for three-axis Acccelerometer, Absolute pressure and Temperature  

Microsoft Academic Search

A monolithic multi-sensor for use in the severe environments is presented in the paper. This monolithic multi-sensor is realized by using (100) SOI wafer, which consists of a three-axis piezoresistive accelerometer, a piezoresistive absolute pressure sensor and a silicon thermistor temperature sensor. The three-axis accelerometer has been designed with four silicon beams to support the mass. The appropriate piezoresistor arrangement

Xu Jingbo; Zhao Yulong; Jiang Zhuangde; Sun Jian

2006-01-01

68

Three-dimensional plasma measurements from three-axis stabilized spacecraft  

SciTech Connect

Future planetary missions require that comprehensive three-dimensional measurements of electrons and mass-resolved ions be made from three-axis stabilized spacecraft. In order to make these measurements without requiring expensive and resource intensive platforms to scan space mechanically, we are developing various systems that are designed to scan space electrostatically. These systems also make it possible to circumvent the significant shadowing that would be present even with a scan platform, caused by necessary spacecraft appendages such as communications antennas and a power source (RTG or solar cell panels). The systems, which are axially symmetric, select particles arriving from 360/degree/ in azimuth along conical surfaces whose polar (or elevation) angles, referenced to the instrument symmetry axes, are determined by applying suitable deflection voltages to shapes deflectors. Particles thus selected in polar angle pass into spherically or toroidally-shaped electrostatic analyzers. After analysis, the 360/degree/ outputs of the analyzers are divided into discrete angular swaths to provide azimuthal angle resolution. In the case of electrons, the analyzed particles can be detected directly; in the case of ions, the particles in each swath can be counted directly, or further analyzed with time-of-flight or magnetic analyzers to obtain the velocity distributions of the separated major ion constituents. We present computer simulations of particle paths through the various analyzers of this type and show results from laboratory calibrations of prototypes.

Bame, S.J.; Martin, R.H.; McComas, D.J.; Burch, J.L.; Marshall, J.A.; Young, D.T.

1988-01-01

69

The Development of a Pseudo-Nyquist Analysis Technique for Hybrid Sampled-Data Control Systems.  

National Technical Information Service (NTIS)

The stability characteristics of a launch vehicle, as a function of gain and phase variations at the thrust vector controller, cannot be obtained using classical sampled-data control theory if the launch vehicle attitude control system contains both sampl...

C. W. Davis M. G. Burnitt

1973-01-01

70

Development of a biped walking robot compensating for three-axis moment by trunk motion  

Microsoft Academic Search

The authors have been using the ZMP (zero moment point) as a criterion to distinguish the stability of walking for a biped walking robot which has a trunk. The authors introduce a control method of dynamic biped walking for a biped walking robot to compensate for the three-axis (pitch, roll and yaw-axis) moment on an arbitrary planned ZMP by trunk

Jin-ichi YAMAGUCHI; Atsuo TAKANISHI; I. Kato

1993-01-01

71

Double Gimballed Momentum Wheel for Precision Three-Axis Attitude Control.  

National Technical Information Service (NTIS)

For precision three-axis attitude control of space vehicles, a Doubled Gimballed Momentum Wheel (DGMW) as attitude actuator is a favorable approach. A high reliability DGMW of modular design with two momentum wheels and two direct drive ultra high resolut...

W. Auer

1984-01-01

72

Gait analyzer based on a cell phone with a single three-axis accelerometer  

Microsoft Academic Search

We propose a fuss-free gait analyzer based on a single three- axis accelerometer mounted on a cell phone for health care and presence services. It is not necessary for users not to wear sensors on any part of their bodies; all they need to do is to carry the cell phone. Our algorithm has two main functions; one is to

Toshiki Iso; Kenichi Yamazaki

2006-01-01

73

Three-axis magnetic flux leakage in-line inspection simulation based on finite-element analysis  

NASA Astrophysics Data System (ADS)

With the increase of pipelines, corrosion leakage accidents happen frequently. Therefore, nondestructive testing technology is important for ensuring the safe operation of the pipelines and energy mining. In this paper, the structure and principle of magnetic flux leakage (MFL) in-line inspection system is introduced first. Besides, a mathematic model of the system according to the ampere circuit rule, flux continuity theorem, and column coordinate transform is built, and the magnetic flux density in every point of space is calculated based on the theory of finite element analysis. Then we analyze and design the disposition of measurement section probes and sensors combining both three-axis MFL in-line inspection and multi-sensor fusion technology. Its advantage is that the three-axis changes of magnetic flux leakage field are measured by the multi-probes at the same time, so we can determine various defects accurately. Finally, the theory of finite element analysis is used to build a finite element simulation model, and the relationship between defects and MFL inspection signals is studied. Simulation and experiment results verify that the method not only enhances the detection ability to different types of defects but also improves the precision and reliability of the inspection system.

Feng, Jian; Zhang, Jun-Feng; Lu, Sen-Xiang; Wang, Hong-Yang; Ma, Rui-Ze

2013-01-01

74

A novel three-axis force sensor for advanced training of shot-put athletes  

Microsoft Academic Search

This paper presents a novel three-axis force sensor for measuring the throwing forces of shot-put athletes. The shot-put sensor has been designed and fabricated with almost the same size and weight as the standard shot for open males. Instead of using a common shot, the shot-putters can use this shot-put sensor to make their throws. The sensor can simultaneously detect

Guangming Song; Hongyan Yuan; Yi Tang; Quanjun Song; Yunjian Ge

2006-01-01

75

A novel three-axis AIM vibration sensor for high accuracy condition monitoring  

Microsoft Academic Search

We present a novel micromachining approach for on chip three-axis capacitive high aspect ratio acceleration sensors made from standard silicon wafers. The patented AIM (air gap insulated microstructures) technology with their excellent device properties regarding temperature behavior, capacitive sensitivity and reliability was modified for enabling out-of-plane differential measurements. Therefore electrodes with different heights have been patterned by using one additional

Markus Nowack; Danny Reuter; Andreas Bertz; Matthias Kuechler; Torsten Aurich; Claus Dittrich; T. Gessner

2010-01-01

76

A bulk-micromachined three-axis accelerometer using silicon direct bonding technology and polysilicon layer  

Microsoft Academic Search

A three-axis piezoresistive acceleroraeter has been fabricated by bulk-micromachining and SDB (silicon direct bonding) technologies using a polysilicon layer. The results of FEM (finite-element method) simulation for each acceleration direction have been utilized to detect the three-dimensional acceleration and eliminate cross-axis sensitivities. The relative changes of resistance as a function of temperature in LPCVD polysilicon layers with boron implantation dose

Kijin Kwon

1998-01-01

77

Development of an ion energy mass spectrometer for application on board three-axis stabilized spacecraft  

SciTech Connect

We have developed an ion energy mass spectrometer for use aboard three-axis stabilized spacecraft. This spectrometer measures the three-dimensional distribution function of mass-discriminated ions with a high sampling rate using electrostatic energy analysis and time-of-flight mass analysis. Three-axis stabilized spacecraft make it difficult to obtain complete coverage of all possible plasma arrival directions. We have added angular scanning deflectors to a cylindrically symmetric analyzer to provide a hemispherical (2{pi} str) field of view. Ion analyzers need suitable sensitivity with respect to surrounding space plasma fluxes, whose intensities vary greatly depending especially on plasma regions such as the solar wind and the planetary magnetospheres. To obtain a wide range of sensitivity, we equipped the analyzer with sensitivity control electrodes. Ions originating from planetary atmosphere and surface include various ion species such as Na{sup +}, Mg{sup +}, Al{sup +}, and Fe{sup +}. The time-of-flight device of our spectrometer applies a peculiar electric field, called a linear electric field, which increases linearly with the penetration length of incident ions to enable mass resolution higher than that of conventional time-of-flight techniques. In this electric field, ions bounce in simple harmonic motion, where the energy and flight path no longer affect the flight time and thus the mass resolution. We have designed and fabricated the ion energy mass spectrometer, and have evaluated its performance through laboratory experiments.

Yokota, Shoichiro; Saito, Yoshifumi; Asamura, Kazushi; Mukai, Toshifumi [Institute of Space and Astronautical Science, Kanagawa 229-8510 (Japan)

2005-01-01

78

An Experimental Optical Three-axis Tactile Sensor Featured with Hemispherical Surface  

NASA Astrophysics Data System (ADS)

We are developing an optical three-axis tactile sensor capable of acquiring normal and shearing force to mount on a robotic finger. The tactile sensor is based on the principle of an optical waveguide-type tactile sensor, which is composed of an acrylic hemispherical dome, a light source, an array of rubber sensing elements, and a CCD camera. The sensing element of the silicone rubber comprises one columnar feeler and eight conical feelers. The contact areas of the conical feelers, which maintain contact with the acrylic dome, detect the three-axis force applied to the tip of the sensing element. Normal and shearing forces are then calculated from integration and centroid displacement of the grayscale value derived from the conical feeler's contacts. To evaluate the present tactile sensor, we conducted a series of experiments using an x-z stage, a rotational stage, and a force gauge. Although we discovered that the relationship between the integrated grayscale value and normal force depends on the sensor's latitude on the hemispherical surface, it is easy to modify the sensitivity based on the latitude to make the centroid displacement of the grayscale value proportional to the shearing force. When we examined the repeatability of the present tactile sensor with 1,000 load/unload cycles, the error was 2%.

Ohka, Masahiro; Kobayashi, Hiroaki; Takata, Jumpei; Mitsuya, Yasunaga

79

A Three-Axis Force Sensor for Dual Finger Haptic Interfaces  

PubMed Central

In this work we present the design process, the characterization and testing of a novel three-axis mechanical force sensor. This sensor is optimized for use in closed-loop force control of haptic devices with three degrees of freedom. In particular the sensor has been conceived for integration with a dual finger haptic interface that aims at simulating forces that occur during grasping and surface exploration. The sensing spring structure has been purposely designed in order to match force and layout specifications for the application. In this paper the design of the sensor is presented, starting from an analytic model that describes the characteristic matrix of the sensor. A procedure for designing an optimal overload protection mechanism is proposed. In the last part of the paper the authors describe the experimental characterization and the integrated test on a haptic hand exoskeleton showing the improvements in the controller performances provided by the inclusion of the force sensor.

Fontana, Marco; Marcheschi, Simone; Salsedo, Fabio; Bergamasco, Massimo

2012-01-01

80

Intracalibration of particle detectors on a three-axis stabilized geostationary platform  

NASA Astrophysics Data System (ADS)

We describe an algorithm for intracalibration of measurements from plasma or energetic particle detectors on a three-axis stabilized platform. Modeling and forecasting of Earth's radiation belt environment requires data from particle instruments, and these data depend on measurements which have an inherent calibration uncertainty. Pre-launch calibration is typically performed, but on-orbit changes in the instrument often necessitate adjustment of calibration parameters to mitigate the effect of these changes on the measurements. On-orbit calibration practices for particle detectors aboard spin-stabilized spacecraft are well established. Three-axis stabilized platforms, however, pose unique challenges even when comparisons are being performed between multiple telescopes measuring the same energy ranges aboard the same satellite. This algorithm identifies time intervals when different telescopes are measuring particles with the same pitch angles. These measurements are used to compute scale factors which can be multiplied by the pre-launch geometric factor to correct any changes. The approach is first tested using measurements from GOES-13 MAGED particle detectors over a 5-month time period in 2010. We find statistically significant variations which are generally on the order of 5% or less. These results do not appear to be dependent on Poisson statistics nor upon whether a dead time correction was performed. When applied to data from a 5-month interval in 2011, one telescope shows a 10% shift from the 2010 scale factors. This technique has potential for operational use to help maintain relative calibration between multiple telescopes aboard a single satellite. It should also be extensible to inter-calibration between multiple satellites.

Rowland, W.; Weigel, R. S.

2012-11-01

81

Simulation and experimental study of a three-axis fiber Bragg grating accelerometer based on the pull–push mechanism  

NASA Astrophysics Data System (ADS)

A three-axis fiber Bragg grating accelerometer, which has uniform sensitivities to three axes, has been developed for seismic application. This paper presents the design, simulation and calibration of the three-axis accelerometer. A series of experiments were performed to measure harmonic vibration and shock vibration. The precise acceleration was measured by a PZT accelerometer which provided high sensitivity. The fully described dynamic sensitivity of three-axis accelerometers represented by a 3-by-3 matrix is given. The results indicate that the accelerometer has a sensitivity of 0.068 V g?1 in a measured full scale of ±2.5 m s?2. The cross-axis sensitivity was measured as ?75.5 dB, ?75.5 dB and ?78.2 dB, respectively.

Jiang, Qi; Yang, Meng

2013-11-01

82

Thrust vector control control using internal airfoils  

SciTech Connect

This patent describes an exhaust nozzle for an engine which generates thrust expulsion of gaseous products of fuel combustion. It comprises: a generally axisymmetric housing defined along a central thrust axis including a wall structure defining an exhaust duct, and axially adjacent radially inwardly converging portion, throat portion and radially outwardly diverging portion; and at least one airfoil sized to protrude into the exhaust a distance corresponding to about 15 to 35 percent of diameter of the throat portion disposed within the divergent portion at a location axially spaced from the axis portion a distance corresponding to from 20 per cent to 25 per cent of the axial extent of the divergent portion, the airfoil mounted on the wall structure for rotation about an axis substantially perpendicular to the thrust axis.

Herup, E.J.; Franke, M.E.; Friddell, J.H.

1992-10-13

83

Computational Investigation of Fluidic Counterflow Thrust Vectoring  

Microsoft Academic Search

A computational study of fluidic counterflow thrustvectoring has been conducted. Two-dimensionalnumerical simulations were run using the computationalfluid dynamics code PAB3D with two-equationturbulence closure and linear Reynolds stress modeling.For validation, computational results were compared toexperimental data obtained at the NASA Langley JetExit Test Facility. In general, computational resultswere in good agreement with experimental performancedata, indicating that efficient...

C. A. Hunter; K. A. Deere

1999-01-01

84

Plasma flow deflection systems created for space electric jet thrusters  

NASA Astrophysics Data System (ADS)

In this paper a long-term deflection system for the accelerator plasma flux control is considered. Such systems utilization will permit varying the thrust vector angle over a wide range under low energy expenditure (5-10 W/grade). As one of alternatives a focusing and defocusing system of the compensated ion flux was studied.

Avakimian, B. O.; Kolesnikov, A. V.

1992-08-01

85

Three-axis tactile display using PDMS pneumatic actuator for robot-assisted surgery  

Microsoft Academic Search

This paper proposes and demonstrates the 3-axis tactile display actuator using PDMS pneumatic balloons for a robot assisted surgery system. Inflated balloons on the upper surface generate normal forces to a fingertip. In addition, the lateral actuation by side balloons in 2-axis generate shear force to an operator. This operation is suitable for mounting on the operator’s fingers for normal

Eunhyup Doh; Hyungkew Lee; Kwang-Seok Yun

2011-01-01

86

Fluid slosh dynamics of surface tension tanks in three axis stabilized spacecraft  

NASA Astrophysics Data System (ADS)

A method for investigating propellant-tank interaction, satellite-tank interaction, and dynamic behavior of propellant in the tank is summarized. Sloshing with small and large amplitudes, and movement in bulks are considered. The ERNO MAUS tank experiment (EMTE) is described. The EMTE is a spaceborne experiment to study the dynamic behavior, orientation, and stability of liquids in tanks in reduced gravity. The sinusoidal excitation setup, and measurement and observation systems are outlined. Integration in a TEXUS rocket is illustrated.

Beig, H. G.; Hornung, E.

87

On the nonlinear problem of the three-axis reorientation of a three-rotor gyrostat in the game noise model  

NASA Astrophysics Data System (ADS)

The nonlinear game problem of the three-axis reorientation of an asymmetric solid body with three flywheels (rotors) has been solved. Acceptable levels of uncontrollable noise depending on given constraints of control moments have been estimated.

Vorotnikov, V. I.; Martyshenko, Yu. G.

2013-09-01

88

Integrated propulsion-based flight control system design for a civil transport aircraft  

Microsoft Academic Search

We describe results of a study carried out at the University of Leicester in collaboration with Volvo Aero Corporation, on the design of integrated flight and propulsion control systems for a large civil transport aircraft. The use of the aircraft engines (via differential thrust and\\/or thrust vectoring) for the purposes of emergency flight control is examined in detail. An industry

M. Harefors; D. G. Bates

2002-01-01

89

Three-axis attitude control of a small satellite by magnetic PD-like controller integrated with passive pitch bias momentum method  

Microsoft Academic Search

The attitude acquisition problem of a magnetic small satellite under effect of environmental disturbances is solved by two methods. The first method stabilizes the nonlinear attitude in three-axis by purely electromagnetic actuation. The second method exploits the inertial stiffness provided by a pitch momentum wheel to gain insensitivity to disturbances. The simulation results obtained for the same initial conditions show

Ahmet Sofyali; Elbrous M. Jafarov

2011-01-01

90

Three-axis acoustic device for levitation of droplets in an open gas stream and its application to examine sulfur dioxide absorption by water droplets  

NASA Astrophysics Data System (ADS)

Two acoustic devices to stabilize a droplet in an open gas stream (single-axis and three-axis levitators) have been designed and tested. The gas stream was provided by a jet apparatus with a 64 mm exit diameter and a uniform velocity profile. The acoustic source used was a Langevin vibrator with a concave reflector. The single-axis levitator relied primarily on the radial force from the acoustic field and was shown to be limited because of significant droplet wandering. The three-axis levitator relied on a combination of the axial and radial forces. The three-axis levitator was applied to examine droplet deformation and circulation and to investigate the uptake of SO2 from the gas stream to the droplet. Droplets ranging in diameters from 2 to 5 mm were levitated in gas streams with velocities up to 9 m/s. Droplet wandering was on the order of a half droplet diameter for a 3 mm diameter droplet. Droplet circulation ranged from the predicted Hadamard-Rybczynski pattern to a rotating droplet pattern. Droplet pH over a central volume of the droplet was measured by planar laser induced fluorescence. The results for the decay of droplet pH versus time are in general agreement with published theory and experiments.

Stephens, Terrance L.; Budwig, Ralph S.

2007-01-01

91

Three-axis acoustic device for levitation of droplets in an open gas stream and its application to examine sulfur dioxide absorption by water droplets.  

PubMed

Two acoustic devices to stabilize a droplet in an open gas stream (single-axis and three-axis levitators) have been designed and tested. The gas stream was provided by a jet apparatus with a 64 mm exit diameter and a uniform velocity profile. The acoustic source used was a Langevin vibrator with a concave reflector. The single-axis levitator relied primarily on the radial force from the acoustic field and was shown to be limited because of significant droplet wandering. The three-axis levitator relied on a combination of the axial and radial forces. The three-axis levitator was applied to examine droplet deformation and circulation and to investigate the uptake of SO(2) from the gas stream to the droplet. Droplets ranging in diameters from 2 to 5 mm were levitated in gas streams with velocities up to 9 ms. Droplet wandering was on the order of a half droplet diameter for a 3 mm diameter droplet. Droplet circulation ranged from the predicted Hadamard-Rybczynski pattern to a rotating droplet pattern. Droplet pH over a central volume of the droplet was measured by planar laser induced fluorescence. The results for the decay of droplet pH versus time are in general agreement with published theory and experiments. PMID:17503939

Stephens, Terrance L; Budwig, Ralph S

2007-01-01

92

A study of angular motion of the Chibis-M microsatellite with three-axis flywheel control  

NASA Astrophysics Data System (ADS)

We study the controlled angular motion of the Chibis-M microsatellite. Executive elements are three pairs of flywheels, whose axes are mutually perpendicular. The task of the control system is realization of a required program motion and support of its asymptotic stability. In this paper, we synthesize a control algorithm and study the evolution of the angular momentum of flywheels on long time intervals. The attitude accuracy is estimated for the case when disturbances act upon the spacecraft.

Ovchinnikov, M. Yu.; Tkachev, S. S.; Karpenko, S. O.

2012-11-01

93

In-flight system identification for the CRAF\\/Cassini spacecraft  

Microsoft Academic Search

The feasibility and payoffs of conducting in-flight system dynamics identification for the CRAFT\\/Cassini\\/(C\\/C) spacecraft are studied. The primary control modes of: (a) the boom-mounted high precision scan platform articulation\\/pointing control; and (b) the main engine thrust vector control are analyzed. Identification of key transfer functions and models and subsequent design of modern robust controllers by recently developed advanced processing algorithms

Edward Mettler; David S. Bayard; Yeung Yam; Robert E. Scheid

1992-01-01

94

Control of Ducted Fan Flying Object Using Thrust Vectoring  

NASA Astrophysics Data System (ADS)

Recently, R/C helicopter is used in fields of aerial photography and aerial investigation. But helicopter rotor blades are not covered, and the thrust is generated by high rotational speed. Thus R/C helicopter has a high risk of damage. In this study, we developed a new flying object using ducted fans instead of rotor blades. At first, PD control was employed for pitch and roll attitude control, but it caused steady state error. Moreover, PI-D control was used instead of PD control, and it reduced the steady state error. We succeeded to achieve stable hovering by 3-axes (roll, pitch and yaw axis) attitude control.

Miwa, Masafumi; Shigematsu, Yuki; Yamashita, Takashi

95

Advanced launch system (ALS) actuation and power systems impact operability and cost  

SciTech Connect

To obtain the advanced launch system (ALS) primary goals of reduced costs ($300/lb earth to LEO) and improved operability, there must be significant reductions in the launch operability, there must be significant reductions in the launch operations and servicing requirements relative to current vehicle designs and practices. One of the primary methods for achieving these goals is by using electrical actuation integrated with a single vehicle electrical power system and controls for all actuation and avionics requirements. This paper reviews the ALS and its associated advanced development program to demonstrate maturation of those technologies that will help meet the overall operability and cost goals. The electric power and actuation systems are highlighted as a specific technology ready not only to meet the ALS goals (cryogenic fuel valves and thrust vector controls with peak power demands to 75 hp), but also those of other launch vehicles, military and civilian aircraft, lunar/Martian vehicles and a multitude of commercial applications.

Sundberg, G.R. (National Aeronautics and Space Administration, Cleveland, OH (USA). Lewis Research Center)

1990-09-01

96

A quaternion-based initial orientation estimation system suitable for one special dynamic state Using low cost magnetometer and accelerometer  

Microsoft Academic Search

This work presents a new method for estimating the initial orientation of one micro air vehicle (MAV) whose navigation system is powered in a dynamic condition, using low cost three-axis magnetometer and three-axis accelerometer. Although the earth's magnetic field offers a steady reference vector to determine the attitude, only one vector is insufficient to get accurate values. To solve this

Chang Liu; Jie Li; Kewei Huang; Fei Liu

2012-01-01

97

Accelerometer System for Mapping Marine Sediment Instabilities.  

National Technical Information Service (NTIS)

A three axis accelerometer system has been developed to measure low amplitude offshore sediment motion and long term sediment shifts resulting in tilt of the implanted sensor. A significant property of this design allows extensive signal conditioning on t...

1978-01-01

98

Advanced solid rocket motor nozzle thrust vector control flexseal development status  

NASA Astrophysics Data System (ADS)

The advanced solid rocket motor (ASRM) flexseal development status is reviewed focusing on design goals and requirements, design configuration, analysis activities, and verification tests. It is concluded that the ASRM flexseal incorporates flight-proven materials in an innovative design configuration. Variable thickness shims and efficient packaging of the flexseal make it possible to achieve a significant weight reduction. A flexseal insulator design derived from strategic solid rocket motor experience will provide the necessary bearing thermal protection while minimizing vectoring torque variability.

Prins, William S.; Meyer, Scott A.; Cox, Paul D.

1992-07-01

99

High Thrust to Weight Bipropellant Reentry Vehicle Thrust Vector Control Thru Micro-Miniaturization.  

National Technical Information Service (NTIS)

These briefing charts represent a speech given by the author at the AIAA Joint Propulsion Conference held in Huntsville, Alabama, on 20-23 2003. The speech covered the following topics: the high thrust-to-weight ratios achievable through micro-miniaturiza...

B. Figueiredo

2003-01-01

100

Analysis and Design of an Attitude Control System for Non-Rigid Satellites.  

National Technical Information Service (NTIS)

A design process for three axis attitude control systems of flexible satellites using a double gimballed momentum wheel is given. The mathematical model was derived using overall structure eigenmodes, which leads to uncoupled transfer functions. The effec...

D. Poelaert A. Liegeois M. Dureigne

1973-01-01

101

Study of Attitude Control Systems Using the Earth's Magnetic Field at Synchronous Altitudes.  

National Technical Information Service (NTIS)

Those control functions, typical of spin stabilized and three axis stabilized momentum biased satellites that are suitable for implementation by magnetic control concepts, are discussed and detailed design of such control systems is presented including ha...

R. S. Harris

1978-01-01

102

Design of Power Electronics for TVC and EMA Systems.  

National Technical Information Service (NTIS)

The Component Development Division of the Propulsion Laboratory at Marshall Space Flight Center (MSFC) is currently developing a class of electromechanical actuators (EMA's) for use in space transportation applications such as thrust vector control (TVC) ...

R. M. Nelms J. B. Bell M. T. Shepherd

1994-01-01

103

Predicting performance of candidates to replace Halon 2402 (Freon 114B2) in the Minuteman III Second Stage LITVC system  

NASA Astrophysics Data System (ADS)

Halon 2402 is the liquid injectant currently used in the Liquid Injection Thrust Vector Control (LITVC) system of the Minuteman III Second Stage motor. A replacement for Halon is required which provides comparable performance in terms of maximum side force and total impulse without detrimental environmental effects. The search for a replacement requires identification of desired thermochemical properties and prediction of performance. The method and procedures used for prediction of injection performance are described. Results of tests performed on benchmark liquids and an initial list of possible injectants using the Walker-Shandor and CFD models are presented and compared. Results from future live motor tests will be compared with the present predictions and used to validate the approach taken to select and predict the performance of new LITVC fluids.

Glenn, D. E.

1992-07-01

104

Three-axis electron-beam test facility  

NASA Astrophysics Data System (ADS)

An electron beam test facility, which consists of a precision multidimensional manipulator built into an ultra-high-vacuum bell jar, was designed, fabricated, and operated at Lewis Research Center. The position within the bell jar of a Faraday cup which samples current in the electron beam under test, is controlled by the manipulator. Three orthogonal axes of motion are controlled by stepping motors driven by digital indexers, and the positions are displayed on electronic totalizers. In the transverse directions, the limits of travel are approximately + or - 2.5 cm from the center with a precision of 2.54 micron (0.0001 in.); in the axial direction, approximately 15.0 cm of travel are permitted with an accuracy of 12.7 micron (0.0005 in.). In addition, two manually operated motions are provided, the pitch and yaw of the Faraday cup with respect to the electron beam can be adjusted to within a few degrees. The current is sensed by pulse transformers and the data are processed by a dual channel box car averager with a digital output. The beam tester can be operated manually or it can be programmed for automated operation. In the automated mode, the beam tester is controlled by a microcomputer (installed at the test site) which communicates with a minicomputer at the central computing facility. The data are recorded and later processed by computer to obtain the desired graphical presentations.

Dayton, J. A., Jr.; Ebihara, B. T.

1981-03-01

105

Aircraft Ground Test and Subscale Model Results of Axial Thrust Loss Caused by Thrust Vectoring Using Turning Vanes.  

National Technical Information Service (NTIS)

The NASA-Dryden F/A-18 high alpha research vehicle was modified to incorporate three independently controlled turning vanes located aft of the primary nozzle of each engine to vector thrust for pitch and yaw control. Ground measured axial thrust losses we...

S. A. Johnson

1992-01-01

106

Personal Propulsion System.  

National Technical Information Service (NTIS)

The report describes a laboratory model of a simple manually controlled, tractor type, personnel propulsion unit for use under zero gravity conditions. The device consists of a pair of hand-mounted thrust nozzles with fore and aft thrust vector control. A...

G. E. Hanff R. H. Moulton R. E. Geller

1965-01-01

107

Solar Pointing Attitude Rocket Control System \\/SPARCS  

Microsoft Academic Search

The SPARCS system is described and its use since Dec. 1967 is reviewed. SPARCS was developed to fulfill a requirement for a lightweight, precision, three-axis pointing control system for solar-sounding rockets. The use of sounding rockets to calibrate satellite instruments before flight for subsequent recovery and orbital flight is noted, along with the calibration of Skylab instruments with sounding rocket

J. M. Shigemoto

1982-01-01

108

Magellan spacecraft thermal control system design and performance  

Microsoft Academic Search

A thermal control system of the Magellan spacecraft launched on May 4, 1989 to perform radar mapping and other science experiments is described. The thermal control system design required sustained operations near Venus in a three-axis stabilized spacecraft. It is concluded that, despite the constraints imposed by Magellan's thermal degradation, the primary mission goal of mapping at least 70 percent

James C. Neuman; Joseph A. Buescher; Gregory J. Esterl

1993-01-01

109

Design of power electronics for TVC EMA systems  

NASA Astrophysics Data System (ADS)

The Composite Development Division of the Propulsion Laboratory at Marshall Space Flight Center (MSFC) is currently developing a class of electromechanical actuators (EMA's) for use in space transportation applications such as thrust vector control (TVC) and propellant control valves (PCV). These high power servomechanisms will require rugged, reliable, and compact power electronic modules capable of modulating several hundred amperes of current at up to 270 volts. MSFC has selected the brushless dc motor for implementation in EMA's. This report presents the results of an investigation into the applicability of two new technologies, MOS-controlled thyristors (MCT's) and pulse density modulation (PDM), to the control of brushless dc motors in EMA systems. MCT's are new power semiconductor devices, which combine the high voltage and current capabilities of conventional thyristors and the low gate drive requirements of metal oxide semiconductor field effect transistors (MOSFET's). The commanded signals in a PDM system are synthesized using a series of sinusoidal pulses instead of a series of square pulses as in a pulse width modulation (PWM) system. A resonant dc link inverter is employed to generate the sinusoidal pulses in the PDM system. This inverter permits zero-voltage switching of all semiconductors which reduces switching losses and switching stresses. The objectives of this project are to develop and validate an analytical model of the MCT device when used in high power motor control applications and to design, fabricate, and test a prototype electronic circuit employing both MCT and PDM technology for controlling a brushless dc motor.

Nelms, R. Mark

1993-08-01

110

Critical engine system design characteristics for SSTO vehicles  

NASA Astrophysics Data System (ADS)

Engine system design characteristics are summarized for typical vertical take-off and landing (VTOL) and vertical take-off and horizontal landing (VTHL) Strategic Defense Initiative Organization (SDIO) single stage to orbit (SSTO) vehicles utilizing plug nozzle configurations. Power cycle selection trades involved the unique modular platelet engine (MPE) with the use of (1) LO2 and LH2 at fixed and variable mixture ratios, (2) LO2 and propane or RP-1, and (3) dual fuels (LO2 with LH2 and C3H8). The number of thrust cells and modules were optimized. Dual chamber bell and a cluster of conventional bell nozzle configurations were examined for comparison with the plug configuration. Thrust modulation (throttling) was selected for thrust vector control. Installed thrust ratings were established to provide an additional 20 percent overthrust capability for engine out operation. Turbopumps were designed to operate at subcritical speeds to facilitate a wide range of throttling and long life. A unique dual spool arrangement with hydrostatic bearings was selected for the LH2 turbopump. Controls and health monitoring with expert systems for diagnostics are critical subsystems to ensure minimum maintenance and supportability for a less than seven day turnaround. The use of an idle mode start, in conjunction with automated health condition monitoring, allows the rocket propulsion system to operate reliably in the manner of present day aircraft propulsion.

Fanciullo, Thomas J.; Judd, D. C.; Obrien, C. J.

1992-02-01

111

Transition of a technology base for advanced aircraft gas turbine control systems  

SciTech Connect

Technology assessments during the 1980s projected the development of advanced military fighter aircraft that would require propulsion systems that could accommodate multimission capability with super maneuverability. These propulsion systems would be required to provide significantly improved thrust to weight, reduced thrust specific fuel consumption, and up and away thrust vectoring capabilities. Digital electronic control systems with significantly expanded capabilities would be required to handle these multifunction control actuation systems, to integrate them with flight control systems, and to provide fail-operational capability. This paper will discuss the challenges that were presented to propulsion system control designers, the innovation of technology to address these challenges, and the transition of that technology to production readiness. Technology advancements will be discussed in the area of digital electronic control capability and packaging, advanced fuel management systems, high pressure fuel hydraulic actuation systems for multifunction nozzles, integrated flight propulsion controls, and higher-order language software development tools. Each of these areas provided unique opportunities where technology development programs and flight prototyping carried concepts to reality.

McGlone, M.E. [Pratt and Whitney, West Palm Beach, FL (United States)

1998-07-01

112

X-31 helmet-mounted visual and audio display (HMVAD) system  

NASA Astrophysics Data System (ADS)

Agile aircraft (X-29, X-31, F-18 High Alpha Research Vehicle and F-16 Multi-Axis Thrust Vector) test pilots, while flying at high angles of attack, experience difficulty predicting their flight path trajectory. To compensate for the loss of this critical element of situational awareness, the X-31 International Test Organization (ITO) installed and evaluated a helmet mounted display (HMD) system into an X-31 aircraft and simulator. Also investigated for incorporation within the HMD system and flight evaluation was another candidate technology for improving situational awareness -three dimensional audio. This was the first flight test evaluating the coupling of visual and audio cueing for aircrew aiding. The focus of the endeavor, which implemented two visual and audio formats, was to examine the extent visual and audio orientation cueing enhanced situational awareness and improved pilot performance during tactical flying. This paper provides an overview of the X-31 HMVAD system, describes the visual and audio symbology, presents a summary of the pilots' subjective evaluation of the system following its use in simulation and flight test, and outlines the future plans for the X-31 HMVAD system.

Boehmer, Steven C.

1994-06-01

113

Auxiliary lift propulsion system with oversized front fan  

SciTech Connect

A propulsion system for use primarily in V/STOL aircraft is provided with a variable cycle, double bypass gas turbofan engine and a remote augmenter to produce auxiliary lift. The fan is oversized in air-pumping capability with respect to the cruise flight requirements of the remainder of the engine and a variable area, low pressure turbine is capable of supplying varying amounts of rotational energy to the oversized fan, thereby modulating its speed and pumping capability. During powered lift flight, the variable cycle engine is operated in the single bypass mode with the oversized fan at its maximum pumping capability. In this mode, substantially all of the bypass flow is routed as an auxiliary airstream to the remote augmenter where it is mixed with fuel, burned and exhausted through a vectorable nozzle to produce thrust for lifting. Additional lift is generated by the high energy products of combustion of the variable cycle engine which are further energized in an afterburner and exhausted through a thrust vectorable nozzle at the rear of the engine.

Castells, O.T.; Johnson, J.E.; Rundell, D.J.

1980-09-16

114

The application of error quaternion and PID control method in Earth observation satellite's attitude control system  

Microsoft Academic Search

Because of its payload's work characteristic, it requires much higher precision in Earth observation satellite's attitude control systems than others. Most Earth observation satellites use zero-momentum three-axis stabilization control method. This paper investigates this control method in satellite control system, deducing the dynamics and kinematics of satellite attitude's model expressed by attitude error quaternion, applying PID control method in this

Qiyu Wang; Jianping Yuan; Zhanxia Zhu

2006-01-01

115

Study of attitude control systems using the earth's magnetic field at synchronous altitudes  

Microsoft Academic Search

Those control functions, typical of spin stabilized and three axis stabilized momentum biased satellites that are suitable for implementation by magnetic control concepts, are discussed and detailed design of such control systems is presented including hardware and interface requirements. A model of the geomagnetic field at geosynchronous altitude was derived including three basic field components - one generated within the

R. S. Harris

1978-01-01

116

The thermosphere, ionosphere, mesosphere energetics and dynamics (TIMED) spacecraft power system  

Microsoft Academic Search

The TIMED spacecraft is a three axis stabilized nadir pointing low Earth orbit scientific satellite with one side of the spacecraft always pointing away from the Sun. The instruments fields of view, pointing accuracy, jitter requirements, anti-sun pointing of one spacecraft side and sun angle variation during the year impose special demands on the power system design. The power subsystem

G. Dakermanji; M. Butler; P. U. Carlsson; D. Temkin

1997-01-01

117

Design of power electronics for TVC EMA systems  

Microsoft Academic Search

The Composite Development Division of the Propulsion Laboratory at Marshall Space Flight Center (MSFC) is currently developing a class of electromechanical actuators (EMA's) for use in space transportation applications such as thrust vector control (TVC) and propellant control valves (PCV). These high power servomechanisms will require rugged, reliable, and compact power electronic modules capable of modulating several hundred amperes of

R. Mark Nelms

1993-01-01

118

The control system for the X-33 linear aerospike engine  

Microsoft Academic Search

The linear aerospike engine is being developed for single-stage-to-orbit (SSTO) applications. The primary advantages of a linear aerospike engine over a conventional bell nozzle engine include altitude compensation, which provides enhanced performance, and lower vehicle weight resulting from the integration of the engine into the vehicle structure. A feature of this integration is the ability to provide thrust vector control

J. E. Jackson; E. Espenschied; J. Klop

1998-01-01

119

Computer-integrated micro-assembling with image-servo system for a microdroplet ejector  

Microsoft Academic Search

In this paper, the micro-assembling tasks of the positioning system are discussed; an automatic micro-assembling system with vision-servo system is proposed to replace manual operations for assembling a microdroplet ejector; it consists of three-axis micro-stepping positioning stage and the image recognition system, which is composed of two CCD cameras with lenses and a designed image recognition code in C++ builder.

C. J. Lin; G. Z. Chen; Y. X. Huang; J. K. Chang

2008-01-01

120

Design of power electronics for TVC and EMA systems  

NASA Astrophysics Data System (ADS)

The Component Development Division of the Propulsion Laboratory at Marshall Space Flight Center (MSFC) is currently developing a class of electromechanical actuators (EMA's) for use in space transportation applications such as thrust vector control (TVC) and propellant control valves (PCV). These high power servomechanisms will require rugged, reliable, and compact power electronic modules capable of modulating several hundred amperes of current at up to 270 volts. MSFC has selected the brushless dc motor for implementation in EMA's. A previous project performed by Auburn University examined the use of the resonant dc link (RDCL) inverter, pulse density modulation (PDM), and mos-controlled thyristors (MCT's) for speed control of a brushless dc motor. The speed of the brushless dc motor is proportional to the applied stator voltage. In a PDM system, the control system determines the number of resonant voltage pulses which must be applied to the stator to achieve a desired speed. The addition of a waveshaping circuit to the front end of a standard three-phase inverter yields a RDCL inverter; the resonant voltage pulses are produced through the action of this wave shaping circuit and the inverter. This project has focused on the implementation of a system which permits zero-voltage switching with the bus voltage clamped at the input voltage level. In the same manner as the RDCL inverter, the inverter selected for this implementation is a combination of waveshaping circuit and a standard three-phase inverter. In addition, this inverter allows a pulse-width modulated (PWM)-like control scheme instead of a PDM scheme. The operation of waveshaping circuit will be described through analysis and waveforms. Design relationships will also be presented.

Nelms, R. Mark; Bell, J. Brett; Shepherd, Michael T.

1994-11-01

121

Development of automatic polishing system and fuzzy-sliding mode control based on genetic algorithm  

Microsoft Academic Search

Polishing a die that has free-form surfaces is a time-consuming and tedious job, and requires a considerable amount of high-precision skill. We develop an automatic polishing system. The system has five degrees of freedom and is able to keep the polishing tool normal to the die surface during polishing process. The polishing system is composed of two subsystems, a three-axis

Seok Jo Go; Min Cheol Lee; Min Kyu Park

2001-01-01

122

Road condition monitoring using on-board Three-axis Accelerometer and GPS Sensor  

Microsoft Academic Search

A study by US Federal Highway Administration has shown that road condition is an essential factor of highway quality and smooth roads will lead to more comfortable driving experience and less municipal investment. International Roughness Index (IRI) has been widely used to measure pavement smoothness because it can provide a consistent rating for different measurement tools. However, existing measuring tools

Kongyang Chen; Mingming Lu; Xiaopeng Fan; Mingming Wei; Jinwu Wu

2011-01-01

123

Survey report for the biped locomotion robot compensating three-axis moment.  

National Technical Information Service (NTIS)

A dynamic walking simulation of biped locomotion robots based on the Zero Moment Point (ZMP) criterion is being conducted at JAERI. The ZMP criterion to obtain the stable walking patterns is that respective sums of moments around pitch-axis and roll-axis ...

I. Kato A. Takanishi E. Kume

1994-01-01

124

Three-Axis Time-Optimal Attitude Maneuvers of a Rigid-Body  

Microsoft Academic Search

With the development trends for modern satellites towards macro-scale and micro-scale, new demands are requested for its attitude adjustment. Precise pointing control and rapid maneuvering capabilities have long been part of many space missions. While the development of computer technology enables new optimal algorithms being used continuously, a powerful tool for solving problem is provided. Many papers about attitude adjustment

Xijing Wang; Jisheng Li

2002-01-01

125

Three-axis accelerometer package for slimhole and microhole seismic monitoring and surveys  

SciTech Connect

The development of microdrilling technology, nominally defined as drilling technology for 1-in.-diameter boreholes, shows potential for reducing the cost of drilling monitoring wells. A major question that arises in drilling microholes is if downhole logging and monitoring in general--and downhole seismic surveying in particular--can be conducted in such small holes since the inner working diameter of such a seismic tool could be as small as 0.31 in. A downhole three-component accelerometer package that fits within a 031-in. inner diameter tube has been designed, built, and tested. The package consists of three orthogonally mounted Entran EGA-125-5g piezoresistive silicon micromachined accelerometers with temperature compensation circuitry, downhole amplification, and line drivers mounted in a thin-walled aluminum tube. Accelerometers are commercially available in much smaller package sizes than conventional geophones, but the noise floor is significantly higher than that for the geophones. Cross-well tests using small explosives showed good signal-to-noise ratio in the recorded waveform at various receiver depths with a 1,50-ft source-receiver well separation. For some active downhole surveys, the accelerometer unit would clearly be adequate. It can be reasonably assumed, however, that for less energetic sources and for greater well separations, the high accelerometer noise floor is not acceptable. By expanding the inner working diameter of a microhole seismic tool to 0.5 in., other commercial accelerometers can be used with substantially lower noise floors.

Hunter, S.L.; Harben, P.E.

1997-01-07

126

Three-axis correction of distortion due to positional drift in scanning probe microscopy.  

PubMed

Two common sources of distortion in scanning probe microscopy are piezo creep and thermal drift, the latter caused by slow thermal expansions of materials in the sample and microscope due to small changes in temperature over the course of a scan. We present a technique for correcting distortion due to thermal drift along all three spatial axes, along with simultaneous correction of z-axis piezo creep. Our method works by comparing each scanned topographical image to a second, partial scan, taken immediately afterwards, on which the fast and slow scan axes have been reversed. We model the positional distortion as a low-order polynomial function in three dimensions, searching for the set of correctional coefficients that minimizes the root-mean-square difference between the two scans. We demonstrate in a variety of real-world and simulated tests that this technique can routinely reduce distortion from these effects by over 90%, often to a precision of better than a single pixel. PMID:22938307

Follin, Nathan D; Taylor, Keefer D; Musalo, Christopher J; Trawick, Matthew L

2012-08-01

127

Three-Axis Teslameter with Integrated Hall Probe Free from the Planar Hall Effect  

Microsoft Academic Search

The first commercially available teslameter with a fully integrated 3-axis Hall probe is described. The Hall probe chip contains horizontal and vertical Hall elements, analogue electronics, and a synchronisation circuit. A horizontal Hall element measures the perpendicular component, and two vertical Hall devices measure the two in-plane components of a magnetic field. Current spinning in the Hall devices cancels offset,

Dragana R. Popovic; Sasa Dimitrijevic; Marjan Blagojevic; Pavel Kejik; Enrico Schurig; Radivoje S. Popovic

2006-01-01

128

A real-time NURBS surface interpolator for precision three-axis CNC machining  

Microsoft Academic Search

Due to the fact that the cutting occurs around the cutter contact (CC) point, the efficiency and quality of CNC machining can be improved significantly if the CC velocity along the surface is kept costant. Conventional approaches to machining mainly maintain a constant cutter location (CL) velocity, so that the CC velocity along the surface is often not constant and

M.-C. Tsai; C.-W. Cheng; M.-Y. Cheng

2003-01-01

129

Articulated module flow guide system  

SciTech Connect

A system is disclosed for promoting selective shell-side flow distribution between and providing structural support for modular straight tube bundles in a heat exchanger or the like, wherein a plurality of flow guides, each of which includes three axi-symmetrically-located radial panels, are connected along their outer radial edges to form a polygonal array establishing mutually shared partitions between modular tube bundles. Various flow guide configurations permit gaps in the mutually shared partitions to promote uniform shell-side communication between the modules, and accommodate individual tube bundle support grids in assembled relation with the flow guides. 4 figs.

Van Hagan, T.H.; Tanner, D.E.

1980-07-15

130

TALON and CRADLE - Systems for the rescue of tumbling spacecraft and astronauts  

NASA Astrophysics Data System (ADS)

TALON (Tumble Arresting Large Oscillation Nullifier), a device capable of capturing a target in an uncontrolled three-axis tumble, and CRADLE (Concentric Rotating Astronaut Detumble Lifesaving Equipment), a device for rescuing a suited astronaut, are discussed. The physical nature of the tumbling problem is reviewed and the TALON/CRADLE system is described. A detailed examination of the way that TALON/CRADLE calculates the target motions and make appropriate adjustments is given.

Idle, Dunning, V.

1991-08-01

131

Development of a GPS-aided motion measurement, pointing, and stabilization system for a Synthetic Aperture Radar. [Global Positioning System (GPS)  

SciTech Connect

An advanced Synthetic Aperture Radar Motion Compensation System has been developed by Sandia National Laboratories (SNL). The system includes a miniaturized high accuracy ring laser gyro inertial measurement unit, a three axis gimbal pointing and stabilization assembly, a differential Global Positioning System (GPS) navigation aiding system, and a pilot guidance system. The system provides several improvements over previous SNL motion compensation systems and is capable of antenna stabilization to less than 0.01 degrees RMS and absolute position measurement to less than 5.0 meters RMS. These accuracies have been demonstrated in recent flight testing aboard a DHC-6-300 Twin Otter'' aircraft.

Fellerhoff, J.R.; Kohler, S.M.

1991-01-01

132

Autonomous wide-field-of-view star tracker system  

NASA Astrophysics Data System (ADS)

This paper describes the design of a low power, lightweight, three-axis, high accuracy, wide field of view (WFOV), CCD based Star Tracker System. The autonomous system will provide an inertial attitude reference for several lightweight, lowpower satellite programs underway at TRW. The paper includes the trades which led to the current design. Product performance, description, and verification are provided. The paper concludes with a development schedule, which includes a flight unit acceptance in January 1994, and closing comments regarding increased functionality and improved integration ease.

Schauwecker, Chris; Abreu, Rene; Plascyk, James A.

1993-11-01

133

Data-Driven Anomaly Detection Performance for the Ares I-X Ground Diagnostic Prototype.  

National Technical Information Service (NTIS)

In this paper, we will assess the performance of a data-driven anomaly detection algorithm, the Inductive Monitoring System (IMS), which can be used to detect simulated Thrust Vector Control (TVC) system failures. However, the ability of IMS to detect the...

B. L. Matthews M. A. Schwabacher R. A. Martin

2010-01-01

134

Parametric robustness analysis for Cassini spacecraft using the LMI approach without frequency sweep  

Microsoft Academic Search

A generalized Popov multiplier theory enables one to analyze system robustness with mixed real\\/complex parameters, repeated uncertainties, and multi-dimensional block uncertainties. Using the Cassini spacecraft thrust vector control (TVC) system as a design case study, modern robust control theory has been applied to the real flight project.

Richard Y. Chiang

1994-01-01

135

PROPULSION SIMULATIONS WITH THE UNSTRUCTURED-GRID CFD TOOL TetrUSS  

Microsoft Academic Search

A computational investigation has been completed to assess the capability of the NASA Tetrahedral Unstructured Software System (TetrUSS) for simulation of exhaust nozzle flows. Three configurations were chosen for this study: (1) a fluidic jet effects model, (2) an isolated nacelle with a supersonic cruise nozzle, and (3) a fluidic pitch- thrust-vectoring nozzle. These configurations were chosen because existing data

Karen A. Deere; Mohagna J. Pandya

136

Study of the optimization of satellite system design for transfer orbit  

NASA Astrophysics Data System (ADS)

Geostationary transfer orbit (GTO) characteristics of former geosynchronous satellites; satellite configurations as to GTO requirements; telemetry and telecommand, thermal, power, and attitude control subsystems as to stabilization modes and GTO constraints; and apogee injection strategies (single/multiple burn, steering law) were reviewed. The investigations were confined to 2 Ariane 4 payload classes (2500 kg in GTO, dual-launch and 4200 kg in GTO, single launch), three-axis or slow barbecue stabilization during transfer orbit, and use of a liquid apogee injection system with low thrust level (400 N). A recommendation for an overall system optimization is presented.

Baetz; Fetzer, K.; Fink, W.; Hufnagel, H.; Kellermeier, H.; Kleinau; Mueller, W.; Chalmers, H.

1983-04-01

137

Testing the three axis magnetometer and gradiometer MOURA and data comparison on San Pablo de los Montes Observatory.  

NASA Astrophysics Data System (ADS)

A magnetometer and gradiometer named MOURA has been developed with the objective to measure the magnetic field on Mars in the frame of Mars MetNet Precursor Mission (MMPM) [1]. MOURA is a compact, miniaturized, intelligent and low cost instrument, based on two sets of triaxial magnetometers separated one centimeter from each other to do gradiometry studies. It has a resolution of 2.2 nT, and a field range of + 65?T, which can be extended to +130 ?T when sensors are saturated. [2] These sensor heads are Anisotropic MagnetoResistances (AMR) Commercial-Off-The-Shelf (COTS) by Honeywell, specifically HMC1043, which has been selected due to their relative low consumption, weight and size, factors very important for the mission with very limited mass and power budget (shared 150 g for three full payloads). Also, this technology has been previously successfully employed on board Unmanned Aerial Vehicles (UAV) to perform geomagnetic surveys in extreme conditions areas [3], and in several space missions for different applications. [4] After the development of the MOURA Engineering Qualification Model (EQM) in November 2011, an exhaustive set of tests have been performed to validate and fully characterize the instrument. Compensation equations have been derived for the temperature corrections in the operation range (between -135 °C and 30 °C) in controlled environments. These compensation equations have been applied to field data, which have shown to follow the daily Earth's magnetic field variations as registered by San Pablo Geomagnetic Observatory (IAGA code: SPT) (available at www.ign.es and www.intermagnet.org) with deviations lower than 40 nT. These deviations were attributed to several error factors as the different locations between MOURA and SPT and other possible different geomagnetic conditions. Due to the above, a measurement campaign on SPT installations are been done. The main objective is to compare MOURA measurements on a relevant environment, with data obtained by SPT magnetometers. This is considered the last step prior to Mars in situ measurements. SPT employs for geomagnetic observations a fluxgate magnetometer FGE-Danish Meteorological Institute and a fluxgate vector magnetometer Geomag M390, both equipped with Overhauser effect magnetometers GSM90. The conditions into the rooms that contain these instruments are controlled. The equipments are situated on several pillars fixed strategically at Earth surface avoiding vibrations and other Earth movement that could affect measurement due to changes on the sensor position, the region is magnetically clean and the temperature variation is very low. Magnetic measurements are performed by MOURA for several days located on one of these pillars. These measurements are compared with SPT reference instrumentation with the aim to obtain a direct and very accurate evaluation of MOURA facing reference instrumentation. http://metnet.fmi.fi/index.php Development of miniaturized instrumentation for Planetary Exploration and its application to the Mars MetNet Precursor Mission. H. Guerrero et al. EGU General Assembly 2010, held 2-7 May, 2010 in Vienna, Austria, p.13330 Funaki, M.; Hirasawa, N.; and the Ant-Plane Group. Outline of a small unmanned aerial vehicle (Ant-Plane) designed for Antartic research. Polar Science 2008, 2, 129-142. M. Diaz-Michelena Sensors 2009, 9(4), 2271-2288

Belen Fernandez, Ana; Sanz, Ruy; Covisa, Pablo; Tordesillas, Jose Manuel; Diaz-Michelena, Marina

2013-04-01

138

Eclipse II: a new parallel mechanism enabling continuous 360-degree spinning plus three-axis translational motions  

Microsoft Academic Search

This paper presents the Eclipse II, a new six-degrees-of-freedom parallel mechanism, which can be used as a basis for general motion simulators. The Eclipse II is capable of x, y, and z axes translations, and a, b, and c axes rotations. In particular, it has the advantage of enabling continuous 360° spinning of the platform. We first describe the computational

Jongwon Kim; Jae-Chul Hwang; Jin-Sung Kim; Cornel C. Iurascu; Frank Chongwoo Park; Young Man Cho

2002-01-01

139

A novel portable seizure detection alarm system: preliminary results.  

PubMed

The unpredictable and random occurrence of seizures is of the most distressful issue affecting patients and their families. Unattended seizures can have serious consequences including injury or death. The objective of this study is to develop a small, portable, wearable device capable of detecting seizures and alerting patients and families on recognition of specific seizures' motor activity. Ictal data were prospectively obtained in consecutive patients admitted to two video-EEG units. This study included patients with a history of motor seizures, clonic or tonic, or tonic-clonic seizures or patients with complex partial seizures with frequent secondary generalization. A "Motion Sensor" unit mounted on a bracelet was attached to one wrist. The "Sensor" contains a three-axis accelerometer and a transmitter. The three-axis movements' data were transmitted to a portable computer. Algorithm specially developed for this purpose analyzed the recorded data. Seizures' alerts were compared with the video-EEG data. Ictal data were acquired in 15 of the 31 recruited patients. The algorithm correctly identified 20 of 22 (91%) captured seizures and generated an alarm within a median period of 17 seconds. All events lasting >30 seconds (i.e., 19 events) were identified. The system failed to identify 2 of 22 seizures (9%). There were eight false alarms during 1,692 hours of monitoring. Preliminary data suggest that this motion detection device/alarm system can identify most motor seizures with high sensitivity and with a low false alarm rate. PMID:21221012

Kramer, Uri; Kipervasser, Svetlana; Shlitner, Arie; Kuzniecky, Ruben

2011-02-01

140

A study of variable thrust, variable specific impulse trajectories for solar system exploration  

NASA Astrophysics Data System (ADS)

A study has been performed to determine the advantages and disadvantages of variable thrust and variable Isp (specific impulse) trajectories for solar system exploration. There have been several numerical research efforts for variable thrust, variable Isp, power-limited trajectory optimization problems. All of these results conclude that variable thrust, variable Isp (variable specific impulse, or VSI) engines are superior to constant thrust, constant Isp (constant specific impulse; or CSI) engines. However, most of these research efforts assume a mission from Earth to Mars, and some of them further assume that these planets are circular and coplanar. Hence they still lack the generality. This research has been conducted to answer the following questions: (1) Is a VSI engine always better than a CSI engine or a high thrust engine for any mission to any planet with any time of flight considering lower propellant mass as the sole criterion? (2) If a planetary swing-by is used for a VSI trajectory, is the fuel savings of a VSI swing-by trajectory better than that of a CSI swing-by or high thrust swing-by trajectory? To support this research, an unique, new computer-based interplanetary trajectory calculation program has been created. This program utilizes a calculus of variations algorithm to perform overall optimization of thrust, Isp, and thrust vector direction along a trajectory that minimizes fuel consumption for interplanetary travel. It is assumed that the propulsion system is power-limited, and thus the compromise between thrust and Isp is a variable to be optimized along the flight path. This program is capable of optimizing not only variable thrust trajectories but also constant thrust trajectories in 3-D space using a planetary ephemeris database. It is also capable of conducting planetary swing-bys. Using this program, various Earth-originating trajectories have been investigated and the optimized results have been compared to traditional CSI and high thrust trajectory solutions. Results show that VSI rocket engines reduce fuel requirements for any mission compared to CSI rocket engines. Fuel can be saved by applying swing-by maneuvers for VSI engines; but the effects of swing-bys due to VSI engines are smaller than that of CSI or high thrust engines.

Sakai, Tadashi

141

Solar Pointing Attitude Rocket Control System /SPARCS/  

NASA Astrophysics Data System (ADS)

The SPARCS system is described and its use since Dec. 1967 is reviewed. SPARCS was developed to fulfill a requirement for a lightweight, precision, three-axis pointing control system for solar-sounding rockets. The use of sounding rockets to calibrate satellite instruments before flight for subsequent recovery and orbital flight is noted, along with the calibration of Skylab instruments with sounding rocket payloads. The gyroless SPARCS weights under 36 lb, is 6 in. in diam, and is self-contained regarding electronics, pneumatics, gas supply, electrical power, and coarse solar sensors. A two-axis sensor measures pitch and yaw error relative to the solar vector, and functions by pointing the longitudinal axis toward the radiometric center of the sun. Pointing errors cause voltages which activate pneumatic valves, allowing miniature gas jets to zero the pointing error. SPARCS has been used successfully on 100 missions.

Shigemoto, J. M.

1982-05-01

142

Head-aimed vision system improves tele-operated mobility  

NASA Astrophysics Data System (ADS)

A head-aimed vision system greatly improves the situational awareness and decision speed for tele-operations of mobile robots. With head-aimed vision, the tele-operator wears a head-mounted display and a small three axis head-position measuring device. Wherever the operator looks, the remote sensing system "looks". When the system is properly designed, the operator's occipital lobes are "fooled" into believing that the operator is actually on the remote robot. The result is at least a doubling of: situational awareness, threat identification speed, and target tracking ability. Proper system design must take into account: precisely matching fields of view; optical gain; and latency below 100 milliseconds. When properly designed, a head-aimed system does not cause nausea, even with prolonged use.

Massey, Kent

2004-12-01

143

Vector magnetometry and lightwave defect imaging sensor technologies for internal pipe inspection systems: Phase 1 and 2 feasibility study, conceptual design, and prototype development  

NASA Astrophysics Data System (ADS)

The Gas Research Institute (GRI) has been sponsoring the development of a vehicle and sensors for an integrated nondestructive internal inspection system for natural gas distribution pipes. Arthur D. Little has developed two sensor technologies; Vector Magnetometry (VM) and Lightwave Defect Imaging (LDI) for the system.The Vector Magnetometry sensor utilizes multiple arrays of miniature detection coils (fluxgate magnetometer elements): a three-axis array measures both the amplitude and phase of the magnetic leakage field that occurs in the vicinity of pipe wall defects. This technology is applicable to both cast iron and steel pipe.

Carroll, Steven; Fowler, Thomas; Peters, Edward; Power, Wendy; Reed, Michael

1994-01-01

144

Tactile Sensing-based Control System for Dexterous Robot Manipulation  

NASA Astrophysics Data System (ADS)

Object manipulation is one crucial task in robotics. This chapter presents a precision control scheme of a multi-fingered humanoid robot arm based on tactile sensing information to perform object manipulation tasks. We developed a novel optical three-axis tactile sensor system mounted on the fingertips of a humanoid robot to enhance its ability to recognize and manipulate objects. This tactile sensor can acquire normal and shearing forces. Trajectory generation based on kinematical solutions at the arm and fingers, combined with control system structure and a sensing principle of a tactile sensor system, is presented. Object manipulation experiments are conducted using hard and soft objects. Experimental results revealed that the proposed control scheme enables the finger system to recognize low force interactions based on tactile sensing information to grasp the object surface and manipulate it without damaging the object or the sensor elements.

Yussof, Hanafiah; Ohka, Masahiro; Suzuki, Hirofumi; Morisawa, Nobuyuki

145

A Novel Sensor-Assisted RFID-Based Indoor Tracking System for the Elderly Living Alone  

PubMed Central

The population of elderly people is increasing rapidly in many developed nations. Providing safe and comfortable care to aging people is an important social goal. Moreover, obtaining correct activity and location information for an elderly person is an important research goal. This work proposes a novel intelligent RFID-based indoor tracking system for elderly people living alone. The proposed system uses environment information for inhabitants and received signal strength of an RFID reader to estimate the probable location of an inhabitant. The proposed system then coordinates with the wireless sensor node of a three-axis accelerometer and uses a genetic algorithm to compute the location of the inhabitant. The proposed system also uses context and gait information to improve inhabitant-tracking accuracy. Experiment results show that the accuracy of the proposed system is better than that of existing RFID-based systems.

Hsu, Chien-Chang; Chen, Jun-Hao

2011-01-01

146

Wellborne inertial navigation system  

SciTech Connect

A phototype wireline tool which includes a downhole inertial platform and a surface computer to spatially map a well is described. The hardware consists of a single-gimbaled inertial platform with accelerometers and gyros to obtain three-axis motion information. The gyroscope and accelerometer outputs are transmitted to a computer at the surface which calculates probe attitude relative to north, east, and vertical. Double integration of the accelerometer data provides the position information. A conventional 7-conductor wireline is used for the system data transmission. System accuracy is enhanced by advances made in the computer software which processes the data received from the tool. The software uses statistical sampling estimation to obtain optimal estimates of the system errors. Measurement errors are determined by periodically stopping the tool during the logging procedure and observing the indicated velocity measurements. This procedure, known as Kalman filtering, results in increased accuracy of the data. Present mapping systems have an X-Y-Z location accuracy of +- 100 to +- 200 feet for a typical well depth of 10,000 feet. Test results show that the new system is accurate to about +- 1 foot per 1000 feet of well depth. Unlike conventional systems, the inertial navigator does not require any sort of projection of the cable length (which may not be accurately known). Also this system provides continuous data throughout the wellbore and logging speeds on the order of 10 ft/sec appear possible. The hardware and software associated with this mapping system are described and the recent field test results are reported.

Kelsey, J.R.

1983-01-01

147

Towards UAV Nap-of-the-Earth Flight Using Optical Flow  

Microsoft Academic Search

Nap-of-the-Earth (NOE) flight and the development of advanced Unmanned Air Vehicles (UAV) require further integration of sensors\\u000a and onboard processing. Flying insects feature a panoramic eye which relies on Optical Flow (OF) for guidance and obstacle\\u000a avoidance. We describe the development of a miniature thrust-vectoring UAV featuring an analog electronic eye based on biological\\u000a motion detection. The system is tested

Thomas Netter; Nicolas H. Franceschini

1999-01-01

148

High fidelity ground effect model based on DGPS data  

Microsoft Academic Search

A global model approach developed on the X-31 EFM data was recently improved during the experimental aircraft program X-31 VECTOR. The VECTOR program is briefly presented, focusing on extremely precise ESTOL (Extremely Short Take-Off and Landing) manoeuvre following a slow, thrust-vectored approach at high angle of attack. High accuracy navigation and inertial sensor systems enable onboard calculation of the height

Detlef Rohlf; Holger Friehmelt

2005-01-01

149

Sonda IV Brazilian rocket - The major step for the future national satellite launcher  

NASA Astrophysics Data System (ADS)

A development status account is given of Brazil's current sounding rocket development program. The two-stage Sonda IV sounding rocket is in effect a solid fuel rocket motor launch vehicle testbed for a planned 'VLS' four-stage satellite launch vehicle. VLS payload capability is nominally given as 120 kg to 1000-km (25-deg) circular orbit. A fluid-injection thrust vector control system under development in the Sonda program will also be employed in the VLS first stage.

Boscov, J.; Bernardes, J. A.; Yoshino, T.; Furlan, B. M.

1986-10-01

150

A wellbore inertial navigation system  

SciTech Connect

A prototype wireline tool which includes a downhole inertial platform and a surface computer to spatially map a well is described. The hardware consists of a single-gimballed inertial platform with accelerometers and gyros to obtain three-axis motion information. The gyroscope and accelerometer outputs are transmitted to a computer at the surface which calculates probe attitude relative to north, east, and vertical. Double integration of the accelerometer data provides the position information. A conventional 7-conductor wireline is used for the system data transmission. System accuracy is enhanced by advances made in the computer software which processes the data received from the tool. The software uses statistical sampling estimation to obtain optimal estimates of the system errors. Measurement errors are determined by periodically stopping the tool during the logging procedure and observing the indicated velocity measurements. This procedure, known as Kalman filtering, results in increased accuracy of the data. Present mapping systems have an X-Y-Z location accuracy of 100 to 200 feet for a typical well depth of 10,000 feet. Test results show that the new system is accurate to about 1 foot per 1000 feet of well depth. Unlike conventional systems, the inertial navigator does not require any sort of projection of the cable length (which may not be accurately known). Also, this system provides continuous data throughout the wellbore and logging speeds on the order of 10 ft/sec appear possible. The hardware and software associated with this mapping system are described and the recent field test results are reported.

Kelsey, J.R.

1983-02-01

151

The control of satellites with microgravity constraints: The COMET Control System  

NASA Astrophysics Data System (ADS)

The COMET attitude determination and control system, using inverse dynamics and a novel torque distribution/momentum management technique, has shown great flexibility, performance, and robustness. Three-axis control with two wheels is an inherent consequence of inverse dynamics control which allows for reduction in spacecraft weight and cost, or alternatively, provides a simple means of failure-redundancy for three-wheel spacecraft. The control system, without modification, has continued to perform well in spite of large changes in spacecraft mass properties and mission orbit altitude that have occurred during development. This flexibility has obviated imposition of early stringent ADACS design constraints and has greatly reduced commonly incurred ADACS modification costs and delay associated with program maturation.

Grossman, Walter; Freesland, Douglas

1994-05-01

152

Three-axis measurement and cancellation of background magnetic fields to less than 50 µG in a cold atom experiment  

NASA Astrophysics Data System (ADS)

Many experiments involving cold and ultracold atomic gases require very precise control of magnetic fields that couple to and drive the atomic spins. Examples include quantum control of atomic spins, quantum control and quantum simulation in optical lattices, and studies of spinor Bose condensates. This makes accurate cancellation of the (generally time dependent) background magnetic field a critical factor in such experiments. We describe a technique that uses the atomic spins themselves to measure dc and ac components of the background field independently along three orthogonal axes, with a resolution of a few tens of µG in a bandwidth of ~1 kHz. Once measured, the background field can be cancelled with three pairs of compensating coils driven by arbitrary waveform generators. In our laboratory, the magnetic field environment is sufficiently stable for the procedure to reduce the field along each axis to less than ~50 µG rms, corresponding to a suppression of the ac part by about one order of magnitude. This suggests that our approach can provide access to a new low-field regime in cold atom experiments.

Smith, A.; Anderson, B. E.; Chaudhury, S.; Jessen, P. S.

2011-10-01

153

Structure health assessment and warning system (SHAWS)  

NASA Astrophysics Data System (ADS)

We are developing a Structure Health Assessment and Warning System (SHAWS) based on building displacement measurements and wireless communication. SHAWS will measure and predict the stability/instability of a building, determine whether it is safe for emergency responders to enter during an emergency, and provide individual warnings on the condition of the structure. SHAWS incorporates remote sensing nodes (RSNs) installed on the exterior frame of a building. Each RSN includes a temperature sensor, a three-axis accelerometer making static-acceleration measurements, and a ZigBee wireless system (IEEE 802.15.4). The RSNs will be deployed remotely using an air cannon delivery system, with each RSN having an innovative adhesive structure for fast (<10 min) and strong installation under emergency conditions. Once the building has moved past a threshold (~0.25 in./building story), a warning will be issued to emergency responders. In addition to the RSNs, SHAWS will include a base station located on an emergency responder's primary vehicle, a PDA for mobile data display to guide responders, and individual warning modules that can be worn by each responder. The individual warning modules will include visual and audio indicators with a ZigBee receiver to provide the proper degree of warning to each responder.

Bock, Daniel M.; Kim, Keehoon; Mapar, Jalal

2008-04-01

154

Beam Position and Phase Monitor - Wire Mapping System  

SciTech Connect

The Los Alamos Neutron Science Center (LANSCE) deploys many cylindrical beam position and phase monitors (BPPM) throughout the linac to measure the beam central position, phase and bunched-beam current. Each monitor is calibrated and qualified prior to installation to insure it meets LANSCE requirements. The BPPM wire mapping system is used to map the BPPM electrode offset, sensitivity and higher order coefficients. This system uses a three-axis motion table to position the wire antenna structure within the cavity, simulating the beam excitation of a BPPM at a fundamental frequency of 201.25 MHz. RF signal strength is measured and recorded for the four electrodes as the antenna position is updated. An effort is underway to extend the systems service to the LANSCE facility by replacing obsolete electronic hardware and taking advantage of software enhancements. This paper describes the upgraded wire positioning system's new hardware and software capabilities including its revised antenna structure, motion control interface, RF measurement equipment and Labview software upgrades. The main purpose of the wire mapping system at LANSCE is to characterize the amplitude response versus beam central position of BPPMs before they are installed in the beam line. The wire mapping system is able to simulate a beam using a thin wire and measure the signal response as the wire position is varied within the BPPM aperture.

Watkins, Heath A [Los Alamos National Laboratory; Shurter, Robert B. [Los Alamos National Laboratory; Gilpatrick, John D. [Los Alamos National Laboratory; Kutac, Vincent G. [Los Alamos National Laboratory; Martinez, Derwin [Los Alamos National Laboratory

2012-04-10

155

Portable activity monitoring system for temporal parameters of gait cycles.  

PubMed

A portable and wireless activity monitoring system was developed for the estimation of temporal gait parameters. The new system was built using three-axis accelerometers to automatically detect walking steps with various walking speeds. The accuracy of walking step-peak detection algorithm was assessed by using a running machine with variable speeds. To assess the consistency of gait parameter analysis system, estimated parameters, such as heel-contact and toe-off time based on accelerometers and footswitches were compared for consecutive 20 steps from 19 individual healthy subjects. Accelerometers and footswitches had high consistency in the temporal gait parameters. The stance, swing, single-limb support, and double-limb support time of gait cycle revealed ICCs values of 0.95, 0.93, 0.86, and 0.75 on the right and 0.96, 0.86, 0.93, 0.84 on the left, respectively. And the walking step-peak detection accuracy was 99.15% (±0.007) for the proposed method compared to 87.48% (±0.033) for a pedometer. Therefore, the proposed activity monitoring system proved to be a reliable and useful tool for identification of temporal gait parameters and walking pattern classification. PMID:20703612

Lee, Jung-Ah; Cho, Sang-Hyun; Lee, Young-Jae; Yang, Heui-Kyung; Lee, Jeong-Whan

2009-06-16

156

Magnetic Position and Orientation Tracking System  

Microsoft Academic Search

Three-axis generation and sensing of quasi-static magneticdipole fields provide information sufficient to determine both the position and orientation of the sensor relative to the source. Linear rotation transformations based upon the previous measurements are applied to both the source excitation and sensor output vectors, yielding quantities that are linearly propotional to small changes in the position and orientation. Changes are

Frederick Raab; Ernest Blood; Terry Steiner; Herbert Jones

1979-01-01

157

A vector fetal magnetocardiogram system with high sensitivity  

NASA Astrophysics Data System (ADS)

The vector fetal magnetocardiogram (V-FMCG) system that measures the three orthogonal components of the magnetic field from a fetal heart has been developed to clearly observe fetal cardiac activity during pregnancy by using the superconducting quantum interference device. To detect a clear V-FMCG signal, the bottom of the cryostat was made of thin glass-fiber-reinforced plastic and the total length between the pickup coil to the outer surface is 12 mm. Because the cryostat bottom was made thinner, the area of the cryostat's top and bottom could be made smaller, thus a low evaporation loss (<1.2 l per day) and a long refilling interval (>10 days) were obtained. The gantry was able to tilt the cryostat and the bed could move in three axis directions, which made it possible to easily locate the vector pickup coil at an optimum position to obtain the maximum magnetic field from a fetal heart. We obtained V-FMCGs from 21 normal fetuses with gestation periods of 27-38 weeks. Using these vector signals, the dipoles were estimated and the relationship between the strength of the dipole moments and the number of gestation weeks could be obtained. Thus, V-FMCG seems to represent a new noninvasive tool for clearly detecting the electrophysiological activity of a fetal heart.

Kandori, Akihiko; Miyashita, Tsuyoshi; Tsukada, Keiji; Horigome, Hitoshi; Asaka, Mitsuhiro; Shigemitsu, Sadahiko; Takahashi, Miho; Terada, Yasushi; Mitsui, Toshio; Chiba, Yoshihide

1999-12-01

158

Numerical investigation of the thrust efficiency of a laser-propelled vehicle  

NASA Astrophysics Data System (ADS)

The flow situation for a thruster propelled by ablated gas which is energized by a laser pulse is numerically simulated. The flow is axisymmetric and nonsteady, and is assumed to be inviscid due to its high Reynolds number. The high pressure expansion of the laser heated gas generated thrust as it pushes against the vehicle. Gas expansion lateral to the thrust vector causes performance to decrease. The vehicle geometry and the laser pulse characteristics determine the degree to which the flow is one dimensional. As the thruster's parameters are varied, its impulse is calculated and compared to the limiting impulse of a one-dimensional system, and thus the thrust efficiency is computed.

Mulroy, James Randolph

1991-05-01

159

Application of finite element method to hypersonic nozzle flow computations  

NASA Astrophysics Data System (ADS)

An explicit Taylor-Galerkin Finite Element Method (FEM) algorithm, used for the solution of Euler/Navier-Stokes equations, is applied for the computation of steady-state frozen equilibrium flow in single expansion ramp nozzles (SERN) and in plug nozzles for hypersonic propulsion systems. External flow conditions are taken into account. For the determination of nozzle performance a detailed 2D/3D-flow analysis in regions with complex geometries was performed using unstructured computational grids with adaptive mesh refinement. Some results for the investigated nozzle configurations at different flight conditions are presented and discussed. Additionally, thrust vectoring by modification of the lower nozzle flap shape was studied.

Koschel, W.; Rick, W.; Bikker, S.

1992-02-01

160

Micro-electro-mechanical system (MEMS) component research and development for army missile applications  

NASA Astrophysics Data System (ADS)

The US Army Aviation and Missile Command Missile Research, Development and Engineering Center has identified MEMS as an emerging technology with high potential for fulfilling the mission of future missiles. The technology holds the promise of reducing the size, weight, cost, and power requirements for performing existing functions in Army missile systems, as well las providing opportunities for new computing, sensing, and actuation functions that cannot be achieved with conventional electromechanical technology. MEMS will enable the Army's next generation of smaller and lighter missiles. The military market drives the thrust for development of miniature sensor with applications such as: competent and smart munitions, aircraft and missile autopilots, tactical missile guidance, fire control system, platform stabilization, smart structures with embedded inertial sensors, missile system health monitoring, missile and ground-based radar, radio frequency seekers, aerodynamic flow control, IR imagers, and multiple intelligent small projectiles. Current efforts at AMCOM include the development of MEMS-based inertial components to include accelerometers with wide dynamic range, tactical grade gyros with high rate range, and miniature three-axis inertial measurement unit with common interface electronics. Performance requirements of such components will be presented in terms of current and future Army missile systems. Additional MEMS based efforts under investigation at AMCOM include missile storage health monitoring, RF MEMS components, encoders for actuators, and aerodynamic flow control will also be discussed.

Hudson, Tracy D.; McMillen, Deanna K.; Ashley, Paul R.; Ruffin, Paul B.; Baeder, Janet

1999-07-01

161

IRECIN Nano-satellite communication system and ground segment  

NASA Astrophysics Data System (ADS)

On board resources necessary to perform the mission tasks are very limited in nano-satellites. This paper proposes a real-time multi-processing system for the communication system between ground segment and IRECIN nano-satellite. The first microprocessor is devoted to interface to the rice-transceiver subsystem decoding packet information and the second one is in charge to communicate with the other subsystems through I2C bus. It uses UHF band and less than 1 W in RF. All electronic components are SMD technology in order to reduce weight and size. The realized electronic boards are completely developed, realized and tested at the Vitrociset S.P.A. under control of Research and Develop Group. This multi-processor system even allows managing the tasks of the microprocessor eventually damaged, the microprocessor still working takes the functionalities of the first one using simpler algorithms. This choice assures an increasing nano-satellite life time. Moreover, the depicted method allows to free the on-board main microprocessor from the control functions of the communication data, increasing its communication capabilities with the other subsystems. The proposed system is implemented on the IRECIN, a modular nano-satellite weighing less than 1.5 kg, constituted by 16 external sides with surface-mounted solar cells and three internal Al plates, kept together by four steel bars. Lithium-ion batteries are added for eclipse operations. Attitude is determined by two three-axis magnetometers and the solar panel data. Control is provided by an active magnetic control system. The spacecraft will be spin-stabilized with the spin-axis normal to the orbit.

Ferrante, M.; Povia, M.; di Ciolo, L.; Ortenzi, A.; Petrozzi, M.

2005-01-01

162

Development of a compact micro-stereolithography (MSTL) system using a Blu-ray optical pickup unit  

NASA Astrophysics Data System (ADS)

In this paper, a compact micro-stereolithography (MSTL) apparatus of tabletop size was designed and constructed using a Blu-ray optical pickup unit (OPU), which came from a commercial Blu-ray optical disk driver. This is the very first application of a Blu-ray OPU to a light source of a MSTL system. A three-axis stage was adopted to obtain 3D motions, and a simple optic system was added to extend the focal length of a Blu-ray OPU for avoiding the physical interference. A liquid photo-curable resin suitable for the system was recomposed by modifying previously reported one. Then, the fabrication characteristics were investigated by constructing single-line structures at varying parameters such as laser power, scan speed and aperture diameter. The cured depth and width of the single-line structures decreased as the irradiated energy, which is determined by laser power and scan speed, decreased. Interestingly, the result also showed that the aperture diameter can effectively control the aspect ratio of cured depth and width. The increase of aperture diameter brings about the decrease of cured depth and increase of cured width. Based on the results of single-line exposure experiment, various 3D micro-structures were successfully fabricated. From this study, it can be shown that the Blu-ray-based MSTL system and the resin are suitable for fabricating complicated 3D micro-structures with reproducibility.

Kang, Hyun-Wook; Jeong, Young-Seok; Lee, Seung-Jae; Kim, Kyung-Soo; Yun, Won-Soo

2012-11-01

163

Design of the infrared fast steering mirror chopping control system for the Keck II Telescope  

NASA Astrophysics Data System (ADS)

The Keck 2 ten meter telescope will utilize an advanced chopping secondary mirror in order to enhance observations in the infrared. The Infrared Fast Steering Mirror (IFSM) can execute a square-wave chop at frequencies as high as 25 Hz with an accuracy of +/- 0.1 arcsec. Chopping can be synchronized by focal plane instruments, and the system can simultaneously perform high-performance chopping as well as beam-steering (for atmospheric correction), providing the Keck telescope with greatly enhanced capability. Details of design, testing, and performance of the Keck 2 IFSM are presented in this paper. The mirror is controlled by three voice coil actuators. Reaction forces generated by the actuators are absorbed by a reaction mass suspended from the main IFSM structure. Motor driven springs are used to minimize power dissipation in the actuators. The IFSM all- digital control system uses a unique adaptive algorithm that forces the mirror to precisely follow the commanded chop waveform. Tests use various computerized instruments: a three-axis laser interferometer for calibration and stability, a 6-axis dynamometer to evaluate reaction forces transmitted to the telescope. In addition to specifics of the design, performance, and testing, a video illustrating details of the IFSM hardware and showing it in operation will be presented.

Aubrun, Jean-Noel; Lorell, Kenneth R.; Feher, Gregory J.; Perez, Ernesto O.; Reshatoff, Paul J.; Zacharie, Donald F.

1998-08-01

164

Structure and properties of nano-hydroxypatite scaffolds for bone tissue engineering with a selective laser sintering system  

NASA Astrophysics Data System (ADS)

In this study, nano-hydroxypatite (n-HAP) bone scaffolds are prepared by a homemade selective laser sintering (SLS) system based on rapid prototyping (RP) technology. The SLS system consists of a precise three-axis motion platform and a laser with its optical focusing device. The implementation of arbitrary complex movements based on the non-uniform rational B-Spline (NURBS) theory is realized in this system. The effects of the sintering processing parameters on the microstructure of n-HAP are tested with x-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy and scanning electron microscopy (SEM). The particles of n-HAP grow gradually and tend to become spherical-like from the initial needle-like shape, but still maintain a nanoscale structure at scanning speeds between 200 and 300 mm min - 1 when the laser power is 50 W, the light spot diameter 4 mm, and the layer thickness 0.3 mm. In addition, these changes do not result in decomposition of the n-HAP during the sintering process. The results suggest that the newly developed n-HAP scaffolds have the potential to serve as an excellent substrate in bone tissue engineering.

Shuai, Cijun; Gao, Chengde; Nie, Yi; Hu, Huanlong; Zhou, Ying; Peng, Shuping

2011-07-01

165

Structure and properties of nano-hydroxypatite scaffolds for bone tissue engineering with a selective laser sintering system.  

PubMed

In this study, nano-hydroxypatite (n-HAP) bone scaffolds are prepared by a homemade selective laser sintering (SLS) system based on rapid prototyping (RP) technology. The SLS system consists of a precise three-axis motion platform and a laser with its optical focusing device. The implementation of arbitrary complex movements based on the non-uniform rational B-Spline (NURBS) theory is realized in this system. The effects of the sintering processing parameters on the microstructure of n-HAP are tested with x-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy and scanning electron microscopy (SEM). The particles of n-HAP grow gradually and tend to become spherical-like from the initial needle-like shape, but still maintain a nanoscale structure at scanning speeds between 200 and 300 mm min(-1) when the laser power is 50 W, the light spot diameter 4 mm, and the layer thickness 0.3 mm. In addition, these changes do not result in decomposition of the n-HAP during the sintering process. The results suggest that the newly developed n-HAP scaffolds have the potential to serve as an excellent substrate in bone tissue engineering. PMID:21642759

Shuai, Cijun; Gao, Chengde; Nie, Yi; Hu, Huanlong; Zhou, Ying; Peng, Shuping

2011-06-06

166

Finding an environmentally acceptable replacement for Halon 2402 that meets Minuteman LITVC performance criteria  

NASA Astrophysics Data System (ADS)

Halon 2402 (Freon 114B2) is injected into the hot gas exhaust stream of the Minuteman second-stage solid propellant rocket motor nozzle to provide thrust vector control. In response to environmental concerns, specifically ozone depletion, the U.S. Air Force has established a program to find and qualify a replacement for Halon 2402. Because of anticipated schedule constraints, two parallel paths consisting of a 'drop-in' replacement, and a complete thrust vector control system redesign will be pursued during the first phase of the program. Tasks within the first phase support a series of candidate down selections. These tasks include review of various data bases for possible candidates and then evaluating the candidates in terms of environmental effects, cost, storability, compatibility, packaging, and performance. The culmination of the first phase will be two static motor firings in which two drop-in injectant candidates and two redesign system candidates will be tested to determine actual performance. The results of the firings will dictate which path (drop-in or redesign) and which injectant to pursue for formal qualification. Presently, Phase I is approximately 50 percent complete with the many candidates being reduced to three for each path.

Shell, Vaughn; Marlow, Mike; Nimitz, Jon

1992-07-01

167

Development of a two-dimensional dual pendulum thrust stand for Hall thrusters  

SciTech Connect

A two-dimensional dual pendulum thrust stand was developed to measure thrust vectors (axial and horizontal (transverse) direction thrusts) of a Hall thruster. A thruster with a steering mechanism is mounted on the inner pendulum, and thrust is measured from the displacement between inner and outer pendulums, by which a thermal drift effect is canceled out. Two crossover knife-edges support each pendulum arm: one is set on the other at a right angle. They enable the pendulums to swing in two directions. Thrust calibration using a pulley and weight system showed that the measurement errors were less than 0.25 mN (1.4%) in the main thrust direction and 0.09 mN (1.4%) in its transverse direction. The thrust angle of the thrust vector was measured with the stand using the thruster. Consequently, a vector deviation from the main thrust direction of {+-}2.3 deg. was measured with the error of {+-}0.2 deg. under the typical operating conditions for the thruster.

Nagao, N.; Yokota, S.; Komurasaki, K.; Arakawa, Y. [Department of Aeronautics and Astronautics, University of Tokyo, 7-3-1, Hongo, Bunkyo-ku, Tokyo 113-8656 (Japan); Department of Advanced Energy, University of Tokyo, 7-3-1, Hongo, Bunkyo-ku, Tokyo 113-8656 (Japan); Department of Aeronautics and Astronautics, University of Tokyo, 7-3-1, Hongo, Bunkyo-ku, Tokyo 113-8656 (Japan)

2007-11-15

168

Terrestrial Attitude Estimation for the Formation Control Testbed (FCT)  

Microsoft Academic Search

In this paper we look at the problem of terrestrial (earth based) attitude estimation of a unique robotic vehicle using full three axis attitude measurements and three axis inertial rate sensors (gyros). The vehicle is completely autonomous and uses air bearings to simulate the drag free dynamic environment of space. An onboard infrared camera system is used to provide quaternion

J. Shields; H. Goldberg; J. Kiem; M. Morales; D. Scharf

2007-01-01

169

A simple 5-DoF MR-compatible motion signal measurement system.  

PubMed

The purpose of this study was to develop a simple motion measurement system with magnetic resonance (MR) compatibility and safety. The motion measurement system proposed here can measure 5-DoF motion signals without deteriorating the MR images, and it has no effect on the intense and homogeneous main magnetic field, the temporal-gradient magnetic field (which varies rapidly with time), the transceiver radio frequency (RF) coil, and the RF pulse during MR data acquisition. A three-axis accelerometer and a two-axis gyroscope were used to measure 5-DoF motion signals, and Velcro was used to attach a sensor module to a finger or wrist. To minimize the interference between the MR imaging system and the motion measurement system, nonmagnetic materials were used for all electric circuit components in an MR shield room. To remove the effect of RF pulse, an amplifier, modulation circuit, and power supply were located in a shielded case, which was made of copper and aluminum. The motion signal was modulated to an optic signal using pulse width modulation, and the modulated optic signal was transmitted outside the MR shield room using a high-intensity light-emitting diode and an optic cable. The motion signal was recorded on a PC by demodulating the transmitted optic signal into an electric signal. Various kinematic variables, such as angle, acceleration, velocity, and jerk, can be measured or calculated by using the motion measurement system developed here. This system also enables motion tracking by extracting the position information from the motion signals. It was verified that MR images and motion signals could reliably be measured simultaneously. PMID:21487903

Chung, Soon-Cheol; Kim, Hyung-Sik; Yang, Jae-Woong; Lee, Su-Jeong; Choi, Mi-Hyun; Kim, Ji-Hye; Yeon, Hong-Won; Park, Jang-Yeon; Yi, Jeong-Han; Tack, Gye-Rae

2011-09-01

170

Single-computer HWIL simulation facility for real-time vision systems  

NASA Astrophysics Data System (ADS)

UBM is working on autonomous vision systems for aircraft for more than one and a half decades by now. The systems developed use standard on-board sensors and two additional monochrome cameras for state estimation of the aircraft. A common task is to detect and track a runway for an autonomous landing approach. The cameras have different focal lengths and are mounted on a special pan and tilt camera platform. As the platform is equipped with two resolvers and two gyros it can be stabilized inertially and the system has the ability to actively focus on the objects of highest interest. For verification and testing, UBM has a special HWIL simulation facility for real-time vision systems. Central part of this simulation facility is a three axis motion simulator (DBS). It is used to realize the computed orientation in the rotational degrees of freedom of the aircraft. The two-axis camera platform with its two CCD-cameras is mounted on the inner frame of the DBS and is pointing at the cylindrical projection screen with a synthetic view displayed on it. As the performance of visual perception systems has increased significantly in recent years, a new, more powerful synthetic vision system was required. A single Onyx2 machine replaced all the former simulation computers. This computer is powerful enough to simulate the aircraft, to generate a high-resolution synthetic view, to control the DBS and to communicate with the image processing computers. Further improvements are the significantly reduced delay times for closed loop simulations and the elimination of communication overhead.

Fuerst, Simon; Werner, Stefan; Dickmanns, Ernst D.

1998-07-01

171

Clustered engine study  

NASA Astrophysics Data System (ADS)

Several topics are presented in viewgraph form which together encompass the preliminary assessment of nuclear thermal rocket engine clustering. The study objectives, schedule, flow, and groundrules are covered. This is followed by the NASA groundrules mission and our interpretation of the associated operational scenario. The NASA reference vehicle is illustrated, then the four propulsion system options are examined. Each propulsion system's preliminary design, fluid systems, operating characteristics, thrust structure, dimensions, and mass properties are detailed as well as the associated key propulsion system/vehicle interfaces. A brief series of systems analysis is also covered including: thrust vector control requirements, engine out possibilities, propulsion system failure modes, surviving system requirements, and technology requirements. An assessment of vehicle/propulsion system impacts due to the lessons learned are presented.

Shepard, Kyle; Sager, Paul; Kusunoki, Sid; Porter, John; Campion, Al; Mouritzan, Gunnar; Glunt, George; Vegter, George; Koontz, Rob

172

Accommodating electric propulsion on SMART-1  

NASA Astrophysics Data System (ADS)

This paper focuses on the technical challenges that arise when electric propulsion is used on a small spacecraft such as SMART-1. The choice of electric propulsion influences not only the attitude control system and the power system, but also the thermal control as well as the spacecraft structure. A description is given on how the design of the attitude control system uses the possibility to control the alignment of the thrust vector in order to reduce the momentum build-up. An outline is made of the philosophy of power generation and distribution and shows how the thermal interfaces to highly dissipating units have been solved. Areas unique for electric propulsion are the added value of a thrust vector orientation mechanism and the special consideration given to the electromagnetic compatibility. SMART-1 is equipped with a thruster gimbal mechanism providing a 10° cone in which the thrust vector can be pointed. Concerning the electromagnetic compatibility, a discussion on how to evaluate the available test results is given keeping in mind that one of the main objectives of the SMART-1 mission is to assess the impact of electric propulsion on the scientific instruments and on other spacecraft systems. Finally, the assembly, integration and test of the spacecraft is described. Compared to traditional propulsion systems, electric propulsion puts different requirements on the integration sequence and limits the possibilities to verify the correct function of the thruster since it needs high quality vacuum in order to operate. Prime contractor for SMART-1 is the Swedish Space Corporation (SSC). The electric propulsion subsystem is procured directly by ESA from SNECMA, France and is delivered to SSC as a customer furnished item. The conclusion of this paper is that electric propulsion is possible on a small spacecraft, which opens up possibilities for a new range of missions for which a large velocity increment is needed. The paper will also present SMART-1 and show how the problems related to the accommodation of electric propulsion have been solved during design and planning of the project.

Kugelberg, Joakim; Bodin, Per; Persson, Staffan; Rathsman, Peter

2004-07-01

173

International Symposium on Air Breathing Engines, 8th, Cincinnati, OH, June 14-19, 1987, Proceedings  

SciTech Connect

The present conference on air-breathing aircraft engine technology considers topics in inlet design, radial-flow turbomachinery, fuel injection and combustion systems, axial flow compressor design and performance, ramjet configurations, turbine flow phenomena, engine control and service life, fluid flow-related problems, engine diagnostic methods, propfan design, combustor performance and pollutant chemistry, combustion dynamics, and engine system analysis. Attention is given to thrust-vectoring systems, supersonic missile air intakes, three-dimensional centrifugal compressors, airblast atomizers, secondary flows in axial flow compressors, axial compressor blade tip clearance flows, hydrogen scramjets with sidewall injection, the performance of a variable-geometry turbine, advanced tip clearance control systems, rotary jet mixing, fan blade aeroelastic behavior, flow dynamics in combustion processes, and the technology of low cost turbomachinery.

Billig, F.S.

1987-01-01

174

Systeme multifonctions. (Multifunction system).  

National Technical Information Service (NTIS)

The development, the characteristics and the applications of a multifunction system are presented. The system is used on the RBES laboratory pipes, at Marcoule. The system was developed in order to allow, without time loss, the modification of the circuit...

J. Wauthier R. Fiori

1990-01-01

175

Home-built integrated microarray system (IMAS). A three-laser confocal fluorescence scanner coupled with a microarray printer.  

PubMed

Microarray technology covers the urgent need to exploit the accumulated genetic information from large-scale sequencing projects and facilitate investigations on a genome-wide scale. Although most applications focus on DNA microarrays, the technology has expanded to microarrays of proteins, peptides, carbohydrates, and small molecules aiming either at detection/quantification of biomolecules or investigation of biomolecular interactions in a massively parallel manner. Microarray experiments require two specialized instruments: An arrayer (or printer), for construction of microarrays, and a readout instrument (scanner). We have designed, constructed, and characterized the first integrated microarray system (IMAS) that combines the functions of a microarrayer and a three-laser confocal fluorescence scanner into a single instrument and provides excellent flexibility for the researcher. The three-axis robotic system that moves the printing head carrying multiple pins for arraying is also used for moving the microarray slide in front of a stationary optical system during scanning. Since the translation stages are the most expensive and crucial components of microarray printers and scanners, the proposed design reduces considerably the cost of the instrument and enhances remarkably its operative flexibility. Experiments were carried out at resolutions of 2.5, 5, 10, and 20 microm. The scanner detects 0.128 nmol L(-1) carboxyfluorescein (spots with diameters of 70 microm) corresponding to 1.8 molecules microm(-2). The linear range extends over 3.5 orders of magnitude (R(2) = 0.997) and the dynamic range covers almost five orders of magnitude. DNA microarray model experiments were carried out, including staining with SYBR Green I and hybridization with oligonucleotides labeled with the fluorescent dyes Alexa 488, Alexa 594, and Alexa 633. PMID:18228007

Tragoulias, Sotirios S; Obeid, Pierre J; Tataridis, Ioannis E; Christopoulos, Theodore K

2008-01-29

176

Inertial upper stage - Upgrading a stopgap proves difficult  

NASA Astrophysics Data System (ADS)

The technological and project management difficulties associated with the Inertial Upper Stage's (IUS) development and performance to date are assessed, with a view to future prospects for this system. The IUS was designed for use both on the interim Titan 34D booster and the Space Shuttle Orbiter. The IUS malfunctions and cost overruns reported are substantially due to the system's reliance on novel propulsion and avionics technology. Its two solid rocket motors, which were selected on the basis of their inherent safety for use on the Space Shuttle, have the longest burn time extant. A three-dimensional carbon/carbon nozzle throat had to be developed to sustain this long burn, as were lightweight composite wound cases and shirts, insulation, igniters, and electromechanical thrust vector control.

Geddes, J. P.

177

Advanced electric motor technology: Flux mapping  

NASA Astrophysics Data System (ADS)

This report contains the assumptions, mathematical models, design methodology, and design points involved with the design of an electromechanical actuator (EMA) suitable for directing the thrust vector of a large MSFC/NASA launch vehicle. Specifically the design of such an actuator for use on the upcoming liquid fueled National Launch System (NLS) is considered culminating in a point design of both the servo system and the electric motor needed. A major thrust of the work is in selecting spur gear and roller screw reduction ratios to achieve simultaneously wide bandwidth, maximum power transfer, and disturbance rejection while meeting specified horsepower requirements at a given stroking speed as well as a specified maximum stall force. An innovative feedback signal is utilized in meeting these diverse objectives.

Doane, George B., III; Campbell, Warren; Brantley, Larry W.; Dean, Garvin

1992-04-01

178

Autonomous Operation of the Nanosatellite URSA MAIOR Micropropulsion System  

NASA Astrophysics Data System (ADS)

Università degli Studi di Roma "La Sapienza", Scuola di Ingegneria Aerospaziale, Via Eudossiana 16, 00184 At Università di Roma "La Sapienza" a nanosatellite bus is under development, with one liter target volume and one kilogram target weight. This nanosatellite, called URSA MAIOR (Università di Roma "la SApienza" Micro Autonomous Imager in ORbit) has a micro camera on board to take pictures of the Earth. The nanosatellite is three axis stabilized, using a micro momentum wheel, with magnetic coils for active nutation damping and pointing control. An experimental micropropulsion system is present on-board, together with the magnetic attitude control system. The design, construction and testing of the satellite is carried on by academic personnel and by students, which are directly involved in the whole process, as it is in the spirit of in the microsatellite program at Università di Roma "La Sapienza". Few technological payloads are present on-board: an Earth imaging experiment, using a few grams commercial-off-the-shelf microcamera; commercial Li-Ion batteries are the only energy storage device; a microwheel developed at our University laboratories provides for attitude stabilization. In addition, a micropropulsion experiment is planned on-board. The Austrian Company Mechatronic, and INFM, an Italian Research Institute at Trieste are developing a microthruster for nanosatelite applications. In the frame of a cooperation established between these two Institutions and Università di Roma "La Sapienza", this newly developed hardware will be tested in orbit. The thruster is made basically of an integrated microvalve, built on a silicon chip, and a micronozzle, etched on the same silicon chip, to get supersonic expansion of the gas flow. The nominal thrust of the system is about 100microN. The throat section is about 100 micron diameter. The first phase in the construction of the microthruster has been the construction of the micronozzle on a silicon chip. A micropropulsion system realized with this micronozzle and with commercial valves, not integrated on a silicon chip, will be tested on board the microsatelite UNISAT-2, to be launched within 2002. A step further with respect to the system configuration to be flown on UNISAT-2 is the miniaturized microvalve, allowing to reduce the system volume and weight. As a matter of fact, the complete micropropulsion system fits in the one liter nanosatellite URSA MAIOR attitude control needs. The microvalve and nozzle occupy few squared millimiters of the external satellite surface, while the gas tank is about one tenth of the nanosatellite volume. One of the goals of the experiment is testing the micropropulsion hardware in space and assessing the microthruster performance in orbit. Another part of the experiment is devoted to the use of the micropropulsion system for autonomous spacecraft attitude maneuvers. One of these is the momentum wheel desaturation. When using the magnetic desaturation, some commands are sent to the satellite in order to perform the maneuver in the most efficient part of the orbit, depending on the magnetic field direction. When the micropropulsion system is active, the maneuver is performed autonomously, without any intervention from the ground. The on-board system monitors the maneuver evolution and stops when the maneuver is complete, sending a message to the ground station. To evaluate the autonomous system performance, attitude telemetry is stored during the maneuver and downloaded to the ground station. In the paper the nanosatellite URSA MAIOR is briefly described. The micropropulsion system is shown in detail and the ground test results discussed. The attitude control hardware is described and the numerical simulation results of the micropropulsion maneuvers described. Particular attention is given to the telemetry analysis performed autonomously on-board to make decision about the maneuver success.

Santoni, F.

179

Attitude determination and control system simulation and analysis for low-cost micro-satellites  

Microsoft Academic Search

The Air Force Academy's latest satellite endeavor, FalconSAT-3, is a 50 kg microsatellite being developed by faculty and cadets, and is the Air Force Academy's first attempt at achieving three axis attitude determination and control (ADCS). FalconSAT-3 carries three payloads to conduct DoD research. The attitude requirements for FalconSAT-3 include pointing the satellite within +\\/- five degrees of ram direction,

Andrew D. Anderson; Jerry J. Sellers; Yoshi Hashida

2004-01-01

180

Integrated attitude determination and control system via magnetic measurements and actuation  

Microsoft Academic Search

A nonlinear control scheme using a Modified State-Dependent Riccati Equation (MSDRE) is developed through a pseudo-linearization of spacecraft augmented nonlinear dynamics and kinematics. The full-state knowledge required for the control loop is provided through a generalized algorithm for spacecraft three-axis attitude and rate estimation based on the utilization of magnetometer measurements and their time derivatives, while the control torque is

Mohammad Abdelrahman; Sang-Young Park

2011-01-01

181

Attitude determination and control system simulation and analysis for low-cost micro-satellites  

Microsoft Academic Search

The Air Force Academy's latest satellite endeavor, FalconSAT-3, is a 50 kg microsatellite being developed by faculty and cadets, and is the Air Force Academy's first attempt at achieving three axis attitude determination and control (ADCS). FalconSAT-3 will carry three payloads to conduct DoD research. The attitude requirements for FalconSAT-3 include pointing the satellite within +\\/- five degrees of ram

Andrew D. Anderson; Jerry I. Sellers; Yoshi Hashida

2004-01-01

182

Immune System  

MedlinePLUS

... could put us out of commission. What the Immune System Does The immune (pronounced: ih- myoon ) system, which ... Continue Things That Can Go Wrong With the Immune System Disorders of the immune system can be broken ...

183

Design of a ZVS PWM Inverter for a Brushless DC Motor in an EMA Application.  

National Technical Information Service (NTIS)

The Component Development Division of the Propulsion Laboratory at Marshall Space Flight Center (MSFC) is currently investigating the use of electromechanical actuators for use in space transportation applications such as Thrust Vector Control (TVC). Thes...

J. B. Bell R. M. Nelms M. T. Shepherd

1993-01-01

184

Time-Optimization of High Performance Combat Maneuvers.  

National Technical Information Service (NTIS)

Recent developments in post-stall maneuverability and thrust vectoring have opened up new possibilities in the field of air combat maneuvering. High angle of attack maneuvers like the Cobra, Herbst Reversal, and Chakra demonstrate that today's cutting edg...

B. R. Carter

2005-01-01

185

Dynamical System  

Microsoft Academic Search

SUMMARY This paper addresses the parameter estimation problem of an interval-based hybrid dynamical system (interval system). The interval system has a two-layer architecture that comprises a finite state automaton and multiple linear dynam- ical systems. The automaton controls the activation timing of the dynamical systems based on a stochastic transition model between intervals. Thus, the interval system can generate and

Takashi MATSUYAMA

186

Aerospace Systems  

NSDL National Science Digital Library

This pdf contains a syllabus for a course on aerospace systems as part of the Aerospace Technology Program. This course covers an introduction to expendable and reusable Space Launch Vehicle (SLV) systems including hydraulic, pneumatic, electrical, propulsion, mechanical, HVAC (heating, ventilation and air conditioning), and ECLSS (Environmental Control and Life Support Systems). How systems interact with computer and data acquisition systems is also covered.

2011-08-11

187

Aesthetics Systems.  

National Technical Information Service (NTIS)

The formal structure of aesthetics systems is defined. Aesthetics systems provide for the essential tasks of interpretation and evaluation is aesthetic analysis. Kolmogorov's formulation of information theory is applicable. An aesthetics system for a clas...

J. Gips G. Stiny

1973-01-01

188

Rebreathing System.  

National Technical Information Service (NTIS)

The patent application is a constant volume rebreathing system when utilized in conjunction with an external air source, such as man. The rebreathing system forms a completely closed system between man and the environment. There is a stainless steel bello...

J. P. Conkle

1974-01-01

189

Systems Studies.  

National Technical Information Service (NTIS)

The Systems Studies Activity had two objectives: (1) to investigate nontechnical barriers to the deployment of biomass production and supply systems and (2) to enhance and extend existing systems models of bioenergy supply and use. For the first objective...

R. L. Graham

1998-01-01

190

Ensuring Dependable Systems of Systems  

Microsoft Academic Search

The emerging class of systems known as Systems of Systems (SoS) are composed of many distributed, heterogeneous and autonomous components. Such systems are typically separately designed and manufactured and evolve throughout their lifetime. However, they are expected to work together, often in safety-critical areas of operation such as civil transportation, military operations and space exploration. As such, the systems are

Robert Alexander; Martin Hall-May; Tim Kelly

191

Systems thinking or systems engineering  

Microsoft Academic Search

The problem faced by most systems organisations is how to develop and sustain staff with the appropriate systems skills and experience. To date, much has been made of the delineation of systems thinking and systems engineering. In this research, the partitioning of \\

Kate M. Gill

2009-01-01

192

Solar System  

NSDL National Science Digital Library

At the end of this project, you will be able to explain the components of the Solar System and know the order of the planets starting from the Sun. Objective Question: What is the Solar System? First, listen and read about the Solar System 1. How many planets make up our Solar System? 2. What is at the center of the Solar System? Next,listen and read about the Planets. 1. Can you name all of the planets? Finally, listen and watch The Solar System Movie. 1. Can you list the ...

Ms.west

2009-07-07

193

Stimulator system  

SciTech Connect

An electrical stimulator system is described incorporating rechargeable batteries and a charging circuit. A charging set and electrode support are alternatively connected to the stimulator system via a single common two-pole terminal. The system is designed to prevent current from flowing directly from the battery to the electrode support along the charging circuit while allowing charge current to flow in the opposite direction along the charging circuit if the charging set is connected to the system instead of the electrode support.

Hakansson, B.H.; Saario, R.A.

1984-02-14

194

Energy Systems  

NSDL National Science Digital Library

Posters are provided for several different energy conversion systems. Students are provided with cards that give the name and a description of each of the components in an energy system. They match these with the figures on the diagram. Since the groups look at different systems, they also describe their results to the class to share their knowledge.

Office Of Educational Partnerships

195

Systems Liaisons  

Microsoft Academic Search

As computer technology increases its role within academic libraries, one of the problems faced by systems librarians is maintaining the equipment and training needed for the technology without overworking the library's systems staff. This article describes the development of a group of systems liaisons within an academic library to serve as front line managers for computer hardware, software, and simpler

Pam Burton; Margaret Foote

2000-01-01

196

Solar System  

NSDL National Science Digital Library

An introduction to to the solar system. How to distinguish between the different planets. Activities to play while getting to know the solar system. Cosmic Cookies Solar System Scavenger Hunt Edible Earth Strawkets and Control Strawkets and Thrust Strawkets and Weight ...

Wright, Ms.

2009-10-09

197

Systems biotechnology.  

PubMed

Systems biology has been changing the way biological and biotechnological research is performed. Now, systems biological approaches can be taken to develop bioprocesses for the production of valuable drugs, commodity and fine chemicals, fuels, and polymers and other materials; this is termed systems biotechnology. Here I present the general strategies for systems biotechnology and several examples of applying systems biotechnological strategies for the development of bioprocesses for the efficient production of chemicals and materials. This also includes a strategy of systems metabolic engineering for the development of microbial strains. It is expected that systems biotechnology will be at the heart of successful industrial biotechnology towards low carbon green growth of the world. PMID:20180277

Lee, Sang Yup

2009-10-01

198

Micropower system  

SciTech Connect

A micropower DC/DC conversion system is disclosed providing a stabilized voltage output at a predetermined voltage higher than that of the energy source. The system is powered by one or more primary cells in parallel or by a suitable battery, and the system is of special use with systems requiring low power at stabilized voltage which is substantially independent of the energy source impedance and load variations. According to the preferred embodiment of the system the output voltage stabilization is controlled by voltage detection circuit based on C-MOS inverters which allows extremely low power drain. The system is of special value for use with electronic implantable devices such as cardiac pacemakers.

Krupka, Y.; Bachar, A.; Yerushalmi, S.

1983-11-01

199

Autogeneric system  

US Patent & Trademark Office Database

The invention of the "autogeneric system" in the form of <> is a closed recursive manufacturing cycle. Present technology is probably sufficient to build fifth generation computing systems, but the actual construction of inductive and deductive logic machines awaits the discovery of real methods. The working model <> operates by the relentless application of directed trial and error. The operation of <> has been directed to produce "better" versions of <>. The copyrighted version of <> can be used to manufacture microcomputer systems, and process control systems. The value of "autogeneric systems" rests in the inherent ability to create or manufacture complex systems on demand. The ability to incorporate expert knowledge into reusable modules allows a multiplication of the efforts of experts. The error detection allows real telecommunications networks to be used to create a distributed computer.

Davis; Dannie E. (Elmore, AL)

1988-03-29

200

Operating Systems  

NSDL National Science Digital Library

Rashid Bin Muhammad at Kent State University presents his page of lectures notes and other instructional materials on operating systems. The site is divided into a number of topics about operating systems: history, structure, process, threads, Solaris-2, CPU / process scheduling, schedule algorithm, interprocess communication, deadlock, important UNIX commands, and references. The site is then followed by links to outside resources to help supplement the material presented here. This is a great resource for computer science instructors teaching students about operating systems.

Bin Muhammad, Rashid

2009-06-24

201

Serials Systems  

Microsoft Academic Search

The criteria for selecting a serials management system are often the same as those for selecting an integrated library system in toto. In the post-selection\\/production environment, the library–vendor relationship matures as a new operational framework is established. Serials management systems must become more efficient and make better use of electronic commerce, especially as a greater emphasis is placed on access

Pamela Bluh; Marc Truitt; Bob Boissy

2002-01-01

202

CALUTRON SYSTEM  

DOEpatents

A calutron system capable of functioning with only a portion of the separation tanks in the system operating is described. The invention is a calutron system comprssing a closed series of alternated tanks and electromagnets having a mid-yoke connecting intermediate positions of the series. dividing the series into twv-o portions, and thereby providing a closed magnetic path through either of the portions.

Lawrence, E.O.

1958-08-12

203

Systemic Darwinism  

PubMed Central

Darwin's 19th century evolutionary theory of descent with modification through natural selection opened up a multidimensional and integrative conceptual space for biology. We explore three dimensions of this space: explanatory pattern, levels of selection, and degree of difference among units of the same type. Each dimension is defined by a respective pair of poles: law and narrative explanation, organismic and hierarchical selection, and variational and essentialist thinking. As a consequence of conceptual debates in the 20th century biological sciences, the poles of each pair came to be seen as mutually exclusive opposites. A significant amount of 21st century research focuses on systems (e.g., genomic, cellular, organismic, and ecological/global). Systemic Darwinism is emerging in this context. It follows a “compositional paradigm” according to which complex systems and their hierarchical networks of parts are the focus of biological investigation. Through the investigation of systems, Systemic Darwinism promises to reintegrate each dimension of Darwin's original logical space. Moreover, this ideally and potentially unified theory of biological ontology coordinates and integrates a plurality of mathematical biological theories (e.g., self-organization/structure, cladistics/history, and evolutionary genetics/function). Integrative Systemic Darwinism requires communal articulation from a plurality of perspectives. Although it is more general than these, it draws on previous advances in Systems Theory, Systems Biology, and Hierarchy Theory. Systemic Darwinism would greatly further bioengineering research and would provide a significantly deeper and more critical understanding of biological reality.

Winther, Rasmus Gr?nfeldt

2008-01-01

204

Anticipatory systems as linguistic systems  

NASA Astrophysics Data System (ADS)

The idea of system is well established although not well defined. What makes up a system depends on the observer. Thinking in terms of systems is only a convenient way to conceptualize organizations, natural or artificial, that show coherent properties. Among all properties, which can be ascribed to systems, one property seems to be more outstanding than others, namely that of being anticipatory. In nature, anticipatory properties are found only in living organizations. In this way it can be said to separate non-living systems from living because there is no indication that any natural phenomenon occurring in systems where there is no indication of life is anticipatory. The characteristic of living systems is that they are exposed to the evolution contrary to causal systems that do not undergo changes due to the influence of the environment. Causal systems are related to the past in such a way that subsequent situations can be calculated from knowledge of past situations. In causal systems the past is the cause of the present and there is no reference to the future as a determining agent, contrary to anticipatory systems where expectations are the cause of the present action. Since anticipatory properties are characteristic of living systems, this property, as all other properties in living systems, is a result of the evolution and can be found in plants as well as in animals. Thus, it is not only tied to consciousness but is found at a more basic level, i.e., in the interplay between genotype and phenotype. Anticipation is part of the genetic language in such a way that appropriate actions, for events in the anticipatory systems environment, are inscribed in the genes. Anticipatory behavior, as a result of the interpretation of the genetic language, has been selected by the evolution. In this paper anticipatory systems are regarded as linguistic systems and I argue that as such anticipation cannot be fragmented but must be holistically studied. This has the implication that anticipatory behavior can only partially be described in a computer language and, furthermore, it shows that only a restricted class of anticipatory systems can be transferred to computers. .

Ekdahl, Bertil

2000-05-01

205

Systems Thinking  

NSDL National Science Digital Library

This video from SpaceTEC National Aerospace Technical Education Center explains the General Systems Model and how consider the entire system when performing aerospace work. This three and a half minute video is one of the aerospace certification readiness courses.

2011-07-27

206

ECONOMIC SYSTEMS  

NSDL National Science Digital Library

The information you will explore is: List and categorize the four main types of Economic Systems in our world today. Create graphic Illustrations of thoughts and concepts. Express how economic system structures effect the lives of the people living in that system. Write to express an opinion or point of view. Experience a simulation of the marketplace. Research a country of your choice and find important factors about their economic system. Each country structures their economic system after one of the four main types or a combination of these. The assignments on this page will help you to gain a better understanding of the characteristics of the four main types of economic systems. Process: 1. Click on the following link Marketing Calendar Open the Global Economy power point. Use the Chapter 4 listening guide with the power point. chap4 listening guide 2. List the four main economic systems and find the main characterisitics of each. Compare strengths and weaknesses of each. Economic Systems Characteristics 3.Create a ...

Mrs.owen

2006-10-10

207

Propulsion System.  

National Technical Information Service (NTIS)

The closed cycle propulsion system for a torpedo uses aluminum as a source of hydrogen. The system includes a fuel generator, a store of oxidizer, a combustion chamber, a steam-driven prime mover, a condenser and three displacement pumps driven by a commo...

N. Fatica

1966-01-01

208

Heating system  

Microsoft Academic Search

A method for recovering waste heat from heating system exhaust gas is described. In a heating system located in a furnace room and including a furnace and an air blower for delivering air to the furnace via an inlet stack and heating pipes for the delivery of heated air from the furnace to the areas to be heated, the improvement

Anable

1975-01-01

209

Decimal system  

NSDL National Science Digital Library

Early scientific efforts by the Chinese yielded the decimal system. The Chinese were mostly known for their physical inventions during this time, so it was unusual to see something like the decimal system come from China at this point in history.

N/A N/A (None;)

2007-10-24

210

Systems Librarianship  

NSDL National Science Digital Library

The SYSLIB-L list serves as a vehicle for the discussion of topics related to systems librarianship and for the collection of information related to systems librarianship. Postings may include, but are not limited to, job postings, technical questions, philosophical discussions, and education.

1997-01-01

211

Organ Systems  

NSDL National Science Digital Library

This "Organ Systems" module has five units of instruction that focus on the main classes of functions that a body must perform. Rather than just naming organs of the body and what they do, they present a perspective on the body as a coordinated group of systems that must do certain things correctly in order to survive and thrive.

Klemm, W. R.

2001-01-01

212

System Toolbox  

NSDL National Science Digital Library

System Toolbox is designed for system administrators who deal with a variety of platforms. The site covers Windows NT, General Unix, Novell, Linux, Solaris, HP-UX, and the Mac OS. The "toolbox" for each platform offers annotated links to Tools (Disk Management, Anti-Virus, Security, etc.), Articles, and other useful Links. While the information here is hardly comprehensive, the site offers useful, if often basic, resources for administrators. System Toolbox's brand new History section looks promising, with two articles currently posted, "Von Braun's Slide Rule" and "The Godfather of Computing - Charles Babbage." The Comments section allows users to post questions or comments.

2001-01-01

213

Systems and Components Fuel Delivery System, Water Delivery System, ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Systems and Components - Fuel Delivery System, Water Delivery System, Derrick Crane System, and Crane System Details - Marshall Space Flight Center, F-1 Engine Static Test Stand, On Route 565 between Huntsville and Decatur , Huntsville, Madison County, AL

214

SAMPLING SYSTEM  

DOEpatents

An apparatus is given for the batch sampling of radioactive liquids such as slurries from a system by remote control, while providing shielding for protection of operating personnel from the harmful effects of radiation.

Hannaford, B.A.; Rosenberg, R.; Segaser, C.L.; Terry, C.L.

1961-01-17

215

Root systems  

NSDL National Science Digital Library

One purpose that roots serve is that of anchoring the plant in the ground. Roots also take up water and nutrients for the plant. Plants all have different root system types to fit their individual needs and locations.

N/A N/A (U.S. Government;)

2004-10-30

216

Digestive System  

MedlinePLUS

... remove inflamed or damaged areas of the intestine. Celiac disease is a disorder in which the digestive system ... from breakfast cereal to pizza crust. People with celiac disease have difficulty digesting the nutrients from their food ...

217

Respiratory System  

NSDL National Science Digital Library

The purpose, components, and functions of the respiratory system are presented in this learning through disussion and visualizations. Participants learn about the nasal cavity, pharynx, larynx, trachea, bronchi, bronchioles, and alveoli.

Bidlack, Jim

218

Embedded Systems  

NSDL National Science Digital Library

Embedded systems are dedicated computers designed to perform a specific task. They are usually fairly simple devices that are used in areas where powerful, customizable computers are unnecessary; however, they can also be quite complex on occasion. Embedded systems can be found almost anywhere, including automobiles and cellular phones, and their importance is reflected in their near omnipresence.An excellent introduction to embedded systems can be found in the first three pages of this online course material (1). The educational module gives a thorough definition of embedded systems, several examples of where they are used, and a discussion of their common components. For a more detailed explanation of how these devices are used to control various appliances, motors, and other real world products, this site (2) is worth a visit. Sixteen sections comprise the site, and each includes background information and an example experiment. Although certain equipment is required for the experiments, much can be learned simply from reading the introductions. This enlightening essay (3) documents the history and development of embedded systems. Despite being somewhat specific to the author's life, it effectively illustrates the evolution of embedded systems and their incorporation into many facets of everyday life. A paper presented at the 2003 International Cryptology Conference (4) considers the vulnerability of embedded cryptosystems to side channel attacks, which are different from normal security violations because they involve monitoring parts of the hardware system instead of the software. The authors propose the design of private circuits that are resistant to such attacks. The Center for Robotics and Embedded Systems at the University of Southern California is the source of this paper (5) about networked robots. Although it is somewhat dated, the paper provides some valuable insights into how robots can be used in human environments and how they can be controlled and coordinated with wireless communications. An article from Dedicated Systems Magazine (6) highlights the role of embedded systems in NASA's Mars Exploration Rovers, which were launched in June and July 2003. The technologies that enabled the rovers to have powerful, reliable operation are described. The April 2003 issue of ACM Queue (7), the online magazine of the Association for Computing Machinery, is dedicated to embedded systems. Seven articles are included in the issue, dealing with the design and construction process of embedded devices and the hardware/software interface. Lastly, a short paper that was presented at a computer architecture symposium in January 2003 looks ahead to the realization of ubiquitous computing (8). This technology revolution, which has been predicted for many years, promises to make tiny computers embedded in virtually everything, even clothing and walls. The author focuses on the area of intelligent vehicles and wheeled mobile robots.

Leske, Cavin.

219

System Dynamics  

Microsoft Academic Search

\\u000a System dynamics is an approach for thinking about and simulating situations and organisations of all kinds and sizes by visualising\\u000a how the elements fit together, interact and change over time. This chapter, written by John Morecroft, describes modern system\\u000a dynamics which retains the fundamentals developed in the 1950s by Jay W. Forrester of the MIT Sloan School of Management.\\u000a It

John Morecroft

2010-01-01

220

Scoring systems  

Microsoft Academic Search

Severity of illness scoring systems are helpful for defining populations of critically ill patients because they facilitate,\\u000a for example, comparison of different groups of patients enrolled in clinical trials. Such scoring systems may also guide more\\u000a effective allocation of resources, such as nursing and ancillary care and help in assessing the quality of care in the intensive\\u000a care unit (ICU)

John Kress

221

Systems Studies  

SciTech Connect

The Systems Studies Activity had two objectives: (1) to investigate nontechnical barriers to the deployment of biomass production and supply systems and (2) to enhance and extend existing systems models of bioenergy supply and use. For the first objective, the Activity focused on existing bioenergy markets. Four projects were undertaken: a comparative analysis of bioenergy in Sweden and Austria; a one-day workshop on nontechnical barriers jointly supported by the Production Systems Activity; the development and testing of a framework for analyzing barriers and drivers to bioenergy markets; and surveys of wood pellet users in Sweden, Austria and the US. For the second objective, two projects were undertaken. First, the Activity worked with the Integrated BioEnergy Systems (TBS) Activity of TEA Bioenergy Task XIII to enhance the BioEnergy Assessment Model (BEAM). This model is documented in the final report of the IBS Activity. The Systems Studies Activity contributed to enhancing the feedstock portion of the model by developing a coherent set of willow, poplar, and switchgrass production modules relevant to both the US and the UK. The Activity also developed a pretreatment module for switchgrass. Second, the Activity sponsored a three-day workshop on modeling bioenergy systems with the objectives of providing an overview of the types of models used to evaluate bioenergy and promoting communication among bioenergy modelers. There were nine guest speakers addressing different types of models used to evaluate different aspects of bioenergy, ranging from technoeconomic models based on the ASPEN software to linear programming models to develop feedstock supply curves for the US. The papers from this workshop have been submitted to Biomass and Bioenergy and are under editorial review.

Graham, R.L.

1998-03-17

222

System of Hungarian System Management.  

National Technical Information Service (NTIS)

The new disaster management direction and responsibility system and the professional disaster management organization were tested last year in practice. Perhaps liquidation of consequences of terrorist acts was the only threat, which it did not need to fa...

L. Kozari

2001-01-01

223

FDA Industry Systems - System Status  

Center for Food Safety and Applied Nutrition (CFSAN)

... November 14, 2009: ESG Pre-Production (Test) system was unavailable from 6:00pm November 13, 2009 EST to 11:59pm November 14, 2009 EST ... More results from www.fda.gov/food/guidanceregulation/foodfacilityregistration

224

Feasibility of small animal cranial irradiation with the microRT system  

SciTech Connect

Purpose: To develop and validate methods for small-animal CNS radiotherapy using the microRT system. Materials and Methods: A custom head immobilizer was designed and built to integrate with a pre-existing microRT animal couch. The Delrin couch-immobilizer assembly, compatible with multiple imaging modalities (CT, microCT, microMR, microPET, microSPECT, optical), was first imaged via CT in order to verify the safety and reproducibility of the immobilization method. Once verified, the subject animals were CT-scanned while positioned within the couch-immobilizer assembly for treatment planning purposes. The resultant images were then imported into CERR, an in-house-developed research treatment planning system, and registered to the microRTP treatment planning space using rigid registration. The targeted brain was then contoured and conformal radiotherapy plans were constructed for two separate studies: (1) a whole-brain irradiation comprised of two lateral beams at the 90 degree sign and 270 degree sign microRT treatment positions and (2) a hemispheric (left-brain) irradiation comprised of a single A-P vertex beam at the 0 degree sign microRT treatment position. During treatment, subject animals (n=48) were positioned to the CERR-generated treatment coordinates using the three-axis microRT motor positioning system and were irradiated using a clinical Ir-192 high-dose-rate remote after-loading system. The radiation treatment course consisted of 5 Gy fractions, 3 days per week. 90% of the subjects received a total dose of 30 Gy and 10% received a dose of 60 Gy. Results: Image analysis verified the safety and reproducibility of the immobilizer. CT scans generated from repeated reloading and repositioning of the same subject animal in the couch-immobilizer assembly were fused to a baseline CT. The resultant analysis revealed a 0.09 mm average, center-of-mass translocation and negligible volumetric error in the contoured, murine brain. The experimental use of the head immobilizer added {+-}0.1 mm to microRT spatial uncertainty along each axis. Overall, the total spatial uncertainty for the prescribed treatments was {+-}0.3 mm in all three axes, a 0.2 mm functional improvement over the original version of microRT. Subject tolerance was good, with minimal observed side effects and a low procedure-induced mortality rate. Throughput was high, with average treatment times of 7.72 and 3.13 min/animal for the whole-brain and hemispheric plans, respectively (dependent on source strength). Conclusions: The method described exhibits conformality more in line with the size differential between human and animal patients than provided by previous prevalent approaches. Using pretreatment imaging and microRT-specific treatment planning, our method can deliver an accurate, conformal dose distribution to the targeted murine brain (or a subregion of the brain) while minimizing excess dose to the surrounding tissue. Thus, preclinical animal studies assessing the radiotherapeutic response of both normal and malignant CNS tissue to complex dose distributions, which closer resemble human-type radiotherapy, are better enabled. The procedural and mechanistic framework for this method logically provides for future adaptation into other murine target organs or regions.

Kiehl, Erich L.; Stojadinovic, Strahinja; Malinowski, Kathleen T.; Limbrick, David; Jost, Sarah C.; Garbow, Joel R.; Rubin, Joshua B.; Deasy, Joseph O.; Khullar, Divya; Izaguirre, Enrique W.; Parikh, Parag J.; Low, Daniel A.; Hope, Andrew J. [Washington University School of Medicine, St. Louis, Missouri 63110 (United States); Virginia Commonwealth University School of Medicine, Richmond, Virginia 23298 (United States); Washington University School of Medicine, St. Louis, Missouri 63110 (United States); Princess Margaret Hospital, Toronto, Ontario M5G 2M9 (Canada)

2008-10-15

225

Systemic fluoride.  

PubMed

There is substantial evidence that fluoride, through different applications and formulas, works to control caries development. The first observations of fluoride's effects on dental caries were linked to fluoride naturally present in the drinking water, and then from controlled water fluoridation programs. Other systemic methods to deliver fluoride were later suggested, including dietary fluoride supplements such as salt and milk. These systemic methods are now being questioned due to the fact that many studies have indicated that fluoride's action relies mainly on its post-eruptive effect from topical contact with the tooth structure. It is known that even the methods of delivering fluoride known as 'systemic' act mainly through a topical effect when they are in contact with the teeth. The effectiveness of water fluoridation in many geographic areas is lower than in previous eras due to the widespread use of other fluoride modalities. Nevertheless, this evidence should not be interpreted as an indication that systemic methods are no longer relevant ways to deliver fluoride on an individual basis or for collective health programs. Caution must be taken to avoid excess ingestion of fluoride when prescribing dietary fluoride supplements for children in order to minimize the risk of dental fluorosis, particularly if there are other relevant sources of fluoride intake - such as drinking water, salt or milk and/or dentifrice. Safe and effective doses of fluoride can be achieved when combining topical and systemic methods. PMID:21701196

Sampaio, Fábio Correia; Levy, Steven Marc

2011-06-23

226

Manufacturing Systems  

NSDL National Science Digital Library

Objective 7:05 - Students will develop an awareness of the designed World through : Describing a manufacturing system; listing and describing the basic type of manufacturing; defining production and manufacturing enterprise;defining AGV, CAD, CIM, CAM, CNC, production tooling, automation, and material processes. Day 1: Introduction/Background Objective Preassessment: Use a KWL chart to assess your students prior knowledge. This will also help you deal with any misconceptions regarding manufacturing system. Students will use the curriculum companion PowerPoint and Objective 7.05 Outline to develop an awarness of: Define manufacturing List and describe the basic types of Manufacturing Student ...

Wallace, S.

2010-07-16

227

System Overview  

NSDL National Science Digital Library

This is a description for a learning module from Maricopa Advanced Technology Education Center. This PDF describes the module; access may be purchased by visiting the MATEC website. Technicians face the challenge of building and maintaining knowledge and skills that are applicable to microcomputer architecture. These challenges include keeping up to date on improvements in PC components, changes in PC hardware configurations, integration of new devices within PC systems, and the ability to readily apply their knowledge within the microcomputer manufacturing industry. This module provides an introduction and overview to the major system features that define the architecture of an Intel-based PC. A unique multimedia self-tutorial is included.

2011-08-22

228

[Systemic scleroderma].  

PubMed

Systemic scleroderma is a chronic autoimmune disease affecting the skin, internal organs and the musculoskeletal system. The presence of Raynaud phenomenon, anti-nuclear antibodies and pathologic capillaroscopy are early signs of the disease. Limited cutaneous SSc, diffuse cutaneous SSc and SSc-overlap syndromes are the main clinical subtypes. Multidisciplinary care is mandatory. Follow-up examinations should be performed at least annually in order to recognize in a timely fashion treatable organ involvement such as pulmonary arterial hypertension. Besides symptomatic treatment of organ involvement, immunosuppressive therapy is indicated for a progressive inflammatory course. PMID:23576170

Hunzelmann, N

2013-04-01

229

Solar System  

NSDL National Science Digital Library

This site is part of the space page of the British Broadcasting Corporation (BBC), and provides information about the Sun, the planets and their moons, and other bodies in the solar system. It contains a travel guide to the Solar System including such topics as what to see, reason to visit, how to get there, and local history. A similar travel guide is then available for the Sun, each of the planets, asteroids, and comets. In addition, multiple links for more detailed information as well as space games and puzzles are provided.

2007-12-12

230

Rabbit System.  

National Technical Information Service (NTIS)

A rabbit system for ultrafast transport of a sampler between a sampling point and an analysis position is described. The sampler is transported pneumatically in a carrier capsule first to a sampling point and then to a separating structure in front of the...

1978-01-01

231

Telemetry system  

SciTech Connect

A telemetry system is descried for transmitting data between a downhole location in a wellbore and the surface of a well. It utilizes an acoustic signal which operates within naturally occurring passbands on a string of pipe and has substantially fixed frequency ranges which are related to pipe length and condition.

Chaney, P.E.; Cox, W.H.

1981-10-06

232

Immune System  

EPA Science Inventory

A properly functioning immune system is essential to good health. It defends the body against infectious agents and in some cases tumor cells. Individuals with immune deficiencies resulting from genetic defects, diseases (e.g., AIDS, leukemia), or drug therapies are more suscepti...

233

Windpower system  

Microsoft Academic Search

A windpower system includes a support and a turbine having a shaft rotatively mounted to the support. The turbine has variable pitch blades whose pitch is controlled by the differential motion of a rotary control shaft coaxial with the turbine shaft and the turbine shaft itself so that the blade pitch can be varied by a stationary motor without requiring

A. Chertok; J. Gjertsen Sr; L. Manfredi

1984-01-01

234

Nanoelectromechanical systems  

Microsoft Academic Search

Nanoelectromechanical systems (NEMS) are nano-to-micrometer scale mechanical resonators coupled to electronic devices of similar dimensions. NEMS show promise for fast, ultrasensitive force microscopy and for deepening our understanding of how classical dynamics arises by approximation to quantum dynamics. This article begins with a survey of NEMS and then describes certain aspects of their classical dynamics. In particular, we show that

Mp Blencowe

2005-01-01

235

System Dynamics  

NASA Astrophysics Data System (ADS)

System dynamics is an approach for thinking about and simulating situations and organisations of all kinds and sizes by visualising how the elements fit together, interact and change over time. This chapter, written by John Morecroft, describes modern system dynamics which retains the fundamentals developed in the 1950s by Jay W. Forrester of the MIT Sloan School of Management. It looks at feedback loops and time delays that affect system behaviour in a non-linear way, and illustrates how dynamic behaviour depends upon feedback loop structures. It also recognises improvements as part of the ongoing process of managing a situation in order to achieve goals. Significantly it recognises the importance of context, and practitioner skills. Feedback systems thinking views problems and solutions as being intertwined. The main concepts and tools: feedback structure and behaviour, causal loop diagrams, dynamics, are practically illustrated in a wide variety of contexts from a hot water shower through to a symphony orchestra and the practical application of the approach is described through several real examples of its use for strategic planning and evaluation.

Morecroft, John

236

Respiratory System  

MedlinePLUS

... Search Form Advanced Search Search the NHLBI, use radio buttons below to select whole site or Disease and Conditions Index only NHLBI Entire ... Information for the Public » Health Topics » How the Lungs Work » The Respiratory System How the Lungs Work Explore ...

237

POWER SYSTEMS  

Microsoft Academic Search

Low power output of other devices at this time dictates the use of ; nuclear-reactor systems for manned space explorations. Work up to the present is ; briefly reviewed, and progress and utilization of other power supplies are ; discussed. Pros and cons of solar cells, fuel cells, and thermoelectric and ; thermionic devices are included as well as consideration

1962-01-01

238

Optoelectronic system  

Microsoft Academic Search

Necessity of devices and systems for identity verification and individualization of security holograms (SH) is growing together with the growth of SH production. The hidden coded micro image as a set of points (bits) was chosen as a new security element. This image is separately added into hologram by laser perforation on the final stage of SH production after replication.

Dmitry Sergeevich Lushnikov; Sergey Borisovich Odinokov; Alexander Yurievich Pavlov

2011-01-01

239

Embedded Systems  

NSDL National Science Digital Library

The April 2003 issue of ACM Queue, the online magazine of the Association for Computing Machinery, is dedicated to embedded systems. Seven articles are included in the issue, dealing with the design and construction process of embedded devices, programming, and the hardware/software interface.

2008-02-08

240

Digestive System  

NSDL National Science Digital Library

This site contains a section of an online Biology Textbook - developed by Dr. Michael Gregory of Clinton Community College - providing a concise overview of the digestive system. It describes the enzymes, carbohydrates, proteins, and lipids involved in digestion and outlines the role that each part of the body plays from the mouth the large intestine.

Gregory, Michael

1969-12-31

241

Gear system  

Microsoft Academic Search

This patent describes a gear system comprising a center gear; gears each having a center axis and each meshing with the center gear; main shafts each having an axis and a conical form and each rotatably carrying one of the gears directly through a bearing having a conical hole, a clearance being provided between an outer surface of each main

K. Shinjo; M. Go

1988-01-01

242

Multipositronic Systems  

SciTech Connect

The stability and structure of systems comprising a negative ion and positrons are investigated by the stochastic variational method. It is shown that the H{sup -} and the Li{sup -} ions can bind not only one but two positrons. The binding energies of these double positronic atoms, E(H{sup -} , e{sup +}, e{sup +})=0.57 eV , and E(Li{sup -} , e{sup +}, e{sup +})=0.15 eV are somewhat smaller than those of their single positronic counterparts [E(HPs)=1.06 eV and E(LiPs)=0.32 eV ]. We have also found that two Ps{sup -} 's can form a bound system with a proton. (c) 1999 The American Physical Society.

Varga, Kalman

1999-12-27

243

Multipositronic Systems  

NASA Astrophysics Data System (ADS)

The stability and structure of systems comprising a negative ion and positrons are investigated by the stochastic variational method. It is shown that the H- and the Li- ions can bind not only one but two positrons. The binding energies of these double positronic atoms, E\\(H-,e+,e+\\) = 0.57 eV, and E\\(Li-,e+,e+\\) = 0.15 eV are somewhat smaller than those of their single positronic counterparts [ E\\(HPs\\) = 1.06 eV and E\\(LiPs\\) = 0.32 eV]. We have also found that two Ps-'s can form a bound system with a proton.

Varga, Kálmán

1999-12-01

244

Surveying System  

NASA Astrophysics Data System (ADS)

Sunrise Geodetic Surveys are setting up their equipment for a town survey. Their equipment differs from conventional surveying systems that employ transit rod and chain to measure angles and distances. They are using ISTAC Inc.'s Model 2002 positioning system, which offers fast accurate surveying with exceptional signals from orbiting satellites. The special utility of the ISTAC Model 2002 is that it can provide positioning of the highest accuracy from Navstar PPS signals because it requires no knowledge of secret codes. It operates by comparing the frequency and time phase of a Navstar signal arriving at one ISTAC receiver with the reception of the same set of signals by another receiver. Data is computer processed and translated into three dimensional position data - latitude, longitude and elevation.

1988-01-01

245

Neuroendocrine System  

Microsoft Academic Search

The physiological systems of the human body are placed under a great deal of stress during the process of exercise training.\\u000a Within elite athletes this stress can be of enormous levels because of the volume and intensity of work they perform in their\\u000a training regimes . When training stress is of an appropriate level then there is a positive adaptation

A. C. Hackney

246

Combustion systems  

SciTech Connect

This patent describes an external combustion engine such as a Stirling engine and the like, having an external heat system housing in which is defined a heater space, a hollow liner formed of a ceramic material disposed in the heater space and defining a combustion chamber. Biasing means are coupled to a first end of the liner and coupled with the housing so as to maintain the liner in the heater space while dampening transmission of vibration in the housing to the liner.

Kralick, J.

1986-03-04

247

Adrenergic System  

Microsoft Academic Search

\\u000a The adrenergic system is an essential regulator of cardiovascular, endocrine, neuronal, vegetative, and metabolic function.\\u000a The biological effects of the endogenous catecholamines epinephrine and norepinephrine are mediated by nine distinct G protein-coupled\\u000a receptor subtypes. These adrenergic receptors can be divided into three different groups, the a1-receptors (?1A, ?1B, ?1D), ?2-receptors (?2A, ?2B ?2C) ?-receptors (?1, ?2, ?3). In the absence

S. Engelhardt; L. Hein

248

Representational Systems  

Microsoft Academic Search

The concept of representation has been a key element in the scientific study of mental processes, ever since such studies\\u000a commenced. However, usage of the term has been all but too liberal—if one were to adhere to common use it remains unclear\\u000a if there are examples of physical systems which cannot be construed in terms of representation. The problem is

Tomer Fekete

2010-01-01

249

Physiological Parameters Measurement Based on Wheelchair Embedded Sensors and Advanced Signal Processing  

Microsoft Academic Search

This paper presents a multisensing system with wireless communication capabilities embedded on a smart wheelchair that can measure physiological parameters such as heart rate and respiratory rate in an unobtrusive way. Ballistocardiography (BCG) sensors and a three-axis inertial microelectromechanical system accelerometer are embedded on the seat or in the backrest of the wheelchair and the acquired data are transmitted by

Octavian A. Postolache; P. M. B. Silva Girao; Joaquim Mendes; Eduardo C. Pinheiro; Gabriela Postolache

2010-01-01

250

Expert Systems: What Is an Expert System?  

ERIC Educational Resources Information Center

Describes expert systems and discusses their use in libraries. Highlights include parts of an expert system; expert system shells; an example of how to build an expert system; a bibliography of 34 sources of information on expert systems in libraries; and a list of 10 expert system shells used in libraries. (Contains five references.) (LRW)

Duval, Beverly K.; Main, Linda

1994-01-01

251

D0 Cryo System Control System Autodialer  

Microsoft Academic Search

The DO cryogenic system is controlled by a TI565-PLC based control system. This allows the system to be unmanned when in steady state operation. System experts will need to be contacted when system parameters exceed normal operating points and reach alarm setpoints. The labwide FIRUS system provides one alarm monitor and communication link. An autodialer provides a second and more

J. Urbin

1990-01-01

252

Solar System  

NSDL National Science Digital Library

NASA is charting a bold new course into the cosmos, a journey that will take humans back to the Moon, and eventually to Mars and beyond. Exploration of the solar system and beyond will be guided by compelling questions of scientific and societal importance. NASA exploration programs will seek profound answers to questions about the origins of our solar system, whether life exists beyond Earth, and how we could live on other worlds. The NASA Vision for space exploration calls for a combination of human and robotic missions to achieve new exploration goals. Robotic missions to the Moon will be followed by an extended human expedition as early as 2015. Lunar exploration will lay the groundwork for future exploration of Mars and other destinations. A new spacecraft to support these journeys--the Crew Exploration Vehicle--will be tested before the end of this decade. Space exploration holds a special place in the human imagination. Youth are especially drawn to Mars rovers, astronauts, and telescopes. If used effectively and creatively, space can inspire children to seek careers in math, science, and engineering. Exploration and discovery are key agents of growth in society--technologically, economically, socially, internationally, and intellectually. This module is a first step in engaging today's youth in space exploration and serves as an invitation to participate in the excitement of discovery.

National Science Teachers Association (NSTA)

2005-04-01

253

Refrigeration system  

SciTech Connect

This patent describes a chamber including an expandable refrigerant system associated therewith. The system comprises reservoir containing an expandable refrigerant coolant and lead piping connecting the reservoir to conduits carrying the coolant therein. The chamber comprises top, bottom and side walls, accordingly defining an interior and an exterior to the chamber, one of the walls comprises a door affording access into the chamber, each of the walls being insulated with insulating material. At least one of the walls comprises a first layer of the insulating material extending thereover adjacent the exterior and a second layer of the insulating material extending thereover adjacent the interior. The reservoir, lead piping and conduits are disposed intermediate the first and second layers of insulating material thereby isolating them from both the interior and exterior. Heat transferring through the at least one wall is substantially absorbed by the coolant and the insulating material cooled by the coolant, before it is able to penetrate through the at least one wall, permitting a product placed in the chamber to effectively maintain or substantially maintain a selected even temperature.

Pagani, R.F.; Clarke, K.J.; Avon, E.J.

1986-11-11

254

Solar System!  

NSDL National Science Digital Library

An introduction to our solar system: the planets, our Sun and our Moon. Students begin by learning the history and engineering of space travel. They make simple rockets to acquire a basic understanding Newton's third law of motion. They explore energy transfer concepts and use renewable solar energy for cooking. They see how engineers design tools, equipment and spacecraft to go where it is too far and too dangerous for humans. They explore the Earth's water cycle, and gravity as applied to orbiting bodies. They learn the steps of the design process as they create their own planetary rovers made of edible parts. Students conduct experiments to examine soil for signs of life, and explore orbit transfers. While studying about the International Space Station (ISS), they investigate the realities of living in space. Activities explore low gravity on human muscles, eating in microgravity, and satellite tracking. Finally, students learn about the context of our solar system, the universe, as they learn about the Hubble Space Telescope, celestial navigation and spectroscopy.

Integrated Teaching And Learning Program

255

Ignition system  

SciTech Connect

This patent describes an ignition system of an internal combustion engine which consists of: a permanent magnet supported by a rotary member of the engine adapted to rotate in synchronism with a rotary shaft of the engine; a generating coil for generating an electromotive force to produce an electric current as the permanent magnet acts on the generating coil during the rotation of the rotary member; an ignition capacitor charged by the electric current generated by the generating coil; a thyristor caused to turn on by a counter electromotive force generated by the generating coil to thereby cause the ignition capacitor to begin to discharge; and an ignition coil generating a high voltage as the ignition capacitor begins to discharge, to cause a spark discharge to take place in an ignition plug of the internal combustion engine.

Kondo, T.; Ohno, S.

1986-09-16

256

Transfer system  

SciTech Connect

A transport system includes a traveling rail (1) which constitutes a transport route and a transport body (3) which is capable of traveling on the traveling rail in the longitudinal direction of the traveling rail. Flexible drive tubes (5) are arranged on the traveling rail in the longitudinal direction of the traveling rail. The transport body includes a traveling wheel (4) which is capable of rolling on the traveling rail and drive wheels (2) which are capable of rolling on the drive tubes upon receiving the rotational drive power generated by pressure of a pressure medium supplied to the drive tubes while depressing the drive tubes. The traveling rail includes a plurality of transport sections and the transport body is capable of receiving a rotational drive force from the drive tubes at every transport sections. If necessary, a transport route changeover switch which changes over the transport route can be provided between the transport sections.

Kurosawa, Kanji (Tokyo, JP); Koga, Bunichiro (Miyagi, JP); Ito, Hideki (Miyagi, JP); Kiriyama, Shigeru (Miyagi, JP); Higuchi, Shizuo (Kanagawa, JP)

2003-05-20

257

Numeration Systems  

NSDL National Science Digital Library

All About Circuits is a website that âÂÂprovides a series of online textbooks covering electricity and electronics.â Written by Tony R. Kuphaldt, the textbooks available here are wonderful resources for students, teachers, and anyone who is interested in learning more about electronics. This specific section, Numeration Systems, is the first chapter in Volume IV âÂÂDigital. A few of the topics covered in this chapter include: Numbers and symbols; Octal and hexadecimal numeration; and Conversion from decimal numeration. Diagrams and detailed descriptions of concepts are included throughout the chapter to provide users with a comprehensive lesson. Visitors to the site are also encouraged to discuss concepts and topics using the All About Circuits discussion forums (registration with the site is required to post materials).

Kuphaldt, Tony R.

2008-07-02

258

Mooring system  

SciTech Connect

This patent describes a mooring system for use on a body of water and having an anchoring structure and a flotation platform. It comprises a waterward end, a coupler comprising means for attaching the coupler with the anchoring structure to permit substantially unrestricted independent movement of the coupler in a direction substantially perpendicular to the surface of the water with substantially restricted movement of the coupler in a direction substantially parallel to the surface of the water; a link member coupled to the attachment means; means for allowing limited rotation of the link member with respect to the attachment means about a horizontally disposed axis perpendicular to the direction of movement of the coupler and means for allowing the waterward end of the flotation platform to pivot upward around the link member while preventing the flotation platform from pivoting downward substantially below the horizontal plane defined by the attachment means and the pivot means.

Hemminger, P.W.

1991-09-03

259

Skeletal System  

NSDL National Science Digital Library

Through this unit, written for an honors anatomy and physiology class, students become familiar with the human skeletal system and answer the Challenge Question: When you get home from school, your mother grabs you, and you race to the hospital. Your grandmother fell and was rushed to the emergency room. The doctor tells your family your grandmother has a fractured hip, and she is referring her to an orthopedic specialist. The orthopedic doctor decides to perform a DEXA scan. The result show her BMD is -3.3. What would be a probable diagnosis to her condition? What are some possible causes of her condition? Should her daughter and granddaughter be worried about this condition, and if so, what are measures they could take to prevent this from happening to them?

Vu Bioengineering Ret Program

260

Systems toxicology.  

PubMed

The need for a more mechanistic understanding of the ways in which chemicals modulate biological pathways is urgent if we are to identify and better assess safety issues relating to a wide range of substances developed by the pharmaceutical, chemical, agri-bio, and cosmetic industries. Omics technologies provide a valuable opportunity to refine existing methods and provide information for so-called integrated testing strategies via the creation of signatures of toxicity. By mapping these signatures to underlying pathways of toxicity, some of which have been identified by toxicologists over the last few decades, and bringing them together with pathway information determined from biochemistry and molecular biology, a "systems toxicology" approach will enable virtual experiments to be conducted that can improve the prediction of hazard and the assessment of compound toxicity. PMID:22562485

Hartung, Thomas; van Vliet, Erwin; Jaworska, Joanna; Bonilla, Leo; Skinner, Nigel; Thomas, Russell

2012-01-01

261

Battery system  

US Patent & Trademark Office Database

A battery system includes: a battery unit formed by electrically connected in series a plurality of cell groups each made up with a plurality of battery cells electrically connected in series; a plurality of sensing lines for detecting voltages of respective battery cells in the battery unit; an integrated circuit provided to each of the cell group, to which the sensing lines for detecting voltages of respective battery cells in the cell group are connected; a case having housed therein a substrate at which a plurality of integrated circuits provided for the cell groups respectively are mounted; noise protection capacitors disposed between input terminals of the plurality of sensing lines; and at least one protection element against static electricity which is connected between the input terminals and the case.

2013-08-27

262

Solar system  

SciTech Connect

An improved solar heat collecting system is described comprising: a collecting means having upper and lower end caps; means for supporting the collecting means in a position generally perpendicular to ambit solar radiation and to permit periodic adjustment thereof; the support means including a base, a first support bar pivotally secured to the base and extending parallel to the ground, and a first support member extending perpendicular from the first support bar to the lower end cap. The support means also includes a second support bar pivotally secured to the base and extending generally parallel to the first support bar, a support leg having a lower portion that extends perpendicularly from the second support bar, an intermediate leg portion slidingly mounted on the lower leg portion and an upper leg portion pivotally secured to the intermediate leg portion, and a second support member extending perpendicularly from the upper leg portion to the upper end cap; lens means disposed above the collecting means for concentrating solar radiation on the collecting means; a pair of reflector means mounted below and on opposite sides of the radiation shadow of the lens means for concentrating solar radiation on the collecting means; mounting means for mounting the lens means and the reflector means. The mounting means includes first and second bracket means rotatively mounted respectively to the first and second support members. A pair of radially extending U-shaped reflector mounts have opposite ends secured to respective bracket means, and a pair of radially extending lens supports secured to respective bracket means; and means for rotating the mounting means and associated lens mean and reflector means to track the source of solar radiation whereby an improved, highly efficient solar heat collecting system is provided.

Gregory, S.T.

1987-02-24

263

Technology reviews: Glazing systems.  

National Technical Information Service (NTIS)

We present a representative review of existing, emerging, and future technology options in each of five hardware and systems areas in envelope and lighting technologies: lighting systems, glazing systems, shading systems, daylighting optical systems, and ...

J. Schuman F. Rubinstein K. Papamichael L. Beltran E. S. Lee

1992-01-01

264

Prosthetic Knee Systems  

MedlinePLUS

... of fluid control systems — pneumatic (using air) and hydraulic (using fluid). Pneumatic control. These systems: compress air ... control than friction systems are less effective than hydraulic systems. Hydraulic control. These systems: use liquid (usually ...

265

Systems concepts for training systems development  

Microsoft Academic Search

Reviews literature showing the effects of fragmented training development and presents systems theory and training systems concepts and definitions. The author also discusses system-oriented research issues in the areas of training needs and goals analysis, training device design and use, and training system evaluation. It is shown that a systems perspective will facilitate communication between the diverse individuals engaged in

Robert T. Hays

1992-01-01

266

Acquisitions Systems: Sydney Micro Library System.  

ERIC Educational Resources Information Center

|The Sydney Micro Library System is a microcomputer-based integrated library system with cataloging, inquiry, and system management modules that form the base system for running the optional acquisitions, circulation, serials, and MARC record modules. Designed for small special libraries, the system has parallel minicomputer and microcomputer…

Desmarais, Norman

1986-01-01

267

A planning support system for system of systems engineering  

Microsoft Academic Search

This paper describes a planning system for SOSE (system of systems engineering). Based on the analysis of the characteristics of the planning for SOSE, the architecture framework of the planning system is introduced, which not only supports the process design and organization design, but also monitor of SOSE process. A plan representation is proposed for planning SOSE, which emphasizes on

Yong Wang; Zhong Liu; Wei-Ming Zhang; Jin-Cai Huang; Bao-Xin Xiu

2007-01-01

268

Ignition system  

SciTech Connect

An ignition system for a spark ignited internal combustion engine is described comprising, a source of direct voltage having positive and negative terminals, an ignition coil having a primary winding and a secondary winding, an N-channel semiconductor device having a gate, a drain and a source, means connecting the positive terminal of the direct voltage source to the drain means connecting the primary winding between the source of the N-channel semiconductor device and the negative terminal of the direct voltage source, a semiconductor switch means connected between the gate and source of the N-channel semiconductor device. The semiconductor switch means when conductive connecting the gate and source of the N-channel semiconductor device, means for biasing the N-channel semiconductor device on and off. The primary winding develops a flyback voltage that is negative at its end that is connected to the source of the N-channel semiconductor device when the N-channel semiconductor device is biased off, and means for causing the semiconductor switch means to be biased conductive in response to the development of the flyback voltage to thereby maintain the N-channel semiconductor device off.

Haines, D.L.; Hopper, D.H.

1988-04-19

269

Site systems engineering: Systems engineering management plan.  

National Technical Information Service (NTIS)

The Site Systems Engineering Management Plan (SEMP) is the Westinghouse Hanford Company (WHC) implementation document for the Hanford Site Systems Engineering Policy, (RLPD 430.1) and Systems Engineering Criteria Document and Implementing Directive, (RLID...

M. L. Grygiel

1996-01-01

270

Design and application of electromechanical actuators for deep space missions  

NASA Astrophysics Data System (ADS)

The annual report Design and Application of Electromechanical Actuators for Deep Space Missions is presented. The reporting period is 16 Aug. 1992 to 15 Aug. 1993. However, the primary focus will be work performed since submission of our semi-annual progress report in Feb. 1993. Substantial progress was made. We currently feel confident in providing guidelines for motor and control strategy selection in electromechanical actuators to be used in thrust vector control (TVC) applications. A small portion was presented in the semi-annual report. At this point, we have implemented highly detailed simulations of various motor/drive systems. The primary motor candidates were the brushless dc machine, permanent magnet synchronous machine, and the induction machine. The primary control implementations were pulse width modulation and hysteresis current control. Each of the two control strategies were applied to each of the three motor choices. With either pulse width modulation or hysteresis current control, the induction machine was always vector controlled. A standard test position command sequence for system performance evaluation is defined. Currently, we are gathering all of the necessary data for formal presentation of the results. Briefly stated for TVC application, we feel that the brushless dc machine operating under PWM current control is the best option. Substantial details on the topic, with supporting simulation results, will be provided later, in the form of a technical paper prepared for submission and also in the next progress report with more detail than allowed for paper publication.

Haskew, Tim A.; Wander, John

1993-09-01

271

Design of template to fabricate magnetic torquer coils for nano and picosatellite missions  

Microsoft Academic Search

Purpose – Recent advances in nano and picosatellite missions and future such missions require three axis attitude control system hardware for attitude control purposes. A simple, cost effective, yet an efficient devise that is used for active attitude control is magnetic torquer coil. The purpose of this paper is to describe the design and fabrication of a template to manufacture

Sanjay Jayaram

2010-01-01

272

A Physics Road Rally  

ERIC Educational Resources Information Center

|Our school recently acquired Vernier's Wireless Dynamics Sensor System (WDSS). The WDSS consists of a three-axis accelerometer, altimeter, and force sensor that has the ability to remotely collect data for later transfer to a computer. While our primary purpose for acquiring the WDSS was to enhance our amusement park physics experiments, we…

Ilyes, Mark A.; Ortman-Link, Whitney

2009-01-01

273

A Physics Road Rally  

ERIC Educational Resources Information Center

Our school recently acquired Vernier's Wireless Dynamics Sensor System (WDSS). The WDSS consists of a three-axis accelerometer, altimeter, and force sensor that has the ability to remotely collect data for later transfer to a computer. While our primary purpose for acquiring the WDSS was to enhance our amusement park physics experiments, we…

Ilyes, Mark A.; Ortman-Link, Whitney

2009-01-01

274

Real-Time Recursive Filter for the Attitude Determination of the Spacelab Instrument Pointing Subsystem.  

National Technical Information Service (NTIS)

A real-time estimation filter which reduces sensitivity to system variations and reduces the amount of preflight computation is developed for the instrument pointing subsystem (IPS). The IPS is a three-axis stabilized platform developed to point various a...

M. E. West

1992-01-01

275

A double gimballed magnetic bearing momentum wheel for high pointing accuracy and vibration sensitive space applications  

Microsoft Academic Search

A fully controlled magnetic bearing momentum wheel is well suited as gyroscopic actuator in the attitude control system of spacecraft. It offers the following advantages: an active tilting of the momentum vector with respect to the spacecraft ('vernier gimballing') with the following features: very little power required; three axis attitude control of the spacecraft in a fine pointing range with

U. J. Bichler

1991-01-01

276

FRACTIONAL REGULATORS FOR SPACECRAFT ATTITUDE STABILIZATION  

Microsoft Academic Search

In order to enhance the performances and satisfy pointing requirements of communication spacecraft or intelligence gathering purposes, Fractional Order Control (FOC) methods were applied to a three-axis reaction wheels spacecraft attitude control system. In this paper, Low Earth Orbit satellite attitude stabilisation with fractional control laws methods is presented. First, the theory relating to such a law of control have

A. Kailil; N. Mrani; M. Abid; S. Choukri; M. Mliha Touati; N. Elalami

2004-01-01

277

Fuzzy Neural Control of Satellite Attitude by TD Based Reinforcement Learning  

Microsoft Academic Search

With recent development of the space science and technology, higher requirements such as accuracy, robustness and disturbance rejection ability in satellite attitude control system have led to the more promising intelligent control methods. In this paper, a fuzzy neural control approach applied to the three-axis stabilized satellite is presented. In order to solve the problems of online learning and tuning

Xiao-ting Cui; Xiang-dong Liu

2006-01-01

278

Microprocessor Control of Low Speed VSTOL Flight.  

National Technical Information Service (NTIS)

The objective of this project has been to design an improved three-axis stability augmentation system (SAS) for the AV-8B Advanced Harrier VSTOL aircraft using microprocessor-based digital control. The research focuses on improving the handling qualities ...

R. V. Walters

1979-01-01

279

System design description cone penetrometer system  

SciTech Connect

The system design description documents in detail the design of the cone penetrometer system. The systems includes the cone penetrometer physical package, raman spectroscopy package and moisture sensor package. Information pertinent to the system design, development, fabrication and testing is provided.

Seda, R.Y., Westinghouse Hanford

1996-08-12

280

Site systems engineering: Systems engineering management plan  

Microsoft Academic Search

The Site Systems Engineering Management Plan (SEMP) is the Westinghouse Hanford Company (WHC) implementation document for the Hanford Site Systems Engineering Policy, (RLPD 430.1) and Systems Engineering Criteria Document and Implementing Directive, (RLID 430.1). These documents define the US Department of Energy (DOE), Richland Operations Office (RL) processes and products to be used at Hanford to implement the systems engineering

Grygiel

1996-01-01

281

D0 Cryo System Control System Autodialer  

SciTech Connect

The DO cryogenic system is controlled by a TI565-PLC based control system. This allows the system to be unmanned when in steady state operation. System experts will need to be contacted when system parameters exceed normal operating points and reach alarm setpoints. The labwide FIRUS system provides one alarm monitor and communication link. An autodialer provides a second and more flexible alarm monitor and communication link. The autodialer monitors contact points in the control system and after receiving indication of an alarm accesses a list of experts which it calls until it receives an acknowledgement. There are several manufacturers and distributors of autodialer systems. This EN explains the search process the DO cryo group used to fmd an autodialer system that fit the cryo system's needs and includes information and specs for the unit we chose.

Urbin, J.; /Fermilab

1990-04-17

282

Photovoltaic System Research Status.  

National Technical Information Service (NTIS)

After a decade of photovoltaic system research, most system related issues have been successfully resolved. Current system research activities are now oriented toward maintaining and updating the comprehensive database on system performance established by...

H. N. Post G. J. Jones M. G. Thomas

1989-01-01

283

A Stimuli Presentation System.  

National Technical Information Service (NTIS)

Laboratory and research field trip requirements have revealed the need for a programmable audio switching system. This system, the stimuli presentation system (SPS), is designed with general versatility in mind. Although the system was conceived for use i...

W. D. Harrington H. Hollien H. Rothman

1969-01-01

284

Integrated library systems.  

PubMed Central

The development of integrated library systems is discussed. The four major discussion points are (1) initial efforts; (2) network resources; (3) minicomputer-based systems; and (4) beyond library automation. Four existing systems are cited as examples of current systems.

Goldstein, C M

1983-01-01

285

Continuous Informations Systems.  

National Technical Information Service (NTIS)

The motion of an algebraic information system is generalized to that of a continuous information system. Just as algebraic information systems are concrete representations of bounded complete algebraic dcpo's (Scott domains), continuous information system...

R. Hoofman

1990-01-01

286

Mechanical Systems: A Compilation.  

National Technical Information Service (NTIS)

A compilation of several mechanized systems is presented. The articles are contained in three sections: robotics, industrial mechanical systems, including several on linear and rotary systems and lastly mechanical control systems, such as brakes and clutc...

1975-01-01

287

TPAP Operating System Executive.  

National Technical Information Service (NTIS)

This report describes a special purpose, virtual operating system designed to enhance the flexibility and capability of the Transaction Processing System within the Honeywell Series 60/6000/600 Information Systems. The special purpose operating system is ...

R. Ewing

1975-01-01

288

Stanchion System Upgrade  

NSF Publications Database

... utility systems on poles will be relocated to the above ground stanchion system. As part of this ... current utility system will remain the same at McMurdo Station. The current system presents numerous ...

289

The Solar System  

NSDL National Science Digital Library

What are the parts of our solar system? Let's learn about the parts of our Solar System! First, use the Solar System Chart Now read the Introduction to the Solar System and begin filling out the Solar System Chart by listing one fact for each planet. Now watch the Video 1 on the Solar System and fill out one characteristic about each planet in our Solar System. Now read the Facts about the Solar System and find ...

Kathrynbyers

2012-04-05

290

Experimental Investigation of Axial and Beam-Riding Propulsive Physics with TEA CO2 laser  

NASA Astrophysics Data System (ADS)

A twin Lumonics K922M pulsed TEA CO2 laser system (pulse duration of approximately 100 ns FWHM spike, with optional 1 ?s tail, depending upon laser gas mix) was employed to experimentally measure both axial thrust and beam-riding behavior of Type No.200 lightcraft engines, using a ballistic pendulum and Angular Impulse Measurement Device (AIMD, respectively. Beam-riding forces and moments were examined along with engine thrust-vectoring behavior, as a function of: a) laser beam lateral offset from the vehicle axis of symmetry; b) laser pulse energy (~12 to 40 joules) c) pulse duration (100 ns, and 1 ?s) and d) engine size (97.7 mm to 161.2 mm). Maximum lateral momentum coupling coefficients (CM) of 75 N-s/MJ were achieved with the K922M laser whereas previous PLVTS laser (420 J, 18 ?s duration) results reached only 15 N-s/MJ-an improvement of 5x. Maximum axial CM performance with the K922M reached 225 N-s/MJ, or about ~3x larger than the lateral CM values. These axial CM results are sharply higher than the 120 N/MW previously reported for long pulse (e.g., 10-18 ?s) CO2 electric discharge lasers.

Kenoyer, D. A.; Salvador, I.; Myrabo, L. N.; Notaro, S. N.; Bragulla, P. W.

2010-10-01

291

IHPRPT Phase I Solid Boost Demonstrator: A Success Story  

NASA Astrophysics Data System (ADS)

The integrated High-Payoff Rocket Propulsion Technology or IHPRPT program seeks to double the launch capability of the United States by the year 2010. The program is organized into three phases, with a technology demonstrator at the end of each phase. The IHPRPT Phase I Solid Boost Demonstrator Program is presented. Materials and processing technologies developed under the IHPRPT program and on other contracted technology and privately funded programs were combined into one full-scale booster demonstrator culminating six years of new technology work. New materials and processes were used in all components of the demonstration motor to achieve the cost and performance goals identified for the Phase I Boost & Orbit Transfer Propulsion mission area in the IHPRPT program. New materials utilized in the motor included low cost high performance carbon fibers in the composite case energetic ingredients in the propellant. net molded structural parts in the nozzle. and an all-new electromechanical Thrust Vector Actuation (TVA) system. The demonstrator was successfully static tested on 16 November 2000 The static test has been heralded as a success by government and industry observers alike.

Glaittli, Steven R.

2001-06-01

292

Laser Plasma Microthruster Performance Evaluation  

NASA Astrophysics Data System (ADS)

The micro laser plasma thruster (?LPT) is a sub-kilogram thruster that is capable of meeting the Air Force requirements for the Attitude Control System on a 100-kg class small satellite. The ?LPT uses one or more 4W diode lasers to ablate a solid fuel, producing a jet of hot gas or plasma which creates thrust with a high thrust/power ratio. A pre-prototype continuous thrust experiment has been constructed and tested. The continuous thrust experiment uses a 505 mm long continuous loop fuel tape, which consists of a black laser-absorbing fuel material on a transparent plastic substrate. When the laser is operated continuously, the exhaust plume and thrust vector are steered in the direction of the tape motion. Thrust steering can be avoided by pulsing the laser. A torsion pendulum thrust stand has been constructed and calibrated. Many fuel materials and substrates have been tested. Best performance from a non-energetic fuel material was obtained with black polyvinyl chloride (PVC), which produced an average of 70 ?N thrust and coupling coefficient (Cm) of 190 ?N/W. A proprietary energetic material was also tested, in which the laser initiates a non-propagating detonation. This material produced 500 ?N of thrust.

Luke, James R.; Phipps, Claude R.

2003-05-01

293

Extensible Virtual Environment Systems Using System of Systems Engineering Approach  

Microsoft Academic Search

The development of Virtual Environment (VE) systems is a challenging endeavor with a complex problem domain. The experience in the past decade has helped contribute significantly to various measures of software quality of the resulting VE systems. However, the resulting solutions remain monolithic in nature without addressing successfully the issue of system interoperability and software aging. This paper argues that

Manuel Oliveira; Joao Pereira

2007-01-01

294

On Long Lifespan systems  

Microsoft Academic Search

Complex systems are not only characterized by their magnitudes, but also their lifespans. This paper presents a theory of Long-Lifespan systems (LLS's) and its applications in explaining the properties of complex systems from both the function and time dimensions. The mathematical models of LLS's such as those of the abstract systems, system magnitudes, and system lifespan, are established. Then, properties

Yingxu Wang

2008-01-01

295

Controllability of molecular systems  

Microsoft Academic Search

In this paper we analyze the controllability of quantum systems arising in molecular dynamics. We model these systems as systems with finite numbers of levels, and examine their controllability. To do this we pass to their unitary generators and use results on the controllability of invariant systems on Lie groups. Examples of molecular systems, modeled as finite-dimensional control systems, are

Viswanath Ramakrishna; Murti V. Salapaka; Mohammed Dahleh; Herschel Rabitz; Anthony Peirce

1995-01-01

296

System of systems modeling and analysis.  

SciTech Connect

This report documents the results of an LDRD program entitled 'System of Systems Modeling and Analysis' that was conducted during FY 2003 and FY 2004. Systems that themselves consist of multiple systems (referred to here as System of Systems or SoS) introduce a level of complexity to systems performance analysis and optimization that is not readily addressable by existing capabilities. The objective of the 'System of Systems Modeling and Analysis' project was to develop an integrated modeling and simulation environment that addresses the complex SoS modeling and analysis needs. The approach to meeting this objective involved two key efforts. First, a static analysis approach, called state modeling, has been developed that is useful for analyzing the average performance of systems over defined use conditions. The state modeling capability supports analysis and optimization of multiple systems and multiple performance measures or measures of effectiveness. The second effort involves time simulation which represents every system in the simulation using an encapsulated state model (State Model Object or SMO). The time simulation can analyze any number of systems including cross-platform dependencies and a detailed treatment of the logistics required to support the systems in a defined mission.

Campbell, James E.; Anderson, Dennis James; Longsine, Dennis E. (Intera, Inc., Austin, TX); Shirah, Donald N.

2005-01-01

297

Quantitative solar system science with AO systems  

NASA Astrophysics Data System (ADS)

Adaptive Optics systems, today available on 8-10m class telescopes are playing a significant role in the study of our solar system bodies. We describe three main science cases i) small solar system bodies ii) satellites of giant planets iii) giant planets atmospheres. We describe recent results acquired with these systems in these fields. We discuss the limitation and potential of AO systems for these studies, and address the problem of observability specific to moving targets. The potential for planetary science of future and improved AO systems is described.

Marchis, Franck; Berthier, Jerome; Wong, Michael H.

2012-07-01

298

Social Services Information System: System Description Manual.  

National Technical Information Service (NTIS)

The design and implementation philosophy of the Social Services Information System (SSIS) of the Colorado Department of Social Services are described, and technical background and systems documentation are provided in a manual intended for technical perso...

1975-01-01

299

An Operating System Independent WORM Archival System  

Microsoft Academic Search

SUMMARY We describe the organization of a general purpose data archival system for Write-Once, Read-Many (WORM) optical disks. The system has been designed for large-scale and long-term data storage and retrieval. The archival system is independent of the operating system, flat, self-consistent, does not use any write cache on magnetic disk, and allows the exploitation of auxiliary information on magnetic

Guido Russo; Stefano Russo

1995-01-01

300

LCLS XTOD Attenuator System System Concept Report  

SciTech Connect

The attenuator system for the Linac Coherent Light Source (LCLS) X-ray Transport, Optics and Diagnostics (XTOD) system has been configured and analyzed by the Lawrence Livermore National Laboratory's New Technologies Engineering Division (NTED) as requested by the SLAC/LCLS program. The system layout, performance analyses and selection of the vacuum components are presented in this System Conceptual Review (SCR) report. Also included are the plans for prototype, procurement, mechanical integration, and the cost estimates.

Kishiyama, K; Roeben, M; Trent, J; Ryutov, D; Shen, S

2006-04-12

301

Randomization for Testing Systems of Systems  

Microsoft Academic Search

This paper applies randomization theory to the problem of selecting software test cases for software systems and applications in order to overcome the hurdle of high cost in testing componentized systems of systems (SoS). We have used a corner point semantics, which can approximate a proof of correctness - termed a pseudo-proof of correctness. Test cases for each component are

Qianhui Althea Liang; Stuart Harvey Rubin

2009-01-01

302

A systems analysis of systems integration  

Microsoft Academic Search

Most if not all complex issues stated as problems intended to result in new systems may be analyzed using systems decomposition and then constructed by synthesis. Systems decomposition starts with a complex problem that may or may not be obviously solvable and deconstructs that problem into smaller more tractable problems that can be solved. Construction by synthesis treats the smaller

Robert Schaefer

2008-01-01

303

Systems Engineering Cost Estimation for Space Systems  

Microsoft Academic Search

The applicability of COSYSMO, a systems engineering cost model, is explored in the context of space systems through the analysis of two main assumptions. First, the WBS elements of the model are mapped to a prototypical WBS for space systems. Second, the life cycle phases assumed in the model are mapped to the phases outlined in the latest National Security

Ricardo Valerdi; Marilee J. Wheaton; Jared Fortune

2007-01-01

304

CPS (Collective Protective System) Alarm System.  

National Technical Information Service (NTIS)

An improved collective protection system (CPS) alarm is generally comprised of an electronic circuit board terminal box that is readily connectable to any selected point of a ship power bus system. The system is provided with a plurality of pressure trans...

B. A. Repp A. M. Wurm A. J. Simonoff S. R. Courtney

1988-01-01

305

Immune System Based Intrusion Detection System  

Microsoft Academic Search

The threats and intrusions in IT systems can basically be compared to human diseases with the difference that the human body has an effective way to deal with them, what still need to be designed for IT systems. The human immune system (HIS) can detect and defend against yet unseen intruders, is distributed, adaptive and multilayered to name only a

Christoph Ehret; Ulrich Ultes-nitsche

2008-01-01

306

Intelligence systems: a sociotechnical systems perspective  

Microsoft Academic Search

To effectively compete a firm needs to take advantage of their intellectual capital. However, intellectual capital alone is not sufficient to capitalize on the intellectual assets of the firm. An intelligence system is also necessary. We propose an intelligence system, consisting of four evolving components: a corporate data base of transaction processing and management information systems, a decision-making environment of

James A. Sena

1999-01-01

307

Enhancing Ubiquitous Systems through System Call Mining  

Microsoft Academic Search

Collecting, monitoring, and analyzing data automatically by well instrumented systems is frequently motivated by human decision-making. However, the same need occurs when system software decisions are to be justified. Compiler optimization or storage management requires several decisions which result in more or less resource consumption, be it energy, memory, or runtime. A magnitude of system data can be collected in

Katharina Morik; Felix Jungermann; Nico Piatkowski; Michael Engel

2010-01-01

308

Clinical information systems.  

PubMed

Clinical information systems are the computer and information systems used by health care personnel to facilitate patient care. These systems have evolved from financial systems to true patient care systems with variable levels of functionality. Early systems provided laboratory and radiology results, and modern systems now provide copies of the radiology images and decision support for therapeutic orders. The rapidly changing technological infrastructure has created barriers to implementation of the electronic medical record, while coding schemes continue to be refined to enable data access and aggregate data analysis. Further refinement of clinical information systems is required before the potential value of these systems is realized in the clinical management of patients. PMID:10688384

Hardin, W D

2000-02-01

309

Expert Systems: An Overview.  

ERIC Educational Resources Information Center

Discusses: (1) the architecture of expert systems; (2) features that distinguish expert systems from conventional programs; (3) conditions necessary to select a particular application for the development of successful expert systems; (4) issues to be resolved when building expert systems; and (5) limitations. Examples of selected expert systems

Adiga, Sadashiv

1984-01-01

310

Interactive Video Authoring Systems.  

ERIC Educational Resources Information Center

|Five articles describe the following microcomputer-based interactive video authoring aids: (1) IBM's Learning System/1; (2) Video Nova Authoring System; (3) IMSATT Corporation's expert-based authoring system; (4) the System for Authoring Microtraining (SAM); and (5) Omnicom's Content Expert Interviewer and Interactive Design and Authoring System.…

Taylor, Timothy D.; And Others

1987-01-01

311

Power system commonality study  

Microsoft Academic Search

A limited top level study was completed to determine the commonality of power system\\/subsystem concepts within potential lunar and Mars surface power system architectures. A list of power system concepts with high commonality was developed which can be used to synthesize power system architectures which minimize development cost. Examples of potential high commonality power system architectures are given in this

Franklin D. Littman

1992-01-01

312

Heliospheric coordinate systems  

Microsoft Academic Search

This article gives an overview and reference to the most common coordinate systems currently used in space science. While coordinate systems used in near-Earth space physics have been described in previous work we extend that description to systems used for physical observations of the Sun and the planets and to systems based on spacecraft location. For all systems, we define

M. Fränz; D. Harper

2002-01-01

313

Anticipatory systems in physics  

Microsoft Academic Search

Purpose – The study of anticipatory systems assumes the existence of two distinct types of systems in nature. Some systems anticipate the future and such anticipation forms part of the system itself, while other systems, however, do not anticipate and solely rely on past states. This article aims to argue that this distinction is inadequate given the current understanding of

J. Ferret

2010-01-01

314

Organization in Biological Systems  

Microsoft Academic Search

Biological systems are typically hierarchically organized, open, nonlinear systems, and inherit all of the characteristics of such systems that are found in the purely physical and chemical domains, to which all biological systems belong. In addition, biological systems exhibit functional properties, and they contain information in a form that is used internally to make required functional distinctions. The existence of

John Collier

315

System Specification in Rosetta  

Microsoft Academic Search

System level specification and analysis has become a critical issue in designing today's ever increasingly complex systems. System level design is distinguished from other design activities by its heterogeneous nature. Specifically, systems level designers must integrate information from many different design domains in a single design decision making activity. Rosetta is a systems level specification language that addresses problems specific

Perry Alexander; Roshan Kamath; David Barton

2000-01-01

316

The LSST: A System of Systems  

NASA Astrophysics Data System (ADS)

The Large Synoptic Survey Telescope (LSST) is a complete observing system that acquires and archives images, processes and analyzes them, and publishes reduced images and catalogs of sources and objects. The LSST will operate over a ten year period producing a survey of 20,000 square degrees over the entire [Southern] sky in 6 filters (ugrizy) with each field having been visited several hundred times enabling a wide spectrum of science from fast transients to exploration of dark matter and dark energy. The LSST itself is a complex system of systems consisting of the 8.4m 3-mirror telescope, a 3.2 billion pixel camera, and a peta-scale data management system. The LSST project uses a Model Based Systems Engineering (MBSE) methodology to ensure an integrated approach to system design and rigorous definition of system interfaces and specifications. The MBSE methodology is applied through modeling of the LSST's systems with the System Modeling Language (SysML). The SysML modeling recursively establishes the threefold relationship between requirements, logical & physical functional decomposition and definition, and system and component behavior at successively deeper level of abstraction and detail. The LSST modeling includes the analysis and documenting the flow of command and control information and data between the suite of systems in the LSST observatory that are needed to carry out the activities of the survey. The MBSE approach is applied throughout all stages of the project from design, to validation and verification, though to commissioning.

Claver, Chuck F.; Debois-Felsmann, G. P.; Delgado, F.; Hascall, P.; Marshall, S.; Nordby, M.; Schumacher, G.; Sebag, J.; LSST Collaboration

2011-01-01

317

What Are Expert Systems?  

ERIC Educational Resources Information Center

Intended for potential business users, this paper describes the main characteristics of expert systems; discusses practical use considerations; presents a taxonomy of the systems; and reviews several expert system development projects in business and industry. (MBR)

d'Agapeyeff, A.

1986-01-01

318

Spaceplane system studies  

Microsoft Academic Search

Basic system concepts of Japanese spaceplane research and development are presented. The single stage to orbit system of the spaceplane is illustrated. The hypersonic airbreathing propulsion system is addressed.

Masataka Maita

1991-01-01

319

Orthopedics Clinic Assistant System.  

National Technical Information Service (NTIS)

This research proposed a system, which integrated the complete patient information, including the medical images, for assisting orthopedics clinic diagnosis. The system concurrently operated with legacy systems and conformed itself to correspond with the ...

S. Tang Y. Huang M. Hsiao T. Lee S. Young

2001-01-01

320

Lesson 44: Nonlinear Systems  

NSDL National Science Digital Library

Using a cost/revenue application problem, the lesson begins with systems involving quadratic equations. Systems with conics are introduced next along with the elimination method for solving these systems.

2011-01-01

321

Maglev systems development status  

Microsoft Academic Search

The current status and future potential of Maglev systems is reviewed. Modes of noncontact suspension and propulsion are described, and prototype systems and design concepts are indicated. A number of existing systems are described in more detail

A. R. Eastham; W. F. Hayes

1988-01-01

322

Neutron Radiographic Viewing System.  

National Technical Information Service (NTIS)

The design, development and application of a neutron radiographic viewing system for use in nondestructive testing applications is considered. The system consists of a SEC vidicon camera, neutron image intensifier system, disc recorder, and TV readout. Ne...

1972-01-01

323

Assistive Listening Systems.  

National Technical Information Service (NTIS)

The pamphlet describes commercially available devices and systems for making public address and other types of communication systems more accessible to persons with hearing impairments. It describes types of systems and their installation.

1989-01-01

324

Flash Evaporator Systems Test.  

National Technical Information Service (NTIS)

A flash evaporator heat rejection system representative of that proposed for the space shuttle orbiter underwent extensive system testing at the NASA Johnson Space Center (JSC) to determine its operational suitability and to establish system performance/o...

J. B. Dietz

1976-01-01

325

Street Address Conversion System.  

National Technical Information Service (NTIS)

The report documents the genesis of the Urban Data Center 'Street Address Conversion System,' the prototype street address geocoding system operational in the Seattle, Washington, area. Three basic system concepts are defined: the 'grid block,' the 'stree...

R. B. Dial

1964-01-01

326

Hybrid Systems Diagnosis.  

National Technical Information Service (NTIS)

This paper reports on an on-going Project to investigate techniques to diagnose complex dynamical systems that are modeled as hybrid systems. In particular, we examine continuous systems with embedded supervisory controllers that experience abrupt, partia...

S. McIlraith G. Biswas D. Clancy V. Gupta

2005-01-01

327

Ammonia Production Systems Integration.  

National Technical Information Service (NTIS)

Conceptual designs of 11 mobile ammonia fuel production systems were prepared. These systems represent various combinations of total electric power to the system, mobility class, electrical power frequency, and cooling medium. This report presents a descr...

B. N. Thomson G. E. Hook N. T. Mills R. A. Coval R. M. Reinstrom

1966-01-01

328

Autonomic Nervous System Disorders  

MedlinePLUS

Your autonomic nervous system is the part of your nervous system that controls involuntary actions, such as the beating of your heart ... breathing and swallowing Erectile dysfunction in men Autonomic nervous system disorders can occur alone or as the result ...

329

Hermes Propulsion System.  

National Technical Information Service (NTIS)

The initial baseline concept of the storable bipropellant propulsion system of the Hermes spaceplane is discussed. The general architecture of the propulsion system is shown. The design features of the engines of the main propulsion system and of the thru...

H. Immich H. Hopmann T. Caussin

1987-01-01

330

Tropix Power System Architecture.  

National Technical Information Service (NTIS)

This document contains results obtained in the process of performing a power system definition study of the TROPIX power management and distribution system (PMAD). Requirements derived from the PMADs interaction with other spacecraft systems are discussed...

D. B. Manner J. M. Hickman

1995-01-01

331

Portable Graphics System.  

National Technical Information Service (NTIS)

LASL implemented a graphics system designed to support all graphics devices in all operating environments at LASL. This system, Common Graphics System (CGS), supports level one of the graphics standard proposed by the ACM/SIGGRAPH Graphics Standards Plann...

R. G. Kellner T. N. Reed A. V. Solem

1978-01-01

332

Fireproof Brake Hydraulic System.  

National Technical Information Service (NTIS)

The feasibility of a fireproof two-fluid brake hydraulic system which utilizes nonflammable chlorotrifluoroethylene (CTFE) fluid in a dead ended brake hydraulic system mechanically isolated from the primary MIL-H-5606 hydraulic system was studied. Experim...

S. M. Warren J. R. Kilner

1981-01-01

333

Systems interface biology  

PubMed Central

The field of systems biology has attracted the attention of biologists, engineers, mathematicians, physicists, chemists and others in an endeavour to create systems-level understanding of complex biological networks. In particular, systems engineering methods are finding unique opportunities in characterizing the rich behaviour exhibited by biological systems. In the same manner, these new classes of biological problems are motivating novel developments in theoretical systems approaches. Hence, the interface between systems and biology is of mutual benefit to both disciplines.

Doyle, Francis J; Stelling, Jorg

2006-01-01

334

The LSST: A System of Systems  

NASA Astrophysics Data System (ADS)

The LSST is a complete observing system that acquires and archives images, processes and analyzes them, and publishes reduced images and catalogs of sources and objects. The LSST will operate over a ten year period producing a survey of 20,000 square degrees over the entire southern sky in 6 filters (ugrizy) with each field having been visited several hundred times enabling a wide spectrum of science from fast transients to exploration of dark matter and dark energy. The LSST itself is a complex system of systems consisting of the 8.4m three mirror telescope, a 3.2 billion pixel camera, and a peta-scale data management system. The LSST project uses a Model Based Systems Engineering (MBSE) methodology to ensure an integrated approach to system design and rigorous definition of system interfaces and specifications. The MBSE methodology is applied through modeling of the LSST's systems with the System Modeling Language (SysML). The SysML modeling recursively establishes the threefold relationship between requirements, logical & physical functional decomposition and definition, and system and component behavior at successively deeper levels of abstraction and detail. The MBSE approach is applied throughout all stages of the project from design, to validation and verification, though to commissioning.

Claver, Chuck F.; Dubois-Felsmann, G. P.; Delgado, F.; Hascall, P.; Horn, D.; Marshall, S.; Nordby, M.; Schalk, T. L.; Schumacher, G.; Sebag, J.; LSST Project Team

2010-01-01

335

Umbra's system representation.  

SciTech Connect

This document describes the Umbra System representation. Umbra System representation, initially developed in the spring of 2003, is implemented in Incr/Tcl using concepts borrowed from Carnegie Mellon University's Architecture Description Language (ADL) called Acme. In the spring of 2004 through January 2005, System was converted to Umbra 4, extended slightly, and adopted as the underlying software system for a variety of Umbra applications that support Complex Systems Engineering (CSE) and Complex Adaptive Systems Engineering (CASE). System is now a standard part Of Umbra 4. While Umbra 4 also includes an XML parser for System, the XML parser and Schema are not described in this document.

McDonald, Michael James

2005-07-01

336

Spectra Optia Apheresis System  

Center for Biologics Evaluation and Research (CBER)

... Spectra Optia Apheresis System. Applicant: Terumo BCT, Inc. 510(k) number: BK120076. Product: Spectra Optia® Apheresis System. ... More results from www.fda.gov/biologicsbloodvaccines/bloodbloodproducts/approvedproducts

337

Control system design method  

DOEpatents

A control system design method and concomitant control system comprising representing a physical apparatus to be controlled as a Hamiltonian system, determining elements of the Hamiltonian system representation which are power generators, power dissipators, and power storage devices, analyzing stability and performance of the Hamiltonian system based on the results of the determining step and determining necessary and sufficient conditions for stability of the Hamiltonian system, creating a stable control system based on the results of the analyzing step, and employing the resulting control system to control the physical apparatus.

Wilson, David G. (Tijeras, NM); Robinett, III, Rush D. (Tijeras, NM)

2012-02-21

338

Epilogue: Systems Approaches and Systems Practice  

NASA Astrophysics Data System (ADS)

Each of the five systems approaches discussed in this volume: system dynamics (SD), the viable systems model (VSM), strategic options development and analysis (SODA), soft systems methodology (SSM) and critical systems heuristics (CSH) has a pedigree. Not in the sense of the sometimes absurd spectacle of animals paraded at dog shows. Rather, their pedigree derives from their systems foundations, their capacity to evolve and their flexibility in use. None of the five approaches has developed out of use in restricted and controlled contexts of either low or high levels of complicatedness. Neither has any one of them evolved as a consequence of being applied only to situations with either presumed stakeholder agreement on purpose, or courteous disagreement amongst stakeholders, or stakeholder coercion. The compilation is not a celebration of abstract ‘methodologies', but of theoretically robust approaches that have a genuine pedigree in practice.

Reynolds, Martin; Holwell, Sue

339

INSENS sensor system  

SciTech Connect

This paper describes an unattended ground sensor system that has been developed for the immigration and Naturalization Service (INS). The system, known as INSENS, was developed at the Lawrence Livermore National Laboratory for use by the United States Border Patrol. This system assists in the detection of illegal entry of aliens and contraband (illegal drugs, etc.) into the United States along its land borders. Key to the system is its flexible modular design which allows future software and hardware enhancements to the system without altering the fundamental architecture of the system. Elements of the system include a sensor system capable of processing signals from multiple directional probes, a repeater system, and a handheld monitor system. Seismic, passive infrared (PIR), and magnetic probes are currently supported. The design of the INSENS system elements and their performance are described.

Myers, D.W.; Baker, J.; Benzel, D.M.; Fuess, D.A.

1993-09-29

340

Forming different planetary systems  

NASA Astrophysics Data System (ADS)

With the increasing number of detected exoplanet samples, the statistical properties of planetary systems have become much clearer. In this review, we summarize the major statistical results that have been revealed mainly by radial velocity and transiting observations, and try to interpret them within the scope of the classical core-accretion scenario of planet formation, especially in the formation of different orbital architectures for planetary systems around main sequence stars. Based on the different possible formation routes for different planet systems, we tentatively classify them into three major catalogs: hot Jupiter systems, standard systems and distant giant planet systems. The standard system can be further categorized into three sub-types under different circumstances: solar-like systems, hot Super-Earth systems, and subgiant planet systems. We also review the theory of planet detection and formation in binary systems as well as planets in star clusters.

Zhou, Ji-Lin; Xie, Ji-Wei; Liu, Hui-Gen; Zhang, Hui; Sun, Yi-Sui

2012-08-01

341

Qualitative Action Systems  

NASA Astrophysics Data System (ADS)

An extension to action systems is presented facilitating the modeling of continuous behavior in the discrete domain. The original action system formalism has been developed by Back et al. in order to describe parallel and distributed computations of discrete systems, i.e. systems with discrete state space and discrete control. In order to cope with hybrid systems, i.e. systems with continuous evolution and discrete control, two extensions have been proposed: hybrid action systems and continuous action systems. Both use differential equations (relations) to describe continuous evolution. Our version of action systems takes an alternative approach by adding a level of abstraction: continuous behavior is modeled by Qualitative Differential Equations that are the preferred choice when it comes to specifying abstract and possibly non-deterministic requirements of continuous behavior. Because their solutions are transition systems, all evolutions in our qualitative action systems are discrete.

Aichernig, Bernhard K.; Brandl, Harald; Krenn, Willibald

342

INMARSAT communications system: A systems approach  

NASA Astrophysics Data System (ADS)

This study describes the history of satellite communications from its beginning to the current date and explains the major components of satellite communications. It describes the satellite communications technology, and identifies some of its problems such as speech echo, data transmission, and digital network synchronization. It deals with U.S. military and international satellite communications systems, and especially with Inmarsat. It also presents the possible threats for a satellite communications system and discusses how to deal with them. Finally, it introduces some conditions and technical considerations of the Inmarsat system in the Hellenic environment and provides some basic information for choosing a satellite system from an economic point of view.

Fasoulas, Aristides I.

1991-06-01

343

Site systems engineering: Systems engineering management plan  

SciTech Connect

The Site Systems Engineering Management Plan (SEMP) is the Westinghouse Hanford Company (WHC) implementation document for the Hanford Site Systems Engineering Policy, (RLPD 430.1) and Systems Engineering Criteria Document and Implementing Directive, (RLID 430.1). These documents define the US Department of Energy (DOE), Richland Operations Office (RL) processes and products to be used at Hanford to implement the systems engineering process at the site level. This SEMP describes the products being provided by the site systems engineering activity in fiscal year (FY) 1996 and the associated schedule. It also includes the procedural approach being taken by the site level systems engineering activity in the development of these products and the intended uses for the products in the integrated planning process in response to the DOE policy and implementing directives. The scope of the systems engineering process is to define a set of activities and products to be used at the site level during FY 1996 or until the successful Project Hanford Management Contractor (PHMC) is onsite as a result of contract award from Request For Proposal DE-RP06-96RL13200. Following installation of the new contractor, a long-term set of systems engineering procedures and products will be defined for management of the Hanford Project. The extent to which each project applies the systems engineering process and the specific tools used are determined by the project`s management.

Grygiel, M.L. [Westinghouse Hanford Co., Richland, WA (United States)

1996-05-03

344

Solar energy recovery system  

SciTech Connect

A solar tracking system for a sun sensitive system such as a solar energy generating unit is described. Means for tracking the sun in bright sunlight and in cloudy conditions having a sun sensing mode and a blind mode are disclosed. Solar energy generating units compatible with the solar tracking system capable of automatically operating a stock watering system are also disclosed.

Arbogast, C.C.

1984-10-16

345

Coaches as System Leaders  

ERIC Educational Resources Information Center

The role of school leadership--of principals and coaches--must be played out on a systems level to get widespread and sustainable improvement. Successful, whole-system education reform relies on capacity building, teamwork, pedagogy, and systemic reform. The strategies of good coaches and the right drivers for whole-system reform go hand in hand.…

Fullan, Michael; Knight, Jim

2011-01-01

346

Designing Project Management Systems  

Microsoft Academic Search

The purpose of this paper is to develop the concept of project management system from the perspective of systems science. There is a need to extend the body of knowledge for project management. In particular, the application of systems perspectives and systems theory offers a significant opportunity to advance the current state of project management knowledge. Although there have been

Gamze Karayaz; Charles B. Keating; Morgan Henrie

2011-01-01

347

Automated reasoning system ITP  

Microsoft Academic Search

This report describes a system designed to provide a portable environment for the study of automated reasoning. The system is built on the LMA automated reasoning subroutine package. This program is not part of LMA itself but illustrates the level of inference-based system that can be constructed from the LMA package of tools. It is a clause-based reasoning system supporting

E. L. Lusk; R. A. Overbeek

1984-01-01

348

Polymer Electronics Systems - Polytronics  

Microsoft Academic Search

Current trends in the development of electronics systems show that the provision of thin flexible components and semiconductors plays a decisive role in the steadily progressing development of highly integrated systems. A new generation of thin flexible electronic systems arises. At Fraunhofer IZM, inline manufacturing processes for polymer electronic systems are developed on production type equipment. A low-cost process for

KARLHEINZ BOCK

2005-01-01

349

Observers for multivariable systems  

Microsoft Academic Search

Often in control design it is necessary to construct estimates of state variables which are not available by direct measurement. If a system is linear, its state vector can be approximately reconstructed by building an observer which is itself a linear system driven by the available outputs and inputs of the original system. The state vector of annth order system

D. Luenberger

1966-01-01

350

Coaches as System Leaders  

ERIC Educational Resources Information Center

|The role of school leadership--of principals and coaches--must be played out on a systems level to get widespread and sustainable improvement. Successful, whole-system education reform relies on capacity building, teamwork, pedagogy, and systemic reform. The strategies of good coaches and the right drivers for whole-system reform go hand in hand.…

Fullan, Michael; Knight, Jim

2011-01-01

351

System Reliability Sensitivity Measures  

Microsoft Academic Search

System reliability sensitivity measures are proposed to assist designers and reliability analysts in prioritizing reliability improvement and testing activities. In complex system designs, a common goal is to improve system reliability by increasing the reliability of the components to be used within the system. Component reliability is generally estimated from field failure data or test data. Unfortunately, these data are

Tongdan Jin; David W. Coit

352

Systems engineering management plan  

Microsoft Academic Search

The purpose of this Systems Engineering Management Plan (SEMP) is to prescribe the systems engineering procedures to be implemented at the Program level and the minimum requirements for systems engineering at the Program-element level. The Program level corresponds to the Director, OCRWM, or to the organizations within OCRWM to which the Director delegates responsibility for the development of the System

Conner

1985-01-01

353

Developing Systems Engineering Ontologies  

Microsoft Academic Search

Systems engineering ontologies are required to assist interested parties in understanding the systems engineering discipline's broad and multi-faceted nature. This paper discusses the need for and general benefits of an ontology. The authors discuss the use of the domain knowledge acquisition process ontology modeling technique and its application to capture a systems engineering functional domain ontology. A preliminary systems engineering

B. Sarder; S. Ferreira

2007-01-01

354

Multipurpose Visualization System  

Microsoft Academic Search

This paper deals with the design and architecture of the low cost multipurpose flight visualization system (MFVS). The MFVS system was originally developed as a passive IFR approach system for general aviation small planes. A relatively high adaptability is one of the main advantages. It can be easily used with many types of avionics devices. The GPS\\/INS system is used

P. Bojda; P. Frantis

2006-01-01

355

Computer Center: CIBE Systems.  

ERIC Educational Resources Information Center

Differentiates between computer systems and Computers in Biological Education (CIBE) systems (computer system intended for use in biological education). Describes several CIBE stand alone systems: single-user microcomputer; single-user microcomputer/video-disc; multiuser microcomputers; multiuser maxicomputer; and local and long distance computer…

Crovello, Theodore J.

1982-01-01

356

The immune system  

Microsoft Academic Search

The immune system consists of a heterogenous collection of cells that are exquisitely designed to function as a means of protection from colonization by infectious agents. The cells comprising the immune system are described as well as their development and function. The immune system is tightly regulated by a system of signals transmitted by soluble substances (interleukins) as well as

Philip J. Morrissey

1997-01-01

357

Medical imaging systems  

DOEpatents

A medical imaging system provides simultaneous rendering of visible light and diagnostic or functional images. The system may be portable, and may include adapters for connecting various light sources and cameras in open surgical environments or laparascopic or endoscopic environments. A user interface provides control over the functionality of the integrated imaging system. In one embodiment, the system provides a tool for surgical pathology.

Frangioni, John V

2013-06-25

358

Stability of hybrid systems  

Microsoft Academic Search

We introduce a model of hybrid systems as a combination of discrete state and continuous state systems. The continuous state space is divided into regions so that in every region, depending on the discrete state of hybrid system, the continuous state system dynamic functions which are called representative functions are found. The switching situation in a region is studied and

Murat Dogruel; Umit Ozguner

1994-01-01

359

Integrated library systems.  

PubMed

The development of integrated library systems is discussed. The four major discussion points are (1) initial efforts; (2) network resources; (3) minicomputer-based systems; and (4) beyond library automation. Four existing systems are cited as examples of current systems. PMID:6354321

Goldstein, C M

1983-07-01

360

Electronic Document Supply Systems.  

ERIC Educational Resources Information Center

|Describes electronic document delivery systems used by libraries and document image processing systems used for business purposes. Topics discussed include technical specifications; analogue read-only laser videodiscs; compact discs and CD-ROM; WORM; facsimile; ADONIS (Article Delivery over Network Information System); DOCDEL; and systems at the…

Cawkell, A. E.

1991-01-01

361

The IRIDIUM communications system  

Microsoft Academic Search

A description is given of the IRIDIUM communication system, so-called because the system design originally consisted of 77 networked satellites, and the element iridium has the atomic number 77. The goal is to make instant global communications a reality. The system design now consists of 60 satellites, a system control facility, gateways, and subscriber units. Each of these components is

R. J. Leopold; A. Miller

1993-01-01

362

Vehicle tracking systems  

SciTech Connect

Several systems have been developed to accomplish vehicle location. The systems consist of three types: Dead Reckoning, Satellite, and LORAN C. If the information is to be sent back to a central location, some type of radiocommunication system is needed. One can use the existing voice radio or add a radio system just for transmitting the data.

Schwalm, R.W.

1987-01-01

363

Broad Bandwidth Telecommunications Systems.  

ERIC Educational Resources Information Center

|Broad bandwidth transmission systems have been around for years. They include microwave, assorted cable systems, and recently, satellites. With the exception of some privately owned systems, broadband services have been furnished by the common carriers. Recently, a new element has been added--Cable Antenna Television (CATV) distribution systems.…

Sodolski, John

364

Corba for control systems  

Microsoft Academic Search

The Common Project Request Broker Architecture (CORBA) is a middle-ware specification for the development of interoperable, distributed object systems. Object technology is of extreme importance in complex control system development besides its progressive use in other types of real-time systems. This paper tries to provide a general overview of the topics in distributed object systems, focusing on CORBA aspects that

Ricardo Sanz; Mariano Alonso

2001-01-01

365

Parameterised boolean equation systems  

Microsoft Academic Search

Boolean equation system are a useful tool for verifying formulas from modal mu-calculus on transition systems (see (18) for an excellent treatment). We are interested in an extension of boolean equation systems with data. This allows to formulate and prove a substantially wider range of properties on much larger and even infinite state systems. In previous works (11, 15) it

Jan Friso Groote; Tim A. C. Willemse

2005-01-01

366

Linear Systems: Using Algebra  

NSDL National Science Digital Library

Students learn to solve a system of linear equations (2 equations with 2 variables) by substitution and elimination methods. They also review the definitions of consistent (independent and dependent) and inconsistent systems, and associate the number of solutions of a system with them. Detailed instructions guide students in using their graphing calculators to solve the systems of equations.

2009-06-14

367

Digital Storage System.  

National Technical Information Service (NTIS)

The digital storage system has a short access time and a high read-out rate. It is used in burst communication systems. The system is a binary-coded digital system and it employs a plurality of dynamic storage lines, one of which is used to store index bi...

H. L. Heibeck C. G. Wilhelm W. M. Oleson

1966-01-01

368

Graduate Grading Systems.  

ERIC Educational Resources Information Center

|A questionnaire on grading systems was sent to the 287 members of the Council of Graduate Schools. Of the 240 responses, 127 indicated that they used systems other than the A-F traditional system, either in part or in toto. Other systems used include pass/fail, satisfactory/unsatisfactory, pass/no credit, and some variations of the A-F…

Benson, Winston W.

369

Japan's new solid-rocket booster and its derivative launcher  

NASA Astrophysics Data System (ADS)

The current status of the design and development of the Japanese H-II SRB and its derivative launch vehicle is presented. Four full-scale static firing tests of the solid rocket motor have been conducted and the flight hardware is presently in production. Attention is given to the solid rocket booster configuration, design features, thrust vector control, and component development.

Miyazawa, Masafumi; Fukushima, Yukio; Miyaba, Hiroshi; Hosomura, Tateo; Asai, Tatsuro

1992-08-01

370

Studies of energy management technology of solid rocket motors  

Microsoft Academic Search

This paper presents the advantages of using solid rocket motors with energy management technology in tactical missiles. The special kind of rocket motor provides significant expansion of missile flight altitude and range. The energy management features of rocket motors permit airframes with reduced wing size, weight and drag, and also provide the possibility of thrust vector control for end-game maneuvering

Jinqi Yin

1993-01-01

371

Solid rocket motor nozzle flexseal design sensitivity  

Microsoft Academic Search

On solid rocket motors, direction is controlled by controlling the thrust vector. To achieve this, the nozzle usually incorporates a flexseal that allows the nozzle to vector (or rotate) in any direction. The flexseal has a core of alternating layers of elastomer pads and metal or composite shims. Flexseal core design is an iterative process. An estimate of the flexseal

James R. Donat

1993-01-01

372

Design of Supersonic Coanda Jet Nozzles.  

National Technical Information Service (NTIS)

The thrust vectoring of supersonic Coanda jets was improved by designing a nozzle to skew the initial jet velocity profile. A new nozzle design procedure, based on the method of characteristics, was developed to design a nozzle which produces a specified ...

P. M. Bevilaqua J. D. Lee

1987-01-01

373

Hybrid electrical power source testing for electromechanical actuation applications  

Microsoft Academic Search

New technology Launch vehicle programs such as the Reusable Launch Vehicle (RLV)X-33 and the Evolutionary Expendable Launch Vehicle (EELV), have the desire to incorporate electromechanical actuator (EMA) technology for thrust vector control (TVC), aerosurface control and propellant flow valves. A major part of this technology advancement lies in power source selection, development and testing. The challenge for EMA power sources

D. K. Hall; S. D. Layton

1996-01-01

374

Nonlinear dynamics of a vectored thrust aircraft  

Microsoft Academic Search

With realistic relations for the aerodynamic coefficients, numerical simulation is applied to study the longitudinal dynamics of a vectored thrust aircraft in the post-stall regime. As function of the thrust magnitude and the thrust vectoring angle the equilibrium state exhibits three Hopf bifurcations and two saddle-node bifurcations. Even when the equilibrium is stable, weakly damped oscillations occur with a period

Claus B. Sørensen; Erik Mosekilde; Péter Gránásy

1996-01-01

375

PARAMETRIC MODEL OF AN AEROSPIKE ROCKET ENGINE  

Microsoft Academic Search

A suite of computer codes was assembled to simulate the performance of an aerospike engine and to generate the engine input for the Program to Optimize Simulated Trajectories. First an engine simulator module was developed that predicts the aerospike engine performance for a given mixture ratio, power level, thrust vectoring level, and altitude. This module was then used to rapidly

J. J. Korte

2000-01-01

376

Development and test of a two-axis force transducer  

Microsoft Academic Search

A two-axis force transducer to measure axial thrust and side force in a thrust vector nozzle is described. The transducer incorporates two mutually perpendicular steel cantilever beams into a single unit. Strain gages mounted on each beam are used to convert beam deflections into electrical signals proportional to the axial thrust and side force. The outputs of the gages are

B. G. Brown; M. E. Franke; J. W. Cates; W. R. Cox

1988-01-01

377

Computational investigation on infrared radiation characteristic for two-dimensional vectoring nozzles with fluidic injection  

Microsoft Academic Search

Relative to the thrust vectoring nozzle by mechanical means, fluidic injection vectoring nozzle outshines on the strength of uncomplicated structure, light weight and low cost. Research on infrared characteristic of fluidic injection vectoring nozzles is highly vital for nozzle technology development and military application. Numerical simulation for infrared characteristic of the two-dimensional fluidic injection vectoring nozzles was conducted employing self-developed

Guanqun Kang; Qiang Wang

2011-01-01

378

CFD-simulation of the flow through a fluidic element  

Microsoft Academic Search

The outflow channel of the fluidic jet reaction control element (FLE) and hence the direction of the thrust vector may be controlled by the injection of a secondary jet through one of the slits downstream of the inlet nozzle in the side walls. The main medium used is gaseous nitrogen, which is supplied from a reservoir chamber. Depending on the

Uwe Reisch; Rosemarie Meuer

2000-01-01

379

Development of a micro-nozzle and ion mobility spectrometer in LTCC  

Microsoft Academic Search

Multilayer ceramic packaging materials provide a versatile platform to fabricate a wide variety of devices from sensors to micro-nozzles. Our research is focused on developing robust sensors for underground deployment and monopropellant micro nozzles for satellite attitude adjustment applications. An LTCC monopropellant micro-nozzle is being developed and tested to provide small thrust vectors for satellite attitude adjustments. High purity hydrogen

Donald Plumlee; Judi Steciak; Amy Moll

2004-01-01

380

The Effect Of Counterflow On The Acoustic Characteristics Of A Mach 1.44 Rectangular Jet  

Microsoft Academic Search

The application of counterflow around the periphery of a jet has been used to achieve elevated mixing levels in compressible shear layers and to provide fluidic thrust vector control of supersonic jets. Due to these benefits, an investigation is undertaken to determine the effect of counterflow on the acoustic properties of supersonic jets. Specifically, the aeroacousitc properties of a Mach

C. Shih; F. S. Alvi; A. Krothapalli

1996-01-01

381

Shuttle Reference Data  

NASA Astrophysics Data System (ADS)

This collection of shuttle reference data contains the following information: shuttle abort history, shuttle abort modes, abort decisions, space shuttle rendezvous maneuvers, space shuttle main engines, space shuttle solid rocket boosters, hold-down posts, SRB (solid rocket boosters) ignition, electrical power distribution, hydraulic power units, thrust vector control, SBR rate gyro assemblies, SBR separation and Space Shuttle Super Super Light Weight Tank (SLWT).

2002-12-01

382

EPICS system: system structure and user interface  

SciTech Connect

This paper present the user's view of and the general organization of the EPICS control system at Fermilab. Various subsystems of the EPICS control system are discussed. These include the user command language, software protection, the device database, remote computer interfaces, and several application utilities. This paper is related to two other papers on EPICS: an overview paper and a detailed implementation paper.

West, R.E.; Bartlett, J.F.; Bobbitt, J.S.; Lahey, T.E.; Kramper, B.J.; MacKinnon, B.A.

1984-02-01

383

Joint Tactical Radio System - Enterprise System Engineering  

Microsoft Academic Search

The Joint Tactical Radio System (JTRS) is a core transformational program within the Department of Defense (DoD), critical to extending the Global Information Grid (GIG) to the tactical edge. The Joint Program Executive Office (JPEO) was established in 2005 to manage the development of JTRS. One of the JPEO's assigned responsibilities was to expand the approach to systems engineering across

Richard North; Calvin Vu; Tom Woodland

2007-01-01

384

An expert system for power systems maintenance  

Microsoft Academic Search

When power equipment fails, maintenance personnel have traditionally had to investigate and repair the equipment by using information supplied by supervision and control systems, specified in manuals, or gained through personal experience. To enable maintenance personnel to respond more quickly and accurately, the authors have developed an expert system (called ALICE-ES), that provides diagnostic expert know-how and emergency procedures arranged

A. Mitsuhashi; T. Maruyama; H. Inoue; T. Takeda

1993-01-01

385

Evolving Information Systems: Beyond Temporal Information Systems  

Microsoft Academic Search

Nowadays, in order for an organisation to be competitive, it must be able to adapt quickly to its dynamic environment. In this paper, we discuss the need for information systems which are capable to evolve to the same extent as organisations do. Requirements of evolving organisations on their in- formation systems are identied, followed by alternative approaches to adequate information

Eckhard D. Falkenberg; J. L. Han Oei; Henderik Alex Proper

1992-01-01

386

System identification of nonlinear resonant systems  

Microsoft Academic Search

This dissertation addresses the problem of thermo-acoustic combustion instability modelling using nonlinear system identification. Specifically we are interested in the identification of closed loop limit cycling systems composed of a linear transfer function with a static nonlinearity in feedback. To begin we address the feasibility of the identification task, in terms of both data quality and dynamical capabilities of the

Wayne John Dunstan

2003-01-01

387

Electric system restructuring and system reliability  

Microsoft Academic Search

In 1996 the California legislature passed AB 1890, explicitly defining economic benefits and detailing specific mechanisms for initiating a partial restructuring the state's electric system. Critics have since sought re-regulation and proponents have asked for patience as the new institutions and markets take shape. Other states' electric system restructuring activities have been tempered by real and perceived problems in the

Catherine Miller Horiuchi

2001-01-01

388

Performance, Performance System, and High Performance System  

ERIC Educational Resources Information Center

|This article proposes needed transitions in the field of human performance technology. The following three transitions are discussed: transitioning from training to performance, transitioning from performance to performance system, and transitioning from learning organization to high performance system. A proposed framework that comprises…

Jang, Hwan Young

2009-01-01

389

Subobject Transformation Systems and Elementary Net Systems  

Microsoft Academic Search

Graph transformation systems (GTSs) (10) are a powerful specification formal- ism for concurrent and distributed systems, generalising another classical model of concurrency, namely Place\\/Transition Petri nets (8). Along the years, the con- current behaviour of GTSs has been deeply studied and a consolidated theory of concurrency is now available. In particular, by exploiting the relationship with Petri nets, several concurrent

Andrea Corradini; Frank Hermann

390

Vending machine accountability system  

US Patent & Trademark Office Database

An accountability system for a vending machine system having means for vending products and means for determining credit, the accountability system comprising a portable electronic data file module which is removable from the system, and means for collecting transaction data from the vending machine system and recording it in the portable electronic data file module. A module interlock and a power monitor are provided to ensure that accurate information is stored in the module.

1981-06-09

391

Identification of hybrid systems  

Microsoft Academic Search

Hybrid or continuous\\/discrete systems have attracted increased scientific attention in recent years. In fact, most technical systems consist of physical (sub)systems which are governed by continuous dynamics, continuous or discrete-time controllers, and logical systems which react to and trigger events in the continuous parts. Hybrid systems also arise from modeling of physical phenomena alone, e.g. in evaporation and other processes

Ingo Hoffmann; Sebastian Engell

1998-01-01

392

System of Systems Enterprise Systems Engineering, the Enterprise Architecture Management Framework, and System of Systems Cost Estimation  

Microsoft Academic Search

Today's need for more complex, more capable systems in a short timeframe is leading more organizations towards the integration of existing systems, Commercial-Off-the-Shelf (COTS) products, and new systems into network-centric, knowledge-based Systems of Systems (SoSs). With this development approach, system development processes to define the new architecture, identify sources to either supply or develop the required components, and eventually integrate

Paul Carlock

2006-01-01

393

On evolutionary systems.  

PubMed

This paper develops a metatheoretical framework for understanding evolutionary systems (systems that develop in ways that increase their own variety). The framework addresses shortcomings seen in other popular systems theories. It concerns both living and nonliving systems, and proposes a metahierarchy of hierarchical systems. Thus, it potentially addresses systems at all descriptive levels. We restrict our definition of system to that of a core system whose parts have a different ontological status than the system, and characterize the core system in terms of five global properties: minimal length interval, minimal time interval, system cycle, total receptive capacity, and system potential. We propose two principles through the interaction of which evolutionary systems develop. The Principle of Combinatorial Expansion describes how a core system realizes its developmental potential through a process of progressive differentiation of the single primal state up to a limit stage. The Principle of Generative Condensation describes how the components of the last stage of combinatorial expansion condense and become the environment for and components of new, enriched systems. The early evolution of the Universe after the "big bang" is discussed in light of these ideas as an example of the application of the framework. PMID:3689299

Alvarez de Lorenzana, J M; Ward, L M

1987-01-01

394

Enhanced nurse call systems.  

PubMed

This Evaluation focuses on high-end computerized nurse call systems--what we call enhanced systems. These are highly flexible systems that incorporate microprocessor and communications technologies to expand the capabilities of the nurse call function. Enhanced systems, which vary in configuration from one installation to the next, typically consist of a basic system that provides standard nurse call functionality and a combination of additional enhancements that provide the added functionality the facility desires. In this study, we examine the features that distinguish enhanced nurse call systems from nonenhanced systems, focusing on their application and benefit to healthcare facilities. We evaluated seven systems to determine how well they help (1) improve patient care, as well as increase satisfaction with the care provided, and (2) improve caregiver efficiency, as well as increase satisfaction with the work environment. We found that all systems meet these objectives, but not all systems perform equally well for all implementations. Our ratings will help facilities identify those systems that offer the most effective features for their intended use. The study also includes a Technology Management Guide to help readers (1) determine whether they'll benefit from the capabilities offered by enhanced systems and (2) target a system for purchase and equip the system for optimum performance and cost-effective operation. PMID:11382209

2001-04-01

395

Modeling Power Systems as Complex Adaptive Systems  

SciTech Connect

Physical analogs have shown considerable promise for understanding the behavior of complex adaptive systems, including macroeconomics, biological systems, social networks, and electric power markets. Many of today's most challenging technical and policy questions can be reduced to a distributed economic control problem. Indeed, economically based control of large-scale systems is founded on the conjecture that the price-based regulation (e.g., auctions, markets) results in an optimal allocation of resources and emergent optimal system control. This report explores the state-of-the-art physical analogs for understanding the behavior of some econophysical systems and deriving stable and robust control strategies for using them. We review and discuss applications of some analytic methods based on a thermodynamic metaphor, according to which the interplay between system entropy and conservation laws gives rise to intuitive and governing global properties of complex systems that cannot be otherwise understood. We apply these methods to the question of how power markets can be expected to behave under a variety of conditions.

Chassin, David P.; Malard, Joel M.; Posse, Christian; Gangopadhyaya, Asim; Lu, Ning; Katipamula, Srinivas; Mallow, J V.

2004-12-30

396

Systems Engineering for Large-Scale Fingerprint Systems  

Microsoft Academic Search

Systems engineering for large-scale Automated Fingerprint Recognition Systems (AFIS) involves system planning, specification,\\u000a design, development, testing, and operational support. Testing these systems includes the complex activity of measuring the\\u000a system’s performance. The desired system performance, however, affects each of the system’s engineering functions. For large-scale\\u000a systems, estimating the performance of the full-scale operational system and planning for its development are

Rajiv Khanna

397

Verification of Adaptive Systems  

SciTech Connect

Adaptive systems are critical for future space and other unmanned and intelligent systems. Verification of these systems is also critical for their use in systems with potential harm to human life or with large financial investments. Due to their nondeterministic nature and extremely large state space, current methods for verification of software systems are not adequate to provide a high level of assurance for them. The combination of stabilization science, high performance computing simulations, compositional verification and traditional verification techniques, plus operational monitors, provides a complete approach to verification and deployment of adaptive systems that has not been used before. This paper gives an overview of this approach.

Pullum, Laura L [ORNL; Cui, Xiaohui [New York Institute of Technology (NYIT); Vassev, Emil [Lero – The Irish Software Engineering Research Centre; Hinchey, Mike [Lero – The Irish Software Engineering Research Centre; Rouff, Christopher [Lockheed Martin Corporation; Buskens, Richard [Lockheed Martin Corporation

2012-01-01

398

FPD plasma heating systems  

SciTech Connect

Tandem mirror devices rely on a number of plasma heating systems to create and maintain potential and density profiles which axially confine the central cell and provide MHD stability. The Fusion Power Demonstrator (FPD) tandem mirror study was carried out in three stages, each facility was configured with a slightly different mission and set of constraints. Although the heating system requirements varied in the three stages, the potential peak and thermal barrier ECRH systems and the sloshing ion neutral beam system were common elements of the configurations. The heating systems' requirements, the design approach, and the systems' description are presented.

Freije, S.A.

1985-07-01

399

On maximally superintegrable systems  

NASA Astrophysics Data System (ADS)

Locally any completely integrable system is maximally superintegrable system since we have the necessary number of the action-angle variables. The main problem is the construction of the single-valued additional integrals of motion on the whole phase space by using these multi-valued action-angle variables. Some constructions of the additional integrals of motion for the Stäckel systems and for the integrable systems related with two different quadratic r-matrix algebras are discussed. Among these system there are the open Heisenberg magnet and the open Toda lattices associated with the different root systems.

Tsiganov, A. V.

2008-06-01

400

Modern signals and systems  

NASA Astrophysics Data System (ADS)

The present text on input-output and input-output mapping systems discusses elementary operations on and among time signals, delta functions, the stability of convolution systems, the definition and examples of difference and differential systems, the state description of systems, and linear time-invariant systems with periodic inputs. Also treated are discrete-to-discrete and continuous-to-discrete Fourier transforms, the z- and Laplace transforms, the design of FIR and IIR filters, modulation and demodulation methods, and feedback theory and the stability of feedback systems.

Kwakernaak, Huibert; Sivan, Raphael

401

Introducing Systems Approaches  

NASA Astrophysics Data System (ADS)

Systems Approaches to Managing Change brings together five systems approaches to managing complex issues, each having a proven track record of over 25 years. The five approaches are: System Dynamics (SD) developed originally in the late 1950s by Jay Forrester Viable Systems Model (VSM) developed originally in the late 1960s by Stafford Beer Strategic Options Development and Analysis (SODA: with cognitive mapping) developed originally in the 1970s by Colin Eden Soft Systems Methodology (SSM) developed originally in the 1970s by Peter Checkland Critical Systems Heuristics (CSH) developed originally in the late 1970s by Werner Ulrich

Reynolds, Martin; Holwell, Sue

402

SUBSURFACE EMPLACEMENT TRANSPORTATION SYSTEM  

SciTech Connect

The objective of this analysis is to identify issues and criteria that apply to the design of the Subsurface Emplacement Transportation System (SET). The SET consists of the track used by the waste package handling equipment, the conductors and related equipment used to supply electrical power to that equipment, and the instrumentation and controls used to monitor and operate those track and power supply systems. Major considerations of this analysis include: (1) Operational life of the SET; (2) Geometric constraints on the track layout; (3) Operating loads on the track; (4) Environmentally induced loads on the track; (5) Power supply (electrification) requirements; and (6) Instrumentation and control requirements. This analysis will provide the basis for development of the system description document (SDD) for the SET. This analysis also defines the interfaces that need to be considered in the design of the SET. These interfaces include, but are not limited to, the following: (1) Waste handling building; (2) Monitored Geologic Repository (MGR) surface site layout; (3) Waste Emplacement System (WES); (4) Waste Retrieval System (WRS); (5) Ground Control System (GCS); (6) Ex-Container System (XCS); (7) Subsurface Electrical Distribution System (SED); (8) MGR Operations Monitoring and Control System (OMC); (9) Subsurface Facility System (SFS); (10) Subsurface Fire Protection System (SFR); (11) Performance Confirmation Emplacement Drift Monitoring System (PCM); and (12) Backfill Emplacement System (BES).

T. Wilson; R. Novotny

1999-11-22

403

Multisensor fusion for autonomous UAV navigation based on the Unscented Kalman Filter with Sequential Measurement Updates  

Microsoft Academic Search

This paper describes a new filtering framework of multisensor fusion and its application to the low-cost strapdown inertial navigation system of an Unmanned Aerial Vehicle (UAV). The navigation system fuses various sources of sensor information from low-cost sensor suites such as an Inertial Measurement Unit (IMU), a Global Positioning System (GPS), and a three-axis magnetometer in the new framework of

Seung-Min Oh

2010-01-01

404

Weapons Systems Development Decision Support System.  

National Technical Information Service (NTIS)

Defense budget cuts and the recent peace dividend have made weapons systems development decisions increasingly more difficult and subject to scrutiny. Meticulous planning is required to ensure tax dollars are spent wisely and effectively. This thesis pres...

R. K. Boyd

1992-01-01

405

Power Systems Development Facility, PFBC system perspectives.  

National Technical Information Service (NTIS)

Southern Company Services (SCS) has investigated the feasibility of constructing a Power Systems Development Facility (PSDF) at the Southem Company's Clean Coal Research Center in Wilsonville, Alabama. The PSDF combines a number of pilot-scale test facili...

G. H. Griswold T. J. Boyd M. O. Fankhanel C. J. Crumm D. H. Pontius

1993-01-01

406

Power Systems Development Facility, PFBC system perspectives  

SciTech Connect

Southern Company Services (SCS) has investigated the feasibility of constructing a Power Systems Development Facility (PSDF) at the Southem Company`s Clean Coal Research Center in Wilsonville, Alabama. The PSDF combines a number of pilot-scale test facilities at a single site to reduce the overall capital and operating cost compared to individual stand-alone facilities, while continuing the DOE/METC`s objective of carrying out meaningful systems and component testing for advanced coal-based power generation development. The intent of the PSDF is to provide a flexible test facility that can be used to develop advanced power system components and assess the integration and control issues of these advanced power systems. The facility would provide a resource for rigorous, long-term testing and performance assessment of hot stream cleanup devices in an integrated environment, permitting evaluation of not only the cleanup devices but also other components in an integrated operation.

Griswold, G.H. [Southern Co. Services, Inc., Birmingham, AL (United States); Boyd, T.J. [Electric Power Research Inst., Palo Alto, CA (United States); Fankhanel, M.O. [Kellogg (M.W.) Co. (United States); Crumm, C.J. [Foster Wheeler Corp. (United States); Pontius, D.H. [SRI International, Menlo Park, CA (United States)

1993-09-01

407

Power system applications for PASC converter systems.  

National Technical Information Service (NTIS)

This paper shows, using computer EMTP simulations, some preliminary results of applying pulse amplitude synthesis and control (PASC) technology to single-source level voltage converter system. The method can be applied to any single terminal pair source w...

M. K. Donnelly R. M. Johnson

1994-01-01

408

Computer Based Systems Engineering Workshop  

Microsoft Academic Search

Modern computer based systems are complex multi-systems consisting of many connected individual subsystems; each one of them is typically also a multicomputer system. The subsystems in a multi-system can be either geographically distributed or locally connected systems. Typical examples of computer based systems are medical systems, process control systems, communications systems, weapon systems and large information systems.\\u000a The development of

Jonah Z. Lavi; Ashok K. Agrawala; Raymond J. A. Buhr; Ken Jackson; Michael Jackson; Bernard Lang

1991-01-01

409

Operating system support for multimedia systems  

Microsoft Academic Search

Distributed multimedia applications will be an important part of tomorrow's application mix and require appropriate operating system (OS) support. Neither hard real-time solutions nor best-effort solutions are directly well suited for this s upport. One reason is the c o- existence of real-time and best effort requirements in future systems. Another reason is that the requirements of multimedia applications are

Thomas Plagemann; Vera Goebel; Pål Halvorsen; Otto J. Anshus

2000-01-01

410

General Curvilinear Coordinate Systems.  

National Technical Information Service (NTIS)

The basic ideas of the construction and use of numerically-generated boundary-fitted coordinate systems for the numerical solution of partial differential equations are discussed. With such coordinate systems, all computation can be done on a fixed square...

J. F. Thompson

1982-01-01

411

Switching System Simulator.  

National Technical Information Service (NTIS)

Switching System Simulator (SSS) is a CDC 6600 computer program which simulates and evaluates networks of interconnected switching elements. SSS determines all the possible ways in which a given switching system can complete a set of input/output connecti...

C. R. Williams

1976-01-01

412

Inertial Navigational Systems.  

National Technical Information Service (NTIS)

A semi-technical discussion is given of operating conditions, interaction of separate units and causes of errors of inertial guidance and navigational systems. Considerable attention is given to analysis of the operation of inertial systems under conditio...

V. S. Frolov

1964-01-01

413

Inductive System Health Monitoring.  

National Technical Information Service (NTIS)

The Inductive Monitoring System (IMS) software was developed to provide a technique to automatically produce health monitoring knowledge bases for systems that are either difficult to model (simulate) with a computer or which require computer models that ...

D. L. Iverson

2004-01-01

414

Heliostat Beam Characterization System.  

National Technical Information Service (NTIS)

The beam Characterization System utilizes video radiometer techniques to quantitatively describe the solar energy projected by a heliostat. This system is designed to evaluate prototype heliostats and to improve the performance of the Central Receiver Tes...

E. D. Thalhammer G. S. Phipps

1979-01-01

415

Avian respiratory system disorders  

USGS Publications Warehouse

Diagnosing and treating respiratory diseases in avian species requires a basic knowledge about the anatomy and physiology of this system in birds. Differences between mammalian and avian respiratory system function, diagnosis, and treatment are highlighted.

Olsen, G.H.

1989-01-01

416

Geocoded Imagery Production System.  

National Technical Information Service (NTIS)

Tne Environmental Research Institute of Michigan (ERIM) successfully designed, configured, implemented, documented, and tested a Geocoded Imagery Production System (GIPS) for the 480th Intelligence Group (IG), Langley Air Force Base, Virginia. The system ...

O. Mykolenko J. A. Sieffert

1996-01-01

417

Airborne Battle Management System.  

National Technical Information Service (NTIS)

The Navy under the Airborne Battle Management System (ABMS) program, sponsored by ONR Code 311 (Command, Control and Combat Systems) and executed by NAVAIR, is addressing the shifting focus of naval operations to power projection in a littoral environment...

G. Mersten

2000-01-01

418

Security Systems Division  

Center for Drug Evaluation (CDER)

Text Version3 Security Systems Division Security Systems Division ... the product has been handled by trusted supply chain partners? Optimized Security Solution ... More results from www.fda.gov/downloads/drugs/drugsafety

419

Chemical Thermal Desorption System.  

National Technical Information Service (NTIS)

A field portable chemical thermal desorption system. The system comprises a desorption tube, an injection needle operatively connected to the desorption tube, a needle valve operatively connected to the injection needle, a heater operatively connected to ...

A. Alcaraz C. Koester J. D. Eckels

2004-01-01

420

Operations Management System.  

National Technical Information Service (NTIS)

The objective of an operations management system is to provide an orderly and efficient method to operate and maintain aerospace vehicles. Concepts are described for an operations management system and the key technologies are highlighted which will be re...

A. E. Brandli R. E. Eckelkamp C. M. Kelly W. Mccandless D. L. Rue

1990-01-01

421

Emergency Cooling System Flows.  

National Technical Information Service (NTIS)

Calculations of emergency cooling system (ECS) flows are required to complete the Flood Code documentation and validation. Only minimum ECS flows are required input to the FLOOD code for system safety analysis. ECS flows have not been documented since the...

J. H. Hinton

1985-01-01

422

Hydrographic Winch System.  

National Technical Information Service (NTIS)

This report contains a complete physical and operational description of a hydrographic winch system developed at NOTS. Significant design features and operational parameters of the winch are given; the functions of the components of the system are discuss...

R. Hearn

1967-01-01

423

Autonomous Flight Safety System.  

National Technical Information Service (NTIS)

Autonomous Flight Safety System (AFSS) is an independent flight safety system designed for small to medium sized expendable launch vehicles launching from or needing range safety protection while overlying relatively remote locations. AFSS replaces the ne...

B. Bull B. Ferrell J. Lanzi J. Simpson R. Zoerner S. Santuro

2004-01-01

424

CACTUS: System Documentation.  

National Technical Information Service (NTIS)

Systems documentation is provided for the Client Action, Characteristics, Tracking and Record Updating System (CACTUS), which was transferred from Kansas City, Missouri, to assist managers and planners of youth service programs in Los Angeles County, Cali...

1975-01-01

425

Silver recovery system data  

SciTech Connect

In August of 1990 the Savannah River Site Photography Group began testing on a different type of silver recovery system. This paper describes the baseline study and the different phases of installation and testing of the system.

Boulineau, B.

1991-08-26

426

Immune System and Disorders  

MedlinePLUS

Your immune system is a complex network of cells, tissues, and organs that work together to defend against germs. It ... t, to find and destroy them. If your immune system cannot do its job, the results can be ...

427

Pneumonia - weakened immune system  

MedlinePLUS

... to fight infection is greatly reduced because their immune system is weakened and not working properly. Such disease ... People whose immune system is not working well are less able to fight off germs. Because of this state, they are more ...

428

Our Immune System  

MedlinePLUS

... story for children with primary immunodeficiency diseases Our Immune System Our Immune IMMUNE DEFICIENCY FOUNDATION A note from ... who are immune deficient to better understand their immune system. What is a “B-cell,” a “T-cell,” ...

429

Python Microgravity Accelerometer System.  

National Technical Information Service (NTIS)

Scientists performing experiments in the unique microgravity environment of space frequently require an accurate and useful view of the acceleration at their experiment. Payload Systems has developed a Microgravity Accelerometer System for use in the Spac...

V. Nijhawan A. P. Arrott

1988-01-01

430

Unmanned Systems Interoperability.  

National Technical Information Service (NTIS)

Mission: Lead the development, systems engineering, integration, acquisition, testing, fielding, sustainment and improvement of unmanned systems for the Joint Warfighter to ensure safe, effective and supportable capabilities are provided while meeting cos...

C. Smith

2010-01-01

431

Flight Control Systems Research.  

National Technical Information Service (NTIS)

Theoretical development is reported for the parameter optimization design technique needed for digital flight control system design. The results of an example case study applying the optimization technique for continuous systems to an F-8 aircraft feedbac...

H. P. Whitaker Y. Baram Y. Cheng

1973-01-01

432

Computer system administrator  

NSDL National Science Digital Library

Teachers can direct students to this material to help them investigate a career as a computer systems analyst, particularly as a computer systems administrator. Having students review this page can be an excellent precursor to a job-shadowing activity.

Project, Iowa P.

2002-01-01

433

UNIFORM DATA SYSTEM (UDS)  

EPA Science Inventory

This data collection system collects uniformly-defined information for the major BPHC grant programs. The system yields consistent information on patient characteristics and clinical conditions. The UDS provides data on services, site locations, delivery methods, staffing, client...

434

Whole Body Measurement System.  

National Technical Information Service (NTIS)

A biomedical system for quantitatively determining the volume and volume change of a human body under weightlessness conditions, over a period of time, is described. The system consists of an enclosed chamber having a defined volume and arranged for recei...

J. S. Ogle

1971-01-01

435

Geographic Information Systems, 1990.  

National Technical Information Service (NTIS)

Contents: Potential for geographic information systems in transportation planning and highway infrastructure management; Using geographic information system technology to enhance the pavement management process; Pavement management applications of GIS: A ...

N. C. Kassabian A. G. Tobias L. Caryton K. Solomon N. Solomon

1990-01-01

436

Microelectronics Bioinstrumentation Systems.  

National Technical Information Service (NTIS)

Microelectronic bioinstrumentation systems to be employed in the Cardiovascular Deconditioning Program were developed. Implantable telemetry systems for long-term monitoring of animals on earth were designed to collect physiological data necessary for the...

W. H. Ko

1977-01-01

437

Microelectronic Bioinstrumentation System.  

National Technical Information Service (NTIS)

The progess made from April 1973 to June 1974 on a microelectronics bioinstrumentation system is reported and includes data for the following three individual projects: (1) a radio frequency powered implant telemetry system; (2) an ingestible temperature ...

W. H. Ko E. T. Yon R. J. Rodriguez

1974-01-01

438

Shaping Educational Accountability Systems.  

ERIC Educational Resources Information Center

Discusses shaping educational accountability systems in the context of the No Child Left Behind Act of 2001. Suggests ways in which evaluation can contribute to improving and changing accountability systems, especially through the development of standards. (SLD)

Ryan, Katherine

2002-01-01

439

Johnson Transformation System Revisited.  

National Technical Information Service (NTIS)

Some results on the Johnson transformation system are obtained which can enhance applications of this system in multivariate Monte Carlo studies. The primary contribution is that the mean vector and the covariance matrix in the transformed population can ...

M. E. Johnson J. S. Ramberg

1977-01-01

440

FTD Edit System.  

National Technical Information Service (NTIS)

A 16-terminal, interactive, text processing system is described. The system was designed for post processing of computer translated Russian scientific and technical literature. Sophisticated word processing software is supported on 5 minicomputers organiz...

R. Case L. Berglund

1976-01-01

441

Implantable Insulin Delivery System.  

National Technical Information Service (NTIS)

An insulin delivery system suitable for experimental implants and external use has been developed to study glucose control for diabetics. The programmable system developed at Sandia National Laboratories, in conjunction with the University of New Mexico S...

J. T. Love J. I. Gaona

1981-01-01

442

Developing Expert Systems.  

National Technical Information Service (NTIS)

The document provides a set of general guidelines for the development and distribution of highway related expert systems. This expands the guidelines provided in Chapter X, Expert Systems, of the ADP Management Manual. Included is information on developin...

D. Barnett C. Jackson J. A. Wentworth

1988-01-01

443

Clandestine Communication Systems.  

National Technical Information Service (NTIS)

Subversive elements, whether insurgent, terrorist, or criminal, all require a communication system to coordinate and control operations. The development of a clandestine communication system requires special considerations in the development of the nodes ...

J. T. COrley

2001-01-01

444

Integrated Library System (ILS).  

National Technical Information Service (NTIS)

The Integrated Library System (ILS) is a minicomputer-based library automation system designed to support a full range of technical processing and retrieval activities using a single master bibliographic file, (MBF). Current subsystems include: Bibliograp...

C. M. Goldstein R. Borochoff

1981-01-01

445

Imaging system (INEL)  

SciTech Connect

This progress report gives a brief description of the general automatic target recognition system algorithms developed for this project, and also summarizes the progress in fiscal 1991. An appendix discusses the proposed computer hardware for this system.

Partin, J.K.; Lassahn, G.D.; Davidson, J.R.

1991-10-01

446

LIGHTWEIGHT GREEN ROOF SYSTEMS  

EPA Science Inventory

Applying a Lightweight Green Roof System to a building can achieve in managing storm water runoff, decreasing heat gain, yielding energy savings, and mitigating the heat island effect. Currently, Most green roof systems are considerably heavy and require structural reinforceme...

447

Systems Theory and Astrobiology  

NASA Astrophysics Data System (ADS)

The breadth and topics of astrobiology provide a testing ground for exploring systems concepts. Currently astrobiology to deal with the question "What is life?" Systems thinking offers a way of breaking out of our mental box.

Woolf, N., J.

2010-04-01

448

Central nervous system  

MedlinePLUS

The central nervous system is composed of the brain and spinal cord. Your brain and spinal cord serve as the main "processing center" for the entire nervous system, and control all the workings of your body.

449

Information Materials Adaptive Systems.  

National Technical Information Service (NTIS)

The report includes the realization of adaptive control algorithms, elements of adaptive control systems, self-adjusting control systems for an aeroelastic aircraft, adaptive control of flight vehicle roll, flight vehicle control during atmospheric reentr...

1972-01-01

450

Intra-Spin System  

Center for Biologics Evaluation and Research (CBER)

... Intra-Spin System. Applicant: Intra-Lock International, Boca Raton, FL 33487. 510(k) number: BK120048. Product: Intra-Spin System. ... More results from www.fda.gov/biologicsbloodvaccines/bloodbloodproducts/approvedproducts

451

Urban Information System.  

National Technical Information Service (NTIS)

The development and operation of a computer-based human services information system in Chattanooga, Tennessee are documented in a technically oriented report. The Chattanooga Human Services Information System is designed to provide direct service agencies...

1973-01-01

452

Absorption heat pump system  

DOEpatents

The efficiency of an absorption heat pump system is improved by conducting liquid from a second stage evaporator thereof to an auxiliary heat exchanger positioned downstream of a primary heat exchanger in the desorber of the system.

Grossman, G.

1982-06-16

453

Absorption heat pump system  

DOEpatents

The efficiency of an absorption heat pump system is improved by conducting liquid from a second stage evaporator thereof to an auxiliary heat exchanger positioned downstream of a primary heat exchanger in the desorber of the system.

Grossman, Gershon (Oak Ridge, TN)

1984-01-01

454

Secondary power systems  

SciTech Connect

In aeronautical engineering secondary power systems have long played second fiddle to the airframe, the engine, and indeed, the avionics. This collection of papers is thus timely, and its publication by the Institution of Mechanical Engineers appropriate, as secondary power systems in modern aircraft present challenging mechanical engineering problems. In military aircraft demands for electrical and hydraulic power and high pressure air have grown over the past two decades. To these basic needs are added requirements for emergency power, ground power, and independent engine starting. Additionally increased reliability and maintainability is demanded from all secondary power systems. Complete contents: What is a secondary power system. Modern technology secondary power systems for next generation military aircraft; Integrated power units; Secondary power system gearbox; Starting the system - air turbine starters; Auxiliary and emergency power system; Secondary hydraulic power generation; Advanced technology electrical power generation equipment.

Not Available

1985-01-01

455

Recoil and Equilibrator Systems.  

National Technical Information Service (NTIS)

The pamphlet provides a general guide for the testing of recoil and equilibrator systems. Described are the arrival, prefiring, firing, post-firing and road tests to which the hydropneumatic and hydrospring recoil systems, and pneumatic, hydropneumatic an...

1966-01-01

456

Secure Distributed File Systems.  

National Technical Information Service (NTIS)

Secure information distribution is a strategic capability as significant as weapons systems and tactics to military operations. The Department of Defense has recognized the importance of establishing and maintaining secure distributed file systems and exp...

T. M. Conroy W. H. Buxton

1994-01-01

457

Decision Support Systems: Theory.  

National Technical Information Service (NTIS)

The purpose of this project was to research, collect, and evaluate all available information on Decision Support Systems (DSS) Theory. DSS are interactive, conversational computer systems supporting decision makers. DSS rely heavily on human intuition, ju...

J. J. Jarvis

1976-01-01

458

All Systems Are Go  

NSDL National Science Digital Library

Test your knowledge of the digestive, respiratory, and other human body systems in this interactive game from Kinetic City. Race the clock to put Arnold's organs back into his body one system at a time.

Foundation, Wgbh E.

2007-08-09

459

Systems engineering management plan  

SciTech Connect

The purpose of this Systems Engineering Management Plan (SEMP) is to prescribe the systems engineering procedures to be implemented at the Program level and the minimum requirements for systems engineering at the Program-element level. The Program level corresponds to the Director, OCRWM, or to the organizations within OCRWM to which the Director delegates responsibility for the development of the System and for coordinating and integrating the activities at the Program-element level. The Office of Policy and Outreach (OPO) and the Office of Resource Management (ORM) support the Director at the Program level. The Program-element level corresponds to the organizations within OCRWM (i.e., the Office of Geologic Repositories (OGR) and the Office of Storage and Transportation Systems (OSTS)) with overall responsibility for developing the System elements - that is, the mined geologic disposal system (MGDS), monitored retrievable storage (MRS) (if approved by Congress), and the transportation system.

Conner, C.W.

1985-10-01

460

Inflatable Aeroponic System.  

National Technical Information Service (NTIS)

Aeroponics Internationals (AI) innovation is a self-contained, self-supporting, flexible low mass aeroponic crop production unit with integral environmental systems for the control and delivery of a nutrient mist to the roots. This FLEX Aeroponic System m...

J. V. Pelt

2005-01-01

461

Health System Measurement Project  

MedlinePLUS

... U.S. Department of Health & Human Services Health System Measurement Project Search string Home Topical Areas Measures Data ... Sign out About the Project The Health System Measurement Project tracks government data on critical U.S. health ...

462

Systems Acquisition Strategies.  

National Technical Information Service (NTIS)

Notwithstanding determined efforts during the 1960s to improve major system acquisitions, the typical program exhibited an average cost growth of about 40%, a schedule slip of about 15%, and 30% or 40% system performance deviation from original specificat...

A. J. Harman G. K. Smith R. Perry S. Henrichsen

1971-01-01

463

Intelligent dynamic systems  

Microsoft Academic Search

This paper concerns a new class of systems that are, on the one hand, dynamic systems, and on the other, intelligent systems,\\u000a as their dynamics is described by knowledge representation, which is a common practice to use in intelligent systems, and\\u000a the states are described by parameters and variables that have a logical or linguistic character. The case is considered

G. S. Osipov

2010-01-01

464

Introducing Systems Approaches  

Microsoft Academic Search

\\u000a Systems Approaches to Managing Change brings together five systems approaches to managing complex issues, each having a proven\\u000a track record of over 25 years. The five approaches are: System Dynamics (SD) developed originally in the late 1950s by Jay\\u000a Forrester Viable Systems Model (VSM) developed originally in the late 1960s by Stafford Beer Strategic Options Development\\u000a and Analysis (SODA: with

Martin Reynolds; Sue Holwell

2010-01-01

465

Systems of Equations  

NSDL National Science Digital Library

This project is to help you practice solving systems of equations! Begin by playing a game of Jeopardy. This is for 2 players. You can select easy or hard problems for different point values. USE SCRATCH PAPER! Systems Jeopardy! Next, play some systems basketball. This is also for 2 players and again, you will need to USE SCRATCH PAPER! Systems Hoop Shoot These next 2 links are ...

Hbinggeli

2011-01-06

466

Modular integrated video system  

SciTech Connect

The Modular Integrated Video System (MIVS) is intended to provide a simple, highly reliable closed circuit television (CCTV) system capable of replacing the IAEA Twin Minolta Film Camera Systems in those safeguards facilities where mains power is readily available, and situations where it is desired to have the CCTV camera separated from the CCTV recording console. This paper describes the MIVS and the Program Plan which is presently being followed for the development, testing, and implementation of the system.

Gaertner, K.J.; Heaysman, B.; Holt, R.; Sonnier, C.

1986-01-01

467

Visual Alert System  

NASA Astrophysics Data System (ADS)

A visual alert system resulted from circuitry developed by Applied Cybernetics Systems for Langley as part of a space related telemetry system. James Campman, Applied Cybernetics president, left the company and founded Grace Industries, Inc. to manufacture security devices based on the Langley technology. His visual alert system combines visual and audible alerts for hearing impaired people. The company also manufactures an arson detection device called the electronic nose, and is currently researching additional applications of the NASA technology.

1985-01-01

468

Our Solar System  

NSDL National Science Digital Library

Name and describe each of the planets, including the sun, in our solar system. 1. Use the organizer provided to record the information you collect. Click Solar System Organizer. 2. Now watch a short video about our solar system. As you watch the video, begin writing information you learn about the planets on your organizer. Click Solar System 101 for the video. 3. Next, watch the video with the ...

Tbeauchamp

2012-04-09

469

Versados (operating system)  

SciTech Connect

Versados is a multitasking operation system designed to meet the requirements of the real-time, online control system environment as well as to support the multiuser software-hardware engineering effort required to develop microprocessor based systems. Versados serves as a major software building block for real-time applications which use the Motorola MC68000 microprocessor and Versamodule board products. It is a modular, multilayered operating system.

Glaser, J.G.

1981-01-01

470

Generalized Stäckel systems  

NASA Astrophysics Data System (ADS)

We consider the generalized Stäckel systems, the broadest class of integrable Hamiltonian systems that admit separation of variables and possess separation relations affine in the Hamiltonians. For these systems we construct in a systematic fashion hierarchies of basic separable potentials. Moreover, we show how the equations of motion for the systems under study are related through appropriately chosen reciprocal transformations and how the respective constants of motion are related through generalized Stäckel transforms.

B?aszak, Maciej; Sergyeyev, Artur

2011-07-01

471

Indistinguishability of Random Systems  

Microsoft Academic Search

An (X;Y)-random system takes inputs X1;X2;:::2X and generates, for each new input Xi, an output Yi 2 Y, depending proba- bilistically on X1;:::;Xi and Y1;:::;Yi¡1. Many cryptographic systems like block ciphers, MAC-schemes, pseudo-random functions, etc., can be modeled as random systems, where in fact Yi often depends only on Xi, i.e., the system is stateless. The security proof of such

Ueli M. Maurer

2002-01-01

472

Systems with Lebesgue Sampling  

Microsoft Academic Search

Sampling is normally done periodically in time. For linear time invariant systems this leads to closed loop systems that linear\\u000a and periodic. Many properties can be investigated by considering the behavior of the systems at times that are synchronized\\u000a with the sampling instants. This leads to drastic simplifications because the systems can be described by difference equations\\u000a with constant coefficients.

Karl Åström; Bo Bernhardsson

473

Anidolic daylighting systems  

Microsoft Academic Search

Non-imaging optics, well known for its application to solar concentrators, was used to set up novel daylighting systems that aim at an efficient collection and redistribution of the diffuse component of daylight. These devices, called anidolic systems (an: without, eidolon: image), were designed, installed and monitored on experimental test modules under clear and overcast sky conditions. Three different anidolic systems

Jean-Louis Scartezzini; Gilles Courret

2002-01-01

474

Lincoln Training System.  

National Technical Information Service (NTIS)

LTS (Lincoln Training System) is an automated training system that has been designed to meet the need for individualized, self-paced learning outside of as well as within a conventional classroom environment. The system employs microfiche as the basic med...

D. Karp F. C. Frick J. R. Brown L. M. Goodman W. P. Harris

1973-01-01

475

Inductive System Health Monitoring  

Microsoft Academic Search

The Inductive Monitoring System (IMS) software was developed to provide a technique to automatically produce health monitoring knowledge bases for systems that are either difficult to model (simulate) with a computer or which require computer models that are too complex to use for real time monitoring. IMS uses nominal data sets collected either directly from the system or from simulations

David L. Iverson

2004-01-01

476

Clinical Data Management System  

Microsoft Academic Search

Reference clinical data interchange standards defined by CDISC (Clinical Data Interchange Standards Consortium), we developed clinical data management system with distributed system architecture which can be executed on different platforms for high performance. This system consists mainly of study management module, data capture module, data management module and security module. Besides, web-based approach changes the traditional client\\/server design pattern for

Lingli Fu; Sheng Ding; Tao Chen

2010-01-01

477

Mars transportation system synthesis  

Microsoft Academic Search

Performance and requirements synthesized to support the manned Mars mission of the Space Exploration Initiative (SEI) are presented. Emphasis is placed on the Mars transportation system (MTS), which uses nuclear thermal rocket (NTR) propulsion technology associated with accomplishing the manned Mars mission. Data are also presented for a propulsion system options comparison of chemical\\/aerobrake and nuclear electric propulsion systems. Vehicle-

Archie C. Young; John A. Mulqueen; William J. Emrich

1992-01-01

478

Training Management Information System  

Microsoft Academic Search

The Training Management Information System (TMIS) is an integrated information system for all training related activities. TMIS is at the leading edge of training information systems used in the nuclear industry. The database contains all the necessary records to confirm the department's adherence to accreditation criteria and houses all test questions, student records and information needed to evaluate the training

Rackley

1989-01-01

479

Ocean engineering power systems  

Microsoft Academic Search

The text presents basic thermodynamic principles and engineering considerations for ocean power systems. A survey chapter introduces a wide range of applications of power systems in the oceans. Thermodynamic principles and engine cycles are extensively reviewed in the next chapter. Then, chapters on energy sources, thermal power plants, and engineering of specific types of ocean systems are presented. Engineering principles

Carmichael

1974-01-01

480

Dynamics of Multibody Systems  

Microsoft Academic Search

Dynamics of Multibody Systems introduces multibody dynamics, with an emphasis on flexible body dynamics. Many common mechanisms such as automobiles, space structures, robots, and micro machines have mechanical and structural systems that consist of interconnected rigid and deformable components. The dynamics of these large-scale, multibody systems are highly nonlinear, presenting complex problems that in most cases can only be solved

Ahmed A. Shabana

2005-01-01

481

Digital Synchronous Control System.  

National Technical Information Service (NTIS)

A digital synchronous follow-up system is described, which can be used in high-precision rate stabilization systems. The system consists of two angle-pulse transducers (APT), logic module, which functions as a specialized computing and compensating device...

V. N. Govorun V. I. In'shakov A. P. Leonov V. V. Popov V. V. Skvortsov

1983-01-01

482

Acoustic Accident Detection System  

Microsoft Academic Search

In this research we considered the development of a system for automatically detecting and reporting traffic accidents at intersections. A system with these properties would be a great benefit in determining the cause of accidents and could also be useful in determining features of the intersection that relate to safety. A complete system would automatically detect and record traffic conditions

Charles Harlow; Yu Wang

2002-01-01

483

Power system restoration issues  

Microsoft Academic Search

Some of the problems encountered in the three phases of power system restoration (PSR) are described. The three phases are planning for restart and reintegration of the bulk power supply, actions during system degradations for saving and retaining critical sources of power, and restoration when the power system has stabilized at some degraded level. Common concerns found in several PSR

M. M. Adibi; R. J. Kafka

1991-01-01

484

NPOx Decontamination System  

SciTech Connect

The nitric acid/potassium permanganate/oxalic acid (NPOx) Phase II system is being prepared for remote operation at the Idaho National Engineering and Environmental Laboratory (INEEL). Several tests have been conducted to prepare the system for remote operation. This system performs very well with high decontamination efficiencies and very low quantities of waste generated during decontamination.

Archibald, K.; Demmer, R.; Argyle, M.; Ancho, M.; Hai-Pao, J.

2002-02-25

485

Evaluating Recommender Systems  

Microsoft Academic Search

Recommender systems are considered as an answer to the information overload in a Web environment. Such systems recommend items (movies, music, books, news, web pages, etc.) that the user should be interested in. Collaborative filtering recommender systems have a huge success in commercial applications. The sales in these applications follow a power law distribution. However, with the increase of the

Zied Zaier; Robert Godin; Luc Faucher

2008-01-01

486

FUNDAMENTALS OF TELEVISION SYSTEMS.  

ERIC Educational Resources Information Center

DESIGNED FOR A READER WITHOUT SPECIAL TECHNICAL KNOWLEDGE, THIS ILLUSTRATED RESOURCE PAPER EXPLAINS THE COMPONENTS OF A TELEVISION SYSTEM AND RELATES THEM TO THE COMPLETE SYSTEM. SUBJECTS DISCUSSED ARE THE FOLLOWING--STUDIO ORGANIZATION AND COMPATIBLE COLOR TELEVISION PRINCIPLES, WIRED AND RADIO TRANSMISSION SYSTEMS, DIRECT VIEW AND PROJECTION…

KESSLER, WILLIAM J.

487

Solar systems maintenance  

SciTech Connect

This article examines several hundred solar systems, especially those in the HUD Solar Residential Demonstration Program, in order to show that solar energy systems have all the maintenance requirements of non-solar HVAC systems, as well as additional ones peculiar to solar systems. The additional maintenance requirements occur because of the special features in solar systems, such as the collector panels, the conditions to which the heat-transfer fluid can be subjected, and the special corrosion problems. It is concluded that the simplest systems are the easiest to maintain; regular inspection and maintenance of a solar system can help prevent major expenses for repair and replacement; the ease of maintenance should be a factor considered during design and installation of a solar system; it is important to include adequate measuring instruments in a solar system, especially thermometers, flowmeters, and pressure gages; in liquid-based solar systems, the major cause of problems is corrosion which requires special attention; in air solar systems, the main problem is air leakage, which is not easily detected directly and generally shows itself in terms of poor performance; and site-built and site-assembled solar collectors are generally high-maintenance parts of a solar system and should be inspected regularly.

Dubin, F.S.; Raman, K.

1983-12-01

488

Rapid response deluge system  

NASA Astrophysics Data System (ADS)

The development of a rapid response deluge system by the Ammunition Equipment Directorate (AED) for use in suppressing propellant fires during demilitarization shows great promise. Prototype systems have been tested and data acquired on their efficiencies. Present system vs previous generations and lessons learned are discussed.

Mille, J. R.

1984-08-01

489

Fuzzy systems vegetation theory  

Microsoft Academic Search

Fuzzy systems vegetation theory is a comprehensive framework for the expression of vegetation theory and conceptual models, as well as the development of vegetation analyses. It is applicable to vegetation\\/environment relations, vegetation dynamics, and the effects of environmental dynamics on vegetation composition. Fuzzy systems vegetation theory is a fuzzy set generalization of dynamical systems theory and incorporates a formal logic

David W. Roberts

1989-01-01

490

Instructional System Development.  

ERIC Educational Resources Information Center

The manual presents a technology of instructional design and a model for developing and conducting efficient and cost effective Air Force instructional systems. Chapter 1 provides an overview of Instructional System Development (ISD). Chapters 2-6 each focus on a step of the process: analysis of system requirements; definition of…

Department of the Air Force, Washington, DC.

491

Unified Science - System.  

ERIC Educational Resources Information Center

The goals of this curriculum, developed as a summer course for the Young Scholars Program at The Ohio State University-Columbus, are as follows: (1) enable students to develop an understanding of the concept of a system; (2) help students gain an appreciation of the value of systems; (3) develop skills in working with systems; (4) expand skills in…

Thomson, Barbara S.

492

Classification of agroforestry systems  

Microsoft Academic Search

Classification of agroforestry (AF) systems is necessary in order to provide a framework for evaluating systems and developing action plans for their improvement. The AF Systems Inventory (AFSI) being undertaken by ICRAF provides the background information for an approach to classification.

P. K. R. Nair

1985-01-01

493

Wabtec ECP system update  

Microsoft Academic Search

Wabtec Railway Electronics installed an electronically controlled pneumatic (ECP) brake system on Southern Company owned coal cars, operated on CSX, with GE AC4400 locomotives in November, 2000. This is the first US installation of ECP systems in accordance with AAR S-4200 series of specifications, which also uses the echelon PLT-22 power line transceiver. The ECP system as installed is described,

R. C. Kull

2001-01-01

494

Distributed computer control systems  

Microsoft Academic Search

This book focuses on recent advances in the theory, applications and techniques for distributed computer control systems. Contents (partial): Real-time distributed computer control in a flexible manufacturing system. Semantics and implementation problems of channels in a DCCS specification. Broadcast protocols in distributed computer control systems. Design considerations of distributed control architecture for a thermal power plant. The conic toolset for

Suski

1986-01-01

495

Engineering Secure Software Systems  

Microsoft Academic Search

Is there such a thing anymore as a software system that doesn't need to be secure? Almost every software- controlled system faces threats from potential adversaries, from Internet-aware client applications running on PCs, to complex telecommunications and power systems accessible over the Internet, to commodity software with copy protec- tion mechanisms. Software engineers must be cognizant of these threats and

Premkumar T. Devanbu; Stuart G. Stubblebine

496

Egyptian Caste System  

NSDL National Science Digital Library

Understand the culture, character, and societal characteristics of different classes in the ancient Egyptian caste system Understand the culture, character, and societal characteristics of different classes in the ancient Egyptian caste system Go to these sites to learn about the Egyptian Caste System ...

Issen, Ms.

2009-09-17

497

Systemic Change in Education.  

ERIC Educational Resources Information Center

|This book provides new tools for thinking about and designing the education system. Four sections, each with its own introduction, follow Charles M. Reigeluth's introductory chapter, "Introduction: The Imperative for Systemic Change." Section 1 describes some theoretical frameworks for understanding the "big ideas" of system design. It includes:…

Reigeluth, Charles M., Ed.; Garfinkle, Robert J., Ed.

498

Fertilizers in agroforestry systems  

Microsoft Academic Search

This review encompasses results of fertilization experiments on several agroforestry systems—alley cropping, perennial shade systems, home gardens—in which fertilizer use is a likely management alternative. Fertilizer response was found to be most common in alley cropping, variable in perennial shade systems, and rarely reported in home gardens. Level of nutrient removal in harvested products is probably the overriding factor in

L. T. Szott; D. C. L. Kass

1993-01-01

499

Automated Legislative Information Systems  

Microsoft Academic Search

Over the past fifty years the American legal system has changed from a system dominated by case law to a system dominated by legislation. The expanding role that legislation has assumed is apparent, not only by the scholarly commentary precipitated by this change, but also by the new legislative research tools which have become commonplace in many law libraries. Well-established

S Blair Kauffman

1983-01-01

500

Carbon Dioxide Reduction System.  

National Technical Information Service (NTIS)

An automatically operated carbon dioxide reduction system was developed, fabricated and tested. The system was designed to reduce the carbon dioxide equivalent to that produced by one man, and to produce carbon and oxygen. A system such as this is require...

H. Chandler

1964-01-01