Cawley, William E.; Warnick, Robert F.
1982-01-01
1. In a nuclear reactor incorporating a plurality of columns of tubular fuel elements disposed in horizontal tubes in a mass of graphite wherein water flows through the tubes to cool the fuel elements, the improvement comprising at least one control column disposed in a horizontal tube including fewer fuel elements than in a normal column of fuel elements and tubular control elements disposed at both ends of said control column, and means for varying the horizontal displacement of the control column comprising a winch at the upstream end of the control column and a cable extending through the fuel and control elements and attached to the element at the downstream end of the column.
Active control of multi-element rotor blade airfoils
NASA Technical Reports Server (NTRS)
Torok, Michael S. (Inventor); Moffitt, Robert C. (Inventor); Bagai, Ashish (Inventor)
2005-01-01
A multi-element rotor blade includes an individually controllable main element and fixed aerodynamic surface in an aerodynamically efficient location relative to the main element. The main element is controlled to locate the fixed aerodynamic surface in a position to increase lift and/or reduce drag upon the main element at various azimuthal positions during rotation.
Quick release latch for reactor scram
Johnson, Melvin L.; Shawver, Bruce M.
1976-01-01
A simple, reliable, and fast-acting means for releasing a control element and allowing it to be inserted rapidly into the core region of a nuclear reactor for scram purposes. A latch mechanism grips a coupling head on a nuclear control element to connect the control element to the control drive assembly. The latch mechanism is closed by tensioning a cable or rod with an actuator. The control element is released by de-energizing the actuator, providing fail-safe, rapid release of the control element to effect reactor shutdown. A sensing rod provides indication that the control element is properly positioned in the latch. Two embodiments are illustrated, one involving a collet-type latch mechanism, the other a pliers-type latch mechanism with the actuator located inside the reactor vessel.
Quick release latch for reactor scram
Johnson, M.L.; Shawver, B.M.
1975-09-16
A simple, reliable, and fast-acting means for releasing a control element and allowing it to be inserted rapidly into the core region of a nuclear reactor for scram purposes is described. A latch mechanism grips a coupling head on a nuclear control element to connect the control element to the control drive assembly. The latch mechanism is closed by tensioning a cable or rod with an actuator. The control element is released by de-energizing the actuator, providing fail-safe, rapid release of the control element to effect reactor shutdown. A sensing rod provides indication that the control element is properly positioned in the latch. Two embodiments are illustrated, one involving a collet- type latch mechanism, the other a pliers-type latch mechanism with the actuator located inside the reactor vessel. (auth)
NASA Technical Reports Server (NTRS)
Dingell, Charles W. (Inventor); Quintana, Clemente E. (Inventor); Le, Suy (Inventor); Clark, Michael R. (Inventor); Cloutier, Robert E. (Inventor); Hafermalz, David Scott (Inventor)
2009-01-01
A sublimator includes a sublimation plate having a thermal element disposed adjacent to a feed water channel and a control point disposed between at least a portion of the thermal element and a large pore substrate. The control point includes a sintered metal material. A method of dissipating heat using a sublimator includes a sublimation plate having a thermal element and a control point. The thermal element is disposed adjacent to a feed water channel and the control point is disposed between at least a portion of the thermal element and a large pore substrate. The method includes controlling a flow rate of feed water to the large pore substrate at the control point and supplying heated coolant to the thermal element. Sublimation occurs in the large pore substrate and the controlling of the flow rate of feed water is independent of time. A sublimator includes a sublimation plate having a thermal element disposed adjacent to a feed water channel and a control point disposed between at least a portion of the thermal element and a large pore substrate. The control point restricts a flow rate of feed water from the feed water channel to the large pore substrate independent of time.
NEUTRONIC REACTOR CONTROL ELEMENT
Newson, H.W.
1960-09-13
A novel composite neutronic reactor control element is offered. The element comprises a multiplicity of sections arranged in end-to-end relationship, each of the sections having a markedly different neutron-reactive characteristic. For example, a three-section control element could contain absorber, moderator, and fuel sections. By moving such an element longitudinally through a reactor core, reactivity is decreased by the absorber, increased slightly by the moderator, or increased substantially by the fuel. Thus, control over a wide reactivity range is provided.
Kaufman, H.B.; Weiss, A.A.
1959-08-18
A shadow control device for controlling a nuclear reactor is described. The device comprises a series of hollow neutron-absorbing elements arranged in groups, each element having a cavity for substantially housing an adjoining element and a longitudinal member for commonly supporting the groups of elements. Longitudinal actuation of the longitudinal member distributes the elements along its entire length in which position maximum worth is achieved.
Effects of controlled element dynamics on human feedforward behavior in ramp-tracking tasks.
Laurense, Vincent A; Pool, Daan M; Damveld, Herman J; van Paassen, Marinus René M; Mulder, Max
2015-02-01
In real-life manual control tasks, human controllers are often required to follow a visible and predictable reference signal, enabling them to use feedforward control actions in conjunction with feedback actions that compensate for errors. Little is known about human control behavior in these situations. This paper investigates how humans adapt their feedforward control dynamics to the controlled element dynamics in a combined ramp-tracking and disturbance-rejection task. A human-in-the-loop experiment is performed with a pursuit display and vehicle-like controlled elements, ranging from a single integrator through second-order systems with a break frequency at either 3, 2, or 1 rad/s, to a double integrator. Because the potential benefits of feedforward control increase with steeper ramp segments in the target signal, three steepness levels are tested to investigate their possible effect on feedforward control with the various controlled elements. Analyses with four novel models of the operator, fitted to time-domain data, reveal feedforward control for all tested controlled elements and both (nonzero) tested levels of ramp steepness. For the range of controlled element dynamics investigated, it is found that humans adapt to these dynamics in their feedforward response, with a close to perfect inversion of the controlled element dynamics. No significant effects of ramp steepness on the feedforward model parameters are found.
NASA Technical Reports Server (NTRS)
Rajiyah, Harindra (Inventor); Hedeen, Robert A. (Inventor); Pla, Frederic G. (Inventor); Renshaw, Anthony A. (Inventor)
1995-01-01
A noise source for an aircraft engine active noise cancellation system in which the resonant frequency of a noise radiating element is tuned to permit noise cancellation over a wide range of frequencies. The resonant frequency of the noise radiating element is tuned by a plurality of force transmitting mechanisms which contact the noise radiating element. Each one of the force transmitting mechanisms includes an expandable element and a spring in contact with the noise radiating element so that excitation of the element varies the spring force applied to the noise radiating element. The elements are actuated by a controller which receives input of a signal proportional to displacement of the noise radiating element and a signal corresponding to the blade passage frequency of the engine's fan. In response, the controller determines a control signal which is sent to the elements and causes the spring force applied to the noise radiating element to be varied. The force transmitting mechanisms can be arranged to either produce bending or linear stiffness variations in the noise radiating element.
High-temperature brushless DC motor controller
Cieslewski, Crzegorz; Lindblom, Scott C.; Maldonado, Frank J.; Eckert, Michael Nathan
2017-05-16
A motor control system for deployment in high temperature environments includes a controller; a first half-bridge circuit that includes a first high-side switching element and a first low-side switching element; a second half-bridge circuit that includes a second high-side switching element and a second low-side switching element; and a third half-bridge circuit that includes a third high-side switching element and a third; low-side switching element. The motor controller is arranged to apply a pulse width modulation (PWM) scheme to switch the first half-bridge circuit, second half-bridge circuit, and third half-bridge circuit to power a motor.
Phased-Array Antenna With Optoelectronic Control Circuits
NASA Technical Reports Server (NTRS)
Kunath, Richard R.; Shalkhauser, Kurt A.; Martzaklis, Konstantinos; Lee, Richard Q.; Downey, Alan N.; Simons, Rainee N.
1995-01-01
Prototype phased-array antenna features control of amplitude and phase at each radiating element. Amplitude- and phase-control signals transmitted on optical fiber to optoelectronic interface circuit (OEIC), then to monolithic microwave integrated circuit (MMIC) at each element. Offers advantages of flexible, rapid electronic steering and shaping of beams. Furthermore, greater number of elements, less overall performance of antenna degraded by malfunction in single element.
Multichannel optical sensing device
Selkowitz, S.E.
1985-08-16
A multichannel optical sensing device is disclosed, for measuring the outdoor sky luminance or illuminance or the luminance or illuminance distribution in a room, comprising a plurality of light receptors, an optical shutter matrix including a plurality of liquid crystal optical shutter elements operable by electrical control signals between light transmitting and light stopping conditions, fiber optical elements connected between the receptors and the shutter elements, a microprocessor based programmable control unit for selectively supplying control signals to the optical shutter elements in a programmable sequence, a photodetector including an optical integrating spherical chamber having an input port for receiving the light from the shutter matrix and at least one detector element in the spherical chamber for producing output signals corresponding to the light, and output units for utilizing the output signals including a storage unit having a control connection to the microprocessor based programmable control unit for storing the output signals under the sequence control of the programmable control unit.
Multichannel optical sensing device
Selkowitz, Stephen E.
1990-01-01
A multichannel optical sensing device is disclosed, for measuring the outr sky luminance or illuminance or the luminance or illuminance distribution in a room, comprising a plurality of light receptors, an optical shutter matrix including a plurality of liquid crystal optical shutter elements operable by electrical control signals between light transmitting and light stopping conditions, fiber optic elements connected between the receptors and the shutter elements, a microprocessor based programmable control unit for selectively supplying control signals to the optical shutter elements in a programmable sequence, a photodetector including an optical integrating spherical chamber having an input port for receiving the light from the shutter matrix and at least one detector element in the spherical chamber for producing output signals corresponding to the light, and output units for utilizing the output signals including a storage unit having a control connection to the microprocessor based programmable control unit for storing the output signals under the sequence control of the programmable control unit.
Fuel control for gas turbine engines
DOE Office of Scientific and Technical Information (OSTI.GOV)
Stearns, C.F.; Tutherly, H.W.
1983-12-27
The basic gas turbine engine hydromechanical fuel control is adaptable to different engine configurations such as turbofan, turboprop and turboshaft engines by incorporating in the main housing those elements having a commonality to all engine configurations and providing a removable block for each configuration having the necessary control elements and flow passages required for that particular configuration. That is to say, a block with the elements peculiar to a turbofan engine could be replaced by a mating block that includes those elements peculiar to a turboshaft engine in adapting the control for a turboshaft configuration. Similarly another block with thosemore » elements peculiar to a turboprop engine could replace any of the other blocks in adapting the control to a turboprop configuration. Obviously the basic control has the necessary flow passages terminating at the interface with the block and these flow passages mate with corresponding passages in the block.« less
Dubay, Rickey; Hassan, Marwan; Li, Chunying; Charest, Meaghan
2014-09-01
This paper presents a unique approach for active vibration control of a one-link flexible manipulator. The method combines a finite element model of the manipulator and an advanced model predictive controller to suppress vibration at its tip. This hybrid methodology improves significantly over the standard application of a predictive controller for vibration control. The finite element model used in place of standard modelling in the control algorithm provides a more accurate prediction of dynamic behavior, resulting in enhanced control. Closed loop control experiments were performed using the flexible manipulator, instrumented with strain gauges and piezoelectric actuators. In all instances, experimental and simulation results demonstrate that the finite element based predictive controller provides improved active vibration suppression in comparison with using a standard predictive control strategy. Copyright © 2014 ISA. Published by Elsevier Ltd. All rights reserved.
Thermoelectric refrigerator having improved temperature stabilization means
Falco, Charles M.
1982-01-01
A control system for thermoelectric refrigerators is disclosed. The thermoelectric refrigerator includes at least one thermoelectric element that undergoes a first order change at a predetermined critical temperature. The element functions as a thermoelectric refrigerator element above the critical temperature, but discontinuously ceases to function as a thermoelectric refrigerator element below the critical temperature. One example of such an arrangement includes thermoelectric refrigerator elements which are superconductors. The transition temperature of one of the superconductor elements is selected as the temperature control point of the refrigerator. When the refrigerator attempts to cool below the point, the metals become superconductors losing their ability to perform as a thermoelectric refrigerator. An extremely accurate, first-order control is realized.
42 CFR 431.810 - Basic elements of the Medicaid eligibility quality control (MEQC) program.
Code of Federal Regulations, 2011 CFR
2011-10-01
... 42 Public Health 4 2011-10-01 2011-10-01 false Basic elements of the Medicaid eligibility quality control (MEQC) program. 431.810 Section 431.810 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES... elements of the Medicaid eligibility quality control (MEQC) program. (a) General requirements. The agency...
Actively controlled vibration welding system and method
Cai, Wayne W.; Kang, Bongsu; Tan, Chin-An
2013-04-02
A vibration welding system includes a controller, welding horn, an active material element, and anvil assembly. The assembly may include an anvil body connected to a back plate and support member. The element, e.g., a piezoelectric stack or shape memory alloy, is positioned with respect to the assembly. The horn vibrates in a desirable first direction to form a weld on a work piece. The element controls any vibrations in a second direction by applying calibrated response to the anvil body in the second direction. A method for controlling undesirable vibrations in the system includes positioning the element with respect to the anvil assembly, connecting the anvil body to the support member through the back plate, vibrating the horn in a desirable first direction, and transmitting an input signal to the element to control vibration in an undesirable second direction.
Architecture for reactive planning of robot actions
NASA Astrophysics Data System (ADS)
Riekki, Jukka P.; Roening, Juha
1995-01-01
In this article, a reactive system for planning robot actions is described. The described hierarchical control system architecture consists of planning-executing-monitoring-modelling elements (PEMM elements). A PEMM element is a goal-oriented, combined processing and data element. It includes a planner, an executor, a monitor, a modeler, and a local model. The elements form a tree-like structure. An element receives tasks from its ancestor and sends subtasks to its descendants. The model knowledge is distributed into the local models, which are connected to each other. The elements can be synchronized. The PEMM architecture is strictly hierarchical. It integrated planning, sensing, and modelling into a single framework. A PEMM-based control system is reactive, as it can cope with asynchronous events and operate under time constraints. The control system is intended to be used primarily to control mobile robots and robot manipulators in dynamic and partially unknown environments. It is suitable especially for applications consisting of physically separated devices and computing resources.
Finite Element Analysis of Adaptive-Stiffening and Shape-Control SMA Hybrid Composites
NASA Technical Reports Server (NTRS)
Gao, Xiujie; Burton, Deborah; Turner, Travis L.; Brinson, Catherine
2005-01-01
Shape memory alloy hybrid composites with adaptive-stiffening or morphing functions are simulated using finite element analysis. The composite structure is a laminated fiber-polymer composite beam with embedded SMA ribbons at various positions with respect to the neutral axis of the beam. Adaptive stiffening or morphing is activated via selective resistance heating of the SMA ribbons or uniform thermal loads on the beam. The thermomechanical behavior of these composites was simulated in ABAQUS using user-defined SMA elements. The examples demonstrate the usefulness of the methods for the design and simulation of SMA hybrid composites. Keywords: shape memory alloys, Nitinol, ABAQUS, finite element analysis, post-buckling control, shape control, deflection control, adaptive stiffening, morphing, constitutive modeling, user element
Development of an hp-version finite element method for computational optimal control
NASA Technical Reports Server (NTRS)
Hodges, Dewey H.; Warner, Michael S.
1993-01-01
The purpose of this research effort is to develop a means to use, and to ultimately implement, hp-version finite elements in the numerical solution of optimal control problems. The hybrid MACSYMA/FORTRAN code GENCODE was developed which utilized h-version finite elements to successfully approximate solutions to a wide class of optimal control problems. In that code the means for improvement of the solution was the refinement of the time-discretization mesh. With the extension to hp-version finite elements, the degrees of freedom include both nodal values and extra interior values associated with the unknown states, co-states, and controls, the number of which depends on the order of the shape functions in each element.
Transposable Elements and Genetic Instabilities in Crop Plants
DOE R&D Accomplishments Database
Burr, B.; Burr, F.
1981-04-10
Transposable elements have long been associated with certain unstable loci in maize and have been intensively studied by McClintock and others. It is known that a transposable element can control the expression of the structural genes at the locus where it resides. These controlling elements in maize are now beginning to be studied at the molecular level. Using recombinant molecular probes we have been able to describe the changes induced by the controlling element Ds at the shrunken locus. Ds elements appear to be large and dissimilar insertions into the wild-type locus - two elements actually map within the transcribed region of the gene. Genetic instabilities have been described in other economically important plants but the bases for these phenomena have not been understood. We believe that it is likely that some of these instabilities are the result of transposable element activity much as in the case of maize.
Development of an hp-version finite element method for computational optimal control
NASA Technical Reports Server (NTRS)
Hodges, Dewey H.; Warner, Michael S.
1993-01-01
The purpose of this research effort was to begin the study of the application of hp-version finite elements to the numerical solution of optimal control problems. Under NAG-939, the hybrid MACSYMA/FORTRAN code GENCODE was developed which utilized h-version finite elements to successfully approximate solutions to a wide class of optimal control problems. In that code the means for improvement of the solution was the refinement of the time-discretization mesh. With the extension to hp-version finite elements, the degrees of freedom include both nodal values and extra interior values associated with the unknown states, co-states, and controls, the number of which depends on the order of the shape functions in each element. One possible drawback is the increased computational effort within each element required in implementing hp-version finite elements. We are trying to determine whether this computational effort is sufficiently offset by the reduction in the number of time elements used and improved Newton-Raphson convergence so as to be useful in solving optimal control problems in real time. Because certain of the element interior unknowns can be eliminated at the element level by solving a small set of nonlinear algebraic equations in which the nodal values are taken as given, the scheme may turn out to be especially powerful in a parallel computing environment. A different processor could be assigned to each element. The number of processors, strictly speaking, is not required to be any larger than the number of sub-regions which are free of discontinuities of any kind.
Mobile monolithic polymer elements for flow control in microfluidic devices
Hasselbrink, Jr., Ernest F.; Rehm, Jason E.; Shepodd, Timothy J.
2004-08-31
A cast-in-place and lithographically shaped mobile, monolithic polymer element for fluid flow control in microfluidic devices and method of manufacture. Microfluid flow control devices, or microvalves that provide for control of fluid or ionic current flow can be made incorporating a cast-in-place, mobile monolithic polymer element, disposed within a microchannel, and driven by either fluid or gas pressure against a retaining or sealing surface. The polymer elements are made by the application of lithographic methods to monomer mixtures formulated in such a way that the polymer will not bond to microchannel walls. The polymer elements can seal against pressures greater than 5000 psi, and have a response time on the order of milliseconds. By the use of energetic radiation it is possible to depolymerize selected regions of the polymer element to form shapes that cannot be produced by conventional lithographic patterning and would be impossible to machine.
Mobile Monolith Polymer Elements For Flow Control In Microfluidic Systems
Hasselbrink, Jr., Ernest F.; Rehm, Jason E.; Shepodd, Timothy J.; Kirby, Brian J.
2006-01-24
A cast-in-place and lithographically shaped mobile, monolithic polymer element for fluid flow control in microfluidic devices and method of manufacture. Microfluid flow control devices, or microvalves that provide for control of fluid or ionic current flow can be made incorporating a cast-in-place, mobile monolithic polymer element, disposed within a microchannel, and driven by fluid pressure (either liquid or gas) against a retaining or sealing surface. The polymer elements are made by the application of lithographic methods to monomer mixtures formulated in such a way that the polymer will not bond to microchannel walls. The polymer elements can seal against pressures greater than 5000 psi, and have a response time on the order of milliseconds. By the use of energetic radiation it is possible to depolymerize selected regions of the polymer element to form shapes that cannot be produced by conventional lithographic patterning and would be impossible to machine.
Mobile monolithic polymer elements for flow control in microfluidic devices
Hasselbrink, Jr., Ernest F.; Rehm, Jason E [Alameda, CA; Shepodd, Timothy J [Livermore, CA; Kirby, Brian J [San Francisco, CA
2005-11-11
A cast-in-place and lithographically shaped mobile, monolithic polymer element for fluid flow control in microfluidic devices and method of manufacture. Microfluid flow control devices, or microvalves that provide for control of fluid or ionic current flow can be made incorporating a cast-in-place, mobile monolithic polymer element, disposed within a microchannel, and driven by fluid pressure (either liquid or gas) against a retaining or sealing surface. The polymer elements are made by the application of lithographic methods to monomer mixtures formulated in such a way that the polymer will not bond to microchannel walls. The polymer elements can seal against pressures greater than 5000 psi, and have a response time on the order of milliseconds. By the use of energetic radiation it is possible to depolymerize selected regions of the polymer element to form shapes that cannot be produced by conventional lithographic patterning and would be impossible to machine.
40 CFR 1036.801 - Definitions.
Code of Federal Regulations, 2012 CFR
2012-07-01
... control device means any element of design that senses temperature, motive speed, engine RPM, transmission.... Emission control system means any device, system, or element of design that controls or reduces the... Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS CONTROL OF...
40 CFR 1036.801 - Definitions.
Code of Federal Regulations, 2014 CFR
2014-07-01
... control device means any element of design that senses temperature, motive speed, engine RPM, transmission.... Emission control system means any device, system, or element of design that controls or reduces the... Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS CONTROL OF...
Application of the control volume mixed finite element method to a triangular discretization
Naff, R.L.
2012-01-01
A two-dimensional control volume mixed finite element method is applied to the elliptic equation. Discretization of the computational domain is based in triangular elements. Shape functions and test functions are formulated on the basis of an equilateral reference triangle with unit edges. A pressure support based on the linear interpolation of elemental edge pressures is used in this formulation. Comparisons are made between results from the standard mixed finite element method and this control volume mixed finite element method. Published 2011. This article is a US Government work and is in the public domain in the USA. ?? 2012 John Wiley & Sons, Ltd. This article is a US Government work and is in the public domain in the USA.
Dual-loop model of the human controller
NASA Technical Reports Server (NTRS)
Hess, R. A.
1978-01-01
A dual-loop model of the human controller in single-axis compensatory tracking tasks is introduced. This model possesses an inner-loop closure that involves feeding back that portion of controlled element output rate that is due to control activity. A novel feature of the model is the explicit appearance of the human's internal representation of the manipulator-controlled element dynamics in the inner loop. The sensor inputs to the human controller are assumed to be system error and control force. The former can be sensed via visual, aural, or tactile displays, whereas the latter is assumed to be sensed in kinesthetic fashion. A set of general adaptive characteristics for the model is hypothesized, including a method for selecting simplified internal models of the manipulator-controlled element dynamics. It is demonstrated that the model can produce controller describing functions that closely approximate those measured in four laboratory tracking tasks in which the controlled element dynamics vary considerably in terms of ease of control. An empirically derived expression for the normalized injected error remnant spectrum is introduced.
Self-regulating proportionally controlled heating apparatus and technique
NASA Technical Reports Server (NTRS)
Strange, M. G. (Inventor)
1975-01-01
A self-regulating proportionally controlled heating apparatus and technique is provided wherein a single electrical resistance heating element having a temperature coefficient of resistance serves simultaneously as a heater and temperature sensor. The heating element is current-driven and the voltage drop across the heating element is monitored and a component extracted which is attributable to a change in actual temperature of the heating element from a desired reference temperature, so as to produce a resulting error signal. The error signal is utilized to control the level of the heater drive current and the actual heater temperature in a direction to reduce the noted temperature difference. The continuous nature of the process for deriving the error signal feedback information results in true proportional control of the heating element without the necessity for current-switching which may interfere with nearby sensitive circuits, and with no cyclical variation in the controlled temperature.
Method and apparatus for controlling carrier envelope phase
Chang, Zenghu [Manhattan, KS; Li, Chengquan [Sunnyvale, CA; Moon, Eric [Manhattan, KS
2011-12-06
A chirped pulse amplification laser system. The system generally comprises a laser source, a pulse modification apparatus including first and second pulse modification elements separated by a separation distance, a positioning element, a measurement device, and a feedback controller. The laser source is operable to generate a laser pulse and the pulse modification apparatus operable to modify at least a portion of the laser pulse. The positioning element is operable to reposition at least a portion of the pulse modification apparatus to vary the separation distance. The measurement device is operable to measure the carrier envelope phase of the generated laser pulse and the feedback controller is operable to control the positioning element based on the measured carrier envelope phase to vary the separation distance of the pulse modification elements and control the carrier envelope phase of laser pulses generated by the laser source.
Unified control/structure design and modeling research
NASA Technical Reports Server (NTRS)
Mingori, D. L.; Gibson, J. S.; Blelloch, P. A.; Adamian, A.
1986-01-01
To demonstrate the applicability of the control theory for distributed systems to large flexible space structures, research was focused on a model of a space antenna which consists of a rigid hub, flexible ribs, and a mesh reflecting surface. The space antenna model used is discussed along with the finite element approximation of the distributed model. The basic control problem is to design an optimal or near-optimal compensator to suppress the linear vibrations and rigid-body displacements of the structure. The application of an infinite dimensional Linear Quadratic Gaussian (LQG) control theory to flexible structure is discussed. Two basic approaches for robustness enhancement were investigated: loop transfer recovery and sensitivity optimization. A third approach synthesized from elements of these two basic approaches is currently under development. The control driven finite element approximation of flexible structures is discussed. Three sets of finite element basic vectors for computing functional control gains are compared. The possibility of constructing a finite element scheme to approximate the infinite dimensional Hamiltonian system directly, instead of indirectly is discussed.
Integrated command, control, communications and computation system functional architecture
NASA Technical Reports Server (NTRS)
Cooley, C. G.; Gilbert, L. E.
1981-01-01
The functional architecture for an integrated command, control, communications, and computation system applicable to the command and control portion of the NASA End-to-End Data. System is described including the downlink data processing and analysis functions required to support the uplink processes. The functional architecture is composed of four elements: (1) the functional hierarchy which provides the decomposition and allocation of the command and control functions to the system elements; (2) the key system features which summarize the major system capabilities; (3) the operational activity threads which illustrate the interrelationahip between the system elements; and (4) the interfaces which illustrate those elements that originate or generate data and those elements that use the data. The interfaces also provide a description of the data and the data utilization and access techniques.
Damper mechanism for nuclear reactor control elements
Taft, William Elwood
1976-01-01
A damper mechanism which provides a nuclear reactor control element decelerating function at the end of the scram stroke. The total damping function is produced by the combination of two assemblies, which operate in sequence. First, a tapered dashram assembly decelerates the control element to a lower velocity, after which a spring hydraulic damper assembly takes over to complete the final damping.
40 CFR 1042.901 - Definitions.
Code of Federal Regulations, 2014 CFR
2014-07-01
... part. Auxiliary emission control device means any element of design that senses temperature, vessel..., system, or element of design that controls or reduces the emissions of regulated pollutants from an... Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS CONTROL OF...
40 CFR 1042.901 - Definitions.
Code of Federal Regulations, 2011 CFR
2011-07-01
... part. Auxiliary emission control device means any element of design that senses temperature, vessel..., system, or element of design that controls or reduces the emissions of regulated pollutants from an... Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS CONTROL OF...
40 CFR 1042.901 - Definitions.
Code of Federal Regulations, 2010 CFR
2010-07-01
... part. Auxiliary emission control device means any element of design that senses temperature, vessel..., system, or element of design that controls or reduces the emissions of regulated pollutants from an... Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS CONTROL OF...
40 CFR 1042.901 - Definitions.
Code of Federal Regulations, 2012 CFR
2012-07-01
... part. Auxiliary emission control device means any element of design that senses temperature, vessel..., system, or element of design that controls or reduces the emissions of regulated pollutants from an... Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS CONTROL OF...
40 CFR 1037.801 - Definitions.
Code of Federal Regulations, 2012 CFR
2012-07-01
.... Auxiliary emission control device means any element of design that senses temperature, motive speed, engine... any device, system, or element of design that controls or reduces the emissions of regulated... Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS CONTROL OF...
40 CFR 1037.801 - Definitions.
Code of Federal Regulations, 2014 CFR
2014-07-01
.... Auxiliary emission control device means any element of design that senses temperature, motive speed, engine... any device, system, or element of design that controls or reduces the emissions of regulated... Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS CONTROL OF...
40 CFR 1042.901 - Definitions.
Code of Federal Regulations, 2013 CFR
2013-07-01
... part. Auxiliary emission control device means any element of design that senses temperature, vessel..., system, or element of design that controls or reduces the emissions of regulated pollutants from an... Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS CONTROL OF...
NASA Astrophysics Data System (ADS)
Kim, Gi-Woo; Wang, K. W.
2009-08-01
In this study, a nonlinear sliding-mode controller is designed for force tracking of a piezoelectric-hydraulic pump (PHP)-based actuation system, which is developed to replace the current electro-hydraulic actuation systems for automatic transmission (AT) friction elements, such as band brakes or clutches. By utilizing the PHP, one can eliminate the various hydraulic components (oil pump, regulating valve and control valve) in current ATs and achieve a simpler configuration with more efficient operation. With the derived governing equation of motion of the PHP-based actuation system integrated with the friction element (band brake), a switching control law is synthesized based on the sliding-mode theory. To evaluate the effectiveness of the proposed control law, its force tracking performance for the engagement of a friction element during an AT 1\\to 2 up-shift is examined experimentally. It is shown that one can successfully track the desired force trajectory for AT shift control with small tracking error. This study demonstrates the potential of the PHP as a new controllable actuation system for AT friction elements.
Health risk assessment of rare earth elements in cereals from mining area in Shandong, China.
Zhuang, Maoqiang; Wang, Liansen; Wu, Guangjian; Wang, Kebo; Jiang, Xiaofeng; Liu, Taibin; Xiao, Peirui; Yu, Lianlong; Jiang, Ying; Song, Jian; Zhang, Junli; Zhou, Jingyang; Zhao, Jinshan; Chu, Zunhua
2017-08-29
To investigate the concentrations of rare earth elements in cereals and assess human health risk through cereal consumption, a total of 327 cereal samples were collected from rare earth mining area and control area in Shandong, China. The contents of 14 rare earth elements were determined by Inductively Coupled Plasma-Mass Spectrometry (ICP-MS). The medians of total rare earth elements in cereals from mining and control areas were 74.22 μg/kg and 47.83 μg/kg, respectively, and the difference was statistically significant (P < 0.05). The wheat had the highest rare earth elements concentrations (109.39 μg/kg and 77.96 μg/kg for mining and control areas, respectively) and maize had the lowest rare earth elements concentrations (42.88 μg/kg and 30.25 μg/kg for mining and control areas, respectively). The rare earth elements distribution patterns for both areas were characterized by enrichment of light rare earth elements. The health risk assessment demonstrated that the estimated daily intakes of rare earth elements through cereal consumption were considerably lower than the acceptable daily intake (70 μg/kg bw). The damage to adults can be neglected, but more attention should be paid to the effects of continuous exposure to rare earth elements on children.
40 CFR 1039.801 - What definitions apply to this part?
Code of Federal Regulations, 2014 CFR
2014-07-01
... operation in water. Auxiliary emission-control device means any element of design that senses temperature... suppression operations. Emission-control system means any device, system, or element of design that controls... POLLUTION CONTROLS CONTROL OF EMISSIONS FROM NEW AND IN-USE NONROAD COMPRESSION-IGNITION ENGINES Definitions...
Compliance control with embedded neural elements
NASA Technical Reports Server (NTRS)
Venkataraman, S. T.; Gulati, S.
1992-01-01
The authors discuss a control approach that embeds the neural elements within a model-based compliant control architecture for robotic tasks that involve contact with unstructured environments. Compliance control experiments have been performed on actual robotics hardware to demonstrate the performance of contact control schemes with neural elements. System parameters were identified under the assumption that environment dynamics have a fixed nonlinear structure. A robotics research arm, placed in contact with a single degree-of-freedom electromechanical environment dynamics emulator, was commanded to move through a desired trajectory. The command was implemented by using a compliant control strategy.
NASA Astrophysics Data System (ADS)
Pries, V. V.; Proskuriakov, N. E.
2018-04-01
To control the assembly quality of multi-element mass-produced products on automatic rotor lines, control methods with operational feedback are required. However, due to possible failures in the operation of the devices and systems of automatic rotor line, there is always a real probability of getting defective (incomplete) products into the output process stream. Therefore, a continuous sampling control of the products completeness, based on the use of statistical methods, remains an important element in managing the quality of assembly of multi-element mass products on automatic rotor lines. The feature of continuous sampling control of the multi-element products completeness in the assembly process is its breaking sort, which excludes the possibility of returning component parts after sampling control to the process stream and leads to a decrease in the actual productivity of the assembly equipment. Therefore, the use of statistical procedures for continuous sampling control of the multi-element products completeness when assembled on automatic rotor lines requires the use of such sampling plans that ensure a minimum size of control samples. Comparison of the values of the limit of the average output defect level for the continuous sampling plan (CSP) and for the automated continuous sampling plan (ACSP) shows the possibility of providing lower limit values for the average output defects level using the ACSP-1. Also, the average sample size when using the ACSP-1 plan is less than when using the CSP-1 plan. Thus, the application of statistical methods in the assembly quality management of multi-element products on automatic rotor lines, involving the use of proposed plans and methods for continuous selective control, will allow to automating sampling control procedures and the required level of quality of assembled products while minimizing sample size.
NASA Technical Reports Server (NTRS)
Pla, Frederic G. (Inventor); Renshaw, Anthony A. (Inventor); Rajiyah, Harindra (Inventor); Hedeen, Robert A. (Inventor)
1995-01-01
A noise source for an aircraft engine active noise cancellation system in which the resonant frequency of a noise radiating element is tuned to permit noise cancellation over a wide range of frequencies. The resonant frequency of the noise radiating element is tuned by an expandable ring embedded in the noise radiating element. Excitation of the ring causes expansion or contraction of the ring, thereby varying the stress in the noise radiating element. The ring is actuated by a controller which receives input of a feedback signal proportional to displacement of the noise radiating element and a signal corresponding to the blade passage frequency of the engine's fan. In response, the controller determines a control signal which is sent to the ring, causing the ring to expand or contract. Instead of a single ring embedded in the noise radiating panel, a first expandable ring can be bonded to one side of the noise radiating element, and a second expandable ring can be bonded to the other side.
DOE R&D Accomplishments Database
Burr, B.; Burr, F.A.
1980-05-28
This report describes our initial attempts at the molecular characterization of a maize controlling element. We have prepared a cDNA probe and used it to detect changes at a locus where Ds elements are found. Evidence of their presence are indicated by changes in the restriction patterns, but there is as yet no information on the physical nature of the controlling elements nor on the kinds of rearrangements they cause.
Elements of active vibration control for rotating machinery
NASA Technical Reports Server (NTRS)
Ulbrich, Heinz
1990-01-01
The success or failure of active vibration control is determined by the availability of suitable actuators, modeling of the entire system including all active elements, positioning of the actuators and sensors, and implementation of problem-adapted control concepts. All of these topics are outlined and their special problems are discussed in detail. Special attention is given to efficient modeling of systems, especially for considering the active elements. Finally, design methods for and the application of active vibration control on rotating machinery are demonstrated by several real applications.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chen, Yan; Treado, Stephen J.; Messner, John I.
Building control systems for Heating, Ventilation, and Air Conditioning (HVAC) play a key role in realizing the functionality and operation of building systems and components. Building Control Knowledge (BCK) is the logic and algorithms embedded throughout building control system. There are different methods to represent the BCK. These methods differ in the selection of BCK representing elements and the format of those elements. There is a lack of standard data schema, for storing, retrieving, and reusing structured BCK. In this study, a modular data schema is created for BCK representation. The data schema contains eleven representing elements, i.e., control modulemore » name, operation mode, system schematic, control flow diagram, data point, alarm, parameter, control sequence, function, and programming code. Each element is defined with specific attributes. This data schema is evaluated through a case study demonstration. The demonstration shows a new way to represent the BCK with standard formats.« less
NASA Technical Reports Server (NTRS)
Mei, Chuh; Shi, Yacheng
1997-01-01
A coupled finite element (FE) and boundary element (BE) approach is presented to model full coupled structural/acoustic/piezoelectric systems. The dual reciprocity boundary element method is used so that the natural frequencies and mode shapes of the coupled system can be obtained, and to extend this approach to time dependent problems. The boundary element method is applied to interior acoustic domains, and the results are very accurate when compared with limited exact solutions. Structural-acoustic problems are then analyzed with the coupled finite element/boundary element method, where the finite element method models the structural domain and the boundary element method models the acoustic domain. Results for a system consisting of an isotropic panel and a cubic cavity are in good agreement with exact solutions and experiment data. The response of a composite panel backed cavity is then obtained. The results show that the mass and stiffness of piezoelectric layers have to be considered. The coupled finite element and boundary element equations are transformed into modal coordinates, which is more convenient for transient excitation. Several transient problems are solved based on this formulation. Two control designs, a linear quadratic regulator (LQR) and a feedforward controller, are applied to reduce the acoustic pressure inside the cavity based on the equations in modal coordinates. The results indicate that both controllers can reduce the interior acoustic pressure and the plate deflection.
40 CFR 1045.801 - What definitions apply to this part?
Code of Federal Regulations, 2013 CFR
2013-07-01
... means any device, system, or element of design that someone can adjust (including those which are... emission control device means any element of design that senses temperature, motive speed, engine RPM... on a continuous mixture of those fuels. Emission control system means any device, system, or element...
Locomotion of Amorphous Surface Robots
NASA Technical Reports Server (NTRS)
Bradley, Arthur T. (Inventor)
2018-01-01
An amorphous robot includes a compartmented bladder containing fluid, a valve assembly, and an outer layer encapsulating the bladder and valve assembly. The valve assembly draws fluid from a compartment(s) and discharges the drawn fluid into a designated compartment to displace the designated compartment with respect to the surface. Another embodiment includes elements each having a variable property, an outer layer that encapsulates the elements, and a control unit. The control unit energizes a designated element to change its variable property, thereby moving the designated element. The elements may be electromagnetic spheres with a variable polarity or shape memory polymers with changing shape and/or size. Yet another embodiment includes an elongated flexible tube filled with ferrofluid, a moveable electromagnet, an actuator, and a control unit. The control unit energizes the electromagnet and moves the electromagnet via the actuator to magnetize the ferrofluid and lengthen the flexible tube.
Locomotion of Amorphous Surface Robots
NASA Technical Reports Server (NTRS)
Bradley, Arthur T. (Inventor)
2016-01-01
An amorphous robot includes a compartmented bladder containing fluid, a valve assembly, and an outer layer encapsulating the bladder and valve assembly. The valve assembly draws fluid from a compartment(s) and discharges the drawn fluid into a designated compartment to displace the designated compartment with respect to the surface. Another embodiment includes elements each having a variable property, an outer layer that encapsulates the elements, and a control unit. The control unit energizes a designated element to change its variable property, thereby moving the designated element. The elements may be electromagnetic spheres with a variable polarity or shape memory polymers with changing shape and/or size. Yet another embodiment includes an elongated flexible tube filled with ferrofluid, a moveable electromagnet, an actuator, and a control unit. The control unit energizes the electromagnet and moves the electromagnet via the actuator to magnetize the ferrofluid and lengthen the flexible tube.
Locomotion of Amorphous Surface Robots
NASA Technical Reports Server (NTRS)
Bradley, Arthur T. (Inventor)
2014-01-01
An amorphous robot includes a compartmented bladder containing fluid, a valve assembly, and an outer layer encapsulating the bladder and valve assembly. The valve assembly draws fluid from a compartment(s) and discharges the drawn fluid into a designated compartment to displace the designated compartment with respect to the surface. Another embodiment includes elements each having a variable property, an outer layer that encapsulates the elements, and a control unit. The control unit energizes a designated element to change its variable property, thereby moving the designated element. The elements may be electromagnetic spheres with a variable polarity or shape memory polymers with changing shape and/or size. Yet another embodiment includes an elongated flexible tube filled with ferrofluid, a moveable electromagnet, an actuator, and a control unit. The control unit energizes the electromagnet and moves the electromagnet via the actuator to magnetize the ferrofluid and lengthen the flexible tube.
40 CFR 1054.801 - What definitions apply to this part?
Code of Federal Regulations, 2014 CFR
2014-07-01
... of this part. Auxiliary emission control device means any element of design that senses temperature... continuous mixture of those fuels. Emission control system means any device, system, or element of design... POLLUTION CONTROLS CONTROL OF EMISSIONS FROM NEW, SMALL NONROAD SPARK-IGNITION ENGINES AND EQUIPMENT...
40 CFR 1054.801 - What definitions apply to this part?
Code of Federal Regulations, 2011 CFR
2011-07-01
... of this part. Auxiliary emission control device means any element of design that senses temperature... continuous mixture of those fuels. Emission control system means any device, system, or element of design... POLLUTION CONTROLS CONTROL OF EMISSIONS FROM NEW, SMALL NONROAD SPARK-IGNITION ENGINES AND EQUIPMENT...
40 CFR 1054.801 - What definitions apply to this part?
Code of Federal Regulations, 2012 CFR
2012-07-01
... of this part. Auxiliary emission control device means any element of design that senses temperature... continuous mixture of those fuels. Emission control system means any device, system, or element of design... POLLUTION CONTROLS CONTROL OF EMISSIONS FROM NEW, SMALL NONROAD SPARK-IGNITION ENGINES AND EQUIPMENT...
40 CFR 1054.801 - What definitions apply to this part?
Code of Federal Regulations, 2010 CFR
2010-07-01
... of this part. Auxiliary emission control device means any element of design that senses temperature... continuous mixture of those fuels. Emission control system means any device, system, or element of design... POLLUTION CONTROLS CONTROL OF EMISSIONS FROM NEW, SMALL NONROAD SPARK-IGNITION ENGINES AND EQUIPMENT...
40 CFR 1054.801 - What definitions apply to this part?
Code of Federal Regulations, 2013 CFR
2013-07-01
... of this part. Auxiliary emission control device means any element of design that senses temperature... continuous mixture of those fuels. Emission control system means any device, system, or element of design... POLLUTION CONTROLS CONTROL OF EMISSIONS FROM NEW, SMALL NONROAD SPARK-IGNITION ENGINES AND EQUIPMENT...
Kwan, C T; Tsang, S L; Krumlauf, R; Sham, M H
2001-04-01
The expression pattern of the mouse Hoxb3 gene is exceptionally complex and dynamic compared with that of other members of the Hoxb cluster. There are multiple types of transcripts for Hoxb3 gene, and the anterior boundaries of its expression vary at different stages of development. Two enhancers flanking Hoxb3 on the 3' and 5' sides regulate Hoxb2 and Hoxb4, respectively, and these control regions define the two ends of a 28-kb interval in and around the Hoxb3 locus. To assay the regulatory potential of DNA fragments in this interval we have used transgenic analysis with a lacZ reporter gene to locate cis-elements for directing the dynamic patterns of Hoxb3 expression. Our detailed analysis has identified four new and widely spaced cis-acting regulatory regions that can together account for major aspects of the Hoxb3 expression pattern. Elements Ib, IIIa, and IVb control gene expression in neural and mesodermal tissues; element Va controls mesoderm-specific gene expression. The most anterior neural expression domain of Hoxb3 is controlled by an r5 enhancer (element IVa); element IIIa directs reporter expression in the anterior spinal cord and hindbrain up to r6, and the region A enhancer (in element I) mediates posterior neural expression. Hence, the regulation of segmental expression of Hoxb3 in the hindbrain is different from that of Hoxa3, as two separate enhancer elements contribute to expression in r5 and r6. The mesoderm-specific element (Va) directs reporter expression to prevertebra C1 at 12.5 dpc, which is the anterior limit of paraxial mesoderm expression for Hoxb3. When tested in combinations, these cis-elements appear to work as modules in an additive manner to recapitulate the major endogenous expression patterns of Hoxb3 during embryogenesis. Together our study shows that multiple control elements direct reporter gene expression in diverse tissue-, temporal-, and spatially restricted subset of the endogenous Hoxb3 expression domains and work in concert to control the neural and mesodermal patterns of expression. Copyright 2001 Academic Press.
Zhuang, Maoqiang; Zhao, Jinshan; Li, Suyun; Liu, Danru; Wang, Kebo; Xiao, Peirui; Yu, Lianlong; Jiang, Ying; Song, Jian; Zhou, Jingyang; Wang, Liansen; Chu, Zunhua
2017-02-01
To investigate the concentrations of rare earth elements in vegetables and assess human health risk through vegetable consumption, a total of 301 vegetable samples were collected from mining area and control area in Shandong, China. The contents of 14 rare earth elements were determined by Inductively Coupled Plasma-Mass Spectrometry (ICP-MS). The total rare earth elements in vegetables from mining and control areas were 94.08 μg kg -1 and 38.67 μg kg -1 , respectively, and the difference was statistically significant (p < 0.05). The leaf vegetable had the highest rare earth elements concentration (984.24 μg kg -1 and 81.24 μg kg -1 for mining and control areas, respectively) and gourd vegetable had the lowest rare earth elements concentration (37.34 μg kg -1 and 24.63 μg kg -1 for mining and control areas, respectively). For both areas, the rare earth elements concentration in vegetables declined in the order of leaf vegetable > taproot vegetable > alliaceous vegetable > gourd vegetable. The rare earth elements distribution patterns for both areas were characterized by enrichment of light rare earth elements. The health risk assessment demonstrated that the estimated daily intakes (0.69 μg kg -1 d -1 and 0.28 μg kg -1 d -1 for mining and control areas, respectively) of rare earth elements through vegetable consumption were significantly lower than the acceptable daily intake (70 μg kg -1 d -1 ). The damage to adults can be neglected, but more attention should be paid to the effects of continuous exposure to low levels of rare earth elements on children. Copyright © 2016 Elsevier Ltd. All rights reserved.
Pituitary gland levels of mercury, selenium, iron, and zinc in an Alzheimer`s disease study
DOE Office of Scientific and Technical Information (OSTI.GOV)
Cornett, C.R.; Markesbery, W.R.; Wekstein, D.R.
1996-12-31
Mercury, iron, selenium, and zinc imbalances have been observed in comparisons between Alzheimer`s disease (AD) and control subject brains. Analyses of the pituitary gland have demonstrated that this organ retains relatively high concentrations of trace elements, including mercury, iron, and zinc. Our previous work has shown that the pituitary glands of AD and control subjects are typically higher in these trace elements than brain samples from the same subject. Instrumental neutron activation analysis (INAA) was used to compare the pituitary trace element levels of AD and control subjects. This study also describes the intrasubject relationships of brain trace element levelsmore » to those in the pituitary gland of AD and control subjects.« less
40 CFR 1039.801 - What definitions apply to this part?
Code of Federal Regulations, 2012 CFR
2012-07-01
... operation in water. Auxiliary emission-control device means any element of design that senses temperature... element of design that controls or reduces the emissions of regulated pollutants from an engine. Emission... POLLUTION CONTROLS CONTROL OF EMISSIONS FROM NEW AND IN-USE NONROAD COMPRESSION-IGNITION ENGINES Definitions...
40 CFR 1039.801 - What definitions apply to this part?
Code of Federal Regulations, 2010 CFR
2010-07-01
... operation in water. Auxiliary emission-control device means any element of design that senses temperature... element of design that controls or reduces the emissions of regulated pollutants from an engine. Emission... POLLUTION CONTROLS CONTROL OF EMISSIONS FROM NEW AND IN-USE NONROAD COMPRESSION-IGNITION ENGINES Definitions...
40 CFR 1039.801 - What definitions apply to this part?
Code of Federal Regulations, 2011 CFR
2011-07-01
... operation in water. Auxiliary emission-control device means any element of design that senses temperature... element of design that controls or reduces the emissions of regulated pollutants from an engine. Emission... POLLUTION CONTROLS CONTROL OF EMISSIONS FROM NEW AND IN-USE NONROAD COMPRESSION-IGNITION ENGINES Definitions...
Low current extended duration spark ignition system
Waters, Stephen Howard; Chan, Anthony Kok-Fai
2005-08-30
A system for firing a spark plug is disclosed. The system includes a timing controller configured to send a first timing signal and a second timing signal. The system also includes an ignition transformer having a primary winding and a secondary winding and a spark-plug that is operably associated with the secondary winding. A first switching element is disposed between the timing controller and the primary winding of the ignition transformer. The first switching element controls a supply of power to the primary winding based on the first timing signal. Also, a second switching element is disposed between the timing controller and the primary winding of the ignition transformer. The second switching element controls the supply of power to the primary winding based on the second timing signal. A method for firing a spark plug is also disclosed.
An Ontology for Identifying Cyber Intrusion Induced Faults in Process Control Systems
NASA Astrophysics Data System (ADS)
Hieb, Jeffrey; Graham, James; Guan, Jian
This paper presents an ontological framework that permits formal representations of process control systems, including elements of the process being controlled and the control system itself. A fault diagnosis algorithm based on the ontological model is also presented. The algorithm can identify traditional process elements as well as control system elements (e.g., IP network and SCADA protocol) as fault sources. When these elements are identified as a likely fault source, the possibility exists that the process fault is induced by a cyber intrusion. A laboratory-scale distillation column is used to illustrate the model and the algorithm. Coupled with a well-defined statistical process model, this fault diagnosis approach provides cyber security enhanced fault diagnosis information to plant operators and can help identify that a cyber attack is underway before a major process failure is experienced.
Low exhaust temperature electrically heated particulate matter filter system
Gonze, Eugene V [Pinckney, MI; Paratore, Jr., Michael J.; Bhatia, Garima [Bangalore, IN
2012-02-14
A system includes a particulate matter (PM) filter, a sensor, a heating element, and a control module. The PM filter includes with an upstream end that receives exhaust gas, a downstream end and multiple zones. The sensor detects a temperature of the exhaust gas. The control module controls current to the heating element to convection heat one of the zones and initiate a regeneration process. The control module selectively increases current to the heating element relative to a reference regeneration current level when the temperature is less than a predetermined temperature.
Programmable phase plate for tool modification in laser machining applications
Thompson Jr., Charles A.; Kartz, Michael W.; Brase, James M.; Pennington, Deanna; Perry, Michael D.
2004-04-06
A system for laser machining includes a laser source for propagating a laser beam toward a target location, and a spatial light modulator having individual controllable elements capable of modifying a phase profile of the laser beam to produce a corresponding irradiance pattern on the target location. The system also includes a controller operably connected to the spatial light modulator for controlling the individual controllable elements. By controlling the individual controllable elements, the phase profile of the laser beam may be modified into a desired phase profile so as to produce a corresponding desired irradiance pattern on the target location capable of performing a machining operation on the target location.
Code of Federal Regulations, 2010 CFR
2010-10-01
... 42 Public Health 4 2010-10-01 2010-10-01 false Basic elements of the Medicaid quality control (MQC... & MEDICAID SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL ASSISTANCE PROGRAMS STATE ORGANIZATION AND GENERAL ADMINISTRATION Quality Control Medicaid Quality Control (mqc) Claims Processing...
42 CFR 431.810 - Basic elements of the Medicaid eligibility quality control (MEQC) program.
Code of Federal Regulations, 2010 CFR
2010-10-01
... 42 Public Health 4 2010-10-01 2010-10-01 false Basic elements of the Medicaid eligibility quality control (MEQC) program. 431.810 Section 431.810 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES... GENERAL ADMINISTRATION Quality Control Medicaid Eligibility Quality Control (meqc) Program § 431.810 Basic...
40 CFR 1033.901 - Definitions.
Code of Federal Regulations, 2011 CFR
2011-07-01
... means any device, system, or element of design that controls or reduces the regulated emissions from a... Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS CONTROL OF... means any device, system, or element of design that someone can adjust (including those which are...
40 CFR 1033.901 - Definitions.
Code of Federal Regulations, 2013 CFR
2013-07-01
... means any device, system, or element of design that controls or reduces the regulated emissions from a... Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS CONTROL OF... means any device, system, or element of design that someone can adjust (including those which are...
40 CFR 1033.901 - Definitions.
Code of Federal Regulations, 2010 CFR
2010-07-01
... means any device, system, or element of design that controls or reduces the regulated emissions from a... Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS CONTROL OF... means any device, system, or element of design that someone can adjust (including those which are...
40 CFR 1033.901 - Definitions.
Code of Federal Regulations, 2014 CFR
2014-07-01
... means any device, system, or element of design that controls or reduces the regulated emissions from a... Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS CONTROL OF... means any device, system, or element of design that someone can adjust (including those which are...
40 CFR 1033.901 - Definitions.
Code of Federal Regulations, 2012 CFR
2012-07-01
... means any device, system, or element of design that controls or reduces the regulated emissions from a... Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS CONTROL OF... means any device, system, or element of design that someone can adjust (including those which are...
Control device for prosthetic urinary sphincter cuff
NASA Technical Reports Server (NTRS)
Reinicke, Robert H. (Inventor)
1983-01-01
A device for controlling flow of fluid to and from a resilient inflatable cuff implanted about the urethra to control flow of urine therethrough. The device comprises a flexible bulb reservoir and a control unit that includes a manually operated valve that opens automatically when the bulb is squeezed to force fluid into the cuff for closing the urethra. The control unit also includes a movable valve seat member having a relatively large area exposed to pressure of fluid in a chamber that is connected to the cuff and which moves to a position in which the valve member is unseated by an abutment when fluid pressure in the chamber exceeds a predetermined value to thereby relieve excess fluid pressure in the cuff. The arrangement is such that the valve element is held closed against the seat member by the full differential in fluid pressures acting on both sides of the valve element until the seat member is moved away from the valve element to thus insure positive closing of the valve element until the seat member is moved out of engagement with the valve element by excess pressure differential.
High-speed optical phase-shifting apparatus
Zortman, William A.
2016-11-08
An optical phase shifter includes an optical waveguide, a plurality of partial phase shifting elements arranged sequentially, and control circuitry electrically coupled to the partial phase shifting elements. The control circuitry is adapted to provide an activating signal to each of the N partial phase shifting elements such that the signal is delayed by a clock cycle between adjacent partial phase shifting elements in the sequence. The transit time for a guided optical pulse train between the input edges of consecutive partial phase shifting elements in the sequence is arranged to be equal to a clock cycle, thereby enabling pipelined processing of the optical pulses.
About development of automation control systems
NASA Astrophysics Data System (ADS)
Myshlyaev, L. P.; Wenger, K. G.; Ivushkin, K. A.; Makarov, V. N.
2018-05-01
The shortcomings of approaches to the development of modern control automation systems and ways of their improvement are given: the correct formation of objects for study and optimization; a joint synthesis of control objects and control systems, an increase in the structural diversity of the elements of control systems. Diagrams of control systems with purposefully variable structure of their elements are presented. Structures of control algorithms for an object with a purposefully variable structure are given.
40 CFR 86.1803-01 - Definitions.
Code of Federal Regulations, 2013 CFR
2013-07-01
... procurement. Auxiliary Emission Control Device (AECD) means any element of design which senses temperature... components are those components which are designed primarily for emission control, or whose failure may... system as a means of providing electrical energy. Element of design means any control system (i.e...
40 CFR 136.7 - Quality assurance and quality control.
Code of Federal Regulations, 2014 CFR
2014-07-01
... quality control elements, where applicable, into the laboratory's documented standard operating procedure... quality control elements must be clearly documented in the written standard operating procedure for each... Methods contains QA/QC procedures in the Part 1000 section of the Standard Methods Compendium. The...
40 CFR 136.7 - Quality assurance and quality control.
Code of Federal Regulations, 2013 CFR
2013-07-01
... quality control elements, where applicable, into the laboratory's documented standard operating procedure... quality control elements must be clearly documented in the written standard operating procedure for each... Methods contains QA/QC procedures in the Part 1000 section of the Standard Methods Compendium. The...
40 CFR 136.7 - Quality assurance and quality control.
Code of Federal Regulations, 2012 CFR
2012-07-01
... quality control elements, where applicable, into the laboratory's documented standard operating procedure... quality control elements must be clearly documented in the written standard operating procedure for each... Methods contains QA/QC procedures in the Part 1000 section of the Standard Methods Compendium. The...
49 CFR 236.576 - Roadway element.
Code of Federal Regulations, 2010 CFR
2010-10-01
..., MAINTENANCE, AND REPAIR OF SIGNAL AND TRAIN CONTROL SYSTEMS, DEVICES, AND APPLIANCES Automatic Train Stop, Train Control and Cab Signal Systems Inspection and Tests; Roadway § 236.576 Roadway element. Roadway...
49 CFR 236.576 - Roadway element.
Code of Federal Regulations, 2011 CFR
2011-10-01
..., MAINTENANCE, AND REPAIR OF SIGNAL AND TRAIN CONTROL SYSTEMS, DEVICES, AND APPLIANCES Automatic Train Stop, Train Control and Cab Signal Systems Inspection and Tests; Roadway § 236.576 Roadway element. Roadway...
Adaptive beam shaping by controlled thermal lensing in optical elements
NASA Astrophysics Data System (ADS)
Arain, Muzammil A.; Quetschke, Volker; Gleason, Joseph; Williams, Luke F.; Rakhmanov, Malik; Lee, Jinho; Cruz, Rachel J.; Mueller, Guido; Tanner, D. B.; Reitze, David. H.
2007-04-01
We describe an adaptive optical system for use as a tunable focusing element. The system provides adaptive beam shaping via controlled thermal lensing in the optical elements. The system is agile, remotely controllable, touch free, and vacuum compatible; it offers a wide dynamic range, aberration-free focal length tuning, and can provide both positive and negative lensing effects. Focusing is obtained through dynamic heating of an optical element by an external pump beam. The system is especially suitable for use in interferometric gravitational wave interferometers employing high laser power, allowing for in situ control of the laser modal properties and compensation for thermal lensing of the primary laser. Using CO2 laser heating of fused-silica substrates, we demonstrate a focal length variable from infinity to 4.0 m, with a slope of 0.082 diopter/W of absorbed heat. For on-axis operation, no higher-order modes are introduced by the adaptive optical element. Theoretical modeling of the induced optical path change and predicted thermal lens agrees well with measurement.
Development of an adaptive hp-version finite element method for computational optimal control
NASA Technical Reports Server (NTRS)
Hodges, Dewey H.; Warner, Michael S.
1994-01-01
In this research effort, the usefulness of hp-version finite elements and adaptive solution-refinement techniques in generating numerical solutions to optimal control problems has been investigated. Under NAG-939, a general FORTRAN code was developed which approximated solutions to optimal control problems with control constraints and state constraints. Within that methodology, to get high-order accuracy in solutions, the finite element mesh would have to be refined repeatedly through bisection of the entire mesh in a given phase. In the current research effort, the order of the shape functions in each element has been made a variable, giving more flexibility in error reduction and smoothing. Similarly, individual elements can each be subdivided into many pieces, depending on the local error indicator, while other parts of the mesh remain coarsely discretized. The problem remains to reduce and smooth the error while still keeping computational effort reasonable enough to calculate time histories in a short enough time for on-board applications.
Adaptive beam shaping by controlled thermal lensing in optical elements.
Arain, Muzammil A; Quetschke, Volker; Gleason, Joseph; Williams, Luke F; Rakhmanov, Malik; Lee, Jinho; Cruz, Rachel J; Mueller, Guido; Tanner, D B; Reitze, David H
2007-04-20
We describe an adaptive optical system for use as a tunable focusing element. The system provides adaptive beam shaping via controlled thermal lensing in the optical elements. The system is agile, remotely controllable, touch free, and vacuum compatible; it offers a wide dynamic range, aberration-free focal length tuning, and can provide both positive and negative lensing effects. Focusing is obtained through dynamic heating of an optical element by an external pump beam. The system is especially suitable for use in interferometric gravitational wave interferometers employing high laser power, allowing for in situ control of the laser modal properties and compensation for thermal lensing of the primary laser. Using CO(2) laser heating of fused-silica substrates, we demonstrate a focal length variable from infinity to 4.0 m, with a slope of 0.082 diopter/W of absorbed heat. For on-axis operation, no higher-order modes are introduced by the adaptive optical element. Theoretical modeling of the induced optical path change and predicted thermal lens agrees well with measurement.
Moore, R.V.; Bowen, J.H.; Dent, K.H.
1958-12-01
A heterogeneous, natural uranium fueled, solid moderated, gas cooled reactor is described, in which the fuel elements are in the form of elongated rods and are dlsposed within vertical coolant channels ln the moderator symmetrically arranged as a regular lattice in groups. This reactor employs control rods which operate in vertical channels in the moderator so that each control rod is centered in one of the fuel element groups. The reactor is enclosed in a pressure vessel which ls provided with access holes at the top to facilitate loading and unloadlng of the fuel elements, control rods and control rod driving devices.
A Review of International Space Station Habitable Element Equipment Offgassing Characteristics
NASA Technical Reports Server (NTRS)
Perry, Jay L.
2010-01-01
Crewed spacecraft trace contaminant control employs both passive and active methods to achieve acceptable cabin atmospheric quality. Passive methods include carefully selecting materials of construction, employing clean manufacturing practices, and minimizing systems and payload operational impacts to the cabin environment. Materials selection and manufacturing processes constitute the first level of equipment offgassing control. An element-level equipment offgassing test provides preflight verification that passive controls have been successful. Offgassing test results from multiple International Space Station (ISS) habitable elements and cargo vehicles are summarized and implications for active contamination control equipment design are discussed
Misra, S.; Buratowski, R. M.; Ohkawa, T.; Rio, D. C.
1993-01-01
P element transposition in Drosophila is controlled by the cytotype regulatory state: in P cytotype, transposition is repressed, whereas in M cytotype, transposition can occur. P cytotype is determined by a combination of maternally inherited factors and chromosomal P elements in the zygote. Transformant strains containing single elements that encoded the 66-kD P element protein zygotically repressed transposition, but did not display the maternal repression characteristic of P cytotype. Upon mobilization to new genomic positions, some of these repressor elements showed significant maternal repression of transposition in genetic assays, involving a true maternal effect. Thus, the genomic position of repressor elements can determine the maternal vs. zygotic inheritance of P cytotype. Immunoblotting experiments indicate that this genomic position effect does not operate solely by controlling the expression level of the 66-kD repressor protein during oogenesis. Likewise, P element derivatives containing the hsp26 maternal regulator sequence expressed high levels of the 66-kD protein during oogenesis, but showed no detectable maternal repression. These data suggest that the location of a repressor element in the genome may determine maternal inheritance of P cytotype by a mechanism involving more than the overall level of expression of the 66-kD protein in the ovary. PMID:8293979
Passive thermo-optic feedback for robust athermal photonic systems
Rakich, Peter T.; Watts, Michael R.; Nielson, Gregory N.
2015-06-23
Thermal control devices, photonic systems and methods of stabilizing a temperature of a photonic system are provided. A thermal control device thermally coupled to a substrate includes a waveguide for receiving light, an absorption element optically coupled to the waveguide for converting the received light to heat and an optical filter. The optical filter is optically coupled to the waveguide and thermally coupled to the absorption element. An operating point of the optical filter is tuned responsive to the heat from the absorption element. When the operating point is less than a predetermined temperature, the received light is passed to the absorption element via the optical filter. When the operating point is greater than or equal to the predetermined temperature, the received light is transmitted out of the thermal control device via the optical filter, without being passed to the absorption element.
Underwater hydraulic shock shovel control system
NASA Astrophysics Data System (ADS)
Liu, He-Ping; Luo, A.-Ni; Xiao, Hai-Yan
2008-06-01
The control system determines the effectiveness of an underwater hydraulic shock shovel. This paper begins by analyzing the working principles of these shovels and explains the importance of their control systems. A new type of control system’s mathematical model was built and analyzed according to those principles. Since the initial control system’s response time could not fulfill the design requirements, a PID controller was added to the control system. System response time was still slower than required, so a neural network was added to nonlinearly regulate the proportional element, integral element and derivative element coefficients of the PID controller. After these improvements to the control system, system parameters fulfilled the design requirements. The working performance of electrically-controlled parts such as the rapidly moving high speed switch valve is largely determined by the control system. Normal control methods generally can’t satisfy a shovel’s requirements, so advanced and normal control methods were combined to improve the control system, bringing good results.
NASA Technical Reports Server (NTRS)
Myers, William; Winter, Steve
2006-01-01
The General Electric Reliable and Affordable Controls effort under the NASA Advanced Subsonic Technology (AST) Program has designed, fabricated, and tested advanced controls hardware and software to reduce emissions and improve engine safety and reliability. The original effort consisted of four elements: 1) a Hydraulic Multiplexer; 2) Active Combustor Control; 3) a Variable Displacement Vane Pump (VDVP); and 4) Intelligent Engine Control. The VDVP and Intelligent Engine Control elements were cancelled due to funding constraints and are reported here only to the state they progressed. The Hydraulic Multiplexing element developed and tested a prototype which improves reliability by combining the functionality of up to 16 solenoids and servo-valves into one component with a single electrically powered force motor. The Active Combustor Control element developed intelligent staging and control strategies for low emission combustors. This included development and tests of a Controlled Pressure Fuel Nozzle for fuel sequencing, a Fuel Multiplexer for individual fuel cup metering, and model-based control logic. Both the Hydraulic Multiplexer and Controlled Pressure Fuel Nozzle system were cleared for engine test. The Fuel Multiplexer was cleared for combustor rig test which must be followed by an engine test to achieve full maturation.
Preparation of thin film silver fluoride electrodes from constituent elements
NASA Technical Reports Server (NTRS)
Odonnell, P. M.
1972-01-01
The feasibility of preparing thin-film metal fluoride electrodes from the elemental constituents has been demonstrated. Silver fluoride cathodes were prepared by deposition of silver on a conducting graphite substrate followed by fluorination under controlled conditions using elemental fluorine. The resulting electrodes were of high purity, and the variables such as size, shape, and thickness were easily controlled.
Alien liquid detector and control
DOE Office of Scientific and Technical Information (OSTI.GOV)
Potter, B.M.
An alien liquid detector employs a monitoring element and an energizing circuit for maintaining the temperature of the monitoring element substantially above ambient temperature. For this purpose an electronic circit controls a flow of heating current to the monitoring element. The presence of an alien liquid is detected by sensing a predetermined change in heating current flow to the monitoring element, e.g., to distinguish between water and oil. In preferred embodiments the monitoring element is a thermistor whose resistance is compared with a reference resistance and heating current through the thermistor is controlled in accordance with the difference. In onemore » embodiment a bridge circuit senses the resistance difference; the difference may be sensed by an operational amplifier arrangement. Features of the invention include positioning the monitoring element at the surface of water, slightly immersed, so that the power required to maintain the thermistor temperature substantially above ambient temperature serves to detect presence of oil pollution at the surface.« less
Design Considerations for Gun Propellant Climatic Storage Chambers.
1982-11-01
Schematic diagram of thermal element 5 4. Prototype Lhermal element 6 5. Power control circuit diagram 7 6. Power control module 7 7. Temperature...plates. Each plate is powered through a triac and temperature control circuit as shown in figure 5. Figure 6 is a photograph of an assembled power control...SHEATER PLATES Figure 5. Power control circuit diagram 4 f Figure 6. Power control module WSR.L-0295-TR -8- Figure 7. Temperature control module 9 -WSRL
Rolling-Element Fatigue Testing and Data Analysis - A Tutorial
NASA Technical Reports Server (NTRS)
Vlcek, Brian L.; Zaretsky, Erwin V.
2011-01-01
In order to rank bearing materials, lubricants and other design variables using rolling-element bench type fatigue testing of bearing components and full-scale rolling-element bearing tests, the investigator needs to be cognizant of the variables that affect rolling-element fatigue life and be able to maintain and control them within an acceptable experimental tolerance. Once these variables are controlled, the number of tests and the test conditions must be specified to assure reasonable statistical certainty of the final results. There is a reasonable correlation between the results from elemental test rigs with those results obtained with full-scale bearings. Using the statistical methods of W. Weibull and L. Johnson, the minimum number of tests required can be determined. This paper brings together and discusses the technical aspects of rolling-element fatigue testing and data analysis as well as making recommendations to assure quality and reliable testing of rolling-element specimens and full-scale rolling-element bearings.
Structural Acoustic Prediction and Interior Noise Control Technology
NASA Technical Reports Server (NTRS)
Mathur, G. P.; Chin, C. L.; Simpson, M. A.; Lee, J. T.; Palumbo, Daniel L. (Technical Monitor)
2001-01-01
This report documents the results of Task 14, "Structural Acoustic Prediction and Interior Noise Control Technology". The task was to evaluate the performance of tuned foam elements (termed Smart Foam) both analytically and experimentally. Results taken from a three-dimensional finite element model of an active, tuned foam element are presented. Measurements of sound absorption and sound transmission loss were taken using the model. These results agree well with published data. Experimental performance data were taken in Boeing's Interior Noise Test Facility where 12 smart foam elements were applied to a 757 sidewall. Several configurations were tested. Noise reductions of 5-10 dB were achieved over the 200-800 Hz bandwidth of the controller. Accelerometers mounted on the panel provided a good reference for the controller. Configurations with far-field error microphones outperformed near-field cases.
Two-point method uncertainty during control and measurement of cylindrical element diameters
NASA Astrophysics Data System (ADS)
Glukhov, V. I.; Shalay, V. V.; Radev, H.
2018-04-01
The topic of the article is devoted to the urgent problem of the reliability of technical products geometric specifications measurements. The purpose of the article is to improve the quality of parts linear sizes control by the two-point measurement method. The article task is to investigate methodical extended uncertainties in measuring cylindrical element linear sizes. The investigation method is a geometric modeling of the element surfaces shape and location deviations in a rectangular coordinate system. The studies were carried out for elements of various service use, taking into account their informativeness, corresponding to the kinematic pairs classes in theoretical mechanics and the number of constrained degrees of freedom in the datum element function. Cylindrical elements with informativity of 4, 2, 1 and θ (zero) were investigated. The uncertainties estimation of in two-point measurements was made by comparing the results of of linear dimensions measurements with the functional diameters maximum and minimum of the element material. Methodical uncertainty is formed when cylindrical elements with maximum informativeness have shape deviations of the cut and the curvature types. Methodical uncertainty is formed by measuring the element average size for all types of shape deviations. The two-point measurement method cannot take into account the location deviations of a dimensional element, so its use for elements with informativeness less than the maximum creates unacceptable methodical uncertainties in measurements of the maximum, minimum and medium linear dimensions. Similar methodical uncertainties also exist in the arbitration control of the linear dimensions of the cylindrical elements by limiting two-point gauges.
Fuel assembly for nuclear reactors
Creagan, Robert J.; Frisch, Erling
1977-01-01
A new and improved fuel assembly is formed to minimize the amount of parasitic structural material wherein a plurality of hollow tubular members are juxtaposed to the fuel elements of the assembly. The tubular members may serve as guide tubes for control elements and are secured to a number of longitudinally spaced grid members along the fuel assembly. The grid members include means thereon engaging each of the fuel elements to laterally position the fuel elements in a predetermined array. Openings in the bottom of each hollow member serve as a shock absorber to cushion shock transmitted to the structure when the control elements are rapidly inserted in their corresponding tubular members.
Adaptive Distributed Intelligent Control Architecture for Future Propulsion Systems (Preprint)
2007-04-01
weight will be reduced by replacing heavy harness assemblies and FADECs , with distributed processing elements interconnected. This paper reviews...Digital Electronic Controls ( FADECs ), with distributed processing elements interconnected through a serial bus. Efficient data flow throughout the...because intelligence is embedded in components while overall control is maintained in the FADEC . The need for Distributed Control Systems in
Cai, Lei; Chen, Tianlu; Yang, Jinglei; Zhou, Kejun; Yan, Xiaomei; Chen, Wenzhong; Sun, Liya; Li, Linlin; Qin, Shengying; Wang, Peng; Yang, Ping; Cui, Donghong; Burmeister, Margit; He, Lin; Jia, Wei; Wan, Chunling
2015-10-12
Little is known about the trace element profile differences between Schizophrenia patients and healthy controls; previous studies about the association of certain elements with Schizophrenia have obtained conflicting results. To identify these differences in the Han Chinese population, inductively coupled plasma-mass spectrometry was used to quantify the levels of 35 elements in the sera of 111 Schizophrenia patients and 110 healthy participants, which consisted of a training (61/61 for cases/controls included) and a test group including remaining participants. An orthogonal projection to latent structures model was constructed from the training group (R(2)Y = 0.465, Q(2)cum = 0.343) had a sensitivity of 76.0% and a specificity of 71.4% in the test group. Single element analysis indicated that the concentrations of cesium, zinc, and selenium were significantly reduced in patients with Schizophrenia in both the training and test groups. The meta-analysis including 522 cases and 360 controls supported that Zinc was significantly associated with Schizophrenia (standardized mean difference [SMD], -0.81; 95% confidence intervals [CI], -1.46 to -0.16, P = 0.01) in the random-effect model. Information theory analysis indicated that Zinc could play roles independently in Schizophrenia. These results suggest clear element profile differences between patients with Schizophrenia and healthy controls, and reduced Zn level is confirmed in the Schizophrenia patients.
Reusable rocket engine intelligent control system framework design, phase 2
NASA Technical Reports Server (NTRS)
Nemeth, ED; Anderson, Ron; Ols, Joe; Olsasky, Mark
1991-01-01
Elements of an advanced functional framework for reusable rocket engine propulsion system control are presented for the Space Shuttle Main Engine (SSME) demonstration case. Functional elements of the baseline functional framework are defined in detail. The SSME failure modes are evaluated and specific failure modes identified for inclusion in the advanced functional framework diagnostic system. Active control of the SSME start transient is investigated, leading to the identification of a promising approach to mitigating start transient excursions. Key elements of the functional framework are simulated and demonstration cases are provided. Finally, the advanced function framework for control of reusable rocket engines is presented.
Subwavelength nonlinear phase control and anomalous phase matching in plasmonic metasurfaces
NASA Astrophysics Data System (ADS)
Almeida, Euclides; Shalem, Guy; Prior, Yehiam
2016-01-01
Metasurfaces, and in particular those containing plasmonic-based metallic elements, constitute an attractive set of materials with a potential for replacing standard bulky optical elements. In recent years, increasing attention has been focused on their nonlinear optical properties, particularly in the context of second and third harmonic generation and beam steering by phase gratings. Here, we harness the full phase control enabled by subwavelength plasmonic elements to demonstrate a unique metasurface phase matching that is required for efficient nonlinear processes. We discuss the difference between scattering by a grating and by subwavelength phase-gradient elements. We show that for such interfaces an anomalous phase-matching condition prevails, which is the nonlinear analogue of the generalized Snell's law. The subwavelength phase control of optical nonlinearities paves the way for the design of ultrathin, flat nonlinear optical elements. We demonstrate nonlinear metasurface lenses, which act both as generators and as manipulators of the frequency-converted signal.
Medical catheters thermally manipulated by fiber optic bundles
Chastagner, Philippe
1992-01-01
A maneuverable medical catheter comprising a flexible tube having a functional tip. The catheter is connected to a control source. The functional tip of the catheter carries a plurality of temperature activated elements arranged in parallel and disposed about the functional tip and held in spaced relation at each end. These elements expand when they are heated. A plurality of fiber optic bundles, each bundle having a proximal end attached to the control source and a distal end attached to one of the elements carry light into the elements where the light is absorbed as heat. By varying the optic fiber that is carrying the light and the intensity of the light, the bending of the elements can be controlled and thus the catheter steered. In an alternate embodiment, the catheter carries a medical instrument for gathering a sample of tissue. The instrument may also be deployed and operated by thermal expansion and contraction of its moving parts.
Trace elements and diabetes: Assessment of levels in tears and serum.
Cancarini, A; Fostinelli, J; Napoli, L; Gilberti, M E; Apostoli, P; Semeraro, F
2017-01-01
Tear film is critical for the well-being and homeostasis of the ocular surface. Although the composition of the tear film is well known, the composition of metallic elements have yet to be analysed. Despite trace elements metabolism has been reported to play a role in the pathogenesis of diabetes mellitus, a metabolic disease that affects several aspects of homeostasis, little is known in the literature regarding concentration and possible variation of metallic elements in tear film. We studied the concentrations of several essential and non-essential metallic elements in the tear fluid and serum of patients with type II diabetes mellitus and a group of non-diabetic controls. Serum and tear fluid were collected from 97 patients: 47 type II diabetic patients and 50 non-diabetic controls. Regarding tear film, there were statistically significant differences in Zinc, Chrome, Cobalt, Manganese, Barium, and Lead between groups; the values of all metallic elements were found to be statistically significant higher in patients with mellitus type II diabetes. Regarding serum values there was a statistically significant difference in Chrome, Cobalt, and Selenium values; the concentrations of Chrome and Cobalt were higher in the control group, while Selenium concentration was higher in diabetic patients. In patients with type II diabetes, metal elements with higher concentrations in tears compared to serum were: Lead, Barium, Manganese, Cobalt, and Chrome. In the control group, the metal elements with the highest concentration in tear film compared to serum were Chrome, Manganese, Barium, and Lead. In this study, we attempted to evaluate the possible effect of a disease, such as diabetes, on the metabolism of metallic elements. Although our evidence was very interesting, it is probably limited in its accuracy due to the fact that individuals in the control group harboured ocular pathologies. This work lays the foundation for future studies. Copyright © 2016 Elsevier Ltd. All rights reserved.
2013-09-01
control GCE ground combat element LCE logistics combat element MAGTF Marine Air Ground Task Force MWCS Marine Wing Communications Squadron NPS Naval...elements: command element (CE), ground combat el- ement ( GCE ), aviation combat element (ACE), and logistics combat element (LCE). Each ele- ment...This layer provides unimpeded high-speed connectivity between remote sites and the Internet. Limited security policies are applied at this level to
Trace element control in binary Ni-25Cr and ternary Ni-30Co-30Cr master alloy castings
DOE Office of Scientific and Technical Information (OSTI.GOV)
Detrois, Martin; Jablonski, Paul D.
Electro-slag remelting (ESR) is used for control of unwanted elements in commercial alloys. This study focuses on master alloys of Ni-25Cr and Ni-30Co-30Cr, processed through a combination of vacuum induction melting (VIM) and electro-slag remelting (ESR). Minor additions were made to control tramp element levels and modify the melting characteristics. Nitrogen and sulfur levels below 10 ppm and oxygen levels below 100 ppm were obtained in the final products. The role of the alloy additions in lowering the tramp element content, the resulting residual inclusions and the melting characteristics were determined computationally and confirmed experimentally. Additions of titanium were beneficialmore » to the control of oxygen levels during VIM and nitrogen levels during ESR. Aluminum additions helped to control oxygen levels during remelting, however, aluminum pickup occurred when excess titanium was present during ESR. The usefulness of these master alloys for use as experimental remelt stock will also be discussed.« less
NASA Astrophysics Data System (ADS)
Yang, Li; Wang, Ye; Liu, Huikai; Yan, Guanghui; Kou, Wei
2014-11-01
The components overheating inside an object, such as inside an electric control cabinet, a moving object, and a running machine, can easily lead to equipment failure or fire accident. The infrared remote sensing method is used to inspect the surface temperature of object to identify the overheating components inside the object in recent years. It has important practical application of using infrared thermal imaging surface temperature measurement to identify the internal overheating elements inside an electric control cabinet. In this paper, through the establishment of test bench of electric control cabinet, the experimental study was conducted on the inverse identification technology of internal overheating components inside an electric control cabinet using infrared thermal imaging. The heat transfer model of electric control cabinet was built, and the temperature distribution of electric control cabinet with internal overheating element is simulated using the finite volume method (FVM). The outer surface temperature of electric control cabinet was measured using the infrared thermal imager. Combining the computer image processing technology and infrared temperature measurement, the surface temperature distribution of electric control cabinet was extracted, and using the identification algorithm of inverse heat transfer problem (IHTP) the position and temperature of internal overheating element were identified. The results obtained show that for single element overheating inside the electric control cabinet the identifying errors of the temperature and position were 2.11% and 5.32%. For multiple elements overheating inside the electric control cabinet the identifying errors of the temperature and positions were 3.28% and 15.63%. The feasibility and effectiveness of the method of IHTP and the correctness of identification algorithm of FVM were validated.
Parallel array of independent thermostats for column separations
Foret, Frantisek; Karger, Barry L.
2005-08-16
A thermostat array including an array of two or more capillary columns (10) or two or more channels in a microfabricated device is disclosed. A heat conductive material (12) surrounded each individual column or channel in array, each individual column or channel being thermally insulated from every other individual column or channel. One or more independently controlled heating or cooling elements (14) is positioned adjacent to individual columns or channels within the heat conductive material, each heating or cooling element being connected to a source of heating or cooling, and one or more independently controlled temperature sensing elements (16) is positioned adjacent to the individual columns or channels within the heat conductive material. Each temperature sensing element is connected to a temperature controller.
Choi, Rihwa; Kim, Hyoung-Tae; Lim, Yaeji; Kim, Min-Ji; Kwon, O Jung; Jeon, Kyeongman; Park, Hye Yun; Jeong, Byeong-Ho; Koh, Won-Jung; Lee, Soo-Youn
2015-01-01
Deficiencies in essential trace elements are associated with impaired immunity in tuberculosis infection. However, the trace element concentrations in the serum of Korean patients with tuberculosis have not yet been investigated. This study aimed to compare the serum trace element concentrations of Korean adult patients with tuberculosis with noninfected controls and to assess the impact of serum trace element concentration on clinical outcome after antituberculosis treatment. The serum concentrations of four trace elements in 141 consecutively recruited patients with tuberculosis and 79 controls were analyzed by inductively coupled plasma-mass spectrometry. Demographic characteristics were also analyzed. Serum cobalt and copper concentrations were significantly higher in patients with tuberculosis compared with controls, while zinc and selenium concentrations were significantly lower (p < 0.01). Moreover, serum selenium and zinc concentrations were positively correlated (ρ = 0.41, p < 0.05). A high serum copper concentration was associated with a worse clinical outcome, as assessed after one month of antituberculosis therapy. Specifically, culture-positive patients had higher serum copper concentrations than culture-negative patients (p < 0.05). Patients with tuberculosis had altered serum trace element concentrations. Further research is needed to elucidate the roles of individual trace elements and to determine their clinical impact on patients with tuberculosis. PMID:26197334
Elemental Impurities in Pharmaceutical Excipients.
Li, Gang; Schoneker, Dave; Ulman, Katherine L; Sturm, Jason J; Thackery, Lisa M; Kauffman, John F
2015-12-01
Control of elemental impurities in pharmaceutical materials is currently undergoing a transition from control based on concentrations in components of drug products to control based on permitted daily exposures in drug products. Within the pharmaceutical community, there is uncertainty regarding the impact of these changes on manufactures of drug products. This uncertainty is fueled in part by a lack of publically available information on elemental impurity levels in common pharmaceutical excipients. This paper summarizes a recent survey of elemental impurity levels in common pharmaceutical excipients as well as some drug substances. A widely applicable analytical procedure was developed and was shown to be suitable for analysis of elements that are subject to United States Pharmacopoeia Chapter <232> and International Conference on Harmonization's Q3D Guideline on Elemental Impurities. The procedure utilizes microwave-assisted digestion of pharmaceutical materials and inductively coupled plasma mass spectrometry for quantitative analysis of these elements. The procedure was applied to 190 samples from 31 different excipients and 15 samples from eight drug substances provided through the International Pharmaceutical Excipient Council of the Americas. The results of the survey indicate that, for the materials included in the study, relatively low levels of elemental impurities are present. © 2015 The Authors. Journal of Pharmaceutical Sciences published by Wiley Periodicals, Inc. and the American Pharmacists Association.
Case studies of power and control related to tobacco use during pregnancy.
Greaves, Lorraine; Kalaw, Cecilia; Bottorff, Joan L
2007-01-01
The objective was to identify and describe elements of power and control evident in couple tobacco-related interaction patterns during pregnancy. Using a case study approach, elements of the Duluth Abuse Intervention Project Power and Control Wheel were used to examine women's experiences of tobacco reduction during pregnancy and post partum. Three cases were selected from a larger qualitative sample, using a maximum variation sampling approach. Although no direct evidence of partner abuse or violence accompanying partner efforts to influence women's smoking was described, most of the elements of power and control were present in the case study, and appeared to cause an emotional toll and a negative impact on women's ability to freely express their views about their own tobacco use. Elements of power and control, however subtle, are potentially important and unrecognized dimensions of women's tobacco reduction experiences. Additional care and attention should be taken in designing tobacco reduction interventions and policies directed at pregnant and post partum women and their partners to reduce the possibility that these interventions may contribute to the use of power and control.
Nagle, Aniket; Riener, Robert; Wolf, Peter
2015-01-01
Computer games are increasingly being used for training cognitive functions like working memory and attention among the growing population of older adults. While cognitive training games often include elements like difficulty adaptation, rewards, and visual themes to make the games more enjoyable and effective, the effect of different degrees of afforded user control in manipulating these elements has not been systematically studied. To address this issue, two distinct implementations of the three aforementioned game elements were tested among healthy older adults (N = 21, 69.9 ± 6.4 years old) playing a game-like version of the n-back task on a tablet at home for 3 weeks. Two modes were considered, differentiated by the afforded degree of user control of the three elements: user control of difficulty vs. automatic difficulty adaptation, difficulty-dependent rewards vs. automatic feedback messages, and user choice of visual theme vs. no choice. The two modes ("USER-CONTROL" and "AUTO") were compared for frequency of play, duration of play, and in-game performance. Participants were free to play the game whenever and for however long they wished. Participants in USER-CONTROL exhibited significantly higher frequency of playing, total play duration, and in-game performance than participants in AUTO. The results of the present study demonstrate the efficacy of providing user control in the three game elements, while validating a home-based study design in which participants were not bound by any training regimen, and could play the game whenever they wished. The results have implications for designing cognitive training games that elicit higher compliance and better in-game performance, with an emphasis on home-based training.
Method and system for downhole clock synchronization
Hall, David R.; Bartholomew, David B.; Johnson, Monte; Moon, Justin; Koehler, Roger O.
2006-11-28
A method and system for use in synchronizing at least two clocks in a downhole network are disclosed. The method comprises determining a total signal latency between a controlling processing element and at least one downhole processing element in a downhole network and sending a synchronizing time over the downhole network to the at least one downhole processing element adjusted for the signal latency. Electronic time stamps may be used to measure latency between processing elements. A system for electrically synchronizing at least two clocks connected to a downhole network comprises a controlling processing element connected to a synchronizing clock in communication over a downhole network with at least one downhole processing element comprising at least one downhole clock. Preferably, the downhole network is integrated into a downhole tool string.
High temperature electrically conducting ceramic heating element and control system
NASA Technical Reports Server (NTRS)
Halbach, C. R.; Page, R. J.
1975-01-01
Improvements were made in both electrode technology and ceramic conductor quality to increase significantly the lifetime and thermal cycling capability of electrically conducting ceramic heater elements. These elements were operated in vacuum, inert and reducing environments as well as oxidizing atmospheres adding to the versatility of the conducting ceramic as an ohmic heater. Using stabilized zirconia conducting ceramic heater elements, a furnace was fabricated and demonstrated to have excellent thermal response and cycling capability. The furnace was used to melt platinum-20% rhodium alloy (melting point 1904 C) with an isothermal ceramic heating element having a nominal working cavity size of 2.5 cm diameter by 10.0 cm long. The furnace was operated to 1940 C with the isothermal ceramic heating element. The same furnace structure was fitted with a pair of main heater elements to provide axial gradient temperature control over a working cavity length of 17.8 cm.
Process for synthesizing compounds from elemental powders and product
Rabin, B.H.; Wright, R.N.
1993-12-14
A process for synthesizing intermetallic compounds from elemental powders is described. The elemental powders are initially combined in a ratio which approximates the stoichiometric composition of the intermetallic compound. The mixed powders are then formed into a compact which is heat treated at a controlled rate of heating such that an exothermic reaction between the elements is initiated. The heat treatment may be performed under controlled conditions ranging from a vacuum (pressureless sintering) to compression (hot pressing) to produce a desired densification of the intermetallic compound. In a preferred form of the invention, elemental powders of Fe and Al are combined to form aluminide compounds of Fe[sub 3] Al and FeAl. 25 figures.
Process for synthesizing compounds from elemental powders and product
Rabin, Barry H.; Wright, Richard N.
1993-01-01
A process for synthesizing intermetallic compounds from elemental powders. The elemental powders are initially combined in a ratio which approximates the stoichiometric composition of the intermetallic compound. The mixed powders are then formed into a compact which is heat treated at a controlled rate of heating such that an exothermic reaction between the elements is initiated. The heat treatment may be performed under controlled conditions ranging from a vacuum (pressureless sintering) to compression (hot pressing) to produce a desired densification of the intermetallic compound. In a preferred form of the invention, elemental powders of Fe and Al are combined to form aluminide compounds of Fe.sub.3 Al and FeAl.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Carlson, C.L.; Adriano, D.C.
Differences in aboveground tissue concentrations of trace elements were assessed for sweetgum (Liquidambar styraciflua L.) and sycamore (Plantanus occidentalis L.) growing on two abandoned coal fly ash basins and a control soil. The wet basin (pH = 5.58) had originally received precipitator ash in an ash-water slurry, while the dry basin (pH = 8.26) had received both precipitator and bottom ash in dry form. In general, trees from the wet basin exhibited elevated trace element concentrations in comparison to the controls, while the dry basin trees exhibited reduced concentrations. On eof the most striking differenced in elemental concentrations among themore » ash basin and control trees was observed for Mn, with the control trees exhibiting concentrations orders of magnitude greater than the ash basin trees. Differences in foliar trace element concentrations among the sites can generally be explained by differences in substrate trace element concentrations and/or substrate pH. While trees from the wet ash basin generally had the highest trace element concentrations, these trees also attained the greatest height and diameter growth, suggesting that the elevated trace element concentrations in the wet basin substrate are not limiting the establishment of these two species. The greater height and diameter growth of the wet basin trees is presumably a result of the greater water-holding capacity of the substrate on this site. Differences in growth and tissue concentrations between sweetgum and sycamore highlight the importance of using more than one species when assessing metal toxicity or deficiency on a given substrate.« less
Abnormal dynamics of language in schizophrenia.
Stephane, Massoud; Kuskowski, Michael; Gundel, Jeanette
2014-05-30
Language could be conceptualized as a dynamic system that includes multiple interactive levels (sub-lexical, lexical, sentence, and discourse) and components (phonology, semantics, and syntax). In schizophrenia, abnormalities are observed at all language elements (levels and components) but the dynamic between these elements remains unclear. We hypothesize that the dynamics between language elements in schizophrenia is abnormal and explore how this dynamic is altered. We, first, investigated language elements with comparable procedures in patients and healthy controls. Second, using measures of reaction time, we performed multiple linear regression analyses to evaluate the inter-relationships among language elements and the effect of group on these relationships. Patients significantly differed from controls with respect to sub-lexical/lexical, lexical/sentence, and sentence/discourse regression coefficients. The intercepts of the regression slopes increased in the same order above (from lower to higher levels) in patients but not in controls. Regression coefficients between syntax and both sentence level and discourse level semantics did not differentiate patients from controls. This study indicates that the dynamics between language elements is abnormal in schizophrenia. In patients, top-down flow of linguistic information might be reduced, and the relationship between phonology and semantics but not between syntax and semantics appears to be altered. Published by Elsevier Ireland Ltd.
NASA Technical Reports Server (NTRS)
Fijany, Amir (Inventor); Bejczy, Antal K. (Inventor)
1994-01-01
In a computer having a large number of single-instruction multiple data (SIMD) processors, each of the SIMD processors has two sets of three individual processor elements controlled by a master control unit and interconnected among a plurality of register file units where data is stored. The register files input and output data in synchronism with a minor cycle clock under control of two slave control units controlling the register file units connected to respective ones of the two sets of processor elements. Depending upon which ones of the register file units are enabled to store or transmit data during a particular minor clock cycle, the processor elements within an SIMD processor are connected in rings or in pipeline arrays, and may exchange data with the internal bus or with neighboring SIMD processors through interface units controlled by respective ones of the two slave control units.
Adaptive Process Control with Fuzzy Logic and Genetic Algorithms
NASA Technical Reports Server (NTRS)
Karr, C. L.
1993-01-01
Researchers at the U.S. Bureau of Mines have developed adaptive process control systems in which genetic algorithms (GA's) are used to augment fuzzy logic controllers (FLC's). GA's are search algorithms that rapidly locate near-optimum solutions to a wide spectrum of problems by modeling the search procedures of natural genetics. FLC's are rule based systems that efficiently manipulate a problem environment by modeling the 'rule-of-thumb' strategy used in human decision-making. Together, GA's and FLC's possess the capabilities necessary to produce powerful, efficient, and robust adaptive control systems. To perform efficiently, such control systems require a control element to manipulate the problem environment, an analysis element to recognize changes in the problem environment, and a learning element to adjust to the changes in the problem environment. Details of an overall adaptive control system are discussed. A specific laboratory acid-base pH system is used to demonstrate the ideas presented.
Genetic algorithms in adaptive fuzzy control
NASA Technical Reports Server (NTRS)
Karr, C. Lucas; Harper, Tony R.
1992-01-01
Researchers at the U.S. Bureau of Mines have developed adaptive process control systems in which genetic algorithms (GA's) are used to augment fuzzy logic controllers (FLC's). GA's are search algorithms that rapidly locate near-optimum solutions to a wide spectrum of problems by modeling the search procedures of natural genetics. FLC's are rule based systems that efficiently manipulate a problem environment by modeling the 'rule-of-thumb' strategy used in human decision making. Together, GA's and FLC's possess the capabilities necessary to produce powerful, efficient, and robust adaptive control systems. To perform efficiently, such control systems require a control element to manipulate the problem environment, an analysis element to recognize changes in the problem environment, and a learning element to adjust fuzzy membership functions in response to the changes in the problem environment. Details of an overall adaptive control system are discussed. A specific computer-simulated chemical system is used to demonstrate the ideas presented.
A rationale for human operator pulsive control behavior
NASA Technical Reports Server (NTRS)
Hess, R. A.
1979-01-01
When performing tracking tasks which involve demanding controlled elements such as those with K/s-squared dynamics, the human operator often develops discrete or pulsive control outputs. A dual-loop model of the human operator is discussed, the dominant adaptive feature of which is the explicit appearance of an internal model of the manipulator-controlled element dynamics in an inner feedback loop. Using this model, a rationale for pulsive control behavior is offered which is based upon the assumption that the human attempts to reduce the computational burden associated with time integration of sensory inputs. It is shown that such time integration is a natural consequence of having an internal representation of the K/s-squared-controlled element dynamics in the dual-loop model. A digital simulation is discussed in which a modified form of the dual-loop model is shown to be capable of producing pulsive control behavior qualitively comparable to that obtained in experiment.
Schmidt, Thomas; McCabe, Bernadette K; Harris, Peter W; Lee, Seonmi
2018-05-18
In this study, anaerobic digestion of slaughterhouse wastewater with the addition of trace elements was monitored for biogas quantity, quality and process stability using CSTR digesters operated at mesophilic temperature. The determination of trace element concentrations was shown to be deficient in Fe, Ni, Co, Mn and Mo compared to recommendations given in the literature. Addition of these trace elements resulted in enhanced degradation efficiency, higher biogas production and improved process stability. Higher organic loading rates and lower hydraulic retention times were achieved in comparison to the control digesters. A critical accumulation of volatile fatty acids was observed at an organic loading rate of 1.82 g L -1 d -1 in the control compared to 2.36 g L -1 d -1 in the digesters with trace element addition. The improved process stability was evident in the final weeks of experimentation, in which control reactors produced 84% less biogas per day compared to the reactors containing trace elements. Copyright © 2018 Elsevier Ltd. All rights reserved.
Static shape control for adaptive wings
NASA Astrophysics Data System (ADS)
Austin, Fred; Rossi, Michael J.; van Nostrand, William; Knowles, Gareth; Jameson, Antony
1994-09-01
A theoretical method was developed and experimentally validated, to control the static shape of flexible structures by employing internal translational actuators. A finite element model of the structure, without the actuators present, is employed to obtain the multiple-input, multiple-output control-system gain matrices for actuator-load control as well as actuator-displacement control. The method is applied to the quasistatic problem of maintaining an optimum-wing cross section during various transonic-cruise flight conditions to obtain significant reductions in the shock-induced drag. Only small, potentially achievable, adaptive modifications to the profile are required. The adaptive-wing concept employs actuators as truss elements of active ribs to reshape the wing cross section by deforming the structure. Finite element analyses of an adaptive-rib model verify the controlled-structure theory. Experiments on the model were conducted, and arbitrarily selected deformed shapes were accurately achieved.
NASA Technical Reports Server (NTRS)
Weiss, Jerold L.; Hsu, John Y.
1986-01-01
The use of a decentralized approach to failure detection and isolation for use in restructurable control systems is examined. This work has produced: (1) A method for evaluating fundamental limits to FDI performance; (2) Application using flight recorded data; (3) A working control element FDI system with maximal sensitivity to critical control element failures; (4) Extensive testing on realistic simulations; and (5) A detailed design methodology involving parameter optimization (with respect to model uncertainties) and sensitivity analyses. This project has concentrated on detection and isolation of generic control element failures since these failures frequently lead to emergency conditions and since knowledge of remaining control authority is essential for control system redesign. The failures are generic in the sense that no temporal failure signature information was assumed. Thus, various forms of functional failures are treated in a unified fashion. Such a treatment results in a robust FDI system (i.e., one that covers all failure modes) but sacrifices some performance when detailed failure signature information is known, useful, and employed properly. It was assumed throughout that all sensors are validated (i.e., contain only in-spec errors) and that only the first failure of a single control element needs to be detected and isolated. The FDI system which has been developed will handle a class of multiple failures.
Gemas: issues from the comparison of aqua regia and X-ray fluorescence results
NASA Astrophysics Data System (ADS)
Dinelli, Enrico; Birke, Manfred; Reimann, Clemens; Demetriades, Alecos; DeVivo, Benedetto; Flight, Dee; Ladenberger, Anna; Albanese, Stefano; Cicchella, Domenico; Lima, Annamaria
2014-05-01
The comparison of analytical results from aqua regia (AR) and X-ray fluorescence spectroscopy (XRF) can provide information on soil processes controlling the element distribution. The GEMAS (GEochemical Mapping of Agricultural and grazing land Soils) agricultural soil database is used for this comparison. Analyses for the same suite of elements and parameters were carried out in the same laboratory under strict quality control procedures. Sample preparation has been conducted at the laboratory of the The comparison of analytical results from aqua regia (AR) and X-ray fluorescence spectroscopy (XRF) can provide information on soil processes controlling the element distribution in soil. The GEMAS (GEochemical Mapping of Agricultural and grazing land Soils) agricultural soil database, consisting of 2 x ca. 2100 samples spread evenly over 33 European countries, is used for this comparison. Analyses for the same suite of elements and parameters were carried out in the same laboratory under strict quality control procedures. Sample preparation has been conducted at the laboratory of the Geological Survey of the Slovak Republic, AR analyses were carried out at ACME Labs, and XRF analyses at the Federal Institute for Geosciences and Natural Resources, Germany Element recovery by AR is very different, ranging from <1% (e.g. Na, Zr) to > 80% (e.g. Mn, P, Co). Recovery is controlled by mineralogy of the parent material, but geographic and climatic factors and the weathering history of the soils are also important. Nonetheless, even the very low recovery elements show wide ranges of variation and spatial patterns that are affected by other factors than soil parent material. For many elements soil pH have a clear influence on AR extractability: under acidic soil conditions almost all elements tend to be leached and their extractability is generally low. It progressively increases with increasing pH and is highest in the pH range 7-8. Critical is the clay content of the soil that almost for all elements correspond to higher extractability with increasing clay abundance. Also other factors such as organic matter content of soil, Fe and Mn occurrence are important for certain elements or in selected areas. This work illustrates that there are significant differences in the extractability of elements from soils and addresses important influencing factors related to soil properties, geology, climate.
Status of essential elements in autism spectrum disorder: systematic review and meta-analysis.
Saghazadeh, Amene; Ahangari, Narges; Hendi, Kasra; Saleh, Fatemeh; Rezaei, Nima
2017-10-26
Autism spectrum disorder (ASD) is a lifelong neurodevelopmental disorder that imposes heavy financial burden on governments and families of affected children. It is considered a multifactorial condition, where trace elements are among environmental factors that may contribute to ASD. Meanwhile, the between-study variance is high. The present systematic review was designed to investigate the difference in trace element measures between patients with ASD and control subjects. Meta-analyses showed that the hair concentrations of chromium (p=0.024), cobalt (p=0.012), iodine (p=0.000), iron (p=0.017), and magnesium (p=0.007) in ASD patients were significantly lower than those of control subjects, while there were higher magnesium levels in the hair of ASD patients compared to that of controls (p=0.010). Patients with ASD had higher blood levels of copper (p=0.000) and lower levels of zinc compared to controls (p=0.021). Further urinary iodine levels in patients with ASD were decreased in comparison with controls (p=0.026). Sensitivity analyses showed that ASD patients in non-Asian but not in Asian countries had lower hair concentrations of chromium compared to controls. Also, such analyses indicated that ASD patients in Asian countries had lower hair zinc concentrations, whereas ASD patients in non-Asian countries had higher hair zinc concentrations in comparison with control subjects. This study found significant differences in the content of trace elements between patients with ASD compared to controls. The findings help highlighting the role of trace elements as environmental factors in the etiology of ASD.
Solar electric propulsion thrust subsystem development
NASA Technical Reports Server (NTRS)
Masek, T. D.
1973-01-01
The Solar Electric Propulsion System developed under this program was designed to demonstrate all the thrust subsystem functions needed on an unmanned planetary vehicle. The demonstration included operation of the basic elements, power matching input and output voltage regulation, three-axis thrust vector control, subsystem automatic control including failure detection and correction capability (using a PDP-11 computer), operation of critical elements in thermal-vacuum-, zero-gravity-type propellant storage, and data outputs from all subsystem elements. The subsystem elements, functions, unique features, and test setup are described. General features and capabilities of the test-support data system are also presented. The test program culminated in a 1500-h computer-controlled, system-functional demonstration. This included simultaneous operation of two thruster/power conditioner sets. The results of this testing phase satisfied all the program goals.
Diffusion of Siderophile Elements in Fe Metal: Application to Zoned Metal Grains in Chondrites
NASA Technical Reports Server (NTRS)
Righter, K.; Campbell, A. J.; Humajun, M.
2003-01-01
The distribution of highly siderophile elements (HSE) in planetary materials is controlled mainly by metal. Diffusion processes can control the distribution or re-distribution of these elements within metals, yet there is little systematic or appropriate diffusion data that can be used to interpret HSE concentrations in such metals. Because our understanding of isotope chronometry, redox processes, kamacite/taenite-based cooling rates, and metal grain zoning would be enhanced with diffusion data, we have measured diffusion coefficients for Ni, Co, Ga, Ge, Ru, Pd, Ir and Au in Fe metal from 1200 to 1400 C and 1 bar and 10 kbar. These new data on refractory and volatile siderophile elements are used to evaluate the role of diffusional processes in controlling zoning patterns in metal-rich chondrites.
Long-Range Control of Gene Expression: Emerging Mechanisms and Disruption in Disease
Kleinjan, Dirk A.; van Heyningen, Veronica
2005-01-01
Transcriptional control is a major mechanism for regulating gene expression. The complex machinery required to effect this control is still emerging from functional and evolutionary analysis of genomic architecture. In addition to the promoter, many other regulatory elements are required for spatiotemporally and quantitatively correct gene expression. Enhancer and repressor elements may reside in introns or up- and downstream of the transcription unit. For some genes with highly complex expression patterns—often those that function as key developmental control genes—the cis-regulatory domain can extend long distances outside the transcription unit. Some of the earliest hints of this came from disease-associated chromosomal breaks positioned well outside the relevant gene. With the availability of wide-ranging genome sequence comparisons, strong conservation of many noncoding regions became obvious. Functional studies have shown many of these conserved sites to be transcriptional regulatory elements that sometimes reside inside unrelated neighboring genes. Such sequence-conserved elements generally harbor sites for tissue-specific DNA-binding proteins. Developmentally variable chromatin conformation can control protein access to these sites and can regulate transcription. Disruption of these finely tuned mechanisms can cause disease. Some regulatory element mutations will be associated with phenotypes distinct from any identified for coding-region mutations. PMID:15549674
Manufacturing processes for fabricating graphite/PMR 15 polyimide structural elements
NASA Technical Reports Server (NTRS)
Sheppard, C. H.; Hoggatt, J. T.; Symonds, W. A.
1979-01-01
Investigations were conducted to obtain commercially available graphite/PMR-15 polyimide prepreg, develop an autoclave manufacturing process, and demonstrate the process by manufacturing structural elements. Controls were established on polymer, prepreg, composite fabrication, and quality assurance, Successful material quality control and processes were demonstrated by fabricating major structural elements including flat laminates, hat sections, I beam sections, honeycomb sandwich structures, and molded graphite reinforced fittings. Successful fabrication of structural elements and simulated section of the space shuttle aft body flap shows that the graphite/PMR-15 polyimide system and the developed processes are ready for further evaluation in flight test hardware.
Compensation for electrical converter nonlinearities
Perisic, Milun; Ransom, Ray M; Kajouke, Lateef A
2013-11-19
Systems and methods are provided for delivering energy from an input interface to an output interface. An electrical system includes an input interface, an output interface, an energy conversion module between the input interface and the output interface, an inductive element between the input interface and the energy conversion module, and a control module. The control module determines a compensated duty cycle control value for operating the energy conversion module to produce a desired voltage at the output interface and operates the energy conversion module to deliver energy to the output interface with a duty cycle that is influenced by the compensated duty cycle control value. The compensated duty cycle control value is influenced by the current through the inductive element and accounts for voltage across the switching elements of the energy conversion module.
49 CFR 236.576 - Roadway element.
Code of Federal Regulations, 2013 CFR
2013-10-01
... 49 Transportation 4 2013-10-01 2013-10-01 false Roadway element. 236.576 Section 236.576..., Train Control and Cab Signal Systems Inspection and Tests; Roadway § 236.576 Roadway element. Roadway elements, except track circuits, including those for test purposes, shall be gaged monthly for height and...
49 CFR 236.576 - Roadway element.
Code of Federal Regulations, 2014 CFR
2014-10-01
... 49 Transportation 4 2014-10-01 2014-10-01 false Roadway element. 236.576 Section 236.576..., Train Control and Cab Signal Systems Inspection and Tests; Roadway § 236.576 Roadway element. Roadway elements, except track circuits, including those for test purposes, shall be gaged monthly for height and...
49 CFR 236.576 - Roadway element.
Code of Federal Regulations, 2012 CFR
2012-10-01
... 49 Transportation 4 2012-10-01 2012-10-01 false Roadway element. 236.576 Section 236.576..., Train Control and Cab Signal Systems Inspection and Tests; Roadway § 236.576 Roadway element. Roadway elements, except track circuits, including those for test purposes, shall be gaged monthly for height and...
Microwave waveguide manifold and method
Staehlin, John H.
1987-01-01
A controllably electrically coupled, physically intersecting plural waveguide manifold assembly wherein the intersecting waveguide elements are fabricated in integral unitary relationship from a single piece of metal in order to avoid the inaccuracies and difficult-to-control fabrication steps associated with uniting separate waveguide elements into a unitary structure. An X-band aluminum airborne radar manifold example is disclosed, along with a fabrication sequence for the manifold and the electrical energy communicating apertures joining the manifold elements.
Microwave waveguide manifold and method
Staehlin, John H.
1987-12-01
A controllably electrically coupled, physically intersecting plural waveguide manifold assembly wherein the intersecting waveguide elements are fabricated in integral unitary relationship from a single piece of metal in order to avoid the inaccuracies and difficult-to-control fabrication steps associated with uniting separate waveguide elements into a unitary structure. An X-band aluminum airborne radar manifold example is disclosed, along with a fabrication sequence for the manifold and the electrical energy communicating apertures joining the manifold elements.
Treshow, M.
1958-08-19
A neuclear reactor is described of the heterogeneous type and employing replaceable tubular fuel elements and heavy water as a coolant and moderator. A pluraltty of fuel tubesa having their axes parallel, extend through a tank type pressure vessel which contatns the liquid moderator. The fuel elements are disposed within the fuel tubes in the reaetive portion of the pressure vessel during normal operation and the fuel tubes have removable plug members at each end to permit charging and discharging of the fuel elements. The fuel elements are cylindrical strands of jacketed fissionable material having helical exterior ribs. A bundle of fuel elements are held within each fuel tube with their longitudinal axes parallel, the ribs serving to space them apart along their lengths. Coolant liquid is circulated through the fuel tubes between the spaced fuel elements. Suitable control rod and monitoring means are provided for controlling the reactor.
Code of Federal Regulations, 2010 CFR
2010-07-01
.... Auxiliary emission control device (AECD) means any element of design which senses temperature, locomotive... those devices, systems or elements of design which control or reduce the emission of substances from an... Equivalent means the sum of the carbon mass contributions of non-oxygenated hydrocarbons, alcohols and...
Code of Federal Regulations, 2011 CFR
2011-07-01
.... Auxiliary emission control device (AECD) means any element of design which senses temperature, locomotive... those devices, systems or elements of design which control or reduce the emission of substances from an... Equivalent means the sum of the carbon mass contributions of non-oxygenated hydrocarbons, alcohols and...
Code of Federal Regulations, 2013 CFR
2013-07-01
.... Auxiliary emission control device (AECD) means any element of design which senses temperature, locomotive... those devices, systems or elements of design which control or reduce the emission of substances from an... Equivalent means the sum of the carbon mass contributions of non-oxygenated hydrocarbons, alcohols and...
Code of Federal Regulations, 2014 CFR
2014-07-01
... emission control device (AECD) means any element of design which senses temperature, vessel speed, engine... means those devices, systems or elements of design which control or reduce the emission of substances.... Total Hydrocarbon Equivalent means the sum of the carbon mass contributions of non-oxygenated...
Code of Federal Regulations, 2012 CFR
2012-07-01
... emission control device (AECD) means any element of design which senses temperature, vessel speed, engine... means those devices, systems or elements of design which control or reduce the emission of substances.... Total Hydrocarbon Equivalent means the sum of the carbon mass contributions of non-oxygenated...
Code of Federal Regulations, 2013 CFR
2013-07-01
... emission control device (AECD) means any element of design which senses temperature, vessel speed, engine... means those devices, systems or elements of design which control or reduce the emission of substances.... Total Hydrocarbon Equivalent means the sum of the carbon mass contributions of non-oxygenated...
Code of Federal Regulations, 2014 CFR
2014-07-01
.... Auxiliary emission control device (AECD) means any element of design which senses temperature, locomotive... those devices, systems or elements of design which control or reduce the emission of substances from an... Equivalent means the sum of the carbon mass contributions of non-oxygenated hydrocarbons, alcohols and...
Code of Federal Regulations, 2010 CFR
2010-07-01
... emission control device (AECD) means any element of design which senses temperature, vessel speed, engine... means those devices, systems or elements of design which control or reduce the emission of substances.... Total Hydrocarbon Equivalent means the sum of the carbon mass contributions of non-oxygenated...
Code of Federal Regulations, 2012 CFR
2012-07-01
.... Auxiliary emission control device (AECD) means any element of design which senses temperature, locomotive... those devices, systems or elements of design which control or reduce the emission of substances from an... Equivalent means the sum of the carbon mass contributions of non-oxygenated hydrocarbons, alcohols and...
Code of Federal Regulations, 2011 CFR
2011-07-01
... emission control device (AECD) means any element of design which senses temperature, vessel speed, engine... means those devices, systems or elements of design which control or reduce the emission of substances.... Total Hydrocarbon Equivalent means the sum of the carbon mass contributions of non-oxygenated...
Inductively heated particulate matter filter regeneration control system
Gonze, Eugene V; Paratore Jr., Michael J; Kirby, Kevin W; Phelps, Amanda; Gregoire, Daniel J
2012-10-23
A system includes a particulate matter (PM) filter with an upstream end for receiving exhaust gas, a downstream end and zones. The system also includes a heating element. A control module selectively activates the heating element to inductively heat one of the zones.
Trajectory Control and Optimization for Responsive Spacecraft
2012-03-22
Orbital Elements and Local-Vertical-Local-Horizontal Frame 10 2.3 Equinoctial Frame with respect to ECI Frame [17] . . . . . . . . . 14 3.1...position and velocity, classical orbital elements , and equinoctial elements . These methods are detailed in the following sections. 2.1.1 Inertial Position...trajectory. However, if the singularities are unavoidable equinoctial orbital elements could be used. 2.1.3 Equinoctial Elements . Equinoctial
Medical catheters thermally manipulated by fiber optic bundles
Chastagner, P.
1992-10-06
A maneuverable medical catheter comprising a flexible tube having a functional tip is described. The catheter is connected to a control source. The functional tip of the catheter carries a plurality of temperature activated elements arranged in parallel and disposed about the functional tip and held in spaced relation at each end. These elements expand when they are heated. A plurality of fiber optic bundles, each bundle having a proximal end attached to the control source and a distal end attached to one of the elements carry light into the elements where the light is absorbed as heat. By varying the optic fiber that is carrying the light and the intensity of the light, the bending of the elements can be controlled and thus the catheter steered. In an alternate embodiment, the catheter carries a medical instrument for gathering a sample of tissue. The instrument may also be deployed and operated by thermal expansion and contraction of its moving parts. 10 figs.
Mechanism for and method of biasing magnetic sensor
Kautz, David R.
2007-12-04
A magnetic sensor package having a biasing mechanism involving a coil-generated, resistor-controlled magnetic field for providing a desired biasing effect. In a preferred illustrated embodiment, the package broadly comprises a substrate; a magnetic sensor element; a biasing mechanism, including a coil and a first resistance element; an amplification mechanism; a filter capacitor element; and an encapsulant. The sensor is positioned within the coil. A current applied to the coil produces a biasing magnetic field. The biasing magnetic field is controlled by selecting a resistance value for the first resistance element which achieves the desired biasing effect. The first resistance element preferably includes a plurality of selectable resistors, the selection of one or more of which sets the resistance value.
Sensing mode atomic force microscope
Hough, Paul V. C.; Wang, Chengpu
2003-01-01
An atomic force microscope utilizes a pulse release system and improved method of operation to minimize contact forces between a probe tip affixed to a flexible cantilever and a specimen being measured. The pulse release system includes a magnetic particle affixed proximate the probe tip and an electromagnetic coil. When energized, the electromagnetic coil generates a magnetic field which applies a driving force on the magnetic particle sufficient to overcome adhesive forces exhibited between the probe tip and specimen. The atomic force microscope includes two independently displaceable piezo elements operable along a Z-axis. A controller drives the first Z-axis piezo element to provide a controlled approach between the probe tip and specimen up to a point of contact between the probe tip and specimen. The controller then drives the first Z-axis piezo element to withdraw the cantilever from the specimen. The controller also activates the pulse release system which drives the probe tip away from the specimen during withdrawal. Following withdrawal, the controller adjusts the height of the second Z-axis piezo element to maintain a substantially constant approach distance between successive samples.
Large Angle Transient Dynamics (LATDYN) user's manual
NASA Technical Reports Server (NTRS)
Abrahamson, A. Louis; Chang, Che-Wei; Powell, Michael G.; Wu, Shih-Chin; Bingel, Bradford D.; Theophilos, Paula M.
1991-01-01
A computer code for modeling the large angle transient dynamics (LATDYN) of structures was developed to investigate techniques for analyzing flexible deformation and control/structure interaction problems associated with large angular motions of spacecraft. This type of analysis is beyond the routine capability of conventional analytical tools without simplifying assumptions. In some instances, the motion may be sufficiently slow and the spacecraft (or component) sufficiently rigid to simplify analyses of dynamics and controls by making pseudo-static and/or rigid body assumptions. The LATDYN introduces a new approach to the problem by combining finite element structural analysis, multi-body dynamics, and control system analysis in a single tool. It includes a type of finite element that can deform and rotate through large angles at the same time, and which can be connected to other finite elements either rigidly or through mechanical joints. The LATDYN also provides symbolic capabilities for modeling control systems which are interfaced directly with the finite element structural model. Thus, the nonlinear equations representing the structural model are integrated along with the equations representing sensors, processing, and controls as a coupled system.
An evaluation of some strategies for vibration control of flexible rotors
NASA Technical Reports Server (NTRS)
Burrows, C. R.
1992-01-01
There is evidence that the reliability of magnetic bearings has achieved an acceptable level in applications when high cost can be tolerated. This acceptability would be enhanced if the inherent capability of magnetic bearings as active control elements were fully used. The technological and commercial promise of magnetic bearings will be fulfilled only if attention is focussed on the control problems associated with their use. The open loop adaptive control algorithm provides an efficient method of controlling the vibration of rotors without the need of a prior knowledge of parameter values. It overcomes the disadvantages normally associated with open loop control while avoiding the problem of instability associated with closed loop control algorithms. The algorithm is conceptually satisfying because it uses the capability of magnetic bearings as fully active vibration control elements rather than limiting them to act as adjustable stiffness and damping elements, as is the case when they are used with local position and velocity feedback.
Nagle, Aniket; Riener, Robert; Wolf, Peter
2015-01-01
Computer games are increasingly being used for training cognitive functions like working memory and attention among the growing population of older adults. While cognitive training games often include elements like difficulty adaptation, rewards, and visual themes to make the games more enjoyable and effective, the effect of different degrees of afforded user control in manipulating these elements has not been systematically studied. To address this issue, two distinct implementations of the three aforementioned game elements were tested among healthy older adults (N = 21, 69.9 ± 6.4 years old) playing a game-like version of the n-back task on a tablet at home for 3 weeks. Two modes were considered, differentiated by the afforded degree of user control of the three elements: user control of difficulty vs. automatic difficulty adaptation, difficulty-dependent rewards vs. automatic feedback messages, and user choice of visual theme vs. no choice. The two modes (“USER-CONTROL” and “AUTO”) were compared for frequency of play, duration of play, and in-game performance. Participants were free to play the game whenever and for however long they wished. Participants in USER-CONTROL exhibited significantly higher frequency of playing, total play duration, and in-game performance than participants in AUTO. The results of the present study demonstrate the efficacy of providing user control in the three game elements, while validating a home-based study design in which participants were not bound by any training regimen, and could play the game whenever they wished. The results have implications for designing cognitive training games that elicit higher compliance and better in-game performance, with an emphasis on home-based training. PMID:26635681
Control of small phased-array antennas
NASA Technical Reports Server (NTRS)
Doland, G. D.
1978-01-01
Series of reports, patent descriptions, calculator programs, and other literature describes antenna control and steering apparatus for seven-element phased array. Though series contains information specific to particular system, it illustrates methods that can be applied to antennas with greater or fewer numbers of elements. Included are programs for calculating beam parameters and design functions and information to interfacing digital controller to beam-steering apparatus.
Finite element approximation of an optimal control problem for the von Karman equations
NASA Technical Reports Server (NTRS)
Hou, L. Steven; Turner, James C.
1994-01-01
This paper is concerned with optimal control problems for the von Karman equations with distributed controls. We first show that optimal solutions exist. We then show that Lagrange multipliers may be used to enforce the constraints and derive an optimality system from which optimal states and controls may be deduced. Finally we define finite element approximations of solutions for the optimality system and derive error estimates for the approximations.
Roman, W.G.
1961-06-27
A pressurized water reactor in which automatic control is achieved by varying the average density of the liquid moderator-cooiant is patented. Density is controlled by the temperature and power level of the reactor ftself. This control can be effected by the use of either plate, pellet, or tubular fuel elements. The fuel elements are disposed between upper and lower coolant plenum chambers and are designed to permit unrestricted coolant flow. The control chamber has an inlet opening communicating with the lower coolant plenum chamber and a restricted vapor vent communicating with the upper coolant plenum chamber. Thus, a variation in temperature of the fuel elements will cause a variation in the average moderator density in the chamber which directly affects the power level of the reactor.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Natzkov, S.; Nikolov, M.
1995-12-01
The design life of the main power equipment-boilers and turbines is about 105 working hours. The possibilities for life extension are after normatively regulated control tests. The diagnostics and methodology for Boilers and Turbines Elements Remaining Life Assessment using up to date computer programs, destructive and nondestructive control of metal of key elements of units equipment, metal creep and low cycle fatigue calculations. As well as data for most common damages and some technical decisions for elements life extension are presented.
Active Vibration Control of a Railway Vehicle Carbody Using Piezoelectric Elements
NASA Astrophysics Data System (ADS)
Molatefi, Habibollah; Ayoubi, Pejman; Mozafari, Hozhabr
2017-07-01
In recent years and according to modern transportation development, rail vehicles are manufactured lighter to achieve higher speed and lower transportation costs. On the other hand, weight reduction of rail vehicles leads to increase the structural vibration. In this study, Active Vibration Control of a rail vehicle using piezoelectric elements is investigated. The optimal control employed as the control approach regard to the first two modes of vibration. A simplified Car body structure is modeled in Matlab using the finite element theory by considering six DOF beam element and then the Eigen functions and mode shapes are derived. The surface roughness of different classes of rail tracks have been obtained using random vibration theory and applied to the secondary suspension as the excitation of the structure; Then piezoelectric mounted where the greatest moments were captured. The effectiveness of Piezoelectric in structural vibrations attenuation of car body is demonstrated through the state space equations and its effect on modal coefficient.
Transparent multi-zone crystal growth furnace and method for controlling the same
NASA Technical Reports Server (NTRS)
Batur, Celal (Inventor); Bennett, Robert J. (Inventor); Duval, Walter (Inventor)
2000-01-01
A crystal growth system, comprising: a furnace; a plurality of heating elements coupled to said furnace, each said plurality of heating elements defining a heat zone, each said heating element set to a desired temperature value; a plurality of thermocouples associated with respective heat zones to detect a temperature value; a translation system for passing an ampoule containing crystal growth material through said furnace into said heat zones and providing a positional location of said ampoule and; a multi-variable self-tuning temperature controller connected to said plurality of heating elements, said plurality of thermocouples and said translation system, said controller monitoring each said zone temperature value and upon considering the thermal interaction of heating zones and the moving thermal inertia of the ampoule, adjusting voltage input to said heat zones to obtain optimal crystal growth within said ampoule.
Transparent multi-zone crystal growth furnace and method for controlling the same
NASA Technical Reports Server (NTRS)
Batur, Celal (Inventor); Duval, Walter (Inventor); Bennett, Robert J. (Inventor)
2001-01-01
A crystal growth system, comprising: a furnace; a plurality of heating elements coupled to said furnace, each said plurality of heating elements defining a heat zone, each said heating element set to a desired temperature value; a plurality of thermocouples associated with respective heat zones to detect a temperature value; a translation system for passing an ampoule containing crystal growth material through said furnace into said heat zones and providing a positional location of said ampoule and; a multi-variable self-tuning temperature controller connected to said plurality of heating elements, said plurality of thermocouples and said translation system, said controller monitoring each said zone temperature value and upon considering the thermal interaction of heating zones and the moving thermal inertia of the ampoule, adjusting voltage input to said heat zones to obtain optimal crystal growth within said ampoule.
Automatic inoculating apparatus. [includes movable carraige, drive motor, and swabbing motor
NASA Technical Reports Server (NTRS)
Wilkins, J. R.; Mills, S. M. (Inventor)
1974-01-01
An automatic inoculating apparatus for agar trays is described and using a simple inoculating element, such as a cotton swab or inoculating loop. The apparatus includes a movable carriage for supporting the tray to be inoculated, a drive motor for moving the tray along a trackway, and a swabbing motor for automatically swabbing the tray during the movement. An actuator motor controls lowering of the inoculating element onto the tray and lifting of the inoculating element. An electrical control system, including limit microswitches, enables automatic control of the actuator motor and return of the carriage to the initial position after inoculating is completed.
Focusing light through random scattering media by four-element division algorithm
NASA Astrophysics Data System (ADS)
Fang, Longjie; Zhang, Xicheng; Zuo, Haoyi; Pang, Lin
2018-01-01
The focusing of light through random scattering materials using wavefront shaping is studied in detail. We propose a newfangled approach namely four-element division algorithm to improve the average convergence rate and signal-to-noise ratio of focusing. Using 4096 independently controlled segments of light, the intensity at the target is 72 times enhanced over the original intensity at the same position. The four-element division algorithm and existing phase control algorithms of focusing through scattering media are compared by both of the numerical simulation and the experiment. It is found that four-element division algorithm is particularly advantageous to improve the average convergence rate of focusing.
Speed control system for an access gate
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bzorgi, Fariborz M
2012-03-20
An access control apparatus for an access gate. The access gate typically has a rotator that is configured to rotate around a rotator axis at a first variable speed in a forward direction. The access control apparatus may include a transmission that typically has an input element that is operatively connected to the rotator. The input element is generally configured to rotate at an input speed that is proportional to the first variable speed. The transmission typically also has an output element that has an output speed that is higher than the input speed. The input element and the outputmore » element may rotate around a common transmission axis. A retardation mechanism may be employed. The retardation mechanism is typically configured to rotate around a retardation mechanism axis. Generally the retardation mechanism is operatively connected to the output element of the transmission and is configured to retard motion of the access gate in the forward direction when the first variable speed is above a control-limit speed. In many embodiments the transmission axis and the retardation mechanism axis are substantially co-axial. Some embodiments include a freewheel/catch mechanism that has an input connection that is operatively connected to the rotator. The input connection may be configured to engage an output connection when the rotator is rotated at the first variable speed in a forward direction and configured for substantially unrestricted rotation when the rotator is rotated in a reverse direction opposite the forward direction. The input element of the transmission is typically operatively connected to the output connection of the freewheel/catch mechanism.« less
Using Large-Scale Roughness Elements to Control Sand and Dust Flux at the Keeler Dunes, Keeler, CA
NASA Astrophysics Data System (ADS)
Gillies, John; McCarley-Holder, Grace
2014-05-01
Controlling dust emission from areas that subsequently degrade air quality and threaten human and animal health and reduce the quality of life for people residing in proximity to such sources is necessary, but also challenging. Recent research has indicated that arrays of large roughness elements (height >0.3 m) can be used effectively to modulate sand transport and the associated dust emissions. Prediction of the rate of sand flux reduction as a function of downwind distance upon entering an array of roughness elements, and the equilibrium flux reduction in the interior of the array is possible using the known geometric properties of the roughness elements, their number, and published relationships. Air quality in the town of Keeler, CA (36 deg 29' 17.92" N, 117 deg 52' 24.62" W) is degraded by levels of particulate matter <10 µm aerodynamic diameter (PM10) during periods of elevated wind speeds due to sand transport and dust emissions in the nearby Keeler Dunes. A demonstration project was designed to evaluate the effectiveness of an array of roughness elements composed of solid elements and managed vegetation to meet sand and dust flux reduction criteria. This project has two major goals: 1) to demonstrate that solid roughness elements placed on areas of the Keeler Dunes immediately arrest sand movement to specified levels (target of 85% reduction), and 2) to assess whether native plant species, planted in the sheltered area of the solid roughness elements can effectively thrive and subsequently replace the solid roughness to achieve the desired sand flux reduction control efficiency. This poster describes the results related mostly to objective one, as considerable time has to pass before sufficient data will be obtained to evaluate the success of the planted and managed vegetation to achieve a control level provided by the solid element roughness array.
Architecture for distributed actuation and sensing using smart piezoelectric elements
NASA Astrophysics Data System (ADS)
Etienne-Cummings, Ralph; Pourboghrat, Farzad; Maruboyina, Hari K.; Abrate, Serge; Dhali, Shirshak K.
1998-07-01
We discuss vibration control of a cantilevered plate with multiple sensors and actuators. An architecture is chosen to minimize the number of control and sensing wires required. A custom VLSI chip, integrated with the sensor/actuator elements, controls the local behavior of the plate. All the actuators are addressed in parallel; local decode logic selects which actuator is stimulated. Downloaded binary data controls the applied voltage and modulation frequency for each actuator, and High Voltage MOSFETs are used to activate them. The sensors, which are independent adjacent piezoelectric ceramic elements, can be accessed in a random or sequential manner. An A/D card and GPIB interconnected test equipment allow a PC to read the sensors' outputs and dictate the actuation procedure. A visual programming environment is used to integrate the sensors, controller and actuators. Based on the constitutive relations for the piezoelectric material, simple models for the sensors and actuators are derived. A two level hierarchical robust controller is derived for motion control and for damping of vibrations.
Cho, Ah-Reum; Cho, Sang-Bong; Lee, Jae-Ho; Kim, Kyung-Hoon
2015-11-01
Vertebroplasty is an effective treatment for osteoporotic vertebral fractures, which are one of the most common fractures associated with osteoporosis. However, clinical observation has shown that the risk of adjacent vertebral body fractures may increase after vertebroplasty. The mechanism underlying adjacent vertebral body fracture after vertebroplasty is not clear; excessive stiffness resulting from polymethyl methacrylate has been suspected as an important mechanism. The aim of our study was to compare the effects of bone cement stiffness on adjacent vertebrae after osteoporotic vertebroplasty under load-controlled versus displacement-controlled conditions. An experimental computer study using a finite element analysis. Medical research institute, university hospital, Korean. A three-dimensional digital anatomic model of L1/2 bone structure was reconstructed from human computed tomographic images. The reconstructed three-dimensional geometry was processed for finite element analysis such as meshing elements and applying material properties. Two boundary conditions, load-controlled and displacement-controlled methods, were applied to each of 5 deformation modes: compression, flexion, extension, lateral bending, and torsion. The adjacent L1 vertebra, irrespective of augmentation, revealed nearly similar maximum von Mises stresses under the load-controlled condition. However, for the displacement-controlled condition, the maximum von Mises stresses in the cortical bone and inferior endplate of the adjacent L1 vertebra increased significantly after cement augmentation. This increase was more significant than that with stiffer bone cement under all modes, except the torsion mode. The finite element model was simplified, excluding muscular forces and incorporating a large volume of bone cement, to more clearly demonstrate effects of bone cement stiffness on adjacent vertebrae after vertebroplasty. Excessive stiffness of augmented bone cement increases the risk of adjacent vertebral fractures after vertebroplasty in an osteoporotic finite element model. This result was most prominently observed using the displacement-controlled method.
Assessment of serum trace elements and electrolytes in children with childhood and atypical autism.
Skalny, Anatoly V; Simashkova, Natalia V; Klyushnik, Tatiana P; Grabeklis, Andrei R; Radysh, Ivan V; Skalnaya, Margarita G; Nikonorov, Alexandr A; Tinkov, Alexey A
2017-09-01
The existing data demonstrate a significant interrelation between ASD and essential and toxic trace elements status of the organism. However, data on trace element homeostasis in particular ASD forms are insufficient. Therefore, the objective of the present study was to assess the level of trace elements and electrolytes in serum of children with childhood and atypical autism. A total of 48 children with ASD (24 with childhood and 24 with atypical autism) and age- and sex-adjusted controls were examined. Serum trace elements and electrolytes were assessed using inductively-coupled plasma mass spectrometry. The obtained data demonstrate that children with ASD unspecified are characterized by significantly lower Ni, Cr, and Se levels as compared to the age- and sex-matched controls. At the same time, significantly decreased serum Ni and Se concentrations were detected in patients with childhood autism. In turn, children with atypical autism were characterized by more variable serum trace element spectrum. In particular, atypical autism is associated with lower serum Al, As, Ni, Cr, Mn, and Se levels in comparison to the control values. Moreover, Al and Mn concentration in this group was also lower than that in childhood autism patients. Generally, the obtained data demonstrate lower levels of both essential and toxic trace elements in atypical autism group, being indicative of profound alteration of trace elements metabolism. However, further detailed metabolic studies are required to reveal critical differences in metabolic pathways being responsible for difference in trace element status and clinical course of the disease. Copyright © 2016 Elsevier GmbH. All rights reserved.
NASA Technical Reports Server (NTRS)
Parra, G. T. (Inventor)
1978-01-01
An angle detector for determining a transducer's angular disposition to a capacitive pickup element is described. The transducer comprises a pendulum mounted inductive element moving past the capacitive pickup element. The capacitive pickup element divides the inductive element into two parts L sub 1 and L sub 2 which form the arms of one side of an a-c bridge. Two networks R sub 1 and R sub 2 having a plurality of binary weighted resistors and an equal number of digitally controlled switches for removing resistors from the networks form the arms of the other side of the a-c bridge. A binary counter, controlled by a phase detector, balances the bridge by adjusting the resistance of R sub 1 and R sub 2. The binary output of the counter is representative of the angle.
Dynamic control of spin states in interacting magnetic elements
Jain, Shikha; Novosad, Valentyn
2014-10-07
A method for the control of the magnetic states of interacting magnetic elements comprising providing a magnetic structure with a plurality of interacting magnetic elements. The magnetic structure comprises a plurality of magnetic states based on the state of each interacting magnetic element. The desired magnetic state of the magnetic structure is determined. The active resonance frequency and amplitude curve of the desired magnetic state is determined. Each magnetic element of the magnetic structure is then subjected to an alternating magnetic field or electrical current having a frequency and amplitude below the active resonance frequency and amplitude curve of said desired magnetic state and above the active resonance frequency and amplitude curve of the current state of the magnetic structure until the magnetic state of the magnetic structure is at the desired magnetic state.
Selection of combined water electrolysis and resistojet propulsion for Space Station Freedom
NASA Technical Reports Server (NTRS)
Schmidt, George R.
1988-01-01
An analytical rationale is presented for the configuration of the NASA Space Station's two-element propulsion system, and attention is given to the cost benefits accruing to this system over the Space Station's service life. The principal system element uses gaseous oxygen and hydrogen obtained through water electrolysis to furnish attitude control, backup attitude control, and contingency maneuvering. The secondary element uses resistojets to augment Space Station reboost through the acceleration of waste gases in the direction opposite the Station's flight path.
Transcriptional switches in the control of macronutrient metabolism.
Wise, Alan
2008-06-01
This review shows how some transcription factors respond to alterations in macronutrients. Carbohydrates induce enzymes for their metabolism and fatty acid synthesis. Fatty acids reduce carbohydrate processing, induce enzymes for their metabolism, and increase both gluconeogenesis and storage of fat. Fat stores help control carbohydrate uptake by other cells. The following main transcription factors are discussed: carbohydrate response element-binding protein; sterol regulatory element-binding protein-1c, cyclic AMP response element-binding protein, peroxisome proliferator-activated receptor-alpha, and peroxisome proliferator-activated receptor-gamma.
2016-10-01
testing as well as finite element simulation. Automation and control testing has been completed on a 5x5 array of bubble actuators to verify pressure...mechanical behavior at varying loads and internal pressures both by experimental testing as well as finite element simulation. Automation and control...A finite element (FE) model of the bubble actuator was developed in the commercial software ANSYS in order to determine the deformation of the
Code of Federal Regulations, 2013 CFR
2013-07-01
... Defense Department of Defense (Continued) DEPARTMENT OF THE AIR FORCE CLAIMS AND LITIGATION ADMINISTRATIVE... military purpose and used or controlled by the Air Force or any other Department of Defense (DOD) element... area or any real estate the Air Force or any other DOD element uses or controls. (d) Personal property...
New reaction conditions and stereochemical control elements for heterodimerization between ethylene (or propylene) and functionalized vinyl arenes are highlighted (see equation). For example, an enantioselective version of the hydrovinylation reaction uses [{(allyl)NiBr}...
ERIC Educational Resources Information Center
Nelson, David A.; Yang, Chongming; Coyne, Sarah M.; Olsen, Joseph A.; Hart, Craig H.
2013-01-01
Parental psychological control generally consists of overinvolved/protective and critical/rejecting elements, both being linked to children's psychosocial maladjustment. The critical/rejecting element is multidimensional in nature, and few studies have explored this conceptual fullness. It is possible that some dimensions, if they can be…
Control of large flexible structures - An experiment on the NASA Mini-Mast facility
NASA Technical Reports Server (NTRS)
Hsieh, Chen; Kim, Jae H.; Liu, Ketao; Zhu, Guoming; Skelton, Robert E.
1991-01-01
The output variance constraint controller design procedure is integrated with model reduction by modal cost analysis. A procedure is given for tuning MIMO controller designs to find the maximal rms performance of the actual system. Controller designs based on a finite-element model of the system are compared with controller designs based on an identified model (obtained using the Q-Markov Cover algorithm). The identified model and the finite-element model led to similar closed-loop performance, when tested in the Mini-Mast facility at NASA Langley.
Automatized alignment control of wing mechanization in aerodynamic contour of aircraft
NASA Astrophysics Data System (ADS)
Odnokurtsev, K. A.
2018-05-01
The method of automatized control of accuracy of an aircraft aerodynamic contour when mounting wing mechanization elements is described in the article. A control device in the stand of the wing assembling, equipped with the distance sensors, is suggested to be used. The measurement of control points’ inaccuracies is made automatically in a special computer program. Two kinds of sensor calibration are made in advance in order to increase the accuracy of measurements. As a result, the duration of control and adjustment of mechanization elements is reduced.
Development of a Design Methodology for Reconfigurable Flight Control Systems
NASA Technical Reports Server (NTRS)
Hess, Ronald A.; McLean, C.
2000-01-01
A methodology is presented for the design of flight control systems that exhibit stability and performance-robustness in the presence of actuator failures. The design is based upon two elements. The first element consists of a control law that will ensure at least stability in the presence of a class of actuator failures. This law is created by inner-loop, reduced-order, linear dynamic inversion, and outer-loop compensation based upon Quantitative Feedback Theory. The second element consists of adaptive compensators obtained from simple and approximate time-domain identification of the dynamics of the 'effective vehicle' with failed actuator(s). An example involving the lateral-directional control of a fighter aircraft is employed both to introduce the proposed methodology and to demonstrate its effectiveness and limitations.
Cis-regulatory RNA elements that regulate specialized ribosome activity.
Xue, Shifeng; Barna, Maria
2015-01-01
Recent evidence has shown that the ribosome itself can play a highly regulatory role in the specialized translation of specific subpools of mRNAs, in particular at the level of ribosomal proteins (RP). However, the mechanism(s) by which this selection takes place has remained poorly understood. In our recent study, we discovered a combination of unique RNA elements in the 5'UTRs of mRNAs that allows for such control by the ribosome. These mRNAs contain a Translation Inhibitory Element (TIE) that inhibits general cap-dependent translation, and an Internal Ribosome Entry Site (IRES) that relies on a specific RP for activation. The unique combination of an inhibitor of general translation and an activator of specialized translation is key to ribosome-mediated control of gene expression. Here we discuss how these RNA regulatory elements provide a new level of control to protein expression and their implications for gene expression, organismal development and evolution.
A weak Hamiltonian finite element method for optimal control problems
NASA Technical Reports Server (NTRS)
Hodges, Dewey H.; Bless, Robert R.
1989-01-01
A temporal finite element method based on a mixed form of the Hamiltonian weak principle is developed for dynamics and optimal control problems. The mixed form of Hamilton's weak principle contains both displacements and momenta as primary variables that are expanded in terms of nodal values and simple polynomial shape functions. Unlike other forms of Hamilton's principle, however, time derivatives of the momenta and displacements do not appear therein; instead, only the virtual momenta and virtual displacements are differentiated with respect to time. Based on the duality that is observed to exist between the mixed form of Hamilton's weak principle and variational principles governing classical optimal control problems, a temporal finite element formulation of the latter can be developed in a rather straightforward manner. Several well-known problems in dynamics and optimal control are illustrated. The example dynamics problem involves a time-marching problem. As optimal control examples, elementary trajectory optimization problems are treated.
A weak Hamiltonian finite element method for optimal control problems
NASA Technical Reports Server (NTRS)
Hodges, Dewey H.; Bless, Robert R.
1990-01-01
A temporal finite element method based on a mixed form of the Hamiltonian weak principle is developed for dynamics and optimal control problems. The mixed form of Hamilton's weak principle contains both displacements and momenta as primary variables that are expanded in terms of nodal values and simple polynomial shape functions. Unlike other forms of Hamilton's principle, however, time derivatives of the momenta and displacements do not appear therein; instead, only the virtual momenta and virtual displacements are differentiated with respect to time. Based on the duality that is observed to exist between the mixed form of Hamilton's weak principle and variational principles governing classical optimal control problems, a temporal finite element formulation of the latter can be developed in a rather straightforward manner. Several well-known problems in dynamics and optimal control are illustrated. The example dynamics problem involves a time-marching problem. As optimal control examples, elementary trajectory optimization problems are treated.
Weak Hamiltonian finite element method for optimal control problems
NASA Technical Reports Server (NTRS)
Hodges, Dewey H.; Bless, Robert R.
1991-01-01
A temporal finite element method based on a mixed form of the Hamiltonian weak principle is developed for dynamics and optimal control problems. The mixed form of Hamilton's weak principle contains both displacements and momenta as primary variables that are expanded in terms of nodal values and simple polynomial shape functions. Unlike other forms of Hamilton's principle, however, time derivatives of the momenta and displacements do not appear therein; instead, only the virtual momenta and virtual displacements are differentiated with respect to time. Based on the duality that is observed to exist between the mixed form of Hamilton's weak principle and variational principles governing classical optimal control problems, a temporal finite element formulation of the latter can be developed in a rather straightforward manner. Several well-known problems in dynamics and optimal control are illustrated. The example dynamics problem involves a time-marching problem. As optimal control examples, elementary trajectory optimization problems are treated.
Finite element solution of optimal control problems with state-control inequality constraints
NASA Technical Reports Server (NTRS)
Bless, Robert R.; Hodges, Dewey H.
1992-01-01
It is demonstrated that the weak Hamiltonian finite-element formulation is amenable to the solution of optimal control problems with inequality constraints which are functions of both state and control variables. Difficult problems can be treated on account of the ease with which algebraic equations can be generated before having to specify the problem. These equations yield very accurate solutions. Owing to the sparse structure of the resulting Jacobian, computer solutions can be obtained quickly when the sparsity is exploited.
Reduced modeling of flexible structures for decentralized control
NASA Technical Reports Server (NTRS)
Yousuff, A.; Tan, T. M.; Bahar, L. Y.; Konstantinidis, M. F.
1986-01-01
Based upon the modified finite element-transfer matrix method, this paper presents a technique for reduced modeling of flexible structures for decentralized control. The modeling decisions are carried out at (finite-) element level, and are dictated by control objectives. A simply supported beam with two sets of actuators and sensors (linear force actuator and linear position and velocity sensors) is considered for illustration. In this case, it is conjectured that the decentrally controlled closed loop system is guaranteed to be at least marginally stable.
Wavefront sensing and control aspects in a high energy laser optical train
NASA Astrophysics Data System (ADS)
Bartosewcz, M.; Bareket, N.
1981-01-01
In this paper we review the major elements of a HEL (high energy laser) wavefront sensing and control system with particular emphasis on experimental demonstrations and hardware components developed at Lockheed Missiles & Space Company, Inc. The review concentrates on three important elements of wavefront control: wavefront sampling, wavefront sensing and active mirrors. Methods of wavefront sampling by diffraction gratings are described. Some new developments in wavefront sensing are explored. Hardware development efforts of fast steering mirrors and edge controlled deformable mirrors are described.
49 CFR 236.744 - Element, roadway.
Code of Federal Regulations, 2013 CFR
2013-10-01
... 49 Transportation 4 2013-10-01 2013-10-01 false Element, roadway. 236.744 Section 236.744 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION... Element, roadway. That portion of the roadway apparatus of automatic train stop, train control, or cab...
49 CFR 236.744 - Element, roadway.
Code of Federal Regulations, 2011 CFR
2011-10-01
... 49 Transportation 4 2011-10-01 2011-10-01 false Element, roadway. 236.744 Section 236.744 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION... Element, roadway. That portion of the roadway apparatus of automatic train stop, train control, or cab...
49 CFR 236.744 - Element, roadway.
Code of Federal Regulations, 2014 CFR
2014-10-01
... 49 Transportation 4 2014-10-01 2014-10-01 false Element, roadway. 236.744 Section 236.744 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION... Element, roadway. That portion of the roadway apparatus of automatic train stop, train control, or cab...
49 CFR 236.744 - Element, roadway.
Code of Federal Regulations, 2012 CFR
2012-10-01
... 49 Transportation 4 2012-10-01 2012-10-01 false Element, roadway. 236.744 Section 236.744 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION... Element, roadway. That portion of the roadway apparatus of automatic train stop, train control, or cab...
NASA Technical Reports Server (NTRS)
Rajagopalan, Harish; Rahmat-Samii, Yahya; Imbriale, William A.
2007-01-01
The purpose of this paper is to investigate potential reflectarray elements by taking into consideration the eventual implementation of MEMS technology for this particular application and detailed characterization of one of the potential element designs.
Improving Organisational Effectiveness of Coalition Operations
2010-04-01
does not display a currently valid OMB control number. 1. REPORT DATE APR 2010 2. REPORT TYPE N/A 3. DATES COVERED - 4. TITLE AND SUBTITLE...only marginally concrete elements of an organisation that can hardly be described. These elements develop permanently and can be planed or controlled ...structure is the formal system of task and authority relationships that control how people coordinate their actions and use resources to achieve
Simulation of a Canard in Fluid Flow Driven by a Piezoelectric Beam with a Software Control Loop
2014-04-01
The canard is actuated by a piezoelectric beam that bends as voltage is applied. The voltage is controlled by a software subroutine that measures...Dynamic system Modeling Co-simulation Simulation Abaqus Finite element analysis (FEA) Finite element method (FEM) Computational...is unlimited. i CONTENTS Page Introduction 1 Model Description 1 Fluid Model 2 Structural Model 3 Control Subroutine 4 Results 4
NASA Astrophysics Data System (ADS)
Ostachowicz, B.; Lankosz, M.; Tomik, B.; Adamek, D.; Wobrauschek, P.; Streli, C.; Kregsamer, P.
2006-11-01
Trace elements play an important role in the human central nervous system. Significant variations of the concentration of trace elements in body fluids may occur in neurodegenerative diseases. In the present work an investigation of the elemental composition of the serum, and the cerebrospinal fluid in amyotrophic lateral sclerosis patients and a control group was performed. For the analysis of the body fluids Total reflection X-ray Fluorescence (TXRF) spectrometry was used. The samples were taken during routine diagnostic procedures. Na, Mg, Cl, K, Ca, Cu, Zn, and Br were determined in both fluids. In order to validate the results of analysis a serum standard reference material was measured. A t-test was applied to check if the mean concentrations of the elements are different for ALS and the control group. For the serum samples higher values for Br were found in the ALS group, for the cerebrospinal fluid lower values of Na, Mg and Zn as well as higher Ca values were found in the ALS group compared to the control group.
Structural Elements Regulating AAA+ Protein Quality Control Machines.
Chang, Chiung-Wen; Lee, Sukyeong; Tsai, Francis T F
2017-01-01
Members of the ATPases Associated with various cellular Activities (AAA+) superfamily participate in essential and diverse cellular pathways in all kingdoms of life by harnessing the energy of ATP binding and hydrolysis to drive their biological functions. Although most AAA+ proteins share a ring-shaped architecture, AAA+ proteins have evolved distinct structural elements that are fine-tuned to their specific functions. A central question in the field is how ATP binding and hydrolysis are coupled to substrate translocation through the central channel of ring-forming AAA+ proteins. In this mini-review, we will discuss structural elements present in AAA+ proteins involved in protein quality control, drawing similarities to their known role in substrate interaction by AAA+ proteins involved in DNA translocation. Elements to be discussed include the pore loop-1, the Inter-Subunit Signaling (ISS) motif, and the Pre-Sensor I insert (PS-I) motif. Lastly, we will summarize our current understanding on the inter-relationship of those structural elements and propose a model how ATP binding and hydrolysis might be coupled to polypeptide translocation in protein quality control machines.
Elastic actuator for precise force control
Pratt, G.A.; Williamson, M.M.
1997-07-22
The invention provides an elastic actuator consisting of a motor and a motor drive transmission connected at an output of the motor. An elastic element is connected in series with the motor drive transmission, and this elastic element is positioned to alone support the full weight of any load connected at an output of the actuator. A single force transducer is positioned at a point between a mount for the motor and an output of the actuator. This force transducer generates a force signal, based on deflection of the elastic element, that indicates force applied by the elastic element to an output of the actuator. An active feedback force control loop is connected between the force transducer and the motor for controlling the motor. This motor control is based on the force signal to deflect the elastic element an amount that produces a desired actuator output force. The produced output force is substantially independent of load motion. The invention also provides a torsional spring consisting of a flexible structure having at least three flat sections each connected integrally with and extending radially from a central section. Each flat section extends axially along the central section from a distal end of the central section to a proximal end of the central section. 30 figs.
Elastic actuator for precise force control
Pratt, Gill A.; Williamson, Matthew M.
1997-07-22
The invention provides an elastic actuator consisting of a motor and a motor drive transmission connected at an output of the motor. An elastic element is connected in series with the motor drive transmission, and this elastic element is positioned to alone support the full weight of any load connected at an output of the actuator. A single force transducer is positioned at a point between a mount for the motor and an output of the actuator. This force transducer generates a force signal, based on deflection of the elastic element, that indicates force applied by the elastic element to an output of the actuator. An active feedback force control loop is connected between the force transducer and the motor for controlling the motor. This motor control is based on the force signal to deflect the elastic element an amount that produces a desired actuator output force. The produced output force is substantially independent of load motion. The invention also provides a torsional spring consisting of a flexible structure having at least three flat sections each connected integrally with and extending radially from a central section. Each flat section extends axially along the central section from a distal end of the central section to a proximal end of the central section.
Trace elements and heavy metals in hair of stage III breast cancer patients.
Benderli Cihan, Yasemin; Sözen, Selim; Oztürk Yıldırım, Sema
2011-12-01
This prospective study was designed to compare the hair levels of 36 elements in 52 patients with stage III breast cancer to those of an equal number of healthy individuals. Principal component and cluster analysis were used for source of identification and apportionment of heavy metals and trace elements in these two groups. A higher average level of iron was found in samples from patients while controls had higher levels of calcium. Both patients and controls had elevated levels of tin, magnesium, zinc, and sodium. Almost all element values in cancer patients showed higher dispersion and asymmetry than in healthy controls. Between the two groups, there were statistically significant differences in the concentrations of silver, arsenic, gold, boron, barium, beryllium, calcium, cadmium, cerium, cobalt, cesium, gadolinium, manganese, nickel, lead, antimony, scandium, selenium, and zinc (p < 0.05). Strong positive correlations were found between lead and gold (r = 0.785) in the cancer group and between palladium and cobalt (r = 0.945) in the healthy individuals. Our results show that there are distinct patterns of heavy metals and trace elements in the hair of breast cancer patients in comparison to healthy controls. These results could be of significance in the diagnosis of breast cancer.
Quantitative analysis of biomedical samples using synchrotron radiation microbeams
NASA Astrophysics Data System (ADS)
Ektessabi, Ali; Shikine, Shunsuke; Yoshida, Sohei
2001-07-01
X-ray fluorescence (XRF) using a synchrotron radiation (SR) microbeam was applied to investigate distributions and concentrations of elements in single neurons of patients with neurodegenerative diseases. In this paper we introduce a computer code that has been developed to quantify the trace elements and matrix elements at the single cell level. This computer code has been used in studies of several important neurodegenerative diseases such as Alzheimer's disease (AD), Parkinson's disease (PD) and parkinsonism-dementia complex (PDC), as well as in basic biological experiments to determine the elemental changes in cells due to incorporation of foreign metal elements. The substantial nigra (SN) tissue obtained from the autopsy specimens of patients with Guamanian parkinsonism-dementia complex (PDC) and control cases were examined. Quantitative XRF analysis showed that neuromelanin granules of Parkinsonian SN contained higher levels of Fe than those of the control. The concentrations were in the ranges of 2300-3100 ppm and 2000-2400 ppm respectively. On the contrary, Zn and Ni in neuromelanin granules of SN tissue from the PDC case were lower than those of the control. Especially Zn was less than 40 ppm in SN tissue from the PDC case while it was 560-810 ppm in the control. These changes are considered to be closely related to the neuro-degeneration and cell death.
Automatic control of a primary electric thrust subsystem
NASA Technical Reports Server (NTRS)
Macie, T. W.; Macmedan, M. L.
1975-01-01
A concept for automatic control of the thrust subsystem has been developed by JPL and participating NASA Centers. This paper reports on progress in implementing the concept at JPL. Control of the Thrust Subsystem (TSS) is performed by the spacecraft computer command subsystem, and telemetry data is extracted by the spacecraft flight data subsystem. The Data and Control Interface Unit, an element of the TSS, provides the interface with the individual elements of the TSS. The control philosophy and implementation guidelines are presented. Control requirements are listed, and the control mechanism, including the serial digital data intercommunication system, is outlined. The paper summarizes progress to Fall 1974.
Energy Efficient Engine: Control system preliminary definition report
NASA Technical Reports Server (NTRS)
Howe, David C.
1986-01-01
The object of the Control Preliminary Definition Program was to define a preliminary control system concept as a part of the Energy Efficient Engine program. The program was limited to a conceptual definition of a full authority digital electronic control system. System requirements were determined and a control system was conceptually defined to these requirements. Areas requiring technological development were identified and a plan was established for implementing the identified technological features, including a control technology demonstration. A significant element of this program was a study of the potential benefits of closed-loop active clearance control, along with laboratory tests of candidate clearance sensor elements for a closed loop system.
Robust controller designs for second-order dynamic system: A virtual passive approach
NASA Technical Reports Server (NTRS)
Juang, Jer-Nan; Phan, Minh
1990-01-01
A robust controller design is presented for second-order dynamic systems. The controller is model-independent and itself is a virtual second-order dynamic system. Conditions on actuator and sensor placements are identified for controller designs that guarantee overall closed-loop stability. The dynamic controller can be viewed as a virtual passive damping system that serves to stabilize the actual dynamic system. The control gains are interpreted as virtual mass, spring, and dashpot elements that play the same roles as actual physical elements in stability analysis. Position, velocity, and acceleration feedback are considered. Simple examples are provided to illustrate the physical meaning of this controller design.
Liu, Xifang; Niu, Xin; Feng, Qianjin; Liu, Yaming
2014-04-01
To explore the effects of five-element music therapy on elderly patients with seasonal affective disorder in a Chinese nursing home. The patients (n = 50) were recruited from a Shijingshan district nursing home in Beijing, China. They were randomly assigned to two groups, a treatment group and a control group, with 25 participants in each group. The patients received music therapy for 1-2 h each week over an 8-week period. The music therapy involved four phases: introduction, activities, listening to the Chinese five-element music, and a concluding phase. The participants in the control group did not listen to the five-element music. This study consisted of two parts: (a) a qualitative study that used focus groups to understand the feelings of the patients with seasonal affective disorder; (b) a quantitative study that involved administration of the self-rating depression scale (SDS) and Hamilton depression scale (HAMD) before and after treatment. (a) Qualitative analysis results: strength derived from the five-element group music therapy and emotional adjustment. The five-element group music therapy can reduce patients' psychological distress and let them feel inner peace and enhance their life satisfaction. (b) No significant difference in SDS and HAMD scores was found between the two groups (P > 0.05) prior to treatment. After treatment, the mean SDS score of the control group was 49.9 +/- 18.8, while the treatment group's score was 40.2 +/- 18.1. The HAMD score of the control group was 11.2 +/-3.1, and the treatment group's score was 8.8 +/- 4.9. Following 8 weeks of music therapy, the SDS and HAMD scores of the treatment group were significantly lower than those for the control group (P < 0.05). Five-element music therapy alleviated the symptoms of seasonal affective disorder in the elderly patients.
NASA Astrophysics Data System (ADS)
Sotner, R.; Kartci, A.; Jerabek, J.; Herencsar, N.; Dostal, T.; Vrba, K.
2012-12-01
Several behavioral models of current active elements for experimental purposes are introduced in this paper. These models are based on commercially available devices. They are suitable for experimental tests of current- and mixed-mode filters, oscillators, and other circuits (employing current-mode active elements) frequently used in analog signal processing without necessity of onchip fabrication of proper active element. Several methods of electronic control of intrinsic resistance in the proposed behavioral models are discussed. All predictions and theoretical assumptions are supported by simulations and experiments. This contribution helps to find a cheaper and more effective way to preliminary laboratory tests without expensive on-chip fabrication of special active elements.
Telescope with a wide field of view internal optical scanner
NASA Technical Reports Server (NTRS)
Zheng, Yunhui (Inventor); Degnan, III, John James (Inventor)
2012-01-01
A telescope with internal scanner utilizing either a single optical wedge scanner or a dual optical wedge scanner and a controller arranged to control a synchronous rotation of the first and/or second optical wedges, the wedges constructed and arranged to scan light redirected by topological surfaces and/or volumetric scatterers. The telescope with internal scanner further incorporates a first converging optical element that receives the redirected light and transmits the redirected light to the scanner, and a second converging optical element within the light path between the first optical element and the scanner arranged to reduce an area of impact on the scanner of the beam collected by the first optical element.
The role of the law in reducing tuberculosis transmission in Botswana, South Africa and Zambia
Emerson, Courtney N; Lederer, Philip; Lipke, Ginny; Kapata, Nathan; Lanje, Samson; Peters, Annatjie C; Zulu, Isaac; Marston, Barbara J; Miller, Bess
2016-01-01
Abstract Objective To determine whether laws and regulations in Botswana, South Africa and Zambia – three countries with a high tuberculosis and HIV infection burden – address elements of the World Health Organization (WHO) policy on tuberculosis infection control. Methods An online desk review of laws and regulations that address six selected elements of the WHO policy on tuberculosis infection control in the three countries was conducted in November 2015 using publicly available domestic legal databases. The six elements covered: (i) national policy and legal framework; (ii) health facility design, construction and use; (iii) tuberculosis disease surveillance among health workers; (iv) patients’ and health workers’ rights; (v) monitoring of infection control measures; and (vi) relevant research. Findings The six elements were found to be adequately addressed in the three countries’ laws and regulations. In all three, tuberculosis case-reporting is required, as is tuberculosis surveillance among health workers. Each country’s legal and regulatory framework also addresses the need to respect individuals’ rights and privacy while safeguarding public health. These laws and regulations create a strong foundation for tuberculosis infection control. Although the legal and regulatory frameworks thoroughly address tuberculosis infection control, their dissemination, implementation and enforcement were not assessed, nor was their impact on public health. Conclusion Laws and regulations in Botswana, South Africa and Zambia address all six selected elements of the WHO policy on tuberculosis infection control. However, the lack of data on their implementation is a limitation. Future research should assess the implementation and public health impact of laws and regulations. PMID:27274593
Finite element method for optimal guidance of an advanced launch vehicle
NASA Technical Reports Server (NTRS)
Hodges, Dewey H.; Bless, Robert R.; Calise, Anthony J.; Leung, Martin
1992-01-01
A temporal finite element based on a mixed form of Hamilton's weak principle is summarized for optimal control problems. The resulting weak Hamiltonian finite element method is extended to allow for discontinuities in the states and/or discontinuities in the system equations. An extension of the formulation to allow for control inequality constraints is also presented. The formulation does not require element quadrature, and it produces a sparse system of nonlinear algebraic equations. To evaluate its feasibility for real-time guidance applications, this approach is applied to the trajectory optimization of a four-state, two-stage model with inequality constraints for an advanced launch vehicle. Numerical results for this model are presented and compared to results from a multiple-shooting code. The results show the accuracy and computational efficiency of the finite element method.
NASA Technical Reports Server (NTRS)
Juday, Richard D. (Inventor)
1998-01-01
An apparatus is disclosed for reading and/or writing information or to from an optical recording medium having a plurality of information storage layers. The apparatus includes a dynamic holographic optical element configured to focus light on the optical recording medium. a control circuit arranged to supply a drive signal to the holographic optical element, and a storage device in communication with the control circuit and storing at least a first drive signal and a second drive signal. The holographic optical element focusses light on a first one of the plurality of information storage layers when driven by the first drive signal on a second one of the plurality of information storage layers when driven by the second drive signal. An optical switch is also disclosed for connecting at least one light source in a source array to at least one light receiver in a receiver array. The switch includes a dynamic holographic optical element configured to receive light from the source array and to transmit light to the receiver array, a control circuit arranged to supply a drive signal to the holographic optical element, and a storage device in communication with the control circuit and storing at least a first drive signal and a second drive signal. The holographic optical element connects a first light source in the source array to a first light receiver in the receiver array when driven by the first drive signal and the holographic optical element connects the first light source with the first light receiver and a second light receiver when driven by the second drive signal.
49 CFR 236.560 - Contact element, mechanical trip type; location with respect to rail.
Code of Federal Regulations, 2011 CFR
2011-10-01
... INSTRUCTIONS GOVERNING THE INSTALLATION, INSPECTION, MAINTENANCE, AND REPAIR OF SIGNAL AND TRAIN CONTROL SYSTEMS, DEVICES, AND APPLIANCES Automatic Train Stop, Train Control and Cab Signal Systems Rules and.... Contact element of automatic train stop device of the mechanical trip type shall be maintained at a height...
Hawke, B.C.
1963-02-26
This patent relates to a releasable coupling connecting a control rod to a control rod drive. This remotely operable coupling mechanism can connect two elements which are laterally and angviarly misaligned, and provides a means for sensing the locked condition of the elements. The coupling utilizes a spherical bayonet joint which is locked against rotation by a ball detent lock. (AEC)
Multinode data acquisition and control system for the 4-element TACTIC telescope array
NASA Astrophysics Data System (ADS)
Yadav, K. K.; Chouhan, N.; Kaul, S. R.; Koul, R.
2002-03-01
An interrupt driven multinode data acquisition and control system has been developed for the 4-element gamma-ray telescope array, TACTIC. Computer networking technology and the CAMAC bus have been integrated to develop this icon-based, userfriendly failsafe system. The paper describes the salient features of the system.
Trace elements in children suffering from sickle cell anemia: A case-control study.
Sungu, Joseph K; Mukuku, Olivier; Mutombo, Augustin Mulangu; Mawaw, Paul; Aloni, Michel N; Luboya, Oscar N
2018-01-01
Information on serum albumin and trace elements among children suffering from Sickle Cell Anemia (SCA) was poorly documented in Africa. The aim of this study was to describe and to compare different values of trace elements with published reports from other parts of the world. We carried out a case-control study. Seventy-six steady state children suffering from SCA (Hb-SS). One hundred and fifty-two children were recruited with 76 (cases, Hb-SS) and 76 (control, Hb-AA) to compare the data. The mean age was 10.0 years (SD=5.4) in SCA children and 9.2 years (SD=4.7) in the control group. The mean level of zinc and magnesium were slightly lower in the Hb-SS group than in the Hb-AA group (P<.001). The first literature about trace elements in SCA is briefly reported in Central Africa. In our midst, zinc, magnesium, and selenium deficiencies underline the need for their systematic among all children with SCA to identify patients with these deficiencies and provide early management. © 2017 Wiley Periodicals, Inc.
Potentially-toxic and essential elements profile of AH1N1 patients in Mexico City
Moya, Mireya; Bautista, Edgar G.; Velázquez-González, Antonio; Vázquez-Gutiérrez, Felipe; Tzintzun, Guadalupe; García-Arreola, María Elena; Castillejos, Manuel; Hernández, Andrés
2013-01-01
During spring of 2009, a new influenza virus AH1N1 spread in the world causing acute respiratory illness and death, resulting in the first influenza pandemic since 1968. Blood levels of potentially-toxic and essential elements of 40 pneumonia and confirmed AH1N1 were evaluated against two different groups of controls, both not infected with the pandemic strain. Significant concentrations of potentially-toxic elements (lead, mercury, cadmium, chromium, arsenic) along with deficiency of selenium or increased Zn/Cu ratios characterized AH1N1 cases under study when evaluated versus controlled cases. Deficiency of selenium is progressively observed from controls I (influenza like illness) through controls II (pneumonia) and finally pneumonia -AH1N1 infected patients. Cases with blood Se levels greater than the recommended for an optimal cut-off to activate glutathione peroxidase (12.5 μg/dL) recovered from illness and survived. Evaluation of this essential element in critical pneumonia patients at the National Institutes is under evaluation as a clinical trial. PMID:23422930
Leroux, Shawn J; Schmitz, Oswald J
2015-11-01
Empirical evidence is beginning to show that predators can be important drivers of elemental cycling within ecosystems by propagating indirect effects that determine the distribution of elements among trophic levels as well as determine the chemical content of organic matter that becomes decomposed by microbes. These indirect effects can be propagated by predator consumptive effects on prey, nonconsumptive (risk) effects, or a combination of both. Currently, there is insufficient theory to predict how such predator effects should propagate throughout ecosystems. We present here a theoretical framework for exploring predator effects on ecosystem elemental cycling to encourage further empirical quantification. We use a classic ecosystem trophic compartment model as a basis for our analyses but infuse principles from ecological stoichiometry into the analyses of elemental cycling. Using a combined analytical-numerical approach, we compare how predators affect cycling through consumptive effects in which they control the flux of nutrients up trophic chains; through risk effects in which they change the homeostatic elemental balance of herbivore prey which accordingly changes the element ratio herbivores select from plants; and through a combination of both effects. Our analysis reveals that predators can have quantitatively important effects on elemental cycling, relative to a model formalism that excludes predator effects. Furthermore, the feedbacks due to predator nonconsumptive effects often have the quantitatively strongest impact on whole ecosystem elemental stocks, production and efficiency rates, and recycling fluxes by changing the stoichiometric balance of all trophic levels. Our modeling framework predictably shows how bottom-up control by microbes and top-down control by predators on ecosystems become interdependent when top predator effects permeate ecosystems.
Essential trace elements and antioxidant status in relation to severity of HIV in Nigerian patients.
Olaniyi, J A; Arinola, O G
2007-01-01
This study was designed to determine the plasma levels of some antioxidants and trace elements in three severity groups of HIV patients compared with non-HIV-infected controls. The plasma levels of antioxidants (total antioxidant, albumin, bilirubin and uric acid) and trace elements (Mg, Fe, Zn, Mn, Cu, Cr, Cd and Se) were estimated spectrophotometrically in controls and patients with CD4 counts of <200; 200-499 and > or =500 cells/microl. Uric acid and Zn were significantly higher, while vitamin E and all the trace elements (except Zn) were significantly lower in HIV-infected patients compared to healthy controls. The highest level of uric acid was observed in those with CD4 counts of <200 cells/microl. All the trace elements (except Zn) were higher in HIV subjects with a CD4 count of 200-499 cells/microl compared to >500 cells/microl. Only uric acid and Zn showed significant correlation with CD4 count. Based on the results of this study, we recommend routine assessment and appropriate supplementation of antioxidants/trace elements in HIV subjects. This supplementation is hoped to strengthen the immune system and reduce the adverse consequences of HIV- related oxidative stress. Copyright 2007 S. Karger AG, Basel.
Controlling the stoichiometry and doping of semiconductor materials
Albin, David; Burst, James; Metzger, Wyatt; Duenow, Joel; Farrell, Stuart; Colegrove, Eric
2016-08-16
Methods for treating a semiconductor material are provided. According to an aspect of the invention, the method includes annealing the semiconductor material in the presence of a compound that includes a first element and a second element. The first element provides an overpressure to achieve a desired stoichiometry of the semiconductor material, and the second element provides a dopant to the semiconductor material.
NASA Technical Reports Server (NTRS)
1989-01-01
Trade studies plans for a number of elements in the Liquid Rocket Booster (LRB) component of the Space Transportation System (STS) are given in viewgraph form. Some of the elements covered include: avionics/flight control; avionics architecture; thrust vector control studies; engine control electronics; liquid rocket propellants; propellant pressurization systems; recoverable spacecraft; cryogenic tanks; and spacecraft construction materials.
Method and apparatus for characterizing propagation delays of integrated circuit devices
NASA Technical Reports Server (NTRS)
Blaes, Brent R. (Inventor); Buehler, Martin G. (Inventor)
1987-01-01
Propagation delay of a signal through a channel is measured by cyclically generating a first step-wave signal for transmission through the channel to a two-input logic element and a second step-wave signal with a controlled delay to the second input terminal of the logic element. The logic element determines which signal is present first at its input terminals and stores a binary signal indicative of that determination for control of the delay of the second signal which is advanced or retarded for the next cycle until both the propagation delayed first step-wave signal and the control delayed step-wave signal are coincident. The propagation delay of the channel is then determined by measuring the time between the first and second step-wave signals out of the controlled step-wave signal generator.
Autonomous Power System intelligent diagnosis and control
NASA Technical Reports Server (NTRS)
Ringer, Mark J.; Quinn, Todd M.; Merolla, Anthony
1991-01-01
The Autonomous Power System (APS) project at NASA Lewis Research Center is designed to demonstrate the abilities of integrated intelligent diagnosis, control, and scheduling techniques to space power distribution hardware. Knowledge-based software provides a robust method of control for highly complex space-based power systems that conventional methods do not allow. The project consists of three elements: the Autonomous Power Expert System (APEX) for fault diagnosis and control, the Autonomous Intelligent Power Scheduler (AIPS) to determine system configuration, and power hardware (Brassboard) to simulate a space based power system. The operation of the Autonomous Power System as a whole is described and the responsibilities of the three elements - APEX, AIPS, and Brassboard - are characterized. A discussion of the methodologies used in each element is provided. Future plans are discussed for the growth of the Autonomous Power System.
Autonomous power system intelligent diagnosis and control
NASA Technical Reports Server (NTRS)
Ringer, Mark J.; Quinn, Todd M.; Merolla, Anthony
1991-01-01
The Autonomous Power System (APS) project at NASA Lewis Research Center is designed to demonstrate the abilities of integrated intelligent diagnosis, control, and scheduling techniques to space power distribution hardware. Knowledge-based software provides a robust method of control for highly complex space-based power systems that conventional methods do not allow. The project consists of three elements: the Autonomous Power Expert System (APEX) for fault diagnosis and control, the Autonomous Intelligent Power Scheduler (AIPS) to determine system configuration, and power hardware (Brassboard) to simulate a space based power system. The operation of the Autonomous Power System as a whole is described and the responsibilities of the three elements - APEX, AIPS, and Brassboard - are characterized. A discussion of the methodologies used in each element is provided. Future plans are discussed for the growth of the Autonomous Power System.
NASA Technical Reports Server (NTRS)
Nabors, Sammy
2015-01-01
NASA Marshall Space Flight Center (MSFC) developed Ultrasonic Stir Welding (USW) to join large pieces of very high-strength metals such as titanium and Inconel. USW, a solid-state weld process, improves current thermal stir welding processes by adding high-power ultrasonic (HPU) energy at 20 kHz frequency. The addition of ultrasonic energy significantly reduces axial, frictional, and shear forces; increases travel rates; and reduces wear on the stir rod, which results in extended stir rod life. The USW process decouples the heating, stirring, and forging elements found in the friction stir welding process allowing for independent control of each process element and, ultimately, greater process control and repeatability. Because of the independent control of USW process elements, closed-loop temperature control can be integrated into the system so that a constant weld nugget temperature can be maintained during welding.
Hurwitz, H. Jr.; Brooks, H.; Mannal, C.; Payne, J.H.; Luebke, E.A.
1959-03-24
A reactor of the heterogeneous, liquid cooled type is described. This reactor is comprised of a central region of a plurality of vertically disposed elongated tubes surrounded by a region of moderator material. The central region is comprised of a central core surrounded by a reflector region which is surrounded by a fast neutron absorber region, which in turn is surrounded by a slow neutron absorber region. Liquid sodium is used as the primary coolant and circulates through the core which contains the fuel elements. Control of the reactor is accomplished by varying the ability of the reflector region to reflect neutrons back into the core of the reactor. For this purpose the reflector is comprised of moderator and control elements having varying effects on reactivity, the control elements being arranged and actuated by groups to give regulation, shim, and safety control.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Montierth, Leland M.
2016-07-19
The Global Threat Reduction Initiative (GTRI) convert program is developing a high uranium density fuel based on a low enriched uranium (LEU) uranium-molybdenum alloy. Testing of prototypic GTRI fuel elements is necessary to demonstrate integrated fuel performance behavior and scale-up of fabrication techniques. GTRI Enhanced LEU Fuel (ELF) elements based on the ATR-Standard Size elements (all plates fueled) are to be fabricated for testing in the Advanced Test Reactor (ATR). While a specific ELF element design will eventually be provided for detailed analyses and in-core testing, this criticality safety evaluation (CSE) is intended to evaluate a hypothetical ELF element designmore » for criticality safety purposes. Existing criticality analyses have analyzed Standard (HEU) ATR elements from which controls have been derived. This CSE documents analysis that determines the reactivity of the hypothetical ELF fuel elements relative to HEU ATR elements and whether the existing HEU ATR element controls bound the ELF element. The initial calculations presented in this CSE analyzed the original ELF design, now referred to as Mod 0.1. In addition, as part of a fuel meat thickness optimization effort for reactor performance, other designs have been evaluated. As of early 2014 the most current conceptual designs are Mk1A and Mk1B, that were previously referred to as conceptual designs Mod 0.10 and Mod 0.11, respectively. Revision 1 evaluates the reactivity of the ATR HEU Mark IV elements for a comparison with the Mark VII elements.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Rowsell, David Leon
This report documents the Contractor Readiness Assessment (CRA) for TREAT Fuel Movement and Control Rod Drives Isolation. The review followed the approved Plan of Action (POA) and Implementation Plan (IP) using the identified core requirements. The activity was limited scope focusing on the control rod drives functional isolation and fuel element movement. The purpose of this review is to ensure the facility's readiness to move fuel elements thus supporting inspection and functionally isolate the control rod drives to maintain the required shutdown margin.
In vitro cytotoxicity evaluation of elemental ions released from different prosthodontic materials.
Elshahawy, Waleed M; Watanabe, Ikuya; Kramer, Phillip
2009-12-01
This study investigated the cytotoxicity of elemental ions contained in four fixed prosthodontic materials (gold, nickel-chromium, stainless-steel alloys and CAD-CAM ceramics). According to the determination of elements released from prosthodontic materials by using inductively coupled plasma mass spectroscopy, similar amounts of elements Pd, Ag, Zn, Cu, Ni, Cr, Mo, Be, Fe, Al, and K were prepared as salt solutions. Wells with a tenfold higher concentration of the tested elements were used as positive controls, while a well without any tested element was used as a negative control. These salt solutions were tested for cytotoxicity by culturing mouse L-929 fibroblasts in the salt solutions for a 7-day period of incubation. Then, the percentage of viable cells for each element was measured using trypan blue exclusion assay. The data (n=5) were statistically analyzed by ANOVA/Tukey test (p<0.05). The results showed a statistically significant difference for the cytotoxic effect of the tested elements salt solutions. For the released element concentrations the lowest percentage of viable cells (mean+/-SD) was evident with Zn, Cu or Ni indicating that they are the highly toxic elements. Be and Ag were found to be intermediate in cytotoxic effect. Fe, Cr, Mo, Al, Pd or K were found to be the least cytotoxic elements. Zn and Cu released from gold alloys, and Ni released from nickel-chromium alloys, which are commonly used as fixed prosthodontic restorations, show evidence of a high cytotoxic effect on fibroblast cell cultures.
Underpotential deposition-mediated layer-by-layer growth of thin films
Wang, Jia Xu; Adzic, Radoslav R.
2015-05-19
A method of depositing contiguous, conformal submonolayer-to-multilayer thin films with atomic-level control is described. The process involves the use of underpotential deposition of a first element to mediate the growth of a second material by overpotential deposition. Deposition occurs between a potential positive to the bulk deposition potential for the mediating element where a full monolayer of mediating element forms, and a potential which is less than, or only slightly greater than, the bulk deposition potential of the material to be deposited. By cycling the applied voltage between the bulk deposition potential for the mediating element and the material to be deposited, repeated desorption/adsorption of the mediating element during each potential cycle can be used to precisely control film growth on a layer-by-layer basis. This process is especially suitable for the formation of a catalytically active layer on core-shell particles for use in energy conversion devices such as fuel cells.
Phase discriminating capacitive array sensor system
NASA Technical Reports Server (NTRS)
Vranish, John M. (Inventor); Rahim, Wadi (Inventor)
1993-01-01
A phase discriminating capacitive sensor array system which provides multiple sensor elements which are maintained at a phase and amplitude based on a frequency reference provided by a single frequency stabilized oscillator. Sensor signals provided by the multiple sensor elements are controlled by multiple phase control units, which correspond to the multiple sensor elements, to adjust the sensor signals from the multiple sensor elements based on the frequency reference. The adjustment made to the sensor signals is indicated by output signals which indicate the proximity of the object. The output signals may also indicate the closing speed of the object based on the rate of change of the adjustment made, and the edges of the object based on a sudden decrease in the adjustment made.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lentine, Anthony L.; Cox, Jonathan Albert
Methods and systems for stabilizing a resonant modulator include receiving pre-modulation and post-modulation portions of a carrier signal, determining the average power from these portions, comparing an average input power to the average output power, and operating a heater coupled to the modulator based on the comparison. One system includes a pair of input structures, one or more processing elements, a comparator, and a control element. The input structures are configured to extract pre-modulation and post-modulation portions of a carrier signal. The processing elements are configured to determine average powers from the extracted portions. The comparator is configured to comparemore » the average input power and the average output power. The control element operates a heater coupled to the modulator based on the comparison.« less
Lack of Correlation between Metallic Elements Analyzed in Hair by ICP-MS and Autism
ERIC Educational Resources Information Center
De Palma, Giuseppe; Catalani, Simona; Franco, Anna; Brighenti, Maurizio; Apostoli, Pietro
2012-01-01
A cross-sectional case-control study was carried out to evaluate the concentrations of metallic elements in the hair of 44 children with diagnosis of autism and 61 age-balanced controls. Unadjusted comparisons showed higher concentrations of molybdenum, lithium and selenium in autistic children. Logistic regression analysis confirmed the role of…
A hybrid symbolic/finite-element algorithm for solving nonlinear optimal control problems
NASA Technical Reports Server (NTRS)
Bless, Robert R.; Hodges, Dewey H.
1991-01-01
The general code described is capable of solving difficult nonlinear optimal control problems by using finite elements and a symbolic manipulator. Quick and accurate solutions are obtained with a minimum for user interaction. Since no user programming is required for most problems, there are tremendous savings to be gained in terms of time and money.
A/E/C CAD Standard, Release 5.0
2012-12-01
System Control Panels Halon System Inert Gas Smoke/Pressurization Control Egress Requirements Fire Protection System Appendix A ... System Natural Gas System Miter Gates Makeup Air System Appendix A Model File Level/Layer Assignment Tables A54 Discipline: Mechanical Model...SWITCHES Element type: Symbol Electrical: STP14B SURFACE 1X4 STRIP BATTERY Element type: Symbol Electrical: SUBST A
Monolithic optical integrated control circuitry for GaAs MMIC-based phased arrays
NASA Technical Reports Server (NTRS)
Bhasin, K. B.; Ponchak, G. E.; Kascak, T. J.
1985-01-01
Gallium arsenide (GaAs) monolithic microwave integrated circuits (MMIC's) show promise in phased-array antenna applications for future space communications systems. Their efficient usage will depend on the control of amplitude and phase signals for each MMIC element in the phased array and in the low-loss radiofrequency feed. For a phased array contining several MMIC elements a complex system is required to control and feed each element. The characteristics of GaAs MMIC's for 20/30-GHz phased-array systems are discussed. The optical/MMIC interface and the desired characteristics of optical integrated circuits (OIC's) for such an interface are described. Anticipated fabrication considerations for eventual full monolithic integration of optical integrated circuits with MMIC's on a GaAs substrate are presented.
Institutionalising Human Governance Determinant: Steering Organizations towards Sustainability
NASA Astrophysics Data System (ADS)
Muhamad Hanapiyah, Zulkefli; Daud, Salina; Abdullah, Wan Mohammad Taufik Wan
2016-03-01
This paper discusses past researches on human governance elements. Eight elements of human governance are proposed in this paper: leadership, integrity, religiosity, spirituality, culture, recruitment, training and internal control policy. Empirical study shall be conducted in the future study to confirm the eight elements of human governance proposed in this paper. It is expected that these elements may enhance the human governance practice in the organizations.
Fire and the Related Effects of Nuclear Explosions. 1982 Asilomar Conference,
1982-11-01
SRT International 333 Ravenswood Ave. Menlo Park, CA 94025 F2A Work Unit 2563F II. CONTROLLING OFFICE NAME AND AOoReSS US. REPORT OATS Federal...and Scope: 1. Define the events and modules to be used in the Urban Fire Demonstration Model along with appropriate data elements, control and data...1) a specific control structure to sequence and organize the various computational V- 9 elements of an interactive simulation, and (2) emphasis
Flexible Models for Solar Sail Control
NASA Technical Reports Server (NTRS)
Weaver Smith, Suzanne; Song, Haiping; Baker, John R.; Black, Jonathan; Muheim, Danniella M.
2005-01-01
Solar sails employ a unique form of propulsion, gaining momentum from incident and reflected photons. However, the momentum transferred by an individual photon is extremely small. Consequently, a solar sail must have an extremely large surface area and also be extremely light. The flexibility of the sail then must be considered when designing or evaluating control laws. In this paper, solar sail flexibility and its influence on control effectiveness is considered using idealized two-dimensional models to represent physical phenomena rather than a specific design. Differential equations of motion are derived for a distributed parameter model of a flexible solar sail idealized as a rotating central hub with two opposing flexible booms. This idealization is appropriate for solar sail designs in which the vibrational modes of the sail and supporting booms move together allowing the sail mass to be distributed along the booms in the idealized model. A reduced analytical model of the flexible response is considered. Linear feedback torque control is applied at the central hub. Two translational disturbances and a torque disturbance also act at the central hub representing the equivalent effect of deflecting sail shape about a reference line. Transient simulations explore different control designs and their effectiveness for controlling orientation, for reducing flexible motion and for disturbance rejection. A second model also is developed as a two-dimensional "pathfinder" model to calculate the effect of solar sail shape on the resultant thrust, in-plane force and torque at the hub. The analysis is then extended to larger models using the finite element method. The finite element modeling approach is verified by comparing results from a two-dimensional finite element model with those from the analytical model. The utility of the finite element modeling approach for this application is then illustrated through examples based on a full finite element model.
Using Agent-Based Modeling to Enhance System-Level Real-time Control of Urban Stormwater Systems
NASA Astrophysics Data System (ADS)
Rimer, S.; Mullapudi, A. M.; Kerkez, B.
2017-12-01
The ability to reduce combined-sewer overflow (CSO) events is an issue that challenges over 800 U.S. municipalities. When the volume of a combined sewer system or wastewater treatment plant is exceeded, untreated wastewater then overflows (a CSO event) into nearby streams, rivers, or other water bodies causing localized urban flooding and pollution. The likelihood and impact of CSO events has only exacerbated due to urbanization, population growth, climate change, aging infrastructure, and system complexity. Thus, there is an urgent need for urban areas to manage CSO events. Traditionally, mitigating CSO events has been carried out via time-intensive and expensive structural interventions such as retention basins or sewer separation, which are able to reduce CSO events, but are costly, arduous, and only provide a fixed solution to a dynamic problem. Real-time control (RTC) of urban drainage systems using sensor and actuator networks has served as an inexpensive and versatile alternative to traditional CSO intervention. In particular, retrofitting individual stormwater elements for sensing and automated active distributed control has been shown to significantly reduce the volume of discharge during CSO events, with some RTC models demonstrating a reduction upwards of 90% when compared to traditional passive systems. As more stormwater elements become retrofitted for RTC, system-level RTC across complete watersheds is an attainable possibility. However, when considering the diverse set of control needs of each of these individual stormwater elements, such system-level RTC becomes a far more complex problem. To address such diverse control needs, agent-based modeling is employed such that each individual stormwater element is treated as an autonomous agent with a diverse decision making capabilities. We present preliminary results and limitations of utilizing the agent-based modeling computational framework for the system-level control of diverse, interacting stormwater elements.
Kazi, Tasneem Gul; Wadhwa, Sham Kumar; Afridi, Hassan Imran; Talpur, Farah Naz; Tuzen, Mustafa; Baig, Jameel Ahmed
2015-05-01
There is a compelling evidence in support of negative associations between essential trace and toxic elements in different types of cancer. The aim of the present study was to investigate the relationship between carcinogenic (As, Cd, Ni) and anti-carcinogenic (Se, Zn) trace elements in scalp hair samples of different male cancerous patients (esophagus, lung, mouth, and urinary bladder). For comparative purposes, the scalp hair samples of healthy males of the same age group (ranged 35-65 years) as controls were analyzed. Both controls and patients have the same socioeconomic status, localities, dietary habits, and smoking locally made cigarette. The scalp hair samples were oxidized by 65% nitric acid: 30% hydrogen peroxide (2:1) ratio in microwave oven followed by atomic absorption spectrometry. The validity and accuracy of the methodology were checked using certified reference material of human hair BCR 397. The mean concentrations of As, Cd, and Ni were found to be significantly higher in scalp hair samples of patients having different cancers as compared to the controls, while reverse results were obtained in the case of Se and Zn levels (p < 0.01). The study revealed that the carcinogenic processes are significantly affecting the trace elements burden and mutual interaction of essential trace and toxic elements in the cancerous patients.
Hanging drop crystal growth apparatus and method
NASA Technical Reports Server (NTRS)
Carter, Daniel C. (Inventor); Smith, Robbie E. (Inventor)
1989-01-01
An apparatus (10) is constructed having a cylindrical enclosure (16) within which a disc-shaped wicking element (18) is positioned. A well or recess (22) is cut into an upper side (24) of this wicking element, and a glass cover plate or slip (28) having a protein drop disposed thereon is sealably positioned on the wicking element (18), with drop (12) being positioned over well or recess (22). A flow of control fluid is generated by a programmable gradient former (16), with this control fluid having a vapor pressure that is selectively variable. This flow of control fluid is coupled to the wicking element (18) where control fluid vapor diffusing from walls (26) of the recess (22) is exposed to the drop (12), forming a vapor pressure gradient between the drop (12) and the control fluid vapor. Initially, this gradient is adjusted to draw solvent from the drop (12) at a relatively high rate, and as the critical supersaturation point is approached (the point at which crystal nucleation occurs), the gradient is reduced to more slowly draw solvent from the drop (12). This allows discrete protein molecules more time to orient themselves into an ordered crystalline lattice, producing protein crystals which, when processed by X-ray crystallography, possess a high degree of resolution.
Structural analysis of natural textures.
Vilnrotter, F M; Nevatia, R; Price, K E
1986-01-01
Many textures can be described structurally, in terms of the individual textural elements and their spatial relationships. This paper describes a system to generate useful descriptions of natural textures in these terms. The basic approach is to determine an initial, partial description of the elements using edge features. This description controls the extraction of the texture elements. The elements are grouped by type, and spatial relationships between elements are computed. The descriptions are shown to be useful for recognition of the textures, and for reconstruction of periodic textures.
Ecosystem Succession and Nutrient Retention: A Hypothesis
ERIC Educational Resources Information Center
Vitousek, Peter M.; Reiners, William A.
1975-01-01
A hypothesis is presented for the regulation of elemental losses from terrestrial ecosystems. Losses of elements are controlled by the net increment of biomass growth and the elemental composition of this net increment. According to this hypothesis, loss rates are highest in early succession and in steady state ecosystems. (Author/EB)
A finite element based method for solution of optimal control problems
NASA Technical Reports Server (NTRS)
Bless, Robert R.; Hodges, Dewey H.; Calise, Anthony J.
1989-01-01
A temporal finite element based on a mixed form of the Hamiltonian weak principle is presented for optimal control problems. The mixed form of this principle contains both states and costates as primary variables that are expanded in terms of elemental values and simple shape functions. Unlike other variational approaches to optimal control problems, however, time derivatives of the states and costates do not appear in the governing variational equation. Instead, the only quantities whose time derivatives appear therein are virtual states and virtual costates. Also noteworthy among characteristics of the finite element formulation is the fact that in the algebraic equations which contain costates, they appear linearly. Thus, the remaining equations can be solved iteratively without initial guesses for the costates; this reduces the size of the problem by about a factor of two. Numerical results are presented herein for an elementary trajectory optimization problem which show very good agreement with the exact solution along with excellent computational efficiency and self-starting capability. The goal is to evaluate the feasibility of this approach for real-time guidance applications. To this end, a simplified two-stage, four-state model for an advanced launch vehicle application is presented which is suitable for finite element solution.
Williamson, Matthew M.; Pratt, Gill A.
1999-06-08
The invention provides an elastic actuator consisting of a motor and a motor drive transmission connected at an output of the motor. An elastic element is connected in series with the motor drive transmission, and this elastic element is positioned to alone support the full weight of any load connected at an output of the actuator. A single force transducer is positioned at a point between a mount for the motor and an output of the actuator. This force transducer generates a force signal, based on deflection of the elastic element, that indicates force applied by the elastic element to an output of the actuator. An active feedback force control loop is connected between the force transducer and the motor for controlling the motor. This motor control is based on the force signal to deflect the elastic element an amount that produces a desired actuator output force. The produced output force is substantially independent of load motion. The invention also provides a torsional spring consisting of a flexible structure having at least three flat sections each connected integrally with and extending radially from a central section. Each flat section extends axially along the central section from a distal end of the central section to a proximal end of the central section.
Reliability modelling and analysis of a multi-state element based on a dynamic Bayesian network
NASA Astrophysics Data System (ADS)
Li, Zhiqiang; Xu, Tingxue; Gu, Junyuan; Dong, Qi; Fu, Linyu
2018-04-01
This paper presents a quantitative reliability modelling and analysis method for multi-state elements based on a combination of the Markov process and a dynamic Bayesian network (DBN), taking perfect repair, imperfect repair and condition-based maintenance (CBM) into consideration. The Markov models of elements without repair and under CBM are established, and an absorbing set is introduced to determine the reliability of the repairable element. According to the state-transition relations between the states determined by the Markov process, a DBN model is built. In addition, its parameters for series and parallel systems, namely, conditional probability tables, can be calculated by referring to the conditional degradation probabilities. Finally, the power of a control unit in a failure model is used as an example. A dynamic fault tree (DFT) is translated into a Bayesian network model, and subsequently extended to a DBN. The results show the state probabilities of an element and the system without repair, with perfect and imperfect repair, and under CBM, with an absorbing set plotted by differential equations and verified. Through referring forward, the reliability value of the control unit is determined in different kinds of modes. Finally, weak nodes are noted in the control unit.
Quasi-monolithic tunable optical resonator
NASA Technical Reports Server (NTRS)
Arbore, Mark (Inventor); Tapos, Francisc (Inventor)
2003-01-01
An optical resonator has a piezoelectric element attached to a quasi-monolithic structure. The quasi-monolithic structure defines an optical path. Mirrors attached to the structure deflect light along the optical path. The piezoelectric element controllably strains the quasi-monolithic structure to change a length of the optical path by about 1 micron. A first feedback loop coupled to the piezoelectric element provides fine control over the cavity length. The resonator may include a thermally actuated spacer attached to the cavity and a mirror attached to the spacer. The thermally actuated spacer adjusts the cavity length by up to about 20 microns. A second feedback loop coupled to the sensor and heater provides a coarse control over the cavity length. An alternative embodiment provides a quasi-monolithic optical parametric oscillator (OPO). This embodiment includes a non-linear optical element within the resonator cavity along the optical path. Such an OPO configuration is broadly tunable and capable of mode-hop free operation for periods of 24 hours or more.
NASA Technical Reports Server (NTRS)
Diner, Daniel B. (Inventor); Venema, Steven C. (Inventor)
1991-01-01
A system for real-time video image display for robotics or remote-vehicle teleoperation is described that has at least one robot arm or remotely operated vehicle controlled by an operator through hand-controllers, and one or more television cameras and optional lighting element. The system has at least one television monitor for display of a television image from a selected camera and the ability to select one of the cameras for image display. Graphics are generated with icons of cameras and lighting elements for display surrounding the television image to provide the operator information on: the location and orientation of each camera and lighting element; the region of illumination of each lighting element; the viewed region and range of focus of each camera; which camera is currently selected for image display for each monitor; and when the controller coordinate for said robot arms or remotely operated vehicles have been transformed to correspond to coordinates of a selected or nonselected camera.
Composite video and graphics display for camera viewing systems in robotics and teleoperation
NASA Technical Reports Server (NTRS)
Diner, Daniel B. (Inventor); Venema, Steven C. (Inventor)
1993-01-01
A system for real-time video image display for robotics or remote-vehicle teleoperation is described that has at least one robot arm or remotely operated vehicle controlled by an operator through hand-controllers, and one or more television cameras and optional lighting element. The system has at least one television monitor for display of a television image from a selected camera and the ability to select one of the cameras for image display. Graphics are generated with icons of cameras and lighting elements for display surrounding the television image to provide the operator information on: the location and orientation of each camera and lighting element; the region of illumination of each lighting element; the viewed region and range of focus of each camera; which camera is currently selected for image display for each monitor; and when the controller coordinate for said robot arms or remotely operated vehicles have been transformed to correspond to coordinates of a selected or nonselected camera.
NASA Technical Reports Server (NTRS)
Bagdigian, Robert M.
2009-01-01
Visions of lunar outposts often depict a collection of fixed elements such as pressurized habitats, in and around which human inhabitants spend the large majority of their surface stay time. In such an outpost, an efficient deployment of environmental control and life support equipment can be achieved by centralizing certain functions within one or a minimum number of habitable elements and relying on the exchange of gases and liquids between elements via atmosphere ventilation and plumbed interfaces. However, a rigidly fixed outpost can constrain the degree to which the total lunar landscape can be explored. The capability to enable widespread access across the landscape makes a lunar architecture with a high degree of surface mobility attractive. Such mobility presents unique challenges to the efficient deployment of environmental control and life support functions in multiple elements that may for long periods of time be operated independently. This paper describes some of those anticipated challenges.
Finite element solution of optimal control problems with inequality constraints
NASA Technical Reports Server (NTRS)
Bless, Robert R.; Hodges, Dewey H.
1990-01-01
A finite-element method based on a weak Hamiltonian form of the necessary conditions is summarized for optimal control problems. Very crude shape functions (so simple that element numerical quadrature is not necessary) can be used to develop an efficient procedure for obtaining candidate solutions (i.e., those which satisfy all the necessary conditions) even for highly nonlinear problems. An extension of the formulation allowing for discontinuities in the states and derivatives of the states is given. A theory that includes control inequality constraints is fully developed. An advanced launch vehicle (ALV) model is presented. The model involves staging and control constraints, thus demonstrating the full power of the weak formulation to date. Numerical results are presented along with total elapsed computer time required to obtain the results. The speed and accuracy in obtaining the results make this method a strong candidate for a real-time guidance algorithm.
Interconnecting network for switching data packets and method for switching data packets
Benner, Alan Frederic; Minkenberg, Cyriel Johan Agnes; Stunkel, Craig Brian
2010-05-25
The interconnecting network for switching data packets, having data and flow control information, comprises a local packet switch element (S1) with local input buffers (I(1,1) . . . I(1,y)) for buffering the incoming data packets, a remote packet switch element (S2) with remote input buffers (I(2,1) . . . I(2,y)) for buffering the incoming data packets, and data lines (L) for interconnecting the local and the remote packet switch elements (S1, S2). The interconnecting network further comprises a local and a remote arbiter (A1, A2) which are connected via control lines (CL) to the input buffers (I(1,1) . . . I(1,y), I(2,1) . . . I(2,y)), and which are formed such that they can provide that the flow control information is transmitted via the data lines (L) and the control lines (CL).
Islam, Md Rabiul; Islam, Md Reazul; Shalahuddin Qusar, M M A; Islam, Mohammad Safiqul; Kabir, Md Humayun; Mustafizur Rahman, G K M; Islam, Md Saiful; Hasnat, Abul
2018-04-10
Major depressive disorder (MDD) is a mixed disorder with the highly irregular course, inconsistent response to treatment and has no well-known mechanism for the pathophysiology. Major causes of depression are genetic, neurobiological, and environmental. However, over the past few years, altered serum levels of macro-minerals (MM) and trace elements (TE) have been recognized as major causative factors to the pathogenesis of many mental disorders. The purpose of this study was to determine the serum levels of MM (calcium and magnesium) and TE (copper, iron, manganese, selenium, and zinc) in MDD patients and find out their associations with depression risk. This prospective case-control study recruited 247 patients and 248 healthy volunteers matched by age and sex. The serum levels of MM and TE were analyzed by atomic absorption spectroscopy (AAS). Statistical analysis was performed with independent sample t-tests and Pearson's correlation test. We found significantly decreased concentrations of calcium and magnesium, iron, manganese, selenium, and zinc in MDD patients compared with control subjects (p < 0.05). But the concentration of copper was significantly increased in the patients than control subjects (p < 0.05). Data obtained from different inter-element relations in MDD patients and control subjects strongly suggest that there is a disturbance in the element homeostasis. Our study suggests that altered serum concentrations of MM and TE are major contributing factors for the pathogenesis of MDD. Alterations of these elements in serum levels of MDD patients arise independently and they may provide a prognostic tool for the assessment of depression risk.
Equine grass sickness in Scotland: A case-control study of environmental geochemical risk factors.
Wylie, C E; Shaw, D J; Fordyce, F M; Lilly, A; Pirie, R S; McGorum, B C
2016-11-01
We hypothesised that the apparent geographical distribution of equine grass sickness (EGS) is partly attributable to suboptimal levels of soil macro- and trace elements in fields where EGS occurs. If proven, altering levels of particular elements could be used to reduce the risk of EGS. To determine whether the geographical distribution of EGS cases in eastern Scotland is associated with the presence or absence of particular environmental chemical elements. Retrospective time-matched case-control study. This study used data for 455 geo-referenced EGS cases and 910 time-matched controls in eastern Scotland, and geo-referenced environmental geochemical data from the British Geological Survey Geochemical Baseline Survey of the Environment stream sediment (G-BASE) and the James Hutton Institute, National Soil Inventory of Scotland (NSIS) datasets. Multivariable statistical analyses identified clusters of three main elements associated with cases from (i) the G-BASE dataset - higher environmental Ti and lower Zn, and (ii) the NSIS dataset - higher environmental Ti and lower Cr. There was also some evidence from univariable analyses for lower Al, Cd, Cu, Ni and Pb and higher Ca, K, Mo, Na and Se environmental concentrations being associated with a case. Results were complicated by a high degree of correlation between most geochemical elements. The work presented here would appear to reflect soil- not horse-level risk factors for EGS, but due to the complexity of the correlations between elements, further work is required to determine whether these associations reflect causality, and consequently whether interventions to alter concentrations of particular elements in soil, or in grazing horses, could potentially reduce the risk of EGS. The effect of chemical elements on the growth of those soil microorganisms implicated in EGS aetiology also warrants further study. © 2015 The The Authors Equine Veterinary Journal © 2015 EVJ Ltd.
The effects of elemental diet and subsequent food reintroduction on rheumatoid arthritis.
Kavanaghi, R; Workman, E; Nash, P; Smith, M; Hazleman, B L; Hunter, J O
1995-03-01
The role of diet in rheumatoid arthritis (RA) remains controversial and there have been no controlled studies on the use of elemental diet in the treatment of RA. Elemental diet is an hypoallergenic protein-free artificial diet consisting of essential amino acids, glucose, trace elements and vitamins. This study was carried out to assess the role of elemental diet and subsequent food reintroduction in RA. Elemental diet (E028) (and a small number of foods) was given to 24 patients with definite RA in order to induce a remission and then foods were gradually introduced. Where a food was suspected of causing symptoms it was removed from the diet. Twenty-three control patients supplemented their usual diet with E028. After the elemental diet there was a statistically significant improvement in the diet group in grip strength (P = 0.008) and Ritchie score (P = 0.006) but not in ESR, CRP, thermographic joint score or functional score. The diet group lost more weight than the control group and this correlated with the improvement in grip strength. This improvement was not present following food reintroduction. As the improvements took place in more subjective disease parameters and because of the difficulties in adequately blinding studies of diet in arthritis, a placebo effect must be considered. There was a high default rate, only 38% of those patients originally enrolled completed the study. In conclusion, this study shows that elemental diet can cause an improvement in a number of disease parameters in RA but this is not sustained by an individualized diet. It also illustrates some of the difficulties involved in the study of diet in arthritis.
Multivariate Analysis of the Cotton Seed Ionome Reveals a Shared Genetic Architecture
Pauli, Duke; Ziegler, Greg; Ren, Min; Jenks, Matthew A.; Hunsaker, Douglas J.; Zhang, Min; Baxter, Ivan; Gore, Michael A.
2018-01-01
To mitigate the effects of heat and drought stress, a better understanding of the genetic control of physiological responses to these environmental conditions is needed. To this end, we evaluated an upland cotton (Gossypium hirsutum L.) mapping population under water-limited and well-watered conditions in a hot, arid environment. The elemental concentrations (ionome) of seed samples from the population were profiled in addition to those of soil samples taken from throughout the field site to better model environmental variation. The elements profiled in seeds exhibited moderate to high heritabilities, as well as strong phenotypic and genotypic correlations between elements that were not altered by the imposed irrigation regimes. Quantitative trait loci (QTL) mapping results from a Bayesian classification method identified multiple genomic regions where QTL for individual elements colocalized, suggesting that genetic control of the ionome is highly interrelated. To more fully explore this genetic architecture, multivariate QTL mapping was implemented among groups of biochemically related elements. This analysis revealed both additional and pleiotropic QTL responsible for coordinated control of phenotypic variation for elemental accumulation. Machine learning algorithms that utilized only ionomic data predicted the irrigation regime under which genotypes were evaluated with very high accuracy. Taken together, these results demonstrate the extent to which the seed ionome is genetically interrelated and predictive of plant physiological responses to adverse environmental conditions. PMID:29437829
Underpotential deposition-mediated layer-by-layer growth of thin films
Wang, Jia Xu; Adzic, Radoslav R.
2017-06-27
A method of depositing contiguous, conformal submonolayer-to-multilayer thin films with atomic-level control is described. The process involves electrochemically exchanging a mediating element on a substrate with a noble metal film by alternatingly sweeping potential in forward and reverse directions for a predetermined number of times in an electrochemical cell. By cycling the applied voltage between the bulk deposition potential for the mediating element and the material to be deposited, repeated desorption/adsorption of the mediating element during each potential cycle can be used to precisely control film growth on a layer-by-layer basis.
METHOD AND APPARATUS FOR CONTROLLING NEUTRON DENSITY
Wigner, E.P.; Young, G.J.; Weinberg, A.M.
1961-06-27
A neutronic reactor comprising a moderator containing uniformly sized and spaced channels and uniformly dimensioned fuel elements is patented. The fuel elements have a fissionable core and an aluminum jacket. The cores and the jackets of the fuel elements in the central channels of the reactor are respectively thinner and thicker than the cores and jackets of the fuel elements in the remainder of the reactor, producing a flattened flux.
Modal Testing of Seven Shuttle Cargo Elements for Space Station
NASA Technical Reports Server (NTRS)
Kappus, Kathy O.; Driskill, Timothy C.; Parks, Russel A.; Patterson, Alan (Technical Monitor)
2001-01-01
From December 1996 to May 2001, the Modal and Control Dynamics Team at NASA's Marshall Space Flight Center (MSFC) conducted modal tests on seven large elements of the International Space Station. Each of these elements has been or will be launched as a Space Shuttle payload for transport to the International Space Station (ISS). Like other Shuttle payloads, modal testing of these elements was required for verification of the finite element models used in coupled loads analyses for launch and landing. The seven modal tests included three modules - Node, Laboratory, and Airlock, and four truss segments - P6, P3/P4, S1/P1, and P5. Each element was installed and tested in the Shuttle Payload Modal Test Bed at MSFC. This unique facility can accommodate any Shuttle cargo element for modal test qualification. Flexure assemblies were utilized at each Shuttle-to-payload interface to simulate a constrained boundary in the load carrying degrees of freedom. For each element, multiple-input, multiple-output burst random modal testing was the primary approach with controlled input sine sweeps for linearity assessments. The accelerometer channel counts ranged from 252 channels to 1251 channels. An overview of these tests, as well as some lessons learned, will be provided in this paper.
MCAT elements and the TEF-1 family of transcription factors in muscle development and disease.
Yoshida, Tadashi
2008-01-01
MCAT elements are located in the promoter-enhancer regions of cardiac, smooth, and skeletal muscle-specific genes including cardiac troponin T, beta-myosin heavy chain, smooth muscle alpha-actin, and skeletal alpha-actin, and play a key role in the regulation of these genes during muscle development and disease. The binding factors of MCAT elements are members of the transcriptional enhancer factor-1 (TEF-1) family. However, it has not been fully understood how these transcription factors confer cell-specific expression in muscle, because their expression patterns are relatively broad. Results of recent studies revealed multiple mechanisms whereby TEF-1 family members control MCAT element-dependent muscle-specific gene expression, including posttranslational modifications of TEF-1 family members, the presence of muscle-selective TEF-1 cofactors, and cell-selective control of TEF-1 accessibility to MCAT elements. In addition, of particular interest, recent studies regarding MCAT element-dependent transcription of the myocardin gene and the smooth muscle alpha-actin gene in muscle provide evidence for the transcriptional diversity among distinct cell types and subtypes. This article summarizes the role of MCAT elements and the TEF-1 family of transcription factors in muscle development and disease, and reviews recent progress in our understanding of the transcriptional regulatory mechanisms involved in MCAT element-dependent muscle-specific gene expression.
Isama, Kazuo; Kawakami, Tsuyoshi; Nishimura, Tetsuji
2011-01-01
Harmful elements are used as stabilizers and colorants in synthetic resin products. Accidental ingestion of harmful elements from such synthetic resins by infants is a dangerous health hazard. The Japanese Food Sanitation Law and the International Standard ISO 8124-3 "Safety of toys-Part 3: Migration of certain elements" control the levels of migrated harmful elements, such as lead or cadmium, from infants toys. However, the levels of migrated harmful elements from household products that are not infants toys are not controlled, since they are not covered by the law or standard. Therefore, we investigated the level of eight harmful elements (antimony, arsenic, barium, cadmium, chromium, lead, mercury and selenium) migrated from household products made of synthetic resin that infants may swallow by mistake. The extraction test of ISO 8124-3: 2010 was executed in 135 products (total 150 specimens), and the concentration of these elements was measured by inductively coupled plasma mass spectroscopy (ICP-MS). As a result, 1810 mg/kg and 1660 mg/kg of lead, exceeding the maximum acceptable level of the ISO standard, migrated from two products. In addition, lead and/or chromium at levels more than 1/10 of the maximum acceptable levels of the ISO standard migrated from four products. Household products that infants may swallow by mistake should ideally not release harmful elements such as lead and chromium.
Kitamura, Hiroki; Dahlan, Astryd Viandila; Tian, Yu; Shimaoka, Takayuki; Yamamoto, Takashi; Takahashi, Fumitake
2018-05-12
Impacts of secondary generated minerals on mineralogical and physical immobilization of toxic elements were investigated for chelate-treated air pollution control (APC) fly ash of a municipal solid waste incinerator. Scanning electron microscope (SEM) observation showed that ettringite was generated after the moistening treatment with/without chelate. Although ettringite can incorporate toxic elements into its structure, elemental analysis by energy dispersive X-ray could not find concentrated points of toxic elements in ettringite structure. This implies that mineralogical immobilization of toxic element by the encapsulation to ettringite structure seems to be limited. Physical immobilization was also investigated by SEM observation of the same APC fly ash particles before and after the moistening treatment. The transfer of soluble elements was inhibited only when insoluble minerals such as gypsum were generated and covered the surface of fly ash particles. Neoformed insoluble minerals prevented soluble elements from leaching and transfer. However, such physical immobilization seems to be limited because insoluble mineral formation with surface coverage was monitored only one time of more than 20 observations. Although uncertainty owing to limited samples with limited observations should be considered, this study concludes that mineralogical and physical immobilization of toxic elements by secondary minerals is limited although secondary minerals are always generated on the surface of APC fly ash particles during chelate treatment.
On a useful functional representation of control system structure
NASA Technical Reports Server (NTRS)
Malchow, Harvey L.
1988-01-01
An alternative structure for control systems is proposed. The structure is represented by a three-element block diagram and three functional definitions. It is argued that the three functional elements form a canonical set. The set includes the functions description, estimation and control. General overlay of the structure on parallel state and nested-state control systems is discussed. Breakdown of two real nested-state control systems into the proposed functional format is displayed. Application of the process to the mapping of complex control systems R and D efforts is explained with the Mars Rover Sample and Return mission as an example. A previous application of this basic functional structure to Space Station performance requirements organization is discussed.
Photovoltaic Powering And Control System For Electrochromic Windows
Schulz, Stephen C.; Michalski, Lech A.; Volltrauer, Hermann N.; Van Dine, John E.
2000-04-25
A sealed insulated glass unit is provided with an electrochromic device for modulating light passing through the unit. The electrochromic device is controlled from outside the unit by a remote control electrically unconnected to the device. Circuitry within the unit may be magnetically controlled from outside. The electrochromic device is powered by a photovoltaic cells. The photovoltaic cells may be positioned so that at least a part of the light incident on the cell passes through the electrochromic device, providing a form of feedback control. A variable resistance placed in parallel with the electrochromic element is used to control the response of the electrochromic element to changes in output of the photovoltaic cell.
NASA Astrophysics Data System (ADS)
Chróścielewski, Jacek; Schmidt, Rüdiger; Eremeyev, Victor A.
2018-05-01
This paper addresses modeling and finite element analysis of the transient large-amplitude vibration response of thin rod-type structures (e.g., plane curved beams, arches, ring shells) and its control by integrated piezoelectric layers. A geometrically nonlinear finite beam element for the analysis of piezolaminated structures is developed that is based on the Bernoulli hypothesis and the assumptions of small strains and finite rotations of the normal. The finite element model can be applied to static, stability, and transient analysis of smart structures consisting of a master structure and integrated piezoelectric actuator layers or patches attached to the upper and lower surfaces. Two problems are studied extensively: (i) FE analyses of a clamped semicircular ring shell that has been used as a benchmark problem for linear vibration control in several recent papers are critically reviewed and extended to account for the effects of structural nonlinearity and (ii) a smart circular arch subjected to a hydrostatic pressure load is investigated statically and dynamically in order to study the shift of bifurcation and limit points, eigenfrequencies, and eigenvectors, as well as vibration control for loading conditions which may lead to dynamic loss of stability.
Selective catalyst reduction light-off strategy
Gonze, Eugene V [Pinckney, MI
2011-10-18
An emissions control system includes a temperature determination module and an emissions control module. The temperature determination module determines a first temperature of a heater element of a diesel particulate filter (DPF) assembly in an exhaust system and determines a second temperature of a catalyst of the DPF assembly. The emissions control module selectively activates the heater element, selectively initiates a predefined combustion process in an engine based upon the first temperature, and selectively starts a reductant injection process based upon the second temperature.
NASA Technical Reports Server (NTRS)
Cox, D. E.; Groom, N. J.
1994-01-01
An implementation of a decoupled, single-input/single-output control approach for a large angle magnetic suspension test fixture is described. Numerical and experimental results are presented. The experimental system is a laboratory model large gap magnetic suspension system which provides five degree-of-freedom control of a cylindrical suspended element. The suspended element contains a core composed of permanent magnet material and is levitated above five electromagnets mounted in a planar array.
A temperature control design for a tapered element oscillating microbalance sensing surface
NASA Technical Reports Server (NTRS)
1982-01-01
A design study is presented which shows that a tapered element oscillating microbalance can be adapted for temperature control under space application by mating with multistage thermoelectric coolers in such a way that an integral structure evolves. The control of the temperature of the sensing surface can be achieved in a number of ways. An indirect method which uses a measurement of the absorbed power is recommended. The design goals can be met if a relaxation of the power requirement can be considered.
Advanced hybrid particulate collector and method of operation
Miller, Stanley J.
1999-01-01
A device and method for controlling particulate air pollutants of the present invention combines filtration and electrostatic collection devices. The invention includes a chamber housing a plurality of rows of filter elements. Between each row of filter elements is a grounded plate. Between the grounded plates and the filter elements are electrode grids for creating electrostatic precipitation zones between each row of filter elements. In this way, when the filter elements are cleaned by pulsing air in a reverse direction, the dust removed from the bags will collect in the electrostatic precipitation zones rather than on adjacent filter elements.
Advanced hybrid particulate collector and method of operation
Miller, S.J.
1999-08-17
A device and method for controlling particulate air pollutants of the present invention combines filtration and electrostatic collection devices. The invention includes a chamber housing a plurality of rows of filter elements. Between each row of filter elements is a grounded plate. Between the grounded plates and the filter elements are electrode grids for creating electrostatic precipitation zones between each row of filter elements. In this way, when the filter elements are cleaned by pulsing air in a reverse direction, the dust removed from the bags will collect in the electrostatic precipitation zones rather than on adjacent filter elements. 12 figs.
Micro faraday-element array detector for ion mobility spectroscopy
Gresham, Christopher A [Albuquerque, NM; Rodacy, Phillip J [Albuquerque, NM; Denton, M Bonner [Tucson, AZ; Sperline, Roger [Tucson, AZ
2004-10-26
An ion mobility spectrometer includes a drift tube having a collecting surface covering a collecting area at one end of the tube. The surface comprises a plurality of closely spaced conductive elements on a non-conductive substrate, each conductive element being electrically insulated from each other element. A plurality of capacitive transimpedance amplifiers (CTIA) adjacent the collecting surface are electrically connected to the plurality of elements, so charge from an ion striking an element is transferred to the capacitor of the connected CTIA. A controller counts the charge on the capacitors over a period of time.
Risk Control Through the Use of Procedures - A Method for Evaluating the Change in Risk
NASA Technical Reports Server (NTRS)
Praino, Gregory; Sharit, Joseph
2010-01-01
Organizations use procedures to influence or control the behavior of their workers, but often have no basis for determining whether an additional rule, or procedural control will be beneficial. This paper outlines a proposed method for determining if the addition or removal of procedural controls will impact the occurrences of critical consequences. The proposed method focuses on two aspects: how valuable the procedural control is, based on the inevitability of the consequence and the opportunity to intervene; and how likely the control is to fail, based on five procedural design elements that address how well the rule or control has been Defined, Assigned, Trained, Organized and Monitored-referred to as the DATOM elements
Childers, Delma S; Kadosh, David
2015-01-01
Candida albicans is the most frequently isolated human fungal pathogen and can cause a range of mucosal and systemic infections in immunocompromised individuals. Morphogenesis, the ability to undergo a reversible transition from budding yeast to elongated filaments, is an essential virulence trait. The yeast-to-filament transition is associated with expression of genes specifically important for filamentation as well as other virulence-related processes, and is controlled, in part, by the key transcriptional regulators Nrg1 and Ume6. Both of these regulators are themselves controlled at the transcriptional level by filament-inducing environmental cues, although little is known about how this process occurs. In order to address this question and determine whether environmental signals regulate transcription of UME6 and NRG1 via distinct and/or common promoter elements, we performed promoter deletion analyses. Strains bearing promoter deletion constructs were induced to form filaments in YEPD plus 10% serum at 37°C, Spider medium (nitrogen and carbon starvation) and/or Lee's medium pH 6.8 (neutral pH) and reporter gene expression was measured. In the NRG1 promoter we identified several distinct condition-specific response elements for YEPD plus 10% serum at 37°C and Spider medium. In the UME6 promoter we also identified response elements for YEPD plus 10% serum at 37°C. While a few of these elements are distinct, others overlap with those which respond to Lee's pH 6.8 medium. Consistent with UME6 possessing a very long 5' UTR, many response elements in the UME6 promoter are located significantly upstream from the coding sequence. Our data indicate that certain distinct condition-specific elements can control expression of C. albicans UME6 and NRG1 in response to key filament-inducing environmental cues. Because C. albicans encounters a variety of host microenvironments during infection, our results suggest that UME6 and NRG1 expression can be differentially modulated by multiple signaling pathways to control filamentation and virulence in vivo.
Adhesion and friction of iron-base binary alloys in contact with silicon carbide in vacuum
NASA Technical Reports Server (NTRS)
Miyoshi, K.; Buckley, D. H.
1980-01-01
Single pass sliding friction experiments were conducted with various iron base binary alloys (alloying elements were Ti, Cr, Mn, Ni, Rh, and W) in contact with a single crystal silicon carbide /0001/ surface in vacuum. Results indicate that atomic size and concentration of alloying elements play an important role in controlling adhesion and friction properties of iron base binary alloys. The coefficient of friction generally increases with an increase in solute concentration. The coefficient of friction increases linearly as the solute to iron atomic radius ratio increases or decreases from unity. The chemical activity of the alloying elements was also an important parameter in controlling adhesion and friction of alloys, as these latter properties are highly dependent upon the d bond character of the elements.
System for controlling child safety seat environment
NASA Technical Reports Server (NTRS)
Elrod, Susan V. (Inventor); Dabney, Richard W. (Inventor)
2008-01-01
A system is provided to control the environment experienced by a child in a child safety seat. Each of a plurality of thermoelectric elements is individually controllable to be one of heated and cooled relative to an ambient temperature. A first portion of the thermoelectric elements are positioned on the child safety seat such that a child sitting therein is positioned thereover. A ventilator coupled to the child safety seat moves air past a second portion of the thermoelectric elements and filters the air moved therepast. One or more jets coupled to the ventilator receive the filtered air. Each jet is coupled to the child safety seat and can be positioned to direct the heated/cooled filtered air to the vicinity of the head of the child sitting in the child safety seat.
Compact fluorescent light (CFL) bulbs contain a few milligrams (mg) of elemental mercury. When a CFL breaks, some of the mercury is immediately released as elemental mercury vapor and the remainder is deposited on indoor surfaces with the bulb debris. In a controlled study design...
Seven Elements Important to Successful Implementation of Early Literacy Intervention
ERIC Educational Resources Information Center
Foorman, Barbara; Dombek, Jennifer; Smith, Kevin
2016-01-01
The objective of this article is to describe seven elements important to successful implementation of early literacy intervention. The seven elements are drawn from research as well as from the authors' recent randomized controlled trial of effective early literacy interventions in kindergarten through second grade in 55 schools across Florida.…
Series resonance inverter with triggered vacuum gaps
NASA Astrophysics Data System (ADS)
Damstra, Geert C.; Zhang, X.
1994-05-01
Series resonance inverters based on semi-conductor switching elements are well-known and have a wide range of application, mainly for lower voltages. For high voltage application many switching elements have to be put in series to obtain sufficient blocking voltage. Voltage grinding and multiple gate control elements are needed. There is much experience with the triggered vacuum gaps as high voltage/high current single shot elements, for example in reignition circuits for synthetic circuit breaker tests. These elements have a blocking voltage of 50 - 100 kV and are triggerable by a light fiber control device. A prototype inverter has been developed that generates 0.1 Hz, 30 kV AC voltages with a flat top for tests on cables and capacitors of many micro farads fed from a low voltage supply of about 600 V. Only two TVG elements are needed to switch the resonant circuit alternatively on the positive or negative supply. The resonant circuit itself consists of the capacitance of the testobject and a high quality inductor that determines the frequency and the peak current of the voltage reversing process.
Concurrent design of an RTP chamber and advanced control system
DOE Office of Scientific and Technical Information (OSTI.GOV)
Spence, P.; Schaper, C.; Kermani, A.
1995-12-31
A concurrent-engineering approach is applied to the development of an axisymmetric rapid-thermal-processing (RTP) reactor and its associated temperature controller. Using a detailed finite-element thermal model as a surrogate for actual hardware, the authors have developed and tested a multi-input multi-output (MIMO) controller. Closed-loop simulations are performed by linking the control algorithm with the finite-element code. Simulations show that good temperature uniformity is maintained on the wafer during both steady and transient conditions. A numerical study shows the effect of ramp rate, feedback gain, sensor placement, and wafer-emissivity patterns on system performance.
Zhang, Linlin; Lv, Jungang; Liao, Chunyang
2012-06-01
Xuanwei and Fuyuan, located in the Yunnan province in southwest of China, are known to have a strikingly high incidence of lung cancer. Among the many factors that have been explored, the association between lung cancer and trace elements has not received enough attention. In this study, dietary samples were collected from 60 families of the lung cancer and control groups and abundances of 14 trace elements were determined using inductively coupled-plasma mass spectroscopy. Accuracy and sensitivity of the method were demonstrated by analyzing national standard reference materials. The results showed that the dietary intake of the trace elements contributed 96.6% of total intake. Among the 14 elements tested, cadmium and titanium were found to be present at a significantly higher level in the food consumed by the cancer group than by the control group. The intake of selenium by the population living in the areas is much lower than what it should be, with the people in the cancer group experiencing even more severe selenium deficiency. In addition, in both groups, the intakes of several essential elements (iron, copper, and zinc) from food and the drinking water were found to be significantly lower than required according to the Chinese Dietary Reference Intakes. The present study of the relationship between trace element intakes of lung cancer cases and controls provides important information urgently needed for the assessment of lung cancer risk of healthy subjects. The study also gives rational dietary suggestions to local residents which is important to the early diagnosis and pretreatment of lung cancer.
FSD- FLEXIBLE SPACECRAFT DYNAMICS
NASA Technical Reports Server (NTRS)
Fedor, J. V.
1994-01-01
The Flexible Spacecraft Dynamics and Control program (FSD) was developed to aid in the simulation of a large class of flexible and rigid spacecraft. FSD is extremely versatile and can be used in attitude dynamics and control analysis as well as in-orbit support of deployment and control of spacecraft. FSD has been used to analyze the in-orbit attitude performance and antenna deployment of the RAE and IMP class satellites, and the HAWKEYE, SCATHA, EXOS-B, and Dynamics Explorer flight programs. FSD is applicable to inertially-oriented spinning, earth oriented, or gravity gradient stabilized spacecraft. The spacecraft flexibility is treated in a continuous manner (instead of finite element) by employing a series of shape functions for the flexible elements. Torsion, bending, and three flexible modes can be simulated for every flexible element. FSD can handle up to ten tubular elements in an arbitrary orientation. FSD is appropriate for studies involving the active control of pointed instruments, with options for digital PID (proportional, integral, derivative) error feedback controllers and control actuators such as thrusters and momentum wheels. The input to FSD is in four parts: 1) Orbit Construction FSD calculates a Keplerian orbit with environmental effects such as drag, magnetic torque, solar pressure, thermal effects, and thruster adjustments; or the user can supply a GTDS format orbit tape for a particular satellite/time-span; 2) Control words - for options such as gravity gradient effects, control torques, and integration ranges; 3) Mathematical descriptions of spacecraft, appendages, and control systems- including element geometry, properties, attitudes, libration damping, tip mass inertia, thermal expansion, magnetic tracking, and gimbal simulation options; and 4) Desired state variables to output, i.e., geometries, bending moments, fast Fourier transform plots, gimbal rotation, filter vectors, etc. All FSD input is of free format, namelist construction. FSD is written in FORTRAN 77, PASCAL, and MACRO assembler for batch execution and has been implemented on a DEC VAX series computer operating under VMS. The PASCAL and MACRO routines (in addition to the FORTRAN program) are supplied as both source and object code, so the PASCAL compiler is not required for implementation. This program was last updated in 1985.
Repetitive element transcripts are elevated in the brain of C9orf72 ALS/FTLD patients.
Prudencio, Mercedes; Gonzales, Patrick K; Cook, Casey N; Gendron, Tania F; Daughrity, Lillian M; Song, Yuping; Ebbert, Mark T W; van Blitterswijk, Marka; Zhang, Yong-Jie; Jansen-West, Karen; Baker, Matthew C; DeTure, Michael; Rademakers, Rosa; Boylan, Kevin B; Dickson, Dennis W; Petrucelli, Leonard; Link, Christopher D
2017-09-01
Significant transcriptome alterations are detected in the brain of patients with amyotrophic lateral sclerosis (ALS), including carriers of the C9orf72 repeat expansion and C9orf72-negative sporadic cases. Recently, the expression of repetitive element transcripts has been associated with toxicity and, while increased repetitive element expression has been observed in several neurodegenerative diseases, little is known about their contribution to ALS. To assess whether aberrant expression of repetitive element sequences are observed in ALS, we analysed RNA sequencing data from C9orf72-positive and sporadic ALS cases, as well as healthy controls. Transcripts from multiple classes and subclasses of repetitive elements (LINEs, endogenous retroviruses, DNA transposons, simple repeats, etc.) were significantly increased in the frontal cortex of C9orf72 ALS patients. A large collection of patient samples, representing both C9orf72 positive and negative ALS, ALS/FTLD, and FTLD cases, was used to validate the levels of several repetitive element transcripts. These analyses confirmed that repetitive element expression was significantly increased in C9orf72-positive compared to C9orf72-negative or control cases. While previous studies suggest an important link between TDP-43 and repetitive element biology, our data indicate that TDP-43 pathology alone is insufficient to account for the observed changes in repetitive elements in ALS/FTLD. Instead, we found that repetitive element expression positively correlated with RNA polymerase II activity in postmortem brain, and pharmacologic modulation of RNA polymerase II activity altered repetitive element expression in vitro. We conclude that increased RNA polymerase II activity in ALS/FTLD may lead to increased repetitive element transcript expression, a novel pathological feature of ALS/FTLD. © The Author 2017. Published by Oxford University Press.
NASA Technical Reports Server (NTRS)
Dietrich, F. J.; Koloboff, G. J.; Martel, R. J.; Johnson, C. C. (Inventor)
1974-01-01
A spin stabilized satellite has an electronically despun antenna array comprising a multiplicity of peripheral antenna elements. A high gain energy beam is established by connecting a suitable fraction or array of the elements in phase. The beam is steered or caused to scan by switching elements in sequence into one end of the array as elements at the other end of the array are switched out. The switching transients normally associated with such steering are avoided by an amplitude control system. Instead of abruptly switching from one element to the next, a fixed value of power is gradually transferred from the element at the trailing edge of the array to the element next to the leading edge.
Iwamoto, Masami; Nakahira, Yuko; Kimpara, Hideyuki; Sugiyama, Takahiko; Min, Kyuengbo
2012-10-01
A few reports suggest differences in injury outcomes between cadaver tests and real-world accidents under almost similar conditions. This study hypothesized that muscle activity could primarily cause the differences, and then developed a human body finite element (FE) model with individual muscles. Each muscle was modeled as a hybrid model of bar elements with active properties and solid elements with passive properties. The model without muscle activation was firstly validated against five series of cadaver test data on impact responses in the anterior-posterior direction. The model with muscle activation levels estimated based on electromyography (EMG) data was secondly validated against four series of volunteer test data on bracing effects for stiffness and thickness of an upper arm muscle, and braced driver's responses under a static environment and a brake deceleration. A muscle controller using reinforcement learning (RL), which is a mathematical model of learning process in the basal ganglia associated with human postural controls, were newly proposed to estimate muscle activity in various occupant conditions including inattentive and attentive conditions. Control of individual muscles predicted by RL reproduced more human like head-neck motions than conventional control of two groups of agonist and antagonist muscles. The model and the controller demonstrated that head-neck motions of an occupant under an impact deceleration of frontal crash were different in between a bracing condition with maximal braking force and an occupant condition predicted by RL. The model and the controller have the potential to investigate muscular effects in various occupant conditions during frontal crashes.
Low Intensity Conflict as Practiced by John Singleton Mosby in the American Civil War
1986-06-06
perserverence, and (12) his leadership style was personalized, charismatic, and nonbureaucratic Mosby acquired his leadership abilities in a number of...operation; equipment and logistics; communications, command and control; results; the element of chance; and leadership . In addition, Mosbys background...logistics; communications, command and control; results; the element of chance; and leadership . In addition, Mosby’s background and character are also
ERIC Educational Resources Information Center
Kroeze, Willemieke; Oenema, Anke; Dagnelie, Pieter C.; Brug, Johannes
2008-01-01
This study investigated the minimally required feedback elements of a computer-tailored dietary fat reduction intervention to be effective in improving fat intake. In all 588 Healthy Dutch adults were randomly allocated to one of four conditions in an randomized controlled trial: (i) feedback on dietary fat intake [personal feedback (P feedback)],…
PROCESS FOR MAKING NEUTRON-ABSORBING BODIES
Schippereit, G.H.; Lang, R.M.
1961-11-14
A process for making a control element for a nuclear reactor and the control element prepared by the process are described. Equally spaced, conically shaped depressions are formed in one face of a metal plate, spheres of boron of uniform size are placed in the depressions, another plate is welded on top of this place covering the depressions, and the joined plates are rolled to the desired thickness. (AEC)
NASA Technical Reports Server (NTRS)
Bair, Clayton H.; Brockman, Philip; Hess, Robert V.; Modlin, Edward A.
1988-01-01
Theoretical and experimental frequency narrowing studies of a Ti:sapphire ring laser with no intracavity optical elements are reported. Frequency narrowing has been achieved using a birefringent filter between a partially reflecting reverse wave suppressor mirror and the ring cavity output mirror. Results of CW diode laser injection seeding are reported.
Regulation of expression of transgenes in developing fish.
Moav, B; Liu, Z; Caldovic, L D; Gross, M L; Faras, A J; Hackett, P B
1993-05-01
The transcriptional regulatory elements of the beta-actin gene of carp (Cyprinus carpio) have been examined in zebrafish and goldfish harbouring transgenes. The high sequence conservation of the putative regulatory elements in the beta-actin genes of animals suggested that their function would be conserved, so that transgenic constructs with the same transcriptional control elements would promote similar levels of transgene expression in different species of transgenic animals. To test this assumption, we analysed the temporal expression of a reporter gene under the control of transcriptional control sequences from the carp beta-actin gene in zebrafish (Brachydanio rerio) and goldfish (Carrasius auratus). Our results indicated that, contrary to expectations, combinations of different transcriptional control elements affected the level, duration, and onset of gene expression differently in developing zebrafish and goldfish. The major differences in expression of beta-actin/CAT (chloramphenicol acetyltransferase) constructs in zebrafish and goldfish were: (1) overall expression was almost 100-fold higher in goldfish than in zebrafish embryos, (2) the first intron had an enhancing effect on gene expression in zebrafish but not in goldfish, and (3) the serum-responsive/CArG-containing regulatory element in the proximal promoter was not always required for maximal CAT activity in goldfish, but was required in zebrafish. These results suggest that in the zebrafish, but not in the goldfish, there may be interactions between motifs in the proximal promoter and the first intron which appear to be required for maximal enhancement of transcription.
Yang, Rongwang; Zhang, Yanyi; Gao, Weijia; Lin, Nannan; Li, Rong; Zhao, Zhengyan
2018-06-16
Some trace elements may participate in the pathogenesis of attention-deficit hyperactivity disorder (ADHD). This study aimed to investigate the trace element status of zinc (Zn), copper (Cu), iron (Fe), magnesium (Mg), and lead (Pb) in children with ADHD, and to compare them with normal controls. Associations between examined elements and SNAP-IV rating scores of ADHD symptoms were also assessed. Four hundred nineteen children with ADHD (8.8 ± 2.1 years) and 395 matched normal controls (8.9 ± 1.7 years) were recruited in the study. The concentrations of Zn, Fe, Cu, Mg, and Pb in the whole blood were measured by atomic absorption spectrometry. Lower zinc levels (P < 0.001) and the number out of normal ranges (P = 0.015) were found in children with ADHD when compared with the normal control group. The difference remained when adjusting the factor of BMI z-score. No significant between-group differences were found in levels of other elements. Zinc levels were negatively correlated with parent-rated scores of inattentive subscale of SNAP-IV (r = - 0.40) as well as with total score of SNAP-IV (r = - 0.24). Other significant associations were not observed. The present results indicated that there were alterations in blood levels of zinc, which was associated with the symptom scores of ADHD.
National Mapping of Wetland Connectivity
Connectivity has become a major focus of hydrological and ecological studies. Connectivity influences fluxes between landscape elements, while isolation reduces flows between elements. Thus connectivity can be an important characteristic controlling ecosystem services. Hydrolo...
Active shape control of composite blades using shape memory actuation
NASA Astrophysics Data System (ADS)
Chandra, Ramesh
2001-10-01
This paper presents active shape control of composite beams using shape memory actuation. Shape memory alloy (SMA) bender elements trained to memorize bending shape were used to induce bending and twisting deformations in composite beams. Bending-torsion coupled graphite-epoxy and kevlar-epoxy composite beams with Teflon inserts were manufactured using an autoclave-molding technique. Teflon inserts were replaced by trained SMA bender elements. Composite beams with SMA bender elements were activated by heating these using electrical resistive heating and the bending and twisting deformations of the beams were measured using a mirror and laser system. The structural response of the composite beams activated by SMA elements was predicted using the Vlasov theory, where these beams were modeled as open sections with many branches. The bending moment induced by a SMA bender element was calculated from its experimentally determined memorized shape. The bending, torsion, and bending-torsion coupling stiffness coefficients of these beams were obtained using analytical formulation of an open-section composite beam with many branches (Vlasov theory).
NASA Astrophysics Data System (ADS)
Ordou, N.; Agranovski, I. E.
2017-12-01
Air contamination resulting from bushfires is becoming increasingly important research question, as such disasters frequently occur in many countries. The objectives of this project were focused on physical and chemical characterisations of particulate emission resulting from burning of common representatives of Australian vegetation under controlled laboratory conditions. It was found that leaves are burned mostly with flaming phase and producing black smoke resulting in larger particles compared to white smoke in case of branches and grass, dominated by smouldering phase, producing finer particles. Following elemental analysis determined nine main elements in three different size fractions of particulate matter for each category of burning material, ranging from 14.1 μm to particle sizes below 2.54 μm. Potassium was found to be one of the main biomass markers, and sulphur was the ubiquitous element among the smoke particles followed by less prevalent trace elements like Na, Al, Mg, Zn, Si, Ca, and Fe.
De Boer, Jan L M; Ritsema, Rob; Piso, Sjoerd; Van Staden, Hans; Van Den Beld, Wilbert
2004-07-01
Two screening methods were developed for rapid analysis of a great number of urine and blood samples within the framework of an exposure check of the population after a firework explosion. A total of 56 elements was measured including major elements. Sample preparation consisted of simple dilution. Extensive quality controls were applied including element addition and the use of certified reference materials. Relevant results at levels similar to those found in the literature were obtained for Co, Ni, Cu, Zn, Sr, Cd, Sn, Sb, Ba, Tl, and Pb in urine and for the same elements except Ni, Sn, Sb, and Ba in blood. However, quadrupole ICP-MS has limitations, mainly related to spectral interferences, for the analysis of urine and blood, and these cause higher detection limits. The general aspects discussed in the paper give it wider applicability than just for analysis of blood and urine-it can for example be used in environmental analysis.
Godson, Prince S; Magesh, N S; Peter, T Simon; Chandrasekar, N; Krishnakumar, S; Vincent, Salom Gnana Thanga
2018-01-01
Forty two surface sediment samples were collected in order to document baseline elemental concentration along the Southwest coast of Tamil Nadu, India. The elements detected were Manganese (Mn), Zinc (Zn), Iron (Fe), Copper (Cu), Nickel (Ni) and Lead (Pb). The concentration of Fe and Mn was primarily controlled by the riverine input. The source of Pb and Zn is attributed to leaded petrol and anti-biofouling paints. The calculated index (EF, Igeo and CF) suggests that the sediments of the study area are significantly enriched with all elements except Pb. The contamination factor showed the order of Mn>Zn>Fe>Cu>Ni>Pb. The sediment pollution index (SPI) revealed that the sediments belonged to low polluted to dangerous category. The correlation matrix and dendrogram showed that the elemental distribution was chiefly controlled by riverine input as well as anthropogenic activity in the coast. Copyright © 2017 Elsevier Ltd. All rights reserved.
Tabatadze, T; Zhorzholiani, L; Kherkheulidze, M; Kandelaki, E; Ivanashvili, T
2015-11-01
Our study aims evaluation of level of essential trace elements and heavy metals in the hair samples of children with autistic spectrum disorder (ASD) and identification of changes that are associated with autistic spectrum disorders. Case-control study was conducted at Child Development Center of Iashvili Children's Central Hospital (LD).We studied 60 children aged from 4 to 5 years old. The concentrations of 28 elements among (Ca,Zn, K, Fe, Cu, Se, Mn, Cr, S, Br, Cl, Co, Ag, V, Ni, Rb, Mo, Sr, Ti, Ba, Pb, As, Hg, Cd, Sb, Zr, Sn, Bi) them trace elements and toxic metals) were determined in scalp hair samples of children (n=30) with autistic spectrum disorder (ASD) and from control group of healthy children (n=30) with matched sex and age. Micro-elemental status was detected in the hair, with roentgen-fluorescence spectrometer method (Method MBИ 081/12-4502-000, Apparatus ALVAX- CIP, USA - UKRAIN) .To achieve the similarity of study and control groups, pre and postnatal as well as family and social history were assessed and similar groups were selected. Children with genetic problems, malnourished children, children from families with social problems were excluded from the study. The diagnosis of ASD were performed by pediatrician and psychologist (using M-CHAT and ADOS) according to DSM IV (Diagnostic and Statistical Manual of Mental Disorders from the American Psychiatric association) criteria. The study was statistically analyzed using computer program SPSS 19. Deficiencies of essential trace microelements revealed in both group, but there was significant difference between control and studied groups. The most deficient element was zinc (92% in target and 20% in control), then - manganese (55% and 8%) and selenium (38% and 4%). In case of cooper study revealed excess concentration of this element only in target group in 50% of cases. The contaminations to heavy metals were detected in case of lead (78% and 16), mercury (43% and 10%) and cadmium (38% and 8%). The study statistical results indicated, that deficient concentrations of trace elements such as zinc, manganese, molybdenum and selenium in hair significantly linked with ASD (Kramer's V was 0,740; 0,537; 0,333; 0,417 accordingly). In case of cooper we got excess levels of this element and this data was highly linked with autism spectrum disorder. We got high associations and significant values between of lead, mercury and cadmium concentrations and ASD. Study results indicate that there are significant differences of hair essential trace elements concentrations in children with autism spectrum disorder comparing with healthy children group. The result obtained also showed high contamination to heavy metals such as lead, mercury and cadmium in ASD children compared to healthy ones. So, our study demonstrated alteration in levels of toxic heavy metals and essential trace elements in children with autistic spectrum disorders as compared to healthy children. This suggests a possible pathophysiological role of heavy metals and trace elements in the genesis of symptoms of autism spectrum disorders.
The Effect of Volumetric Porosity on Roughness Element Drag
NASA Astrophysics Data System (ADS)
Gillies, John; Nickling, William; Nikolich, George; Etyemezian, Vicken
2016-04-01
Much attention has been given to understanding how the porosity of two dimensional structures affects the drag force exerted by boundary-layer flow on these flow obstructions. Porous structures such as wind breaks and fences are typically used to control the sedimentation of sand and snow particles or create micro-habitats in their lee. Vegetation in drylands also exerts control on sediment transport by wind due to aerodynamic effects and interaction with particles in transport. Recent research has also demonstrated that large spatial arrays of solid three dimensional roughness elements can be used to reduce sand transport to specified targets for control of wind erosion through the effect of drag partitioning and interaction of the moving sand with the large (>0.3 m high) roughness elements, but porous elements may improve the effectiveness of this approach. A thorough understanding of the role porosity plays in affecting the drag force on three-dimensional forms is lacking. To provide basic understanding of the relationship between the porosity of roughness elements and the force of drag exerted on them by fluid flow, we undertook a wind tunnel study that systematically altered the porosity of roughness elements of defined geometry (cubes, rectangular cylinders, and round cylinders) and measured the associated change in the drag force on the elements under similar Reynolds number conditions. The elements tested were of four basic forms: 1) same sized cubes with tubes of known diameter milled through them creating three volumetric porosity values and increasing connectivity between the tubes, 2) cubes and rectangular cylinders constructed of brass screen that nested within each other, and 3) round cylinders constructed of brass screen that nested within each other. The two-dimensional porosity, defined as the ratio of total surface area of the empty space to the solid surface area of the side of the element presented to the fluid flow was conserved at 0.519 for the cubes and 0.525 for the mesh forms. Results from the study indicate that as volumetric porosity increases, the force of drag on an element increases although the 2-dimensional porosity remains unchanged for the case of the cube forms. The mesh forms show a similar result that with increasing number of internal forms present, drag increases, but the drag curves are different, suggesting the kind of porosity has an effect on drag. An important scaling parameter that controls drag on the cubes is the permeability (K) of the element, which is a function of the diameter of the tubes and the porosity. K seems to be of lesser importance for controlling drag on the mesh forms. We hypothesize that the drag force data do not universally collapse as a function of permeability due to Reynolds number dependency on flow conditions within the elements that can be laminar, transitional, or turbulent even though flow exterior to the forms is fully turbulent. For the mesh forms, the greatest effect on drag occurs with the addition of the first internal form with subsequent additions showing very little additional effect.
Reliability modelling and analysis of a multi-state element based on a dynamic Bayesian network
Xu, Tingxue; Gu, Junyuan; Dong, Qi; Fu, Linyu
2018-01-01
This paper presents a quantitative reliability modelling and analysis method for multi-state elements based on a combination of the Markov process and a dynamic Bayesian network (DBN), taking perfect repair, imperfect repair and condition-based maintenance (CBM) into consideration. The Markov models of elements without repair and under CBM are established, and an absorbing set is introduced to determine the reliability of the repairable element. According to the state-transition relations between the states determined by the Markov process, a DBN model is built. In addition, its parameters for series and parallel systems, namely, conditional probability tables, can be calculated by referring to the conditional degradation probabilities. Finally, the power of a control unit in a failure model is used as an example. A dynamic fault tree (DFT) is translated into a Bayesian network model, and subsequently extended to a DBN. The results show the state probabilities of an element and the system without repair, with perfect and imperfect repair, and under CBM, with an absorbing set plotted by differential equations and verified. Through referring forward, the reliability value of the control unit is determined in different kinds of modes. Finally, weak nodes are noted in the control unit. PMID:29765629
Williamson, M.M.; Pratt, G.A.
1999-06-08
The invention provides an elastic actuator consisting of a motor and a motor drive transmission connected at an output of the motor. An elastic element is connected in series with the motor drive transmission, and this elastic element is positioned to alone support the full weight of any load connected at an output of the actuator. A single force transducer is positioned at a point between a mount for the motor and an output of the actuator. This force transducer generates a force signal, based on deflection of the elastic element, that indicates force applied by the elastic element to an output of the actuator. An active feedback force control loop is connected between the force transducer and the motor for controlling the motor. This motor control is based on the force signal to deflect the elastic element an amount that produces a desired actuator output force. The produced output force is substantially independent of load motion. The invention also provides a torsional spring consisting of a flexible structure having at least three flat sections each connected integrally with and extending radially from a central section. Each flat section extends axially along the central section from a distal end of the central section to a proximal end of the central section. 30 figs.
Aguilar, Marcelo; Mondaca, Pedro; Ginocchio, Rosanna; Vidal, Kooichi; Sauvé, Sébastien; Neaman, Alexander
2018-05-03
Human exposure to trace elements has been a large concern due to the potential health issues. Accordingly, this study aimed to compare the concentrations of arsenic, copper, and zinc in the edible parts of vegetables grown in a mining-agricultural area and in an exclusively agricultural area and to compare the potential human health risks of consuming vegetables from both areas. The consumption habits of the studied population were extracted from the 2010 National Alimentary Survey of Chile. In most cases, the concentrations of trace elements in the edible tissues of vegetables (lettuce, spinach, garlic, onion, carrot, potato, sweet corn, and tomato) were higher in the mining-agricultural area than those in the control area. This difference was most pronounced for leafy vegetables, with arsenic being the trace element of concern. Specifically, the arsenic concentrations in the edible tissues of lettuce and spinach were 8.2- and 5.4-fold higher, respectively, in the mining-agricultural area than in the control area. Lettuce was the vegetable of concern due to its relatively high consumption and relatively high concentration of trace elements. Nevertheless, there was no health risk associated with vegetable consumption in either the mining area or the control area because none of the HQ values surpassed 1.0.
Ellingson, William A.; Forster, George A.
1999-11-02
Apparatus and a method for controlling the flow rate of viscous materials through a nozzle includes an apertured main body and an apertured end cap coupled together and having an elongated, linear flow channel extending the length thereof. An end of the main body is disposed within the end cap and includes a plurality of elongated slots concentrically disposed about and aligned with the flow channel. A generally flat cam plate having a center aperture is disposed between the main body and end cap and is rotatable about the flow channel. A plurality of flow control vane assemblies are concentrically disposed about the flow channel and are coupled to the cam plate. Each vane assembly includes a vane element disposed adjacent the end of the flow channel. Rotation of the cam plate in a first direction causes a corresponding rotation of each of the vane elements for positioning the individual vane elements over the aperture in the end cap blocking flow through the flow channel, while rotation in an opposite direction removes the vane elements from the aperture and positions them about the flow channel in a nested configuration in the full open position, with a continuous range of vane element positions available between the full open and closed positions.
Jin, Erqing; Wong, Lynn; Jiao, Yun; Engel, Jake; Holdridge, Benjamin; Xu, Peng
2017-12-01
Engineering cell factories for producing biofuels and pharmaceuticals has spurred great interests to develop rapid and efficient synthetic biology tools customized for modular pathway engineering. Along the way, combinatorial gene expression control through modification of regulatory element offered tremendous opportunity for fine-tuning gene expression and generating digital-like genetic circuits. In this report, we present an efficient evolutionary approach to build a range of regulatory control elements. The reported method allows for rapid construction of promoter, 5'UTR, terminator and trans -activating RNA libraries. Synthetic overlapping oligos with high portion of degenerate nucleotides flanking the regulatory element could be efficiently assembled to a vector expressing fluorescence reporter. This approach combines high mutation rate of the synthetic DNA with the high assembly efficiency of Gibson Mix. Our constructed library demonstrates broad range of transcriptional or translational gene expression dynamics. Specifically, both the promoter library and 5'UTR library exhibits gene expression dynamics spanning across three order of magnitude. The terminator library and trans -activating RNA library displays relatively narrowed gene expression pattern. The reported study provides a versatile toolbox for rapidly constructing a large family of prokaryotic regulatory elements. These libraries also facilitate the implementation of combinatorial pathway engineering principles and the engineering of more efficient microbial cell factory for various biomanufacturing applications.
Effect of lipid peroxidation, antioxidants, macro minerals and trace elements on eczema.
Amin, Mohammad Nurul; Liza, Kaniz Fatema; Sarwar, Md Shahid; Ahmed, Jamiuddin; Adnan, Md Tareek; Chowdhury, Manjurul Islam; Hossain, Mohammad Zahid; Islam, Mohammad Safiqul
2015-09-01
The exact etiology and pathogenesis of eczema are not yet fully understood, although different factors are considered as pathogenic mechanisms in the development of eczema. Our study was designed to determine extent of serum lipid peroxidation, antioxidants, macro minerals and trace elements in patients with eczema, and thereby, find any pathophysiological correlation. The study was conducted as a case-control study with 65 eczema patients as cases and 65 normal healthy individuals as controls. Lipid peroxidation was assessed by measuring the serum level of malondialdehyde (MDA). Antioxidants- vitamin A and E concentration was determined by RP-HPLC method whereas vitamin C was evaluated for serum ascorbic acid by UV spectrophotometric method. Serum macro minerals (Na, K, Ca) and trace elements (Zn, Fe) were determined by Atomic Absorption Spectroscopy (AAS). This study found significantly higher level of MDA (p < 0.001) and lower level of antioxidants (p < 0.05) in patients in comparison to the control subjects. Analysis of serum macro minerals (Na, K and Ca) and trace elements (Zn, Fe) found that the mean values of Na, K, Ca, Zn and Fe were 2771.60 ± 75.64, 66.33 ± 3.03, 48.41 ± 2.50, 0.30 ± 0.02 and 0.29 ± 0.009 mg/L for the patient group and 3284.81 ± 34.51, 162.18 ± 3.72, 87.66 ± 2.10, 0.75 ± 0.06 and 0.87 ± 0.06 mg/L for the control group, accordingly. There was a significant difference for all the minerals between the patients and controls (p < 0.001). This study suggests a strong association between the pathogenesis of eczema with the elevated level of MDA and depleted level of antioxidants, macro minerals, and trace elements.
NASA Technical Reports Server (NTRS)
Meyer, Jay L. (Inventor); Messick, Glenn C. (Inventor); Nardell, Carl A. (Inventor); Hendlin, Martin J. (Inventor)
2011-01-01
A spherical mounting assembly for mounting an optical element allows for rotational motion of an optical surface of the optical element only. In that regard, an optical surface of the optical element does not translate in any of the three perpendicular translational axes. More importantly, the assembly provides adjustment that may be independently controlled for each of the three mutually perpendicular rotational axes.
Cycling firing method for bypass operation of bridge converters
Zabar, Zivan
1982-01-01
The bridge converter comprises a number of switching elements and an electronic logic system which regulated the electric power levels by controlling the firing, i.e., the initiation of the conduction period of the switching elements. Cyclic firing of said elements allows the direct current to bypass the alternating current system with high power factor and negligible losses.
A miniature fuel reformer system for portable power sources
NASA Astrophysics Data System (ADS)
Dolanc, Gregor; Belavič, Darko; Hrovat, Marko; Hočevar, Stanko; Pohar, Andrej; Petrovčič, Janko; Musizza, Bojan
2014-12-01
A miniature methanol reformer system has been designed and built to technology readiness level exceeding a laboratory prototype. It is intended to feed fuel cells with electric power up to 100 W and contains a complete setup of the technological elements: catalytic reforming and PROX reactors, a combustor, evaporators, actuation and sensing elements, and a control unit. The system is engineered not only for performance and quality of the reformate, but also for its lightweight and compact design, seamless integration of elements, low internal electric consumption, and safety. In the paper, the design of the system is presented by focussing on its miniaturisation, integration, and process control.
Whittemore, Stephen Richard
2013-09-10
Imaging systems include a detector and a spatial light modulator (SLM) that is coupled so as to control image intensity at the detector based on predetermined detector limits. By iteratively adjusting SLM element values, image intensity at one or all detector elements or portions of an imaging detector can be controlled to be within limits. The SLM can be secured to the detector at a spacing such that the SLM is effectively at an image focal plane. In some applications, the SLM can be adjusted to impart visible or hidden watermarks to images or to reduce image intensity at one or a selected set of detector elements so as to reduce detector blooming
Modeling and Control of the Redundant Parallel Adjustment Mechanism on a Deployable Antenna Panel
Tian, Lili; Bao, Hong; Wang, Meng; Duan, Xuechao
2016-01-01
With the aim of developing multiple input and multiple output (MIMO) coupling systems with a redundant parallel adjustment mechanism on the deployable antenna panel, a structural control integrated design methodology is proposed in this paper. Firstly, the modal information from the finite element model of the structure of the antenna panel is extracted, and then the mathematical model is established with the Hamilton principle; Secondly, the discrete Linear Quadratic Regulator (LQR) controller is added to the model in order to control the actuators and adjust the shape of the panel. Finally, the engineering practicality of the modeling and control method based on finite element analysis simulation is verified. PMID:27706076
Long life reliability thermal control systems study
NASA Technical Reports Server (NTRS)
Scollon, T. R., Jr.; Killen, R. E.
1972-01-01
The results of a program undertaken to conceptually design and evaluate a passive, high reliability, long life thermal control system for space station application are presented. The program consisted of four steps: (1) investigate and select potential thermal system elements; (2) conceive, evaluate and select a thermal control system using these elements; (3) conduct a verification test of a prototype segment of the selected system; and (4) evaluate the utilization of waste heat from the power supply. The result of this project is a conceptual thermal control system design which employs heat pipes as primary components, both for heat transport and temperature control. The system, its evaluation, and the test results are described.
Implementation of a self-controlling heater
NASA Technical Reports Server (NTRS)
Strange, M. G.
1973-01-01
Temperature control of radiation sensors, targets, and other critical components is a common requirement in modern scientific instruments. Conventional control systems use a heater and a temperature sensor mounted on the body to be controlled. For proportional control, the sensor provides feedback to circuitry which drives the heater with an amount of power proportional to the temperature error. It is impractical or undesirable to mount both a heater and a sensor on certain components such as ultra-small parts or thin filaments. In principle, a variable current through the element is used for heating, and the change in voltage drop due to the element's temperature coefficient is separated and used to monitor or control its own temperature. Since there are no thermal propagation delays between heater and sensor, such control systems are exceptionally stable.
Recycling of trace elements required for humans in CELSS.
Ashida, A
1994-11-01
Recycle of complete nourishment necessary for human should be constructed in CELSS (Controlled Ecological Life Support Systems). Essential elements necessary for human support are categorized as major elements, semi-major elements and trace elements. Recently, trace elements have been identified from considerations of local diseases, food additive problems, pollution problems and adult diseases, consisting of Fe, Zn, Cu, Se, Co, F, Si, Mn, Cr, I, As, Mo, Ni, V, Sn, Li, Br, Cd, Pb, B. A review of the biogeochemical history of the earth's biosphere and the physiological nature of humans and plants explains some of the requirements. A possible route for intake of trace elements is considered that trace elements are dissolved in some chemical form in water, absorbed by plants through their roots and then transfered to human as foods. There may be a possibility that living things absorb some trace elements from atmosphere. Management and recycling of trace elements in CELSS is discussed.
Recycling of trace elements required for humans in CELSS
NASA Astrophysics Data System (ADS)
Ashida, A.
1994-11-01
Recycle of complete nourishment necessary for human should be constructed in CELSS (Controlled Ecological Life Support Systems). Essential elements necessary for human support are categorized as major elements, semi-major elements and trace elements. Recently, trace elements have been identified from considerations of local diseases, food additive problems, pollution problems and adult diseases, consisting of Fe, Zn, Cu, Se, Co, F, Si, Mn, Cr, I, As, Mo, Ni, V, Sn, Li, Br, Cd, Pb, B. A review of the biogeochemical history of the earth's biosphere and the physiological nature of humans and plants explains some of the requirements. A possible route for intake of trace elements is considered that trace elements are dissolved in some chemical form in water, absorbed by plants through their roots and then transfered to human as foods. There may be a posibility that living things absorb some trace elements from atmosphere. Management and recycling of trace elements in CELSS is discussed.
Elements of an Asbestos Operations and Maintenance (O&M) Program
Links to descriptions of Elements of an Operations and Maintenance (O&M) Program: Training, Occupant Notification, Monitoring ACM, Job-Site Controls for Work Involving ACM, Safe Work Practices, Recordkeeping, Worker Protection.
Position control system for use with micromechanical actuators
Guckel, Henry; Stiers, Eric W.
2000-01-01
A positioning system adapted for use with micromechanical actuators provides feedback control of the position of the movable element of the actuator utilizing a low Q sensing coil. The effective inductance of the sensing coil changes with position of the movable element to change the frequency of oscillation of a variable oscillator. The output of the variable oscillator is compared in a phase detector to a reference oscillator signal. The phase detector provides a pulsed output having a pulse duty cycle related to the phase or frequency difference between the oscillator signals. The output of the phase detector is provided to a drive coil which applies a magnetic force to the movable element which balances the force of a spring. The movable element can be displaced to a new position by changing the frequency of the reference oscillator.
MCNP-model for the OAEP Thai Research Reactor
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gallmeier, F.X.; Tang, J.S.; Primm, R.T. III
An MCNP input was prepared for the Thai Research Reactor, making extensive use of the MCNP geometry`s lattice feature that allows a flexible and easy rearrangement of the core components and the adjustment of the control elements. The geometry was checked for overdefined or undefined zones by two-dimensional plots of cuts through the core configuration with the MCNP geometry plotting capabilities, and by a three-dimensional view of the core configuration with the SABRINA code. Cross sections were defined for a hypothetical core of 67 standard fuel elements and 38 low-enriched uranium fuel elements--all filled with fresh fuel. Three test calculationsmore » were performed with the MCNP4B-code to obtain the multiplication factor for the cases with control elements fully inserted, fully withdrawn, and at a working position.« less
Thermal-Hydraulic Transient Analysis of a Packed Particle Bed Reactor Fuel Element
1990-06-01
long fuel elements, arranged to form a core , were analyzed for an up-power transient from 0 MWt to approximately 18 MWt. The simple model significantly...VARIATIONS IN FUEL ELEMENT GEOMETRY ............. 60 4.4 VARIATIONS IN THE MANNER OF TRANSIENT CONTROL ..... 62 4.5 CORE REPRESENTATION BY MULTIPLE FUEL ...the HTGR , however, the PBR packs small fuel particles between inner and outer retention elements, designated as frits. The PBR is appropriate for a
2006-03-01
Owens J. “A Set of Modified Equinoctial Orbit Elements ,” Celestial Mechanics, 36 :409–419 (1985). 35. Wie B. Space Vehicle Dynamics and Control...14 MEE modified equinoctial elements . . . . . . . . . . . . . . . . . . . . . . . 14 TLE two-line element set ...satellite [32]. Vallado’s model will be incorporated into this thesis. 2.3.3 Modified Equinoctial Orbital Elements . For most astrodynamics problems, one of
A curvilinear, anisotropic, p-version, brick finite element based on geometric entities
NASA Technical Reports Server (NTRS)
Hinnant, Howard E.
1992-01-01
A 'brick' solid finite element is presently developed on the basis of the p-version analysis, and used to demonstrate the FEM concept of 'geometric entities'. This method eliminates interelement discontinuities between low- and high-order elements, allowing very fine control over the shape-function order in various parts of the model. Attention is given to the illustrative cases of a one-element model of an elliptic pipe, and a square cross-section cantilevered beam.
Metali, Faizah; Abu Salim, Kamariah; Tennakoon, Kushan; Burslem, David F R P
2015-01-01
Foliar elemental concentrations are predictors of life-history variation and contribute to spatial patterns in biogeochemical cycling. We examined the contributions of habitat association, local soil environment, and elemental interactions to variation in foliar elemental concentrations in tropical trees using methods that account for phylogeny. We sampled top-soils and leaves of 58 tropical trees in heath forest (HF) on nutrient-poor sand and mixed dipterocarp forest (MDF) on nutrient-rich clay soils. A phylogenetic generalized least squares method was used to determine how foliar nutrient and aluminium (Al) concentrations varied in response to habitat distribution, soil chemistry and other elemental concentrations. Foliar nitrogen (N) and Al concentrations were greater for specialists of MDF than for specialists of HF, while foliar calcium (Ca) concentrations showed the opposite trend. Foliar magnesium (Mg) concentrations were lower for generalists than for MDF specialists. Foliar element concentrations were correlated with fine-scale variation in soil chemistry in phylogenetically controlled analyses across species, but there was limited within-species plasticity in foliar elemental concentrations. Among Al accumulators, foliar Al concentration was positively associated with foliar Ca and Mg concentrations, and negatively associated with foliar phosphorus (P) concentrations. The Al-accumulation trait and relationships between foliar elemental and Al concentrations may contribute to species habitat partitioning and ecosystem-level differences in biogeochemical cycles. © 2014 The Authors. New Phytologist © 2014 New Phytologist Trust.
NASA Astrophysics Data System (ADS)
Lu, Xin; Matsubae, Kazuyo; Nakajima, Kenichi; Nakamura, Shinichiro; Nagasaka, Tetsuya
2016-06-01
Cobalt and nickel are high-value commodity metals and are mostly used in the form of highly alloyed materials. The alloying elements used may cause contamination problems during recycling. To ensure maximum resource efficiency, an understanding of the removability of these alloying elements and the controllability of some of the primary alloying elements is essential with respect to the recycling of end-of-life (EoL) nickel- and cobalt-based superalloys by remelting. In this study, the distribution behaviors of approximately 30 elements that are usually present in EoL nickel- and cobalt-based superalloys in the solvent metal (nickel, cobalt, or nickel-cobalt alloy), oxide slag, and gas phases during the remelting were quantitatively evaluated using a thermodynamic approach. The results showed that most of the alloying elements can be removed either in the slag phase or into the gas phase. However, the removal of copper, tin, arsenic, and antimony by remelting is difficult, and they remain as tramp elements during the recycling. On the other hand, the distribution tendencies of iron, molybdenum, and tungsten can be controlled by changing the remelting conditions. To increase the resource efficiency of recycling, preventing contamination by the tramp elements and identifying the alloying compositions of EoL superalloys are significantly essential, which will require the development of efficient prior alloy-sorting systems and advanced separation technologies.
Identification of Regulatory Elements That Control PPARγ Expression in Adipocyte Progenitors
Chou, Wen-Ling; Galmozzi, Andrea; Partida, David; Kwan, Kevin; Yeung, Hui; Su, Andrew I.; Saez, Enrique
2013-01-01
Adipose tissue renewal and obesity-driven expansion of fat cell number are dependent on proliferation and differentiation of adipose progenitors that reside in the vasculature that develops in coordination with adipose depots. The transcriptional events that regulate commitment of progenitors to the adipose lineage are poorly understood. Because expression of the nuclear receptor PPARγ defines the adipose lineage, isolation of elements that control PPARγ expression in adipose precursors may lead to discovery of transcriptional regulators of early adipocyte determination. Here, we describe the identification and validation in transgenic mice of 5 highly conserved non-coding sequences from the PPARγ locus that can drive expression of a reporter gene in a manner that recapitulates the tissue-specific pattern of PPARγ expression. Surprisingly, these 5 elements appear to control PPARγ expression in adipocyte precursors that are associated with the vasculature of adipose depots, but not in mature adipocytes. Characterization of these five PPARγ regulatory sequences may enable isolation of the transcription factors that bind these cis elements and provide insight into the molecular regulation of adipose tissue expansion in normal and pathological states. PMID:24009687
The effects of Chinese five-element music therapy on nursing students with depressed mood.
Chen, Chen-Jung; Sung, Huei-Chuan; Lee, Ming-Shinn; Chang, Ching-Yuan
2015-04-01
This study aimed to evaluate the effects of Chinese five-element music therapy on nursing students with depressed mood. We randomly assigned 71 nursing students from Taiwan with depressed mood to the music and control groups. The music group (n = 31) received Chinese five-element music therapy, whereas the participants in the control group (n = 40) maintained their routine lifestyles with no music therapy. All of the participants were assessed using the Depression Mood Self-Report Inventory for Adolescence, and their salivary cortisol levels were measured. The study found that there was a significant reduction in depression between the pre- and posttherapy test scores and in salivary cortisol levels over time in the music group. After receiving the music therapy, the nursing students' depression levels were significantly reduced (P = 0.038) compared with the control group (P < 0.001). These results indicate that the Chinese five-element music therapy has the potential to reduce the level of depression in nursing students with depressed mood. © 2014 Wiley Publishing Asia Pty Ltd.
Finite element predictions of active buckling control of stiffened panels
NASA Astrophysics Data System (ADS)
Thompson, Danniella M.; Griffin, O. H., Jr.
1993-04-01
Materials systems and structures that can respond 'intelligently' to their environment are currently being proposed and investigated. A series of finite element analyses was performed to investigate the potential for active buckling control of two different stiffened panels by embedded shape memory alloy (SMA) rods. Changes in the predicted buckling load increased with the magnitude of the actuation level for a given structural concept. Increasing the number of actuators for a given concept yielded greater predicted increases in buckling load. Considerable control authority was generated with a small number of actuators, with greater authority demonstrated for those structural concepts where the activated SMA rods could develop greater forces and moments on the structure. Relatively simple and inexpensive analyses were performed with standard finite elements to determine such information, indicating the viability of these types of models for design purposes.
Active magnetic bearing control loop modeling for a finite element rotordynamics code
NASA Technical Reports Server (NTRS)
Genta, Giancarlo; Delprete, Cristiana; Carabelli, Stefano
1994-01-01
A mathematical model of an active electromagnetic bearing which includes the actuator, the sensor and the control system is developed and implemented in a specialized finite element code for rotordynamic analysis. The element formulation and its incorporation in the model of the machine are described in detail. A solution procedure, based on a modal approach in which the number of retained modes is controlled by the user, is then shown together with other procedures for computing the steady-state response to both static and unbalance forces. An example of application shows the numerical results obtained on a model of an electric motor suspended on a five active-axis magnetic suspension. The comparison of some of these results with the experimental characteristics of the actual system shows the ability of the present model to predict its performance.
Boundary element based multiresolution shape optimisation in electrostatics
NASA Astrophysics Data System (ADS)
Bandara, Kosala; Cirak, Fehmi; Of, Günther; Steinbach, Olaf; Zapletal, Jan
2015-09-01
We consider the shape optimisation of high-voltage devices subject to electrostatic field equations by combining fast boundary elements with multiresolution subdivision surfaces. The geometry of the domain is described with subdivision surfaces and different resolutions of the same geometry are used for optimisation and analysis. The primal and adjoint problems are discretised with the boundary element method using a sufficiently fine control mesh. For shape optimisation the geometry is updated starting from the coarsest control mesh with increasingly finer control meshes. The multiresolution approach effectively prevents the appearance of non-physical geometry oscillations in the optimised shapes. Moreover, there is no need for mesh regeneration or smoothing during the optimisation due to the absence of a volume mesh. We present several numerical experiments and one industrial application to demonstrate the robustness and versatility of the developed approach.
Systems and Methods of Coordination Control for Robot Manipulation
NASA Technical Reports Server (NTRS)
Chang, Chu-Yin (Inventor); English, James (Inventor); Tardella, Neil (Inventor); Bacon, James (Inventor)
2013-01-01
Disclosed herein are systems and methods for controlling robotic apparatus having several movable elements or segments coupled by joints. At least one of the movable elements can include one or more mobile bases, while the others can form one or more manipulators. One of the movable elements can be treated as an end effector for which a certain motion is desired. The end effector may include a tool, for example, or represent a robotic hand (or a point thereon), or one or more of the one or more mobile bases. In accordance with the systems and methods disclosed herein, movement of the manipulator and the mobile base can be controlled and coordinated to effect a desired motion for the end effector. In many cases, the motion can include simultaneously moving the manipulator and the mobile base.
NASA Astrophysics Data System (ADS)
Mitchell, Andrew C.; Brown, Giles H.
2007-01-01
SummaryWe present diurnal (i) 0.45 and 0.1 μm pore-size filtered and (ii) operationally defined labile particulate-associated major, minor and trace element concentrations and fluxes in glacial outflow waters draining Haut Glacier d'Arolla, Switzerland. We use speciation modelling (PHREEQCi) and water-suspended sediment interaction experiments are utilised under conditions analogous to the subglacial channellised hydrological system, in order to assess controls on, and the most suitable sampling methods to investigate short-term variations in the mode of major, minor and trace element species export from a glacierised headwater catchment. 0.45 μm pore-size filtered major ions, Sr and U are exported in glacial outflow waters predominately as mobile monovalent or divalent ions or as carbonate complexes, and are controlled by hydrological variations over diurnal cycles, exhibiting an inverse concentration with increasing meltwater discharge. Conversely, 0.45 μm pore-size filtered concentrations of most minor and trace elements ( e.g. Fe, Mn, Co, Ba and Pb) exhibit variations that are not strongly inter-correlated with meltwater discharge or suspended sediment concentrations (SSC) over diurnal periods. The use of 0.45 and 0.1 μm pore-size filter membranes indicates that significant colloidal material is not passing through the 0.45 μm pore-size filters, and these unsystematic variations are not a result of colloid measurement. Speciation modelling applied to meltwaters and observations during water-rock interaction experiments suggest that these unsystematic temporal variations reflect physicochemical controls. This includes sorption, and the oversaturation and precipitation of Fe and Al (oxi)hydroxides, and the co-precipitation of other species. Diurnal pH variations appear important in controlling such short-term physicochemical controls, which limits such species use for hydrological investigations. The percentage of total elemental fluxes exported as the labile particulate-associated flux (%PAF) for each minor and trace element changes dramatically between and during the diurnal cycles, reflecting species-specific sensitivity to hydrological and physicochemical controls. Hydrological interpretations of hydrochemical data must be made carefully when using chemical determinations by ICP-MS, since we demonstrate that measurements will comprise of any material that passes through the filter. This can lead to higher concentration measurements than if determined by ion chromatography, which measures truly ionic dissolved species.
Trace Elements and Healthcare: A Bioinformatics Perspective.
Zhang, Yan
2017-01-01
Biological trace elements are essential for human health. Imbalance in trace element metabolism and homeostasis may play an important role in a variety of diseases and disorders. While the majority of previous researches focused on experimental verification of genes involved in trace element metabolism and those encoding trace element-dependent proteins, bioinformatics study on trace elements is relatively rare and still at the starting stage. This chapter offers an overview of recent progress in bioinformatics analyses of trace element utilization, metabolism, and function, especially comparative genomics of several important metals. The relationship between individual elements and several diseases based on recent large-scale systematic studies such as genome-wide association studies and case-control studies is discussed. Lastly, developments of ionomics and its recent application in human health are also introduced.
NASA Technical Reports Server (NTRS)
Miller, Christopher J.
2011-01-01
A model reference nonlinear dynamic inversion control law has been developed to provide a baseline controller for research into simple adaptive elements for advanced flight control laws. This controller has been implemented and tested in a hardware-in-the-loop simulation and in flight. The flight results agree well with the simulation predictions and show good handling qualities throughout the tested flight envelope with some noteworthy deficiencies highlighted both by handling qualities metrics and pilot comments. Many design choices and implementation details reflect the requirements placed on the system by the nonlinear flight environment and the desire to keep the system as simple as possible to easily allow the addition of the adaptive elements. The flight-test results and how they compare to the simulation predictions are discussed, along with a discussion about how each element affected pilot opinions. Additionally, aspects of the design that performed better than expected are presented, as well as some simple improvements that will be suggested for follow-on work.
NASA Technical Reports Server (NTRS)
Dawson, Kenneth S.; Fortin, Paul E.
1987-01-01
The results of an integrated study of structures, aerodynamics, and controls using the STARS program on two advanced airplane configurations are presented. Results for the X-29A include finite element modeling, free vibration analyses, unsteady aerodynamic calculations, flutter/divergence analyses, and an aeroservoelastic controls analysis. Good correlation is shown between STARS results and various other verified results. The tasks performed on the Oblique Wing Research Aircraft include finite element modeling and free vibration analyses.
NASA Astrophysics Data System (ADS)
Li, X.; Li, S. W.
2012-07-01
In this paper, an efficient global optimization algorithm in the field of artificial intelligence, named Particle Swarm Optimization (PSO), is introduced into close range photogrammetric data processing. PSO can be applied to obtain the approximate values of exterior orientation elements under the condition that multi-intersection photography and a small portable plane control frame are used. PSO, put forward by an American social psychologist J. Kennedy and an electrical engineer R.C. Eberhart, is a stochastic global optimization method based on swarm intelligence, which was inspired by social behavior of bird flocking or fish schooling. The strategy of obtaining the approximate values of exterior orientation elements using PSO is as follows: in terms of image coordinate observed values and space coordinates of few control points, the equations of calculating the image coordinate residual errors can be given. The sum of absolute value of each image coordinate is minimized to be the objective function. The difference between image coordinate observed value and the image coordinate computed through collinear condition equation is defined as the image coordinate residual error. Firstly a gross area of exterior orientation elements is given, and then the adjustment of other parameters is made to get the particles fly in the gross area. After iterative computation for certain times, the satisfied approximate values of exterior orientation elements are obtained. By doing so, the procedures like positioning and measuring space control points in close range photogrammetry can be avoided. Obviously, this method can improve the surveying efficiency greatly and at the same time can decrease the surveying cost. And during such a process, only one small portable control frame with a couple of control points is employed, and there are no strict requirements for the space distribution of control points. In order to verify the effectiveness of this algorithm, two experiments are carried out. In the first experiment, images of a standard grid board are taken according to multi-intersection photography using digital camera. Three points or six points which are located on the left-down corner of the standard grid are regarded as control points respectively, and the exterior orientation elements of each image are computed through PSO, and compared with these elements computed through bundle adjustment. In the second experiment, the exterior orientation elements obtained from the first experiment are used as approximate values in bundle adjustment and then the space coordinates of other grid points on the board can be computed. The coordinate difference of grid points between these computed space coordinates and their known coordinates can be used to compute the accuracy. The point accuracy computed in above experiments are ±0.76mm and ±0.43mm respectively. The above experiments prove the effectiveness of PSO used in close range photogrammetry to compute approximate values of exterior orientation elements, and the algorithm can meet the requirement of higher accuracy. In short, PSO can get better results in a faster, cheaper way compared with other surveying methods in close range photogrammetry.
Trace elements in feed, manure, and manured soils.
Sheppard, S C; Sanipelli, B
2012-01-01
Modern animal feeds often include nutritional mineral supplements, especially elements such as Cu, P, Se, and Zn. Other sources of trace elements also occur in livestock systems, such as pharmaceutical use of As and Zn to control gut flora, Bi in dairy for mastitis control, and Cu as hoof dips. Additionally, potential exists for inadvertent inclusion of trace elements in feeds or manures. There is concern about long-term accumulation of trace elements in manured soil that may even exceed guideline "safe" concentrations. This project measured ∼60 elements in 124 manure samples from broiler, layer, turkey, swine grower, swine nursery, sow, dairy, and beef operations. The corresponding feeds were also analyzed. In general, concentrations in manure were two- to fivefold higher than those in feed: the manure/feed concentration ratios were relatively consistent for all the animal-essential elements and were numerically similar for many of the non-nutrient elements. To confirm the potential for accumulation in soil, total trace element concentrations were measured in the profiles of 10 manured and 10 adjacent unmanured soils. Concentrations of several elements were found to be elevated in the manured soils, with Zn (and P) the most common. One soil from a dairy standing yard had concentrations of B that exceeded soil health guideline concentrations. Given that the Cu/P and Zn/P ratios found in manure were greater than typically reported in harvested crop materials, these elements will accumulate in soil even if manure application rates are managed to prevent accumulation of P in soil. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.
Electronic Switch Arrays for Managing Microbattery Arrays
NASA Technical Reports Server (NTRS)
Mojarradi, Mohammad; Alahmad, Mahmoud; Sukumar, Vinesh; Zghoul, Fadi; Buck, Kevin; Hess, Herbert; Li, Harry; Cox, David
2008-01-01
Integrated circuits have been invented for managing the charging and discharging of such advanced miniature energy-storage devices as planar arrays of microscopic energy-storage elements [typically, microscopic electrochemical cells (microbatteries) or microcapacitors]. The architecture of these circuits enables implementation of the following energy-management options: dynamic configuration of the elements of an array into a series or parallel combination of banks (subarrarys), each array comprising a series of parallel combination of elements; direct addressing of individual banks for charging/or discharging; and, disconnection of defective elements and corresponding reconfiguration of the rest of the array to utilize the remaining functional elements to obtain the desited voltage and current performance. An integrated circuit according to the invention consists partly of a planar array of field-effect transistors that function as switches for routing electric power among the energy-storage elements, the power source, and the load. To connect the energy-storage elements to the power source for charging, a specific subset of switches is closed; to connect the energy-storage elements to the load for discharging, a different specific set of switches is closed. Also included in the integrated circuit is circuitry for monitoring and controlling charging and discharging. The control and monitoring circuitry, the switching transistors, and interconnecting metal lines are laid out on the integrated-circuit chip in a pattern that registers with the array of energy-storage elements. There is a design option to either (1) fabricate the energy-storage elements in the corresponding locations on, and as an integral part of, this integrated circuit; or (2) following a flip-chip approach, fabricate the array of energy-storage elements on a separate integrated-circuit chip and then align and bond the two chips together.
Simulation results of automatic restructurable flight control system concepts
NASA Technical Reports Server (NTRS)
Weiss, J. L.; Looze, D. P.; Eterno, J. S.; Ostroff, A.
1986-01-01
The restructurable flight control system (RFCS) described by Weiss et al. (1986) is reviewed, and several results of an extensive six degrees of freedom nonlinear simulation of several aspects of this system are reported. It is concluded that the nontraditional use of standard control surfaces in a nominal feedback control system to spread control authority among many redundant control elements provides a significant amount of fault tolerance without any use of restructuring techniques. The use of new feedback gains alone following a failure can provide significantly improved recovery as long as the control elements remain within their travel limits and as long as uncertainty about the failure identity is properly handled. The use of the feed-forward trim solution in conjunction with redesigned feedback gains allows recovery to take place even when significant control saturation occurs.
Epigenetic control of transposon transcription and mobility in Arabidopsis.
Bucher, Etienne; Reinders, Jon; Mirouze, Marie
2012-11-01
The mobility of genetic elements called transposable elements (TEs) was discovered half a century ago by Barbara McClintock. Although she had recognized them as chromosomal controlling elements, for much of the consequent time TEs were primarily considered as parasites of the host genome. However the recent explosion of discoveries in the fields of genomics and epigenetics have unambiguously shown the importance of TEs in genome function and evolution. Bursts of endogenous TEs have been reported in plants with epigenetic misregulation, revealing the molecular mechanisms underlying their control. We review here the different steps in TE invasion of the host genome involving epigenetic control and environmental stress responses. As TEs propagate in plant genomes and attract epigenetic marks, their neo-insertions can lead to the formation of new, heritable epigenetic variants (epialleles) of genes in their vicinity and impact on host gene regulatory networks. The epigenetic interplay between TE and genes thus plays a crucial role in the TE-host co-evolution. Copyright © 2012 Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Hasan, Mohammed Adnan; Rashmi, S.; Esther, A. Carmel Mary; Bhavanisankar, Prudhivi Yashwantkumar; Sherikar, Baburao N.; Sridhara, N.; Dey, Arjun
2018-03-01
The feasibility of utilizing commercially available silica aerogel-based flexible composite blankets as passive thermal control element in applications such as extraterrestrial environments is investigated. Differential scanning calorimetry showed that aerogel blanket was thermally stable over - 150 to 126 °C. The outgassing behavior, e.g., total mass loss, collected volatile condensable materials, water vapor regained and recovered mass loss, was within acceptable range recommended for the space applications. ASTM tension and tear tests confirmed the material's mechanical integrity. The thermo-optical properties remained nearly unaltered in simulated space environmental tests such as relative humidity, thermal cycling and thermo-vacuum tests and confirmed the space worthiness of the aerogel. Aluminized Kapton stitched or anchored to the blanket could be used to control the optical transparency of the aerogel. These outcomes highlight the potential of commercial aerogel composite blankets as passive thermal control element in spacecraft. Structural and chemical characterization of the material was also done using scanning electron microscopy, Fourier transform infrared spectroscopy and x-ray photoelectron spectroscopy.
Finite element based electric motor design optimization
NASA Technical Reports Server (NTRS)
Campbell, C. Warren
1993-01-01
The purpose of this effort was to develop a finite element code for the analysis and design of permanent magnet electric motors. These motors would drive electromechanical actuators in advanced rocket engines. The actuators would control fuel valves and thrust vector control systems. Refurbishing the hydraulic systems of the Space Shuttle after each flight is costly and time consuming. Electromechanical actuators could replace hydraulics, improve system reliability, and reduce down time.
Orbiter subsystem hardware/software interaction analysis. Volume 8: Forward reaction control system
NASA Technical Reports Server (NTRS)
Becker, D. D.
1980-01-01
The results of the orbiter hardware/software interaction analysis for the AFT reaction control system are presented. The interaction between hardware failure modes and software are examined in order to identify associated issues and risks. All orbiter subsystems and interfacing program elements which interact with the orbiter computer flight software are analyzed. The failure modes identified in the subsystem/element failure mode and effects analysis are discussed.
Technology Insertion for Recapitalization of Legacy Systems
2017-09-28
Inspection Two methods of thermal wave inspection were investigated. In one method, an electric current was run through the torsion bar to heat the...Material Properties and the Controlled Shot Peening of Turbine Blades ". Metal Behaviour and Surface Engineering, IIIT-lnternational I 989 18 Richard...the presence of a singularity, direct control of the mesh size was used to set the element dimensions over several runs of the analysis. The element
NASA Technical Reports Server (NTRS)
Wey, Thomas; Liu, Nan-Suey
2015-01-01
This paper summarizes the procedures of (1) generating control volumes anchored at the nodes of a mesh; and (2) generating staggered control volumes via mesh reconstructions, in terms of either mesh realignment or mesh refinement, as well as presents sample results from their applications to the numerical solution of a single-element LDI combustor using a releasable edition of the National Combustion Code (NCC).
2001-06-01
Algorithms for Vertical Fin Buffeting Using Strain Actuation DISTRIBUTION: Approved for public release, distribution unlimited This paper is part of the...UNCLASSIFIED 8-1 Finite Element Approach for the Design of Control Algorithms for Vertical Fin Buffeting Using Strain Actuation Fred Nitzsche...groups), the disturbance (buffet load), and the two output variables (a choice among four Introduction accelerometers and five strain - gauge positions
Dealing with the time-varying parameter problem of robot manipulators performing path tracking tasks
NASA Technical Reports Server (NTRS)
Song, Y. D.; Middleton, R. H.
1992-01-01
Many robotic applications involve time-varying payloads during the operation of the robot. It is therefore of interest to consider control schemes that deal with time-varying parameters. Using the properties of the element by element (or Hadarmad) product of matrices, we obtain the robot dynamics in parameter-isolated form, from which a new control scheme is developed. The controller proposed yields zero asymptotic tracking errors when applied to robotic systems with time-varying parameters by using a switching type control law. The results obtained are global in the initial state of the robot, and can be applied to rapidly varying systems.
Space Station environmental control and life support system distribution and loop closure studies
NASA Technical Reports Server (NTRS)
Humphries, William R.; Reuter, James L.; Schunk, Richard G.
1986-01-01
The NASA Space Station's environmental control and life support system (ECLSS) encompasses functional elements concerned with temperature and humidity control, atmosphere control and supply, atmosphere revitalization, fire detection and suppression, water recovery and management, waste management, and EVA support. Attention is presently given to functional and physical module distributions of the ECLSS among these elements, with a view to resource requirements and safety implications. A strategy of physical distribution coupled with functional centralization is for the air revitalization and water reclamation systems. Also discussed is the degree of loop closure desirable in the initial operational capability status Space Station's oxygen and water reclamation loops.
System-Level Integrated Circuit (SLIC) Technology Development for Phased Array Antenna Applications
NASA Technical Reports Server (NTRS)
Windyka, John A.; Zablocki, Ed G.
1997-01-01
This report documents the efforts and progress in developing a 'system-level' integrated circuit, or SLIC, for application in advanced phased array antenna systems. The SLIC combines radio-frequency (RF) microelectronics, digital and analog support circuitry, and photonic interfaces into a single micro-hybrid assembly. Together, these technologies provide not only the amplitude and phase control necessary for electronic beam steering in the phased array, but also add thermally-compensated automatic gain control, health and status feedback, bias regulation, and reduced interconnect complexity. All circuitry is integrated into a compact, multilayer structure configured for use as a two-by-four element phased array module, operating at 20 Gigahertz, using a Microwave High-Density Interconnect (MHDI) process. The resultant hardware is constructed without conventional wirebonds, maintains tight inter-element spacing, and leads toward low-cost mass production. The measured performances and development issues associated with both the two-by-four element module and the constituent elements are presented. Additionally, a section of the report describes alternative architectures and applications supported by the SLIC electronics. Test results show excellent yield and performance of RF circuitry and full automatic gain control for multiple, independent channels. Digital control function, while suffering from lower manufacturing yield, also proved successful.
Method for producing nanocrystalline multicomponent and multiphase materials
Eastman, Jeffrey A.; Rittner, Mindy N.; Youngdahl, Carl J.; Weertman, Julia R.
1998-01-01
A process for producing multi-component and multiphase nanophase materials is provided wherein a plurality of elements are vaporized in a controlled atmosphere, so as to facilitate thorough mixing, and then condensing and consolidating the elements. The invention also provides for a multicomponent and multiphase nanocrystalline material of specified elemental and phase composition having component grain sizes of between approximately 1 nm and 100 nm. This material is a single element in combination with a binary compound. In more specific embodiments, the single element in this material can be a transition metal element, a non-transition metal element, a semiconductor, or a semi-metal, and the binary compound in this material can be an intermetallic, an oxide, a nitride, a hydride, a chloride, or other compound.
Wetland Hydrological Connectivity: A Classification Approach and Continental Assessment
Connectivity has become a major focus of hydrological and ecological studies. Connectivity influences fluxes between landscape elements, while isolation reduces flows between elements. Thus connectivity can be an important characteristic controlling ecosystem services. Hydrolo...
Design Issues for Producing Effective Multimedia Presentations.
ERIC Educational Resources Information Center
Mason, Lisa D.
1997-01-01
Discusses design issues for interactive multimedia. Notes that technical communication instructors must consider navigational aids, the degree of control a user should have, audio cues, color and typographical elements, visual elements, and copyright issues. (RS)
Adaptation of a Control Center Development Environment for Industrial Process Control
NASA Technical Reports Server (NTRS)
Killough, Ronnie L.; Malik, James M.
1994-01-01
In the control center, raw telemetry data is received for storage, display, and analysis. This raw data must be combined and manipulated in various ways by mathematical computations to facilitate analysis, provide diversified fault detection mechanisms, and enhance display readability. A development tool called the Graphical Computation Builder (GCB) has been implemented which provides flight controllers with the capability to implement computations for use in the control center. The GCB provides a language that contains both general programming constructs and language elements specifically tailored for the control center environment. The GCB concept allows staff who are not skilled in computer programming to author and maintain computer programs. The GCB user is isolated from the details of external subsystem interfaces and has access to high-level functions such as matrix operators, trigonometric functions, and unit conversion macros. The GCB provides a high level of feedback during computation development that improves upon the often cryptic errors produced by computer language compilers. An equivalent need can be identified in the industrial data acquisition and process control domain: that of an integrated graphical development tool tailored to the application to hide the operating system, computer language, and data acquisition interface details. The GCB features a modular design which makes it suitable for technology transfer without significant rework. Control center-specific language elements can be replaced by elements specific to industrial process control.
Development and applications of a flat triangular element for thin laminated shells
NASA Astrophysics Data System (ADS)
Mohan, P.
Finite element analysis of thin laminated shells using a three-noded flat triangular shell element is presented. The flat shell element is obtained by combining the Discrete Kirchhoff Theory (DKT) plate bending element and a membrane element similar to the Allman element, but derived from the Linear Strain Triangular (LST) element. The major drawback of the DKT plate bending element is that the transverse displacement is not explicitly defined within the interior of the element. In the present research, free vibration analysis is performed both by using a lumped mass matrix and a so called consistent mass matrix, obtained by borrowing shape functions from an existing element, in order to compare the performance of the two methods. Several numerical examples are solved to demonstrate the accuracy of the formulation for both small and large rotation analysis of laminated plates and shells. The results are compared with those available in the existing literature and those obtained using the commercial finite element package ABAQUS and are found to be in good agreement. The element is employed for two main applications involving large flexible structures. The first application is the control of thermal deformations of a spherical mirror segment, which is a segment of a multi-segmented primary mirror used in a space telescope. The feasibility of controlling the surface distortions of the mirror segment due to arbitrary thermal fields, using discrete and distributed actuators, is studied. The second application is the analysis of an inflatable structure, being considered by the US Army for housing vehicles and personnel. The updated Lagrangian formulation of the flat shell element has been developed primarily for the nonlinear analysis of the tent structure, since such a structure is expected to undergo large deformations and rotations under the action of environmental loads like the wind and snow loads. The follower effects of the pressure load have been included in the updated Lagrangian formulation of the flat shell element and have been validated using standard examples in the literature involving deformation-dependent pressure loads. The element can be used to obtain the nonlinear response of the tent structure under wind and snow loads. (Abstract shortened by UMI.)
NASA Technical Reports Server (NTRS)
Ostroff, A. J.; Hueschen, R. M.
1984-01-01
The ability of a pilot to reconfigure the control surfaces on an airplane after a failure, allowing the airplane to recover to a safe condition, becomes more difficult with increasing airplane complexity. Techniques are needed to stabilize and control the airplane immediately after a failure, allowing the pilot more time to make longer range decisions. This paper presents a baseline design of a discrete multivariable control law using four controls for the longitudinal channel of a B-737. Non-reconfigured and reconfigured control laws are then evaluated, both analytically and by means of a digital airplane simulation, for three individual control element failures (stabilizer, elevator, spoilers). The simulation results are used to evaluate the effectiveness of the control reconfiguration on tracking ability during the approach and landing phase of flight with severe windshear and turbulence disturbing the airplane dynamics.
Vibration control in statically indeterminate adaptive truss structures
NASA Technical Reports Server (NTRS)
Baycan, C. M.; Utku, Senol; Wada, Ben K.
1993-01-01
In this work vibration control of statically indeterminate adaptive truss structures is investigated. Here, the actuators (i.e., length adjusting devices) that are used for vibration control, work against the axial forces caused by the inertial forces. In statically determinate adaptive trusses no axial force is induced by the actuation. The control problem in statically indeterminate trusses may be dominated by the actuation-induced axial element forces. The creation of actuation-induced axial forces puts the system to a higher energy state, thus aggravates the controls. It is shown that by the usage of sufficient number of slave actuators in addition to the actual control actuators, the actuation-induced axial element forces can be nullified, and the control problem of the statically indeterminate adaptive truss problem is reduced to that of a statically determinate one. It is also shown that the usage of slave actuators saves a great amount of control energy and provides robustness for the controls.
Kellogg, Harvey J.; Holm, Robert O.
1983-01-01
A groove refinishing tool which utilizes a finishing wheel which is controlled by an air grinder motor. The air grinder motor is mounted on a main body section which is pivotally attached to a shoe element. The shoe element contains guide pins which guide the shoe element on the groove to be refinished. Application of pressure on the main body element compresses a weight counterbalance spring to extend the finishing wheel through the shoe element to refinish the groove surface. A window is provided for viewing the refinishing operation. Milling operations can also be performed by replacing the finishing wheel with a milling wheel.
The 'North American shale composite' - Its compilation, major and trace element characteristics
NASA Technical Reports Server (NTRS)
Gromet, L. P.; Dymek, R. F.; Haskin, L. A.; Korotev, R. L.
1984-01-01
North American shale composite (NASC) major element composition and compilation are presented, together with rare earth element (REE) redeterminations obtained by high precision analytical methods. The major element composition of the NASC compares closely with other average shale compositions, and significant portions of the REE and some other trace elements are contained in minor phases. The uneven REE distribution in NASC powder appears to yield the heterogeneity in analyzed aliquants. REE distributions of detrital sediments may to some extent be dependent on their minor mineral assemblages and the sedimentological factors controlling these assemblages.
Hynynen, Kullervo; Yin, Jianhua
2009-03-01
A method that uses lateral coupling to reduce the electrical impedance of small transducer elements in generating ultrasound waves was tested. Cylindrical, radially polled transducer elements were driven at their length resonance frequency. Computer simulation and experimental studies showed that the electrical impedance of the transducer element could be controlled by the cylinder wall thickness, while the operation frequency was determined by the cylinder length. Acoustic intensity (averaged over the cylinder diameter) over 10 W / cm(2) (a therapeutically relevant intensity) was measured from these elements.
NASA Technical Reports Server (NTRS)
Lai, Steven H.-Y.
1992-01-01
A variational principle and a finite element discretization technique were used to derive the dynamic equations for a high speed rotating flexible beam-mass system embedded with piezo-electric materials. The dynamic equation thus obtained allows the development of finite element models which accommodate both the original structural element and the piezoelectric element. The solutions of finite element models provide system dynamics needed to design a sensing system. The characterization of gyroscopic effect and damping capacity of smart rotating devices are addressed. Several simulation examples are presented to validate the analytical solution.
NASA Technical Reports Server (NTRS)
Buehler, Martin G. (Inventor)
1988-01-01
A set of addressable test structures, each of which uses addressing schemes to access individual elements of the structure in a matrix, is used to test the quality of a wafer before integrated circuits produced thereon are diced, packaged and subjected to final testing. The electrical characteristic of each element is checked and compared to the electrical characteristic of all other like elements in the matrix. The effectiveness of the addressable test matrix is in readily analyzing the electrical characteristics of the test elements and in providing diagnostic information.
Nuclear Security: Quantifying Late Detection in MC&A
DOE Office of Scientific and Technical Information (OSTI.GOV)
Singh, Surinder Paul; Gibbs, Philip W.; Bultz, Garl A.
2014-03-01
The objectives of this presentation are to understand the concept of late detection; review the statistics used in MC&A; specify the Pd and timelines for Pd for MC&A elements for item inventories; review elements of process control as they relate to bulk processes; and specify the timelines and detection thresholds for Pd for MC&A elements for bulk or Processing Operations.
Distribution of elements in individual blood cells in metabolic disorders at the cellular level
NASA Astrophysics Data System (ADS)
Johansson, Erland; Lindh, Ulf
1985-08-01
In comparison with controls neutrophil granulocytes from Rheumatoid arthritis (RA), Infantile Neuronal Ceroid Lipofuscinosis (INCL), Chronic Lymphatic Leukemia (L) and Aplastic Anemia (AA) displayed significant alterations in essential and non-essential elements which might be interpreted as fingerprints of these deseases. The neutrophils from RA patients displayed alterations in the concentrations of iron, calcium, strontium, manganese, zinc and copper. INCL displayed alterations in the concentrations of iron and copper but in the INCL disease the iron concentration was about 2 times higher than in RA. In leukemia, aluminium was observed but not in the controls (< 0.5 μg/ g). The zinc concentration was lowered in leukemia. Aplastic anemia displayed alterations in zirconium, arsenic, molybdenum, iron and zinc. The platelets from RA, INCL, L and AA patients also displayed alterations in the elemental profiles. The platelets from AA patients displayed a unique elemental distribution of arsenic, zirconium and molybdenum. The elemental profiles of the thrombocytes and neutrophils might be used as a complement in the diagnosis of the examined diseases and in therapy the elemental profile might be used to monitor drugs at the cellular level.
The Relationship of Aluminium and Silver to Neural Tube Defects; a Case Control
Ramírez-Altamirano, María de Jesús; Fenton-Navarro, Patricia; Sivet-Chiñas, Elvira; Harp-Iturribarria, Flor de María; Martínez-Cruz, Ruth; Cruz, Pedro Hernández; Cruz, Margarito Martínez; Pérez-Campos, Eduardo
2012-01-01
Objective The purpose of this study was to identify the relationship of neurotoxic inorganic elements in the hair of patients with the diagnosis of Neural Tube Defects. Our initial hypothesis was that neurotoxic inorganic elements were associated with Neural Tube Defects. Methods Twenty-three samples of hair from newborns were obtained from the General Hospital, “Aurelio Valdivieso” in the city of Oaxaca, Mexico. The study group included 8 newborn infants with neural tube pathology. The control group was composed of 15 newborns without this pathology. The presence of inorganic elements in the hair samples was determined by inductively-coupled plasma spectroscopy (spectroscopic emission of the plasma). Findings The population of newborns with Neural Tube Defects showed significantly higher values of the following elements than the control group: Aluminium, Neural Tube Defects 152.77±51.06 µg/g, control group 76.24±27.89 µg/g; Silver, Neural Tube Defects 1.45±0.76, control group 0.25±0.53 µg/g; Potassium, Neural Tube Defects 553.87±77.91 µg/g, control group 341.13±205.90 µg/g. Association was found at 75 percentile between aluminium plus silver, aluminium plus potassium, silver plus potassium, and potassium plus sodium. Conclusion In the hair of newborns with Neural Tube Defects, the following metals were increased: aluminium, silver. Given the neurotoxicity of the same, and association of Neural Tube Defects with aluminum and silver, one may infer that they may be participating as factors in the development of Neural Tube Defects. PMID:23400307
Overview of NASA's Thermal Control System Development for Exploration Project
NASA Technical Reports Server (NTRS)
Stephan, Ryan A.
2011-01-01
The now-cancelled Constellation Program included the Orion, Altair, and Lunar Surface Systems project offices. The first two elements, Orion and Altair, were planned to be manned space vehicles while the third element was much more diverse and included several sub-elements. Among other things, these sub-elements were Rovers and a Lunar Habitat. The planned missions involving these systems and vehicles included several risks and design challenges. Due to the unique thermal operating environment, many of these risks and challenges were associated with the vehicles thermal control system. NASA s Exploration Technology Development Program (ETDP) consisted of various technology development projects. The project chartered with mitigating the aforementioned thermal risks and design challenges was the Thermal Control System Development for Exploration Project. These risks and design challenges were being addressed through a rigorous technology development process that was planned to culminate with an integrated thermal control system test. Although the technologies being developed were originally aimed towards mitigating specific Constellation risks, the technology development process is being continued within a new program. This continued effort is justified by the fact that many of the technologies are generically applicable to future spacecraft thermal control systems. The current paper summarizes the development efforts being performed by the technology development project. The development efforts involve heat acquisition and heat rejection hardware including radiators, heat exchangers, and evaporators. The project has also been developing advanced phase change material heat sinks and performing a material compatibility assessment for a promising thermal control system working fluid. The to-date progress and lessons-learned from these development efforts will be discussed throughout the paper.
Nonlinear Dynamic Inversion Baseline Control Law: Architecture and Performance Predictions
NASA Technical Reports Server (NTRS)
Miller, Christopher J.
2011-01-01
A model reference dynamic inversion control law has been developed to provide a baseline control law for research into adaptive elements and other advanced flight control law components. This controller has been implemented and tested in a hardware-in-the-loop simulation; the simulation results show excellent handling qualities throughout the limited flight envelope. A simple angular momentum formulation was chosen because it can be included in the stability proofs for many basic adaptive theories, such as model reference adaptive control. Many design choices and implementation details reflect the requirements placed on the system by the nonlinear flight environment and the desire to keep the system as basic as possible to simplify the addition of the adaptive elements. Those design choices are explained, along with their predicted impact on the handling qualities.
Generation of electrical power
Hursen, Thomas F.; Kolenik, Steven A.; Purdy, David L.
1976-01-01
A heat-to-electricity converter is disclosed which includes a radioactive heat source and a thermoelectric element of relatively short overall length capable of delivering a low voltage of the order of a few tenths of a volt. Such a thermoelectric element operates at a higher efficiency than longer higher-voltage elements; for example, elements producing 6 volts. In the generation of required power, thermoelectric element drives a solid-state converter which is controlled by input current rather than input voltage and operates efficiently for a high signal-plus-noise to signal ratio of current. The solid-state converter has the voltage gain necessary to deliver the required voltage at the low input of the thermoelectric element.
Active terahertz metamaterial devices
Chen, Houtong; Padilla, Willie John; Averitt, Richard Douglas; O'Hara, John F.; Lee, Mark
2010-11-02
Metamaterial structures are taught which provide for the modulation of terahertz frequency signals. Each element within an array of metamaterial (MM) elements comprises multiple loops and at least one gap. The MM elements may comprise resonators with conductive loops and insulated gaps, or the inverse in which insulated loops are present with conductive gaps; each providing useful transmissive control properties. The metamaterial elements are fabricated on a semiconducting substrate configured with a means of enhancing or depleting electrons from near the gaps of the MM elements. An on to off transmissivity ratio of about 0.5 is achieved with this approach. Embodiments are described in which the MM elements incorporated within a Quantum Cascade Laser (QCL) to provide surface emitting (SE) properties.
Vortex Generators to Control Boundary Layer Interactions
NASA Technical Reports Server (NTRS)
Babinsky, Holger (Inventor); Loth, Eric (Inventor); Lee, Sang (Inventor)
2014-01-01
Devices for generating streamwise vorticity in a boundary includes various forms of vortex generators. One form of a split-ramp vortex generator includes a first ramp element and a second ramp element with front ends and back ends, ramp surfaces extending between the front ends and the back ends, and vertical surfaces extending between the front ends and the back ends adjacent the ramp surfaces. A flow channel is between the first ramp element and the second ramp element. The back ends of the ramp elements have a height greater than a height of the front ends, and the front ends of the ramp elements have a width greater than a width of the back ends.
Principles of Sterilization of Mars Descent Vehicle Elements
NASA Astrophysics Data System (ADS)
Trofimov, Vladislav; Deshevaya, Elena; Khamidullina, N.; Kalashnikov, Viktor
Due to COSPAR severe requirements to permissible microbiological contamination of elements of down-to-Mars S/C as well as complexity of their chemical composition and structure the exposure of such S/C elements to antimicrobial treatment (sterilization) at their integration requires application of a wide set of methods: chemical, ultraviolet, radiation. The report describes the analysis of all the aspects of applicable methods of treatment for cleaning of elements’ surfaces and inner contents from microbiota. The analysis showed that the most important, predictable and controllable method is radiation processing (of the elements which don’t change their properties after effective treatment). The experience of ionizing radiation application for sterilization of products for medicine, etc. shows that, depending on initial microbial contamination of lander elements, the required absorbed dose can be within the range 12 ÷ 35 kGr. The analysis of the effect of irregularity of radiation absorption in complex structure elements to the choice of radiation methodology was made and the algorithm of the choice of effective conditions of radiation treatment and control of sterilization efficiency was suggested. The important phase of establishing of the effective condition of each structure element treatment is experimental verification of real microbiological contamination in terms of S/C integration, contamination maximum decrease using another cleaning procedures (mechanical, chemical, ultraviolet) and determination of radiation resistance of spore microorganisms typical for the shops of space technology manufacturing and assembling. Proceeding from three parameters (irregularity of radiation absorption in a concrete element, its initial microbial contamination and resistance of microorganisms to the effect of radiation) the condition of the packed object sterilization is chosen, the condition that prevents secondary contamination, ensures given reliability of the treatment without final experimental microbiological verification only by simple control of the absorbed dose at critical points. All the process phases (from the choice of treatment conditions to provision of the procedure safety) are strictly regulated by Russian legislation in accordance with international standards.
Composition of water and suspended sediment in streams of urbanized subtropical watersheds in Hawaii
De Carlo, E. H.; Beltran, V.L.; Tomlinson, M.S.
2004-01-01
Urbanization on the small subtropical island of Oahu, Hawaii provides an opportunity to examine how anthropogenic activity affects the composition of material transferred from land to ocean by streams. This paper investigates the variability in concentrations of trace elements (Pb, Zn, Cu, Ba, Co, As, Ni, V and Cr) in streams of watersheds on Oahu, Hawaii. The focus is on water and suspended particulate matter collected from the Ala Wai Canal watershed in Honolulu and also the Kaneohe Stream watershed. As predicted, suspended particulate matter controls most trace element transport. Elements such as Pb, Zn, Cu, Ba and Co exhibit increased concentrations within urbanized portions of the watersheds. Particulate concentrations of these elements vary temporally during storms owing to input of road runoff containing elevated concentrations of elements associated with vehicular traffic and other anthropogenic activities. Enrichments of As in samples from predominantly conservation areas are interpreted as reflecting agricultural use of fertilizers at the boundaries of urban and conservation lands. Particulate Ni, V and Cr exhibit distributions during storm events that suggest a mineralogical control. Principal component analysis of particulate trace element concentrations establishes eigenvalues that account for nearly 80% of the total variance and separates trace elements into 3 factors. Factor 1 includes Pb, Zn, Cu, Ba and Co, interpreted to represent metals with an urban anthropogenic enrichment. Factor 2 includes Ni, V and Cr, elements whose concentrations do not appear to derive from anthropogenic activity and is interpreted to reflect mineralogical control. Another, albeit less significant, anthropogenic factor includes As, Cd and U and is thought to represent agricultural inputs. Samples collected during a storm derived from an offshore low-pressure system suggest that downstream transport of upper watershed material during tradewind-derived rains results in a 2-3-fold dilution of the particulate concentrations of Pb, Zn and Cu in the Ala Wai canal watershed. ?? 2004 Elsevier Ltd. All rights reserved.
Thyroid functions and trace elements in pediatric patients with exogenous obesity.
Cayir, Atilla; Doneray, Hakan; Kurt, Nezahat; Orbak, Zerrin; Kaya, Avni; Turan, Mehmet Ibrahim; Yildirim, Abdulkadir
2014-02-01
Obesity is a multifactorial disease developing following impairment of the energy balance. The endocrine system is known to be affected by the condition. Serum thyroid hormones and trace element levels have been shown to be affected in obese children. Changes in serum thyroid hormones may result from alterations occurring in serum trace element levels. The aim of this study was to evaluate whether or not changes in serum thyroid hormone levels in children with exogenous obesity are associated with changes in trace element levels. Eighty-five children diagnosed with exogenous obesity constituted the study group, and 24 age- and sex-matched healthy children made up the control group. Serum thyroid stimulating hormone (TSH), free thyroxine (fT4), free triiodothyronine (fT3), thyroglobulin (TG), selenium (Se), zinc (Zn), copper (Cu), and manganese (Mn) levels in the study group were measured before and at the third and sixth months of treatment, and once only in the control group. Pretreatment fT4 levels in the study group rose significantly by the sixth month (p = 0.006). Zn levels in the patient group were significantly low compared to the control group (p = 0.009). Mn and Se levels in the obese children before and at the third and sixth months of treatment were significantly higher than those of the control group (p = 0.001, p = 0.001). In conclusion, fT4, Zn, Cu, Mn, and Se levels are significantly affected in children diagnosed with exogenous obesity. The change in serum fT4 levels is not associated with changes in trace element concentrations.
Synchrotron Imaging Computations on the Grid without the Computing Element
NASA Astrophysics Data System (ADS)
Curri, A.; Pugliese, R.; Borghes, R.; Kourousias, G.
2011-12-01
Besides the heavy use of the Grid in the Synchrotron Radiation Facility (SRF) Elettra, additional special requirements from the beamlines had to be satisfied through a novel solution that we present in this work. In the traditional Grid Computing paradigm the computations are performed on the Worker Nodes of the grid element known as the Computing Element. A Grid middleware extension that our team has been working on, is that of the Instrument Element. In general it is used to Grid-enable instrumentation; and it can be seen as a neighbouring concept to that of the traditional Control Systems. As a further extension we demonstrate the Instrument Element as the steering mechanism for a series of computations. In our deployment it interfaces a Control System that manages a series of computational demanding Scientific Imaging tasks in an online manner. The instrument control in Elettra is done through a suitable Distributed Control System, a common approach in the SRF community. The applications that we present are for a beamline working in medical imaging. The solution resulted to a substantial improvement of a Computed Tomography workflow. The near-real-time requirements could not have been easily satisfied from our Grid's middleware (gLite) due to the various latencies often occurred during the job submission and queuing phases. Moreover the required deployment of a set of TANGO devices could not have been done in a standard gLite WN. Besides the avoidance of certain core Grid components, the Grid Security infrastructure has been utilised in the final solution.
Geology of photo linear elements, Great Divide Basin, Wyoming
NASA Technical Reports Server (NTRS)
Blackstone, D. L., Jr.
1973-01-01
The author has identified the following significant results. Ground examination of photo linear elements in the Great Divide Basin, Wyoming indicates little if any tectonic control. Aeolian aspects are more widespread and pervasive than previously considered.
Wetland Hydrological Connectivity: A Classification Approach and United States Assessment
Connectivity has become a major focus of hydrological and ecological studies. Connectivity influences fluxes between landscape elements, while isolation reduces flows between elements. Thus connectivity can be an important characteristic controlling ecosystem services. Hydrolo...
Nuclear Thermal Rocket Element Environmental Simulator (NTREES)
NASA Technical Reports Server (NTRS)
Schoenfeld, Michael
2009-01-01
A detailed description of the Nuclear Thermal Rocket Element Environmental Simulator (NTREES) is presented. The contents include: 1) Design Requirements; 2) NTREES Layout; 3) Data Acquisition and Control System Schematics; 4) NTREES System Schematic; and 5) NTREES Setup.
Analysis of on-orbit thermal characteristics of the 15-meter hoop/column antenna
NASA Technical Reports Server (NTRS)
Andersen, Gregory C.; Farmer, Jeffery T.; Garrison, James
1987-01-01
In recent years, interest in large deployable space antennae has led to the development of the 15 meter hoop/column antenna. The thermal environment the antenna is expected to experience during orbit is examined and the temperature distributions leading to reflector surface distortion errors are determined. Two flight orientations corresponding to: (1) normal operation, and (2) use in a Shuttle-attached flight experiment are examined. A reduced element model was used to determine element temperatures at 16 orbit points for both flight orientations. The temperature ranged from a minimum of 188 K to a maximum of 326 K. Based on the element temperatures, orbit position leading to possible worst case surface distortions were determined, and the subsequent temperatures were used in a static finite element analysis to quantify surface control cord deflections. The predicted changes in the control cord lengths were in the submillimeter ranges.
Integrated unaligned resonant modulator tuning
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zortman, William A.; Lentine, Anthony L.
Methods and systems for tuning a resonant modulator are disclosed. One method includes receiving a carrier signal modulated by the resonant modulator with a stream of data having an approximately equal number of high and low bits, determining an average power of the modulated carrier signal, comparing the average power to a predetermined threshold, and operating a tuning device coupled to the resonant modulator based on the comparison of the average power and the predetermined threshold. One system includes an input structure, a plurality of processing elements, and a digital control element. The input structure is configured to receive, frommore » the resonant modulator, a modulated carrier signal. The plurality of processing elements are configured to determine an average power of the modulated carrier signal. The digital control element is configured to operate a tuning device coupled to the resonant modulator based on the average power of the modulated carrier signal.« less
Self-actuating reactor shutdown system
Barrus, Donald M.; Brummond, Willian A; Peterson, Leslie F.
1988-01-01
A control system for the automatic or self-actuated shutdown or "scram" of a nuclear reactor. The system is capable of initiating scram insertion by a signal from the plant protection system or by independent action directly sensing reactor conditions of low-flow or over-power. Self-actuation due to a loss of reactor coolant flow results from a decrease of pressure differential between the upper and lower ends of an absorber element. When the force due to this differential falls below the weight of the element, the element will fall by gravitational force to scram the reactor. Self-actuation due to high neutron flux is accomplished via a valve controlled by an electromagnet and a thermionic diode. In a reactor over-power, the diode will be heated to a change of state causing the electromagnet to be shorted thereby actuating the valve which provides the changed flow and pressure conditions required for scramming the absorber element.
The pioneer projects: Economical exploration of the solar system
NASA Technical Reports Server (NTRS)
Spahr, J. R.; Hall, C. F.
1975-01-01
The interplanetary Pioneer missions are reviewed in terms of management implications and cost control. The responsibilities, organizational structure, and management practices of the Pioneer Projects are presented. The lines of authority and areas of responsibility of the principal organizational elements supporting the Pioneer missions are identified, and the methods employed for maintaining effective and timely interactions among these elements are indicated. The technical and administrative functions of the various organizational elements of the Pioneer Project Office at Ames Research Center are described in terms of their management responsibilities and interactions with other elements of the Project Office and with external organizations having Pioneer Project responsibilities. The management and control of activities prior to and during the hardware procurement phase are described to indicate the basis for obtaining visibility of the technical progress, utilization of resources, and cost performance of the contractors and other institutions supporting the Pioneer projects.
NASA Astrophysics Data System (ADS)
Wang, Juan; Wang, Jian; Li, Lijuan; Zhou, Kun
2014-08-01
In order to solve the information fusion, process integration, collaborative design and manufacturing for ultra-precision optical elements within life-cycle management, this paper presents a digital management platform which is based on product data and business processes by adopting the modern manufacturing technique, information technique and modern management technique. The architecture and system integration of the digital management platform are discussed in this paper. The digital management platform can realize information sharing and interaction for information-flow, control-flow and value-stream from user's needs to offline in life-cycle, and it can also enhance process control, collaborative research and service ability of ultra-precision optical elements.
Li, Guiting; Jiang, Junqi; Chen, Jie; Zou, Yunding; Zhang, Xincai
2006-01-01
By the method of OECD filter paper contact, this paper studied the effects of applied rare earth elements on soil fauna community structure and their ecological toxicity to Holotrichia parallela in bean field. The results showed that there were no significant differences between the treatments and the control in soil fauna species, quantity of main species, and diversity index. Urgent and chronic toxic test showed that the differences between the treatments and the control were not significant. It was suggested that within the range of test dosages, rare earth elements had little ecological toxicity to Holotrichia parallela, and did not change the soil fauna community structure.
The Pioneer Projects - Economical exploration of the solar system
NASA Technical Reports Server (NTRS)
Spahr, J. R.; Hall, C. F.
1975-01-01
The interplanetary Pioneer missions are reviewed in terms of management implications and cost control. The responsibilities, organizational structure, and management practices of the Pioneer Projects are presented. The lines of authority and areas of responsibility of the principal organizational elements supporting the Pioneer missions are identified, and the methods employed for maintaining effective and timely interactions among these elements are indicated. The technical and administrative functions of various organizational elements of the project are described. The management and control of activities prior to and during the hardware procurement phase are described to indicate the basis for obtaining visibility of the technical progress, utilization of resources, and cost performance of the contractors and other institutions supporting the Pioneer projects.
NASA Technical Reports Server (NTRS)
Bundick, W. T.
1985-01-01
The application of the failure detection filter to the detection and identification of aircraft control element failures was evaluated in a linear digital simulation of the longitudinal dynamics of a B-737 Aircraft. Simulation results show that with a simple correlator and threshold detector used to process the filter residuals, the failure detection performance is seriously degraded by the effects of turbulence.
NASA Technical Reports Server (NTRS)
Bundick, W. T.
1985-01-01
The application of the Generalized Likelihood Ratio technique to the detection and identification of aircraft control element failures has been evaluated in a linear digital simulation of the longitudinal dynamics of a B-737 aircraft. Simulation results show that the technique has potential but that the effects of wind turbulence and Kalman filter model errors are problems which must be overcome.
Pfleger, Brian; Mendez-Perez, Daniel
2013-11-05
Disclosed are systems and methods for coupling translation of a target gene to a detectable response gene. A version of the invention includes a translation-coupling cassette. The translation-coupling cassette includes a target gene, a response gene, a response-gene translation control element, and a secondary structure-forming sequence that reversibly forms a secondary structure masking the response-gene translation control element. Masking of the response-gene translation control element inhibits translation of the response gene. Full translation of the target gene results in unfolding of the secondary structure and consequent translation of the response gene. Translation of the target gene is determined by detecting presence of the response-gene protein product. The invention further includes RNA transcripts of the translation-coupling cassettes, vectors comprising the translation-coupling cassettes, hosts comprising the translation-coupling cassettes, methods of using the translation-coupling cassettes, and gene products produced with the translation-coupling cassettes.
Active muscle response using feedback control of a finite element human arm model.
Östh, Jonas; Brolin, Karin; Happee, Riender
2012-01-01
Mathematical human body models (HBMs) are important research tools that are used to study the human response in car crash situations. Development of automotive safety systems requires the implementation of active muscle response in HBM, as novel safety systems also interact with vehicle occupants in the pre-crash phase. In this study, active muscle response was implemented using feedback control of a nonlinear muscle model in the right upper extremity of a finite element (FE) HBM. Hill-type line muscle elements were added, and the active and passive properties were assessed. Volunteer tests with low impact loading resulting in elbow flexion motions were performed. Simulations of posture maintenance in a gravity field and the volunteer tests were successfully conducted. It was concluded that feedback control of a nonlinear musculoskeletal model can be used to obtain posture maintenance and human-like reflexive responses in an FE HBM.
Power system characteristics for more electric aircraft
NASA Technical Reports Server (NTRS)
Hansen, Irving G.
1993-01-01
It should not be suprising that more electric aircraft must meet significantly more difficult electrical power system requirements than were considereed when today's power distribution systems were being developed. Electric power, no longer a secondary system, will become a critical element of the primary control system. Functional reliability requiirements will be extremely stringent and can only be met by controlling element redundancy within a distributed power system. Existing electrical systems were not developed to have both the power system and the control/sensing elements distributed and yet meet the requirements of lighting tolerance and high intensity radio frequency (HIRF). In addition, the operation of electric actuators involves high transient loading and reverse energy flows. Such phenomena were also not anticipated when power quality was specified for either 270 vdc or 400 Hertz ac power systems. This paper will expand upon the issues and discuss some of the technologies involved in their resolution.
Adhesion, friction, and wear of binary alloys in contact with single-crystal silicon carbide
NASA Technical Reports Server (NTRS)
Miyoshi, K.; Buckley, D. H.
1980-01-01
Sliding friction experiments, conducted with various iron base alloys (alloying elements are Ti, Cr, Mn, Ni, Rh and W) in contact with a single crystal silicon carbide /0001/ surface in vacuum are discussed. Results indicate atomic size misfit and concentration of alloying elements play a dominant role in controlling adhesion, friction, and wear properties of iron-base binary alloys. The controlling mechanism of the alloy properties is as an intrinsic effect involving the resistance to shear fracture of cohesive bonding in the alloy. The coefficient of friction generally increases with an increase in solute concentration. The coefficient of friction increases as the solute-to-iron atomic radius ratio increases or decreases from unity. Alloys having higher solute concentration produce more transfer to silicon carbide than do alloys having low solute concentrations. The chemical activity of the alloying element is also an important parameter in controlling adhesion and friction of alloys.
Method and device for predicting wavelength dependent radiation influences in thermal systems
Kee, Robert J.; Ting, Aili
1996-01-01
A method and apparatus for predicting the spectral (wavelength-dependent) radiation transport in thermal systems including interaction by the radiation with partially transmitting medium. The predicted model of the thermal system is used to design and control the thermal system. The predictions are well suited to be implemented in design and control of rapid thermal processing (RTP) reactors. The method involves generating a spectral thermal radiation transport model of an RTP reactor. The method also involves specifying a desired wafer time dependent temperature profile. The method further involves calculating an inverse of the generated model using the desired wafer time dependent temperature to determine heating element parameters required to produce the desired profile. The method also involves controlling the heating elements of the RTP reactor in accordance with the heating element parameters to heat the wafer in accordance with the desired profile.
Pfleger, Brian; Mendez-Perez, Daniel
2015-05-19
Disclosed are systems and methods for coupling translation of a target gene to a detectable response gene. A version of the invention includes a translation-coupling cassette. The translation-coupling cassette includes a target gene, a response gene, a response-gene translation control element, and a secondary structure-forming sequence that reversibly forms a secondary structure masking the response-gene translation control element. Masking of the response-gene translation control element inhibits translation of the response gene. Full translation of the target gene results in unfolding of the secondary structure and consequent translation of the response gene. Translation of the target gene is determined by detecting presence of the response-gene protein product. The invention further includes RNA transcripts of the translation-coupling cassettes, vectors comprising the translation-coupling cassettes, hosts comprising the translation-coupling cassettes, methods of using the translation-coupling cassettes, and gene products produced with the translation-coupling cassettes.
Lashkari, A; Khalafi, H; Kazeminejad, H
2013-05-01
In this work, kinetic parameters of Tehran research reactor (TRR) mixed cores have been calculated. The mixed core configurations are made by replacement of the low enriched uranium control fuel elements with highly enriched uranium control fuel elements in the reference core. The MTR_PC package, a nuclear reactor analysis tool, is used to perform the analysis. Simulations were carried out to compute effective delayed neutron fraction and prompt neutron lifetime. Calculation of kinetic parameters is necessary for reactivity and power excursion transient analysis. The results of this research show that effective delayed neutron fraction decreases and prompt neutron lifetime increases with the fuels burn-up. Also, by increasing the number of highly enriched uranium control fuel elements in the reference core, the prompt neutron lifetime increases, but effective delayed neutron fraction does not show any considerable change.
Effective delayed neutron fraction and prompt neutron lifetime of Tehran research reactor mixed-core
Lashkari, A.; Khalafi, H.; Kazeminejad, H.
2013-01-01
In this work, kinetic parameters of Tehran research reactor (TRR) mixed cores have been calculated. The mixed core configurations are made by replacement of the low enriched uranium control fuel elements with highly enriched uranium control fuel elements in the reference core. The MTR_PC package, a nuclear reactor analysis tool, is used to perform the analysis. Simulations were carried out to compute effective delayed neutron fraction and prompt neutron lifetime. Calculation of kinetic parameters is necessary for reactivity and power excursion transient analysis. The results of this research show that effective delayed neutron fraction decreases and prompt neutron lifetime increases with the fuels burn-up. Also, by increasing the number of highly enriched uranium control fuel elements in the reference core, the prompt neutron lifetime increases, but effective delayed neutron fraction does not show any considerable change. PMID:24976672
Saravanan, P; Krishnakumar, S; Silva, Judith D; Pradhap, D; Vidyasakar, A; Radhakrishnan, K; Godson, Prince S; Arumugam, K; Magesh, N S
2018-03-01
Thirty three surface sediments were collected for the present study to assess the elemental concentration and its associated ecological risk in the reef associated surface sediments, Appa Island, Gulf of Mannar Biosphere Reserve, South east coast of India. The distribution of calcium carbonate in the reef sediments is controlled by coral debris and shell fragments whereas the Organic matter (OM) content are chiefly derived from mangroves and sea grasses. The circulation of trace elements and Fe, Mn are controlled by the fluvial process and re-suspended sediments. The concentration of Pb was primarily controlled by migration of pollutants through long shore sediment transport process. The main source of Pb in the study area is from coal incinerating power plants and coal handling operations from harbors. Copyright © 2018 Elsevier Ltd. All rights reserved.
NASA Technical Reports Server (NTRS)
Bickford, R. L.; Collamore, F. N.; Gage, M. L.; Morgan, D. B.; Thomas, E. R.
1992-01-01
The objectives of this task were to: (1) estimate the technology readiness of an integrated control and health monitoring (ICHM) system for the Aerojet 7500 lbF Orbit Transfer Vehicle engine preliminary design assuming space based operations; and (2) estimate the remaining cost to advance this technology to a NASA defined 'readiness level 6' by 1996 wherein the technology has been demonstrated with a system validation model in a simulated environment. The work was accomplished through the conduct of four subtasks. In subtask 1 the minimally required functions for the control and monitoring system was specified. The elements required to perform these functions were specified in Subtask 2. In Subtask 3, the technology readiness level of each element was assessed. Finally, in Subtask 4, the development cost and schedule requirements were estimated for bringing each element to 'readiness level 6'.
NASA Technical Reports Server (NTRS)
Silcox, Richard J. (Inventor); Fuller, Chris R. (Inventor); Gibbs, Gary P. (Inventor)
1992-01-01
Arrays of actuators are affixed to structural elements to impede the transmission of vibrational energy. A single pair is used to provide control of bending and extensional waves and two pairs are used to control torsional motion. The arrays are applied to a wide variety of structural elements such as a beam structure that is part of a larger framework that may or may not support a rigid or non-rigid skin. Electrical excitation is applied to the actuators that generate forces on the structure. These electrical inputs may be adjusted in their amplitude and phase by a controller in communication with appropriate vibrational wave sensors to impede the flow of vibrational power in all of the above mentioned wave forms beyond the actuator location. Additional sensor elements can be used to monitor the performance and adjust the electrical inputs to maximize the attenuation of vibrational energy.
NASA Astrophysics Data System (ADS)
Mahan, B. M.; Siebert, J.; Blanchard, I.; Badro, J.; Sossi, P.; Moynier, F.
2017-12-01
Volatile and moderately volatile elements display different volatilities and siderophilities, as well as varying sensitivity to thermodynamic controls (X, P, T, fO2) during metal-silicate differentiation. The experimental determination of the metal-silicate partitioning of these elements permits us to evaluate processes controlling the distribution of these elements in Earth. In this work, we have combined metal-silicate partitioning data and results for S, Sn, Zn and Cu, and input these characterizations into Earth formation models. Model parameters such as source material, timing of volatile delivery, fO2 path, and degree of impactor equilibration were varied to encompass an array of possible formation scenarios. These models were then assessed to discern plausible sets of conditions that can produce current observed element-to-element ratios (e.g. S/Zn) in the Earth's present-day mantle, while also satisfying current estimates on the S content of the core, at no more than 2 wt%. The results of our models indicate two modes of accretion that can maintain chondritic element-to-element ratios for the bulk Earth and can arrive at present-day mantle abundances of these elements. The first mode requires the late addition of Earth's entire inventory of these elements (assuming a CI-chondritic composition) and late-stage accretion that is marked by partial equilibration of large impactors. The second, possibly more intuitive mode, requires that Earth accreted - at least initially - from volatile poor material preferentially depleted in S relative to Sn, Zn, and Cu. From a chemical standpoint, this source material is most similar to type I chondrule rich (and S poor) materials (Hewins and Herzberg, 1996; Mahan et al., 2017; Amsellem et al., 2017), such as the metal-bearing carbonaceous chondrites.
NASA Astrophysics Data System (ADS)
Kim, Gi-Woo; Wang, K. W.
2008-03-01
In recent years, researchers have investigated the feasibility of utilizing piezoelectric-hydraulic pump based actuation systems for automotive transmission controls. This new concept could eventually reduce the complexity, weight, and fuel consumption of the current transmissions. In this research, we focus on how to utilize this new approach on the shift control of automatic transmissions (AT), which generally requires pressure profiling for friction elements during the operation. To illustrate the concept, we will consider the 1--> 2 up shift control using band brake friction elements. In order to perform the actuation force tracking for AT shift control, nonlinear force feedback control laws are designed based on the sliding mode theory for the given nonlinear system. This paper will describe the modeling of the band brake actuation system, the design of the nonlinear force feedback controller, and simulation and experimental results for demonstration of the new concept.
Nakahata, Yasukazu; Yoshida, Mayumi; Takano, Atsuko; Soma, Haruhiko; Yamamoto, Takuro; Yasuda, Akio; Nakatsu, Toru; Takumi, Toru
2008-01-01
Background The circadian expression of the mammalian clock genes is based on transcriptional feedback loops. Two basic helix-loop-helix (bHLH) PAS (for Period-Arnt-Sim) domain-containing transcriptional activators, CLOCK and BMAL1, are known to regulate gene expression by interacting with a promoter element termed the E-box (CACGTG). The non-canonical E-boxes or E-box-like sequences have also been reported to be necessary for circadian oscillation. Results We report a new cis-element required for cell-autonomous circadian transcription of clock genes. This new element consists of a canonical E-box or a non-canonical E-box and an E-box-like sequence in tandem with the latter with a short interval, 6 base pairs, between them. We demonstrate that both E-box or E-box-like sequences are needed to generate cell-autonomous oscillation. We also verify that the spacing nucleotides with constant length between these 2 E-elements are crucial for robust oscillation. Furthermore, by in silico analysis we conclude that several clock and clock-controlled genes possess a direct repeat of the E-box-like elements in their promoter region. Conclusion We propose a novel possible mechanism regulated by double E-box-like elements, not to a single E-box, for circadian transcriptional oscillation. The direct repeat of the E-box-like elements identified in this study is the minimal required element for the generation of cell-autonomous transcriptional oscillation of clock and clock-controlled genes. PMID:18177499
Hot wire needle probe for thermal conductivity detection
Condie, Keith Glenn; Rempe, Joy Lynn; Knudson, Darrell lee; Daw, Joshua Earl; Wilkins, Steven Curtis; Fox, Brandon S.; Heng, Ban
2015-11-10
An apparatus comprising a needle probe comprising a sheath, a heating element, a temperature sensor, and electrical insulation that allows thermal conductivity to be measured in extreme environments, such as in high-temperature irradiation testing. The heating element is contained within the sheath and is electrically conductive. In an embodiment, the heating element is a wire capable of being joule heated when an electrical current is applied. The temperature sensor is contained within the sheath, electrically insulated from the heating element and the sheath. The electrical insulation electrically insulates the sheath, heating element and temperature sensor. The electrical insulation fills the sheath having electrical resistance capable of preventing electrical conduction between the sheath, heating element, and temperature sensor. The control system is connected to the heating element and the temperature sensor.
Method for producing nanocrystalline multicomponent and multiphase materials
Eastman, J.A.; Rittner, M.N.; Youngdahl, C.J.; Weertman, J.R.
1998-03-17
A process for producing multi-component and multiphase nanophase materials is provided wherein a plurality of elements are vaporized in a controlled atmosphere, so as to facilitate thorough mixing, and then condensing and consolidating the elements. The invention also provides for a multicomponent and multiphase nanocrystalline material of specified elemental and phase composition having component grain sizes of between approximately 1 nm and 100 nm. This material is a single element in combination with a binary compound. In more specific embodiments, the single element in this material can be a transition metal element, a non-transition metal element, a semiconductor, or a semi-metal, and the binary compound in this material can be an intermetallic, an oxide, a nitride, a hydride, a chloride, or other compound. 6 figs.
Organization of cis-acting regulatory elements in osmotic- and cold-stress-responsive promoters.
Yamaguchi-Shinozaki, Kazuko; Shinozaki, Kazuo
2005-02-01
cis-Acting regulatory elements are important molecular switches involved in the transcriptional regulation of a dynamic network of gene activities controlling various biological processes, including abiotic stress responses, hormone responses and developmental processes. In particular, understanding regulatory gene networks in stress response cascades depends on successful functional analyses of cis-acting elements. The ever-improving accuracy of transcriptome expression profiling has led to the identification of various combinations of cis-acting elements in the promoter regions of stress-inducible genes involved in stress and hormone responses. Here we discuss major cis-acting elements, such as the ABA-responsive element (ABRE) and the dehydration-responsive element/C-repeat (DRE/CRT), that are a vital part of ABA-dependent and ABA-independent gene expression in osmotic and cold stress responses.
Briat, Jean-François; Rouached, Hatem; Tissot, Nicolas; Gaymard, Frédéric; Dubos, Christian
2015-01-01
Phosphate and sulfate are essential macro-elements for plant growth and development, and deficiencies in these mineral elements alter many metabolic functions. Nutritional constraints are not restricted to macro-elements. Essential metals such as zinc and iron have their homeostasis strictly genetically controlled, and deficiency or excess of these micro-elements can generate major physiological disorders, also impacting plant growth and development. Phosphate and sulfate on one hand, and zinc and iron on the other hand, are known to interact. These interactions have been partly described at the molecular and physiological levels, and are reviewed here. Furthermore the two macro-elements phosphate and sulfate not only interact between themselves but also influence zinc and iron nutrition. These intricated nutritional cross-talks are presented. The responses of plants to phosphorus, sulfur, zinc, or iron deficiencies have been widely studied considering each element separately, and some molecular actors of these regulations have been characterized in detail. Although some scarce reports have started to examine the interaction of these mineral elements two by two, a more complex analysis of the interactions and cross-talks between the signaling pathways integrating the homeostasis of these various elements is still lacking. However, a MYB-like transcription factor, PHOSPHATE STARVATION RESPONSE 1, emerges as a common regulator of phosphate, sulfate, zinc, and iron homeostasis, and its role as a potential general integrator for the control of mineral nutrition is discussed. PMID:25972885
A STUDY ON THE HIERARCHY OF MANAGEMENT ELEMENTS
NASA Astrophysics Data System (ADS)
Suzuki, Nobuyuki; Watanabe, Tadashi
Compared to the late 20th century, the Japanese construction industry has drastically changed its business methodology, outlook and approach in response to global issues and the incredible advances in technology. Such influences, non-exhaustively include the; WTO Government procurement agreement, updating conditions of tendering and contracting, client demands for cost reduction and the rapid penetration of ICT (Information and Communication Technology) into modern society. These days, the significance of controlling Quality, Cost and Time (the so-called QCT) has been recognized as an eternal-triangle by almost all countries, Government organizations and the private sector. However, as the construction industry is exposed to , and influenced by, more and more internal and external dynamic factors, continued reliance on managing and controlling QCT elements on their own is no longer adequate in meeting the growing demands and expectations, and as such control of additional management elements is now essential to avoid problems, or minimize their potential impacts should they occur. This paper utilizes the results of a survey carried out amongst construction managers and consultants in Japan and overseas to develop a spatial network that defines the interaction of management factors as a weighted graphical model. The calculated closeness centrality index of the developed management network model is adopted to identify the initialelement hierarchy, which is then further analyzed using the minimum distance of independent relationships of management elements (Warshall-Floyd algorism methodology), to identify the optimum potential hierarchy for effective construction management. A key result of the analysis is the significance of "Human Resource" in the construction industry management element hierarchy alongside the traditional QCT elements.
Schnapp, A; Clos, J; Hädelt, W; Schreck, R; Cvekl, A; Grummt, I
1990-03-25
The murine ribosomal gene promoter contains two cis-acting control elements which operate in concert to promote efficient and accurate transcription initiation by RNA polymerase I. The start site proximal core element which is indispensable for promoter recognition by RNA polymerase I (pol I) encompasses sequences from position -39 to -1. An upstream control element (UCE) which is located between nucleotides -142 and -112 stimulates the efficiency of transcription initiation both in vivo and in vitro. Here we report the isolation and functional characterization of a specific rDNA binding protein, the transcription initiation factor TIF-IB, which specifically interacts with the core region of the mouse ribosomal RNA gene promoter. Highly purified TIF-IB complements transcriptional activity in the presence of two other essential initiation factors TIF-IA and TIF-IC. We demonstrate that the binding efficiency of purified TIF-IB to the core promoter is strongly enhanced by the presence in cis of the UCE. This positive effect of upstream sequences on TIF-IB binding is observed throughout the purification procedure suggesting that the synergistic action of the two distant promoter elements is not mediated by a protein different from TIF-IB. Increasing the distance between both control elements still facilitates stable factor binding but eliminates transcriptional activation. The results demonstrate that TIF-IB binding to the rDNA promoter is an essential early step in the assembly of a functional transcription initiation complex. The subsequent interaction of TIF-IB with other auxiliary transcription initiation factors, however, requires the correct spacing between the UCE and the core promoter element.
Advanced hybrid particulate collector and method of operation
Miller, Stanley J [Grand Forks, ND
2003-04-08
A device and method for controlling particulate air pollutants of the present invention combines filtration and electrostatic collection devices. The invention includes a chamber housing a plurality of rows of filter elements. Between the rows of filter elements are rows of high voltage discharge electrodes. Between the rows of discharge electrodes and the rows of filter elements are grounded perforated plates for creating electrostatic precipitation zones.
Space Vehicle Guidance, Navigation, Control, and Estimation Operations Technologies
2018-03-29
angular position around the ellipse, and the out-of-place amplitude and angular position. These elements are explicitly relatable to the six rectangular...quasi) second order relative orbital elements are explored. One theory uses the expanded solution form and introduces several instantaneous ellipses...In each case, the theory quantifies distortion of the first order relative orbital elements when including second order effects. The new variables are
ERIC Educational Resources Information Center
Munley, Maripat
2002-01-01
Explores whether children with AD/HD respond differently to a specific art directive. Using the Formal Elements Art Therapy Scale to evaluate the drawings, results indicate three elements that would most accurately predict the artists into the AD/HD group: color prominence, details of objects and environments, and line quality. (Contains 29…
40 CFR 86.1803-01 - Definitions.
Code of Federal Regulations, 2014 CFR
2014-07-01
.... Auxiliary Emission Control Device (AECD) means any element of design which senses temperature, vehicle speed.... Critical emission-related components are those components which are designed primarily for emission control... control system is a unique group of emission control devices, auxiliary emission control devices, engine...
Systems and methods for deactivating a matrix converter
Ransom, Ray M.
2013-04-02
Systems and methods are provided for deactivating a matrix conversion module. An electrical system comprises an alternating current (AC) interface, a matrix conversion module coupled to the AC interface, an inductive element coupled between the AC interface and the matrix conversion module, and a control module. The control module is coupled to the matrix conversion module, and in response to a shutdown condition, the control module is configured to operate the matrix conversion module to deactivate the first conversion module when a magnitude of a current through the inductive element is less than a threshold value.
Automated Power Systems Management (APSM)
NASA Technical Reports Server (NTRS)
Bridgeforth, A. O.
1981-01-01
A breadboard power system incorporating autonomous functions of monitoring, fault detection and recovery, command and control was developed, tested and evaluated to demonstrate technology feasibility. Autonomous functions including switching of redundant power processing elements, individual load fault removal, and battery charge/discharge control were implemented by means of a distributed microcomputer system within the power subsystem. Three local microcomputers provide the monitoring, control and command function interfaces between the central power subsystem microcomputer and the power sources, power processing and power distribution elements. The central microcomputer is the interface between the local microcomputers and the spacecraft central computer or ground test equipment.
Trace elements in sera of patients with hepatitis B: Determination and analysis
NASA Astrophysics Data System (ADS)
Saod, Wahran M.; Darwish, Nadiya T.; Zaidan, Tahseen A.; Alfalujie, Abdul Wahab A.
2018-04-01
Chronic Hepatitis B (HBV) is the leading cause of morbidity and mortality worldwide with about 248 million people having HBV infection. Trace elements e.g. copper (Cu), zinc (Zn), selenium (Se) and iron (Fe) are constituent components of many metal proteins and metalloenzymes in human sera. Therefore, the ratios of these trace elements in human sera are often stated to be a good marker for diagnosing various diseases including HBV. The aims of this study are: to compare the level of trace elements in sera of patients infected with HBV and healthy participants, and to evaluate the efficiency of analytical techniques (e.g. Inductively Coupled Plasma-Mass spectrometry (ICP-MS), Atomic Absorption Spectroscopy (hydride generation) (AAS) and Graphite Furnace Atomic Absorption Spectroscopy (GFAAS) that are currently used to detect Fe and Se elements in Patients' human sera. The findings of this study show that the concentration range of copper element between (132.80±28.64 µg/dl) to (105.66±23.20 µg/dl) was significantly higher in HBV infected patients as compared to those in healthy controls (91.27±9.20 µg/dl). Iron concentration range between (206.64±61.60 µg/l) to (170.00±36.71 µg/l) was significantly higher in HBV infected patients as compared to those in healthy controls (158.00±15.13 µg/l). However, patients with HBV had significantly lower serum concentrations of zinc with a concentration range between (111.64±20.90 µg/dl) to (99.25±24.06 µg/dl) as compared to those in healthy controls (113.44±16.38 µg/dl). While selenium concentration range between (64.39±7.39 µg/l) to (51.10±4.96 µg/l) was significantly lower in HBV infected patients as compared to those in healthy controls (67.68±7.60) (μg/l). Moreover, the results of this study suggest that (AAS) technique was the most accurate method to measure the concentration of selenium element, while (UV and ICP-MS) analytical techniques have the same efficiency in measuring the iron concentration.
Use of an Oral Elemental Diet in Infants with Severe Intractable Diarrhea
ERIC Educational Resources Information Center
Sherman, Joseph O.; And Others
1975-01-01
Evaluated was the use of an oral elemental diet consisting of crystalline amino acids, glucose, electrolytes, and vitamins to control severe intractable diarrhea in 27 infants (1-day to 9-months of age). (DB)
Code of Federal Regulations, 2010 CFR
2010-07-01
... system of records maintained by DCAA organizational elements and to make that information available to... requires that DCAA organizational elements: (1) Collect, maintain, use, and disseminate personal... instrumentality of any governmental jurisdiction within or under control of the United States conducting law...
Connectivity has become a major focus of hydrological and ecological studies. Connectivity influences fluxes between landscape elements, while isolation reduces flows between elements. Thus connectivity can be an important characteristic controlling ecosystem services. Hydrolo...
Methanogenesis from wastewater stimulated by addition of elemental manganese
Qiao, Sen; Tian, Tian; Qi, Benyu; Zhou, Jiti
2015-01-01
This study presents a novel procedure for accelerating methanogenesis from wastewater by adding elemental manganese into the anaerobic digestion system. The results indicated that elemental manganese effectively enhanced both the methane yield and the production rate. Compared to the control test without elemental manganese, the total methane yield and production rate with 4 g/L manganese addition increased 3.4-fold (from 0.89 ± 0.03 to 2.99 ± 0.37 M/gVSS within 120 h) and 4.4-fold (from 6.2 ± 0.1 to 27.2 ± 2.2 mM/gVSS/h), respectively. Besides, more acetate consumption and less propionate generation were observed during the methanogenesis with manganese. Further studies demonstrated that the elemental manganese served as electron donors for the methanogenesis from carbon dioxide, and the final proportion of methane in the total generated gas with 4 g/L manganese addition reached 96.9%, which was 2.1-fold than that of the control (46.6%). PMID:26244609
Awodele, Olufunsho; Akinyede, Akin; Babawale, Omotola Opeyemi; Coker, Herbert A Babatunde; Akintonwa, Alade
2013-06-01
Adverse effects attributed to exposure to paints are currently a concern because of the continued widespread use of paint containing trace elements. Thus, occupational survey amongst painters in Lagos and determination of trace elements and oxidative stress parameters were carried out. Descriptive cross-sectional survey was done using a standardized questionnaire to obtain job safety-related information. Forty-eight percent of the painters were aware of hazards associated with painting and 52 % of these workers were aware of the necessary precautionary measures during painting. There were no significant differences (p ≥ 0.05) between the levels of trace elements in the blood of painters and the control subjects. However, there was a significance increase (p ≤ 0.0001) in the level of malondialdehyde and a decrease (p ≤ 0.001) in the levels of reduced glutathione, superoxide dismutase, and catalase of the painters compared to the control. An increase in oxidative stress parameters may not only be due to trace element concentrations, but also the painters' exposure to some petrochemical solvents during mixing of paints.
Vital effects in coral skeletal composition display strict three-dimensional control
Meibom, A.; Yurimoto, H.; Cuif, J.-P.; Domart-Coulon, I.; Houlbreque, F.; Constantz, B.; Dauphin, Y.; Tambutte, E.; Tambutte, S.; Allemand, D.; Wooden, J.; Dunbar, R.
2006-01-01
Biological control over coral skeletal composition is poorly understood but critically important to paleoenvironmental reconstructions. We present microanalytical measurements of trace-element abundances as well as oxygen and carbon isotopic compositions of individual skeletal components in the zooxanthellate coral Colpophyllia sp. Our data show that centers of calcification (COC) have higher trace element concentrations and distinctly lighter isotopic compositions than the fibrous components of the skeleton. These observations necessitate that COC and the fibrous skeleton are precipitated by different mechanisms, which are controlled by specialized domains of the calicoblastic cell-layer. Biological processes control the composition of the skeleton even at the ultra-structure level. Copyright 2006 by the American Geophysical Union.
Methods of Statistical Control for Groundwater Quality Indicators
NASA Astrophysics Data System (ADS)
Yankovich, E.; Nevidimova, O.; Yankovich, K.
2016-06-01
The article describes the results of conducted groundwater quality control. Controlled quality indicators included the following microelements - barium, manganese, iron, mercury, iodine, chromium, strontium, etc. Quality control charts - X-bar chart and R chart - were built. For the upper and the lower threshold limits, maximum permissible concentration of components in water and the lower limit of their biologically significant concentration, respectively, were selected. The charts analysis has shown that the levels of microelements content in water at the area of study are stable. Most elements in the underground water are contained in concentrations, significant for human organisms consuming the water. For example, such elements as Ba, Mn, Fe have concentrations that exceed maximum permissible levels for drinking water.
Oti, Martin; Dutilh, Bas E.; Alonso, M. Eva; de la Calle-Mustienes, Elisa; Smeenk, Leonie; Rinne, Tuula; Parsaulian, Lilian; Bolat, Emine; Jurgelenaite, Rasa; Huynen, Martijn A.; Hoischen, Alexander; Veltman, Joris A.; Brunner, Han G.; Roscioli, Tony; Oates, Emily; Wilson, Meredith; Manzanares, Miguel; Gómez-Skarmeta, José Luis; Stunnenberg, Hendrik G.; Lohrum, Marion; van Bokhoven, Hans; Zhou, Huiqing
2010-01-01
Heterozygous mutations in p63 are associated with split hand/foot malformations (SHFM), orofacial clefting, and ectodermal abnormalities. Elucidation of the p63 gene network that includes target genes and regulatory elements may reveal new genes for other malformation disorders. We performed genome-wide DNA–binding profiling by chromatin immunoprecipitation (ChIP), followed by deep sequencing (ChIP–seq) in primary human keratinocytes, and identified potential target genes and regulatory elements controlled by p63. We show that p63 binds to an enhancer element in the SHFM1 locus on chromosome 7q and that this element controls expression of DLX6 and possibly DLX5, both of which are important for limb development. A unique micro-deletion including this enhancer element, but not the DLX5/DLX6 genes, was identified in a patient with SHFM. Our study strongly indicates disruption of a non-coding cis-regulatory element located more than 250 kb from the DLX5/DLX6 genes as a novel disease mechanism in SHFM1. These data provide a proof-of-concept that the catalogue of p63 binding sites identified in this study may be of relevance to the studies of SHFM and other congenital malformations that resemble the p63-associated phenotypes. PMID:20808887
The impact of dissociation on transposon-mediated disease control strategies.
Marshall, John M
2008-03-01
Vector-borne diseases such as malaria and dengue fever continue to be a major health concern through much of the world. The emergence of chloroquine-resistant strains of malaria and insecticide-resistant mosquitoes emphasize the need for novel methods of disease control. Recently, there has been much interest in the use of transposable elements to drive resistance genes into vector populations as a means of disease control. One concern that must be addressed before a release is performed is the potential loss of linkage between a transposable element and a resistance gene. Transposable elements such as P and hobo have been shown to produce internal deletion derivatives at a significant rate, and there is concern that a similar process could lead to loss of the resistance gene from the drive system following a transgenic release. Additionally, transposable elements such as Himar1 have been shown to transpose significantly more frequently when free of exogenous DNA. Here, we show that any transposon-mediated gene drive strategy must have an exceptionally low rate of dissociation if it is to be effective. Additionally, the resistance gene must confer a large selective advantage to the vector to surmount the effects of a moderate dissociation rate and transpositional handicap.
Bayesian nonparametric adaptive control using Gaussian processes.
Chowdhary, Girish; Kingravi, Hassan A; How, Jonathan P; Vela, Patricio A
2015-03-01
Most current model reference adaptive control (MRAC) methods rely on parametric adaptive elements, in which the number of parameters of the adaptive element are fixed a priori, often through expert judgment. An example of such an adaptive element is radial basis function networks (RBFNs), with RBF centers preallocated based on the expected operating domain. If the system operates outside of the expected operating domain, this adaptive element can become noneffective in capturing and canceling the uncertainty, thus rendering the adaptive controller only semiglobal in nature. This paper investigates a Gaussian process-based Bayesian MRAC architecture (GP-MRAC), which leverages the power and flexibility of GP Bayesian nonparametric models of uncertainty. The GP-MRAC does not require the centers to be preallocated, can inherently handle measurement noise, and enables MRAC to handle a broader set of uncertainties, including those that are defined as distributions over functions. We use stochastic stability arguments to show that GP-MRAC guarantees good closed-loop performance with no prior domain knowledge of the uncertainty. Online implementable GP inference methods are compared in numerical simulations against RBFN-MRAC with preallocated centers and are shown to provide better tracking and improved long-term learning.
Trace element profiles of the sea anemone Anemonia viridis living nearby a natural CO2 vent
Borell, Esther M.; Fine, Maoz; Shaked, Yeala
2014-01-01
Ocean acidification (OA) is not an isolated threat, but acts in concert with other impacts on ecosystems and species. Coastal marine invertebrates will have to face the synergistic interactions of OA with other global and local stressors. One local factor, common in coastal environments, is trace element contamination. CO2 vent sites are extensively studied in the context of OA and are often considered analogous to the oceans in the next few decades. The CO2 vent found at Levante Bay (Vulcano, NE Sicily, Italy) also releases high concentrations of trace elements to its surrounding seawater, and is therefore a unique site to examine the effects of long-term exposure of nearby organisms to high pCO2 and trace element enrichment in situ. The sea anemone Anemonia viridis is prevalent next to the Vulcano vent and does not show signs of trace element poisoning/stress. The aim of our study was to compare A. viridis trace element profiles and compartmentalization between high pCO2 and control environments. Rather than examining whole anemone tissue, we analyzed two different body compartments—the pedal disc and the tentacles, and also examined the distribution of trace elements in the tentacles between the animal and the symbiotic algae. We found dramatic changes in trace element tissue concentrations between the high pCO2/high trace element and control sites, with strong accumulation of iron, lead, copper and cobalt, but decreased concentrations of cadmium, zinc and arsenic proximate to the vent. The pedal disc contained substantially more trace elements than the anemone’s tentacles, suggesting the pedal disc may serve as a detoxification/storage site for excess trace elements. Within the tentacles, the various trace elements displayed different partitioning patterns between animal tissue and algal symbionts. At both sites iron was found primarily in the algae, whereas cadmium, zinc and arsenic were primarily found in the animal tissue. Our data suggests that A. viridis regulates its internal trace element concentrations by compartmentalization and excretion and that these features contribute to its resilience and potential success at the trace element-rich high pCO2 vent. PMID:25250210
Overview of NASA's Thermal Control System Development for Exploration Project
NASA Technical Reports Server (NTRS)
Stephan, Ryan A.
2010-01-01
NASA's Constellation Program includes the Orion, Altair, and Lunar Surface Systems project offices. The first two elements, Orion and Altair, are manned space vehicles while the third element is broader and includes several sub-elements including Rovers and a Lunar Habitat. The upcoming planned missions involving these systems and vehicles include several risks and design challenges. Due to the unique thermal environment, many of these risks and challenges are associated with the vehicles' thermal control system. NASA's Exploration Systems Mission Directorate (ESMD) includes the Exploration Technology Development Program (ETDP). ETDP consists of several technology development projects. The project chartered with mitigating the aforementioned risks and design challenges is the Thermal Control System Development for Exploration Project. The risks and design challenges are addressed through a rigorous technology development process that culminates with an integrated thermal control system test. The resulting hardware typically has a Technology Readiness Level (TRL) of six. This paper summarizes the development efforts being performed by the technology development project. The development efforts involve heat acquisition and heat rejection hardware including radiators, heat exchangers, and evaporators. The project has also been developing advanced phase change material heat sinks and performing assessments for thermal control system fluids.
Thermal breeder fuel enrichment zoning
Capossela, Harry J.; Dwyer, Joseph R.; Luce, Robert G.; McCoy, Daniel F.; Merriman, Floyd C.
1992-01-01
A method and apparatus for improving the performance of a thermal breeder reactor having regions of higher than average moderator concentration are disclosed. The fuel modules of the reactor core contain at least two different types of fuel elements, a high enrichment fuel element and a low enrichment fuel element. The two types of fuel elements are arranged in the fuel module with the low enrichment fuel elements located between the high moderator regions and the high enrichment fuel elements. Preferably, shim rods made of a fertile material are provided in selective regions for controlling the reactivity of the reactor by movement of the shim rods into and out of the reactor core. The moderation of neutrons adjacent the high enrichment fuel elements is preferably minimized as by reducing the spacing of the high enrichment fuel elements and/or using a moderator having a reduced moderating effect.
Image processing occupancy sensor
Brackney, Larry J.
2016-09-27
A system and method of detecting occupants in a building automation system environment using image based occupancy detection and position determinations. In one example, the system includes an image processing occupancy sensor that detects the number and position of occupants within a space that has controllable building elements such as lighting and ventilation diffusers. Based on the position and location of the occupants, the system can finely control the elements to optimize conditions for the occupants, optimize energy usage, among other advantages.
NASA Technical Reports Server (NTRS)
Kumar, A.; Graves, R. A., Jr.; Weilmuenster, K. J.
1980-01-01
A vectorized code, EQUIL, was developed for calculating the equilibrium chemistry of a reacting gas mixture on the Control Data STAR-100 computer. The code provides species mole fractions, mass fractions, and thermodynamic and transport properties of the mixture for given temperature, pressure, and elemental mass fractions. The code is set up for the electrons H, He, C, O, N system of elements. In all, 24 chemical species are included.
Solution of elastic-plastic stress analysis problems by the p-version of the finite element method
NASA Technical Reports Server (NTRS)
Szabo, Barna A.; Actis, Ricardo L.; Holzer, Stefan M.
1993-01-01
The solution of small strain elastic-plastic stress analysis problems by the p-version of the finite element method is discussed. The formulation is based on the deformation theory of plasticity and the displacement method. Practical realization of controlling discretization errors for elastic-plastic problems is the main focus. Numerical examples which include comparisons between the deformation and incremental theories of plasticity under tight control of discretization errors are presented.
Silverstein, M
1994-09-01
Twenty-one Occupational Safety and Health Act (OSHA) standards were identified which contain medical service provisions intended to help in the identification and control of harmful health effects of workplace exposures. The utility and effectiveness of these provisions have not previously been evaluated. All 21 standards were reviewed and assigned numerical scores for each of 24 potential medical program elements. Several of these elements were combined to calculate Quality Control, Screening Utility, and Surveillance Utility scores for each standard. Total scores varied greatly, suggesting a lack of consistency and uniformity which was even more obvious when the actual regulatory language was examined. The mean Quality score was only 26% of potential points. Seventeen of 21 standards received less than half the total possible Quality score. When arrayed on a two by two matrix only two standards scored above 50% for both Screening and Surveillance Utility. It was concluded that the medical service provisions in OSHA standards are lacking in consistency and coherence. Two major shortcomings are the lack of quality control elements and the absence of surveillance features which would permit medical program results to be utilized for prevention activities including the identification and control of workplace hazards. A generic occupational medical surveillance standard could address these current weaknesses. Elements of such a generic standard are proposed.
Effective organizational control: implications for academic medicine.
Wilkes, Michael S; Srinivasan, Malathi; Flamholtz, Eric
2005-11-01
This article provides a framework for understanding the nature, role, functioning, design, and effects of organizational oversight systems. Using a case study with elements recognizable to an academic audience, the authors explore how a dean of a fictitious School of Medicine might use organizational control structures to develop effective solutions to global disarray within the academic medical center. Organizational control systems are intended to help influence the behavior of people as members of a formal organization. They are necessary to motivate people toward organizational goals, to coordinate diverse efforts, and to provide feedback about problems. The authors present a model of control to make this process more visible within organizations. They explore the overlap among academic medical centers and large businesses-for instance, each is a billion-dollar enterprise with complex internal and external demands and multiple audiences. The authors identify and describe how to use the key components of an organization's control system: environment, culture, structure, and core control system. Elements of the core control system are identified, described, and explored. These closely articulating elements include planning, operations, measurement, evaluation, and feedback systems. Use of control portfolios is explored to achieve goal-outcome congruence. Additionally, the authors describe how the components of the control system can be used synergistically by academic leadership to create organizational change, congruent with larger organizational goals. The enterprise of medicine is quickly learning from the enterprise of business. Achieving goal-action congruence will better position academic medicine to meet its multiple missions.
Shafiee, Mohamad N; Mongan, Nigel; Seedhouse, Claire; Chapman, Caroline; Deen, Suha; Abu, Jafaru; Atiomo, William
2017-05-01
Women with polycystic ovary syndrome have a three-fold higher risk of endometrial cancer. Insulin resistance and hyperlipidemia may be pertinent factors in the pathogenesis of both conditions. The aim of this study was to investigate endometrial sterol regulatory element binding protein-1 gene expression in polycystic ovary syndrome and endometrial cancer endometrium, and to correlate endometrial sterol regulatory element binding protein-1 gene expression with serum lipid profiles. A cross-sectional study was performed at Nottingham University Hospital, UK. A total of 102 women (polycystic ovary syndrome, endometrial cancer and controls; 34 participants in each group) were recruited. Clinical and biochemical assessments were performed before endometrial biopsies were obtained from all participants. Taqman real-time polymerase chain reaction for endometrial sterol regulatory element binding protein-1 gene and its systemic protein expression were analyzed. The body mass indices of women with polycystic ovary syndrome (29.28 ± 2.91 kg/m 2 ) and controls (28.58 ± 2.62 kg/m 2 ) were not significantly different. Women with endometrial cancer had a higher mean body mass index (32.22 ± 5.70 kg/m 2 ). Sterol regulatory element binding protein-1 gene expression was significantly increased in polycystic ovary syndrome and endometrial cancer endometrium compared with controls (p < 0.0001). Sterol regulatory element binding protein-1 gene expression was positively correlated with body mass index (r = 0.017, p = 0.921) and waist-hip ratio (r = 0.023, p = 0.544) in polycystic ovary syndrome, but this was not statistically significant. Similarly, statistically insignificant positive correlations were found between endometrial sterol regulatory element binding protein-1 gene expression and body mass index in endometrial cancer (r = 0.643, p = 0.06) and waist-hip ratio (r = 0.096, p = 0.073). Sterol regulatory element binding protein-1 gene expression was significantly positively correlated with triglyceride in both polycystic ovary syndrome and endometrial cancer (p = 0.028 and p = 0.027, respectively). Quantitative serum sterol regulatory element binding protein-1 gene correlated with endometrial gene expression (p < 0.05). Sterol regulatory element binding protein-1 gene expression is significantly increased in the endometrium of women with polycystic ovary syndrome and women with endometrial cancer compared with controls and positively correlates with serum triglyceride in both polycystic ovary syndrome and endometrial cancer. © 2017 Nordic Federation of Societies of Obstetrics and Gynecology.
Adaptive process control using fuzzy logic and genetic algorithms
NASA Technical Reports Server (NTRS)
Karr, C. L.
1993-01-01
Researchers at the U.S. Bureau of Mines have developed adaptive process control systems in which genetic algorithms (GA's) are used to augment fuzzy logic controllers (FLC's). GA's are search algorithms that rapidly locate near-optimum solutions to a wide spectrum of problems by modeling the search procedures of natural genetics. FLC's are rule based systems that efficiently manipulate a problem environment by modeling the 'rule-of-thumb' strategy used in human decision making. Together, GA's and FLC's possess the capabilities necessary to produce powerful, efficient, and robust adaptive control systems. To perform efficiently, such control systems require a control element to manipulate the problem environment, and a learning element to adjust to the changes in the problem environment. Details of an overall adaptive control system are discussed. A specific laboratory acid-base pH system is used to demonstrate the ideas presented.
Quality assessment and control of finite element solutions
NASA Technical Reports Server (NTRS)
Noor, Ahmed K.; Babuska, Ivo
1987-01-01
Status and some recent developments in the techniques for assessing the reliability of finite element solutions are summarized. Discussion focuses on a number of aspects including: the major types of errors in the finite element solutions; techniques used for a posteriori error estimation and the reliability of these estimators; the feedback and adaptive strategies for improving the finite element solutions; and postprocessing approaches used for improving the accuracy of stresses and other important engineering data. Also, future directions for research needed to make error estimation and adaptive movement practical are identified.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Shattan, Michael; Stowe, Ashley; McIntosh, Kathryn
Explore feasibility of portable LIBS and micro-XRF systems as methods of field screening for real debris; Develop a LIBS Capability to rapidly screen beads for production quality control; Complete 3D elemental mapping of surrogate debris to determine uranium and other elemental migration patterns during debris formation
[Influence of shenxu gutong capsule on femoral inorganic elements content and ash weight in rats].
Chen, X; Wei, J; Chen, Y
1998-02-01
To explore the mechanism of Shenxu Gutong Capsule (SXGTC) in treating postmenopausal osteoporosis. Using ovariectomized rats as the model of postmenopausal osteoporosis, the effect of SXGTC on inorganic element content of femur and femoral ash weight of the model rats were surveyed. Animals were divided into model group, SXGTC high dose group, SXGTC low dose group, positive control group (treated with Gushukang) and normal control group. The medication began at one week after operation and lasting for 120 days. The contents of inorganic elements, including Ca, P, Mg, Zn, Cu and Mn in the three medicated groups were higher than those of the model group (P < 0.01). The effect of SXGTC was dose dependent. The difference between the SXGTC groups and the positive control group was insignificant. The femoral ash weight of the SXGTC high dose group and the positive control group was significantly higher than that of the model group (P < 0.01). SXGTC could antagonize the rat's bony change caused by ovariectomy to increase the inorganic contents in bone, which may, in grneral, lead to a bone-strengthening effect.
Ultrasonic phased array controller for hyperthermia applications.
Benkeser, P J; Pao, T L; Yoon, Y J
1991-01-01
Multiple and mechanically scanned ultrasound transducer systems have demonstrated the efficacy of using ultrasound to produce deep localized hyperthermia. The use of ultrasonic phased arrays has been proposed as an alternative to these systems. A phased array offers a more flexible approach to heating tumours in that the size, shape, and position of its focal region can be altered during the course of treatment in order to achieve the desired temperature distribution. This added flexibility comes at the cost of increased complexity of the hardware necessary to drive the transducer because each element requires its own amplifer with both phase and amplitude control. In order for phased arrays with large numbers of elements to be feasible for hyperthermia applications, the complexity of this circuitry must be minimized. This paper describes a circuit design which simplifies the electronics required to control a phased array transducer system for hyperthermia applications. The design is capable of controlling virtually any type of phased array transducer operating at frequencies less than 2 MHz. The system performance was verified through beam profile measurements using a 48-element tapered phased array transducer.
Inverse free steering law for small satellite attitude control and power tracking with VSCMGs
NASA Astrophysics Data System (ADS)
Malik, M. S. I.; Asghar, Sajjad
2014-01-01
Recent developments in integrated power and attitude control systems (IPACSs) for small satellite, has opened a new dimension to more complex and demanding space missions. This paper presents a new inverse free steering approach for integrated power and attitude control systems using variable-speed single gimbal control moment gyroscope. The proposed inverse free steering law computes the VSCMG steering commands (gimbal rates and wheel accelerations) such that error signal (difference in command and output) in feedback loop is driven to zero. H∞ norm optimization approach is employed to synthesize the static matrix elements of steering law for a static state of VSCMG. Later these matrix elements are suitably made dynamic in order for the adaptation. In order to improve the performance of proposed steering law while passing through a singular state of CMG cluster (no torque output), the matrix element of steering law is suitably modified. Therefore, this steering law is capable of escaping internal singularities and using the full momentum capacity of CMG cluster. Finally, two numerical examples for a satellite in a low earth orbit are simulated to test the proposed steering law.
Characterizing Observed Limit Cycles in the Cassini Main Engine Guidance Control System
NASA Technical Reports Server (NTRS)
Rizvi, Farheen; Weitl, Raquel M.
2011-01-01
The Cassini spacecraft dynamics-related telemetry during long Main Engine (ME) burns has indicated the presence of stable limit cycles between 0.03-0.04 Hz frequencies. These stable limit cycles cause the spacecraft to possess non-zero oscillating rates for extended periods of time. This indicates that the linear ME guidance control system does not model the complete dynamics of the spacecraft. In this study, we propose that the observed limit cycles in the spacecraft dynamics telemetry appear from a stable interaction between the unmodeled nonlinear elements in the ME guidance control system. Many nonlinearities in the control system emerge from translating the linear engine gimbal actuator (EGA) motion into a spacecraft rotation. One such nonlinearity comes from the gear backlash in the EGA system, which is the focus of this paper. The limit cycle characteristics and behavior can be predicted by modeling this gear backlash nonlinear element via a describing function and studying the interaction of this describing function with the overall dynamics of the spacecraft. The linear ME guidance controller and gear backlash nonlinearity are modeled analytically. The frequency, magnitude, and nature of the limit cycle are obtained from the frequency response of the ME guidance controller and nonlinear element. In addition, the ME guidance controller along with the nonlinearity is simulated. The simulation response contains a limit cycle with similar characterstics as predicted analytically: 0.03-0.04 Hz frequency and stable, sustained oscillations. The analytical and simulated limit cycle responses are compared to the flight telemetry for long burns such as the Saturn Orbit Insertion and Main Engine Orbit Trim Maneuvers. The analytical and simulated limit cycle characteristics compare well with the actual observed limit cycles in the flight telemetry. Both have frequencies between 0.03-0.04 Hz and stable oscillations. This work shows that the stable limit cycles occur due to the interaction between the unmodeled nonlinear elements and linear ME guidance controller.
NASA Astrophysics Data System (ADS)
Elshabasy, Mohamed Mostafa Yousef Bassyouny
In this research, life extending control logic is proposed to reduce the cost of treating the aging problem of military aircraft structures and to avoid catastrophic failures and fatal accidents due to undetected cracks in the airframe components. The life extending control logic is based on load tailoring to facilitate a desired stress sequence that prolongs the structural life of the cracked airframe components by exploiting certain nonlinear crack retardation phenomena. The load is tailored to include infrequent injections of a single-cycle overload or a single-cycle overload and underload. These irregular loadings have an anti-intuitive but beneficial effect, which has been experimentally validated, on the extension of the operational structural life of the aircraft. A rigid six-degree-of freedom dynamic model of a highly maneuverable air vehicle coupled with an elastic dynamic wing model is used to generate the stress history at the lower skin of the wing. A three-dimensional equivalent plate finite element model is used to calculate the stress in the cracked skin. The plate is chosen to be of uniform chord-wise and span-wise thickness where the mechanical properties are assigned using an ad-hoc approach to mimic the full scale wing model. An in-extensional 3-node triangular element is used as the gridding finite element while the aerodynamic load is calculated using the vortex-lattice method where each lattice is laid upon two triangular finite elements with common hypotenuse. The aerodynamic loads, along with the base-excitation which is due to the motion of the rigid aircraft model, are the driving forces acting on the wing finite element model. An aerodynamic control surface is modulated based on the proposed life extending control logic within an existing flight control system without requiring major modification. One of the main goals of life extending control logic is to enhance the aircraft's service life, without incurring significant loss of vehicle dynamic performance. The value of the control-surface deflection angle is modulated so that the created overstress is sufficiently below the yield stress of the panel material. The results show that extension in crack length was reduced by 40% to 75% with an absence of damage mitigation logic. Moreover, the desired structural integrity is satisfied without affecting the air vehicle dynamic performance.
Hansen, Ailin Falkmo; Simić, Anica; Åsvold, Bjørn Olav; Romundstad, Pål Richard; Midthjell, Kristian; Syversen, Tore; Flaten, Trond Peder
2017-03-01
Differences in trace elements levels between individuals with type 2 diabetes and controls have been reported in several studies in various body fluids and tissues, but results have been inconsistent. In order to examine trace element levels in the early phase of type 2 diabetes, we investigated the association between whole blood levels of 26 trace elements and the prevalence of previously undiagnosed, screening-detected type 2 diabetes. The study was conducted as a case-control study nested within the third survey of the population-based Nord-Trøndelag Health Study (HUNT3 Survey). Among participants without previously known diabetes, 128 cases of type 2 diabetes were diagnosed in people with a high diabetes risk score (FINDRISC≥15), and frequency-matched for age and sex with 755 controls. Blood samples were analyzed by high resolution inductively coupled plasma mass spectrometry. Associations between trace element levels and the prevalence of previously undiagnosed type 2 diabetes were evaluated with multivariable conditional logistic regression controlling for age, sex, body mass index, waist-to-hip ratio, education, income, smoking and family history of diabetes. The prevalence of previously undiagnosed type 2 diabetes increased across tertiles/quartiles for cadmium, chromium, iron, nickel, silver and zinc, and decreased with increasing quartiles of bromine (P trend <0.05). After corrections for multiple testing, associations for chromium remained significant (Q trend <0.05), while associations for iron and silver were borderline significant. No associations were found for arsenic, boron, calcium, cesium, copper, gallium, gold, indium, lead, magnesium, manganese, mercury, molybdenum, rubidium, selenium, strontium, tantalum, thallium and tin. Our results suggest a possible role of bromine, cadmium, chromium, iron, nickel, silver and zinc in the development of type 2 diabetes. Copyright © 2016 Elsevier GmbH. All rights reserved.
Difo, V H; Onyike, E; Ameh, D A; Njoku, G C; Ndidi, U S
2015-09-01
This study was conducted to investigate the effect of open and controlled fermentation on the proximate composition, mineral elements, antinutritional factors and flatulence-causing oligosaccharides in Vigna racemosa. The open fermentation was carried out using the microorganisms present in the atmosphere while the controlled fermentation was carried out using Aspergillus niger as a starter. The proximate composition of the Vigna racemosa, some anti-nutrients and the mineral elements were analyzed using standard procedures. The protein content was increased by 12.41 ± 1.73 % during open fermentation while it decreased by 29.42 ± 0.1 % during controlled fermentation. The lipids, carbohydrates, crude fibre and ash content were all reduced in both types of fermentation except the moisture content which increased in controlled fermentation. Apart from calcium, the other elements (Fe, Na, Mg, Zn, and K) suffered reduction in both types of fermentation. The phytate, tannin, alkaloids, hydrogen cyanide, lectins, trypsin inhibitors and oxalate content all had drastic reductions in both types of fermentation. Open and controlled fermentation reduced the levels of both raffinose and stachyose. The percentages of reduction due to controlled fermentation were higher than those of open fermentation in the antinutrients studied. Fermentation is an efficient method for detoxifying the antinutrients in the Vigna racemosa studied in this work.
Forming aspheric optics by controlled deposition
Hawryluk, A.M.
1998-04-28
An aspheric optical element is disclosed formed by depositing material onto a spherical surface of an optical element by controlled deposition to form an aspheric surface of desired shape. A reflecting surface, single or multi-layer, can then be formed on the aspheric surface by evaporative or sputtering techniques. Aspheric optical elements are suitable for deep ultra-violet (UV) and x-ray wavelengths. The reflecting surface may, for example, be a thin ({approx}100 nm) layer of aluminum, or in some cases the deposited modifying layer may function as the reflecting surface. For certain applications, multi-layer reflective surfaces may be utilized, such as chromium-carbon or tungsten-carbon multi-layer, with the number of layers and thickness being determined by the intended application. 4 figs.
Forming aspheric optics by controlled deposition
Hawryluk, Andrew M.
1998-01-01
An aspheric optical element formed by depositing material onto a spherical surface of an optical element by controlled deposition to form an aspheric surface of desired shape. A reflecting surface, single or multi-layer, can then be formed on the aspheric surface by evaporative or sputtering techniques. Aspheric optical elements are suitable for deep ultra-violet (UV) and x-ray wavelengths. The reflecting surface may, for example, be a thin (.about.100 nm) layer of aluminum, or in some cases the deposited modifying layer may function as the reflecting surface. For certain applications, multi-layer reflective surfaces may be utilized, such as chromium-carbon or tungsten-carbon multi-layer, with the number of layers and thickness being determined by the intended application.
Thin, nearly wireless adaptive optical device
NASA Technical Reports Server (NTRS)
Knowles, Gareth (Inventor); Hughes, Eli (Inventor)
2008-01-01
A thin, nearly wireless adaptive optical device capable of dynamically modulating the shape of a mirror in real time to compensate for atmospheric distortions and/or variations along an optical material is provided. The device includes an optical layer, a substrate, at least one electronic circuit layer with nearly wireless architecture, an array of actuators, power electronic switches, a reactive force element, and a digital controller. Actuators are aligned so that each axis of expansion and contraction intersects both substrate and reactive force element. Electronics layer with nearly wireless architecture, power electronic switches, and digital controller are provided within a thin-film substrate. The size and weight of the adaptive optical device is solely dominated by the size of the actuator elements rather than by the power distribution system.
Thin, nearly wireless adaptive optical device
NASA Technical Reports Server (NTRS)
Knowles, Gareth (Inventor); Hughes, Eli (Inventor)
2007-01-01
A thin, nearly wireless adaptive optical device capable of dynamically modulating the shape of a mirror in real time to compensate for atmospheric distortions and/or variations along an optical material is provided. The device includes an optical layer, a substrate, at least one electronic circuit layer with nearly wireless architecture, an array of actuators, power electronic switches, a reactive force element, and a digital controller. Actuators are aligned so that each axis of expansion and contraction intersects both substrate and reactive force element. Electronics layer with nearly wireless architecture, power electronic switches, and digital controller are provided within a thin-film substrate. The size and weight of the adaptive optical device is solely dominated by the size of the actuator elements rather than by the power distribution system.
Thin nearly wireless adaptive optical device
NASA Technical Reports Server (NTRS)
Knowles, Gareth J. (Inventor); Hughes, Eli (Inventor)
2009-01-01
A thin nearly wireless adaptive optical device capable of dynamically modulating the shape of a mirror in real time to compensate for atmospheric distortions and/or variations along an optical material is provided. The device includes an optical layer, a substrate, at least one electronic circuit layer with nearly wireless architecture, an array of actuators, power electronic switches, a reactive force element, and a digital controller. Actuators are aligned so that each axis of expansion and contraction intersects both substrate and reactive force element. Electronics layer with nearly wireless architecture, power electronic switches, and digital controller are provided within a thin-film substrate. The size and weight of the adaptive optical device is solely dominated by the size of the actuator elements rather than by the power distribution system.
Reinforcement Learning with Orthonormal Basis Adaptation Based on Activity-Oriented Index Allocation
NASA Astrophysics Data System (ADS)
Satoh, Hideki
An orthonormal basis adaptation method for function approximation was developed and applied to reinforcement learning with multi-dimensional continuous state space. First, a basis used for linear function approximation of a control function is set to an orthonormal basis. Next, basis elements with small activities are replaced with other candidate elements as learning progresses. As this replacement is repeated, the number of basis elements with large activities increases. Example chaos control problems for multiple logistic maps were solved, demonstrating that the method for adapting an orthonormal basis can modify a basis while holding the orthonormality in accordance with changes in the environment to improve the performance of reinforcement learning and to eliminate the adverse effects of redundant noisy states.
NASA Technical Reports Server (NTRS)
1972-01-01
A terminal area simulation is described which permits analysis and synthesis of current and advanced air traffic management system configurations including ground and airborne instrumentation and new and modified aircraft characteristics. Ground elements in the simulation include navigation aids, surveillance radars, communication links, air-route structuring, ATC procedures, airport geometries and runway handling constraints. Airborne elements include traffic samples with individual aircraft performance and operating characteristics and aircraft navigation equipment. The simulation also contains algorithms for conflict detection, conflict resolution, sequencing and pilot-controller data links. The simulation model is used to determine the sensitivities of terminal area traffic flow, safety and congestion to aircraft performance characteristics, avionics systems, and other ATC elements.
Construction of a Piezoresistive Neural Sensor Array
NASA Technical Reports Server (NTRS)
Carlson, W. B.; Schulze, W. A.; Pilgrim, P. M.
1996-01-01
The construction of a piezoresistive - piezoelectric sensor (or actuator) array is proposed using 'neural' connectivity for signal recognition and possible actuation functions. A closer integration of the sensor and decision functions is necessary in order to achieve intrinsic identification within the sensor. A neural sensor is the next logical step in development of truly 'intelligent' arrays. This proposal will integrate 1-3 polymer piezoresistors and MLC electroceramic devices for applications involving acoustic identification. The 'intelligent' piezoresistor -piezoelectric system incorporates printed resistors, composite resistors, and a feedback for the resetting of resistances. A model of a design is proposed in order to simulate electromechanical resistor interactions. The goal of optimizing a sensor geometry for improving device reliability, training, & signal identification capabilities is the goal of this work. At present, studies predict performance of a 'smart' device with a significant control of 'effective' compliance over a narrow pressure range due to a piezoresistor percolation threshold. An interesting possibility may be to use an array of control elements to shift the threshold function in order to change the level of resistance in a neural sensor array for identification, or, actuation applications. The proposed design employs elements of: (1) conductor loaded polymers for a 'fast' RC time constant response; and (2) multilayer ceramics for actuation or sensing and shifting of resistance in the polymer. Other material possibilities also exist using magnetoresistive layered systems for shifting the resistance. It is proposed to use a neural net configuration to test and to help study the possible changes required in the materials design of these devices. Numerical design models utilize electromechanical elements, in conjunction with structural elements in order to simulate piezoresistively controlled actuators and changes in resistance of sensors. The construction of these devices may show significant improvement in ability to interrogate signals and in the control of effective compliance. This work focuses on the development a variety of series/parallel interconnected piezoresistive control elements for the neural sensing function.
Zebrafish U6 small nuclear RNA gene promoters contain a SPH element in an unusual location.
Halbig, Kari M; Lekven, Arne C; Kunkel, Gary R
2008-09-15
Promoters for vertebrate small nuclear RNA (snRNA) genes contain a relatively simple array of transcriptional control elements, divided into proximal and distal regions. Most of these genes are transcribed by RNA polymerase II (e.g., U1, U2), whereas the U6 gene is transcribed by RNA polymerase III. Previously identified vertebrate U6 snRNA gene promoters consist of a proximal sequence element (PSE) and TATA element in the proximal region, plus a distal region with octamer (OCT) and SphI postoctamer homology (SPH) elements. We have found that zebrafish U6 snRNA promoters contain the SPH element in a novel proximal position immediately upstream of the TATA element. The zebrafish SPH element is recognized by SPH-binding factor/selenocysteine tRNA gene transcription activating factor/zinc finger protein 143 (SBF/Staf/ZNF143) in vitro. Furthermore, a zebrafish U6 promoter with a defective SPH element is inefficiently transcribed when injected into embryos.
Functional analysis of the sea urchin-derived arylsulfatase (Ars)-element in mammalian cells.
Watanabe, Satoshi; Watanabe, Sachiko; Sakamoto, Naoaki; Sato, Masahiro; Akasaka, Koji
2006-09-01
An insulator is a DNA sequence that has both enhancer-blocking activity, through its ability to modify the influence of neighboring cis-acting elements, and a barrier function that protects a transgene from being silenced by surrounding chromatin. Previously, we isolated and characterized a 582-bp-long element from the sea urchin arylsulfatase gene (Ars). This Ars-element was effective in sea urchin and Drosophila embryos and in plant cells. To investigate Ars-element activity in mammalian cells, we placed the element between the cytomegalovirus enhancer and a luciferase (luc) expression cassette. In contrast to controls lacking the Ars-element, NIH3T3 and 293T cells transfected with the element-containing construct displayed reduced luciferase activities. The Ars-element therefore acts as an enhancer-blocking element in mammalian cells. We assessed the barrier activity of the Ars-element using vectors in which a luc expression cassette was placed between two elements. Transfection experiments demonstrated that luc activity in these vectors was approximately ten-fold higher than in vectors lacking elements. Luc activities were well maintained even after 12 weeks in culture. Our observations demonstrate that the Ars-element has also a barrier activity. These results indicated that the Ars-element act as an insulator in mammalian cells.
Heyes, Andrew; Rowe, Christopher L; Conrad, Phillip
2014-01-01
We performed an experiment in which larval gray tree frogs (Hyla chrysoscelis) were raised through metamorphosis on diets increased with a suite of elements associated with coal combustion residues (silver [Ag], arsenic [As], cadmium [Cd], chromium [Cr], copper [Cu], mercury [Hg], lead [Pb], selenium [Se], vanadium [V], and zinc [Zn]) at "low" and "high" concentrations. We quantified accumulation of metals at three life stages (mid-larval development, initiation of metamorphosis, and completion of metamorphosis) as well as effects on survival, metabolic rate, size at metamorphosis, and duration and loss of weight during metamorphosis. Most elements were accumulated in a dose-dependent pattern by some or all life stages, although this was not the case for Hg. For most elements, larval body burdens exceeded those of later life stages in some or all treatments (control, low, or high). However for Se, As, and Hg, body burdens in control and low concentrations were increased in later compared with earlier life stages. A lack of dose-dependent accumulation of Hg suggests that the presence of high concentrations of other elements (possibly Se) either inhibited accumulation or increased depuration of Hg. The duration of metamorphosis (forelimb emergence through tail resorption) was lengthened in individuals exposed to the highest concentrations of elements, but there were no other statistically significant biological effects. This study shows that patterns of accumulation and possibly depuration of metals and trace elements are complex in animals possessing complex life cycles. Further study is required to determine specific interactions affecting these patterns, in particular which elements may be responsible for affecting accumulation or retention of Hg when organisms are exposed to complex mixtures of elements.
Schroeder, Mark D.; Greer, Christina; Gaul, Ulrike
2011-01-01
The generation of metameric body plans is a key process in development. In Drosophila segmentation, periodicity is established rapidly through the complex transcriptional regulation of the pair-rule genes. The ‘primary’ pair-rule genes generate their 7-stripe expression through stripe-specific cis-regulatory elements controlled by the preceding non-periodic maternal and gap gene patterns, whereas ‘secondary’ pair-rule genes are thought to rely on 7-stripe elements that read off the already periodic primary pair-rule patterns. Using a combination of computational and experimental approaches, we have conducted a comprehensive systems-level examination of the regulatory architecture underlying pair-rule stripe formation. We find that runt (run), fushi tarazu (ftz) and odd skipped (odd) establish most of their pattern through stripe-specific elements, arguing for a reclassification of ftz and odd as primary pair-rule genes. In the case of run, we observe long-range cis-regulation across multiple intervening genes. The 7-stripe elements of run, ftz and odd are active concurrently with the stripe-specific elements, indicating that maternal/gap-mediated control and pair-rule gene cross-regulation are closely integrated. Stripe-specific elements fall into three distinct classes based on their principal repressive gap factor input; stripe positions along the gap gradients correlate with the strength of predicted input. The prevalence of cis-elements that generate two stripes and their genomic organization suggest that single-stripe elements arose by splitting and subfunctionalization of ancestral dual-stripe elements. Overall, our study provides a greatly improved understanding of how periodic patterns are established in the Drosophila embryo. PMID:21693522
Microcomputer Controlled Experiments.
ERIC Educational Resources Information Center
Kirkman, John; Knaggs, David
1982-01-01
Describes a microcomputer-controlled system which determines the current/voltage characteristics of a resistor, lamp, and diode, detailing system elements, construction, and providing printout of the program developed to provide control and arithmetic functions necessary to complete the experiment. (SK)
Biogeochemical variability of plants at native and altered sites, San Juan Basin, New Mexico
Gough, L.P.; Severson, R.C.
1981-01-01
The San Juan Basin is becoming a major energy resource region. The anticipated increase in strip mining for coal can be expected to alter the geochemical and biogeochemical environment. because such activities destroy the native vegetation communities, rearrange the rock strata, and disrupt natural soil development. This study investigated the variability in the biogeochemistry of native plant species at both undisturbed and altered sites and assessed the importance of the observed differences. Three studies are involved in this investigation: Study 1, the biogeochemical variability of native species found at sites throughout that part of the basin underlain by economically recoverable coal; Study 2, the biogeochemical variability of native species growing on soils considered favorable for use in the topsoiling of spoil areas; and Study 3, the biogeochemical variability of native species on rehabilitated sites at the San Juan coal mine. Summary statistics for concentrations of 35 elements (and ash yield) are reported in Study 1 for galleta grass, broom snakeweed, and fourwing saltbush. The concentrations of manganese, molybdenum, nickel, and uranium (and possibly iron and selenium) in galleta show regional patterns, with the highest values generally found in the south-central region and western edge of the study area. Differences in the concentration of elements between species was generally subtle (less than a factor of two) except for the following: ash yield of saltbush was two times that of the other plants; boron in snakeweed and saltbush was four times greater than in galleta; iron in galleta was two times greater than in saltbush; and, calcium, magnesium, potassium, phosphorus, and sulfur were generally highest in saltbush. Summary statistics (including the 95-percent expected range) for concentrations of 35 elements (and ash yield) are reported from Study 2 for galleta and broom snakeweed growing on the Sheppard, Shiprock, and Doak soil association. Significant regional (greater than 10 km) variation for aluminum, iron, sulfur, vanadium, and zirconium in galleta are reported; however, for most elements, a significant proportion of the variation in the data was measured locally (less than 0.1 km). This variation indicates that samples of galleta and snakeweed taken more than 10 km apart vary, in their element composition, little more than plants sampled as close together as 0.1 km. The concentrations of 35 elements (and ash yield) in alkali sacaton and fourwing saltbush, which were collected on a rehabilitation plot at the San Juan mine (Study 3), are compared with those of control samples of similar material from native sites from throughout the ,an Juan Basin. Concentrations of aluminum, arsenic, boron, cobalt, copper, fluorine, iron, lead, manganese, sodium, and uranium in samples of saltbush growing over spoil generally exceed the levels of these elements in control samples. For many elements, concentrations in mine samples are from two to five times higher 1 han concentrations in the control samples. Sodium concentrations i saltbush, however, were 100 times higher in mine samples than in control samples. This high concentration reflects a corresponding : OO-fold increase in the extractable sodium levels in spoil material s compared to C-horizon control samples. Sampled plants from the l1ine area, spaced relatively close together (5 m (meters) or less), vary greatly in their element compositions, apparently in response 1 J the heterogenous composition and element availability of the l1ine soils. Topsoiling to a depth of 20 cm (centimeters) does little to meliorate the uptake of elements from spoil by saltbush.
NASA Astrophysics Data System (ADS)
Kuznetsov, P. A.; Kovalev, I. V.; Losev, V. V.; Kalinin, A. O.; Murygin, A. V.
2016-04-01
The article discusses the reliability of automated control systems. Analyzes the approach to the classification systems for health States. This approach can be as traditional binary approach, operating with the concept of "serviceability", and other variants of estimation of the system state. This article provides one such option, providing selective evaluation of components for the reliability of the entire system. Introduced description of various automatic control systems and their elements from the point of view of health and risk, mathematical method of determining the transition object from state to state, they differ from each other in the implementation of the objective function. Explores the interplay of elements in different States, the aggregate state of the elements connected in series or in parallel. Are the tables of various logic States and the principles of their calculation in series and parallel connection. Through simulation the proposed approach is illustrated by finding the probability of getting into the system state data in parallel and serially connected elements, with their different probabilities of moving from state to state. In general, the materials of article will be useful for analyzing of the reliability the automated control systems and engineering of the highly-reliable systems. Thus, this mechanism to determine the State of the system provides more detailed information about it and allows a selective approach to the reliability of the system as a whole. Detailed results when assessing the reliability of the automated control systems allows the engineer to make an informed decision when designing means of improving reliability.
40 CFR 86.1803-01 - Definitions.
Code of Federal Regulations, 2011 CFR
2011-07-01
... operator prior to procurement. Auxiliary Emission Control Device (AECD) means any element of design which... components are those components which are designed primarily for emission control, or whose failure may... of design means any control system (i.e., computer software, electronic control system, emission...
40 CFR 86.1803-01 - Definitions.
Code of Federal Regulations, 2012 CFR
2012-07-01
... prior to procurement. Auxiliary Emission Control Device (AECD) means any element of design which senses... components are those components which are designed primarily for emission control, or whose failure may... of design means any control system (i.e., computer software, electronic control system, emission...
Code of Federal Regulations, 2011 CFR
2011-01-01
... STANDARDS: NORMAL CATEGORY ROTORCRAFT Design and Construction Control Systems § 27.671 General. (a) Each control and control system must operate with the ease, smoothness, and positiveness appropriate to its function. (b) Each element of each flight control system must be designed, or distinctively and permanently...
Code of Federal Regulations, 2012 CFR
2012-01-01
... STANDARDS: NORMAL CATEGORY ROTORCRAFT Design and Construction Control Systems § 27.671 General. (a) Each control and control system must operate with the ease, smoothness, and positiveness appropriate to its function. (b) Each element of each flight control system must be designed, or distinctively and permanently...
Code of Federal Regulations, 2010 CFR
2010-01-01
... STANDARDS: NORMAL CATEGORY ROTORCRAFT Design and Construction Control Systems § 27.671 General. (a) Each control and control system must operate with the ease, smoothness, and positiveness appropriate to its function. (b) Each element of each flight control system must be designed, or distinctively and permanently...
Code of Federal Regulations, 2013 CFR
2013-01-01
... STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Design and Construction Control Systems § 29.671 General. (a) Each control and control system must operate with the ease, smoothness, and positiveness appropriate to its function. (b) Each element of each flight control system must be designed, or distinctively and permanently...
Code of Federal Regulations, 2014 CFR
2014-01-01
... STANDARDS: TRANSPORT CATEGORY AIRPLANES Design and Construction Control Systems § 25.671 General. (a) Each control and control system must operate with the ease, smoothness, and positiveness appropriate to its function. (b) Each element of each flight control system must be designed, or distinctively and permanently...
Code of Federal Regulations, 2012 CFR
2012-01-01
... STANDARDS: TRANSPORT CATEGORY AIRPLANES Design and Construction Control Systems § 25.671 General. (a) Each control and control system must operate with the ease, smoothness, and positiveness appropriate to its function. (b) Each element of each flight control system must be designed, or distinctively and permanently...
Code of Federal Regulations, 2010 CFR
2010-01-01
... STANDARDS: TRANSPORT CATEGORY AIRPLANES Design and Construction Control Systems § 25.671 General. (a) Each control and control system must operate with the ease, smoothness, and positiveness appropriate to its function. (b) Each element of each flight control system must be designed, or distinctively and permanently...
Code of Federal Regulations, 2013 CFR
2013-01-01
... STANDARDS: NORMAL CATEGORY ROTORCRAFT Design and Construction Control Systems § 27.671 General. (a) Each control and control system must operate with the ease, smoothness, and positiveness appropriate to its function. (b) Each element of each flight control system must be designed, or distinctively and permanently...
Code of Federal Regulations, 2014 CFR
2014-01-01
... STANDARDS: NORMAL CATEGORY ROTORCRAFT Design and Construction Control Systems § 27.671 General. (a) Each control and control system must operate with the ease, smoothness, and positiveness appropriate to its function. (b) Each element of each flight control system must be designed, or distinctively and permanently...
Code of Federal Regulations, 2011 CFR
2011-01-01
... STANDARDS: TRANSPORT CATEGORY AIRPLANES Design and Construction Control Systems § 25.671 General. (a) Each control and control system must operate with the ease, smoothness, and positiveness appropriate to its function. (b) Each element of each flight control system must be designed, or distinctively and permanently...
NASA Technical Reports Server (NTRS)
Becker, D. D.
1980-01-01
The orbiter subsystems and interfacing program elements which interact with the orbiter computer flight software are analyzed. The failure modes identified in the subsystem/element failure mode and effects analysis are examined. Potential interaction with the software is examined through an evaluation of the software requirements. The analysis is restricted to flight software requirements and excludes utility/checkout software. The results of the hardware/software interaction analysis for the forward reaction control system are presented.
Analysis of Piezoelectric Actuator for Vibration Control of Composite plate
NASA Astrophysics Data System (ADS)
Gomaa, Ahmed R.; Hai, Huang
2017-07-01
Vibration analysis is studied numerically in this paper for a simply supported composite plate subjected to external loadings. Vibrations are controlled by using piezoelectric patches. Finite element method (ANSYS) is used for obtaining finite element model of the smart plate structure, a layered composite plate is manufactured experimentally and tested to obtain the structure mechanical properties. Different piezoelectric patch areas and different applied gain voltage effects on vibration attenuation is studied. The numerical solution is compared with the experimental work, a good agreement achieved.
Approaches to the automatic generation and control of finite element meshes
NASA Technical Reports Server (NTRS)
Shephard, Mark S.
1987-01-01
The algorithmic approaches being taken to the development of finite element mesh generators capable of automatically discretizing general domains without the need for user intervention are discussed. It is demonstrated that because of the modeling demands placed on a automatic mesh generator, all the approaches taken to date produce unstructured meshes. Consideration is also given to both a priori and a posteriori mesh control devices for automatic mesh generators as well as their integration with geometric modeling and adaptive analysis procedures.
Language Measure for Robust Optimal Control
2006-01-01
ROBUST OPTIMAL CONTROL 6. AUTHOR(S) Asok Ray , Travis Ortogero 5. FUNDING NUMBERS C - F30602-01-2-0575 PE - 62301E PR - M414...element of Π is non-negative, so each element of kΠ is also. Thus, 0][ 1 ≥Π− −I elementwise. ■ Wang and Ray [WR02] and Ray and Phoha [RP02] have...Sell, Linear Operator Theory in Science and Engineering, Springer-Verlag, New York, 1982. [RP02] A. Ray and S. Phoha, “A language measure for
NASA Astrophysics Data System (ADS)
Danilova, Olga; Semenova, Zinaida
2018-04-01
The objective of this study is a detailed analysis of physical protection systems development for information resources. The optimization theory and decision-making mathematical apparatus is used to formulate correctly and create an algorithm of selection procedure for security systems optimal configuration considering the location of the secured object’s access point and zones. The result of this study is a software implementation scheme of decision-making system for optimal placement of the physical access control system’s elements.
Developmentally arrested structures preceding cerebellar tumors in von Hippel–Lindau disease
Shively, Sharon B; Falke, Eric A; Li, Jie; Tran, Maxine G B; Thompson, Eli R; Maxwell, Patrick H; Roessler, Erich; Oldfield, Edward H; Lonser, Russell R; Vortmeyer, Alexander O
2011-01-01
There is increasing evidence that suggests that knockout of tumor-suppressor gene function causes developmental arrest and protraction of cellular differentiation. In the peripheral nervous system of patients with the tumor-suppressor gene disorder, von Hippel–Lindau disease, we have demonstrated developmentally arrested structural elements composed of hemangioblast progenitor cells. Some developmentally arrested structural elements progress to a frank tumor, hemangioblastoma. However, in von Hippel–Lindau disease, hemangioblastomas are frequently observed in the cerebellum, suggesting an origin in the central nervous system. We performed a structural and topographic analysis of cerebellar tissues obtained from von Hippel–Lindau disease patients to identify and characterize developmentally arrested structural elements in the central nervous system. We examined the entire cerebella of five tumor-free von Hippel–Lindau disease patients and of three non-von Hippel–Lindau disease controls. In all, 9 cerebellar developmentally arrested structural elements were detected and topographically mapped in 385 blocks of von Hippel–Lindau disease cerebella. No developmentally arrested structural elements were seen in 214 blocks from control cerebella. Developmentally arrested structural elements are composed of poorly differentiated cells that express hypoxia-inducible factor (HIF)2α, but not HIF1α or brachyury, and preferentially involve the molecular layer of the dorsum cerebelli. For the first time, we identify and characterize developmentally arrested structural elements in the central nervous system of von Hippel–Lindau patients. We provide evidence that developmentally arrested structural elements in the cerebellum are composed of developmentally arrested hemangioblast progenitor cells in the molecular layer of the dorsum cerebelli. PMID:21499240
Overview of space power electronic's technology under the CSTI High Capacity Power Program
NASA Technical Reports Server (NTRS)
Schwarze, Gene E.
1994-01-01
The Civilian Space Technology Initiative (CSTI) is a NASA Program targeted at the development of specific technologies in the areas of transportation, operations and science. Each of these three areas consists of major elements and one of the operation's elements is the High Capacity Power element. The goal of this element is to develop the technology base needed to meet the long duration, high capacity power requirements for future NASA initiatives. The High Capacity Power element is broken down into several subelements that includes energy conversion in the areas of the free piston Stirling power converter and thermoelectrics, thermal management, power management, system diagnostics, and environmental compatibility and system's lifetime. A recent overview of the CSTI High capacity Power element and a description of each of the program's subelements is given by Winter (1989). The goals of the Power Management subelement are twofold. The first is to develop, test, and demonstrate high temperature, radiation-resistant power and control components and circuits that will be needed in the Power Conditioning, Control and Transmission (PCCT) subsystem of a space nuclear power system. The results obtained under this goal will also be applicable to the instrumentation and control subsystem of a space nuclear reactor. These components and circuits must perform reliably for lifetimes of 7-10 years. The second goal is to develop analytical models for use in computer simulations of candidate PCCT subsystems. Circuits which will be required for a specific PCCT subsystem will be designed and built to demonstrate their performance and, also, to validate the analytical models and simulations. The tasks under the Power Management subelement will now be described in terms of objectives, approach and present status of work.
a Method for Preview Vibration Control of Systems Having Forcing Inputs and Rapidly-Switched Dampers
NASA Astrophysics Data System (ADS)
ElBeheiry, E. M.
1998-07-01
In a variety of applications, especially in large scale dynamic systems, the mechanization of different vibration control elements in different locations would be decided by limitations placed on the modal vibration of the system and the inherent dynamic coupling between its modes. Also, the quality of vibration control to the economy of producing the whole system would be another trade-off leading to a mix of passive, active and semi-active vibration control elements in one system. This termactiveis limited to externally powered vibration control inputs and the termsemi-activeis limited to rapidly switched dampers. In this article, an optimal preview control method is developed for application to dynamic systems having active and semi-active vibration control elements mechanized at different locations in one system. The system is then a piecewise (bilinear) controller in which two independent sets of control inputs appear additively and multiplicatively. Calculus of variations along with the Hamiltonian approach are employed for the derivation of this method. In essence, it requires the active elements to be ideal force generators and the switched dampers to have the property of on-line variation of the damping characteristics to pre-determined limits. As the dampers switch during operation the whole system's structure differs, and then values of the active forcing inputs are adapted to match these rapid changes. Strictly speaking, each rapidly switched damper has pre-known upper and lower damping levels and it can take on any in-between value. This in-between value is to be determined by the method as long as the damper tracks a pre-known fully active control demand. In every damping state of each semi-active damper the method provides the optimal matching values of the active forcing inputs. The method is shown to have the feature of solving simple standard matrix equations to obtain closed form solutions. A comprehensive 9-DOF tractor semi-trailer model is used to demonstrate the effectiveness of the method. Time domain predictions are made to compare performance of ride and tyre-to-road contact in the model for the presented method with those of some other active and semi-active suspension designs.
Active Robust Control of Elastic Blade Element Containing Magnetorheological Fluid
NASA Astrophysics Data System (ADS)
Sivrioglu, Selim; Cakmak Bolat, Fevzi
2018-03-01
This research study proposes a new active control structure to suppress vibrations of a small-scale wind turbine blade filled with magnetorheological (MR) fluid and actuated by an electromagnet. The aluminum blade structure is manufactured using the airfoil with SH3055 code number which is designed for use on small wind turbines. An interaction model between MR fluid and the electromagnetic actuator is derived. A norm based multi-objective H2/H∞ controller is designed using the model of the elastic blade element. The H2/H∞ controller is experimentally realized under the impact and steady state aerodynamic load conditions. The results of experiments show that the MR fluid is effective for suppressing vibrations of the blade structure.
Mesh control information of windmill designed by Solidwork program
NASA Astrophysics Data System (ADS)
Mulyana, T.; Sebayang, D.; Rafsanjani, A. M. D.; Adani, J. H. D.; Muhyiddin, Y. S.
2017-12-01
This paper presents the mesh control information imposed on the windmill already designed. The accuracy of Simulation results is influenced by the quality of the created mesh. However, compared to the quality of the mesh is made, the simulation time running will be done software also increases. The smaller the size of the elements created when making the mesh, the better the mesh quality will be generated. When adjusting the mesh size, there is a slider that acts as the density regulator of the element. SolidWorks Simulation also has Mesh Control facility. Features that can adjust mesh density only in the desired part. The best results of mesh control obtained for both static and thermal simulation have ratio 1.5.
Advanced flight control system study
NASA Technical Reports Server (NTRS)
Hartmann, G. L.; Wall, J. E., Jr.; Rang, E. R.; Lee, H. P.; Schulte, R. W.; Ng, W. K.
1982-01-01
A fly by wire flight control system architecture designed for high reliability includes spare sensor and computer elements to permit safe dispatch with failed elements, thereby reducing unscheduled maintenance. A methodology capable of demonstrating that the architecture does achieve the predicted performance characteristics consists of a hierarchy of activities ranging from analytical calculations of system reliability and formal methods of software verification to iron bird testing followed by flight evaluation. Interfacing this architecture to the Lockheed S-3A aircraft for flight test is discussed. This testbed vehicle can be expanded to support flight experiments in advanced aerodynamics, electromechanical actuators, secondary power systems, flight management, new displays, and air traffic control concepts.
GVE-Based Dynamics and Control for Formation Flying Spacecraft
NASA Technical Reports Server (NTRS)
Breger, Louis; How, Jonathan P.
2004-01-01
Formation flying is an enabling technology for many future space missions. This paper presents extensions to the equations of relative motion expressed in Keplerian orbital elements, including new initialization techniques for general formation configurations. A new linear time-varying form of the equations of relative motion is developed from Gauss Variational Equations and used in a model predictive controller. The linearizing assumptions for these equations are shown to be consistent with typical formation flying scenarios. Several linear, convex initialization techniques are presented, as well as a general, decentralized method for coordinating a tetrahedral formation using differential orbital elements. Control methods are validated using a commercial numerical propagator.
Systems and methods for commutating inductor current using a matrix converter
Ransom, Ray M; Kajouke, Lateef A; Perisic, Milun
2012-10-16
Systems and methods are provided for delivering current using a matrix converter in a vehicle. An electrical system comprises an AC interface, a first conversion module coupled to the AC interface, an inductive element coupled between the AC interface and the first conversion module, and a control module coupled to the first conversion module. The control module is configured to operate the first conversion module in a bidirectional operating mode to commutate current bidirectionally. When a magnitude of the current through the inductive element is greater than a first threshold value, the control module operates the conversion module in a unidirectional operating mode, wherein current is commutated unidirectionally.
AUTOMATIC FREQUENCY CONTROL SYSTEM
Hansen, C.F.; Salisbury, J.D.
1961-01-10
A control is described for automatically matching the frequency of a resonant cavity to that of a driving oscillator. The driving oscillator is disconnected from the cavity and a secondary oscillator is actuated in which the cavity is the frequency determining element. A low frequency is mixed with the output of the driving oscillator and the resultant lower and upper sidebands are separately derived. The frequencies of the sidebands are compared with the secondary oscillator frequency. deriving a servo control signal to adjust a tuning element in the cavity and matching the cavity frequency to that of the driving oscillator. The driving oscillator may then be connected to the cavity.
High performance N2O4/amine elements: Blowapart
NASA Technical Reports Server (NTRS)
Lawver, B. R.
1977-01-01
The mechanisms controlling hypergolic propellant reactive stream separation (RRS) were studied and used to develop design criteria for injectors free from both steady state RSS and cyclic propellant stream separation. This was accomplished through the analysis of single element injectors using N204/MMH propellants; the injectors were representative of the space shuttle orbit maneuvering engine and space tug applications. A gas phase/surface reaction mechanism which controls RSS was identified. Injector design criteria were developed, which defined a critical chamber pressure for those operating conditions above which RSS occurs. It was found that the amount of interfacial surface area at impingement is controlled by injector hydraulics.
14 CFR 23.685 - Control system details.
Code of Federal Regulations, 2010 CFR
2010-01-01
... Control Systems § 23.685 Control system details. (a) Each detail of each control system must be designed... cables or tubes against other parts. (d) Each element of the flight control system must have design... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Control system details. 23.685 Section 23...
14 CFR 23.685 - Control system details.
Code of Federal Regulations, 2011 CFR
2011-01-01
... Control Systems § 23.685 Control system details. (a) Each detail of each control system must be designed... cables or tubes against other parts. (d) Each element of the flight control system must have design... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Control system details. 23.685 Section 23...
14 CFR 23.685 - Control system details.
Code of Federal Regulations, 2013 CFR
2013-01-01
... Control Systems § 23.685 Control system details. (a) Each detail of each control system must be designed... cables or tubes against other parts. (d) Each element of the flight control system must have design... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Control system details. 23.685 Section 23...
14 CFR 23.685 - Control system details.
Code of Federal Regulations, 2014 CFR
2014-01-01
... Control Systems § 23.685 Control system details. (a) Each detail of each control system must be designed... cables or tubes against other parts. (d) Each element of the flight control system must have design... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Control system details. 23.685 Section 23...
14 CFR 23.685 - Control system details.
Code of Federal Regulations, 2012 CFR
2012-01-01
... Control Systems § 23.685 Control system details. (a) Each detail of each control system must be designed... cables or tubes against other parts. (d) Each element of the flight control system must have design... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Control system details. 23.685 Section 23...
Impact of low level radiation on concentrations of some trace elements in radiation workers.
Rostampour, Nima; Almasi, Tinoosh; Rostampour, Masoumeh; Sadeghi, Hamid Reza; Khodamoradi, Ehsan; Razi, Reyhaneh; Derakhsh, Zahra
2018-05-01
Small variations in trace element levels may cause important physiological changes in the human body. This study aims to evaluate five important trace elements in radiation workers. In this study, 44 radiation workers and an equal number of non-radiation workers were selected as the case and control group, respectively. The concentrations of iron, magnesium, zinc, copper, and selenium in the serum of the participants were measured using an Atomic Absorption Spectrometry (AAS). The mean concentrations of iron, magnesium, zinc, copper, and selenium for the case group were 107.3 µg/dl, 2.3 mg/dl, 80.9 µg/dl, 112.6 µg/dl and 216.7 ng/ml, respectively. The results for the control group were 121.9 µg/dl, 2.3 mg/dl, 82.3 µg/dl, 112.8 µg/dl and 225.2 ng/ml, respectively. The mean concentration of iron in the case group was significantly lower than the control group (p-value = 0.012), while the concentrations of other elements in both of the groups were not significantly different. In the case group, except magnesium (p-value = 0.021), no significant relationship was found between age and the elemental concentrations. According to Spearman's test, there was a meaningful statistical correlation between the sex and concentration of iron, Mg, Zn, and Se. Also, the correlation between the concentration of magnesium and the weights of radiation workers was significant (p-value =0.044). © 2018 Old City Publishing, Inc.
Controls on Fe(II)-Activated Trace Element Release from Goethite and Hematite
DOE Office of Scientific and Technical Information (OSTI.GOV)
Frierdich, Andrew J.; Catalano, Jeffrey G.
2012-03-26
Electron transfer and atom exchange (ETAE) between aqueous Fe(II) and Fe(III) oxides induces surface growth and dissolution that affects trace element fate and transport. We have recently demonstrated Ni(II) cycling through goethite and hematite (adsorbed Ni incorporates into the mineral structure and preincorporated Ni releases to solution) during Fe(II)-Fe(III) ETAE. However, the chemical parameters affecting net trace element release remain unknown. Here, we examine the chemical controls on Ni(II) and Zn(II) release from Ni- and Zn-substituted goethite and hematite during reaction with Fe(II). Release follows a rate law consistent with surface reaction limited mineral dissolution and suggests that release occursmore » near sites of Fe(III) reductive dissolution during Fe(II)-Fe(III) ETAE. Metal substituent type affects reactivity; Zn release is more pronounced from hematite than goethite, whereas the opposite trend occurs for Ni. Buildup of Ni or Zn in solution inhibits further release but this resumes upon fluid exchange, suggesting that sustained release is possible under flow conditions. Mineral and aqueous Fe(II) concentrations as well as pH strongly affect sorbed Fe(II) concentrations, which directly control the reaction rates and final metal concentrations. Our results demonstrate that structurally incorporated trace elements are mobilized from iron oxides into fluids without abiotic or microbial net iron reduction. Such release may affect micronutrient availability, contaminant transport, and the distribution of redox-inactive trace elements in natural and engineered systems.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kwon, Deug-Nam; Park, Mi-Ryung; Park, Jong-Yi
Highlights: {yields} The sequences of -604 to -84 bp of the pUPII promoter contained the region of a putative negative cis-regulatory element. {yields} The core promoter was located in the 5F-1. {yields} Transcription factor HNF4 can directly bind in the pUPII core promoter region, which plays a critical role in controlling promoter activity. {yields} These features of the pUPII promoter are fundamental to development of a target-specific vector. -- Abstract: Uroplakin II (UPII) is a one of the integral membrane proteins synthesized as a major differentiation product of mammalian urothelium. UPII gene expression is bladder specific and differentiation dependent, butmore » little is known about its transcription response elements and molecular mechanism. To identify the cis-regulatory elements in the pig UPII (pUPII) gene promoter region, we constructed pUPII 5' upstream region deletion mutants and demonstrated that each of the deletion mutants participates in controlling the expression of the pUPII gene in human bladder carcinoma RT4 cells. We also identified a new core promoter region and putative negative cis-regulatory element within a minimal promoter region. In addition, we showed that hepatocyte nuclear factor 4 (HNF4) can directly bind in the pUPII core promoter (5F-1) region, which plays a critical role in controlling promoter activity. Transient cotransfection experiments showed that HNF4 positively regulates pUPII gene promoter activity. Thus, the binding element and its binding protein, HNF4 transcription factor, may be involved in the mechanism that specifically regulates pUPII gene transcription.« less
NASA Astrophysics Data System (ADS)
Sheng, Lizeng
The dissertation focuses on one of the major research needs in the area of adaptive/intelligent/smart structures, the development and application of finite element analysis and genetic algorithms for optimal design of large-scale adaptive structures. We first review some basic concepts in finite element method and genetic algorithms, along with the research on smart structures. Then we propose a solution methodology for solving a critical problem in the design of a next generation of large-scale adaptive structures---optimal placements of a large number of actuators to control thermal deformations. After briefly reviewing the three most frequently used general approaches to derive a finite element formulation, the dissertation presents techniques associated with general shell finite element analysis using flat triangular laminated composite elements. The element used here has three nodes and eighteen degrees of freedom and is obtained by combining a triangular membrane element and a triangular plate bending element. The element includes the coupling effect between membrane deformation and bending deformation. The membrane element is derived from the linear strain triangular element using Cook's transformation. The discrete Kirchhoff triangular (DKT) element is used as the plate bending element. For completeness, a complete derivation of the DKT is presented. Geometrically nonlinear finite element formulation is derived for the analysis of adaptive structures under the combined thermal and electrical loads. Next, we solve the optimization problems of placing a large number of piezoelectric actuators to control thermal distortions in a large mirror in the presence of four different thermal loads. We then extend this to a multi-objective optimization problem of determining only one set of piezoelectric actuator locations that can be used to control the deformation in the same mirror under the action of any one of the four thermal loads. A series of genetic algorithms, GA Version 1, 2 and 3, were developed to find the optimal locations of piezoelectric actuators from the order of 1021 ˜ 1056 candidate placements. Introducing a variable population approach, we improve the flexibility of selection operation in genetic algorithms. Incorporating mutation and hill climbing into micro-genetic algorithms, we are able to develop a more efficient genetic algorithm. Through extensive numerical experiments, we find that the design search space for the optimal placements of a large number of actuators is highly multi-modal and that the most distinct nature of genetic algorithms is their robustness. They give results that are random but with only a slight variability. The genetic algorithms can be used to get adequate solution using a limited number of evaluations. To get the highest quality solution, multiple runs including different random seed generators are necessary. The investigation time can be significantly reduced using a very coarse grain parallel computing. Overall, the methodology of using finite element analysis and genetic algorithm optimization provides a robust solution approach for the challenging problem of optimal placements of a large number of actuators in the design of next generation of adaptive structures.
Small drill-hole, gas mini-permeameter probe
Molz, III, Fred J.; Murdoch, Lawrence C.; Dinwiddie, Cynthia L.; Castle, James W.
2002-12-03
The distal end of a basic tube element including a stopper device with an expandable plug is positioned in a pre-drilled hole in a rock face. Rotating a force control wheel threaded on the tube element exerts force on a sleeve that in turn causes the plug component of the stopper means to expand and seal the distal end of the tube in the hole. Gas under known pressure is introduced through the tube element. A thin capillary tube positioned in the tube element connects the distal end of the tube element to means to detect and display pressure changes and data that allow the permeability of the rock to be determined.
Small drill-hole, gas mini-permeameter probe
Molz, III, Fred J.; Murdoch, Lawrence C.; Dinwiddie, Cynthia L.; Castle, James W.
2002-01-01
The distal end of a basic tube element including a stopper device with an expandable plug is positioned in a pre-drilled hole in a rock face. Rotating a force control wheel threaded on the tube element exerts force on a sleeve that in turn causes the plug component of the stopper means to expand and seal the distal end of the tube in the hole. Gas under known pressure is introduced through the tube element. A thin capillary tube positioned in the tube element connects the distal end of the tube element to means to detect and display pressure changes and data that allow the permeability of the rock to be determined.
NASA Technical Reports Server (NTRS)
Chung, T. J. (Editor); Karr, Gerald R. (Editor)
1989-01-01
Recent advances in computational fluid dynamics are examined in reviews and reports, with an emphasis on finite-element methods. Sections are devoted to adaptive meshes, atmospheric dynamics, combustion, compressible flows, control-volume finite elements, crystal growth, domain decomposition, EM-field problems, FDM/FEM, and fluid-structure interactions. Consideration is given to free-boundary problems with heat transfer, free surface flow, geophysical flow problems, heat and mass transfer, high-speed flow, incompressible flow, inverse design methods, MHD problems, the mathematics of finite elements, and mesh generation. Also discussed are mixed finite elements, multigrid methods, non-Newtonian fluids, numerical dissipation, parallel vector processing, reservoir simulation, seepage, shallow-water problems, spectral methods, supercomputer architectures, three-dimensional problems, and turbulent flows.
10 CFR 55.41 - Written examination: Operators.
Code of Federal Regulations, 2013 CFR
2013-01-01
... elements, control rods, core instrumentation, and coolant flow. (3) Mechanical components and design..., and functions of reactivity control mechanisms and instrumentation. (7) Design, components, and functions of control and safety systems, including instrumentation, signals, interlocks, failure modes, and...
10 CFR 55.41 - Written examination: Operators.
Code of Federal Regulations, 2014 CFR
2014-01-01
... elements, control rods, core instrumentation, and coolant flow. (3) Mechanical components and design..., and functions of reactivity control mechanisms and instrumentation. (7) Design, components, and functions of control and safety systems, including instrumentation, signals, interlocks, failure modes, and...
DOT National Transportation Integrated Search
2014-02-01
This project investigated the impact of varying two elements of pavement, bridge, and mobility asset management on the long term networklevel : performance of those assets. The first element was the condition at which restorative treatments are tr...
Male Germline Control of Transposable Elements1
Bao, Jianqiang; Yan, Wei
2012-01-01
ABSTRACT Repetitive sequences, especially transposon-derived interspersed repetitive elements, account for a large fraction of the genome in most eukaryotes. Despite the repetitive nature, these transposable elements display quantitative and qualitative differences even among species of the same lineage. Although transposable elements contribute greatly as a driving force to the biological diversity during evolution, they can induce embryonic lethality and genetic disorders as a result of insertional mutagenesis and genomic rearrangement. Temporary relaxation of the epigenetic control of retrotransposons during early germline development opens a risky window that can allow retrotransposons to escape from host constraints and to propagate abundantly in the host genome. Because germline mutations caused by retrotransposon activation are heritable and thus can be deleterious to the offspring, an adaptive strategy has evolved in host cells, especially in the germline. In this review, we will attempt to summarize general defense mechanisms deployed by the eukaryotic genome, with an emphasis on pathways utilized by the male germline to confer retrotransposon silencing. PMID:22357546
Passive vibration control: a structure–immittance approach
Zhang, Sara Ying; Neild, Simon A.
2017-01-01
Linear passive vibration absorbers, such as tuned mass dampers, often contain springs, dampers and masses, although recently there has been a growing trend to employ or supplement the mass elements with inerters. When considering possible configurations with these elements broadly, two approaches are normally used: one structure-based and one immittance-based. Both approaches have their advantages and disadvantages. In this paper, a new approach is proposed: the structure–immittance approach. Using this approach, a full set of possible series–parallel networks with predetermined numbers of each element type can be represented by structural immittances, obtained via a proposed general formulation process. Using the structural immittances, both the ability to investigate a class of absorber possibilities together (advantage of the immittance-based approach), and the ability to control the complexity, topology and element values in resulting absorber configurations (advantages of the structure-based approach) are provided at the same time. The advantages of the proposed approach are demonstrated through two case studies on building vibration suppression and automotive suspension design, respectively. PMID:28588407
Passive vibration control: a structure-immittance approach.
Zhang, Sara Ying; Jiang, Jason Zheng; Neild, Simon A
2017-05-01
Linear passive vibration absorbers, such as tuned mass dampers, often contain springs, dampers and masses, although recently there has been a growing trend to employ or supplement the mass elements with inerters. When considering possible configurations with these elements broadly, two approaches are normally used: one structure-based and one immittance-based. Both approaches have their advantages and disadvantages. In this paper, a new approach is proposed: the structure-immittance approach. Using this approach, a full set of possible series-parallel networks with predetermined numbers of each element type can be represented by structural immittances, obtained via a proposed general formulation process. Using the structural immittances, both the ability to investigate a class of absorber possibilities together (advantage of the immittance-based approach), and the ability to control the complexity, topology and element values in resulting absorber configurations (advantages of the structure-based approach) are provided at the same time. The advantages of the proposed approach are demonstrated through two case studies on building vibration suppression and automotive suspension design, respectively.