Svensson, Kristin E; Velandia, Marianne I; Matthiesen, Ann-Sofi T; Welles-Nyström, Barbara L; Widström, Ann-Marie E
2013-03-11
Infants with latch-on problems cause stress for parents and staff, often resulting in early termination of breastfeeding. Healthy newborns experiencing skin-to-skin contact at birth are pre-programmed to find the mother's breast. This study investigates if skin-to-skin contact between mothers with older infants having severe latching on problems would resolve the problem. Mother-infant pairs with severe latch-on problems, that were not resolved during screening procedures at two maternity hospitals in Stockholm 1998-2004, were randomly assigned to skin-to-skin contact (experimental group) or not (control group) during breastfeeding. Breastfeeding counseling was given to both groups according to a standard model. Participants were unaware of their treatment group. Objectives were to compare treatment groups concerning the proportion of infants regularly latching on, the time from intervention to regular latching on and maternal emotions and pain before and during breastfeeding. On hundred and three mother-infant pairs with severe latch-on problems 1-16 weeks postpartum were randomly assigned and analyzed. There was no significant difference between the groups in the proportion of infants starting regular latching-on (75% experimental group, vs. 86% control group). Experimental group infants, who latched on, had a significantly shorter median time from start of intervention to regular latching on than control infants, 2.0 weeks (Q1 = 1.0, Q3 = 3.7) vs. 4.7 weeks (Q1 = 2.0, Q3 = 8.0), (p-value = 0.020). However, more infants in the experimental group (94%), with a history of "strong reaction" during "hands-on latch intervention", latched-on within 3 weeks compared to 33% in the control infants (Fisher Exact test p-value = 0.0001). Mothers in the experimental group (n = 53) had a more positive breastfeeding experience according to the Breastfeeding Emotional Scale during the intervention than mothers in the control group (n = 50) (p-value = 0.022). Skin-to-skin contact during breastfeeding seems to immediately enhance maternal positive feelings and shorten the time it takes to resolve severe latch-on problems in the infants who started to latch. An underlying mechanism may be that skin-to-skin contact with the mother during breastfeeding may calm infants with earlier strong reaction to "hands on latch intervention" and relieve the stress which may have blocked the infant's inborn biological program to find the breast and latch on. Karolinska Clinical Trial Registration number CT20100055.
Resettable binary latch mechanism for use with paraffin linear motors
NASA Technical Reports Server (NTRS)
Maus, Daryl; Tibbitts, Scott
1991-01-01
A new resettable Binary Latch Mechanism was developed utilizing a paraffin actuator as the motor. This linear actuator alternately latches between extended and retracted positions, maintaining either position with zero power consumption. The design evolution and kinematics of the latch mechanism are presented, as well as the development problems and lessons that were learned.
Radial SI latches vibration test data review
NASA Technical Reports Server (NTRS)
Harrison, P. M.; Smith, J. L.
1984-01-01
Dynamic testing of the Space Telescope Scientific Instrument Radial Latches was performed as specified by the designated test criteria. No structural failures were observed during the test. The alignment stability of the instrument simulator was within required tolerances after testing. Particulates were discovered around the latch bases, after testing, due to wearing at the B and C latch interface surfaces. This report covers criteria derivation, testing, and test results.
Pneumatic preloaded scanning science launch latch system
NASA Technical Reports Server (NTRS)
Kievit, J. C.
1979-01-01
A relatively simple system using a preloaded pneumatic piston latch with a pyrotechnic valve release was developed. The system was the only candidate that met all the imposed requirements utilizing reliable state-of-art components. The development of the latch system from its first use on Mariner '69 Mars Flyby Spacecraft through its most recent use on the Voyager Spacecraft that will fly to Jupiter and Saturn is reviewed.
Latch fittings for the scientific instruments on the space telescope
NASA Technical Reports Server (NTRS)
Dozier, J. D.; Kaelber, E.
1983-01-01
Latch fittings which kinematically mount the replaceable scientific instruments onto the Space Telescope must maintain precise alignment and thermal stability for on-orbit observations. Design features which are needed to meet stringent criteria include the use of ceramic isolators for thermal and electrical insulation, materials with different coefficients of thermal expansion for athermalization, precision manufacturing procedures, and extremely tight tolerances. A specific latch fitting to be discussed is a ball-and-socket design. In addition, testing, crew aids, and problems will be covered.
Some aspects of strategies and solutions in accident prevention.
Häkkinen, K
1983-04-01
Accident prevention measures are traditionally classified into technical, organizational and behavioral solutions. A review of some commonly used strategies for accident prevention illustrates some discrepancies between different approaches and the need to develop more comprehensive strategies. Several factors, including protective efficiency and disadvantages at work, must be taken into account when the solutions are evaluated. Some solutions to prevent load disengagement from cranes were evaluated. Measurements of the pressing force showed that the efficiency of the safety latch of a clamp for plate lifting is inadequate to provide protection under all exceptional lifting conditions and in all situations for which the safety latch is intended. The delay caused by the attachment of a lifting hook equipped with a safety latch was measured. The handling of some of the most reliable and technically safe latches requires additional operations and thereby limits their practical application.
Buerger, Stephen; Marron, Lisa C.; Martinez, Michael A.; Spletzer, Barry Louis
2016-12-13
An electromechanical latch is described herein. The electromechanical latch is a dual-actuator latch, wherein a first actuator and a second actuator are driven with precise timing to move a first latch part relative to a second latch part, and vice versa. When the electromechanical latch is in a closed position, the first rotary latch part is positioned to prevent rotation of the second rotary latch part in a first direction. To transition the electromechanical latch from the closed position to an open position, the first actuator drives the first rotary latch part such that the second rotary latch part is able to rotate in the first direction. Thereafter, the second actuator drives the second rotary latch part in the first direction until the electromechanical latch is in the open position.
The X-43 Fin Actuation System Problem - Reliability in Shades of Gray
NASA Technical Reports Server (NTRS)
Peebles, Curtis
2006-01-01
Following the loss of the first X-43 during launch, the mishap investigation board indicated the Fin Actuator System (FAS) needed to have a larger torque margin. To supply this added torque, a second actuator was added. The consequences of what seemed to be a simple modification would trouble the X-43 program. Because of the second actuator, a new computer board was required. This proved to be subject to electronic noise. This resulted in the actuator latch up in ground tests of the FAS for the second launch. Such a latch up would cause the Pegasus booster to fail, as the FAS was a single string system. The problem was corrected and the second flight was successful. The same modifications were added to the FAS for flight three. When the FAS underwent ground tests, it also latched up. The failure indicated that each computer board had a different tolerance to electronic noise. The problem with the FAS was corrected. Subsequently, another failure occurred, raising questions about the design, and the probability of failure for the X-43 Mach 10 flight. This was not simply a technical issue, but illuminated the difficulties facing both managers and engineers in assessing risk, design requirements, and probabilities in cutting edge aerospace projects.
Retaining latch for a water pit gate
Beale, A.R.
1997-11-18
A retaining latch is described for use in a hazardous materials storage or handling facility to adjustably retain a water pit gate in a gate frame. A retaining latch is provided comprising a latch plate which is rotatably mounted to each end of the top of the gate and a recessed opening, formed in the gate frame, for engaging an edge of the latch plate. The latch plate is circular in profile with one side cut away or flat, such that the latch plate is D-shaped. The remaining circular edge of the latch plate comprises steps of successively reduced thickness. The stepped edge of the latch plate fits inside a recessed opening formed in the gate frame. As the latch plate is rotated, alternate steps of the latch plate are engaged by the recessed opening. When the latch plate is rotated such that the flat portion of the latch plate faces the recessed opening in the gate frame, there is no connection between the opening and the latch plate and the gate is unlatched from the gate frame. 4 figs.
NASA Technical Reports Server (NTRS)
Doggett, William R.; Dorsey, John T.; Jones, Thomas C.; King, Bruce D.; Mikulas, Martin M.
2011-01-01
Efficient handling of payloads destined for a planetary surface, such as the moon or mars, requires robust systems to secure the payloads during transport on the ground, in space and on the planetary surface. In addition, mechanisms to release the payloads need to be reliable to ensure successful transfer from one vehicle to another. An efficient payload handling strategy must also consider the devices available to support payload handling. Cranes used for overhead lifting are common to all phases of payload handling on Earth. Similarly, both recent and past studies have demonstrated that devices with comparable functionality will be needed to support lunar outpost operations. A first generation test-bed of a new high performance device that provides the capabilities of both a crane and a robotic manipulator, the Lunar Surface Manipulation System (LSMS), has been designed, built and field tested and is available for use in evaluating a system to secure payloads to transportation vehicles. A payload handling approach must address all phases of payload management including: ground transportation, launch, planetary transfer and installation in the final system. In addition, storage may be required during any phase of operations. Each of these phases requires the payload to be lifted and secured to a vehicle, transported, released and lifted in preparation for the next transportation or storage phase. A critical component of a successful payload handling approach is a latch and associated carrier system. The latch and carrier system should minimize requirements on the: payload, carrier support structure and payload handling devices as well as be able to accommodate a wide range of payload sizes. In addition, the latch should; be small and lightweight, support a method to apply preload, be reusable, integrate into a minimal set of hard-points and have manual interfaces to actuate the latch should a problem occur. A latching system which meets these requirements has been designed and fabricated and will be described in detail. This latching system works in conjunction with a payload handling device such as the LSMS, and the LSMS has been used to test first generation latch and carrier hardware. All tests have been successful during the first phase of operational evaluations. Plans for future tests of first generation latch and carrier hardware with the LSMS are also described.
NASA Technical Reports Server (NTRS)
Doggett, William R.; Dorsey, John T.; Jones, Thomas C.; King, Bruce D.; Mikulas, Martin M.
2010-01-01
Efficient handling of payloads destined for a planetary surface, such as the moon or Mars, requires robust systems to secure the payloads during transport on the ground, in-space and on the planetary surface. In addition, mechanisms to release the payloads need to be reliable to ensure successful transfer from one vehicle to another. An efficient payload handling strategy must also consider the devices available to support payload handling. Cranes used for overhead lifting are common to all phases of payload handling on Earth. Similarly, both recent and past studies have demonstrated that devices with comparable functionality will be needed to support lunar outpost operations. A first generation test-bed of a new high performance device that provides the capabilities of both a crane and a robotic manipulator, the Lunar Surface Manipulation System (LSMS), has been designed, built and field tested and is available for use in evaluating a system to secure payloads to transportation vehicles. National Institute of Aerospace, Hampton Va 23662 A payload handling approach must address all phases of payload management including: ground transportation, launch, planetary transfer and installation in the final system. In addition, storage may be required during any phase of operations. Each of these phases requires the payload to be lifted and secured to a vehicle, transported, released and lifted in preparation for the next transportation or storage phase. A critical component of a successful payload handling approach is a latch and associated carrier system. The latch and carrier system should minimize requirements on the: payload, carrier support structure and payload handling devices as well as be able to accommodate a wide range of payload sizes. In addition, the latch should; be small and lightweight, support a method to apply preload, be reusable, integrate into a minimal set of hard-points and have manual interfaces to actuate the latch should a problem occur. A latching system which meets these requirements has been designed and fabricated and will be described in detail. This latching system works in conjunction with a payload handling device such as the LSMS, and the LSMS has been used to test first generation latch and carrier hardware. All tests have been successful during the first phase of operational evaluations. Plans for future tests of first generation latch and carrier hardware with the LSMS are also described.
CRDM with separate SCRAM latch engagement and locking
DOE Office of Scientific and Technical Information (OSTI.GOV)
Dodd, Christopher D.; DeSantis, Paul K.; Stambaugh, Kevin J.
A control rod drive mechanism (CRDM) configured to latch onto the lifting rod of a control rod assembly and including separate latch engagement and latch holding mechanisms. A CRDM configured to latch onto the lifting rod of a control rod assembly and including a four-bar linkage closing the latch, wherein the four-bar linkage biases the latch closed under force of gravity.
Spletzer, Barry L.; Martinez, Michael A.; Marron, Lisa C.
2012-11-13
A rotary mechanical latch for positive latching and unlatching of a rotary device with a latchable rotating assembly having a latching gear that can be driven to latched and unlatched states by a drive mechanism such as an electric motor. A cam arm affixed to the latching gear interfaces with leading and trailing latch cams affixed to a flange within the drive mechanism. The interaction of the cam arm with leading and trailing latch cams prevents rotation of the rotating assembly by external forces such as those due to vibration or tampering.
Static latching arrangement and method
Morrison, Larry
1988-01-01
A latching assembly for use in latching a cable to and unlatching it from a given object in order to move an object from one location to another is disclosed herein. This assembly includes a weighted sphere mounted to one end of a cable so as to rotate about a specific diameter of the sphere. The assembly also includes a static latch adapted for connection with the object to be moved. This latch includes an internal latching cavity for containing the sphere in a latching condition and a series of surfaces and openings which cooperate with the sphere in order to move the sphere into and out of the latching cavity and thereby connect the cable to and disconnect it from the latch without using any moving parts on the latch itself.
Minimal Power Latch for Single-Slope ADCs
NASA Technical Reports Server (NTRS)
Hancock, Bruce R. (Inventor)
2015-01-01
A latch circuit that uses two interoperating latches. The latch circuit has the beneficial feature that it switches only a single time during a measurement that uses a stair step or ramp function as an input signal in an analog to digital converter. This feature minimizes the amount of power that is consumed in the latch and also minimizes the amount of high frequency noise that is generated by the latch. An application using a plurality of such latch circuits in a parallel decoding ADC for use in an image sensor is given as an example.
Waves in space plasma dipole antenna subsystem
NASA Technical Reports Server (NTRS)
Thomson, Mark
1993-01-01
The Waves In Space Plasma (WISP) flight experiment requires a 50-meter-long deployable dipole antenna subsystem (DASS) to radiate radio frequencies from the STS Orbiter cargo bay. The transmissions are to excite outer ionospheric plasma between the dipole and a free-flying receiver (Spartan) for scientific purposes. This report describes the singular DASS design requirements and how the resulting design satisfies them. A jettison latch is described in some detail. The latch releases the antenna in case of any problems which might prevent the bay doors from closing for re-entry and landing of the Orbiter.
Waves in space plasma dipole antenna subsystem
NASA Astrophysics Data System (ADS)
Thomson, Mark
1993-05-01
The Waves In Space Plasma (WISP) flight experiment requires a 50-meter-long deployable dipole antenna subsystem (DASS) to radiate radio frequencies from the STS Orbiter cargo bay. The transmissions are to excite outer ionospheric plasma between the dipole and a free-flying receiver (Spartan) for scientific purposes. This report describes the singular DASS design requirements and how the resulting design satisfies them. A jettison latch is described in some detail. The latch releases the antenna in case of any problems which might prevent the bay doors from closing for re-entry and landing of the Orbiter.
77 FR 18137 - Airworthiness Directives; The Boeing Company Airplanes
Federal Register 2010, 2011, 2012, 2013, 2014
2012-03-27
...), latch pin migration, and broken latch pin fittings. This proposed AD would require various repetitive... cargo door latch mechanism and/or the lower sill structure. The migration of two or more latch pins and... determine if the bolt is broken; and checking the latch pin for migration and, if necessary, a detailed...
78 FR 4047 - Airworthiness Directives; The Boeing Company Airplanes
Federal Register 2010, 2011, 2012, 2013, 2014
2013-01-18
... migration of the latch pins of the main deck side cargo door (MDSCD). This AD requires various repetitive... broken retention bolts and the subsequent migration of the latch pins rather than by the broken latch pin... prompted by reports of broken and damaged latch pin retention bolts and subsequent migration of the latch...
Apparatus for and method of eliminating single event upsets in combinational logic
NASA Technical Reports Server (NTRS)
Gambles, Jody W. (Inventor); Hass, Kenneth J. (Inventor); Cameron, Kelly B. (Inventor)
2001-01-01
An apparatus for and method of eliminating single event upsets (or SEU) in combinational logic are used to prevent error propagation as a result of cosmic particle strikes to the combinational logic. The apparatus preferably includes a combinational logic block electrically coupled to a delay element, a latch and an output buffer. In operation, a signal from the combinational logic is electrically coupled to a first input of the latch. In addition, the signal is routed through the delay element to produce a delayed signal. The delayed signal is routed to a second input of the latch. The latch used in the apparatus for preventing SEU preferably includes latch outputs and a feature that the latch outputs will not change state unless both latch inputs are correct. For example, the latch outputs may not change state unless both latch inputs have the same logical state. When a cosmic particle strikes the combinational logic, a transient disturbance with a predetermined length may appear in the signal. However, a function of the delay element is to preferably provide a time delay greater than the length of the transient disturbance. Therefore, the transient disturbance will not reach both latch inputs simultaneously. As a result, the latch outputs will not permanently change state in error due to the transient disturbance. In addition, the output buffer preferably combines the latch outputs in such a way that the correct state is preserved at all times. Thus, combinational logic with protection from SEU is provided.
Self-Latching Piezocomposite Actuator
NASA Technical Reports Server (NTRS)
Wilkie, William K. (Inventor); Lynch, Christopher S. (Inventor); Bryant, Robert G. (Inventor)
2017-01-01
A self-latching piezocomposite actuator includes a plurality of shape memory ceramic fibers. The actuator can be latched by applying an electrical field to the shape memory ceramic fibers. The actuator remains in a latched state/shape after the electrical field is no longer present. A reverse polarity electric field may be applied to reset the actuator to its unlatched state/shape. Applied electric fields may be utilized to provide a plurality of latch states between the latched and unlatched states of the actuator. The self-latching piezocomposite actuator can be used for active/adaptive airfoils having variable camber, trim tabs, active/deformable engine inlets, adaptive or adjustable vortex generators, active optical components such as mirrors that change shapes, and other morphing structures.
49 CFR 571.206 - Standard No. 206; Door locks and door retention components.
Code of Federal Regulations, 2012 CFR
2012-10-01
... (GVWR) of 4,536 kg or less. S3. Definitions. Auxiliary Door Latch is a latch equipped with a fully... auxiliary door latch on each hinged door shall not disengage from the fully latched position when an inertia... hinged back door shall also not disengage from the fully latched position when an inertia load is applied...
49 CFR 571.206 - Standard No. 206; Door locks and door retention components.
Code of Federal Regulations, 2013 CFR
2013-10-01
... (GVWR) of 4,536 kg or less. S3. Definitions. Auxiliary Door Latch is a latch equipped with a fully... auxiliary door latch on each hinged door shall not disengage from the fully latched position when an inertia... hinged back door shall also not disengage from the fully latched position when an inertia load is applied...
49 CFR 571.206 - Standard No. 206; Door locks and door retention components.
Code of Federal Regulations, 2011 CFR
2011-10-01
... (GVWR) of 4,536 kg or less. S3. Definitions. Auxiliary Door Latch is a latch equipped with a fully... auxiliary door latch on each hinged door shall not disengage from the fully latched position when an inertia... hinged back door shall also not disengage from the fully latched position when an inertia load is applied...
49 CFR 571.206 - Standard No. 206; Door locks and door retention components.
Code of Federal Regulations, 2014 CFR
2014-10-01
... (GVWR) of 4,536 kg or less. S3. Definitions. Auxiliary Door Latch is a latch equipped with a fully... auxiliary door latch on each hinged door shall not disengage from the fully latched position when an inertia... hinged back door shall also not disengage from the fully latched position when an inertia load is applied...
DOT National Transportation Integrated Search
2012-04-01
This project investigated the usability of Lower Anchors and Tethers for CHildren (LATCH) hardware by measuring LATCH implementations in 98 2011 or 2010 model-year vehicles. ISO and SAE LATCH usability rating systems were used to assess all vehicles ...
NASA Technical Reports Server (NTRS)
Prokop, Norman F (Inventor)
2016-01-01
Analog circuits for detecting edges in pixel arrays are disclosed. A comparator may be configured to receive an all pass signal and a low pass signal for a pixel intensity in an array of pixels. A latch may be configured to receive a counter signal and a latching signal from the comparator. The comparator may be configured to send the latching signal to the latch when the all pass signal is below the low pass signal minus an offset. The latch may be configured to hold a last negative edge location when the latching signal is received from the comparator.
NASA Technical Reports Server (NTRS)
Prokop, Norman F (Inventor)
2015-01-01
Analog circuits for detecting edges in pixel arrays are disclosed. A comparator may be configured to receive an all pass signal and a low pass signal for a pixel intensity in an array of pixels. A latch may be configured to receive a counter signal and a latching signal from the comparator. The comparator may be configured to send the latching signal to the latch when the all pass signal is below the low pass signal minus an offset. The latch may be configured to hold a last negative edge location when the latching signal is received from the comparator.
High-powered automatic latching device
NASA Technical Reports Server (NTRS)
Cobin, J. C.; Rhodes, L. L.
1970-01-01
Latches automatically lock together two remotely controlled bodies when their triggers are engaged by the docking ring of the lesser body. Latches are disengaged by manual actuation of the handle of each latch through two complete cycles. Emergency locking by manual actuation is also provided.
49 CFR 236.710 - Block, latch.
Code of Federal Regulations, 2010 CFR
2010-10-01
... 49 Transportation 4 2010-10-01 2010-10-01 false Block, latch. 236.710 Section 236.710 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION... Block, latch. The lower extremity of a latch rod which engages with a square shoulder of the segment or...
Manual Override For Electromechanical Latch
NASA Technical Reports Server (NTRS)
Scott, Richard
1992-01-01
Override mechanism enables user to operate electromechanical latching mechanism manually if primary mechanism fails. Release/Engage Mechanism (REM) moves pin receivers to confine pins on object to be held. Clutch disengages electrically driven latch normally used. Used to latch and unlatch large, heavy objects from fixed support structure.
Gate drive latching circuit for an auxiliary resonant commutation circuit
NASA Technical Reports Server (NTRS)
Delgado, Eladio Clemente (Inventor); Kheraluwala, Mustansir Hussainy (Inventor)
1999-01-01
A gate drive latching circuit for an auxiliary resonant commutation circuit for a power switching inverter includes a current monitor circuit providing a current signal to a pair of analog comparators to implement latching of one of a pair of auxiliary switching devices which are used to provide commutation current for commutating switching inverters in the circuit. Each of the pair of comparators feeds a latching circuit which responds to an active one of the comparators for latching the associated gate drive circuit for one of the pair of auxiliary commutating switches. An initial firing signal is applied to each of the commutating switches to gate each into conduction and the resulting current is monitored to determine current direction and therefore the one of the switches which is carrying current. The comparator provides a latching signal to the one of the auxiliary power switches which is actually conducting current and latches that particular power switch into an on state for the duration of current through the device. The latching circuit is so designed that the only time one of the auxiliary switching devices can be latched on is during the duration of an initial firing command signal.
Steam separator latch assembly
Challberg, Roy C.; Kobsa, Irvin R.
1994-01-01
A latch assembly removably joins a steam separator assembly to a support flange disposed at a top end of a tubular shroud in a nuclear reactor pressure vessel. The assembly includes an annular head having a central portion for supporting the steam separator assembly thereon, and an annular head flange extending around a perimeter thereof for supporting the head to the support flange. A plurality of latches are circumferentially spaced apart around the head flange with each latch having a top end, a latch hook at a bottom end thereof, and a pivot support disposed at an intermediate portion therebetween and pivotally joined to the head flange. The latches are pivoted about the pivot supports for selectively engaging and disengaging the latch hooks with the support flange for fixedly joining the head to the shroud or for allowing removal thereof.
Steam separator latch assembly
Challberg, R.C.; Kobsa, I.R.
1994-02-01
A latch assembly removably joins a steam separator assembly to a support flange disposed at a top end of a tubular shroud in a nuclear reactor pressure vessel. The assembly includes an annular head having a central portion for supporting the steam separator assembly thereon, and an annular head flange extending around a perimeter thereof for supporting the head to the support flange. A plurality of latches are circumferentially spaced apart around the head flange with each latch having a top end, a latch hook at a bottom end thereof, and a pivot support disposed at an intermediate portion therebetween and pivotally joined to the head flange. The latches are pivoted about the pivot supports for selectively engaging and disengaging the latch hooks with the support flange for fixedly joining the head to the shroud or for allowing removal thereof. 12 figures.
Preloadable vector sensitive latch
NASA Technical Reports Server (NTRS)
Acres, William R. (Inventor)
1987-01-01
A preloadable vector-sensitive latch which automatically releases when the force vector from a latch memebr reaches a specified release angle is presented. In addition, it contains means to remove clearance between the latched members and to preload the latch to prevent separation at angles less than the specified release angle. The latch comprises a triangular main link, a free link connected between a first corner of the main link and a yoke member, a housing, and an actuator connected between the yoke member and the housing. A return spring bias means connects the main link to a portion of the housing. A second corner of the main link is slidably and pivotally connected to the housing via a slot in a web portion of the housing. The latch housing has a rigid docking ring alignable with a mating locking ring which is engageable by a locking roller journalled on the third corner of the triangular main link.
An advanced SEU tolerant latch based on error detection
NASA Astrophysics Data System (ADS)
Xu, Hui; Zhu, Jianwei; Lu, Xiaoping; Li, Jingzhao
2018-05-01
This paper proposes a latch that can mitigate SEUs via an error detection circuit. The error detection circuit is hardened by a C-element and a stacked PMOS. In the hold state, a particle strikes the latch or the error detection circuit may cause a fault logic state of the circuit. The error detection circuit can detect the upset node in the latch and the fault output will be corrected. The upset node in the error detection circuit can be corrected by the C-element. The power dissipation and propagation delay of the proposed latch are analyzed by HSPICE simulations. The proposed latch consumes about 77.5% less energy and 33.1% less propagation delay than the triple modular redundancy (TMR) latch. Simulation results demonstrate that the proposed latch can mitigate SEU effectively. Project supported by the National Natural Science Foundation of China (Nos. 61404001, 61306046), the Anhui Province University Natural Science Research Major Project (No. KJ2014ZD12), the Huainan Science and Technology Program (No. 2013A4011), and the National Natural Science Foundation of China (No. 61371025).
Two fault tolerant toggle-hook release
NASA Technical Reports Server (NTRS)
Graves, Thomas Joseph (Inventor); Brown, Christopher William (Inventor)
1991-01-01
A coupling device is disclosed which is mechanically two fault tolerant for release. The device comprises a fastener plate and fastener body, each of which is attachable to a different one of a pair of structures to be joined. The fastener plate and body are coupled by an elongate toggle mounted at one end in a socket on the fastener plate for universal pivotal movement thereon. The other end of the toggle is received in an opening in the fastener body and adapted for limited pivotal movement therein. The toggle is adapted to be restrained by three latch hooks arranged in symmetrical equiangular spacing about the axis of the toggle, each hook being mounted on the fastener body for pivotal movement between an unlatching non-contact position with respect to the toggle and a latching position in engagement with a latching surface of the toggle. The device includes releasable lock means for locking each latch hook in its latching position whereby the toggle couples the fastener plate to the fastener body and means for releasing the lock means to unlock each said latch hook from the latch position whereby the unlocking of at least one of the latch hooks from its latching position results in the decoupling of the fastener plate from the fastener body.
Outcomes of Video-Assisted Teaching for Latching in Postpartum Women: A Randomized Controlled Trial.
Sroiwatana, Suttikamon; Puapornpong, Pawin
2018-04-25
Latching is an important process of breastfeeding and should be taught and practiced by the postpartum mother. The objective is to compare latching outcomes between video-assisted and routine teaching methods among postpartum women. A randomized controlled trial was conducted. Postpartum women who had deliveries without complications were randomized into two groups: 14 cases in the video-assisted teaching group and 14 cases in a routine teaching group. In the first group, the mothers were taught breastfeeding benefits, latching methods, and breastfeeding positions and practiced breastfeeding in a controlled setting for a 30-minute period and watched a 6-minute video with consistent content. In the second group, the mothers were taught a normal 30-minute period and then practiced breastfeeding. In both groups, Latching on, Audible swallowing, the Type of nipples, Comfort, and Help (LATCH) scores were assessed at 24-32 and 48-56 hours after the breastfeeding teaching modals. Demographic data and LATCH scores were collected and analyzed. There were no statistically significant differences in the mothers' ages, occupations, marital status, religion, education, income, infants' gestational age, body mass index, nipple length, route of delivery, and time to first latching between the video-assisted and routine breastfeeding teaching groups. First and second LATCH score assessments had shown no significant differences between both breastfeeding teaching groups. The video-assisted breastfeeding teaching did not improve latching outcomes when it was compared with routine teaching.
Using granular film to suppress charge leakage in a single-electron latch.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Orlov, A. O.; Luo, X.; Yadavalli, K. K.
2008-01-01
A single-electron latch is a device that can be used as a building block for quantum-dot cellular automata circuits. It consists of three nanoscale metal 'dots' connected in series by tunnel junctions; charging of the dots is controlled by three electrostatic gates. One very important feature of a single-electron latch is its ability to store ('latch') information represented by the location of a single electron within the three dots. To obtain latching, the undesirable leakage of charge during the retention time must be suppressed. Previously, to achieve this goal, multiple tunnel junctions were used to connect the three dots. However,more » this method of charge leakage suppression requires an additional compensation of the background charges affecting each parasitic dot in the array of junctions. We report a single-electron latch where a granular metal film is used to fabricate the middle dot in the latch which concurrently acts as a charge leakage suppressor. This latch has no parasitic dots, therefore the background charge compensation procedure is greatly simplified. We discuss the origins of charge leakage suppression and possible applications of granular metal dots for various single-electron circuits.« less
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.
CAM controlled retractable door latch
NASA Technical Reports Server (NTRS)
Carsley, R. B. (Inventor)
1982-01-01
A latching mechanism in which there is linear movement and rotational movement is described. The umbilical doors of the space shuttle orbiter are required to be open during vehicle launch. After the external tank is released, the doors are closed. Presently, the device for maintaining the doors in an open position is mounted on the external tank and therefore has a single mission life. The latching mechanism of the invention is mounted in the orbiter and therefore is returned and has multimission capability. The latching mechanism is comprised of a pair of concentric nested, cylindrical cams and motors to actuate the cams, and latch pin all contained within a cover mounted on a support bracket carried by the substructure. A shaft having a latch pin is mounted inside the inner cylindrical cam.
Evolution of the IBDM Structural Latch Development into a Generic Simplified Design
NASA Technical Reports Server (NTRS)
DeVriendt, K.; Dittmer, H.; Vrancken, D.; Urmston, P.; Gracia, O.
2010-01-01
This paper presents the evolution in the development of the structural latch for the International Berthing Docking Mechanism (IBDM, see Figure 1). It reports on the lessons learned since completion of the test program on the engineering development unit of the first generation latching system in 2007. The initial latch design has been through a second generation concept in 2008, and now evolved into a third generation of this mechanism. Functional and structural testing on the latest latch hardware has recently been completed with good results. The IBDM latching system will provide the structural connection between two mated space vehicles after berthing or docking. The mechanism guarantees that the interface seals become compressed to form a leak-tight pressure system that creates a passageway for the astronauts.
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)
Minimal Power Latch for Single-Slope ADCs
NASA Technical Reports Server (NTRS)
Hancock, Bruce R.
2013-01-01
Column-parallel analog-to-digital converters (ADCs) for imagers involve simultaneous operation of many ADCs. Single-slope ADCs are well adapted to this use because of their simplicity. Each ADC contains a comparator, comparing its input signal level to an increasing reference signal (ramp). When the ramp is equal to the input, the comparator triggers a latch that captures an encoded counter value (code). Knowing the captured code, the ramp value and hence the input signal are determined. In a column-parallel ADC, each column contains only the comparator and the latches; the ramp and code generation are shared. In conventional latch or flip-flop circuits, there is an input stage that tracks the input signal, and this stage consumes switching current every time the input changes. With many columns, many bits, and high code rates, this switching current can be substantial. It will also generate noise that may corrupt the analog signals. A latch was designed that does not track the input, and consumes power only at the instant of latching the data value. The circuit consists of two S-R (set-reset) latches, gated by the comparator. One is set by high data values and the other by low data values. The latches are cross-coupled so that the first one to set blocks the other. In order that the input data not need an inversion, which would consume power, the two latches are made in complementary polarity. This requires complementary gates from the comparator, instead of complementary data values, but the comparator only triggers once per conversion, and usually has complementary outputs to begin with. An efficient CMOS (complementary metal oxide semiconductor) implementation of this circuit is shown in the figure, where C is the comparator output, D is the data (code), and Q0 and Q1 are the outputs indicating the capture of a zero or one value. The latch for Q0 has a negative-true set signal and output, and is implemented using OR-AND-INVERT logic, while the latch for Q1 uses positive- true signals and is implemented using AND-OR-INVERT logic. In this implementation, both latches are cleared when the comparator is reset. Two redundant transistors are removed from the reset side of each latch, making for a compact layout. CMOS imagers with column-parallel ADCs have demonstrated high performance for remote sensing applications. With this latch circuit, the power consumption and noise can be further reduced. This innovation can be used in CMOS imagers and very-low-power electronics
International Space Station alpha remote manipulator system workstation controls test report
NASA Astrophysics Data System (ADS)
Ehrenstrom, William A.; Swaney, Colin; Forrester, Patrick
1994-05-01
Previous development testing for the space station remote manipulator system workstation controls determined the need for hardware controls for the emergency stop, brakes on/off, and some camera functions. This report documents the results of an evaluation to further determine control implementation requirements, requested by the Canadian Space Agency (CSA), to close outstanding review item discrepancies. This test was conducted at the Johnson Space Center's Space Station Mockup and Trainer Facility in Houston, Texas, with nine NASA astronauts and one CSA astronaut as operators. This test evaluated camera iris and focus, back-up drive, latching end effector release, and autosequence controls using several types of hardware and software implementations. Recommendations resulting from the testing included providing guarded hardware buttons to prevent accidental actuation, providing autosequence controls and back-up drive controls on a dedicated hardware control panel, and that 'latch on/latch off', or on-screen software, controls not be considered. Generally, the operators preferred hardware controls although other control implementations were acceptable. The results of this evaluation will be used along with further testing to define specific requirements for the workstation design.
International Space Station alpha remote manipulator system workstation controls test report
NASA Technical Reports Server (NTRS)
Ehrenstrom, William A.; Swaney, Colin; Forrester, Patrick
1994-01-01
Previous development testing for the space station remote manipulator system workstation controls determined the need for hardware controls for the emergency stop, brakes on/off, and some camera functions. This report documents the results of an evaluation to further determine control implementation requirements, requested by the Canadian Space Agency (CSA), to close outstanding review item discrepancies. This test was conducted at the Johnson Space Center's Space Station Mockup and Trainer Facility in Houston, Texas, with nine NASA astronauts and one CSA astronaut as operators. This test evaluated camera iris and focus, back-up drive, latching end effector release, and autosequence controls using several types of hardware and software implementations. Recommendations resulting from the testing included providing guarded hardware buttons to prevent accidental actuation, providing autosequence controls and back-up drive controls on a dedicated hardware control panel, and that 'latch on/latch off', or on-screen software, controls not be considered. Generally, the operators preferred hardware controls although other control implementations were acceptable. The results of this evaluation will be used along with further testing to define specific requirements for the workstation design.
Interplanetary Particle Environment. Proceedings of a Conference
NASA Technical Reports Server (NTRS)
Feynman, Joan (Editor); Gabriel, Stephen (Editor)
1988-01-01
A workshop entitled the Interplanetary Charged Particle Environment was held at the Jet Propulsion Laboratory (JPL) on March 16 and 17, 1987. The purpose of the Workshop was to define the environment that will be seen by spacecraft operating in the 1990s. It focused on those particles that are involved in single event upset, latch-up, total dose and displacement damage in spacecraft microelectronic parts. Several problems specific to Magellan were also discussed because of the sensitivity of some electronic parts to single-event phenomena. Scientists and engineers representing over a dozen institutions took part in the meeting. The workshop consisted of two major activities, reviews of the current state of knowledge and the formation of working groups and the drafting of their reports.
78 FR 21576 - Airworthiness Directives; The Boeing Company Airplanes
Federal Register 2010, 2011, 2012, 2013, 2014
2013-04-11
... with Inspection Condition 5: Repeat the high frequency eddy current or magnetic particle inspection to... latch pins for discrepancies; and an HFEC or magnetic particle inspection of cam latch 1 and cam latch 2...
NASA Technical Reports Server (NTRS)
Ulrich, G. W. (Inventor)
1975-01-01
A latching device is suited for use in establishing a substantially motionless connection between a stationary receiver and a movable latching mechanism. The latching mechanism includes a pivotally supported restraining hook continuously urged into a capturing relationship with the receiver, characterized by a spring-biased pawl having a plurality of aligned teeth. The teeth are seated in the surface of the throat of the hook and positionable into restraining engagement with a rigid restraining shoulder projected from the receiver.
Soil sampling device with latch assembly having a variable circumferential shape
Meyer, R.D.
1996-12-24
The invention relates to an improved sampler which can be operated in any orientation. The design features a positive gripping of the operating rod in a manner to reduce point loads so as to reduce any possibility of jamming of the rod on a retraction stroke until such time as it is positively retained in the fully withdrawn position. In the preferred embodiment, a pair of mating cylindrical latch pieces, held together by a circumferential spring, are used for positive actuation. The inner rod has an angular cut-out which provides the base for the latch when aligned with the latch. A release fixture can be used to free the latch from the cone rod after actuation. The latches are formed in such a manner as they may support themselves within the housing of the sampler until they engage the operating rod. 11 figs.
Soil sampling device with latch assembly having a variable circumferential shape
Meyer, Robert D.
1996-01-01
The invention relates to an improved sampler which can be operated in any orientation. The design features a positive gripping of the operating rod in a manner to reduce point loads so as to reduce any possibility of jamming of the rod on a retraction stroke until such time as it is positively retained in the fully withdrawn position. In the preferred embodiment, a pair of mating cylindrical latch pieces, held together by a circumferential spring, are used for positive actuation. The inner rod has an angular cut-out which provides the base for the latch when aligned with the latch. A release fixture can be used to free the latch from the cone rod after actuation. The latches are formed in such a manner as they may support themselves within the housing of the sampler until they engage the operating rod.
NASA Technical Reports Server (NTRS)
Gibson, John C. (Inventor); Calvert, John A. (Inventor); Nesmith, Malcolm F. (Inventor); Cloyd, Richard A. (Inventor)
1986-01-01
A self-latching jaw assembly is described which includes a pair of jaws for latching a fitting of an associated structure such as the keel fitting of a space telescope. The jaw assembly automatically locates the fitting received on a positioning pedestal and latches it in its original location on the pedestal without need of precision alignment. The first jaw is actuated and moved to the right whereupon a reciprocating plunger, extended from the nose of the jaw senses the hub of the spool. A jaw position responsive switch is then actuated to terminate the drive motor of the jaw. The astronaut will then actuate the drive motor of the jaw and the jaw will move to the left, whereupon the standoff will engage the face of the jaw in a latching position. In the latching position, the noses of the jaws will be under the flanges of the spool.
Characterization of an Autonomous Non-Volatile Ferroelectric Memory Latch
NASA Technical Reports Server (NTRS)
John, Caroline S.; MacLeod, Todd C.; Evans, Joe; Ho, Fat D.
2011-01-01
We present the electrical characterization of an autonomous non-volatile ferroelectric memory latch using the principle that when an electric field is applied to a ferroelectriccapacitor,the positive and negative remnant polarization charge states of the capacitor are denoted as either data 0 or data 1. The properties of the ferroelectric material to store an electric polarization in the absence of an electric field make the device non-volatile. Further the memory latch is autonomous as it operates with the ground, power and output node connections, without any externally clocked control line. The unique quality of this latch circuit is that it can be written when powered off. The advantages of this latch over flash memories are: a) It offers unlimited reads/writes b) works on symmetrical read/write cycles. c) The latch is asynchronous. The circuit was initially developed by Radiant Technologies Inc., Albuquerque, New Mexico.
R AND D 100 EARLYBIRD AWARD ENTRY
DOE Office of Scientific and Technical Information (OSTI.GOV)
Dugan, J; Debbie Chapman, D
2007-01-30
The Smart Latch{trademark} is an electronically enhanced door lockset device for industrial and consumer applications, which uses existing neural network technology to analyze the sequence, timing, and acoustic signatures associated with lockset functions and provides immediate indication of failure to correctly lock and latch. It essentially ''listens'' to and learns the sequences and acoustic signatures associated with lockset function and latching. When triggered by specific door activity the Smart Latch{trademark} begins analyzing sequences, frequencies and other parameters. With a satisfactory outcome the device provides positive feedback (e.g. visual and/or audible) and returns to a ''sleep'' state awaiting the next activity.more » If any part of the normal door operation, including latching and length of time, are incorrect various alarm signals can be generated. With electronics and 5+ year battery integrated, the device is simple to install and transparent to the user. Because the device uses proven voice recognition algorithms, it could meet or exceed the performance of the human ear in detecting the unique and complex acoustic signature associated with a properly operating and secured door. Unlike existing technologies, such as limit switches, it is not easily spoofed or defeated and has a high level of immunity to interference. The Smart Latch{trademark} technology can be integrated into existing lockset and door hardware designs, including both low price consumer products and high end electronic/cipher locks. The concept and design are based on a simple security industry adage: ''It isn't locked if it isn't latched''. Even the most elaborate and robust security barriers are of little use if the locking and latching mechanisms are not properly functioning and engaged. Smart Latch{trademark} provides automatic verification of the first and most important step in facility security: Close and properly latch doors and barriers. It is a compelling product for households with children, elderly, or high traffic areas such as an office where a properly closed and latched door is essential for security and safety. In an age of ever increasing security concerns and limited human resources, Smart Latch{trademark} can be a significant addition to the $20 billion plus industrial and consumer lockset market. The Smart Latch{trademark} is unique because: (1) as an inexpensive, battery powered, stand-alone device or as integrated into any standard consumer lock set, the device uses neural network technology to analyze the acoustic signatures associated with normal door operation and generates an alert if a door is not latched correctly and within a set amount of time. (2) It is not easily spoofed or defeated. (3) Installation, setup, and use are simple.« less
Centerline latch tool for contingency orbiter door closure
NASA Technical Reports Server (NTRS)
Trevino, R. C.
1982-01-01
The centerline latch tool was designed and developed as an EVA manual backup device for latching the Space Shuttle Orbiter's payload bay doors for reentry in case of a failure of the existing centerline latches to operate properly. The tool was designed to satisfy a wide variety of structural, mechanical, and EVA requirements. It provides a load path for forces on the payload bay doors during reentry. Since the tool would be used by an EVA crewmember, control, handgrips, operating forces, and procedures must be within the capabilities of a partially restrained, suited crewmember in a zero-gravity environment. The centerline latch tool described was designed, developed, and tested to meet these requirements.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Frederickson, James R.; Harper, William H.; Perez, Raymond
1986-01-01
A latch assembly for releasably securing an article in the form of a canister within a container housing. The assembly includes a cam pivotally mounted on the housing wall and biased into the housing interior. The cam is urged into a disabled position by the canister as it enters the housing and a latch release plate maintains the cam disabled when the canister is properly seated in the housing. Upon displacement of the release plate, the cam snaps into latching engagement against the canister for securing the same within the housing.
Frederickson, J.R.; Harper, W.H.; Perez, R.
1984-08-17
A latch assembly for releasably securing an article in the form of a canister within a container housing. The assembly includes a cam pivotally mounted on the housing wall and biased into the housing interior. The cam is urged into a disabled position by the canister as it enters the housing and a latch release plate maintains the cam disabled when the canister is properly seated in the housing. Upon displacement of the release plate, the cam snaps into latching engagement against the canister for securing the same within the housing. 2 figs.
Design of mechanisms to lock/latch systems under rotational or translational motion
NASA Technical Reports Server (NTRS)
Billimoria, R. P.
1976-01-01
Bodies/systems need to be stopped and locked/latched at the end of their path. Some examples of these systems in the aerospace industry (including launch vehicle, spacecraft, and the ground support equipment) are the command module access arm, service arms, docking module of the ASTP and the orbiter access arm for the space shuttle. Two major aspects are covered: (1) various methods of latching and (2) selection of the optimum method for latching, depending on the application and the design requirement criteria.
77 FR 29212 - Airworthiness Directives; The Boeing Company Airplanes
Federal Register 2010, 2011, 2012, 2013, 2014
2012-05-17
... Company Model 777 airplanes. This AD was prompted by reports of fractured and missing latch pin retention... inspections for fractured or missing latch pin retention bolts, replacement of existing titanium bolts with... AD to detect and correct fractured and missing latch pin retention bolts, which could result in...
A Foot Operated Timeout Room Door Latch.
ERIC Educational Resources Information Center
Foxx, R. M.; And Others
1982-01-01
This report describes the design and implementation of a foot operated timeout room door latch that permits staff members to maintain a misbehaving retarded individual in timeout without locking the door. Use of the latch also frees the staff member involved to record behavioral observations or reinforce appropriate behavior. (Author)
ERIC Educational Resources Information Center
Landsberg, Hans H.
This paper offers a fresh perspective on causes of and solutions to environmental problems, and would be useful as an initiator of classroom discussions. The author argues that in our pursuit of a society based on environmentally sound principles, we have perhaps misidentified the villains, and have latched into solutions that may be either naive,…
Apparatus for retaining and releasing a payload
NASA Technical Reports Server (NTRS)
Carrier, Alain (Inventor); Cobb, Bruce (Inventor)
2000-01-01
An apparatus for latching an object, such as a payload for a space vehicle, includes an expandible latch which is shifted between a relaxed open condition and a flexed closed condition by actuation of a pair of temperature-responsive members, such as shaped memory alloy (SMA) coil springs. One of the two temperature-responsive members biases an actuator into a first position that allows the expandible latch to open. The other SMA member biases the actuator in the opposite position to close the expandible latch. Heating the appropriate SMA member causes the actuator to move from one position to the other position. In the preferred embodiment, no power is required to maintain the actuator in either position once the position has been established. For example, the actuator may have a rest position that allows the expandible latch to remain open when the two SMA members are cooled and allowed to reach an equilibrium condition with respect to applied force to the actuator. A detent-and-ball arrangement may be used to maintain the position of the actuator after the expandible latch has been closed.
Cassette for handling banknotes or the like
Lundblad, Leif
1981-08-11
A cassette for banknotes and like valuable articles is provided with a displaceable lid (6) and locking means (10) for latching the lid of the cassette when the cassette is located outside a housing (25) in which it is intended to be placed. An operating means (8) is arranged to co-act with the locking means and with a latching element (15). The latching element is arranged to be released in dependence upon a pre-set program. A signal circuit is arranged to send a code signal to a detector circuit (23) when electrical contact elements on the cassette and the housing co-act with one another, which detector circuit, when the signal coincides with the signal program in the detector circuit, causes a signal to be sent for moving the latching means to a non-latching position.
Latching mechanism for deployable/re-stowable columns useful in satellite construction
NASA Technical Reports Server (NTRS)
Ahl, E. L., Jr. (Inventor)
1986-01-01
A column longeron latch assembly provides the securing mechanism for the deployable, telescoping column of a hoop/column antenna. The column is an open lattice structure with three longerons disposed 120 deg apart as the principle load bearing member. The column is deployed from a pair of eleven nested bays disposed on opposite sides of a center section under the influence of a motor-cable-pulley system. The longeron latch is a four bar linkage mechanism using the over-center principle for automatically locking the longeron sections into position during deployment. The latch is unlocked when the antenna is to be restowed. A spring pack disposed in the end of each longeron serves to absorb stress forces on the deployed column through the cam head piston and abutting latch from an adjacent longeron.
Vawter, G Allen [Corrales, NM
2010-08-31
An optical data latch is formed on a substrate from a pair of optical logic gates in a cross-coupled arrangement in which optical waveguides are used to couple an output of each gate to an photodetector input of the other gate. This provides an optical bi-stability which can be used to store a bit of optical information in the latch. Each optical logic gate, which can be an optical NOT gate (i.e. an optical inverter) or an optical NOR gate, includes a waveguide photodetector electrically connected in series with a waveguide electroabsorption modulator. The optical data latch can be formed on a III-V compound semiconductor substrate (e.g. an InP or GaAs substrate) from III-V compound semiconductor layers. A number of optical data latches can be cascaded to form a clocked optical data shift register.
High performance static latches with complete single event upset immunity
Corbett, Wayne T.; Weaver, Harry T.
1994-01-01
An asymmetric response latch providing immunity to single event upset without loss of speed. The latch has cross-coupled inverters having a hardened logic state and a soft state, wherein the logic state of the first inverter can only be changed when the voltage on the coupling node of that inverter is low and the logic state of the second inverter can only be changed when the coupling of that inverter is high. One of more of the asymmetric response latches may be configured into a memory cell having complete immunity, which protects information rather than logic states.
Latch Key: Developing Child Care Programs Through Community Education.
ERIC Educational Resources Information Center
Cramer, James P.; And Others
This guide to the Latch Key program for after-school day care explores rationale and methods for developing Latch Key programs in the public schools to provide low cost after-school care for children (grades 1-6) of working or student parents. (Some programs have been provided for kindergarten children and some have been expanded to full time…
Latching relay switch assembly
Duimstra, Frederick A.
1991-01-01
A latching relay switch assembly which includes a coil section and a switch or contact section. The coil section includes at least one permanent magnet and at least one electromagnet. The respective sections are, generally, arranged in separate locations or cavities in the assembly. The switch is latched by a permanent magnet assembly and selectively switched by an overriding electromagnetic assembly.
75 FR 61987 - Airworthiness Directives; Bombardier, Inc. Model DHC-8 Airplanes
Federal Register 2010, 2011, 2012, 2013, 2014
2010-10-07
... the access panel involving the use of excessive force. Failure of the latch assembly can result in the... closure of the access panel involving the use of excessive force. Failure of the latch assembly can result... panel involving the use of excessive force. Failure of the latch assembly can result in the access panel...
75 FR 38064 - Airworthiness Directives; Bombardier, Inc. Model DHC-8 Airplanes
Federal Register 2010, 2011, 2012, 2013, 2014
2010-07-01
... involving the use of excessive force. Failure of the latch assembly can result in the access panel being... excessive force. Failure of the latch assembly can result in the access panel being jammed in the closed... panel involving the use of excessive force. Failure of the latch assembly can result in the access panel...
77 FR 19055 - Morgan Olson, LLC, Receipt of Petition for Decision of Inconsequential Noncompliance
Federal Register 2010, 2011, 2012, 2013, 2014
2012-03-29
... noncompliance is that the affected vehicles do not contain a primary door latch system or door closure warning... for either a primary door latch system or door closure warning system applied only to its vehicles... latched position. Nor are these vehicles equipped with a door closure warning system. Rule text: Paragraph...
Quick-Connect, Self-Alining Latch
NASA Technical Reports Server (NTRS)
Burns, G. C.; Williams, E. J.
1983-01-01
Sturdy latch tolerates 10 degrees of angular mismatch in joining structural elements. Hexagonal passive plate nests in active plate, guided by capture plates and alinement keys and grooves. Center hole in both active and passive plates is 1 meter in diameter. Latch has possible uses a pipe joint, connector for parts of portable structures, and fitting for marine risers on offshore drilling rigs.
Development of a high force thermal latch
NASA Technical Reports Server (NTRS)
Nygren, William D.
1995-01-01
This paper describes the preliminary development of a high force thermal latch (HFTL). The HFTL has one moving part which is restrained in the latched position by a low melting temperature or fusible metal alloy. When heated the fusible alloy flows to a receiving chamber and in so doing at first releases the tension load in the latch bolt and later releases the bolt itself. The HFTL can be used in place of pyrotechnically activated spacecraft release devices in those instances where the elimination of both pyrotechnic shock-loading and rapid strain-energy release take precedence over the near instantaneous release offered by ordnance initiated devices.
High performance static latches with complete single event upset immunity
Corbett, W.T.; Weaver, H.T.
1994-04-26
An asymmetric response latch providing immunity to single event upset without loss of speed is described. The latch has cross-coupled inverters having a hardened logic state and a soft state, wherein the logic state of the first inverter can only be changed when the voltage on the coupling node of that inverter is low and the logic state of the second inverter can only be changed when the coupling of that inverter is high. One of more of the asymmetric response latches may be configured into a memory cell having complete immunity, which protects information rather than logic states. 5 figures.
NASA Technical Reports Server (NTRS)
Wesselski, Clarence J. (Inventor); Nagy, Kornel (Inventor)
1992-01-01
A latching device is disclosed which is lever operated sequentially to actuate a set of collet fingers to provide a radial expansion and to actuate a force mechanism to provide a compressive gripping force for attaching first and second devices to one another. The latching device includes a body member having elongated collet fingers which, in a deactuated condition, is insertable through bores on the first and second devices so that gripping terminal portions on the collet fingers are proximate to the end of the bore of the first device while a spring assembly on the body member is located proximate to the outer surface of a second device. A lever is rotatable through 90 deg to move a latching rod to sequentially actuate and expand collet fingers and to actuate the spring assembly by compressing it. During the first 30 deg of movement of the lever, the collet fingers are actuated by the latching rod to provide a radial expansion and during the last 60 deg of movement of the lever, the spring assembly acts as a force mechanism and is actuated to develop a compressive latching force on the devices. The latching rod and lever are connected by a camming mechanism. The amount of spring force in the spring assembly can be adjusted; the body member can be permanently attached by a telescoping assembly to one of the devices; and the structure can be used as a pulling device for removing annular bearings or the like from blind bores.
Remote tong/tool latch and storage bracket for an advanced servo-manipulator
Nicholson, John R.
1990-01-01
An arrangement for stowing releasable end effectors for manipulator arms wherein the end effector includes a releasable latch mechanism for connecting the end effector to the manipulator arm, and a storage holder is provided which includes an arrangement for actuating the latch mechanism as the end effector is moved into and out of the holder by the action of the manipulator arm.
Slide release mechanism. [for space shuttle orbiter/external tank connection device
NASA Technical Reports Server (NTRS)
Bunker, J. W.; Ritchie, R. S. (Inventor)
1985-01-01
A releasable support device is described which is comprised of a hollow body with a sleeve extending transversely there-through for receiving the end of a support shank. A slider-latch, optionally lubricated, extends through side recesses in the sleeve to straddle the shank, respectively, in latched and released positions. The slider-latch is slid from its latched to its unlatched position by a pressure squib whereupon a spring or other pressure means pushes the shank out of the sleeve. At the same time, a follower element is lodged in and closed the hole in the body wall from which the shank was discharged. The mechanism was designed for the shuttle orbiter/external tank connection device.
Remote tong/tool latch and storage bracket for an advanced servo-manipulator
DOE Office of Scientific and Technical Information (OSTI.GOV)
Nicholson, J.R.
1990-04-03
An arrangement is described for stowing releasable end effectors for manipulator arms wherein the end effector includes a releasable latch mechanism for connecting the end effector to the manipulator arm, and a storage holder is provided which includes an arrangement for actuating the latch mechanism as the end effector is moved into and out of the holder by the action of the manipulator arm. 7 figs.
Design and analysis of a keel latch for use on the Hubble Space Telescope
NASA Technical Reports Server (NTRS)
Calvert, John; Stinson, Melanie
1986-01-01
The mechanical design of the keel latch is discussed, as well as the stress analysis of the keel latch. Background information; mechanical design requirements; some of the initial design considerations; the design considerations that led to the selection of the final design; the mechanics of the final design; testing that has been and will be accomplished to verify that design requirements have been met; and future tests are discussed.
NASA Technical Reports Server (NTRS)
Smith, James T.
2008-01-01
The development of the in-house Miniaturized Double Latching Solenoid Valve, or Microvalve, for the Gas Processing System (GPS) of the Sample Analysis at Mars (SAM) instrument suite is described. The Microvalve is a double latching solenoid valve that actuates a pintle shaft axially to hermetically seal an orifice. The key requirements and the design innovations implemented to meet them are described.
NASA Technical Reports Server (NTRS)
Blaes, B. R.; Soli, G. A.; Buehler, M. G.
1991-01-01
A methodology is described for predicting the SEU susceptibility of a standard-cell D-latch using an alpha-particle sensitive SRAM, SPICE critical charge simulation results, and alpha-particle interaction physics. Measurements were made on a 1.6-micron n-well CMOS 4-kb test SRAM irradiated with an Am-241 alpha-particle source. A collection depth of 6.09 micron was determined using these results and TRIM computer code. Using this collection depth and SPICE derived critical charge results on the latch design, an LET threshold of 34 MeV sq cm/mg was predicted. Heavy ion tests were then performed on the latch and an LET threshold of 41 MeV sq cm/mg was determined.
An overview of the neuron ring model
NASA Technical Reports Server (NTRS)
Taber, Rod
1991-01-01
The Neuron Ring model employs an avalanche structure with two important distinctions at the neuron level. Each neuron has two memory latches; one traps maximum neuronal activation during pattern presentation, and the other records the time of latch content change. The latches filter short term memory. In the process, they preserve length 1 snapshots of activation theory history. The model finds utility in pattern classification. Its synaptic weights are first conditioned with sample spectra. The model then receives a test or unknown signal. The objective is to identify the sample closest to the test signal. Class decision follows complete presentation of the test data. The decision maker relies exclusively on the latch contents. Presented here is an overview of the Neuron Ring at the seminar level.
Early breastfeeding problems: A mixed method study of mothers' experiences.
Feenstra, Maria Monberg; Jørgine Kirkeby, Mette; Thygesen, Marianne; Danbjørg, Dorthe B; Kronborg, Hanne
2018-06-01
Breastfeeding problems are common and associated with early cessation. Still length of postpartum hospital stay has been reduced. This leaves new mothers to establish breastfeeding at home with less support from health care professionals. The objective was to explore mothers' perspectives on when breastfeeding problems were the most challenging and prominent early postnatal. The aim was also to identify possible factors associated with the breastfeeding problems. In a cross-sectional study, a mixed method approach was used to analyse postal survey data from 1437 mothers with full term singleton infants. Content analysis was used to analyse mothers' open text descriptions of their most challenging breastfeeding problem. Multiple logistic regression was used to calculate odds ratios for early breastfeeding problems according to sociodemographic- and psychosocial factors. Up to 40% of the mothers had experienced early breastfeeding problems. The problems were associated with the mother, the infant and to lack of support from health care professionals. Most prominent problems were infant's inability to latch on (40%) and mothers having sore, wounded and cracked nipples (38%). Pain often occurred when experiencing breastfeeding problems. Factors associated with the problems were primiparity, lower self-efficacy and lower self-perceived knowledge of breastfeeding. Mothers with no or short education reported less frequently breastfeeding problems. Breastfeeding problems occurred frequently in the early postnatal period and often caused breastfeeding to be painful. Health care professionals should prepare mothers to deal with possible breastfeeding problems. New support options should be reviewed in an early postnatal discharge setting. Copyright © 2018 Elsevier B.V. All rights reserved.
Multi-function magnetic jack control drive mechanism
Bollinger, L.R.; Crawford, D.C.
1983-10-06
A multi-function magnetic jack control drive mechanism for controlling a nuclear reactor is provided. The mechanism includes an elongate pressure housing in which a plurality of closely spaced drive rods are located. Each drive rod is connected to a rod which is insertable in the reactor core. An electromechanical stationary latch device is provided which is actuatable to hold each drive rod stationary with respect to the pressure housing. An electromechanical movable latch device is also provided for each one of the drive rods. Each movable latch device is provided with a base and is actuatable to hold a respective drive rod stationary with respect to the base. An electromechanical lift device is further provided for each base which is actuatable for moving a respective base longitudinally along the pressure housing. In this manner, one or more drive rods can be moved in the pressure housing by sequentially and repetitively operating the electromechanical devices. Preferably, each latch device includes a pair of opposed latches which grip teeth located on the respective drive rod. Two, three, or four drive rods can be located symmetrically about the longitudinal axis of the pressure housing.
Multi-function magnetic jack control drive mechanism
Bollinger, Lawrence R.; Crawford, Donald C.
1986-01-01
A multi-function magnetic jack control drive mechanism for controlling a nuclear reactor is provided. The mechanism includes an elongate pressure housing in which a plurality of closely spaced drive rods are located. Each drive rod is connected to a rod which is insertable in the reactor core. An electromechanical stationary latch device is provided which is actuatable to hold each drive rod stationary with respect to the pressure housing. An electromechanical movable latch device is also provided for each one of the drive rods. Each movable latch device is provided with a base and is actuatable to hold a respective drive rod stationary with respect to the base. An electromechanical lift device is further provided for each base which is actuatable for moving a respective base longitudinally along the pressure housing. In this manner, one or more drive rods can be moved in the pressure housing by sequentially and repetitively operating the electromechanical devices. Preferably, each latch device includes a pair of opposed latches which grip teeth located on the respective drive rod. Two, three, or four drive rods can be located symmetrically about the longitudinal axis of the pressure housing.
Electrically controlled optical latch and switch requires less current
NASA Technical Reports Server (NTRS)
Pieczonka, W. A.; Roy, M. M.; Yeh, T. H.
1966-01-01
Electrically controlled optical latch consists of a sensitive phototransistor and a solid-state light source. This design requires less current to activate an optically activated switch than in prior art.
Misuse study of latch attachment: a series of frontal sled tests.
Menon, Rajiv; Ghati, Yoganand
2007-01-01
This study was initiated to quantify the effects of the misuse in LATCH lower webbing. In the short period since the implementation of the LATCH system several cases of potential misuses have been reported. A series of sled tests in frontal impact mode were conducted with various misuse conditions (loose attachment of LATCH lower webbing, misrouting of LATCH lower webbing and child seat back inclination) for both forward and rearward facing child safety seats (FFCSS and RFCSS). Results from these tests are compared and discussed with that of the standard test with no misuse and showed that as the slack in the lower LATCH webbing increased, ATD injury measures exceeded the limits. The FFCSS tests in the reclined condition yielded lower injury values for all except the chest G's when compared to the standard upright test. In the misrouting tests the ATD kinematics depended on the routing pivot point, the lower the pivot point the better the ATD kinematics. Similar findings were also observed in the RFCSS tests. The use of top tether with the FFCSS substantially improved the performance of the Hybrid III 3 year old ATD in spite of misuse conditions and the injury values were lower than the corresponding tests with no top tether. The effective reduction was 37% in the HIC values, 6% in the chest G's, 30% in the head excursion, 22 % in the knee excursion and finally 37 % reduction in the Nij values.
Fuel transfer tube quick opening hatch
DOE Office of Scientific and Technical Information (OSTI.GOV)
Meuschke, R. E.; Sherwood, D. G.; Silverblatt, B. L.
1985-05-28
A quick opening hatch for use on a transfer tube of a nuclear reactor plant that is adapted to replace the conventional hatch on the transfer tube. A locking ring is provided with a plurality of screw openings that is adapted for connection to the transfer tube, and a hatch cover fitably received within the locking ring for closing-off the transfer tube. To lock the cover to the ring, latches are movably connected with the cover for locking engagement with the locking ring, and a sprocket with a plurality of crank arms is movably connected with the cover and themore » latches for movement thereof into locking engagement with a latch housing on the locking ring for locking the cover to the ring and out of engagement with the latch housing for releasing the cover from the locking ring so as to permit removal of the hatch cover from the locking ring to provide access to the transfer tube. A davit assembly is provided which is connected with the transfer tube and the hatch cover to move the cover away and to provide guidance for closing-off the transfer tube. The locking ring and hatch cover also include cooperating keys and keyways for alignment when closing the transfer tube. The cover is provided with sealing rings and the latch housing and latches include cooperating cam surfaces to provide a tight locking engagement by compressing the sealing rings between the transfer tube and the hatch cover.« less
Altuntas, Nilgun; Turkyilmaz, Canan; Yildiz, Havva; Kulali, Ferit; Hirfanoglu, Ibrahim; Onal, Esra; Ergenekon, Ebru; Koç, Esin; Atalay, Yıldız
2014-05-01
We aimed to evaluate the validity and reliability of the Infant Breastfeeding Assessment Tool (IBFAT), the Mother Baby Assessment (MBA) Tool, and the LATCH scoring system. Mothers who delivered healthy, full-term infants in the Obstetrics & Gynecology Service of Gazi University, Ankara, Turkey, between December 2013 and January 2014 and their infants were included in the study. Forty-six randomly selected breastfeeding sessions were monitored and scored simultaneously by three researchers (Raters 1, 2, and 3) using LATCH, IBFAT, and the MBA Tool. Researchers put the score sheets in an envelope in order to hide them from each other. The compatibility of the scores given by three researchers was assessed by statistical methods. We found positive and significant correlation coefficients between 0.81 to 0.88 for the total MBA score, between 0.90 to 0.95 for the total IBFAT score, and between 0.85 to 0.91 for the total LATCH score. Correlation coefficients testing these three tools ranged from 0.71 to 0.88, with the minimum value being noted for the correlation between LATCH and IBFAT scores and the maximum value being noted for the correlation between LATCH and MBA scores. We found positive and significant correlations between researchers' scores for 46 observations using the three assessment tools. This study showed that these above-mentioned tools were compatible for the assessment of the efficiency of breastfeeding.
78 FR 60676 - Airworthiness Directives; The Boeing Company Airplanes
Federal Register 2010, 2011, 2012, 2013, 2014
2013-10-02
.... Option to rework/replace Between 3 and 24 work- $286 per latch... Between $541 and Between $65,461... compliance times specified, unless already done. (g) Replacement or Rework of Escape Slide Latch Assembly...
Cicchino, Jessica B; Jermakian, Jessica S
2015-06-01
The objective of this study was to determine if vehicle features associated with LATCH ease-of-use in laboratory studies with volunteers predict LATCH use and misuse in real-world child restraint installations. Vehicle characteristics were extracted from prior surveys of more than 100 top-selling 2010-13 vehicles. Use and correct use of LATCH was determined from records of more than 14,000 child restraint installations in these vehicles that were inspected by child passenger safety technicians at Safe Kids car seat checkup events during 2010-12. Logistic regression was used to examine the association between vehicle features and use and correct use of lower anchors and top tethers, controlling for other relevant installation features. Lower anchors were more likely to be used and correctly used when the clearance angle around them was greater than 54°, the force required to attach them to the lower anchors was less than 178N, and their depth within the seat bight was less than 4cm. Restraints were more likely to be attached correctly when installed with the lower anchors than with the seat belt. After controlling for lower anchor use and other installation features, the likelihood of tether use and correct use in installations of forward-facing restraints was significantly higher when there was no hardware present that could potentially be confused with the tether anchor or when the tether anchor was located on the rear deck, which is typical in sedans. There is converging evidence from laboratory studies with volunteers and real-world child restraint installations that vehicle features are associated with correct LATCH use. Vehicle designs that improve the ease of installing child restraints with LATCH could improve LATCH use rates and reduce child restraint misuse. Copyright © 2015 Elsevier Ltd and National Safety Council. All rights reserved.
Astronaut James Newman with latch hook for tether device
NASA Technical Reports Server (NTRS)
1993-01-01
Astronaut James H. Newman, mission specialist, shows off a latch hook for a tether device used during the STS-51 extravehicular activity (EVA) on September 16, 1993. Newman, on Discovery's middeck, appears surrounded by sleep restraints.
78 FR 9346 - Airworthiness Directives; The Boeing Company Airplanes
Federal Register 2010, 2011, 2012, 2013, 2014
2013-02-08
.... Option to rework/replace Between 3 and 24 $286 per latch.... Between $541 and Between $65,461 and latches... Comply with this AD within the compliance times specified, unless already done. (g) Replacement or Rework...
27. INTERIOR OF KITCHEN SHOWING ORIGINAL CABINETS, LATCHES AND PULLS, ...
27. INTERIOR OF KITCHEN SHOWING ORIGINAL CABINETS, LATCHES AND PULLS, AND WOOD-FRAME SLIDING-GLASS WINDOWS ABOVE SINK. VIEW TO EAST. - Rush Creek Hydroelectric System, Clubhouse Cottage, Rush Creek, June Lake, Mono County, CA
Cooled electronic system with thermal spreaders coupling electronics cards to cold rails
Chainer, Timothy J; Gaynes, Michael A; Graybill, David P; Iyengar, Madhusudan K; Kamath, Vinod; Kochuparambil, Bejoy J; Schmidt, Roger R; Schultz, Mark D; Simco, Daniel P; Steinke, Mark E
2013-07-23
Liquid-cooled electronic systems are provided which include an electronic assembly having an electronics card and a socket with a latch at one end. The latch facilitates securing of the card within the socket or removal of the card from the socket. A liquid-cooled cold rail is disposed at the one end of the socket, and a thermal spreader couples the electronics card to the cold rail. The thermal spreader includes first and second thermal transfer plates coupled to first and second surfaces on opposite sides of the card, and thermally conductive extensions extending from end edges of the plates, which couple the respective transfer plates to the liquid-cooled cold rail. The thermally conductive extensions are disposed to the sides of the latch, and the card is securable within or removable from the socket using the latch without removing the cold rail or the thermal spreader.
Method of fabricating a cooled electronic system
Chainer, Timothy J; Gaynes, Michael A; Graybill, David P; Iyengar, Madhusudan K; Kamath, Vinod; Kochuparambil, Bejoy J; Schmidt, Roger R; Schultz, Mark D; Simco, Daniel P; Steinke, Mark E
2014-02-11
A method of fabricating a liquid-cooled electronic system is provided which includes an electronic assembly having an electronics card and a socket with a latch at one end. The latch facilitates securing of the card within the socket. The method includes providing a liquid-cooled cold rail at the one end of the socket, and a thermal spreader to couple the electronics card to the cold rail. The thermal spreader includes first and second thermal transfer plates coupled to first and second surfaces on opposite sides of the card, and thermally conductive extensions extending from end edges of the plates, which couple the respective transfer plates to the liquid-cooled cold rail. The extensions are disposed to the sides of the latch, and the card is securable within or removable from the socket using the latch without removing the cold rail or the thermal spreader.
Design of High Speed and Low Offset Dynamic Latch Comparator in 0.18 µm CMOS Process
Rahman, Labonnah Farzana; Reaz, Mamun Bin Ibne; Yin, Chia Chieu; Ali, Mohammad Alauddin Mohammad; Marufuzzaman, Mohammad
2014-01-01
The cross-coupled circuit mechanism based dynamic latch comparator is presented in this research. The comparator is designed using differential input stages with regenerative S-R latch to achieve lower offset, lower power, higher speed and higher resolution. In order to decrease circuit complexity, a comparator should maintain power, speed, resolution and offset-voltage properly. Simulations show that this novel dynamic latch comparator designed in 0.18 µm CMOS technology achieves 3.44 mV resolution with 8 bit precision at a frequency of 50 MHz while dissipating 158.5 µW from 1.8 V supply and 88.05 µA average current. Moreover, the proposed design propagates as fast as 4.2 nS with energy efficiency of 0.7 fJ/conversion-step. Additionally, the core circuit layout only occupies 0.008 mm2. PMID:25299266
Skogen, Erik J.
2013-01-29
An optical set-reset (SR) latch is formed from a first electroabsorption modulator (EAM), a second EAM and a waveguide photodetector (PD) which are arranged in an optical and electrical feedback loop which controls the transmission of light through the first EAM to latch the first EAM in a light-transmissive state in response to a Set light input. A second waveguide PD controls the transmission of light through the second EAM and is used to switch the first EAM to a light-absorptive state in response to a Reset light input provided to the second waveguide PD. The optical SR latch, which may be formed on a III-V compound semiconductor substrate (e.g. an InP or a GaAs substrate) as a photonic integrated circuit (PIC), stores a bit of optical information and has an optical output for the logic state of that bit of information.
NASA Astrophysics Data System (ADS)
Shin, Sunhae; Rok Kim, Kyung
2016-04-01
We propose complement double-peak negative differential resistance (NDR) devices with ultrahigh peak-to-valley current ratio (PVCR) over 106 by combining tunnel diode with conventional CMOS and its compact five-state latch circuit by introducing standard ternary inverter (STI). At the “high”-state of STI, n-type NDR device (tunnel diode with nMOS) has 1st NDR characteristics with 1st peak and valley by band-to-band tunneling (BTBT) and trap-assisted tunneling (TAT), whereas p-type NDR device (tunnel diode with pMOS) has second NDR characteristics from the suppression of diode current by off-state MOSFET. The “intermediate”-state of STI permits double-peak NDR device to operate five-state latch with only four transistors, which has 33% area reduction compared with that of binary inverter and 57% bit-density reduction compared with binary latch.
Estimating Single-Event Logic Cross Sections in Advanced Technologies
NASA Astrophysics Data System (ADS)
Harrington, R. C.; Kauppila, J. S.; Warren, K. M.; Chen, Y. P.; Maharrey, J. A.; Haeffner, T. D.; Loveless, T. D.; Bhuva, B. L.; Bounasser, M.; Lilja, K.; Massengill, L. W.
2017-08-01
Reliable estimation of logic single-event upset (SEU) cross section is becoming increasingly important for predicting the overall soft error rate. As technology scales and single-event transient (SET) pulse widths shrink to widths on the order of the setup-and-hold time of flip-flops, the probability of latching an SET as an SEU must be reevaluated. In this paper, previous assumptions about the relationship of SET pulsewidth to the probability of latching an SET are reconsidered and a model for transient latching probability has been developed for advanced technologies. A method using the improved transient latching probability and SET data is used to predict logic SEU cross section. The presented model has been used to estimate combinational logic SEU cross sections in 32-nm partially depleted silicon-on-insulator (SOI) technology given experimental heavy-ion SET data. Experimental SEU data show good agreement with the model presented in this paper.
Motion synchronization of a mechanism to deploy and restow a truss beam
NASA Technical Reports Server (NTRS)
Lucy, M.
1988-01-01
The functions of the Control of Flexible Structures I (COFS I) deployer and retractor assembly (DRA) are primarily to deploy and retract the Mast I beam, and secondarily to latch, unlatch, and restow the DRA mechanism. The problems associated with the diagonal folding mechanism that retracts the beam is presented, the synchronization requirements critical to the process of restowing the beam is discussed, and a proposed solution to the problem of synchronization between the mechanical systems is presented. In addition, a detailed description is presented of the design and functioning of the DRA.
Radiation characterization report for the GPS Receiver microcontroller chip. Final report
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
1994-06-20
The overall objective of this characterization test was to determine the sensitivity of the Motorola 68332 32-bit microcontroller to radiation induced single event upset and latch-up (SEU/SEL). The microcontroller is a key component of the GPS Receiver which will be a subsystem of the satellite required for the {open_quotes}FORTE{close_quotes} experiment. Testing was conducted at the Single Event Effects Laboratory at Brookhaven National Laboratory. The results obtained included a latch-up (SEL) threshold LET (Linear Energy Transfer) of 20 MeV-CM{sub 2}/mg and an upset (SEU) threshold LET of 5 MeV-CM{sup 2}/mg. The SEU threshold is typical of this technology, commercial 0.8{mu}m HCMOS.more » Some flow errors were observed that were not reset by the internal watchdog timer of the 68332. It is important that the Receiver design include a monitor of the device, such as an external watch-dog timer, that would initiate a reset of the program when this type of upset occurs. The SEL threshold is lower than would be expected for this 12{mu}m epi layer process and suggests the need for a strategy that would allow for a hard reset of the controller when a latch-up event occurs. Analysis of the galactic cosmic ray spectrum for the FORTE orbit was done and the results indicate a worst case latch-up rate for this device of 6.3 {times} 10{sup {minus}5} latch-ups per device day or roughly one latch-up per 43.5 device years.« less
Structure-function analysis of the OB and latch domains of chlorella virus DNA ligase.
Samai, Poulami; Shuman, Stewart
2011-06-24
Chlorella virus DNA ligase (ChVLig) is a minimized eukaryal ATP-dependent DNA sealing enzyme with an intrinsic nick-sensing function. ChVLig consists of three structural domains, nucleotidyltransferase (NTase), OB-fold, and latch, that envelop the nicked DNA as a C-shaped protein clamp. The OB domain engages the DNA minor groove on the face of the duplex behind the nick, and it makes contacts to amino acids in the NTase domain surrounding the ligase active site. The latch module occupies the DNA major groove flanking the nick. Residues at the tip of the latch contact the NTase domain to close the ligase clamp. Here we performed a structure-guided mutational analysis of the OB and latch domains. Alanine scanning defined seven individual amino acids as essential in vivo (Lys-274, Arg-285, Phe-286, and Val-288 in the OB domain; Asn-214, Phe-215, and Tyr-217 in the latch), after which structure-activity relations were clarified by conservative substitutions. Biochemical tests of the composite nick sealing reaction and of each of the three chemical steps of the ligation pathway highlighted the importance of Arg-285 and Phe-286 in the catalysis of the DNA adenylylation and phosphodiester synthesis reactions. Phe-286 interacts with the nick 5'-phosphate nucleotide and the 3'-OH base pair and distorts the DNA helical conformation at the nick. Arg-285 is a key component of the OB-NTase interface, where it forms a salt bridge to the essential Asp-29 side chain, which is imputed to coordinate divalent metal catalysts during the nick sealing steps.
76 FR 53648 - Federal Motor Vehicle Safety Standards: Occupant Crash Protection
Federal Register 2010, 2011, 2012, 2013, 2014
2011-08-29
... when the continuous motion of spooling the belt out is stopped. From that point, the seat belt cannot... reaction to LATCH found that drivers who preferred installing a CRS with seat belt as opposed to LATCH...
Code of Federal Regulations, 2010 CFR
2010-10-01
... 49 Transportation 4 2010-10-01 2010-10-01 false Shoe, latch. 236.801 Section 236.801 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION..., MAINTENANCE, AND REPAIR OF SIGNAL AND TRAIN CONTROL SYSTEMS, DEVICES, AND APPLIANCES Definitions § 236.801...
Electronic door locking mechanism
Williams, Gary Lin; Kirby, Patrick Gerald
1997-01-01
The invention is a motorized linkage for engaging a thumb piece in a door mechanism. The device has an exterior lock assembly with a small battery cell and combination lock. Proper entry by a user of a security code allows the battery to operate a small motor within the exterior lock assembly. The small motor manipulates a cam-plunger which moves an actuator pin into a thumb piece. The user applies a force on to the thumb piece. This force is transmitted by the thumb piece to a latch engagement mechanism by the actuator pin. The latch engagement mechanism operates the door latch.
Nuclear reactor control apparatus
Sridhar, Bettadapur N.
1983-11-01
Nuclear reactor core safety rod release apparatus comprises a control rod having a detent notch in the form of an annular peripheral recess at its upper end, a control rod support tube for raising and lowering the control rod under normal conditions, latches pivotally mounted on the control support tube with free ends thereof normally disposed in the recess in the control rod, and cam means for pivoting the latches out of the recess in the control rod when a scram condition occurs. One embodiment of the invention comprises an additional magnetically-operated latch for releasing the control rod under two different conditions, one involving seismic shock.
Electronic door locking mechanism
Williams, G.L.; Kirby, P.G.
1997-10-21
The invention is a motorized linkage for engaging a thumb piece in a door mechanism. The device has an exterior lock assembly with a small battery cell and combination lock. Proper entry by a user of a security code allows the battery to operate a small motor within the exterior lock assembly. The small motor manipulates a cam-plunger which moves an actuator pin into a thumb piece. The user applies a force on to the thumb piece. This force is transmitted by the thumb piece to a latch engagement mechanism by the actuator pin. The latch engagement mechanism operates the door latch. 6 figs.
Preliminary Observations from the 2014 Sand Dunes Experiment
2014-10-01
sync (start) 06/01/2014 09:00 0.00 ms ( latched ) Clock sync (end) 06/18/2014 11:55:00 10.846 ms slow Drift rate 633.471 μs/day (slowing) 22...10m (faired Kevlar) 210.0 m Sample rate 9765.625 Hz Clock sync (start) 06/01/2014 (YD 152) 01:33 0.00s ( latched ) Clock sync (end) 06/19/2014 (YD...02/2014 07:43 0.00s ( latched ) Clock sync (end) 06/16/2014 01:10 38.527 ms fast Drift rate 2.8066 ms/day (fast) 32 Figure 30. SBE39
Fabrication and Assembly of High-Precision Hinge and Latch Joints for Deployable Optical Instruments
NASA Technical Reports Server (NTRS)
Phelps, James E.
1999-01-01
Descriptions are presented of high-precision hinge and latch joints that have been co-developed, for application to deployable optical instruments, by NASA Langley Research Center and Nyma/ADF. Page-sized versions of engineering drawings are included in two appendices to describe all mechanical components of both joints. Procedures for assembling the mechanical components of both joints are also presented. The information herein is intended to facilitate the fabrication and assembly of the high-precision hinge and latch joints, and enable the incorporation of these joints into the design of deployable optical instrument systems.
49 CFR 236.339 - Mechanical locking, maintenance requirements.
Code of Federal Regulations, 2010 CFR
2010-10-01
... 49 Transportation 4 2010-10-01 2010-10-01 false Mechanical locking, maintenance requirements. 236... Interlocking Rules and Instructions § 236.339 Mechanical locking, maintenance requirements. Locking and... prevented: (a) Mechanical machine—(1) Latch-operated locking. Raising lever latch block so that bottom...
Structure-Function Analysis of the OB and Latch Domains of Chlorella Virus DNA Ligase*
Samai, Poulami; Shuman, Stewart
2011-01-01
Chlorella virus DNA ligase (ChVLig) is a minimized eukaryal ATP-dependent DNA sealing enzyme with an intrinsic nick-sensing function. ChVLig consists of three structural domains, nucleotidyltransferase (NTase), OB-fold, and latch, that envelop the nicked DNA as a C-shaped protein clamp. The OB domain engages the DNA minor groove on the face of the duplex behind the nick, and it makes contacts to amino acids in the NTase domain surrounding the ligase active site. The latch module occupies the DNA major groove flanking the nick. Residues at the tip of the latch contact the NTase domain to close the ligase clamp. Here we performed a structure-guided mutational analysis of the OB and latch domains. Alanine scanning defined seven individual amino acids as essential in vivo (Lys-274, Arg-285, Phe-286, and Val-288 in the OB domain; Asn-214, Phe-215, and Tyr-217 in the latch), after which structure-activity relations were clarified by conservative substitutions. Biochemical tests of the composite nick sealing reaction and of each of the three chemical steps of the ligation pathway highlighted the importance of Arg-285 and Phe-286 in the catalysis of the DNA adenylylation and phosphodiester synthesis reactions. Phe-286 interacts with the nick 5′-phosphate nucleotide and the 3′-OH base pair and distorts the DNA helical conformation at the nick. Arg-285 is a key component of the OB-NTase interface, where it forms a salt bridge to the essential Asp-29 side chain, which is imputed to coordinate divalent metal catalysts during the nick sealing steps. PMID:21527793
Astronaut James Newman with latch hook for tether device
1993-09-19
STS051-26-002 (12-22 Sept 1993) --- Astronaut James H. Newman, mission specialist, shows off a latch hook for a tether device used during the STS-51 extravehicular activity (EVA) on September 16, 1993. Newman, on Discovery's middeck, appears surrounded by sleep restraints.
Internally damped, self-arresting vertical drop-weight apparatus
NASA Technical Reports Server (NTRS)
Ambur, Damodar R. (Inventor); Prasad, Chunchu B. (Inventor); Waters, William A. (Inventor); Stockum, Robert W. (Inventor); Walter, Manfred A. (Inventor)
1994-01-01
A vertical dropped-weight impact test machine has a dropped-weight barrel vertically supported on upper and lower support brackets. The dropped-weight barrel is chambered to receive a dropped-weight assembly having a latch pin at its upper end, a damping unit in the middle, and a tup at its lower end. The tup is adapted for gathering data during impact testing. The latch pin releasably engages a latch pin coupling assembly. The latch pin coupling assembly is attached to a winch via a halyard for raising and lowering the dropped-weight assembly. The lower end of the dropped-weight barrel is provided with a bounce-back arresting mechanism which is activated by the descending passage of the dropped-weight assembly. After striking the specimen, the dropped-weight assembly rebounds vertically and is caught by the bounce-back arresting mechanism. The damping unit of the dropped-weight assembly serves to dissipate energy from the rebounding dropped-weight assembly and prevents the dropped-weight assembly from rebounding from the self-arresting mechanism.
Internally damped, self-arresting vertical drop-weight impact test apparatus
NASA Technical Reports Server (NTRS)
Ambur, Damodar R. (Inventor); Prasad, Chunchu B. (Inventor); Waters, Jr., William A. (Inventor); Stockum, Robert W. (Inventor); Walter, Manfred A. (Inventor)
1996-01-01
A vertical dropped-weight impact test machine has a dropped-weight barrel vertically supported on upper and lower support brackets. The dropped-weight barrel is chambered to receive a dropped-weight assembly having a latch pin at its upper end, a damping unit in the middle, and a tup at its lower end. The tup is adapted for gathering data during impact testing. The latch pin releasably engages a latch pin coupling assembly. The latch pin coupling assembly is attached to a winch via a halyard for raising and lowering the dropped-weight assembly. The lower end of the dropped-weight barrel is provided with a bounce-back arresting mechanism which is activated by the descending passage of the dropped-weight assembly. After striking the specimen, the dropped-weight assembly rebounds vertically and is caught by the bounce-back arresting mechanism. The damping unit of the dropped-weight assembly serves to dissipate energy from the rebounding dropped-weight assembly and prevents the dropped-weight assembly from rebounding from the self-arresting mechanism.
Internally damped, self-arresting vertical drop-weight impact test apparatus
NASA Technical Reports Server (NTRS)
Ambur, Damodar R. (Inventor); Prasad, Chunchu B. (Inventor); Waters, Jr., William A. (Inventor); Stockum, Robert W. (Inventor); Water, Manfred A. (Inventor)
1995-01-01
A vertical dropped-weight impact test machine has a dropped-weight barrel vertically supported on upper and lower support brackets. The dropped-weight barrel is chambered to receive a dropped-weight assembly having a latch pin at its upper end, a damping unit in the middle, and a tup at its lower end. The tup is adapted for gathering data during impact testing. The latch pin releasably engages a latch pin coupling assembly. The latch pin coupling assembly is attached to a winch via a halyard for raising and lowering the dropped-weight assembly. The lower end of the dropped-weight barrel is provided with a bounce-back arresting mechanism which is activated by the descending passage of the dropped-weight assembly. After striking the specimen, the dropped-weight assembly rebounds vertically and is caught by the bounce-back arresting mechanism. The damping unit of the dropped-weight assembly serves to dissipate energy from the rebounding dropped-weight assembly and prevents the dropped-weight assembly from rebounding from the self-arresting mechanism.
Pulling tool for use with reeled tubing and method for operating tools from wellbores
DOE Office of Scientific and Technical Information (OSTI.GOV)
Pleasants, C.W.
1991-08-20
This patent describes a tool for latching to and/or pulling a well operating tool having a fishing neck from a downhole location in pipe in a well bore. It comprises an elongated tubular housing assembly defining a longitudinal bore; means connecting the housing assembly to an end of a string of reeled tubing for passing the housing assembly through the wellbore and into contact with the fishing neck and for introducing fluid into the longitudinal bore; means disposed on the housing assembly for automatically latching to the fishing neck upon the housing assembly engaging the fishing neck; means responsive tomore » a predetermined fluid condition in the bore for releasing the latching means from the fishing neck to permit the tool to be removed from the wellbore; and means responsive to a predetermined mechanical force exerted, via the reeled tubing, on the housing assembly and on the fishing neck for releasing the latching means from the fishing neck.« less
Data eye monitor method and apparatus
Gara, Alan G [Mount Kisco, NY; Marcella, James A [Rochester, MN; Ohmacht, Martin [Yorktown Heights, NY
2012-01-31
An apparatus and method for providing a data eye monitor. The data eye monitor apparatus utilizes an inverter/latch string circuit and a set of latches to save the data eye for providing an infinite persistent data eye. In operation, incoming read data signals are adjusted in the first stage individually and latched to provide the read data to the requesting unit. The data is also simultaneously fed into a balanced XOR tree to combine the transitions of all incoming read data signals into a single signal. This signal is passed along a delay chain and tapped at constant intervals. The tap points are fed into latches, capturing the transitions at a delay element interval resolution. Using XORs, differences between adjacent taps and therefore transitions are detected. The eye is defined by segments that show no transitions over a series of samples. The eye size and position can be used to readjust the delay of incoming signals and/or to control environment parameters like voltage, clock speed and temperature.
1945-08-18
were interconnected, how? ever,, it was found that one of the oscillators had an intermit - tent, defect-. This trouble was cleared by removing the...switches> i.e., two pairsL are included in.the unit," one of ä pair of selectors {the " fast selector") steps .each time the latch operates, the other (the...34slow seleotor") steps oiice eaoh time the fast seleotor completes 25 steps. Thus, a total of 625 steps, or changes in permutation, is involved be
NASA Astrophysics Data System (ADS)
Hansen, S. K.; Berkowitz, B.
2014-12-01
Recently, we developed an alternative CTRW formulation which uses a "latching" upscaling scheme to rigorously map continuous or fine-scale stochastic solute motion onto discrete transitions on an arbitrarily coarse lattice (with spacing potentially on the meter scale or more). This approach enables model simplification, among many other things. Under advection, for example, we see that many relevant anomalous transport problems may be mapped into 1D, with latching to a sequence of successive, uniformly spaced planes. On this formulation (which we term RP-CTRW), the spatial transition vector may generally be made deterministic, with CTRW waiting time distributions encapsulating all the stochastic behavior. We demonstrate the excellent performance of this technique alongside Pareto-distributed waiting times in explaining experiments across a variety of scales using only two degrees of freedom. An interesting new application of the RP-CTRW technique is the analysis of radial (push-pull) tracer tests. Given modern computational power, random walk simulations are a natural fit for the inverse problem of inferring subsurface parameters from push-pull test data, and we propose them as an alternative to the classical type curve approach. In particular, we explore the visibility of heterogeneity through non-Fickian behavior in push-pull tests, and illustrate the ability of a radial RP-CTRW technique to encapsulate this behavior using a sparse parameterization which has predictive value.
78 FR 18922 - Airworthiness Directives; The Boeing Company Airplanes
Federal Register 2010, 2011, 2012, 2013, 2014
2013-03-28
... specifically invite comments on the overall regulatory, economic, environmental, and energy aspects of this..., or incorrect rigging. (iii) Repeat the high frequency eddy current (HFEC) or magnetic particle... inspection of the cam latches and latch pins for discrepancies; and an HFEC or magnetic particle inspection...
[Discuss about Alarm Requirements of Standards for Tests of Patient Monitor].
Feng, Ting
This paper introduces the alarm requirements of standards of patient monitor and expounds their significance for tests and guidance for patient monitor, then discusses whether technical alarm should not be closed and it latching alarm and non-latching alarm can not exist together.
A modular docking mechanism for in-orbit assembly and spacecraft servicing
NASA Technical Reports Server (NTRS)
Gampe, F.; Priesett, K.; Bentall, R. H.
1985-01-01
A Docking Mechanism concept is described which is suitable for use with autonomous docking systems. The central feature of using simple cylindrical handles on one side and a type of prism seating on the other is offered as a practical method of achieving a standardized structural interface without freezing continued development of the latches, either technically or commercially. The main emphasis in docking mechanism concepts is in two directions: (1) a very simple docking mechanism, involving mainly the latch mechanism to achieve a structural link; and (2) a sophisticated Docking Mechanism, where the latch mechanism is designed for nonrigid spacecraft and the achievement of very low dynamic interactions between spacecraft during the docking process.
Magnetic latch trigger for inherent shutdown assembly
Sowa, Edmund S.
1976-01-01
An inherent shutdown assembly for a nuclear reactor is provided. A neutron absorber is held ready to be inserted into the reactor core by a magnetic latch. The latch includes a magnet whose lines of force are linked by a yoke of material whose Curie point is at the critical temperature of the reactor at which the neutron absorber is to be inserted into the reactor core. The yoke is in contact with the core coolant or fissionable material so that when the coolant or the fissionable material increase in temperature above the Curie point the yoke loses its magnetic susceptibility and the magnetic link is broken, thereby causing the absorber to be released into the reactor core.
Novel latch for adiabatic quantum-flux-parametron logic
DOE Office of Scientific and Technical Information (OSTI.GOV)
Takeuchi, Naoki, E-mail: takeuchi-naoki-kx@ynu.jp; Yamanashi, Yuki; Yoshikawa, Nobuyuki
2014-03-14
We herein propose the quantum-flux-latch (QFL) as a novel latch for adiabatic quantum-flux-parametron (AQFP) logic. A QFL is very compact and compatible with AQFP logic gates and can be read out in one clock cycle. Simulation results revealed that the QFL operates at 5 GHz with wide parameter margins of more than ±22%. The calculated energy dissipation was only ∼0.1 aJ/bit, which yields a small energy delay product of 20 aJ·ps. We also designed shift registers using QFLs to demonstrate more complex circuits with QFLs. Finally, we experimentally demonstrated correct operations of the QFL and a 1-bit shift register (a D flip-flop)
Making A D-Latch Sensitive To Alpha Particles
NASA Technical Reports Server (NTRS)
Buehler, Martin G.; Blaes, Brent R.; Nixon, Robert H.
1994-01-01
Standard complementary metal oxide/semiconductor (CMOS) D-latch integrated circuit modified to increase susceptibility to single-event upsets (SEU's) (changes in logic state) caused by impacts of energetic alpha particles. Suitable for use in relatively inexpensive bench-scale SEU tests of itself and of related integrated circuits like static random-access memories.
Push-To-Lock, Push-To-Release Mechanism
NASA Technical Reports Server (NTRS)
Lozano, Anselmo, Jr.
1991-01-01
Latch locked or unlocked with single motion of hand. No tools needed to operate it, and user easily opens or closes it with heavily gloved hand. When unlocked, stem free of main body. In locked state, dowel pins in main body hold stem. Latch equipped with lock and key so only authorized users operate it.
Remote controlled vacuum joint closure mechanism
Doll, David W.; Hager, E. Randolph
1986-01-01
A remotely operable and maintainable vacuum joint closure mechanism for a noncircular aperture is disclosed. The closure mechanism includes an extendible bellows coupled at one end to a noncircular duct and at its other end to a flange assembly having sealed grooves for establishing a high vacuum seal with the abutting surface of a facing flange which includes an aperture forming part of the system to be evacuated. A plurality of generally linear arrangements of pivotally coupled linkages and piston combinations are mounted around the outer surface of the duct and aligned along the length thereof. Each of the piston/linkage assemblies is adapted to engage the flange assembly by means of a respective piston and is further coupled to a remote controlled piston drive shaft to permit each of the linkages positioned on a respective flat outer surface of the duct to simultaneously and uniformly displace a corresponding piston and the flange assembly with which it is in contact along the length of the duct in extending the bellows to provide a high vacuum seal between the movable flange and the facing flange. A plurality of latch mechanisms are also pivotally mounted on the outside of the duct. A first end of each of the latch mechanisms is coupled to a remotely controlled latch control shaft for displacing the latch mechanism about its pivot point. In response to the pivoting displacement of the latch mechanism, a second end thereof is displaced so as to securely engage the facing flange.
Johnson, Robert P; Fleming, Aaron M; Jin, Qian; Burrows, Cynthia J; White, Henry S
2014-08-19
The latch region of the wild-type protein pore α-hemolysin (α-HL) constitutes a sensing zone for individual abasic sites (and furan analogs) in double-stranded DNA (dsDNA). The presence of an abasic site or furan within a DNA duplex, electrophoretically captured in the α-HL vestibule and positioned at the latch region, can be detected based on the current blockage prior to duplex unzipping. We investigated variations in blockage current as a function of temperature (12-35°C) and KCl concentration (0.15-1.0 M) to understand the origin of the current signature and to optimize conditions for identifying the base modification. In 1 M KCl solution, substitution of a furan for a cytosine base in the latch region results in an ∼ 8 kJ mol(-1) decrease in the activation energy for ion transport through the protein pore. This corresponds to a readily measured ∼ 2 pA increase in current at room temperature. Optimal resolution for detecting the presence of a furan in the latch region is achieved at lower KCl concentrations, where the noise in the measured blockage current is significantly lower. The noise associated with the blockage current also depends on the stability of the duplex (as measured from the melting temperature), where a greater noise in the measured blockage current is observed for less stable duplexes. Copyright © 2014 Biophysical Society. Published by Elsevier Inc. All rights reserved.
Sievers, Robert K.; Cooper, Martin H.; Tupper, Robert B.
1987-01-01
A self-actuated shutdown system incorporated into a reactivity control assembly in a nuclear reactor includes pumping means for creating an auxiliary downward flow of a portion of the heated coolant exiting from the fuel assemblies disposed adjacent to the control assembly. The shutdown system includes a hollow tubular member which extends through the outlet of the control assembly top nozzle so as to define an outer annular flow channel through the top nozzle outlet separate from an inner flow channel for primary coolant flow through the control assembly. Also, a latching mechanism is disposed in an inner duct of the control assembly and is operable for holding absorber bundles in a raised position in the control assembly and for releasing them to drop them into the core of the reactor for shutdown purposes. The latching mechanism has an inner flow passage extending between and in flow communication with the absorber bundles and the inner flow channel of the top nozzle for accommodating primary coolant flow upwardly through the control assembly. Also, an outer flow passage separate from the inner flow passage extends through the latching mechanism between and in flow communication with the inner duct and the outer flow channel of the top nozzle for accommodating inflow of a portion of the heated coolant from the adjacent fuel assemblies. The latching mechanism contains a magnetic material sensitive to temperature and operable to cause mating or latching together of the components of the latching mechanism when the temperature sensed is below a known temperature and unmating or unlatching thereof when the temperature sensed is above a given temperature. The temperature sensitive magnetic material is positioned in communication with the heated coolant flow through the outer flow passage for directly sensing the temperature thereof. Finally, the pumping means includes a jet induction pump nozzle and diffuser disposed adjacent the bottom nozzle of the control assembly and in flow communication with the inlet thereof. The pump nozzle is operable to create an upward driving flow of primary coolant through the pump diffuser and then to the absorber bundles. The upward driving flow of primary coolant, in turn, creates a suction head within the outer flow channel of the top nozzle and thereby an auxiliary downward flow of the heated coolant portion exiting from the upper end of the adjacent fuel assemblies through the outer flow channel to the pump nozzle via the outer flow passage of the latching mechanism and an annular space between the outer and inner spaced ducts of the control assembly housing. The temperature of the heated coolant exiting from the adjacent fuel assemblies can thereby be sensed directly by the temperature sensitive magnetic material in the latching mechanism.
Segmented-memory recurrent neural networks.
Chen, Jinmiao; Chaudhari, Narendra S
2009-08-01
Conventional recurrent neural networks (RNNs) have difficulties in learning long-term dependencies. To tackle this problem, we propose an architecture called segmented-memory recurrent neural network (SMRNN). A symbolic sequence is broken into segments and then presented as inputs to the SMRNN one symbol per cycle. The SMRNN uses separate internal states to store symbol-level context, as well as segment-level context. The symbol-level context is updated for each symbol presented for input. The segment-level context is updated after each segment. The SMRNN is trained using an extended real-time recurrent learning algorithm. We test the performance of SMRNN on the information latching problem, the "two-sequence problem" and the problem of protein secondary structure (PSS) prediction. Our implementation results indicate that SMRNN performs better on long-term dependency problems than conventional RNNs. Besides, we also theoretically analyze how the segmented memory of SMRNN helps learning long-term temporal dependencies and study the impact of the segment length.
Federal Register 2010, 2011, 2012, 2013, 2014
2011-03-29
... locked open during taxi, takeoff and landing. The adjacent forward wall/bulkhead interior structure will... inches of energy absorbing protective padding (foam or equivalent), such as Ensolite. 3. Thoracic Trauma... occupied, the lavatory door must be latched open for takeoff and landing and must remain latched under the...
Electrical latching of microelectromechanical devices
Garcia, Ernest J.; Sleefe, Gerard E.
2004-11-02
Methods are disclosed for row and column addressing of an array of microelectromechanical (MEM) devices. The methods of the present invention are applicable to MEM micromirrors or memory elements and allow the MEM array to be programmed and maintained latched in a programmed state with a voltage that is generally lower than the voltage required for electrostatically switching the MEM devices.
Hatch latch mechanism for Spacelab scientific airlock
NASA Technical Reports Server (NTRS)
Terhaar, G. R.
1979-01-01
The requirements, design tradeoff, design, and performance of the Spacelab scientific airlock hatch latching mechanisms are described. At space side the hatch is closed and held against internal airlock/module pressure by 12 tangential overcenter hooks driven by a driver. At module side the hatch is held by 4 hooks driven by rollers running on a cammed driver.
Planar electroluminescent panel techniques
NASA Technical Reports Server (NTRS)
Kerr, C.; Kell, R. E.
1973-01-01
Investigations of planar electroluminescent multipurpose displays with latch-in memory are described. An 18 x 24 in. flat, thin address panel with elements spacing of 0.100 in. was constructed which demonstrated essentially uniform luminosity of 3-5 foot lamberts for each of its 43200 EL cells. A working model of a 4-bit EL-PC (electroluminescent photoconductive) electrooptical decoder was made which demonstrated the feasibility of this concept. A single-diagram electroluminescent display device with photoconductive-electroluminescent latch-in memory was constructed which demonstrated the conceptual soundness of this principle. Attempts to combine these principles in a single PEL multipurpose display with latch-in memory were unsuccessful and were judged to exceed the state-of-the-art for close-packed (0.10 in. centers) photoconductor-electroluminescent cell assembly.
SKITTER/implement mechanical interface
NASA Technical Reports Server (NTRS)
Cash, John Wilson, III; Cone, Alan E.; Garolera, Frank J.; German, David; Lindabury, David Peter; Luckado, Marshall Cleveland; Murphey, Craig; Rowell, John Bryan; Wilkinson, Brad
1988-01-01
SKITTER (Spacial Kinematic Inertial Translatory Tripod Extremity Robot) is a three-legged transport vehicle designed to perform under the unique environment of the moon. The objective of this project was to design a mechanical interface for SKITTER. This mechanical latching interface will allow SKITTER to use a series of implements such as drills, cranes, etc., and perform different tasks on the moon. The design emphasized versatility and detachability; that is, the interface design is the same for all implements, and connection and detachment is simple. After consideration of many alternatives, a system of three identical latches at each of the three interface points was chosen. The latching mechanism satisfies the design constraints because it facilitates connection and detachment. Also, the moving parts are protected from the dusty environment by housing plates.
NASA Technical Reports Server (NTRS)
Lynch, R. A.
1972-01-01
The design approach and development demonstration are presented for a flightweight, miniature, magnetic latching shutoff valve, suitable for use with the ruggedized H2 and NH3 resistojet and the biowaste resistojet. The design criteria established provided for compatibility with specified ruggedized resistojet propellants as well as the biowaste and other propulsion system propellants.
Karl J. Romanowicz; Evan S. Kane; Lynette R. Potvin; Aleta L. Daniels; Randy Kolka; Erik A. Lilleskov
2015-01-01
Aims. Our objective was to assess the impacts of water table position and plant functional groups on peatland extracellular enzyme activity (EEA) framed within the context of the enzymic latch hypothesis. Methods. We utilized a full factorial experiment with 2 water table (WT) treatments (high and low) and 3 plant functional...
Photocopy of drawing. ALTITUDE CHAMBERS L & R STRUCTURES. NASA, ...
Photocopy of drawing. ALTITUDE CHAMBERS L & R STRUCTURES. NASA, John F. Kennedy Space Center, Florida. Drawing 68-K-L-11213, NASA KSC, March, 1971. DOOR LATCH MECHANISM & DOOR LATCHING RATCHET. Sheet 14 - Cape Canaveral Air Force Station, Launch Complex 39, Altitude Chambers, First Street, between Avenue D and Avenue E, Cape Canaveral, Brevard County, FL
Code of Federal Regulations, 2013 CFR
2013-10-01
... visibility, 14 air bags, 15 seat belts, 16 structure, 17 latch, 18 vehicle speed control, 19 tires, 20 wheels... exterior lighting, 13 visibility, 14 air bags, 15 seat belts, 16 structure, 17 latch, 18 vehicle speed... of service brake system (i.e., hydraulic or air), the information required by this subsection shall...
NASA Technical Reports Server (NTRS)
King, Guy L.; Schneider, William C.
1989-01-01
A pyrotechnic actuated structural release device is disclosed which is mechanically two fault tolerant for release. The device comprises a fastener plate and fastener body each attachable to one of a pair of structures to be joined. The fastener plate and the fastener body are fastened by a dual swivel toggle member. The toggle member is supported at one end on the fastener plate and mounted for universal pivotal movement thereon. Its other end is received in a central opening in the fastener body, and has a universally mounted retainer ring member. The toggle member is restrained by three retractable latching pins symmetrically disposed in equiangular spacing about the axis of the toggle member and positionable in latching engagement with the retainer ring member on the toggle member. Each pin is retractable by a pyrotechnic charge, the expanding gases of which are applied to a pressure receiving face on the latch pins to effect retraction from the ring member. While retraction of all three pins releases the ring member, the fastener is mechanically two fault tolerant since the failure of any single one or pair of the latch pins to retract results in an asymmetrical loading on the ring member and its dual pivotal movement ensures a release.
A gate-latch-lock mechanism for hormone signalling by abscisic acid receptors
DOE Office of Scientific and Technical Information (OSTI.GOV)
Melcher, Karsten; Ng, Ley-Moy; Zhou, X Edward
2010-01-12
Abscisic acid (ABA) is a ubiquitous hormone that regulates plant growth, development and responses to environmental stresses. Its action is mediated by the PYR/PYL/RCAR family of START proteins, but it remains unclear how these receptors bind ABA and, in turn, how hormone binding leads to inhibition of the downstream type 2C protein phosphatase (PP2C) effectors. Here we report crystal structures of apo and ABA-bound receptors as well as a ternary PYL2-ABA-PP2C complex. The apo receptors contain an open ligand-binding pocket flanked by a gate that closes in response to ABA by way of conformational changes in two highly conserved β-loopsmore » that serve as a gate and latch. Moreover, ABA-induced closure of the gate creates a surface that enables the receptor to dock into and competitively inhibit the PP2C active site. A conserved tryptophan in the PP2C inserts directly between the gate and latch, which functions to further lock the receptor in a closed conformation. Together, our results identify a conserved gate-latch-lock mechanism underlying ABA signalling.« less
Method and apparatus for preloading a joint by remotely operable means
NASA Technical Reports Server (NTRS)
Kahn, Jon B. (Inventor)
1993-01-01
The invention is a method and apparatus for joining structures, an active structure and a passive structure, and imposing a tensile pre-load on the joint by a remotely operable mechanism comprising a heat contractible joining element. The method and apparatus include mounting on the structure, a probe shaft of material which is transformable from an expanded length to a contracted length when heated to a specific temperature range. The shaft is provided with a probe head which is receivable in a receptacle opening formed in the passive structure, when the active structure is moved into engagement therewith by an appropriate manipulator mechanism. A latching system mounted on the structure adjacent to the receptacle opening captures the probe head, when the probe head is inserted a predetermined amount. A heating coil on the shaft is energizable by remote control for heating the shaft to a temperature range which transforms the shaft to its contracted length, whereby a latching shoulder thereof engages latching elements of the latching system and imposes a tensile preload on the structural joint. Provision is also made for manually adjusting the probe head on the shaft to allow for manual detachment of the structures or manual preloading of the structural joint.
Method and apparatus for preloading a joint by remotely operable means
NASA Technical Reports Server (NTRS)
Shelton, Robert O. (Inventor)
1992-01-01
The invention is a method and apparatus for joining structures, an active structure and a passive structure, and imposing a tensile pre-load on the joint by a remotely operable mechanism comprising a heat contractible joining element. The method and apparatus include mounting on the structure, a probe shaft of material which is transformable from an expanded length to a contracted length when heated to a specific temperature range. The shaft is provided with a probe head which is receivable in a receptacle opening formed in the passive structure, when the active structure is moved into engagement therewith by an appropriate manipulator mechanism. A latching system mounted on the structure adjacent to the receptacle opening captures the probe head, when the probe head is inserted a predetermined amount. A heating coil on the shaft is energizable by remote control for heating the shaft to a temperature range which transforms the shaft to its contracted length, whereby a latching shoulder thereof engages latching elements of the latching system and imposes a tensile preload on the structural joint. Provision is also made for manually adjusting the probe head on the shaft to allow for manual detachment of the structures or manual preloading of the structural joint.
FPGA Implementation of Metastability-Based True Random Number Generator
NASA Astrophysics Data System (ADS)
Hata, Hisashi; Ichikawa, Shuichi
True random number generators (TRNGs) are important as a basis for computer security. Though there are some TRNGs composed of analog circuit, the use of digital circuits is desired for the application of TRNGs to logic LSIs. Some of the digital TRNGs utilize jitter in free-running ring oscillators as a source of entropy, which consume large power. Another type of TRNG exploits the metastability of a latch to generate entropy. Although this kind of TRNG has been mostly implemented with full-custom LSI technology, this study presents an implementation based on common FPGA technology. Our TRNG is comprised of logic gates only, and can be integrated in any kind of logic LSI. The RS latch in our TRNG is implemented as a hard-macro to guarantee the quality of randomness by minimizing the signal skew and load imbalance of internal nodes. To improve the quality and throughput, the output of 64-256 latches are XOR'ed. The derived design was verified on a Xilinx Virtex-4 FPGA (XC4VFX20), and passed NIST statistical test suite without post-processing. Our TRNG with 256 latches occupies 580 slices, while achieving 12.5Mbps throughput.
Retractable tool bit having latch type catch mechanism
NASA Technical Reports Server (NTRS)
Voellmer, George (Inventor)
1993-01-01
A retractable tool bit assembly for a tool such as an allen key is presented. The assembly includes one or more spring loaded nestable or telescoping tubular sections together with a catch mechanism for capturing and holding the tool in its retracted position. The catch mechanism consists of a latch mechanism located in a base section and which engages a conically shaped tool head located at the inner end of the tool. The tool head adjoins an eccentric oval type neck portion which extends to a rear lip of the tool head. The latch mechanism releases when the ovular neck portion rotates about the catch members upon actuation of a rotary tool drive motor. When released, all the telescoping sections and the tool extends fully outward to a use position.
Electronic scanning pressure measuring system and transducer package
NASA Technical Reports Server (NTRS)
Coe, C. F. (Inventor); Parra, G. T.
1984-01-01
An electronic scanning pressure system that includes a plurality of pressure transducers is examined. A means obtains an electrical signal indicative of a pressure measurement from each of the plurality of pressure transducers. A multiplexing means is connected for selectivity supplying inputs from the plurality of pressure transducers to the signal obtaining means. A data bus connects the plurality of pressure transducers to the multiplexing means. A latch circuit is connected to supply control inputs to the multiplexing means. An address bus is connected to supply an address signal of a selected one of the plurality of pressure transducers to the latch circuit. In operation, each of the pressure transducers is successively scanned by the multiplexing means in response to address signals supplied on the address bus to the latch circuit.
Latching Solenoid-Operated Ball Valve
NASA Technical Reports Server (NTRS)
Brudnicki, Myron
1994-01-01
Proposed solenoid-operated ball valve latches in open or closed position until energized to change position. Electrical energy consumed only during opening or closing motion. Valve ball contains central channel through which fluid could flow. Made of highly magnetically permeable steel. When appropriate coil(s) energized by brief pulse (or pulses) of electrical current at appropriate polarity, ball rotates clockwise until permanent magnets come to rest against hard stops in housing, and inlet and outlet ports aligned with central channel so fluid flows through valve. Magnets adhere to stops by magnetic attraction, latching valve in open position. To close valve, appropriate coil(s) energized by pulse (or pulses) of appropriate polarity to generate magnetic forces rotating ball counterclockwise until magnets make contact with hard stops, and inlet and outlet ports sealed.
Microelectromechanical safe arm device
Roesler, Alexander W [Tijeras, NM
2012-06-05
Microelectromechanical (MEM) apparatus and methods for operating, for preventing unintentional detonation of energetic components comprising pyrotechnic and explosive materials, such as air bag deployment systems, munitions and pyrotechnics. The MEM apparatus comprises an interrupting member that can be moved to block (interrupt) or complete (uninterrupt) an explosive train that is part of an energetic component. One or more latching members are provided that engage and prevent the movement of the interrupting member, until the one or more latching members are disengaged from the interrupting member. The MEM apparatus can be utilized as a safe and arm device (SAD) and electronic safe and arm device (ESAD) in preventing unintentional detonations. Methods for operating the MEM apparatus include independently applying drive signals to the actuators coupled to the latching members, and an actuator coupled to the interrupting member.
High Gain and Wide Range Time Amplifier Using Inverter Delay Chain in SR Latches
NASA Astrophysics Data System (ADS)
Lee, Jaejun; Lee, Sungho; Song, Yonghoon; Nam, Sangwook
This paper presents a time amplifier design that improves time resolution using an inverter chain delay in SR latches. Compared with the conventional design, the proposed time amplifier has better characteristics such as higher gain, wide range, and small die size. It is implemented using 0.13µm standard CMOS technology and the experimental results agree well with the theory.
Dual-latching solenoid-actuated valve assembly
NASA Technical Reports Server (NTRS)
Brudnicki, Myron J. (Inventor); Yang, Jeff (Inventor)
1994-01-01
A tube-type shutoff valve is electrically positioned to its open or closed position by a concentric electromagnetic solenoid. The valve is dual latching in that the armature of the solenoid maintains the sliding tube of the valve in an open or closed position by means of permanent magnets which are effective when current is not supplied to the solenoid. The valve may also be actuated manually.
Non-latching relay switch assembly
Duimstra, Frederick A.
1991-01-01
A non-latching relay switch assembly which includes a coil section and a switch or contact section. The coil section includes a permanent magnet and an electromagnet. The respective sections are arranged in separate locations or cavities in the assembly. The switch has a "normal" position and is selectively switched by an overriding electromagnetic assembly. The switch returns to the "normal" position when the overriding electromagnetic assembly is inactive.
Reliability of Lactation Assessment Tools Applied to Overweight and Obese Women.
Chapman, Donna J; Doughty, Katherine; Mullin, Elizabeth M; Pérez-Escamilla, Rafael
2016-05-01
The interrater reliability of lactation assessment tools has not been evaluated in overweight/obese women. This study aimed to compare the interrater reliability of 4 lactation assessment tools in this population. A convenience sample of 45 women (body mass index > 27.0) was videotaped while breastfeeding (twice daily on days 2, 4, and 7 postpartum). Three International Board Certified Lactation Consultants independently rated each videotaped session using 4 tools (Infant Breastfeeding Assessment Tool [IBFAT], modified LATCH [mLATCH], modified Via Christi [mVC], and Riordan's Tool [RT]). For each day and tool, we evaluated interrater reliability with 1-way repeated-measures analyses of variance, intraclass correlation coefficients (ICCs), and percentage absolute agreement between raters. Analyses of variance showed significant differences between raters' scores on day 2 (all scales) and day 7 (RT). Intraclass correlation coefficient values reflected good (mLATCH) to excellent reliability (IBFAT, mVC, and RT) on days 2 and 7. All day 4 ICCs reflected good reliability. The ICC for mLATCH was significantly lower than all others on day 2 and was significantly lower than IBFAT (day 7). Percentage absolute interrater agreement for scale components ranged from 31% (day 2: observable swallowing, RT) to 92% (day 7: IBFAT, fixing; and mVC, latch time). Swallowing scores on all scales had the lowest levels of interrater agreement (31%-64%). We demonstrated differences in the interrater reliability of 4 lactation assessment tools when applied to overweight/obese women, with the lowest values observed on day 4. Swallowing assessment was particularly unreliable. Researchers and clinicians using these scales should be aware of the differences in their psychometric behavior. © The Author(s) 2015.
Remote controlled vacuum joint closure mechanism
Doll, D.W.; Hager, E.R.
1984-02-22
A remotely operable and maintainable vacuum joint closure mechanism for a noncircular aperture is disclosed. The closure mechanism includes an extendible bellows coupled at one end to a noncircular duct and at its other end to a flange assembly having sealed grooves for establishing a high vacuum seal with the abutting surface of a facing flange which includes an aperture forming part of the system to be evacuated. A plurality of generally linear arrangements of pivotally coupled linkages and piston combinations are mounted around the outer surface of the duct and aligned along the length thereof. Each of the piston/linkage assemblies is adapted to engage the flange assembly by means of a respective piston and is further coupled to a remote controlled piston drive shaft to permit each of the linkages positioned on a respective flat outer surface of the duct to simultaneously and uniformly displace a corresponding piston and the flange assembly with which it is in contact along the length of the duct in extending the bellows to provide a high vacuum seal between the movable flange and the facing flange. A plurality of latch mechanisms are also pivotally mounted on the outside of the duct. A first end of each of the latch mechanisms is coupled to a remotely controlled latch control shaft for displacing the latch mechanism about its pivot point. In response to the pivoting displacement of the latch mechanism, a second end thereof is displaced so as to securely engage the facing flange and maintain the high vacuum seal established by the displacement of the flange assembly and extension of the bellows without displacing the entire duct.
Marts, Donna J.; Richardson, John G.; Albano, Richard K.; Morrison, Jr., John L.
1995-01-01
This invention discloses a D.C. magnetic latching solenoid that retains a moving armature in a first or second position by means of a pair of magnets, thereby having a zero-power requirement after actuation. The first or second position is selected by reversing the polarity of the D.C. voltage which is enough to overcome the holding power of either magnet and transfer the armature to an opposite position. The coil is then de-energized.
Manned maneuvering unit latching mechanism
NASA Technical Reports Server (NTRS)
Allton, C. S.
1980-01-01
The astronaut/Manned Maneuvering Unit interface, which presented a challenging set of requirements for a latching mechanism, is described. A spring loaded cam segment with variable ratio pulley release actuator was developed to meet the requirements. To preclude jamming of the mechanism, special precautions were taken such as spring loaded bearing points and careful selection of materials to resist cold welding. The mechanism successfully passed a number of tests which partially simulated orbital conditions.
Bistable (latching) solenoid actuated propellant isolation valve
NASA Technical Reports Server (NTRS)
Wichmann, H.; Deboi, H. H.
1979-01-01
The design, fabrication, assembly and test of a development configuration bistable (latching) solenoid actuated propellant isolation valve suitable for the control hydrazine and liquid fluorine to an 800 pound thrust rocket engine is described. The valve features a balanced poppet, utilizing metal bellows, a hard poppet/seat interface and a flexure support system for the internal moving components. This support system eliminates sliding surfaces, thereby rendering the valve free of self generated particles.
Method and apparatus for releasably connecting first and second objects
NASA Technical Reports Server (NTRS)
Monford, Leo G., Jr. (Inventor)
1991-01-01
The apparatus and method are disclosed for releasably connecting first and second objects, where a magnetic end effector may include at least one elongated pin number, a proximal end of which is connected to the first object and the distal end of which may be inserted into a receiving portion in the second object. Latch members are carried by the pin member for radial movement between retracted and expanded positions for releasing and locking, respectively, first and second objects. A plunger member carried by the pin member is axially moveable between first and second positions. In the first plunger position, the latch members are located in the expanded (locked) position and in the second plunger position the latch members are released for movement to retracted or unlocked position. The magnetic end effector is provided for releasable attachment to the first object and for moving the plunger member to the second position, releasing the first object.
Fast frequency divider circuit using combinational logic
DOE Office of Scientific and Technical Information (OSTI.GOV)
Helinski, Ryan
The various technologies presented herein relate to performing on-chip frequency division of an operating frequency of a ring oscillator (RO). Per the various embodiments herein, a conflict between RO size versus operational frequency can be addressed by dividing the output frequency of the RO to a frequency that can be measured on-chip. A frequency divider circuit (comprising NOR gates and latches, for example) can be utilized in conjunction with the RO on the chip. In an embodiment, the frequency divider circuit can include a pair of latches coupled to the RO to facilitate dividing the oscillating frequency of the ROmore » by 2. In another embodiment, the frequency divider circuit can include four latches (operating in pairs) coupled to the RO to facilitate dividing the oscillating frequency of the RO by 4. A plurality of ROs can be MUXed to the plurality of ROs by a single oscillation-counting circuit.« less
Debris protection cover assembly for cable connectors
NASA Technical Reports Server (NTRS)
Yovan, Roger D. (Inventor)
1999-01-01
A protective cover assembly for an end of a cable connector having a cable housing that encloses a plurality of connective pins or sockets and that satisfies all requirements for space applications. A connector body flange is formed at the extremity of a cable and is positioned so that it may register with a corresponding connector body flange on the end of a companion cable to which a connection is to be made, one cable end having cable lead pins and the companion cable end having lead sockets with which the pins register. A latch mechanism having a latch housing is received in the connector body flange and a crank connected to a manually rotatable cap actuates a spring-loaded latch element that is engageable with a connector body flange to secure or to release the cover assembly with the simple twisting motion of the cap, thereby simplifying the task of effecting coupling and decoupling of the cable ends.
Secure RFID tag or sensor with self-destruction mechanism upon tampering
DOE Office of Scientific and Technical Information (OSTI.GOV)
Nekoogar, Faranak; Dowla, Farid; Twogood, Richard
A circuit board anti-tamper mechanism comprises a circuit board having a frangible portion, a trigger having a trigger spring, a trigger arming mechanism actuated by the trigger wherein the trigger arming mechanism is initially non-actuated, a force producing mechanism, a latch providing mechanical communication between the trigger arming mechanism and the force producing mechanism, wherein the latch initially retains the force producing mechanism in a refracted position. Arming pressure applied to the trigger sufficient to overcome the trigger spring force will actuate the trigger arming mechanism, causing the anti-tamper mechanism to be armed. Subsequent tampering with the anti-tamper mechanism resultsmore » in a decrease of pressure on the trigger below the trigger spring force, thereby causing the trigger arming mechanism to actuate the latch, thereby releasing the force producing mechanism to apply force to the frangible portion of the circuit board, thereby breaking the circuit board.« less
Kim, Kyung Lock; Sung, Gihyun; Sim, Jaehwan; Murray, James; Li, Meng; Lee, Ara; Shrinidhi, Annadka; Park, Kyeng Min; Kim, Kimoon
2018-04-27
Here we report ultrastable synthetic binding pairs between cucurbit[7]uril (CB[7]) and adamantyl- (AdA) or ferrocenyl-ammonium (FcA) as a supramolecular latching system for protein imaging, overcoming the limitations of protein-based binding pairs. Cyanine 3-conjugated CB[7] (Cy3-CB[7]) can visualize AdA- or FcA-labeled proteins to provide clear fluorescence images for accurate and precise analysis of proteins. Furthermore, controllability of the system is demonstrated by treating with a stronger competitor guest. At low temperature, this allows us to selectively detach Cy3-CB[7] from guest-labeled proteins on the cell surface, while leaving Cy3-CB[7] latched to the cytosolic proteins for spatially conditional visualization of target proteins. This work represents a non-protein-based bioimaging tool which has inherent advantages over the widely used protein-based techniques, thereby demonstrating the great potential of this synthetic system.
Optimal region of latching activity in an adaptive Potts model for networks of neurons
NASA Astrophysics Data System (ADS)
Abdollah-nia, Mohammad-Farshad; Saeedghalati, Mohammadkarim; Abbassian, Abdolhossein
2012-02-01
In statistical mechanics, the Potts model is a model for interacting spins with more than two discrete states. Neural networks which exhibit features of learning and associative memory can also be modeled by a system of Potts spins. A spontaneous behavior of hopping from one discrete attractor state to another (referred to as latching) has been proposed to be associated with higher cognitive functions. Here we propose a model in which both the stochastic dynamics of Potts models and an adaptive potential function are present. A latching dynamics is observed in a limited region of the noise(temperature)-adaptation parameter space. We hence suggest noise as a fundamental factor in such alternations alongside adaptation. From a dynamical systems point of view, the noise-adaptation alternations may be the underlying mechanism for multi-stability in attractor-based models. An optimality criterion for realistic models is finally inferred.
Remotely adjustable fishing jar and method for using same
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wyatt, W.B.
1992-10-20
This patent describes a method for providing a jarring force to dislodge objects stuck in well bores, the method it comprises: connecting a jarring tool between an operating string and an object in a well bore; selecting a jarring force to be applied to the object; setting the selected reference jarring force into a mechanical memory mechanism by progressively engaging a first latch body and a second latch body; retaining the reference jarring force in the mechanical memory mechanism during diminution of tensional force applied by the operating string; and initiating an upwardly directed impact force within the jarring toolmore » by increasing tensional force on the operating string to a value greater than the tensional force corresponding with the selected jarring force. This patent also describes a remotely adjustable downhole fishing jar apparatus comprising: an operating mandrel; an impact release spring; a mechanical memory mechanism; and releasable latching means.« less
Space Shuttle Tail Service Mast Concept Verification
NASA Technical Reports Server (NTRS)
Uda, R. T.
1976-01-01
Design studies and analyses were performed to describe the loads and dynamics of the space shuttle tail service masts (TSMs). Of particular interest are the motion and interaction of the umbilical carrier plate, lanyard system, vacuum jacketed hoses, latches, links, and masthead. A development test rig was designed and fabricated to obtain experimental data. The test program is designed to (1) verify the theoretical dynamics calculations, (2) prove the soundness of design concepts, and (3) elucidate problem areas (if any) in the design of mechanisms and structural components. Design, fabrication, and initiation of TSM development testing at Kennedy Space Center are described.
Dual-Latching, Solenoid-Actuated Tube Valve
NASA Technical Reports Server (NTRS)
Brudnicki, Myron J.
1993-01-01
Tube-type shutoff valve electrically positioned to open or closed state by concentric solenoid. Solenoid dual latching: it holds position until changed electrically or manually. In tube valve, central tube slides axially, closing off flow when held against seat and allowing flow when backed away from seat. Simple to balance pressure on seal between seat and sharp edge of tube. With pressure-balanced seal, only small force needed to hold valve in position, regardless of pressure acting on valve.
Door latching recognition apparatus and process
Eakle, Jr., Robert F.
2012-05-15
An acoustic door latch detector is provided in which a sound recognition sensor is integrated into a door or door lock mechanism. The programmable sound recognition sensor can be trained to recognize the acoustic signature of the door and door lock mechanism being properly engaged and secured. The acoustic sensor will signal a first indicator indicating that proper closure was detected or sound an alarm condition if the proper acoustic signature is not detected within a predetermined time interval.
Remote Munitions Deployment from an Unmanned Ground Vehicle
2011-08-09
pack in a series of toe lugs. Then the rear of the pack is pushed downward over a novel spring-loaded latch /release mechanism, remaining locked in...Mason, Patrick R. Griffin, Charles E. Dean Page 4 of 5 UNCLASSIFIED developments and testing, it is not secured by a latch /release mechanism...However, the locating tabs act to wedge the pack in place while still allowing it to pull free during launch. Figure 6: Munitions secured and
The Uyghur Movement: China’s Insurgency in Xinjiang
2010-05-01
secessionist demands provide potential allies, because poverty and human rights abuses provide causes that al Qaeda organizers can latch on to and use to... wedge between the government and the population. Under Jin’s rule, corruption worsened and the economy further degraded. In one account, it was...Conversely, it is clear, however, that China has latched on to the U.S. led global war on terrorism as a means to operate outside of the confines of
Nonlinear interferometry approach to photonic sequential logic
NASA Astrophysics Data System (ADS)
Mabuchi, Hideo
2011-10-01
Motivated by rapidly advancing capabilities for extensive nanoscale patterning of optical materials, I propose an approach to implementing photonic sequential logic that exploits circuit-scale phase coherence for efficient realizations of fundamental components such as a NAND-gate-with-fanout and a bistable latch. Kerr-nonlinear optical resonators are utilized in combination with interference effects to drive the binary logic. Quantum-optical input-output models are characterized numerically using design parameters that yield attojoule-scale energy separation between the latch states.
Connector systems for structures
NASA Technical Reports Server (NTRS)
Lupo, Christian (Inventor); Evenson, Erik (Inventor); Wesselski, Clarence (Inventor)
1993-01-01
A releasable coupling device for connecting two members to one another where a collet type fastener has normally retracted latching fingers insertable into a latching recess and a longitudinally movable expander for activating the fastener is described. The longitudinal movement is retained with a paraffin actuated system which can reset. The longitudinal movement of the expander in one direction is through a one way threaded ratchet system which provides an automatic locking action and the expander is movable in either direction by an independently operated threaded action.
Heritage Adoption Lessons Learned: Cover Deployment and Latch Mechanism
NASA Technical Reports Server (NTRS)
Wincentsen, James
2006-01-01
Within JPL, there is a technology thrust need to develop a larger Cover Deployment and Latch Mechanism (CDLM) for future missions. The approach taken was to adopt and scale the CDLM design as used on the Galaxy Evolution Explorer (GALEX) project. The three separate mechanisms that comprise the CDLM will be discussed in this paper in addition to a focus on heritage adoption lessons learned and specific examples. These lessons learned will be valuable to any project considering the use of heritage designs.
Application of the ADAMS program to deployable space truss structures
NASA Technical Reports Server (NTRS)
Calleson, R. E.
1985-01-01
The need for a computer program to perform kinematic and dynamic analyses of large truss structures while deploying from a packaged configuration in space led to the evaluation of several existing programs. ADAMS (automatic dynamic analysis of mechanical systems), a generalized program from performing the dynamic simulation of mechanical systems undergoing large displacements, is applied to two concepts of deployable space antenna units. One concept is a one cube folding unit of Martin Marietta's Box Truss Antenna and the other is a tetrahedral truss unit of a Tetrahedral Truss Antenna. Adequate evaluation of dynamic forces during member latch-up into the deployed configuration is not yet available from the present version of ADAMS since it is limited to the assembly of rigid bodies. Included is a method for estimating the maximum bending stress in a surface member at latch-up. Results include member displacement and velocity responses during extension and an example of member bending stresses at latch-up.
Single Event Effect Testing of the Analog Devices ADV212
NASA Technical Reports Server (NTRS)
Wilcox, Ted; Campola, Michael; Kadari, Madhu; Nadendla, Seshagiri R.
2017-01-01
The Analog Devices ADV212 was initially tested for single event effects (SEE) at the Texas AM University Cyclotron Facility (TAMU) in July of 2013. Testing revealed a sensitivity to device hang-ups classified as single event functional interrupts (SEFI), soft data errors classified as single event upsets (SEU), and, of particular concern, single event latch-ups (SEL). All error types occurred so frequently as to make accurate measurements of the exposure time, and thus total particle fluence, challenging. To mitigate some of the risk posed by single event latch-ups, circuitry was added to the electrical design to detect a high current event and automatically recycle power and reboot the device. An additional heavy-ion test was scheduled to validate the operation of the recovery circuitry and the continuing functionality of the ADV212 after a substantial number of latch-up events. As a secondary goal, more precise data would be gathered by an improved test method, described in this test report.
A micromechanical expanding coil mechanism for in vivo magnetic resonance imaging
NASA Astrophysics Data System (ADS)
Ichiki, M.; Syms, R. R. A.; Young, I. R.
2005-04-01
A mechanism for an expanding coil designed for use for in vivo magnetic resonance imaging is demonstrated. The mechanism has a small (1 mm) cross-sectional width, and may therefore be passed through a tubular orifice such as the endoscope channel used for accessing a bile duct. Once in place, the coil may be deformed by controlled in-plane buckling and fixed in this state by a rack-and-tooth latch. The latch may be released to return the mechanism to its original state for withdrawal. A simple analytic model of the device is developed using Euler bending theory. Prototypes are fabricated in bonded silicon-on-insulator material by deep reactive ion etching and undercut. Expansion and latching are demonstrated, and performance characteristics are found to be in good agreement with the theoretical models. A lateral expansion of 1 mm was routinely achieved on either side of a device with an initial width of 1 mm (corresponding to a three-fold expansion) using an axial compression of 400 µm.
CryoEM structure of the mature dengue virus at 3.5-Å resolution
Zhang, Xiaokang; Ge, Peng; Yu, Xuekui; Brannan, Jennifer M.; Bi, Guoqiang; Zhang, Qinfen; Schein, Stan; Zhou, Z. Hong
2012-01-01
Regulated by pH, membrane-anchored proteins E and M play a series of roles during dengue virus maturation and membrane fusion. Our atomic model of the whole virion from cryo electron microscopy at 3.5Å resolution reveals that in the mature virus at neutral extracellular pH, the N-terminal 20-amino acid segment of M (involving three pH-sensing histidines) latches and thereby prevents spring-loaded E fusion protein from prematurely exposing its fusion peptide. This M latch was fastened at an earlier stage, during maturation at acid pH in the trans-Golgi network. At a later stage, to initiate infection in response to acid pH in the late endosome, M releases the latch and exposes the fusion peptide. Thus, M serves as a multistep chaperone of E to control the conformational changes accompanying maturation and infection. These pH-sensitive interactions could serve as targets for drug discovery. PMID:23241927
Pounds, Lea; Fisher, Christopher M; Barnes-Josiah, Debora; Coleman, Jason D; Lefebvre, R Craig
Support of others is a key factor for mothers who choose to breastfeed their infants, including those who balance work outside the home and breastfeeding. However, little research has been done to understand how maternal support during the postpartum period impacts mothers' ability to later balance work and breastfeeding, in particular full-time work and exclusive breastfeeding. The results of this qualitative study indicate that the timing of support plays a key role in mothers' ability to successfully overcome barriers during the early postpartum period, thus building maternal self-efficacy in addressing problems encountered when they return to work. To understand the experience of low-income women who successfully balance full-time work and exclusive breastfeeding for the recommended 6 months, interviews were conducted with women who met study criteria for income level, work status, and exclusive breastfeeding. Breastfeeding peer counselors were also interviewed as key informants. Interviews were recorded, transcribed, and coded for themes. The results of both sets of interviews were triangulated with a focused literature review to assure the soundness of the qualitative analysis. Timing of support included acute support, such as help establishing a successful latch needed during the first 2 weeks after delivery, to deal with breastfeeding problems that mothers perceived as being mentally and emotionally overwhelming and longer-term support needed to overcome problems perceived as being less intense. The research invites further exploration into the relationship between breastfeeding support provided by mothers' support system, including healthcare professionals, during the postpartum period and rates of breastfeeding duration and exclusivity.
Hua, Zhishan; Pal, Rohit; Srivannavit, Onnop; Burns, Mark A; Gulari, Erdogan
2008-03-01
This paper presents a novel optically addressed microactuator array (microfluidic "flash memory") with latched operation. Analogous to the address-data bus mediated memory address protocol in electronics, the microactuator array consists of individual phase-change based actuators addressed by localized heating through focused light patterns (address bus), which can be provided by a modified projector or high power laser pointer. A common pressure manifold (data bus) for the entire array is used to generate large deflections of the phase change actuators in the molten phase. The use of phase change material as the working media enables latched operation of the actuator array. After the initial light "writing" during which the phase is temporarily changed to molten, the actuated status is self-maintained by the solid phase of the actuator without power and pressure inputs. The microfluidic flash memory can be re-configured by a new light illumination pattern and common pressure signal. The proposed approach can achieve actuation of arbitrary units in a large-scale array without the need for complex external equipment such as solenoid valves and electrical modules, which leads to significantly simplified system implementation and compact system size. The proposed work therefore provides a flexible, energy-efficient, and low cost multiplexing solution for microfluidic applications based on physical displacements. As an example, the use of the latched microactuator array as "normally closed" or "normally open" microvalves is demonstrated. The phase-change wax is fully encapsulated and thus immune from contamination issues in fluidic environments.
Locking mechanism for orthopedic braces
NASA Technical Reports Server (NTRS)
I-Lechao, J.; Epps, C. H., Jr. (Inventor)
1976-01-01
A locking mechanism for orthopedic braces is described which automatically prevents or permits the relative pivotable movement between a lower brace member and an upper brace member. The upper and lower brace members are provided with drilled bores within which a slidable pin is disposed, and depending upon the inclination of the brace members with respect to a vertical plane, the slidable pin will be interposed between both brace members. The secondary or auxiliary latching device includes a spring biased, manually operable lever bar arrangement which is manually unlatched and automatically latched under the influence of the spring.
Micro environmental sensing device
Polosky, Marc A.; Lukens, Laurance L.
2006-05-02
A microelectromechanical (MEM) acceleration switch is disclosed which includes a proof mass flexibly connected to a substrate, with the proof mass being moveable in a direction substantially perpendicular to the substrate in response to a sensed acceleration. An electrode on the proof mass contacts one or more electrodes located below the proof mass to provide a switch closure in response to the sensed acceleration. Electrical latching of the switch in the closed position is possible with an optional latching electrode. The MEM acceleration switch, which has applications for use as an environmental sensing device, can be fabricated using micromachining.
2009-05-28
posts use a small sliding “ latch ” to insure they remain in place (Appendix 2, Figure 4). AFPTEF Report No. 09-R-02 USMC CCP AFPTEF Project No. 09...A total of 8 inflated air bladders, measuring 30 in. x 30 in. before inflation, shall be wedged between the end panel and each shelf load, and the...sliding “ latch ”. AFPTEF Report No. 09-R-02 USMC CCP AFPTEF Project No. 09-P-104 25 Figure 5. Corner post indexing tab and lockable slide
Design of a Multifrequency Reed-Type Shock Gage With an Inertia-Operated Trigger
1949-05-01
SSBärl=^isä&^^^^^^^Z^^^mSSSn^ •RAPE£LHQLDIUG PLATE.- SEED CDiÜMM_SKAE PÄPEP"C*£I:AMP^-, / SHAFTS SPACEß COMPEESSION OI?WE SPEIW PAPEB HOIOEE LATCH ...which wedges it against a sta- tionary plate located opposite the ratchet. Operation of Gage After the gage is mounted on the structure to be...clamping nut, waxed paper is inserted, and the paper holder is pulled back 2 in. by hand until it is engaged by a paper-holder latch provided at the
NASA Technical Reports Server (NTRS)
Fujimura, A.; Abe, M.; Yada, T.; Nakamura, T.; Noguchi, T.; Okazaki, R.; Ishibashi, Y.; Shirai, K.; Okada, T.; Yano, H.;
2011-01-01
Japanese spacecraft Hayabusa, which returned from near-Earth-asteroid Itokawa, successfully returned its reentry capsule to the Earth, the Woomera Prohibited Area in Australia in Jun 13th, 2010, as detailed in another paper [1]. The capsule introduced into the Planetary Material Sample Curation Facility in the Sagamihara campus of JAXA in the early morning of June 18th. Hereafter, we describe a series of processes for the returned capsule and the container to recover gas and materials in there. A transportation box of the recovered capsule was cleaned up on its outer surface beforehand and introduced into the class 10,000 clean room of the facility. Then, the capsule was extracted from the box and its plastic bag was opened and checked and photographed the outer surface of the capsule. The capsule was composed of the container, a backside ablator, a side ablator, an electronic box and a supporting frame. The container consists of an outer lid, an inner lid, a frame for latches, a container and a sample catcher, which is composed of room A and B and a rotational cylinder. After the first check, the capsule was packed in a plastic bag with N2 again, and transferred to the Chofu campus in JAXA, where the X-ray CT instrument is situated. The first X-ray CT analysis was performed on the whole returned capsule for confirming the conditions of latches and O-ring seal of the container. The analysis showed that the latches of the container should have worked normally, and that the double Orings of the container seemed to be sealed its sample catcher with no problem. After the first X-ray CT, the capsule was sent back to Sagamihara and introduced in the clean room to exclude the electronic box and the side ablator from the container by hand tools. Then the container with the backside ablator was set firmly to special jigs to fix the lid of container tightly to the container and set to a milling machine. The backside ablator was drilled by the machine to expose heads of bolts, which combined the ablator to the outer lid of the container, and after the drilling had been finished, all the bolts were unscrewed and the backside ablator was removed from the container. Then, the container was sent to the Chofu X-ray facility again to examine in detail by a micro X-ray CT instrument in order to reconfirm that the condition of the latches of the lid of container was normal and that its double O-ring seemed to have been sealed after the last X-ray CT analysis.
NASA Lessons Learned from Space Lubricated Mechanisms
NASA Technical Reports Server (NTRS)
Predmore, Roamer E.
2000-01-01
This document reviews the lessons learned from short-life and long life lubricated space mechanisms. A short-life lubricated mechanisms complete their life test qualification requirements after a few cycles. The mechanisms include the hinges, motors and bearings for deployment, release mechanisms, latches, release springs and support shops. Performance testing can be difficult and expensive but must be accomplished. A long-life lubricated mechanisms requires up to 5 years of life testing, or 10 to 100 years of successful flight. The long-life mechanisms include reaction wheels, momentum wheels, antenna gimbals, solar array drives, gyros and despin mechanisms. Several instances of how a mechanisms failed either in test, or in space use, and the lessons learned from these failures are reviewed. The effect of the movement away from CFC-113 cleaning solvent to ODC (Ozone-Depleting Chemical) -free is reviewed, and some of the alternatives are discussed.
NASA Technical Reports Server (NTRS)
Schaffnit, William O.
1997-01-01
Part of the redesign of the SRMs for the Space Shuttle involved the substitution of three new capture cylinders for three of the previously used cylinders. These new cylinders mate with the old standard case segments in each of the three field joints. The new capture cylinders contain an integral capture latch on the tang end which mates with a case clevis during stackup at KSC. The capture cylinders also contain a groove in the capture latch to provide for a third 0-ring in the joint and are designed to achieve a metal-to- metal interference fit between the capture latch and the mating clevis. An unexpected fretting problem has occurred on the tang capture feature and the inner clevis leg interference fit surfaces on flight hardware since STS-26. Varying degrees of fretting damage have been found on the case segments from different flight motors. Fretting is a wear phenomena that occurs when two tightly fitting metal surfaces are subject to cyclic relative motion of extremely small amplitudes (generally less than 0.010-inch) in the absence of adequate lubrication. It is adhesive ("cold" - welding) in nature and vibration is its essential causative factor. This problem has manifested itself on the flight motors as a series of pits and axial gouges on the inside diameter (ID) surfaces of the inner clevis legs and the outside diameter (OD) surfaces of the tang capture features. The problem occurs in varying degrees of severity in all of the field joints. It is not believed that fretting is a flight safety issue. However, it could become a reusability issue if left unattended. Fretting has been encountered in other industries for many years and measures that will prevent or reduce it have been devised. These include: elimination or reduction of vibration (amplitudes and/or frequencies), elimination of slip, improved lubrication between parts, increased surface separation, increased interference, inducing residual compressive stresses in the surfaces of the mating parts, and employing non-fretting interference shims. Looking at each of these separately; vibration and slip occur in varying degrees and magnitudes in the field joints (as part of the roll-out, launch, flight, splashdown, flotation, and/or tow back) and are difficult to define or eliminate. Improved lubrication is something that was evaluated since it would be the simplest change to incorporate, but little or no improvement was found. Increasing surface separation would defeat the purpose of the interference fit. The effect of increasing the interference fit is unknown. Additional shot peening and/or surface rolling to impart residual compressive stresses in the joints undoubtedly would alter the characteristics and finish of the sealing surfaces of the motor cases. Also, experimental data' indicate that the tangs and clevises already have residual compressive stress fields on their surfaces yet fretting occurs. These stresses probably result from the case machining and the glass beading used to clean these surfaces.
Skoda, George I.
1989-01-01
A depressurization valve for use in relieving completely the pressure in a simplified boiling water reactor is disclosed. The normally closed and sealed valve is provided with a valve body defining a conduit from an outlet of a manifold from the reactor through a valve seat. A closing valve disk is configured for fitting to the valve seat to normally close the valve. The seat below the disk is provided with a radially extending annulus extending a short distance into the aperture defined by the seat. The disk is correspondingly provided with a longitudinally extending annulus that extends downwardly through the aperture defined by the seat towards the high pressure side of the valve body. A ring shaped membrane is endlessly welded to the seat annulus and to the disk annulus. The membrane is conformed over the confronted surface of the seat and disk in a C-sectioned configuration to seal the depressurization valve against the possibility of weeping. The disk is held to the closed position by an elongate stem extending away from the high pressure side of the valve body. The stem has a flange configured integrally to the stem for bias by two springs. The first spring acts from a portion of the housing overlying the disk on the stem flange adjacent the disk. This spring urges the stem and attached disk away from the seat and thus will cause the valve to open at any pressure. A second spring--preferably of the Belleville variety--acts on a latch plate surrounding and freely moving relative to the end of the stem. This second spring overcomes the bias of the first spring and any pressure acting upon the disk. This Belleville spring maintains through its spring force the valve in the closed position. At the same time, the latch plate with its freedom of movement relative to the stem allows the stem to thermally expand during valve temperature excursion. The latch plate in surrounding the stem is limited in its outward movement by a boss attached to the stem at the end of the stem remote from the disk. The latch plate is held normally closed by three radial latches spaced at 120.degree. around the periphery of the plate.
Kanwal, Jagmeet S; Medvedev, Andrei V; Micheyl, Christophe
2003-08-01
During navigation and the search phase of foraging, mustached bats emit approximately 25 ms long echolocation pulses (at 10-40 Hz) that contain multiple harmonics of a constant frequency (CF) component followed by a short (3 ms) downward frequency modulation. In the context of auditory stream segregation, therefore, bats may either perceive a coherent pulse-echo sequence (PEPE...), or segregated pulse and echo streams (P-P-P... and E-E-E...). To identify the neural mechanisms for stream segregation in bats, we developed a simple yet realistic neural network model with seven layers and 420 nodes. Our model required recurrent and lateral inhibition to enable output nodes in the network to 'latch-on' to a single tone (corresponding to a CF component in either the pulse or echo), i.e., exhibit differential suppression by the alternating two tones presented at a high rate (> 10 Hz). To test the applicability of our model to echolocation, we obtained neurophysiological data from the primary auditory cortex of awake mustached bats. Event-related potentials reliably reproduced the latching behaviour observed at output nodes in the network. Pulse as well as nontarget (clutter) echo CFs facilitated this latching. Individual single unit responses were erratic, but when summed over several recording sites, they also exhibited reliable latching behaviour even at 40 Hz. On the basis of these findings, we propose that a neural correlate of auditory stream segregation is present within localized synaptic activity in the mustached bat's auditory cortex and this mechanism may enhance the perception of echolocation sounds in the natural environment.
An 8 bit 1 MS/s SAR ADC with 7.72-ENOB
NASA Astrophysics Data System (ADS)
Duan, Jihai; Zhu, Zhiyong; Deng, Jinli; Xu, Weilin
2017-08-01
This paper presents a low power 8-bit 1 MS/s SAR ADC with 7.72-bit ENOB. Without an op-amp, an improved segmented capacitor DAC is proposed to reduce the capacitance and the chip area. A dynamic latch comparator with output offset voltage storage technology is used to improve the precision. Adding an extra positive feedback in the latch is to increase the speed. What is more, two pairs of CMOS switches are utilized to eliminate the kickback noise introduced by the latch. The proposed SAR ADC was fabricated in SMIC 0.18 {{μ }}{{m}} CMOS technology. The measured results show that this design achieves an SFDR of 61.8 dB and an ENOB of 7.72 bits, and it consumes 67.5 μW with the FOM of 312 fJ/conversion-step at 1 MS/s sample under 1.8 V power supply. Project supported by the National Natural Science Foundation of China (Nos. 61161003, 61264001, 61166004) and the Guangxi Key Laboratory of Precision Navigation Technology and Application Foundation (No. DH201501).
Molecular quantum cellular automata cell design trade-offs: latching vs. power dissipation.
Rahimi, Ehsan; Reimers, Jeffrey R
2018-06-20
The use of molecules to enact quantum cellular automata (QCA) cells has been proposed as a new way for performing electronic logic operations at sub-nm dimensions. A key question that arises concerns whether chemical or physical processes are to be exploited. The use of chemical reactions allows the state of a switch element to be latched in molecular form, making the output of a cell independent of its inputs, but costs energy to do the reaction. Alternatively, if purely electronic polarization is manipulated then no internal latching occurs, but no power is dissipated provided the fields from the inputs change slowly compared to the molecular response times. How these scenarios pan out is discussed by considering calculated properties of the 1,4-diallylbutane cation, a species often used as a paradigm for molecular electronic switching. Utilized are results from different calculation approaches that depict the ion either as a charge-localized mixed-valence compound functioning as a bistable switch, or else as an extremely polarizable molecule with a delocalized electronic structure. Practical schemes for using molecular cells in QCA and other devices emerge.
DEVICE FOR CONTROLLING INSERTION OF ROD
Beaty, B.J.
1958-10-14
A device for rapidly inserting a safety rod into a nuclear reactor upon a given signal or in the event of a power failure in order to prevent the possibility of extensive damage caused by a power excursion is described. A piston is slidably mounted within a vertical cylinder with provision for an electromagnetic latch at the top of the cylinder. This assembly, with a safety rod attached to the piston, is mounted over an access port to the core region of the reactor. The piston is normally latched at the top of the cylinder with the safety rod clear of the core area, however, when the latch is released, the piston and rod drop by their own weight to insert the rod. Vents along the side of the cylinder permit the escape of the air entrapped under the piston over the greater part of the distance, however, at the end of the fall the entrapped air is compressed thereby bringing the safety rod gently to rest, thus providing for a rapid automatic insertion of the rod with a minimum of structural shock.
Garcia, Ernest J; Polosky, Marc A
2013-05-21
An optical switch reliably maintains its on or off state even when subjected to environments where the switch is bumped or otherwise moved. In addition, the optical switch maintains its on or off state indefinitely without requiring external power. External power is used only to transition the switch from one state to the other. The optical switch is configured with a fixed optical fiber and a movable optical fiber. The movable optical fiber is guided by various actuators in conjunction with a latching mechanism that configure the switch in one position that corresponds to the on state and in another position that corresponds to the off state.
PEPC LRU: Ball Support Assembly
DOE Office of Scientific and Technical Information (OSTI.GOV)
Alger, T
1999-05-14
The PEPC LRU upper ball support assembly consists of a ball and a pneumatic air cylinder/conical seat latching mechanism to be attached to the optics support frame,and a ball attached to the PEPC LRU. Both components are designed to allow manual positioning in three axes. Upon insertion of the PEPC LRU into the structure, the upper pneumatic cylinder is actuated to latch the two assemblies together through the conical seat device to grab the lower ball to support the LRU weight. To be conservative, the design load for the assembly is 1500 pounds (the prototype PEPC LRU weight was measuredmore » to be near 1380 pounds).« less
NASA Technical Reports Server (NTRS)
Buehler, Martin G. (Inventor); Nixon, Robert H. (Inventor); Soli, George A. (Inventor); Blaes, Brent R. (Inventor)
1995-01-01
A method for predicting the SEU susceptibility of a standard-cell D-latch using an alpha-particle sensitive SRAM, SPICE critical charge simulation results, and alpha-particle interaction physics. A technique utilizing test structures to quickly and inexpensively characterize the SEU sensitivity of standard cell latches intended for use in a space environment. This bench-level approach utilizes alpha particles to induce upsets in a low LET sensitive 4-k bit test SRAM. This SRAM consists of cells that employ an offset voltage to adjust their upset sensitivity and an enlarged sensitive drain junction to enhance the cell's upset rate.
NASA Technical Reports Server (NTRS)
1991-01-01
The Model 1150 electronic spring latch, which provides controlled and timed access to a safe, was developed by Burnett Electronics Lab, Inc., San Diego, CA, and is marketed by KeyOne, Inc. also of San Diego. The Model 1150 is a spinoff from a spinoff. The original spinoff, the acoustic pinger, is an underwater transmitting device developed by Langley Research Center and the Navy for location and recovery of sounding rocket research payloads from the ocean. Long functioning life is a vital requirement for both the acoustic pinger and the Model 1150. The electronic spring latch employs the pinger power management technology to get long life out of the battery power source.
Peterson, L
1984-01-01
I evaluated the influence of two training manuals on latch-key children's acquisition of home safety and survival skills. The widely used, discussion-oriented "Prepared for Today" manual was compared with a behaviorally oriented "Safe at Home" manual. Data were scored by response criteria developed by experts and by parents' and experts' ratings of children's spontaneous answers. With both methods of scoring, three behaviorally trained children demonstrated clear and abrupt increases in skill following training in each of seven trained modules, and these increases largely persisted in real world generalization probes and at 5-month follow-up. Smaller and less stable increases in skill were found in the three discussion-trained children across the seven modules; lower skill levels were also seen in real world generalization probes and at follow-up. Neither group of children demonstrated skill increases in home safety areas that were not explicitly trained. Both training methods produced small decreases in children's self-report of general anxiety and anxiety concerning home safety. Results are discussed in terms of their implications for cost-effective training of latch-key children. PMID:6511698
Development of a relatchable cover mechanism for a cryogenic IR-sensor
NASA Technical Reports Server (NTRS)
Birner, R.; Lange, G.; Roth, M.; Voit, A.
1991-01-01
A cover mechanism for use on the Infrared Background Signature Survey (IBSS) cryostat was developed. The IBSS IR-instrument is scheduled for STS launch in early 1991 as a payload of the Shuttle Payload Satellite (SPS) 2. The cover is hinged, with a motorized rope drive. During ground processing, launch, entry, and landing, the cryostat, which houses the IR-instrument, is required to be a sealed vacuum tight container for cooling purposes and contamination prevention. When on orbit, the cover is opened to provide an unobstructed field of view for the IR-instrument. A positive seal is accomplished through the use of latch mechanism. The cover and the latch are driven by a common redundant actuator consisting of dc motors, spur gears, and a differential gear. Hall probe limit switches and position sensors (rotary variable transformer) are used to determine the position of the cover and the latch. The cover mechanism was successfully qualified for thermal vacuum (-25 to 35 C), acoustic noise, vibration (6 Gs sine, 9.7 G RMS) and life cycles. Constricting requirements, mechanical and electronic control design, specific design details, test results of functional performance, and environmental and life tests are described.
Eight-Channel Continuous Timer
NASA Technical Reports Server (NTRS)
Cole, Steven
2004-01-01
A custom laboratory electronic timer circuit measures the durations of successive cycles of nominally highly stable input clock signals in as many as eight channels, for the purpose of statistically quantifying the small instabilities of these signals. The measurement data generated by this timer are sent to a personal computer running software that integrates the measurements to form a phase residual for each channel and uses the phase residuals to compute Allan variances for each channel. (The Allan variance is a standard statistical measure of instability of a clock signal.) Like other laboratory clock-cycle-measuring circuits, this timer utilizes an externally generated reference clock signal having a known frequency (100 MHz) much higher than the frequencies of the input clock signals (between 100 and 120 Hz). It counts the number of reference-clock cycles that occur between successive rising edges of each input clock signal of interest, thereby affording a measurement of the input clock-signal period to within the duration (10 ns) of one reference clock cycle. Unlike typical prior laboratory clock-cycle-measuring circuits, this timer does not skip some cycles of the input clock signals. The non-cycle-skipping feature is an important advantage because in applications that involve integration of measurements over long times for characterizing nominally highly stable clock signals, skipping cycles can degrade accuracy. The timer includes a field-programmable gate array that functions as a 20-bit counter running at the reference clock rate of 100 MHz. The timer also includes eight 20-bit latching circuits - one for each channel - at the output terminals of the counter. Each transition of an input signal from low to high causes the corresponding latching circuit to latch the count at that instant. Each such transition also sets a status flip-flop circuit to indicate the presence of the latched count. A microcontroller reads the values of all eight status flipflops and then reads the latched count for each channel for which the flip-flop indicates the presence of a count. Reading the count for each channel automatically causes the flipflop of that channel to be reset. The microcontroller places the counts in time order, identifies the channel number for each count, and transmits these data to the personal computer.
Driving and latching of the Starlab pointing mirror doors
NASA Technical Reports Server (NTRS)
Beaven, Herbert R., Jr.; Avina, Raymond R.
1990-01-01
The Starlab Experiment, a major SDIO technology initiative, is an attached payload which will be delivered into Earth orbit aboard NASA's Space Shuttle in 1991. Starlab will generate and aim an 80 cm diameter laser beam into space through a large opening in the structure which houses the pointing mirror. Two doors, each somewhat larger than a desktop, cover the opening when the laser optics system is nonoperational. Latch Mechanism Assemblies hold the doors shut during liftoff and ascent and, again, during Orbiter reentry. Each door is powered by a Door Drive System during the many open/close cycles between various experiments. The design, testing, and resultant failure modes of these mechanisms are examined.
Clock Controller For Ac Self-Timing Analysis Of Logic System
Lo, Tinchee; Flanagan, John D.
2004-05-18
A clock controller and clock generating method are provided for AC self-test timing analysis of a logic system. The controller includes latch circuitry which receives a DC input signal at a data input, and a pair of continuous out-of-phase clock signals at capture and launch clock inputs thereof. The latch circuitry outputs two overlapping pulses responsive to the DC input signal going high. The two overlapping pulses are provided to waveform shaper circuitry which produces therefrom two non-overlapping pulses at clock speed of the logic system to be tested. The two non-overlapping pulses are a single pair of clock pulses which facilitate AC self-test timing analysis of the logic system.
Rotational MEMS mirror with latching arm for silicon photonics
NASA Astrophysics Data System (ADS)
Brière, Jonathan; Beaulieu, Philippe-Olivier; Saidani, Menouer; Nabki, Frederic; Menard, Michaël.
2015-02-01
We present an innovative rotational MEMS mirror that can control the direction of propagation of light beams inside of planar waveguides implemented in silicon photonics. Potential applications include but are not limited to optical telecommunications, medical imaging, scan and spectrometry. The mirror has a half-cylinder shape with a radius of 300 μm that provides low and constant optical losses over the full angular displacement range. A circular comb drive structure is anchored such that it allows free or latched rotation experimentally demonstrated over 8.5° (X-Y planar rotational movement) using 290V electrostatic actuation. The entire MEMS structure was implemented using the MEMSCAP SOIMUMPs process. The center of the anchor beam is designed to be the approximate rotation point of the circular comb drive to counter the rotation offset of the mirror displacement. A mechanical characterization of the MEMS mirror is presented. The latching mechanism provides up to 20 different angular locking positions allowing the mirror to counter any resonance or vibration effects and it is actuated with an electrostatic linear comb drive. An innovative gap closing structure was designed to reduce optical propagation losses due to beam divergence in the interstitial space between the mirror and the planar waveguide. The gap closing structure is also electrostatically actuated and includes two side stoppers to prevent stiction.
Placement of clock gates in time-of-flight optoelectronic circuits
NASA Astrophysics Data System (ADS)
Feehrer, John R.; Jordan, Harry F.
1995-12-01
Time-of-flight synchronized optoelectronic circuits capitalize on the highly controllable delays of optical waveguides. Circuits have no latches; synchronization is achieved by adjustment of the lengths of waveguides that connect circuit elements. Clock gating and pulse stretching are used to restore timing and power. A functional circuit requires that every feedback loop contain at least one clock gate to prevent cumulative timing drift and power loss. A designer specifies an ideal circuit, which contains no or very few clock gates. To make the circuit functional, we must identify locations in which to place clock gates. Because clock gates are expensive, add area, and increase delay, a minimal set of locations is desired. We cast this problem in graph-theoretical form as the minimum feedback edge set problem and solve it by using an adaptation of an algorithm proposed in 1966 [IEEE Trans. Circuit Theory CT-13, 399 (1966)]. We discuss a computer-aided-design implementation of the algorithm that reduces computational complexity and demonstrate it on a set of circuits.
Microelectromechanical acceleration-sensing apparatus
Lee, Robb M [Albuquerque, NM; Shul, Randy J [Albuquerque, NM; Polosky, Marc A [Albuquerque, NM; Hoke, Darren A [Albuquerque, NM; Vernon, George E [Rio Rancho, NM
2006-12-12
An acceleration-sensing apparatus is disclosed which includes a moveable shuttle (i.e. a suspended mass) and a latch for capturing and holding the shuttle when an acceleration event is sensed above a predetermined threshold level. The acceleration-sensing apparatus provides a switch closure upon sensing the acceleration event and remains latched in place thereafter. Examples of the acceleration-sensing apparatus are provided which are responsive to an acceleration component in a single direction (i.e. a single-sided device) or to two oppositely-directed acceleration components (i.e. a dual-sided device). A two-stage acceleration-sensing apparatus is also disclosed which can sense two acceleration events separated in time. The acceleration-sensing apparatus of the present invention has applications, for example, in an automotive airbag deployment system.
Mechanized fluid connector and assembly tool system with ball detents
NASA Technical Reports Server (NTRS)
Zentner, Ronald C. (Inventor); Smith, Steven A. (Inventor)
1991-01-01
A fluid connector system is disclosed which includes a modified plumbing union having a rotatable member for drawing said union into a fluid tight condition. A drive tool is electric motor actuated and includes a reduction gear train providing an output gear engaging an integral peripheral spur gear on the rotatable member. Coaxial alignment means are attached to both the connector assembly and the drive tool. A hand lever actuated latching system includes a plurality of circumferentially spaced latching balls selectively wedged against the alignment means attached to the connector assembly or to secure the drive tool with its output gear in mesh with the integral peripheral spur gear. The drive motor is torque, speed, and direction controllable.
Design of a mercury Propellant Storage and Distribution assembly
NASA Technical Reports Server (NTRS)
Holcomb, L. B.; Womack, J. R.
1973-01-01
A study has been conducted of a Propellant Storage and Distribution (PSD) assembly for a solar electric propulsion (SEP) thrust subsystem. As a result of the trade-off study an elastomeric diaphragm propellant tank with nitrogen blowdown pressurization was the method selected for propellant expulsion. This study included the following propellant management devices: surface tension, metallic bellows, and metallic and elastomeric diaphragms. Pressurant supply concepts investigated were blowdown, externally pressure regulated, vaporizing Freon 113, and heated CO2/Zeolite. The configuration selected consists of a single propellant tank, a single main propellant latching-solenoid valve, and individual thruster latching-solenoid valves. Stainless steel was the selected tankage material and AF-E-332 was the selected diaphragm material. The PSD design characteristics and interfaces are summarized.
Designing berthing mechanisms for international compatibility
NASA Technical Reports Server (NTRS)
Winch, John; Gonzalez-Vallejo, Juan J.
1991-01-01
The paper examines the technological issues regarding common berthing interfaces for the Space Station Freedom and pressurized modules from U.S., European, and Japanese space programs. The development of the common berthing mechanism (CBM) is based on common requirements concerning specifications, launch environments, and the unique requirements of ESA's Man-Tended Free Flyer. The berthing mechanism is composed of an active and a passive half, a remote manipulator system, 4 capture-latch assemblies, 16 structural bolts, and a pressure gage to verify equalization. Extensive graphic and verbal descriptions of each element are presented emphasizing the capture-latch motion and powered-bolt operation. The support systems to complete the interface are listed, and the manufacturing requirements for consistent fabrication are discussed to ensure effective international development.
Design Techniques for Power-Aware Combinational Logic SER Mitigation
NASA Astrophysics Data System (ADS)
Mahatme, Nihaar N.
The history of modern semiconductor devices and circuits suggests that technologists have been able to maintain scaling at the rate predicted by Moore's Law [Moor-65]. With improved performance, speed and lower area, technology scaling has also exacerbated reliability issues such as soft errors. Soft errors are transient errors that occur in microelectronic circuits due to ionizing radiation particle strikes on reverse biased semiconductor junctions. These radiation induced errors at the terrestrial-level are caused due to radiation particle strikes by (1) alpha particles emitted as decay products of packing material (2) cosmic rays that produce energetic protons and neutrons, and (3) thermal neutrons [Dodd-03], [Srou-88] and more recently muons and electrons [Ma-79] [Nara-08] [Siew-10] [King-10]. In the space environment radiation induced errors are a much bigger threat and are mainly caused by cosmic heavy-ions, protons etc. The effects of radiation exposure on circuits and measures to protect against them have been studied extensively for the past 40 years, especially for parts operating in space. Radiation particle strikes can affect memory as well as combinational logic. Typically when these particles strike semiconductor junctions of transistors that are part of feedback structures such as SRAM memory cells or flip-flops, it can lead to an inversion of the cell content. Such a failure is formally called a bit-flip or single-event upset (SEU). When such particles strike sensitive junctions part of combinational logic gates they produce transient voltage spikes or glitches called single-event transients (SETs) that could be latched by receiving flip-flops. As the circuits are clocked faster, there are more number of clocking edges which increases the likelihood of latching these transients. In older technology generations the probability of errors in flip-flops due to SETs being latched was much lower compared to direct strikes on flip-flops or SRAMs leading to SEUs. This was mainly because the operating frequencies were much lower for older technology generations. The Intel Pentium II for example was fabricated using 0.35 microm technology and operated between 200-330 MHz. With technology scaling however, operating frequencies have increased tremendously and the contribution of soft errors due to latched SETs from combinational logic could account for a significant proportion of the chip-level soft error rate [Sief-12][Maha-11][Shiv02] [Bu97]. Therefore there is a need to systematically characterize the problem of combinational logic single-event effects (SEE) and understand the various factors that affect the combinational logic single-event error rate. Just as scaling has led to soft errors emerging as a reliability-limiting failure mode for modern digital ICs, the problem of increasing power consumption has arguably been a bigger bane of scaling. While Moore's Law loftily states the blessing of technology scaling to be smaller and faster transistor it fails to highlight that the power density increases exponentially with every technology generation. The power density problem was partially solved in the 1970's and 1980's by moving from bipolar and GaAs technologies to full-scale silicon CMOS technologies. Following this however, technology miniaturization that enabled high-speed, multicore and parallel computing has steadily increased the power density and the power consumption problem. Today minimizing the power consumption is as much critical for power hungry server farms as it for portable devices, all pervasive sensor networks and future eco-bio-sensors. Low-power consumption is now regularly part of design philosophies for various digital products with diverse applications from computing to communication to healthcare. Thus designers in today's world are left grappling with both a "power wall" as well as a "reliability wall". Unfortunately, when it comes to improving reliability through soft error mitigation, most approaches are invariably straddled with overheads in terms of area or speed and more importantly power. Thus, the cost of protecting combinational logic through the use of power hungry mitigation approaches can disrupt the power budget significantly. Therefore there is a strong need to develop techniques that can provide both power minimization as well as combinational logic soft error mitigation. This dissertation, advances hitherto untapped opportunities to jointly reduce power consumption and deliver soft error resilient designs. Circuit as well as architectural approaches are employed to achieve this objective and the advantages of cross-layer optimization for power and soft error reliability are emphasized.
NASA Technical Reports Server (NTRS)
Appleberry, W. T.
1980-01-01
Rotary sequencer is assembled from conventional planetary differential gearset and latching mechanism utilizing inputs and outputs which are coaxial. Applications include automated production-line equipment in home appliances and in vehicles.
The 23rd Aerospace Mechanisms Symposium
NASA Technical Reports Server (NTRS)
1989-01-01
Technological areas covered include space lubrication, bearings, aerodynamic devices, spacecraft latches, deployment, positioning, and pointing. Devices for Space Station docking and manipulator and teleoperator mechanisms are also described.
Smart tunnel: Docking mechanism
NASA Technical Reports Server (NTRS)
Schliesing, John A. (Inventor); Edenborough, Kevin L. (Inventor)
1989-01-01
A docking mechanism is presented for the docking of a space vehicle to a space station comprising a flexible tunnel frame structure which is deployable from the space station. The tunnel structure comprises a plurality of series connected frame sections, one end section of which is attached to the space station and the other end attached to a docking module of a configuration adapted for docking in the payload bay of the space vehicle. The docking module is provided with trunnions, adapted for latching engagement with latches installed in the vehicle payload bay and with hatch means connectable to a hatch of the crew cabin of the space vehicle. Each frame section comprises a pair of spaced ring members, interconnected by actuator-attenuator devices which are individually controllable by an automatic control means to impart relative movement of one ring member to the other in six degrees of freedom of motion. The control means includes computer logic responsive to sensor signals of range and attitude information, capture latch condition, structural loads, and actuator stroke for generating commands to the onboard flight control system and the individual actuator-attenuators to deploy the tunnel to effect a coupling with the space vehicle and space station after coupling. A tubular fluid-impervious liner, preferably fabric, is disposed through the frame sections of a size sufficient to accommodate the passage of personnel and cargo.
Method and Apparatus for Reducing the Vulnerability of Latches to Single Event Upsets
NASA Technical Reports Server (NTRS)
Shuler, Robert L., Jr. (Inventor)
2002-01-01
A delay circuit includes a first network having an input and an output node, a second network having an input and an output, the input of the second network being coupled to the output node of the first network. The first network and the second network are configured such that: a glitch at the input to the first network having a length of approximately one-half of a standard glitch time or less does not cause the voltage at the output of the second network to cross a threshold, a glitch at the input to the first network having a length of between approximately one-half and two standard glitch times causes the voltage at the output of the second network to cross the threshold for less than the length of the glitch, and a glitch at the input to the first network having a length of greater than approximately two standard glitch times causes the voltage at the output of the second network to cross the threshold for approximately the time of the glitch. The method reduces the vulnerability of a latch to single event upsets. The latch includes a gate having an input and an output and a feedback path from the output to the input of the gate. The method includes inserting a delay into the feedback path and providing a delay in the gate.
Method and Apparatus for Reducing the Vulnerability of Latches to Single Event Upsets
NASA Technical Reports Server (NTRS)
Shuler, Robert L., Jr. (Inventor)
2002-01-01
A delay circuit includes a first network having an input and an output node, a second network having an input and an output, the input of the second network being coupled to the output node of the first network. The first network and the second network are configured such that: a glitch at the input to the first network having a length of approximately one-half of a standard glitch time or less does not cause tile voltage at the output of the second network to cross a threshold, a glitch at the input to the first network having a length of between approximately one-half and two standard glitch times causes the voltage at the output of the second network to cross the threshold for less than the length of the glitch, and a glitch at the input to the first network having a length of greater than approximately two standard glitch times causes the voltage at the output of the second network to cross the threshold for approximately the time of the glitch. A method reduces the vulnerability of a latch to single event upsets. The latch includes a gate having an input and an output and a feedback path from the output to the input of the gate. The method includes inserting a delay into the feedback path and providing a delay in the gate.
Technology development for cryogenic deployable telescope structures and mechanisms
NASA Astrophysics Data System (ADS)
Atkinson, Charles B.; Gilman, Larry; Reynolds, Paul
2003-12-01
At 6-7 meters in diameter, the James Webb Space Telescope (JWST) will require structures that remain stable to levels that are on the order of 10 nanometers under dynamic and thermal loading while operating at cryogenic temperatures. Moreover, the JWST will be the first telescope in space that is deployed, resulting in an aperture that is not only segmented, but has hinge-lines and the associated joining systems or latches in it. In order to understand the behavior and reduce the risk associated with very large, deployed structures and the stability of the associated structure and latches, we developed and tested the largest cryogenic structure ever built and then characterized its stability. This paper presents a description of the design of the Development Optical Telescope Assembly (DOTA), the testing performed, and the results of the testing performed on it. We discuss the material selection and characterization processes, give a description of the test configurations, describe the metrology equipment and the validation process for it, provide the test results, and summarize the conclusions drawn from the results. The testing and associated results include characterization of the thermal stability of the large-scale structure, characterization of the micro-dynamic stability of the latching system, and measurements of the deployment capability of the mechanisms. We also describe how the DOTA design relates to the JWST design and how the test results relate to the JWST requirements.
The 24th Aerospace Mechanisms Symposium
NASA Technical Reports Server (NTRS)
1990-01-01
The proceedings of the symposium are reported. Technological areas covered include actuators, aerospace mechanism applications for ground support equipment, lubricants, latches, connectors, and other mechanisms for large space structures.
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The 25th Aerospace Mechanisms Symposium
NASA Technical Reports Server (NTRS)
1991-01-01
Twenty-two papers are documented regarding aeronautical and spacecraft hardware. Technological areas include actuators, latches, cryogenic mechanisms, vacuum tribology, bearings, robotics, ground support equipment for aerospace applications, and other mechanisms.
Manual actuator. [for spacecraft exercising machines
NASA Technical Reports Server (NTRS)
Gause, R. L.; Glenn, C. G. (Inventor)
1974-01-01
An actuator for an exercising machine employable by a crewman aboard a manned spacecraft is presented. The actuator is characterized by a force delivery arm projected from a rotary imput shaft of an exercising machine and having a force input handle extended orthogonally from its distal end. The handle includes a hand-grip configured to be received within the palm of the crewman's hand and a grid pivotally supported for angular displacement between a first position, wherein the grid is disposed in an overlying juxtaposition with the hand-grip, and a second position, angularly displaced from the first position, for affording access to the hand-grip, and a latching mechanism fixed to the sole of a shoe worn by the crewman for latching the shoe to the grid when the grid is in the first position.
A fully redundant power hinge for LANDSAT-D appendages
NASA Technical Reports Server (NTRS)
Mamrol, F. E.; Matteo, D. N.
1981-01-01
The configuration and testing of a power driven hinge for deployment of the solar array and antenna boom for the LANDSAT-D spacecraft is discussed. The hinge is fully mechanically and electrically redundant and, thereby, can sustain a single point failure of any one motor (or its power supply), speed reducer, or bearing set without loss of its ability to function. This design utilizes the capability of the stepper motor drive to remove the flexibility of the drive train from the joint stiffness equation when the hinge is loaded against its stop. This feature precludes gapping of the joint under spacecraft maneuver loads even in the absence of a latching feature. Thus, retraction is easily accomplished by motor reversal without the need for a solenoid function to remove the latch.
Latch of HST aft shroud photographed by Electronic Still Camera
1993-12-04
S61-E-010 (4 Dec 1993) --- This close-up view of a latch on the minus V3 aft shroud door of the Hubble Space Telescope (HST) was photographed with an Electronic Still Camera (ESC), and down linked to ground controllers soon afterward. Endeavour's crew captured the HST on December 4, 1993 in order to service the telescope over a period of five days. Four of the crew members will work in alternating pairs outside Endeavour's shirt sleeve environment to service the giant telescope. Electronic still photography is a relatively new technology which provides the means for a handheld camera to electronically capture and digitize an image with resolution approaching film quality. The electronic still camera has flown as an experiment on several other shuttle missions.
Latch of HST aft shroud photographed by Electronic Still Camera
1993-12-04
S61-E-005 (4 Dec 1993) --- This close-up view of a latch on the minus V3 aft shroud door of the Hubble Space Telescope (HST) was photographed with an Electronic Still Camera (ESC), and down linked to ground controllers soon afterward. Endeavour's crew captured the HST on December 4, 1993 in order to service the telescope. Over a period of five days, four of the seven crew members will work in alternating pairs outside Endeavour's shirt sleeve environment to service the giant telescope. Electronic still photography is a relatively new technology which provides the means for a handheld camera to electronically capture and digitize an image with resolution approaching film quality. The electronic still camera has flown as an experiment on several other shuttle missions.
Latch of HST aft shroud photographed by Electronic Still Camera
1993-12-04
S61-E-004 (4 Dec 1993) --- This close-up view of a latch on the minus V3 aft shroud door of the Hubble Space Telescope (HST) was photographed with an Electronic Still Camera (ESC), and down linked to ground controllers soon afterward. Endeavour's crew captured the HST on December 4, 1993 in order to service the telescope. Over a period of five days, four of the seven crew members will work in alternating pairs outside Endeavour's shirt sleeve environment to service the giant telescope. Electronic still photography is a relatively new technology which provides the means for a handheld camera to electronically capture and digitize an image with resolution approaching film quality. The electronic still camera has flown as an experiment on several other shuttle missions.
Engineering Evaluation of International Low Impact Docking System Latch Hooks
NASA Technical Reports Server (NTRS)
Martinez, J.; Patin, R.; Figert, J.
2013-01-01
The international Low Impact Docking System (iLIDS) provides a structural arrangement that allows for visiting vehicles to dock with the International Space Station (ISS) (Fig 1). The iLIDS docking units are mechanically joined together by a series of active and passive latch hooks. In order to preserve docking capability at the existing Russian docking interfaces, the iLIDS latch hooks are required to conform to the existing Russian design. The latch hooks are classified as being fail-safe. Since the latch hooks are fail-safe, the hooks are not fracture critical and a fatigue based service life assessment will satisfy the structural integrity requirements. Constant amplitude fatigue testing to failure on four sets of active/passive iLIDS latch hooks was performed at load magnitudes of 10, 11, and 12 kips. Failure analysis of the hook fatigue failures identified multi-site fatigue initiation that was effectively centered about the hook mid-plane (consistent with the 3D model results). The fatigue crack initiation distribution implies that the fatigue damage accumulation effectively results in a very low aspect ratio surface crack (which can be simulated as thru-thickness crack). Fatigue damage progression resulted in numerous close proximity fatigue crack initiation sites. It was not possible to determine if fatigue crack coalescence occurs during cyclic loading or as result of the fast fracture response. The presence of multiple fatigue crack initiation sites on different planes will result in the formation of ratchet marks as the cracks coalesce. Once the stable fatigue crack becomes unstable and the fast fracture advances across the remaining ligament and the plane stress condition at a free-surface will result in failure along a 45 deg. shear plane (slant fracture) and the resulting inclined edge is called a shear lip. The hook thickness on the plane of fatigue crack initiation is 0.787". The distance between the shear lips on this plane was on the order of 0.48" and it was effectively centered about the mid-plane of the section. The numerous ratchet marks between the shear lips on the fracture initiation plane are indicative of multiple fatigue initiation sites within this region. The distribution of the fatigue damage about the centerline of the hook is consistent with the analytical results that demonstrate peak stress/strain response at the mid-plane that decreases in the direction of the hook outer surfaces. Scanning electron microscope images of the failed sections detected fatigue crack striations in close proximity to the free surface of the hook radius. These findings were documented at three locations on the fracture surface : 1) adjacent to the left shear lip, 2) adjacent to the right shear lip, and 3) near the centerline of the section. The features of the titanium fracture surface did not allow for a determination of a critical crack size via identification of the region where the fatigue crack propagation became unstable. The fracture based service life projections where benchmarked with strain-life analyses. The strainrange response in the hook radius was defined via the correlated finite element models and the modified method of universal slopes was incorporated to define the strain-life equation for the titanium alloy. The strain-life assessment confirmed that the fracture based projections were reasonable for the loading range of interest. Based upon the analysis and component level fatigue test data a preliminary service life capability for the iLIDS active and passive hooks of 2 lifetimes is projected (includes a scatter factor of 4).
... medlineplus.gov/ency/patientinstructions/000534.htm Storing your medicines To use the sharing features on this page, ... child latch or lock. Do not use Damaged Medicine Damaged medicine may make you sick. DO NOT ...
Code of Federal Regulations, 2011 CFR
2011-01-01
... eliminates from any hardware accessible to a child within the crib the possibility of the hardware's... foreseeable damage or abuse. (b) Locking or latching devices used to secure dropside rails shall require a...
Code of Federal Regulations, 2010 CFR
2010-01-01
... eliminates from any hardware accessible to a child within the crib the possibility of the hardware's... foreseeable damage or abuse. (b) Locking or latching devices used to secure dropside rails shall require a...
Miga Aero Actuator and 2D Machined Mechanical Binary Latch
NASA Technical Reports Server (NTRS)
Gummin, Mark A.
2013-01-01
Shape memory alloy (SMA) actuators provide the highest force-to-weight ratio of any known actuator. They can be designed for a wide variety of form factors from flat, thin packages, to form-matching packages for existing actuators. SMA actuators can be operated many thousands of times, so that ground testing is possible. Actuation speed can be accurately controlled from milliseconds to position and hold, and even electronic velocity-profile control is possible. SMA actuators provide a high degree of operational flexibility, and are truly smart actuators capable of being accurately controlled by onboard microprocessors across a wide range of voltages. The Miga Aero actuator is a SMA actuator designed specifically for spaceflight applications. Providing 13 mm of stroke with either 20- or 40-N output force in two different models, the Aero actuator is made from low-outgassing PEEK (polyether ether ketone) plastic, stainless steel, and nickel-titanium SMA wires. The modular actuator weighs less than 28 grams. The dorsal output attachment allows the Aero to be used in either PUSH or PULL modes by inverting the mounting orientation. The SPA1 actuator utilizes commercially available SMA actuator wire to provide 3/8-in. (approx. =.1 cm) of stroke at a force of over 28 lb (approx. = .125 N). The force is provided by a unique packaging of the single SMA wire that provides the output force of four SMA wires mechanically in parallel. The output load is shared by allowing the SMA wire to slip around the output attachment end to adjust or balance the load, preventing any individual wire segment from experiencing high loads during actuation. A built-in end limit switch prevents overheating of the SMA element following actuation when used in conjunction with the Miga Analog Driver [a simple MOSFET (metal oxide semiconductor field-effect transistor) switching circuit]. A simple 2D machined mechanical binary latch has been developed to complement the capabilities of SMA wire actuators. SMA actuators typically perform ideally as latch-release devices, wherein a spring-loaded device is released when the SMA actuator actuates in one direction. But many applications require cycling between two latched states open and closed.
NASA Technical Reports Server (NTRS)
Edmonds, Larry D.
1987-01-01
The steady state current distribution in a three dimensional integrated circuit is presented. A device physics approach, based on a perturbation method rather than an equivalent lumped circuit approach, is used. The perturbation method allows the various currents to be expressed in terms of elementary solutions which are solutions to very simple boundary value problems. A Simple Steady State Theory is the subtitle because the most obvious limitation of the present version of the analysis is that all depletion region boundary surfaces are treated as equipotential surfaces. This may be an adequate approximation in some applications but it is an obvious weakness in the theory when applied to latched states. Examples that illustrate the use of these analytical methods are not given because they will be presented in detail in the future.
29 CFR 1926.702 - Requirements for equipment and tools.
Code of Federal Regulations, 2012 CFR
2012-07-01
... equipped with hydraulic or pneumatic gates shall have positive safety latches or similar safety devices... cause injury, unless all potentially hazardous energy sources have been locked out and tagged. (2) Tags...
29 CFR 1926.702 - Requirements for equipment and tools.
Code of Federal Regulations, 2011 CFR
2011-07-01
... equipped with hydraulic or pneumatic gates shall have positive safety latches or similar safety devices... cause injury, unless all potentially hazardous energy sources have been locked out and tagged. (2) Tags...
29 CFR 1926.702 - Requirements for equipment and tools.
Code of Federal Regulations, 2013 CFR
2013-07-01
... equipped with hydraulic or pneumatic gates shall have positive safety latches or similar safety devices... cause injury, unless all potentially hazardous energy sources have been locked out and tagged. (2) Tags...
29 CFR 1926.702 - Requirements for equipment and tools.
Code of Federal Regulations, 2014 CFR
2014-07-01
... equipped with hydraulic or pneumatic gates shall have positive safety latches or similar safety devices... cause injury, unless all potentially hazardous energy sources have been locked out and tagged. (2) Tags...
Adaptive logical stochastic resonance in time-delayed synthetic genetic networks
NASA Astrophysics Data System (ADS)
Zhang, Lei; Zheng, Wenbin; Song, Aiguo
2018-04-01
In the paper, the concept of logical stochastic resonance is applied to implement logic operation and latch operation in time-delayed synthetic genetic networks derived from a bacteriophage λ. Clear logic operation and latch operation can be obtained when the network is tuned by modulated periodic force and time-delay. In contrast with the previous synthetic genetic networks based on logical stochastic resonance, the proposed system has two advantages. On one hand, adding modulated periodic force to the background noise can increase the length of the optimal noise plateau of obtaining desired logic response and make the system adapt to varying noise intensity. On the other hand, tuning time-delay can extend the optimal noise plateau to larger range. The result provides possible help for designing new genetic regulatory networks paradigm based on logical stochastic resonance.
Programmable Differential Delay Circuit With Fine Delay Adjustment
DeRyckere, John F.; Jenkins, Philip Nord; Cornett, Frank Nolan
2002-07-09
Circuitry that provides additional delay to early arriving signals such that all data signals arrive at a receiving latch with same path delay. The delay of a forwarded clock reference is also controlled such that the capturing clock edge will be optimally positioned near quadrature (depending on latch setup/hold requirements). The circuitry continuously adapts to data and clock path delay changes and digital filtering of phase measurements reduce errors brought on by jittering data edges. The circuitry utilizes only the minimum amount of delay necessary to achieve objective thereby limiting any unintended jitter. Particularly, this programmable differential delay circuit with fine delay adjustment is designed to allow the skew between ASICS to be minimized. This includes skew between data bits, between data bits and clocks as well as minimizing the overall skew in a channel between ASICS.
Self-locking mechanical center joint
NASA Technical Reports Server (NTRS)
Bush, H. G.; Wallsom, R. E. (Inventor)
1985-01-01
A device for connecting, rotating and locking together a pair of structural half columns is described. The device is composed of an identical pair of cylindrical hub assemblies connected at their inner faces by a spring loaded hinge; each hub assembly having a structural half column attached to its outer end. Each hub assembly has a spring loading locking ring member movably attached adjacent to its inner face and includes a latch member for holding the locking ring in a rotated position subject to the force of its spring. Each hub assembly also has a hammer member for releasing the latch on the opposing hub assembly when the hub assemblies are rotated together. The spring loaded hinge connecting the hub assemblies rotates the hub assemblies and attached structural half columns together bringing the inner faces of the opposing hub assemblies into contact with one another.
NASA Astrophysics Data System (ADS)
German, Kristine A.; Kubby, Joel; Chen, Jingkuang; Diehl, James; Feinberg, Kathleen; Gulvin, Peter; Herko, Larry; Jia, Nancy; Lin, Pinyen; Liu, Xueyuan; Ma, Jun; Meyers, John; Nystrom, Peter; Wang, Yao Rong
2004-07-01
Xerox Corporation has developed a technology platform for on-chip integration of latching MEMS optical waveguide switches and Planar Light Circuit (PLC) components using a Silicon On Insulator (SOI) based process. To illustrate the current state of this new technology platform, working prototypes of a Reconfigurable Optical Add/Drop Multiplexer (ROADM) and a l-router will be presented along with details of the integrated latching MEMS optical switches. On-chip integration of optical switches and PLCs can greatly reduce the size, manufacturing cost and operating cost of multi-component optical equipment. It is anticipated that low-cost, low-overhead optical network products will accelerate the migration of functions and services from high-cost long-haul markets to price sensitive markets, including networks for metropolitan areas and fiber to the home. Compared to the more common silica-on-silicon PLC technology, the high index of refraction of silicon waveguides created in the SOI device layer enables miniaturization of optical components, thereby increasing yield and decreasing cost projections. The latching SOI MEMS switches feature moving waveguides, and are advantaged across multiple attributes relative to alternative switching technologies, such as thermal optical switches and polymer switches. The SOI process employed was jointly developed under the auspice of the NIST APT program in partnership with Coventor, Corning IntelliSense Corp., and MicroScan Systems to enable fabrication of a broad range of free space and guided wave MicroOptoElectroMechanical Systems (MOEMS).
Mechanical end joint system for connecting structural column elements
NASA Technical Reports Server (NTRS)
Bush, Harold G. (Inventor); Mikulas, Martin M., Jr. (Inventor); Wallsom, Richard E. (Inventor)
1990-01-01
A mechanical end joint system is presented that eliminates the possibility of free movements between the joint halves during loading or vibration. Both node joint body (NJB) and column end joint body (CEJB) have cylindrical engaging ends. Each of these ends has an integral semicircular tongue and groove. The two joint halves are engaged transversely - the tongue of the NJB mating with the groove of the CEJB and vice versa. The joint system employs a spring loaded internal latch mechanism housed in the CEJB. During mating, this mechanism is pushed away from the NJB and enters the NJB when mating is completed. In order to lock the joint and add a preload across the tongue and groove faces, an operating ring collar is rotated through 45 deg causing an internal mechanism to compress a Belleville washer preload mechanism. This causes an equal and opposite force to be exerted on the latch bolt and the latch plunger. This force presses the two joint halves tightly together. In order to prevent inadvertent disassembly, a secondary lock is also engaged when the joint is closed. Plungers are carried in the operating ring collar. When the joint is closed, the plungers fall into tracks on the CEJB, which allows the joint to be opened only when the operating ring collar and plungers are pushed directly away from the joining end. One application of this invention is the rapid assembly and disassembly of diverse skeletal framework structures which is extremely important in many projects involving the exploration of space.
Ninteenth Aerospace Mechanisms Symposium
NASA Technical Reports Server (NTRS)
1985-01-01
The proceedings of the 19th Aerospace Mechanisms Symposium are reported. Technological areas covered include space lubrication, bearings, aerodynamic devices, spacecraft/Shuttle latches, deployment, positioning, and pointing. Devices for spacecraft docking and manipulator and teleoperator mechanisms are also described.
... and cupboard safety latches. Post the national poison control number -- 1-800-222-1222 -- near the phone. DO NOT allow older infants to crawl or walk around in the kitchen while adults or older siblings are cooking. Block the kitchen ...
... your child's chance of injury in the home: Use safety latches and locks on cabinets and drawers. Buy all medicines with childproof caps and always keep them closed. Keep lightweight plastic bags, such as dry cleaning bags, grocery bags, and ...
SEU Performance of TAG Based Flip Flops
NASA Technical Reports Server (NTRS)
Shuler, Robert L.; Kouba, Coy; O'Neill, Patrick M.
2005-01-01
We describe heavy ion test results for two new SEU tolerant latches based on transition nand gates, one for single rail asynchronous and the other for dual rail synchronous designs, implemented in AMI 0.5microprocess.
49 CFR 236.341 - Latch shoes, rocker links, and quadrants.
Code of Federal Regulations, 2010 CFR
2010-10-01
..., INSPECTION, MAINTENANCE, AND REPAIR OF SIGNAL AND TRAIN CONTROL SYSTEMS, DEVICES, AND APPLIANCES Interlocking... downward force not exceeding a man's weight is exerted on the rocker while the lever is in the mid-stroke...
Tenth Aerospace Mechanisms Symposium
NASA Technical Reports Server (NTRS)
1976-01-01
Design studies and analyses were performed to describe the loads and dynamics of the space shuttle tail service masts. Of particular interest is the motion and interaction of the umbilical carrier plate, lanyard system, vacuum jacketed hoses, latches, links, and masthead.
18. Historic American Buildings Survey, N. E. Baldwin, Photographer December ...
18. Historic American Buildings Survey, N. E. Baldwin, Photographer December 1939, DINING ROOM LATCH, Gift of New York State Department of Education. - Shaker North Family, Dwelling House, Shaker Road, New Lebanon, Columbia County, NY
16. Historic American Buildings Survey, N. E. Baldwin, Photographer December ...
16. Historic American Buildings Survey, N. E. Baldwin, Photographer December 1939, EXTERIOR DOOR LATCH, Gift of New York State Department of Education. - Shaker North Family, Dwelling House, Shaker Road, New Lebanon, Columbia County, NY
19. Historic American Buildings Survey, N. E. Baldwin, Photographer December ...
19. Historic American Buildings Survey, N. E. Baldwin, Photographer December 1939, INTERIOR DOOR LATCH, Gift of New York State Department of Education. - Shaker North Family, Dwelling House, Shaker Road, New Lebanon, Columbia County, NY
49 CFR 571.113 - Standard No. 113; Hood latch system.
Code of Federal Regulations, 2013 CFR
2013-10-01
.... Application. This standard applies to passenger cars, multipurpose passenger vehicles, trucks, and buses. S3... engine, luggage, storage, or battery compartment. S4. Requirements. S4.1Each hood must be provided with a...
49 CFR 571.113 - Standard No. 113; Hood latch system.
Code of Federal Regulations, 2012 CFR
2012-10-01
.... Application. This standard applies to passenger cars, multipurpose passenger vehicles, trucks, and buses. S3... engine, luggage, storage, or battery compartment. S4. Requirements. S4.1Each hood must be provided with a...
49 CFR 571.113 - Standard No. 113; Hood latch system.
Code of Federal Regulations, 2011 CFR
2011-10-01
.... Application. This standard applies to passenger cars, multipurpose passenger vehicles, trucks, and buses. S3... engine, luggage, storage, or battery compartment. S4. Requirements. S4.1Each hood must be provided with a...
49 CFR 571.113 - Standard No. 113; Hood latch system.
Code of Federal Regulations, 2014 CFR
2014-10-01
.... Application. This standard applies to passenger cars, multipurpose passenger vehicles, trucks, and buses. S3... engine, luggage, storage, or battery compartment. S4. Requirements. S4.1Each hood must be provided with a...
49 CFR 571.113 - Standard No. 113; Hood latch system.
Code of Federal Regulations, 2010 CFR
2010-10-01
.... Application. This standard applies to passenger cars, multipurpose passenger vehicles, trucks, and buses. S3... engine, luggage, storage, or battery compartment. S4. Requirements. S4.1Each hood must be provided with a...
An Improved SEL Test of the ADV212 Video Codec
NASA Technical Reports Server (NTRS)
Wilcox, Edward P.; Campola, Michael J.; Nadendla, Seshagiri; Kadari, Madhusudhan; Gigliuto, Robert A.
2017-01-01
Single-event effect (SEE) test data is presented on the Analog Devices ADV212. Focus is given to the test setup used to improve data quality and validate single-event latch-up (SEL) protection circuitry.
87. April 1967 CHILD'S BED OF SILVERED WOOD CARVED IN ...
87. April 1967 CHILD'S BED OF SILVERED WOOD CARVED IN ANIMAL MOTIFS. NOTE DOORS WITH SQUIRREL LATCHES AND DECORATIVE SIMULATED HINGES - Mar-a-Lago, 1100 South Ocean Boulevard, Palm Beach, Palm Beach County, FL
Federal Register 2010, 2011, 2012, 2013, 2014
2013-06-03
... sales, CNH would be able to choose the duty rates during customs entry procedures that apply to...; ground straps; latches; plates; pumps; valves; fans; bushings; ballast assemblies; heaters; speakers...
Method and apparatus for eliminating unsuccessful tries in a search tree
NASA Technical Reports Server (NTRS)
Peterson, John C. (Inventor); Chow, Edward (Inventor); Madan, Herb S. (Inventor)
1991-01-01
A circuit switching system in an M-ary, n-cube connected network completes a best-first path from an originating node to a destination node by latching valid legs of the path as the path is being sought out. Each network node is provided with a routing hyperswitch sub-network, (HSN) connected between that node and bidirectional high capacity communication channels of the n-cube network. The sub-networks are all controlled by routing algorithms which respond to message identification headings (headers) on messages to be routed along one or more routing legs. The header includes information embedded therein which is interpreted by each sub-network to route and historically update the header. A logic circuit, available at every node, implements the algorithm and automatically forwards or back-tracks the header in the network legs of various paths until a completed path is latched.
An improved fast acquisition phase frequency detector for high speed phase-locked loops
NASA Astrophysics Data System (ADS)
Zhang, Lei; Wang, Zongmin; Zhang, Tieliang; Peng, Xinmang
2018-04-01
Phase-locked loops (PLL) have been widely applied in many high-speed designs, such as microprocessors or communication systems. In this paper, an improved fast acquisition phase frequency detector for high speed phase-locked loops is proposed. An improved structure based on dynamic latch is used to eliminate the non-ideal effect such as dead zone and blind zone. And frequency dividers are utilized to vastly extend the phase difference detection range and enhance the operation frequency of the PLL. Proposed PFD has been implemented in 65nm CMOS technology, which occupies an area of 0.0016mm2 and consumes 1.5mW only. Simulation results demonstrate that maximum operation frequency can be up to 5GHz. In addition, the acquisition time of PLL using proposed PFD is 1.0us which is 2.6 times faster than that of the PLL using latch-based PFD without divider.
NASA Astrophysics Data System (ADS)
Wang, Yongjun; Liu, Xinyu; Tian, Qinghua; Wang, Lina; Xin, Xiangjun
2018-03-01
Basic configurations of various all-optical clocked flip-flops (FFs) and optical random access memory (RAM) based on the nonlinear polarization rotation (NPR) effect of low-polarization-dependent semiconductor optical amplifiers (SOA) are proposed. As the constituent elements, all-optical logic gates and all-optical SR latches are constructed by taking advantage of the SOA's NPR switch. Different all-optical FFs (AOFFs), including SR-, D-, T-, and JK-types as well as an optical RAM cell were obtained by the combination of the proposed all-optical SR latches and logic gates. The effectiveness of the proposed schemes were verified by simulation results and demonstrated by a D-FF and 1-bit RAM cell experimental system. The proposed all-optical clocked FFs and RAM cell are significant to all-optical signal processing.
Digitally programmable signal generator and method
Priatko, G.J.; Kaskey, J.A.
1989-11-14
Disclosed is a digitally programmable waveform generator for generating completely arbitrary digital or analog waveforms from very low frequencies to frequencies in the gigasample per second range. A memory array with multiple parallel outputs is addressed; then the parallel output data is latched into buffer storage from which it is serially multiplexed out at a data rate many times faster than the access time of the memory array itself. While data is being multiplexed out serially, the memory array is accessed with the next required address and presents its data to the buffer storage before the serial multiplexing of the last group of data is completed, allowing this new data to then be latched into the buffer storage for smooth continuous serial data output. In a preferred implementation, a plurality of these serial data outputs are paralleled to form the input to a digital to analog converter, providing a programmable analog output. 6 figs.
Digitally programmable signal generator and method
Priatko, Gordon J.; Kaskey, Jeffrey A.
1989-01-01
A digitally programmable waveform generator for generating completely arbitrary digital or analog waveforms from very low frequencies to frequencies in the gigasample per second range. A memory array with multiple parallel outputs is addressed; then the parallel output data is latched into buffer storage from which it is serially multiplexed out at a data rate many times faster than the access time of the memory array itself. While data is being multiplexed out serially, the memory array is accessed with the next required address and presents its data to the buffer storage before the serial multiplexing of the last group of data is completed, allowing this new data to then be latched into the buffer storage for smooth continuous serial data output. In a preferred implementation, a plurality of these serial data outputs are paralleled to form the input to a digital to analog converter, providing a programmable analog output.
Transient fault behavior in a microprocessor: A case study
NASA Technical Reports Server (NTRS)
Duba, Patrick
1989-01-01
An experimental analysis is described which studies the susceptibility of a microprocessor based jet engine controller to upsets caused by current and voltage transients. A design automation environment which allows the run time injection of transients and the tracing from their impact device to the pin level is described. The resulting error data are categorized by the charge levels of the injected transients by location and by their potential to cause logic upsets, latched errors, and pin errors. The results show a 3 picoCouloumb threshold, below which the transients have little impact. An Arithmetic and Logic Unit transient is most likely to result in logic upsets and pin errors (i.e., impact the external environment). The transients in the countdown unit are potentially serious since they can result in latched errors, thus causing latent faults. Suggestions to protect the processor against these errors, by incorporating internal error detection and transient suppression techniques, are also made.
Optimization of the Switch Mechanism in a Circuit Breaker Using MBD Based Simulation
Jang, Jin-Seok; Yoon, Chang-Gyu; Ryu, Chi-Young; Kim, Hyun-Woo; Bae, Byung-Tae; Yoo, Wan-Suk
2015-01-01
A circuit breaker is widely used to protect electric power system from fault currents or system errors; in particular, the opening mechanism in a circuit breaker is important to protect current overflow in the electric system. In this paper, multibody dynamic model of a circuit breaker including switch mechanism was developed including the electromagnetic actuator system. Since the opening mechanism operates sequentially, optimization of the switch mechanism was carried out to improve the current breaking time. In the optimization process, design parameters were selected from length and shape of each latch, which changes pivot points of bearings to shorten the breaking time. To validate optimization results, computational results were compared to physical tests with a high speed camera. Opening time of the optimized mechanism was decreased by 2.3 ms, which was proved by experiments. Switch mechanism design process can be improved including contact-latch system by using this process. PMID:25918740
Optimized Latching Control of Floating Point Absorber Wave Energy Converter
NASA Astrophysics Data System (ADS)
Gadodia, Chaitanya; Shandilya, Shubham; Bansal, Hari Om
2018-03-01
There is an increasing demand for energy in today’s world. Currently main energy resources are fossil fuels, which will eventually drain out, also the emissions produced from them contribute to global warming. For a sustainable future, these fossil fuels should be replaced with renewable and green energy sources. Sea waves are a gigantic and undiscovered vitality asset. The potential for extricating energy from waves is extensive. To trap this energy, wave energy converters (WEC) are needed. There is a need for increasing the energy output and decreasing the cost requirement of these existing WECs. This paper presents a method which uses prediction as a part of the control scheme to increase the energy efficiency of the floating-point absorber WECs. Kalman Filter is used for estimation, coupled with latching control in regular as well as irregular sea waves. Modelling and Simulation results for the same are also included.
Iron-mediated soil carbon response to water-table decline in an alpine wetland
NASA Astrophysics Data System (ADS)
Wang, Yiyun; Wang, Hao; He, Jin-Sheng; Feng, Xiaojuan
2017-06-01
The tremendous reservoir of soil organic carbon (SOC) in wetlands is being threatened by water-table decline (WTD) globally. However, the SOC response to WTD remains highly uncertain. Here we examine the under-investigated role of iron (Fe) in mediating soil enzyme activity and lignin stabilization in a mesocosm WTD experiment in an alpine wetland. In contrast to the classic `enzyme latch' theory, phenol oxidative activity is mainly controlled by ferrous iron [Fe(II)] and declines with WTD, leading to an accumulation of dissolvable aromatics and a reduced activity of hydrolytic enzyme. Furthermore, using dithionite to remove Fe oxides, we observe a significant increase of Fe-protected lignin phenols in the air-exposed soils. Fe oxidation hence acts as an `iron gate' against the `enzyme latch' in regulating wetland SOC dynamics under oxygen exposure. This newly recognized mechanism may be key to predicting wetland soil carbon storage with intensified WTD in a changing climate.
Space Station Crew Walks in Space to Conduct Robotics Upgrades
2018-01-23
Outside the International Space Station, Expedition 54 Flight Engineers Mark Vande Hei and Scott Tingle of NASA conducted the first spacewalk this year Jan. 23 to replace a degraded latching end effector (LEE) on one end of the Canadarm2 robotic arm. There are two redundant end effectors on each end of the arm used to grapple visiting vehicles and components during a variety of operational activities. The spacewalk was the 206th in support of space station assembly and maintenance, the third in Vande Hei’s career and the first for Tingle. Vande Hei will venture outside the station again Jan. 29 with Flight Engineer Norishige Kanai of the Japan Aerospace Exploration Agency (JAXA) to stow a spare latching end effector removed from the robotic arm last October on to the station’s mobile base system rail car for future use.
Fukutomi, Toshiaki; Takagi, Kenji; Mizushima, Tsunehiro; Ohuchi, Noriaki
2014-01-01
Transcription factor Nrf2 (NF-E2-related factor 2) coordinately regulates cytoprotective gene expression, but under unstressed conditions, Nrf2 is degraded rapidly through Keap1 (Kelch-like ECH-associated protein 1)-mediated ubiquitination. Nrf2 harbors two Keap1-binding motifs, DLG and ETGE. Interactions between these two motifs and Keap1 constitute a key regulatory nexus for cellular Nrf2 activity through the formation of a two-site binding hinge-and-latch mechanism. In this study, we determined the minimum Keap1-binding sequence of the DLG motif, the low-affinity latch site, and defined a new DLGex motif that covers a sequence much longer than that previously defined. We have successfully clarified the crystal structure of the Keap1-DC-DLGex complex at 1.6 Å. DLGex possesses a complicated helix structure, which interprets well the human-cancer-derived loss-of-function mutations in DLGex. In thermodynamic analyses, Keap1-DLGex binding is characterized as enthalpy and entropy driven, while Keap1-ETGE binding is characterized as purely enthalpy driven. In kinetic analyses, Keap1-DLGex binding follows a fast-association and fast-dissociation model, while Keap1-ETGE binding contains a slow-reaction step that leads to a stable conformation. These results demonstrate that the mode of DLGex binding to Keap1 is distinct from that of ETGE structurally, thermodynamically, and kinetically and support our contention that the DLGex motif serves as a converter transmitting environmental stress to Nrf2 induction as the latch site. PMID:24366543
Breastfeeding Characteristics of Late-Preterm Infants in a Kangaroo Mother Care Unit.
Pike, Melissa; Kritzinger, Alta; Krüger, Esedra
2017-12-01
To describe the breastfeeding characteristics of late-preterm infants (LPIs) in a kangaroo mother care (KMC) unit. In a 20-bed KMC unit, the breastfeeding of 73 purposively-selected LPIs' (mean gestational age: 34.8 weeks) was observed once-off, using the Preterm Infant Breastfeeding Behavior Scale. Participants' mean age was 9.5 days, mean number of days in the unit was 3.1 days, and mean number of days breastfeeding was 7.5 on observation. Only 13.7% of participants were directly breastfeeding without supplementary naso- or orogastric feeding/cup-feeding and 86.3% received supplementary cup-feeding of expressed breast milk. Most participants did not exhibit obvious rooting (83.5%) and although most latched-on (97.3%), those who did, latched shallowly (93%). The mean longest sucking burst was 18.8 (standard deviation: 10.5) and approximately half the participants swallowed repeatedly (53.4%). The mean breastfeeding session duration was 17.8 minutes, but most participants breastfed for less than 10 minutes (76.7%). No statistically significant differences in breastfeeding characteristics were detected between participants of different chronological ages. A general trend toward more mature behaviors in participants' breastfeeding for more days was present for many breastfeeding characteristics. More infants exhibited the most mature behavior for each breastfeeding characteristic when the environment was quiet, rather than noisy and disturbing, except for depth of latching (quiet: 0%, disturbance: 15.2%). LPIs in this sample presented with subtle breastfeeding difficulties, highlighting their need for breastfeeding support. Further research is required to examine the effect of KMC on breastfeeding in LPIs.
Four-Point-Latching Microactuator
NASA Technical Reports Server (NTRS)
Toda, Risaku; Yang, Eui-Hyeok
2008-01-01
An experimental inchworm-type linear microactuator is depicted. This microactuator is a successor to one described in "MEMS-Based Piezoelectric/Electrostatic Inchworm Actuator" (NPO-30672), NASA Tech Briefs, Vol. 27, No. 6 (June 2003), page 68. Both actuators are based on the principle of using a piezoelectric transducer operated in alternation with electrostatically actuated clutches to cause a slider to move in small increments. However, the design of the present actuator incorporates several improvements over that of the previous one. The most readily apparent improvement is in geometry and, consequently, in fabrication: In the previous actuator, the inchworm motion was perpendicular to the broad faces of a flat silicon wafer on which the actuator was fabricated, and fabrication involved complex processes to form complex three-dimensional shapes in and on the wafer. In the present actuator, the inchworm motion is parallel to the broad faces of a wafer on which it is fabricated. The components needed to produce the in-plane motion are nearly planar in character and, consequently, easier to fabricate. Other advantages of the present design are described, including that the previous actuator contained two clutches (denoted 'holders' in the cited prior article), the present actuator contains four clutches. The operational sequence of the previous two-clutch actuator is similar. However, the two-clutch configuration is susceptible to tilt of the slider and a consequent large increase in drag. Hence, the primary operational advantages of the present four-point-latching design over the prior two-point-latching design are less drag and greater control robustness arising from greater stability of the orientation of the slider.
A robot end effector exchange mechanism for space applications
NASA Technical Reports Server (NTRS)
Gorin, Barney F.
1990-01-01
Efficient robot operation requires the use of specialized end effectors or tools for tasks. In spacecraft applications, the microgravity environment precludes the use of gravitational forces to retain the tools in holding fixture. As a result of this, a retention mechanism which forms a part of the tool storage container is required. A unique approach to this problem has resulted in the development of an end effector exchange mechanism that meets the requirements for spaceflight applications while avoiding the complexity usually involved. This mechanism uses multiple latching cams both on the manipulator and in the tool storage container, combined with a system of catch rings to provide retention in both locations and the required failure tolerance. Because of the cam configuration the mechanism operates passively, requiring no electrical commands except those needed to move the manipulator into position. Similarly, it inherently provides interlocks to prevent the release of one cam before its opposite number is engaged.
Development of the Aquarius Antenna Deployment Mechanisms and Spring/Damper Actuator
NASA Technical Reports Server (NTRS)
Johnson, Joel A.
2008-01-01
The Aquarius Instrument s large radar reflector dish needed to be stowed for launch, and then deployed on-orbit. The Deployment Subsystem consisted of a cantilevered boom structure and two single-axis hinge mechanisms to accurately deploy and position the reflector dish relative to the radar feed horns. The cantilevered design demanded high stiffness and accuracy from the deployment mechanism at the root of the boom. A preload-generating end-of-travel latch was also required. To largely eliminate the need for control systems, each deployment mechanism was actuated by a passive spring motor with viscous-fluid damping. Tough requirements and adaptation of a heritage actuator to the new application resulted in numerous challenges. Fabrication, assembly, and testing encountered additional problems, though ultimately the system was demonstrated very successfully. This paper revisits the development to highlight which design concepts worked and the many important lessons learned.
The 17th Aerospace Mechanisms Symposium
NASA Technical Reports Server (NTRS)
1983-01-01
The proceedings of the Aerospace Mechanisms Symposium are reported. Technological areas covered include space lubrication, aerodynamic devices, spacecraft/Shuttle latches, deployment, positioning, and pointing. Devices for spacecraft tether, magnetic bearing suspension, explosive welding, and a deployable/retractable mast are also described.
17. Historic American Buildings Survey, N. E. Baldwin, Photographer December ...
17. Historic American Buildings Survey, N. E. Baldwin, Photographer December 1939, FRONT DOOR LATCH AND BOLT, Gift of New York State Department of Education. - Shaker North Family, Dwelling House, Shaker Road, New Lebanon, Columbia County, NY
Code of Federal Regulations, 2010 CFR
2010-01-01
... NON-FULL-SIZE BABY CRIBS § 1509.7 Hardware. (a) The hardware in a non-full-size baby crib shall be... abuse. (b) Non-full-size baby cribs shall incorporate locking or latching devices for dropsides or... non-full-size baby crib. ...
Child restraint use survey : LATCH use and misuse
DOT National Transportation Integrated Search
2006-12-01
NHTSA conducted a survey from April to October 2005 to collect information about the types of restraint systems that were being used to keep children safe while riding in passenger vehicles. In particular, NHTSA was interested in whether drivers with...
Evaluation of Recent Technologies of Nonvolatile RAM
NASA Astrophysics Data System (ADS)
Nuns, Thierry; Duzellier, Sophie; Bertrand, Jean; Hubert, Guillaume; Pouget, Vincent; Darracq, FrÉdÉric; David, Jean-Pierre; Soonckindt, Sabine
2008-08-01
Two types of recent nonvolatile random access memories (NVRAM) were evaluated for radiation effects: total dose and single event upset and latch-up under heavy ions and protons. Complementary irradiation with a laser beam provides information on sensitive areas of the devices.
Self-Alining, Latching Joint For Folding Structural Elements
NASA Technical Reports Server (NTRS)
Bush, H. G.; Wallsom, R. E.
1982-01-01
Structural column elements assembled quickly and easily with aid of new center joint. Joint alines column elements automatically and fastens them together securely. Tapered half columns are stacked like paper cups, unfolded, and connected to other similar elements to form truss structures.
NASA Technical Reports Server (NTRS)
Calco, Frank S. (Inventor)
1991-01-01
A quick release toggle clamp that utilizes a spring that requires a deliberate positive action for disengagement is presented. The clamp has a sliding bolt that provides a latching mechanism. The bolt is moved by a handle that tends to remain in an engaged position while under tension.
49 CFR 571.224 - Standard No. 224; Rear impact protection.
Code of Federal Regulations, 2010 CFR
2010-10-01
... trailers, pulpwood trailers, road construction controlled horizontal discharge trailers, special purpose... latches are excluded from the determination of the rearmost point. Road construction controlled horizontal... machine or paving equipment for road construction and paving operations. Rounded corner means a guard's...
Demirci, Jill R.; Bogen, Debra L.
2017-01-01
Background Primiparous women are at-risk for early, unintended breastfeeding reduction and cessation. Breastfeeding patterns that contribute to these outcomes require further exploration. Research Aim/Questions To describe early, “real time” breastfeeding behaviors and perceived problems of primiparous women. Methods First-time mothers intending to exclusively breastfeed downloaded a commercial infant feeding app during their postpartum hospitalization. Women logged feedings and their breastfeeding experiences, as they occurred, through eight weeks postpartum. Additional feeding and background data were collected via EMR and questionnaires administered at enrollment, two, and eight weeks postpartum. Summary statistics were compiled to examine weekly breastfeeding behaviors and problems. Results In this sample of 61 primarily highly-educated, White women committed to breastfeeding, 38% (n=23) used formula during the postpartum hospitalization and 68% (n=34) used formula at least once by two weeks. Nine women stopped breastfeeding during the study. Women using any formula in the hospital and those with less positive baseline attitudes toward breastfeeding were less likely to be exclusively breastfeeding at two and eight weeks, respectively (p<0.05). There was a trend toward declining at-breast feeds and high rates of milk expression during the study. Breastfeeding problems peaked at Week 2, with 81% of women (n=39) endorsing at least one problem at that time. The most prevalent problems included perception of inadequate milk, pain, latching, and inefficient feeds. Conclusions Interventions to address suboptimal breastfeeding in primiparous women should consider the pervasiveness of early milk expression and in-hospital formula supplementation in this population, as well as the trajectory of common problems. PMID:28418803
2013-01-01
Background Mothers’ poor knowledge and negative attitude towards breastfeeding may influence practices and constitute barriers to optimizing the benefits of the baby-friendly initiative. This study assessed breastfeeding knowledge, attitude and techniques of postures, positioning, hold practice and latch-on among Nigerian mothers from a Semi-Urban community. Methods Three hundred and eighty three consenting lactating mothers who have breastfed for 6 months and up to two years volunteered for this cross-sectional survey, yielding a response rate of 95.7%. A self-administered questionnaire that sought information on maternal socio-demographic variables, knowledge, attitudes and breastfeeding techniques of mothers was employed. Results Based on cumulative breastfeeding knowledge and attitude scores, 71.3% of the respondents had good knowledge while 54.0% had positive attitude. Seventy one point three percent practiced advisable breastfeeding posture. Sitting on a chair to breastfeed was common (62.4%); and comfort of mother/baby (60.8%) and convenience (29.5%) were the main reasons for adopting breastfeeding positions. Cross-cradle hold (80.4%), football hold technique (13.3%), breast-to-baby (18.0%) and baby-to-breast latch-on (41.3%) were the common breastfeeding techniques. A majority of the respondents (75.7%) agreed that neck flexion, slight back flexion, arm support with pillow and foot rest was essential during breastfeeding. There was no significant association between breastfeeding posture practice and each of cumulative breastfeeding knowledge score levels (X2 = 0.044; p = 0.834) and attitude score levels (X2 = 0.700; p = 0.403). Conclusion Nigerian mothers demonstrated good knowledge and positive attitude towards breastfeeding. Most of the mothers practiced advisable breastfeeding postures, preferred sitting on a chair to breastfeed and utilized cross-cradle hold and baby-to-breast latch-on. PMID:24359943
14 CFR 25.783 - Fuselage doors.
Code of Federal Regulations, 2014 CFR
2014-01-01
... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Fuselage doors. 25.783 Section 25.783 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS... not latch after closing; and (ii) With jamming as a result of mechanical failure or blocking debris...
14 CFR 25.783 - Fuselage doors.
Code of Federal Regulations, 2011 CFR
2011-01-01
... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Fuselage doors. 25.783 Section 25.783 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS... not latch after closing; and (ii) With jamming as a result of mechanical failure or blocking debris...
14 CFR 25.783 - Fuselage doors.
Code of Federal Regulations, 2012 CFR
2012-01-01
... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Fuselage doors. 25.783 Section 25.783 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS... not latch after closing; and (ii) With jamming as a result of mechanical failure or blocking debris...
47. MISSISSIPPI, LOWNDES CO. COLUMBUS RAILROAD BRIDGE End of 1st ...
47. MISSISSIPPI, LOWNDES CO. COLUMBUS RAILROAD BRIDGE End of 1st St. S., Columbus, Ms. Latching mechanism, E end of turn span, viewed from W. Sarcone Photography, Columbus, Ms. Sep 1978. - Bridges of the Upper Tombigbee River Valley, Columbus, Lowndes County, MS
48. MISSISSIPPI, LOWNDES CO. COLUMBUS RAILROAD BRIDGE End of 1st ...
48. MISSISSIPPI, LOWNDES CO. COLUMBUS RAILROAD BRIDGE End of 1st St. S., Columbus, Ms Latching mechanism, E end of turn span, view from N. Sarcone Photography, Columbus, MS. Sep 1978. - Bridges of the Upper Tombigbee River Valley, Columbus, Lowndes County, MS
14 CFR 25.783 - Fuselage doors.
Code of Federal Regulations, 2013 CFR
2013-01-01
... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Fuselage doors. 25.783 Section 25.783 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS... not latch after closing; and (ii) With jamming as a result of mechanical failure or blocking debris...
14 CFR 25.783 - Fuselage doors.
Code of Federal Regulations, 2010 CFR
2010-01-01
... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Fuselage doors. 25.783 Section 25.783 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS... not latch after closing; and (ii) With jamming as a result of mechanical failure or blocking debris...
DOE Office of Scientific and Technical Information (OSTI.GOV)
Marshall, J.R.; Hardin, R.T. Jr.
1987-07-07
This patent describes a nuclear reactor installation including means defining a fuel handling area and means defining a containment area separated from the fuel handling area and including a refuelling cavity; the improvement comprising: (a) a fuel transfer tube connecting the refuelling cavity with the fuel handling area; the fuel transfer tube having a first end in the fuel handling area and a second end in the refueling cavity; (b) valve means for opening and closing the first end; and (c) a hatch assembly mounted on the second end; the hatch assembly including (1) a hatch ring affixed to themore » fuel transfer tube at the second end the hatch ring has an integral annular seat surrounded by the hatch ring and defines a hatch opening in the second end of the fuel transfer tube; (2) a hatch cover adapts to be positioned on the annular seat for covering the hatch opening; (3) latching units are supported on the hatch ring about the hatch opening, each latching unit.« less
Lerner, Itamar; Bentin, Shlomo; Shriki, Oren
2012-01-01
Localist models of spreading activation (SA) and models assuming distributed-representations offer very different takes on semantic priming, a widely investigated paradigm in word recognition and semantic memory research. In the present study we implemented SA in an attractor neural network model with distributed representations and created a unified framework for the two approaches. Our models assumes a synaptic depression mechanism leading to autonomous transitions between encoded memory patterns (latching dynamics), which account for the major characteristics of automatic semantic priming in humans. Using computer simulations we demonstrated how findings that challenged attractor-based networks in the past, such as mediated and asymmetric priming, are a natural consequence of our present model’s dynamics. Puzzling results regarding backward priming were also given a straightforward explanation. In addition, the current model addresses some of the differences between semantic and associative relatedness and explains how these differences interact with stimulus onset asynchrony in priming experiments. PMID:23094718
Lerner, Itamar; Bentin, Shlomo; Shriki, Oren
2014-01-01
Semantic priming has long been recognized to reflect, along with automatic semantic mechanisms, the contribution of controlled strategies. However, previous theories of controlled priming were mostly qualitative, lacking common grounds with modern mathematical models of automatic priming based on neural networks. Recently, we have introduced a novel attractor network model of automatic semantic priming with latching dynamics. Here, we extend this work to show how the same model can also account for important findings regarding controlled processes. Assuming the rate of semantic transitions in the network can be adapted using simple reinforcement learning, we show how basic findings attributed to controlled processes in priming can be achieved, including their dependency on stimulus onset asynchrony and relatedness proportion and their unique effect on associative, category-exemplar, mediated and backward prime-target relations. We discuss how our mechanism relates to the classic expectancy theory and how it can be further extended in future developments of the model. PMID:24890261
On the Emergence of Modern Humans
ERIC Educational Resources Information Center
Amati, Daniele; Shallice, Tim
2007-01-01
The emergence of modern humans with their extraordinary cognitive capacities is ascribed to a novel type of cognitive computational process (sustained non-routine multi-level operations) required for abstract projectuality, held to be the common denominator of the cognitive capacities specific to modern humans. A brain operation (latching) that…
Downhower, Jr., Francis H.; Finlayson, Paul T.
1984-04-10
A snubber circuit coupled across each thyristor to be gated in a chain of thyristors determines the critical output of a NOR LATCH whenever one snubber circuit could not be charged and discharged under normal gating conditions because of a short failure.
29 CFR 1926.753 - Hoisting and rigging.
Code of Federal Regulations, 2011 CFR
2011-07-01
... (CONTINUED) SAFETY AND HEALTH REGULATIONS FOR CONSTRUCTION Steel Erection § 1926.753 Hoisting and rigging. (a... used in steel erection activities shall be visually inspected prior to each shift by a competent person... and latches for deformation, chemical damage, cracks, or wear; (F) Wire rope reeving for compliance...
16 CFR 1750.5 - Detailed requirements.
Code of Federal Regulations, 2010 CFR
2010-01-01
... 16 Commercial Practices 2 2010-01-01 2010-01-01 false Detailed requirements. 1750.5 Section 1750.5 Commercial Practices CONSUMER PRODUCT SAFETY COMMISSION REFRIGERATOR SAFETY ACT REGULATIONS STANDARD FOR... directed perpendicularly to the plane of the door and applied anywhere along the latch edge of the inside...
The 26th Aerospace Mechanisms Symposium
NASA Technical Reports Server (NTRS)
1992-01-01
The proceedings of the 26th Aerospace Mechanisms Symposium, which was held at the Goddard Space Flight Center on May 13, 14, and 15, 1992 are reported. Technological areas covered include actuators, aerospace mechanism applications for ground support equipment, lubricants, latches, connectors and other mechanisms for large space structures.
ERIC Educational Resources Information Center
Wiedeman, Reeves
2008-01-01
Supporters of affirmative action may have finally found a way to defeat state ballot measures that would ban such programs: Latch onto an inspirational presidential candidate with piles of cash and an unprecedented voter-turnout machine. Those activists won a narrow victory in Colorado this month, when 50.7 percent of voters made the state the…
77 FR 3579 - Airworthiness Directives; The Boeing Company Airplanes
Federal Register 2010, 2011, 2012, 2013, 2014
2012-01-25
..., relocating and adjusting the sensor target and the sensor proximity switch, and testing to ensure positive... bearings and lockbase retainer in the door latch assembly, relocating and adjusting the sensor target and the sensor proximity switch, and testing to ensure positive door locking and corrective action if...
77 FR 52220 - Safety Standard for Play Yards
Federal Register 2010, 2011, 2012, 2013, 2014
2012-08-29
... product, including mobiles, toy bars, canopies, bassinets, and changing tables. C. Incident Data The... between different comments. The number assigned to each comment is purely for organizational purposes and... most play yards form a dangerous V-shape if the side rail latch mechanisms are not locked properly. The...
Magnetic bearings for a high-performance optical disk buffer, volume 2
NASA Technical Reports Server (NTRS)
1990-01-01
The operating instructions for the magnetic bearings of a high-performance optical disk buffer are provided. Among the topics that are discussed are the following: front panel layout, turn-on procedure, shut-down procedure, and latch-up protection. Additionally, comprehensive engineering drawings are presented for the design.
The 22nd Aerospace Mechanisms Symposium
NASA Technical Reports Server (NTRS)
1988-01-01
The proceedings of the symposium, which was held at the NASA Langley Research Center, on May 4 to 6, 1988, are reported. Technological areas covered include space lubrication, bearings, aerodynamic devices, spacecraft latches, deployment, positioning, and pointing. Devices for space station docking and manipulator and teleoperator mechanisms are also described.
ERIC Educational Resources Information Center
Styer, Dan
2015-01-01
My favorite exam question comes from the final exam in an introductory mechanics course: "A rolling 31 ton railroad boxcar collides with a stationary flatcar. The coupling mechanism activates so the cars latch together and roll down the track attached. Of the initial kinetic energy, 38% dissipates as heat, sound, vibrations, mechanical…
The 27th Aerospace Mechanisms Symposium
NASA Technical Reports Server (NTRS)
Mancini, Ron (Compiler)
1993-01-01
The proceedings of the 27th Aerospace Mechanisms Symposium, which was held at ARC, Moffett Field, California, on 12-14 May 1993, are reported. Technological areas covered include the following: actuators, aerospace mechanism applications for ground support equipment, lubricants, latches, connectors, robotic mechanisms, and other mechanisms for large space structures.
Reconceiving ISD: Three Perspectives on Rapid Prototyping as a Paradigm Shift.
ERIC Educational Resources Information Center
Rathbun, Gail A.; And Others
Confronting recent design challenges, instructional designers have latched onto adaptive procedural techniques from outside the Instructional Systems Design (ISD) field. This discussion of rapid prototyping (RP) examines the perspectives of: (1) the prototype as the designer"s cognitive tool; (2) the designer as co-inquirer; and (3) the…
75 FR 37343 - Federal Motor Vehicle Safety Standards; Occupant Crash Protection
Federal Register 2010, 2011, 2012, 2013, 2014
2010-06-29
...\\ Morgan, Christina. ``Effectiveness of Lap/Shoulder Belts in the Back Outboard Seating Positions,'' DOT HS... has also pursued vehicle-based technologies for increasing seat belt use. These include sensors in the... driver position, enhanced SBRSs primarily relied on sensors found in the seat belt buckle and latch...
77 FR 6522 - Airworthiness Directives; The Boeing Company Airplanes
Federal Register 2010, 2011, 2012, 2013, 2014
2012-02-08
...Rulemaking Portal: Go to http://www.regulations.gov . Follow the instructions for submitting comments. Fax... hold the door closed for the design loads. Fractured and missing latch pin retention bolts, if not... cargo door, fuselage frames, internal and external skin of the fuselage, cargo door frames, mid-span...
49 CFR 571.224 - Standard No. 224; Rear impact protection.
Code of Federal Regulations, 2011 CFR
2011-10-01
... the vehicle is in motion. Nonstructural protrusions such as taillights, rubber bumpers, hinges and... deliver asphalt and other road building materials, in a controlled horizontal manner, into a lay down... protrusions such as taillights, hinges, rubber bumpers, and latches are excluded from the determination of the...
Code of Federal Regulations, 2010 CFR
2010-10-01
... 49 Transportation 4 2010-10-01 2010-10-01 false Fire doors. 230.82 Section 230.82 Transportation... Signals, Sanders and Lights § 230.82 Fire doors. (a) General provisions. Each steam locomotive shall have a fire door which shall latch securely when closed and which shall be maintained in a safe and...
Engineering the Ideal Array (BRIEFING CHARTS)
2007-03-05
48 V, f = 10 GHz GaN HEMT Transistor i t Dramatically higher: • Output power • Efficiency • Bandwidth GaN HEMT Power Amplifier lifi ...functions – RF amplifiers – 4-bit phase shifters – Amplitude controllers – Summing network – Power control – Latches for phase state – Address
SEABEE Pretest Results of the Joint Logistics-over-the-Shore (LOTS) Test and Evaluation Program.
1977-12-07
in the harbor. None of the equipment required extensive shoring. Some chocks and * wedges were placed on the equipment to increase its stability. P...incident. A subsequent examination revealed considerable structural damage to *the Peck & Hale tie-downs. Evidently one of the latching devices
2008-06-01
didn’t stop, the grappling hooks were re- motely engaged to latch onto the vehicle while the airbags deployed to lift the vehicle off the ground...successfully stopping it. The other device was a simple wooden wedge . If you didn’t stop, your vehicle would run up onto the in- cline of the wedge and
Political Integration of Hezbollah into Lebanese Politics
2009-06-01
by driving a wedge between the increasingly resented PLO fedayeen and the locally victimized Shi’a. The dynamic of dispossession, political for the...Movement Theory,” 10-11. 66 Ibid., 16. 32 Building upon the success of the Iranian revolution, the early founders of Hezbollah sought to latch onto
Auto-Zero Differential Amplifier
NASA Technical Reports Server (NTRS)
Quilligan, Gerard T. (Inventor); Aslam, Shahid (Inventor)
2017-01-01
An autozero amplifier may include a window comparator network to monitor an output offset of a differential amplifier. The autozero amplifier may also include an integrator to receive a signal from a latched window comparator network, and send an adjustment signal back to the differential amplifier to reduce an offset of the differential amplifier.
SFU rendezvous and SAP jettison
1996-01-13
STS072-720-076 (13 Jan. 1996) --- The crewmembers captured this 35mm view of the Japanese Space Flyer Unit (SFU) following the jettisoning of the solar panels. Later they used the Remote Manipulator System (RMS) to latch onto the satellite and berth it in the Space Shuttle Endeavour's aft cargo bay.
Design and analysis of a novel latch system implementing fiber-reinforced composite materials
NASA Astrophysics Data System (ADS)
Guevara Arreola, Francisco Javier
The use of fiber-reinforced composite materials have increased in the last four decades in high technology applications due to their exceptional mechanical properties and low weight. In the automotive industry carbon fiber have become popular exclusively in luxury cars because of its high cost. However, Carbon-glass hybrid composites offer an effective alternative to designers to implement fiber-reinforced composites into several conventional applications without a considerable price increase maintaining most of their mechanical properties. A door latch system is a complex mechanism that is under high loading conditions during car accidents such as side impacts and rollovers. Therefore, the Department of Transportation in The United States developed a series of tests that every door latch system comply in order to be installed in a vehicle. The implementation of fiber-reinforced composite materials in a door latch system was studied by analyzing the material behavior during the FMVSS No. 206 transverse test using computational efforts and experimental testing. Firstly, a computational model of the current forkbolt and detent structure was developed. Several efforts were conducted in order to create an effective and time efficient model. Two simplified models were implemented with two different contact interaction approaches. 9 composite materials were studied in forkbolt and 5 in detent including woven carbon fiber, unidirectional carbon fiber, woven carbon-glass fiber hybrid composites and unidirectional carbon-glass fiber hybrid composites. The computational model results showed that woven fiber-reinforced composite materials were stiffer than the unidirectional fiber-reinforced composite materials. For instance, a forkbolt made of woven carbon fibers was 20% stiffer than a forkbolt made of unidirectional fibers symmetrically stacked in 0° and 90° alternating directions. Furthermore, Hybrid composite materials behaved as expected in forkbolt noticing a decline in the load-displacement slopes while the percentage of glass fiber increased. In the other hand, results showed that a detent made of only glass fiber layers was preferable than a carbon-glass fiber hybrid detent due to the high stresses shown in carbon fiber layers. Ultimately, forkbolt and detent were redesigned according to their functionality and test results. It was observed that the new design was stiffer than the original by showing a steeper load-displacement curve. Subsequently, an experimental procedure was performed in order to correlate computational model results. Fiber-reinforced composite forkbolt and detent were waterjet cut from a composite laminate manufactured by Vacuum Assisted Resin Transfer Molding (VART) process. Then, samples were tested according to the computational model. Six testing sample combinations of forkbolt and detent were tested including the top three woven iterations forkbolts from the computational model paired with woven and unidirectional glass fiber detents. Test results showed a stiffness drop of 15% when the carbon fiber percentage decreases from 100% to 75%. Also, it was observed that woven glass fiber detent was superior to the unidirectional glass fiber detent by presenting a forkbolt-detent stiffness 38% higher. Moreover, the new design of forkbolt and detent were tested showing a stiffness increment of 29%. Furthermore, it was observed that fiber-reinforced composite forkbolt and detent did not reach the desired load of 5000 N. However, the redesigned forkbolt made of 100% woven carbon fiber and the redesign detent made of 100% woven glass fiber were close to reach that load. The design review based on test results performed (DRBTR) showed that components did not fail where the computational model concluded to be the areas with the highest maximum principal stress. In contrast to the computational model, all samples failed at the contact area between forkbolt and detent.
Crashworthy Troop Seat Testing Program
1977-11-01
19 ’rest 4 . . . . . . . . . .. . 29 | Detail Design’Finalization. .... 29 Vertical Wire - Bending Energy Attenuator 32 Toggle Latch...Strut Wire - Bending Attenuator Force Deflection. . . . ................... 28 15 Notched Wire and Pin Anchorage Test Specimen . 30 16 Quick-Disconnect...and Hold-Down Cable ......... 31 17 Failed Hold-Down Cable ...... . . . . 31 18 Wire - Bending Tension/Compression Energy Attenuator
49 CFR 571.209 - Standard No. 209; Seat belt assemblies.
Code of Federal Regulations, 2010 CFR
2010-10-01
.... (1) Eye bolts, shoulder bolts, or other bolt used to secure the pelvic restraint of seat belt... connecting webbing to an eye bolt shall be provided with a retaining latch or keeper which shall not move...) Single attachment hook for connecting webbing to any eye bolt shall be tested in the following manner...
Test results for SEU and SEL immune memory circuits
NASA Technical Reports Server (NTRS)
Wiseman, D.; Canaris, J.; Whitaker, S.; Gambles, J.; Arave, K.; Arave, L.
1993-01-01
Test results for three SEU logic/circuit hardened CMOS memory circuits verify upset and latch-up immunity for two configurations to be in excess of 120 MeV cm(exp 2)/mg using a commercial, non-radiation hardened CMOS process. Test chips from three separate fabrication runs in two different process were evaluated.
Educators Assess "Open Content" Movement
ERIC Educational Resources Information Center
Trotter, Andrew
2009-01-01
This article discusses the open-content movement in education. A small but growing movement of K-12 educators is latching on to educational resources that are "open," or free for others to use, change, and republish on web sites that promote sharing. The open-content movement is fueled partly by digital creation tools that make it easy…
77 FR 55768 - Airworthiness Directives; The Boeing Company Airplanes
Federal Register 2010, 2011, 2012, 2013, 2014
2012-09-11
... prompted by a report that during a test of the oxygen system, an operator found that the passenger oxygen masks did not properly flow oxygen, and that a loud noise occurred in the overhead area, which was... airplane oxygen system to ensure clamshell couplers are installed and fully latched, and corrective actions...
Federal Register 2010, 2011, 2012, 2013, 2014
2012-08-06
... Transmission Braking Effect, 103 Windshield Defrosting and Defogging Systems, 104 Windshield Wiping and Washing..., 113 Hood Latch System, 114 Theft Protection, 116 Motor Vehicle Brake Fluids, Standard No. 118 Power-Operated Window, Partition, and Roof Panel Systems, 119 New Pneumatic Tires for Vehicles other than...
75 FR 32863 - Airworthiness Directives; PILATUS AIRCRAFT LTD. Model PC-12/47E Airplanes
Federal Register 2010, 2011, 2012, 2013, 2014
2010-06-10
... describes the unsafe condition as: Reports have been received indicating that, if the power control friction...: Reports have been received indicating that, if the power control friction wheel is tightened, the reverse... indicating that, if the power control friction wheel is tightened, the reverse thrust latch may stick and...
NASA Technical Reports Server (NTRS)
Fox, D. A.
1977-01-01
Solid-state relay (SSR), containing multinode control logic, is operated as normally open, normally closed, or latched. Moreover several can be paralleled to form two-pole or double-throw relays. Versatile unit ends need to design custom control circuit for every relay application. Technique can be extended to incorporate selectable time delay, on operation or release, or pulsed output.
ERIC Educational Resources Information Center
Lerner, Itamar; Bentin, Shlomo; Shriki, Oren
2012-01-01
Localist models of spreading activation (SA) and models assuming distributed representations offer very different takes on semantic priming, a widely investigated paradigm in word recognition and semantic memory research. In this study, we implemented SA in an attractor neural network model with distributed representations and created a unified…
ERIC Educational Resources Information Center
Chiariello, Michael S.
2007-01-01
Carved from cedar trees by the Native people of the Northwest Coast, totems are outgrowths of the region's aboriginal art forms. Originally an important part of the pot-latch ceremony--a feast with deep meaning to coastal First Nations--totem poles were once raised to represent a family clan, its kinship system, dignity, accomplishments, prestige,…
The 21st Aerospace Mechanisms Symposium
NASA Technical Reports Server (NTRS)
1987-01-01
During the symposium technical topics addressed included deployable structures, electromagnetic devices, tribology, actuators, latching devices, positioning mechanisms, robotic manipulators, and automated mechanisms synthesis. A summary of the 20th Aerospace Mechanisms Symposium panel discussions is included as an appendix. However, panel discussions on robotics for space and large space structures which were held are not presented herein.
NASA Technical Reports Server (NTRS)
Ardalan, Sasan (Inventor)
2018-01-01
The invention relates to devices and methods of maintaining the current starved delay at a constant value across variations in voltage and temperature to increase the speed of operation of the sequential logic in the radiation hardened ASIC design.
Japanese Space Flyer Unit (SFU) satellite rendezvous
1996-01-20
STS072-720-042 (13 Jan. 1996) --- The crew members captured this 70mm view of the Japanese Space Flyer Unit (SFU) just prior to the jettisoning of the solar panels. Later, they used the Remote Manipulator System (RMS) to latch onto the satellite and berth it in the Space Shuttle Endeavour’s aft cargo bay.
Ni, Xin-long; Zeng, Xi; Redshaw, Carl; Yamato, Takehiko
2011-07-15
A ratiometric fluorescent receptor with a C(3) symmetric structure based on a pyrene-linked triazole-modified homooxacalix[3]arene (L) was synthesized and characterized. This system exhibited an interesting ratiometric detection signal output for targeting cations and anions through switching the excimer emission of pyrene from the "on-off" to the "off-on" type in neutral solution. (1)H NMR titration results suggested that the Zn(2+) center of receptor L·Zn(2+) provided an excellent pathway of organizing anion binding groups for optimal host-guest interactions. It is thus believed that this receptor has potential application in sensing, detection, and recognition of both Zn(2+) and H(2)PO(4)(-) ions with different optical signals. In addition, the fluorescence emission changes by the inputs of Zn(2+) and H(2)PO(4)(-) ions can be viewed as a combinational R-S latch logic circuit at the molecular level.
CMOS based capacitance to digital converter circuit for MEMS sensor
NASA Astrophysics Data System (ADS)
Rotake, D. R.; Darji, A. D.
2018-02-01
Most of the MEMS cantilever based system required costly instruments for characterization, processing and also has large experimental setups which led to non-portable device. So there is a need of low cost, highly sensitive, high speed and portable digital system. The proposed Capacitance to Digital Converter (CDC) interfacing circuit converts capacitance to digital domain which can be easily processed. Recent demand microcantilever deflection is part per trillion ranges which change the capacitance in 1-10 femto farad (fF) range. The entire CDC circuit is designed using CMOS 250nm technology. Design of CDC circuit consists of a D-latch and two oscillators, namely Sensor controlled oscillator (SCO) and digitally controlled oscillator (DCO). The D-latch is designed using transmission gate based MUX for power optimization. A CDC design of 7-stage, 9-stage and 11-stage tested for 1-18 fF and simulated using mentor graphics Eldo tool with parasitic. Since the proposed design does not use resistance component, the total power dissipation is reduced to 2.3621 mW for CDC designed using 9-stage SCO and DCO.
K-band high power latching switch. [communication satellite system
NASA Technical Reports Server (NTRS)
Mlinar, M. J.; Piotrowski, W. S.; Raue, J. E.
1980-01-01
A 19 GHz waveguide latching switch with a bandwidth of 1400 MHz and an exceptionally low insertion loss of 0.25 dB was demonstrated. The RF and driver ferrites are separate structures and can be optimized individually. This analysis for each structure is separately detailed. Basically, the RF section features a dual turnstile junction. The circulator consists of a dielectric tube which contains two ferrite rods, and a dielectric spacer separating the ferrite parts along the center of symmetry of the waveguide to form two turnstiles. This subassembly is indexed and locked in the center of symmetry of a uniform junction of three waveguides by the metallic transformers installed in the top and bottom walls of the housing. The switching junction and its actuating circuitry met all RF performance objectives and all shock and vibration requirements with no physical damage or performance degradation. It exceeds thermal requirements by operating over a 100 C temperature range (-44 C to +56 C) and has a high power handling capability allowing up to 100 W of CW input power.
NASA Technical Reports Server (NTRS)
Piotrowski, W. S.; Raue, J. E.
1984-01-01
Design, development, and tests are described for two single-pole-double-throw latching waveguide ferrite switches: a K-band switch in WR-42 waveguide and a Ka-band switch in WR-28 waveguide. Both switches have structurally simple junctions, mechanically interlocked without the use of bonding materials; they are impervious to the effects of thermal, shock, and vibration stresses. Ferrite material for the Ka-band switch with a proper combination of magnetic and dielectric properties was available and resulted in excellent low loss, wideband performance. The high power handling requirement of the K-band switch limited the choice of ferrite to nickel-zinc compositions with adequate magnetic properties, but with too low relative dielectric constant. The relative dielectric constant determines the junction dimensions for given frequency responses. In this case the too low value unavoidably leads to a larger than optimum junction volume, increasing the insertion loss and restricting the operating bandwidth. Efforts to overcome the materials-related difficulties through the design of a composite junction with increased effective dielectric properties efforts to modify the relative dielectric constant of nickel-zinc ferrite are examined.
NASA Technical Reports Server (NTRS)
Kahn, Jon B. (Inventor)
1988-01-01
A mechanism is disclosed for the docking of a spacecraft to a space station where a connection for transfer of personnel and equipment is desired. The invention comprises an active docking structure on a spacecraft and a passive docking structure on the station. The passive structure includes a docking ring mounted on a tunnel structure fixed to the space station. The active structure includes a docking ring carried by an actuator-attenuator devices, each attached at one end to the ring and at its other end in the spacecraft payload bay. The devices respond to command signals for moving the docking ring between a stowed position in the spacecraft to a deployed position suitable for engagement with the docking ring. The devices comprise means responsive to signals of sensed loadings to absorb impact energy and retraction means for drawing the coupled spacecraft and station into final docked configuration and moving the tunnel structure to a berthed position in the spacecraft. Latches couple the spacecraft and space station upon contact of the docking rings and latches establish a structural tie between the spacecraft when retracted.
Quick-release connector module
NASA Technical Reports Server (NTRS)
Sedig, Albert R. (Inventor)
1995-01-01
A multi-bay electrical connector is described, of the type that has a frame (12, FIG. 2 ) with cavities (14) that each holds a separate module 20, which enables quick withdrawal of a single module from the frame and its quick replacement. A lock arm (42) is slidable along a first side (50) of a first cavity, and has at least one lock lug (80). A first module has a barrier part (70) that lies inward of the lock lug, which prevents outward movement of the first module out of the frame cavity. The lock arm can be moved to an unlocked position wherein the barrier part on the module lies inward of a gap (84) in the lock arm to permit the module to be pulled out of the frame cavity and later inserted therein. A latch (54) is slidable on the frame in directions (A, B) perpendicular to the sliding movement of the lock arm, and has an abutment (112, FIG. 5 ) that abuts a shoulder (114) on the lock arm to keep the lock arm in its unlocked position until the latch is released.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ohsawa, T.; Ikeda, S.; Hanyu, T.
The robustness of data load of metal–oxide–semiconductor/magnetic tunnel junction (MOS/MTJ) hybrid latches at power-on is examined by using Monte Carlo simulation with the variations in magnetoresistances for MTJs and in threshold voltages for MOSFETs involved in 90 nm technology node. Three differential pair type spin-transfer-torque-magnetic random access memory cells (4T2MTJ, 6T2MTJ, and 8T2MTJ) are compared for their successful data load at power-on. It is found that the 4T2MTJ cell has the largest pass area in the shmoo plot in TMR ratio (tunnel magnetoresistance ratio) and V{sub dd} in which a whole 256 kb cell array can be powered-on successfully. The minimum TMRmore » ratio for the 4T2MTJ in 0.9 V < V{sub dd} < 1.9 V is 140%, while the 6T2MTJ and the 8T2MTJ cells require TMR ratio larger than 170%.« less
Pradhan, Rajib
2014-06-10
This work proposes a scheme of all-optical XNOR/NOT logic gates based on a reflective vertical cavity semiconductor (quantum wells, QWs) saturable absorber (VCSSA). In a semiconductor Fabry-Perot cavity operated with a low-intensity resonance wavelength, both intensity-dependent saturating phase-shift and thermal phase-shift occur, which are considered in the proposed logic operations. The VCSSA-based logics are possible using the saturable behavior of reflectivity under the typical operating conditions. The low-intensity saturable reflectivity is reported for all-optical logic operations where all possible nonlinear phase-shifts are ignored. Here, saturable absorption (SA) and the nonlinear phase-shift-based all-optical XNOR/NOT gates and one-bit memory or LATCH are proposed under new operating conditions. All operations are demonstrated for a VCSSA based on InGaAs/InP QWs. These types of SA-based logic devices can be comfortably used for a signal bit rate of about 10 GHz corresponding to the carrier recovery time of the semiconductor material.
Reconfigurable Fault Tolerance for FPGAs
NASA Technical Reports Server (NTRS)
Shuler, Robert, Jr.
2010-01-01
The invention allows a field-programmable gate array (FPGA) or similar device to be efficiently reconfigured in whole or in part to provide higher capacity, non-redundant operation. The redundant device consists of functional units such as adders or multipliers, configuration memory for the functional units, a programmable routing method, configuration memory for the routing method, and various other features such as block RAM, I/O (random access memory, input/output) capability, dedicated carry logic, etc. The redundant device has three identical sets of functional units and routing resources and majority voters that correct errors. The configuration memory may or may not be redundant, depending on need. For example, SRAM-based FPGAs will need some type of radiation-tolerant configuration memory, or they will need triple-redundant configuration memory. Flash or anti-fuse devices will generally not need redundant configuration memory. Some means of loading and verifying the configuration memory is also required. These are all components of the pre-existing redundant FPGA. This innovation modifies the voter to accept a MODE input, which specifies whether ordinary voting is to occur, or if redundancy is to be split. Generally, additional routing resources will also be required to pass data between sections of the device created by splitting the redundancy. In redundancy mode, the voters produce an output corresponding to the two inputs that agree, in the usual fashion. In the split mode, the voters select just one input and convey this to the output, ignoring the other inputs. In a dual-redundant system (as opposed to triple-redundant), instead of a voter, there is some means to latch or gate a state update only when both inputs agree. In this case, the invention would require modification of the latch or gate so that it would operate normally in redundant mode, and would separately latch or gate the inputs in non-redundant mode.
Breast pain in lactating mothers.
Leung, S Sf
2016-08-01
The number of new mothers who breastfeed has increased dramatically over the last three decades. There is a concern that the present related medical service may be inadequate. Breast pain is the most common complaint among lactating mothers who seek medical help. This study aimed to investigate this problem. Medical records of women who presented with breast pain to a private clinic run by a doctor who was trained as an International Lactation Consultant were reviewed over a period of 6 months in 2015. Most patients were self-referred after chatting online. Assessment included characteristics and duration of pain, treatment prior to consultation, feeding practices, mother's diet, and breast examination. Any site of blockage was identified and relieved. Those with persistent pain were given antibiotics. When there were signs of abscess or abscess that could not be drained, they were referred to a breast surgeon. A total of 69 patients were seen of whom 45 had been breastfeeding for more than 1 month. Pain was experienced for longer than 7 days in 22 women. Antifungal or antibacterial treatment had been unsuccessful in 31 women prior to consultation. The diagnoses were engorgement in five women, blocked duct in 35, mastitis in 13, breast abscess in six, poor positioning and latch in seven, nipple cracks in two, and skin infection in one. Oral antibiotics were prescribed to 21 patients and local antifungal treatment was given to one patient only. Blocked duct was the most common cause of breast pain in lactating mothers. Without prompt relief it is possible that it will progress to mastitis/breast abscess or the mother may discontinue breastfeeding. This may be a suitable time for Hong Kong to set up one or more public full-time breastfeeding clinics to provide a better service to lactating mothers and to facilitate professional training and research.
Societal and Family Situations in the U.S.A. That Affect Children's Pro-Social Behavior.
ERIC Educational Resources Information Center
Jambor, Tom
This paper discusses social and emotional development during childhood and adolescence in the United States, focusing on factors that affect children's prosocial behavior and the role of parents in promoting such behavior. It is argued that changing family structures, including the growth of single parent families and "latch-key" children, along…
NASA Technical Reports Server (NTRS)
Hall, William A.
1990-01-01
Slave microprocessors in multimicroprocessor computing system contains modified circuit cards programmed via bus connecting master processor with slave microprocessors. Enables interactive, microprocessor-based, single-loop control. Confers ability to load and run program from master/slave bus, without need for microprocessor development station. Tristate buffers latch all data and information on status. Slave central processing unit never connected directly to bus.
Building a Community of Literacy Practice with Young Adults with Intellectual Disabilities.
ERIC Educational Resources Information Center
Moni, Karen B.
This paper describes the activities and outcomes of LATCH-ON (Literacy and Technology-Hands On), a literacy program for young adults with Down Syndrome based at the University of Queensland in Australia. The program's aims are to support literacy as a desirable and valued aspect in the students' quality of life through developing communication in…
Weird Science: Further Thoughts on the STEM Educational Challenge
ERIC Educational Resources Information Center
Halfond, Jay A.
2010-01-01
The author notes that the sciences are now something one must latch onto early and successfully as a teenager, and endure against all odds. This pivotal point requires maturity and even myopia--delayed gratification and voluntary dorkiness--traits not common in the young. As a nation, Americans are losing their hegemony in the sciences. In just…
Federal Register 2010, 2011, 2012, 2013, 2014
2011-03-14
... the bearings and lockbase retainer in the door latch assembly, relocating and adjusting of the sensor target and the sensor proximity switch, and testing to ensure positive door locking and corrective action... retainer, and relocating and adjusting the sensor target and the sensor proximity switch to forward...
76 FR 54405 - Airworthiness Directives; The Boeing Company Model 747 Airplanes
Federal Register 2010, 2011, 2012, 2013, 2014
2011-09-01
... fracture were initiated by fatigue and propagated by a combination of fatigue and stress corrosion. We are... stress corrosion. One operator reported a fractured latch pin of the lower sill of the aft lower lobe... by fatigue and propagated by a combination of fatigue and stress corrosion. We are issuing this AD to...
Federal Register 2010, 2011, 2012, 2013, 2014
2011-10-12
.... Therefore, * * * this [Canadian] directive is issued to require rework of the cockpit door striker plate and... these Do these actions-- serial numbers-- 8-52-54, Revision A, dated 003 through 407 Rework the cockpit... AD rework the cockpit door striker plate and replace the latch block, in accordance with the...
75 FR 7370 - Federal Motor Vehicle Safety Standards; Door Locks and Door Retention Components
Federal Register 2010, 2011, 2012, 2013, 2014
2010-02-19
... at (202) 366-2990. For legal issues, contact Ms. Sarah Alves, Office of the Chief Counsel, by... have secondary latching positions and to remove the option for a visual door closure warning system... test plates; and, S4, to reinstate an exclusion of doors equipped with wheelchair lift systems. This...
75 FR 78594 - Airworthiness Directives; The Boeing Company Model 777-200 Series Airplanes
Federal Register 2010, 2011, 2012, 2013, 2014
2010-12-16
... which a T/R is installed with a design change known as ``Commonality T/R,'' which is common to Model 777... Airworthiness Directives; The Boeing Company Model 777-200 Series Airplanes AGENCY: Federal Aviation... certain Model 777-200 series airplanes. This AD requires installing a new insulation blanket on the latch...
Federal Register 2010, 2011, 2012, 2013, 2014
2011-09-07
... will facilitate egress after an accident, including leaving the lavatory door locked open during taxi... (foam or equivalent), such as Ensolite. (c) Thoracic Trauma. Testing with a Side Impact Dummy (SID), as... pounds. (g) Emergency Evacuation. When occupied, the lavatory door must be latched open for takeoff and...
Magnetically Operated Holding Plate And Ball-Lock Pin
NASA Technical Reports Server (NTRS)
Monford, Leo G., Jr.
1992-01-01
Magnetically operated holding plate and ball-locking-pin mechanism part of object attached to, or detached from second object. Mechanism includes tubular housing inserted in hole in second object. Plunger moves inside tube forcing balls to protrude from sides. Balls prevent tube from sliding out of second object. Simpler, less expensive than motorized latches; suitable for robotics applications.
Expedition 34 Crewmembers in the Cupola Module
2012-11-27
ISS034-E-010953 (27 Nov. 2012) --- NASA astronaut Kevin Ford (lower right), Expedition 34 commander; along with Russian cosmonauts Evgeny Tarelkin (left) and Oleg Novitskiy, both flight engineers, pose for a photo in the Cupola of the International Space Station. The Canadarm2 robotic arm's Latching End Effector (LEE) is visible through a window in the background.
Galileo and the Pendulum: Latching on to Time
ERIC Educational Resources Information Center
Machamer, Peter; Hepburn, Brian
2004-01-01
Galileo changed the very concepts or categories by which natural philosophy could deal with matter and motion. Central to these changes was his introduction of time as a fundamental concept. He worked with the pendulum and with the inclined plane to discover his new concept of motion. Both of these showed him that acceleration and time were…
A High Power Solid State Circuit Breaker for Military Hybrid Electric Vehicle Applications
2012-08-01
the SSCB to isolate a fault, breaker opening is latched and can be reset to reclose the breaker via remote logic input. SSCB state and health...rated load current (125 A). Figure 10 shows that after the SSCB detects a fault and opens, it can also be repeatedly reclosed remotely to attempt to
Temperature Dependence Of Single-Event Effects
NASA Technical Reports Server (NTRS)
Coss, James R.; Nichols, Donald K.; Smith, Lawrence S.; Huebner, Mark A.; Soli, George A.
1990-01-01
Report describes experimental study of effects of temperature on vulnerability of integrated-circuit memories and other electronic logic devices to single-event effects - spurious bit flips or latch-up in logic state caused by impacts of energetic ions. Involved analysis of data on 14 different device types. In most cases examined, vulnerability to these effects increased or remain constant with temperature.
LSI logic for phase-control rectifiers
NASA Technical Reports Server (NTRS)
Dolland, C.
1980-01-01
Signals for controlling phase-controlled rectifier circuit are generated by combinatorial logic than can be implemented in large-scale integration (LSI). LSI circuit saves space, weight, and assembly time compared to previous controls that employ one-shot multivibrators, latches, and capacitors. LSI logic functions by sensing three phases of ac power source and by comparing actual currents with intended currents.
Kılcı, Hanife; Çoban, Ayden
2016-05-01
The research was conducted to determine the correlation between breastfeeding success in the early postpartum period and the perception of self-efficacy in breastfeeding and breast problems in late postpartum. This analytic and cross-sectional research was carried out at Aydın Obstetrics and Gynecology and Children's Diseases Hospital. Three hundred twenty-seven primipara mothers who had delivered a single baby of healthy term at 37 or more gestational weeks with no previous experience with breastfeeding and who agreed to cooperate participated in the research. The mothers' mean gestational week of delivery was 39.25 ± 1.10 weeks, and it was found that 56.0% had delivered by cesarean section and 57.0% had started to breastfeed immediately after the birth. The mothers' LATCH mean score was 6.55 ± 0.86; their postnatal breastfeeding self-efficacy mean score was found to be 59.10 ± 7.21. Mothers who had high success in breastfeeding at early postpartum were found to experience fewer problems with their breasts (Z = -2.65, p < 0.05), gave birth by vaginal delivery (Z = -2.88, p < 0.05), and had not received anesthesia during the delivery (Z = -2.52, p < 0.05). In the correlation analysis, it was seen that mothers with high success in breastfeeding also had high self-efficacy scores (r = 0.210, p = 0.003). The results of the research indicated that breastfeeding success in the early postpartum period reduced breast problems and increased the perception of breastfeeding self-efficacy in the late postpartum period.
The sail wing windmill and its adaptation for use in rural India
NASA Technical Reports Server (NTRS)
Sherman, M. M.
1973-01-01
An 8 meter-diameter prototype sail wing windmill is reported that uses a one meter-diameter bullock cartwheel to which three bamboo poles are latched in a triangular pattern with overlapping ends, to form the airframe for cloth sails. This device lifts 300 pounds to a height of 20 feet in one minute in a 10 mph wind.
Quinby, Joseph D [Albuquerque, NM; Hall, Clarence S [Albuquerque, NM
2008-06-24
In a security apparatus for securing an electrical connector, a plug may be fitted for insertion into a connector receptacle compliant with a connector standard. The plug has at least one aperture adapted to engage at least one latch in the connector receptacle. An engagement member is adapted to partially extend through at least one aperture and lock to at least one structure within the connector receptacle.
Reading as a Pastime: Competition for Time in the Elementary School Classroom.
ERIC Educational Resources Information Center
Fowler, William R.
Reading as a pastime is basic to creativity and intellectual mind expansion as well as to the appropriate development of listening skills. Reasons for the decline of listening and communication skills can be attributed in part to misuse of media, to latch-key children, to decreased support from parents for reading at home, to lack of sufficient…
Federal Register 2010, 2011, 2012, 2013, 2014
2012-05-17
... to consumers and would not impair a consumer's ability to locate the lower anchorages. (2) Paragraph... consumers' ability to find the LATCH anchorages. While anchor bars are permitted to be as short as 25 mm in... longitudinal vertical plane tangent to the side of the anchorage bar. If a person were to probe the seat bight...
Expedition 34 Crewmembers in the Cupola Module
2012-11-27
ISS034-E-010955 (27 Nov. 2012) --- NASA astronaut Kevin Ford (lower right), Expedition 34 commander; along with Russian cosmonauts Evgeny Tarelkin (left) and Oleg Novitskiy, both flight engineers, are partially silhouetted as they pose for a photo in the Cupola of the International Space Station. The Canadarm2 robotic arm's Latching End Effector (LEE) is visible through a window in the background.
Programmable Image Processing Element.
1980-11-01
appicaIOn IS g-ivenl Ill A parallel ss OIL irmnat . Ilece. thle block diagramm of- [iguire 3 is modifwid to chanlge the 1iput data frmM pl)JIll oiit to...is slownl In I iguie -42. -1h1 breaid- board oi~s of, nine iniput latche\\,. niruc pifdle-ini seri:il-oiit shl’t reitcs I fast 5 1-’ 1 2--ilt
49 CFR 567.4 - Requirements for manufacturers of motor vehicles.
Code of Federal Regulations, 2011 CFR
2011-10-01
..., or the door edge that meets the door-latch post, next to the driver's seating position, or if none of... applicable Federal motor vehicle safety, bumper, and theft prevention standards in effect on the date of... standards in effect on the date of manufacture shown above.” The expression “U.S.” or “U.S.A.” may be...
49 CFR 567.4 - Requirements for manufacturers of motor vehicles.
Code of Federal Regulations, 2012 CFR
2012-10-01
..., or the door edge that meets the door-latch post, next to the driver's seating position, or if none of... applicable Federal motor vehicle safety, bumper, and theft prevention standards in effect on the date of... standards in effect on the date of manufacture shown above.” The expression “U.S.” or “U.S.A.” may be...
49 CFR 567.4 - Requirements for manufacturers of motor vehicles.
Code of Federal Regulations, 2014 CFR
2014-10-01
..., or the door edge that meets the door-latch post, next to the driver's seating position, or if none of... applicable Federal motor vehicle safety, bumper, and theft prevention standards in effect on the date of... standards in effect on the date of manufacture shown above.” The expression “U.S.” or “U.S.A.” may be...
NASA Technical Reports Server (NTRS)
Wilson, John C.
1995-01-01
Aerodynamic plates stop litter from spinning during hoisting by helicopter. Features of proposed litter-spinning retarders include convenience of deployment and independence from ground restraint. Retarder plate(s) folded flat against bottom of litter during storage or while litter is loaded. Plate(s) held in storage position by latch that releases manually or automatically as litter is hoisted. Upon release, springs move plates into deployed position.
Robust mitotic entry is ensured by a latching switch.
Tuck, Chloe; Zhang, Tongli; Potapova, Tamara; Malumbres, Marcos; Novák, Béla
2013-01-01
Cell cycle events are driven by Cyclin dependent kinases (CDKs) and by their counter-acting phosphatases. Activation of the Cdk1:Cyclin B complex during mitotic entry is controlled by the Wee1/Myt1 inhibitory kinases and by Cdc25 activatory phosphatase, which are themselves regulated by Cdk1:Cyclin B within two positive circuits. Impairing these two feedbacks with chemical inhibitors induces a transient entry into M phase referred to as mitotic collapse. The pathology of mitotic collapse reveals that the positive circuits play a significant role in maintaining the M phase state. To better understand the function of these feedback loops during G2/M transition, we propose a simple model for mitotic entry in mammalian cells including spatial control over Greatwall kinase phosphorylation. After parameter calibration, the model is able to recapture the complex and non-intuitive molecular dynamics reported by Potapova et al. (Potapova et al., 2011). Moreover, it predicts the temporal patterns of other mitotic regulators which have not yet been experimentally tested and suggests a general design principle of cell cycle control: latching switches buffer the cellular stresses which accompany cell cycle processes to ensure that the transitions are smooth and robust.
Release mechanism for releasing and reattaching experiments on the Space Shuttle
NASA Technical Reports Server (NTRS)
Clark, A. V.
1980-01-01
The release mechanism (REM) unlatches an experiment so that it can be moved about inside and outside the shuttle bay by the remote manipulator system (RMS), and then reattaches it to the REM base. Operated from the crew compartment after the RMS has been attached to the experiment, the REM releases the experiment by an electric motor driving a gear train and linkage which extracts four pins from holes in four plates. Electrical connectors on the REM are disengaged by the mechanical action of the structural pins retracting from the plates. When the REM releases the experiment, an unlatched indicator is actuated in the crew compartment, and then the experiment can be moved by using the RMS. To reattach the experiment to the REM, the RMS places the experiment with REM attachment angles against the flat, smooth surface of the REM; then the RMS moves the experiment into position for latchup. Actuation of an electric motor drives the four pins into the four holes in the plates. When fully latched, a switch actuated by the motion of the linkage, shuts the electric motor off and gives an indication to the crew compartment that the REM is latched.
Surge Pressure Mitigation in the Global Precipitation Measurement Mission Core Propulsion System
NASA Technical Reports Server (NTRS)
Scroggins, Ashley R.; Fiebig, Mark D.
2014-01-01
The Global Precipitation Measurement (GPM) mission is an international partnership between NASA and JAXA whose Core spacecraft performs cutting-edge measurements of rainfall and snowfall worldwide and unifies data gathered by a network of precipitation measurement satellites. The Core spacecraft's propulsion system is a blowdown monopropellant system with an initial hydrazine load of 545 kg in a single composite overwrapped propellant tank. At launch, the propulsion system contained propellant in the tank and manifold tubes upstream of the latch valves, with low-pressure helium gas in the manifold tubes downstream of the latch valves. The system had a relatively high beginning-of- life pressure and long downstream manifold lines; these factors created conditions that were conducive to high surge pressures. This paper discusses the GPM project's approach to surge mitigation in the propulsion system design. The paper describes the surge testing program and results, with discussions of specific difficulties encountered. Based on the results of surge testing and pressure drop analyses, a unique configuration of cavitating venturis was chosen to mitigate surge while minimizing pressure losses during thruster maneuvers. This paper concludes with a discussion of overall lessons learned with surge pressure testing for NASA Goddard spacecraft programs.
NASA Technical Reports Server (NTRS)
Kahn, Jon B. (Inventor)
1990-01-01
A mechanism for the docking of a space vehicle to a space station where a connection for transfer of personnel and equipment is desired. The invention comprises an active docking structure on a space vehicle 10 and a passive docking structure on a station 11. The passive structure includes a docking ring 50 mounted on a tunnel structure 35 fixed to the space station. The active structure including a docking ring 18 carried by actuator-attenuator devices 20, each attached at one end to the ring 18 and at its other end in the vehicle's payload bay 12. The devices 20 respond to command signals for moving the docking ring 18 between a stowed position in the space vehicle to a deployed position suitable for engagement with the docking ring 50. The devices 20 comprise means responsive to signals of sensed loadings to absorb impact energy and retraction means for drawing the coupled space vehicle and station into final docked configuration and moving the tunnel structure to a berthed position in the space vehicle 10. Latches 60 couple the space vehicle and space station upon contact of docking rings 18 and 50 and latches 41-48 establish a structural tie between the spacecraft when retracted.
The integration of novel EAP-based Braille cells for use in a refreshable tactile display
NASA Astrophysics Data System (ADS)
Di Spigna, N.; Chakraborti, P.; Winick, D.; Yang, P.; Ghosh, T.; Franzon, P.
2010-04-01
Structures demonstrating the viability of both the hydraulic and latching Braille dot, and the dielectric elastomer fiber Braille dot have been fabricated and characterized. A hydraulic proof-of-concept structure has achieved the necessary volumetric change required to lift a Braille dot over 0.5mm at voltages under 1000V and at speeds under 100ms. Long bimorphs have been fabricated that demonstrate large tip displacements over 2mm that could be used to mechanically latch the Braille rod in the 'up' position to achieve the force requirement. The addition of radial prestrain in dielectric elastomer tubes has reduced the wall thickness and directed the strain in the axial direction which has had a dramatic impact on their resulting characteristics. The required bias voltage for the dielectric elastomer fiber Braille dot has been reduced from 15.5kV to 8.75kV while the Braille head tip displacement of a fabricated prototype has almost tripled on average and now also exceeds the required displacement for a refreshable Braille display. Finally, potential solutions to the current shortcomings of both designs in meeting all of the requirements for such a display are discussed.
Harvey, Andrew C.; Ribich, William A.; Marinaccio, Paul J.; Sawaf, Bernard E.
1987-12-01
A separable fastener system has a first separable member that includes a series of metal hook sheets disposed in stacked relation that defines an array of hook elements on its broad surface. Each hook sheet is a planar metal member of uniform thickness and has a body portion with a series of hook elements formed along one edge of the body. Each hook element includes a stem portion, a deflecting surface portion, and a latch portion. Metal spacer sheets are disposed between the hook sheets and may be varied in thickness and in number to control the density of the hook elements on the broad surface of the first fastener member. The hook and spacer sheets are secured together in stacked relation. A second fastener member has a surface of complementary engaging elements extending along its broad surface which are releasably interengageable with the hook elements of the first fastener member, the deflecting surfaces of the hook elements of the first fastener member tending to deflect hook engaging portions of the second fastener member and the latch portions of the hook elements of the first fastener member engaging portions of the second fastener member in fastening relation.
Design and implementation of low power clock gated 64-bit ALU on ultra scale FPGA
NASA Astrophysics Data System (ADS)
Gupta, Ashutosh; Murgai, Shruti; Gulati, Anmol; Kumar, Pradeep
2016-03-01
64-bit energy efficient Arithmetic and Logic Unit using negative latch based clock gating technique is designed in this paper. The 64-bit ALU is designed using multiplexer based full adder cell. We have designed a 64-bit ALU with a gated clock. We have used negative latch based circuit for generating gated clock. This gated clock is used to control the multiplexer based 64-bit ALU. The circuit has been synthesized on kintex FPGA through Xilinx ISE Design Suite 14.7 using 28 nm technology in Verilog HDL. The circuit has been simulated on Modelsim 10.3c. The design is verified using System Verilog on QuestaSim in UVM environment. We have achieved 74.07%, 92. 93% and 95.53% reduction in total clock power, 89.73%, 91.35% and 92.85% reduction in I/Os power, 67.14%, 62.84% and 74.34% reduction in dynamic power and 25.47%, 29.05% and 46.13% reduction in total supply power at 20 MHz, 200 MHz and 2 GHz frequency respectively. The power has been calculated using XPower Analyzer tool of Xilinx ISE Design Suite 14.3.
Optical switch based on thermocapillarity
NASA Astrophysics Data System (ADS)
Sakata, Tomomi; Makihara, Mitsuhiro; Togo, Hiroyoshi; Shimokawa, Fusao; Kaneko, Kazumasa
2001-11-01
Space-division optical switches are essential for the protection, optical cross-connects (OXCs), and optical add/drop multiplexers (OADMs) needed in future fiber-optic communication networks. For applications in these areas, we proposed a thermocapillarity switch called oil-latching interfacial-tension variation effect (OLIVE) switch. An OLIVE switch is a micro-mechanical optical switch fabricated on planar lightwave circuits (PLC) using micro-electro-mechanical systems (MEMS) technology. It consists of a crossing waveguide that has a groove at each crossing point and a pair of microheaters. The groove is partially filled with the refractive-index-matching liquid, and optical signals are switched according to the liquid's position in the groove, i.e., whether it is passing straight through the groove or reflecting at the sidewall of the groove. The liquid is driven by thermocapillarity and latched by capillarity. Using the total internal reflection to switch the optical path, the OLIVE switch exhibits excellent optical characteristics, such as high transparency (insertion loss: < 2 dB), high extinction ratio (> 50 dB), and low crosstalk (< -50 dB). Moreover, since this switch has a simple structure and bi-stability, it has wide variety of applications in wavelength division multiplexing (WDM) networks.
Rotatable electric cable connecting system
NASA Technical Reports Server (NTRS)
Manges, D. R. (Inventor)
1985-01-01
A cable reel assembly is described which is particularly adapted for, but not limited to, a system for providing electrical connection of power and data signals between an orbiter vehicle, such as a space shuttle, and a recovered satellite. The assembly is comprised of two mutually opposing ring type structures having 180 deg relative rotation with one of the structures being held in fixed position while the other structure is rotatable. Motor controlled berthing latches and umbilical cable connectors for the satellite are located on the rim of the rotatable ring structure. The electrical cable assembly is fed in two sections from the orbiter vehicle into the outer rim portion of the fixed ring structure where they are directed inwardly and attached to two concentrically coiled metal bands whose respective ends are secured to inner and outer post members of circular sets of guide pins located on opposing circular plate members, one rotatable and one fixed. The cable sections are fed out as three output cable sections through openings in the central portion of the circular plate of the rotatable ring structure where they are directed to the latches and connectors located on its rim.
Human-Computer Interaction with Medical Decisions Support Systems
NASA Technical Reports Server (NTRS)
Adolf, Jurine A.; Holden, Kritina L.
1994-01-01
Decision Support Systems (DSSs) have been available to medical diagnosticians for some time, yet their acceptance and use have not increased with advances in technology and availability of DSS tools. Medical DSSs will be necessary on future long duration space missions, because access to medical resources and personnel will be limited. Human-Computer Interaction (HCI) experts at NASA's Human Factors and Ergonomics Laboratory (HFEL) have been working toward understanding how humans use DSSs, with the goal of being able to identify and solve the problems associated with these systems. Work to date consists of identification of HCI research areas, development of a decision making model, and completion of two experiments dealing with 'anchoring'. Anchoring is a phenomenon in which the decision maker latches on to a starting point and does not make sufficient adjustments when new data are presented. HFEL personnel have replicated a well-known anchoring experiment and have investigated the effects of user level of knowledge. Future work includes further experimentation on level of knowledge, confidence in the source of information and sequential decision making.
STS-99 Flight Crew Post-Landing Press Conference
NASA Technical Reports Server (NTRS)
2000-01-01
The primary objective of the STS-99 mission was to complete high resolution mapping of large sections of the Earth's surface using the Shuttle Radar Topography Mission (SRTM), a specially modified radar system that will produced unrivaled 3-D images of the Earth's Surface. The mission was launched at 12:31 on February 11, 2000 onboard the space shuttle Endeavour. The mission was led by Commander Kevin Kregel. The crew was Pilot Dominic L. Pudwill Gorie and Mission Specialists Janet L. Kavandi, Janice E. Voss, Mamoru Mohri, the National Space Development Agency (Japanese Space Agency) and Gerhard P. J. Thiele, from DARA (German Space Agency). The shuttle landed at Kennedy on the February 22, 2000 at 5:22 CST. This tape shows a post landing press conference with the crew. Commander Kregel made a brief statement praising the crew for the mission's success and then introduced the crewmembers. The crew answered questions about the retraction of the mast. The retraction had been successful, but the latches to the canister had failed. The extreme cold may have caused the problem and a solution was proposed from ground control. If this had not worked, an EVA would have been required. The astronauts were confident in the solution to the problem, however they were ready to perform any required EVA. Mamoru Mohri answered questions from the Japanese press, speaking in English and Japanese.
T-Cell Warriors—Equipped to Kill Cancer Cells | Center for Cancer Research
When the body recognizes tumor cells as foreign, a natural immune response arises to attack them. Unfortunately, tumors have ways to evade immune surveillance systems and antitumor responses are often too weak to defeat the disease. Rather than relying on the body’s natural response, scientists can now manipulate a patient’s own immune cells so that they latch on to tumor
2001-01-01
operator. (d) Prohibited usage. (1) Equipment shall not be used in a manner that exerts sideloading stresses upon the crane or derrick boom. (2) No crane ... hooks shall be latched or otherwise secured to prevent accidental load disengagement. (f) General. (1) Operating controls. (i) Crane and derrick...when the boom is supported on a dolly. The empty hook or other attachment shall be secured. (4) Unattended cranes . The following steps shall be taken
Self-actuating grapple automatically engages and releases loads from overhead cranes
NASA Technical Reports Server (NTRS)
Froehlich, J. A.; Karastas, G. A.
1966-01-01
Two-piece grapple mechanism consisting of a lift knob secured to the load and a grapple member connected to the crane or lift automatically disengages the load from the overhead lifting device when the load contacts the ground. The key feature is the sliding collar under the lift knob which enables the grapple latch to be stripped off over the lift knob.
Linear dynamic range enhancement in a CMOS imager
NASA Technical Reports Server (NTRS)
Pain, Bedabrata (Inventor)
2008-01-01
A CMOS imager with increased linear dynamic range but without degradation in noise, responsivity, linearity, fixed-pattern noise, or photometric calibration comprises a linear calibrated dual gain pixel in which the gain is reduced after a pre-defined threshold level by switching in an additional capacitance. The pixel may include a novel on-pixel latch circuit that is used to switch in the additional capacitance.
ERIC Educational Resources Information Center
Muller, Chandra; And Others
This study explored the effects of after-school supervision on 8th graders' academic performance. Data from the National Educational Longitudinal Study of 1988 relating to a total sample size of 20,491 students (after exclusions) in 802 public and 233 private schools were analyzed. The analysis indicated that parents do not discriminate between…
Transistor Laser Optical NOR Gate for High Speed Optical Logic Processors
2017-03-20
proposes an optical bistable latch can be built with two universal photonic NOR gate circuits, which are implemented by the three-port tunneling ... Tunneling Junction Transistor Laser (TJ-TL); Optical NOR Gate. Introduction To fulfill the future national security and intelligence needs in this...two-terminal diode lasers. Three-Port Transistor Laser – an Integration of Quantum-Wells into Heterojunction Bipolar Transistor Different than
Williams, Gary L.; Goin, Jr., Jesse L.; Kirby, Patrick G.; McKenna, John P.
1997-01-01
The invention is a motorized linkage for operating a door strike. A six volt power source, controlled by a security code, rotates a small electric motor when a proper security code is given. The motor rotates a shaft which engages a coil spring. This moves a locking cam. When a catch on the locking cam separates from the locking lever catch, the latch bolt keeper may be manipulated by a user.
Code of Federal Regulations, 2012 CFR
2012-10-01
..., 14 air bags, 15 seat belts, 16 structure, 17 latch, 18 vehicle speed control, 19 tires, 20 wheels, 21...., hydraulic or air), the information required by this subsection shall be reported by each of the two brake types. If the service brake system in a vehicle is not readily characterized as either hydraulic or air...
Code of Federal Regulations, 2011 CFR
2011-10-01
..., 14 air bags, 15 seat belts, 16 structure, 17 latch, 18 vehicle speed control, 19 tires, 20 wheels, 21...., hydraulic or air), the information required by this subsection shall be reported by each of the two brake types. If the service brake system in a vehicle is not readily characterized as either hydraulic or air...
Code of Federal Regulations, 2014 CFR
2014-10-01
... train, 11 electrical, 12 exterior lighting, 13 visibility, 14 air bags, 15 seat belts, 16 structure, 17... visibility, 14 air bags, 15 seat belts, 16 structure, 17 latch, 18 vehicle speed control, 19 tires, 20 wheels... manufactured and available with more than one type of service brake system (i.e., hydraulic or air), the...
Sequential circuit design for radiation hardened multiple voltage integrated circuits
Clark, Lawrence T [Phoenix, AZ; McIver, III, John K.
2009-11-24
The present invention includes a radiation hardened sequential circuit, such as a bistable circuit, flip-flop or other suitable design that presents substantial immunity to ionizing radiation while simultaneously maintaining a low operating voltage. In one embodiment, the circuit includes a plurality of logic elements that operate on relatively low voltage, and a master and slave latches each having storage elements that operate on a relatively high voltage.
"The Most Famous Brain in the World" Performance and Pedagogy on an Amnesiac's Brain
ERIC Educational Resources Information Center
Sweaney, Katherine W.
2012-01-01
Project H.M. was just the sort of thing one might expect the Internet to latch onto: it was a live streaming video of a frozen human brain being slowly sliced apart. Users who clicked the link on Twitter or Facebook between the 2nd and 4th of December 2009 were immediately confronted with a close-up shot of the brain's interior, which was…
Intelligent magnetometer with photoelectric sampler
NASA Astrophysics Data System (ADS)
Wang, Defang; Xu, Yan; Zhu, Minjun
1991-08-01
The magnetometer described in this paper introduces a photoelectric sampler and a single-chip microcomputer, thus eliminating the error that is not eliminated in the analog circuit. The application of the photoelectric segregator and the voltage-to-frequency convertor have suppressed the interference significantly. According to the requirement of measuring the magnetic field, the function of automatic searching the latching is added. The intelligent magnetometer has higher accuracy and good temperature stability.
Radiation Status of Sub-65 nm Electronics
NASA Technical Reports Server (NTRS)
Pellish, Jonathan A.
2011-01-01
Ultra-scaled complementary metal oxide semiconductor (CMOS) includes commercial foundry capabilities at and below the 65 nm technology node Radiation evaluations take place using standard products and test characterization vehicles (memories, logic/latch chains, etc.) NEPP focus is two-fold: (1) Conduct early radiation evaluations to ascertain viability for future NASA missions (i.e. leverage commercial technology development). (2) Uncover gaps in current testing methodologies and mechanism comprehension -- early risk mitigation.
2009-08-21
CAPE CANAVERAL, Fla. – In NASA Kennedy Space Center's Orbiter Processing Facility 1, technicians begin a functional test on the orbital docking system on space shuttle Atlantis. The STS-129 mission will deliver to the International Space Station two spare gyroscopes, two nitrogen tank assemblies, two pump modules, an ammonia tank assembly and a spare latching end effector for the station's robotic arm. STS-129 is targeted to launch Nov. 12. Photo credit: NASA/Kim Shiflett
2009-08-21
CAPE CANAVERAL, Fla. – In NASA Kennedy Space Center's Orbiter Processing Facility 1, technicians prepare to test the orbital docking system on space shuttle Atlantis. The STS-129 mission will deliver to the International Space Station two spare gyroscopes, two nitrogen tank assemblies, two pump modules, an ammonia tank assembly and a spare latching end effector for the station's robotic arm. STS-129 is targeted to launch Nov. 12. Photo credit: NASA/Kim Shiflett
2009-08-21
CAPE CANAVERAL, Fla. – In NASA Kennedy Space Center's Orbiter Processing Facility 1, technicians begin testing the orbital docking system on space shuttle Atlantis. The STS-129 mission will deliver to the International Space Station two spare gyroscopes, two nitrogen tank assemblies, two pump modules, an ammonia tank assembly and a spare latching end effector for the station's robotic arm. STS-129 is targeted to launch Nov. 12. Photo credit: NASA/Kim Shiflett
Handbook of Geophysics and the Space Environment
1985-12-05
non -critical circuts may continue to function with false infortmttion. control syrstems. cati latch-up. that is. he swvitched into ain undesired miode...34. working under the auspices of Corn- remotely controllable ionosondes can provide ionospheric mission G (On the Ionosphere). a Working Group of the...Radar Aurora: Spectral Observations of Non -Two- Fremouw. E.J.. "Geometrical Control of the Ratio of In- Stream Irregularities," J. Geophys. Res., 80
ACES. Accelerated Corrosion Expert Simulator
2010-02-01
Composites Coating Systems Organic Inorganic Ceramic Materials 22 Inputs and Dimensions Xi Thickness Hardness Strength Ductility Abrasion Resistance...GPU 25 T-Handle Latch 10-Year ACT Material/ Coating Configuration Die Cast Zinc T-Handle Carbon Steel Pin CS Shank CS T-Washer Carbon Steel Dish E- coat ...CARC Zinc Plating Cadmium Plated BoltE- coat /CARC CS Panel CS Panel O-Ring E- coat /CARC Original (10-year ACT) Design Green Flag Color Qualitative
Fischer, Gary J [Albuquerque, NM
2010-08-17
The present invention provides robotic vehicles having wheeled and hopping mobilities that are capable of traversing (e.g. by hopping over) obstacles that are large in size relative to the robot and, are capable of operation in unpredictable terrain over long range. The present invention further provides combustion powered linear actuators, which can include latching mechanisms to facilitate pressurized fueling of the actuators, as can be used to provide wheeled vehicles with a hopping mobility.
Combustion powered linear actuator
Fischer, Gary J.
2007-09-04
The present invention provides robotic vehicles having wheeled and hopping mobilities that are capable of traversing (e.g. by hopping over) obstacles that are large in size relative to the robot and, are capable of operation in unpredictable terrain over long range. The present invention further provides combustion powered linear actuators, which can include latching mechanisms to facilitate pressurized fueling of the actuators, as can be used to provide wheeled vehicles with a hopping mobility.
Optically-gated Non-latched High Gain Power Device
2008-11-21
parameters such as power conversion efficiency, dv/dt and di/dt stress on PSD and electromagnetic noise emission spectrum, which depend directly on the...4. EXPERIMENTAL STUDIES ON OTPT AND OPTICAL INTENSITY MODULATION OF OTPT PARAMETERS 33 4.1 Optical source, driver, and fiber details 33 4.2...off dynamics characterizations 36 4.5. Optical intensity modulation of OTPT parameters 37 5. EXPERIMENTAL STUDIES ON HYBRID OTPT-PSD AND OPTICAL
NASA Astrophysics Data System (ADS)
Michalicek, M. Adrian; Bright, Victor M.
2001-10-01
This paper presents the design, fabrication, modeling, and testing of various arrays of cantilever micromirror devices integrated atop CMOS control electronics. The upper layers of the arrays are prefabricated in the MUMPs process and then flip-chip transferred to CMOS receiving modules using a novel latching off-chip hinge mechanism. This mechanism allows the micromirror arrays to be released, rotated off the edge of the host module and then bonded to the receiving module using a standard probe station. The hinge mechanism supports the arrays by tethers that are severed to free the arrays once bonded. The resulting devices are inherently planarized since the bottom of the first releasable MUMPs layer becomes the surface of the integrated mirror. The working devices are formed by mirror surfaces bonded to address electrodes fabricated above static memory cells on the CMOS module. These arrays demonstrate highly desirable features such as compatible address potentials, less than 2 nm of RMS roughness, approximately 1 micrometers of lateral position accuracy and the unique ability to metallize reflective surfaces without masking. Ultimately, the off-chip hinge mechanism enables very low-cost, simple, reliable, repeatable and accurate assembly of advanced MEMS and integrated microsystems without specialized equipment or complex procedures.
Research on Streamlines and Aerodynamic Heating for Unstructured Grids on High-Speed Vehicles
NASA Technical Reports Server (NTRS)
DeJarnette, Fred R.; Hamilton, H. Harris (Technical Monitor)
2001-01-01
Engineering codes are needed which can calculate convective heating rates accurately and expeditiously on the surfaces of high-speed vehicles. One code which has proven to meet these needs is the Langley Approximate Three-Dimensional Convective Heating (LATCH) code. It uses the axisymmetric analogue in an integral boundary-layer method to calculate laminar and turbulent heating rates along inviscid surface streamlines. It requires the solution of the inviscid flow field to provide the surface properties needed to calculate the streamlines and streamline metrics. The LATCH code has been used with inviscid codes which calculated the flow field on structured grids, Several more recent inviscid codes calculate flow field properties on unstructured grids. The present research develops a method to calculate inviscid surface streamlines, the streamline metrics, and heating rates using the properties calculated from inviscid flow fields on unstructured grids. Mr. Chris Riley, prior to his departure from NASA LaRC, developed a preliminary code in the C language, called "UNLATCH", to accomplish these goals. No publication was made on his research. The present research extends and improves on the code developed by Riley. Particular attention is devoted to the stagnation region, and the method is intended for programming in the FORTRAN 90 language.
Cui, Guiying; Freeman, Cody S.; Knotts, Taylor; Prince, Chengyu Z.; Kuang, Christopher; McCarty, Nael A.
2013-01-01
Previous studies have identified two salt bridges in human CFTR chloride ion channels, Arg352-Asp993 and Arg347-Asp924, that are required for normal channel function. In the present study, we determined how the two salt bridges cooperate to maintain the open pore architecture of CFTR. Our data suggest that Arg347 not only interacts with Asp924 but also interacts with Asp993. The tripartite interaction Arg347-Asp924-Asp993 mainly contributes to maintaining a stable s2 open subconductance state. The Arg352-Asp993 salt bridge, in contrast, is involved in stabilizing both the s2 and full (f) open conductance states, with the main contribution being to the f state. The s1 subconductance state does not require either salt bridge. In confirmation of the role of Arg352 and Asp993, channels bearing cysteines at these sites could be latched into a full open state using the bifunctional cross-linker 1,2-ethanediyl bismethanethiosulfonate, but only when applied in the open state. Channels remained latched open even after washout of ATP. The results suggest that these interacting residues contribute differently to stabilizing the open pore in different phases of the gating cycle. PMID:23709221
Reliability Design for Neutron Induced Single-Event Burnout of IGBT
NASA Astrophysics Data System (ADS)
Shoji, Tomoyuki; Nishida, Shuichi; Ohnishi, Toyokazu; Fujikawa, Touma; Nose, Noboru; Hamada, Kimimori; Ishiko, Masayasu
Single-event burnout (SEB) caused by cosmic ray neutrons leads to catastrophic failures in insulated gate bipolar transistors (IGBTs). It was found experimentally that the incident neutron induced SEB failure rate increases as a function of the applied collector voltage. Moreover, the failure rate increased sharply with an increase in the applied collector voltage when the voltage exceeded a certain threshold value (SEB cutoff voltage). In this paper, transient device simulation results indicate that impact ionization at the n-drift/n+ buffer boundary is a crucially important factor in the turning-on of the parasitic pnp transistor, and eventually latch-up of the parasitic thyristor causes SEB. In addition, the device parameter dependency of the SEB cutoff voltage was analytically derived from the latch-up condition of the parasitic thyristor. As a result, it was confirmed that reducing the current gain of the parasitic transistor, such as by increasing the n-drift region thickness d was effective in increasing the SEB cutoff voltage. Furthermore, `white' neutron-irradiation experiments demonstrated that suppressing the inherent parasitic thyristor action leads to an improvement of the SEB cutoff voltage. It was confirmed that current gain optimization of the parasitic transistor is a crucial factor for establishing highly reliable design against chance failures.
Capacitor charging FET switcher with controller to adjust pulse width
Mihalka, Alex M.
1986-01-01
A switching power supply includes an FET full bridge, a controller to drive the FETs, a programmable controller to dynamically control final output current by adjusting pulse width, and a variety of protective systems, including an overcurrent latch for current control. Power MOSFETS are switched at a variable frequency from 20-50 kHz to charge a capacitor load from 0 to 6 kV. A ferrite transformer steps up the DC input. The transformer primary is a full bridge configuration with the FET switches and the secondary is fed into a high voltage full wave rectifier whose output is connected directly to the energy storage capacitor. The peak current is held constant by varying the pulse width using predetermined timing resistors and counting pulses. The pulse width is increased as the capacitor charges to maintain peak current. A digital ripple counter counts pulses, and after the desired number is reached, an up-counter is clocked. The up-counter output is decoded to choose among different resistors used to discharge a timing capacitor, thereby determining the pulse width. A current latch shuts down the supply on overcurrent due to either excessive pulse width causing transformer saturation or a major bridge fault, i.e., FET or transformer failure, or failure of the drive circuitry.
Besse, Nadine; Rosset, Samuel; Zarate, Juan Jose; Ferrari, Elisabetta; Brayda, Luca; Shea, Herbert
2018-01-01
We present a fully latching and scalable 4 × 4 haptic display with 4 mm pitch, 5 s refresh time, 400 mN holding force, and 650 μm displacement per taxel. The display serves to convey dynamic graphical information to blind and visually impaired users. Combining significant holding force with high taxel density and large amplitude motion in a very compact overall form factor was made possible by exploiting the reversible, fast, hundred-fold change in the stiffness of a thin shape memory polymer (SMP) membrane when heated above its glass transition temperature. Local heating is produced using an addressable array of 3 mm in diameter stretchable microheaters patterned on the SMP. Each taxel is selectively and independently actuated by synchronizing the local Joule heating with a single pressure supply. Switching off the heating locks each taxel into its position (up or down), enabling holding any array configuration with zero power consumption. A 3D-printed pin array is mounted over the SMP membrane, providing the user with a smooth and room temperature array of movable pins to explore by touch. Perception tests were carried out with 24 blind users resulting in 70 percent correct pattern recognition over a 12-word tactile dictionary.
An experimental study of fault propagation in a jet-engine controller. M.S. Thesis
NASA Technical Reports Server (NTRS)
Choi, Gwan Seung
1990-01-01
An experimental analysis of the impact of transient faults on a microprocessor-based jet engine controller, used in the Boeing 747 and 757 aircrafts is described. A hierarchical simulation environment which allows the injection of transients during run-time and the tracing of their impact is described. Verification of the accuracy of this approach is also provided. A determination of the probability that a transient results in latch, pin or functional errors is made. Given a transient fault, there is approximately an 80 percent chance that there is no impact on the chip. An empirical model to depict the process of error exploration and degeneration in the target system is derived. The model shows that, if no latch errors occur within eight clock cycles, no significant damage is likely to happen. Thus, the overall impact of a transient is well contained. A state transition model is also derived from the measured data, to describe the error propagation characteristics within the chip, and to quantify the impact of transients on the external environment. The model is used to identify and isolate the critical fault propagation paths, the module most sensitive to fault propagation and the module with the highest potential of causing external pin errors.
Preliminary GN&C Design for the On-Orbit Autonomous Assembly of Nanosatellite Demonstration Mission
NASA Technical Reports Server (NTRS)
Pei, Jing; Walsh, Matt; Roithmayr, Carlos; Karlgaard, Chris; Peck, Mason; Murchison, Luke
2017-01-01
Small spacecraft autonomous rendezvous and docking (ARD) is an essential technology for future space structure assembly missions. The On-orbit Autonomous Assembly of Nanosatellites (OAAN) team at NASA Langley Research Center (LaRC) intends to demonstrate the technology to autonomously dock two nanosatellites to form an integrated system. The team has developed a novel magnetic capture and latching mechanism that allows for docking of two CubeSats without precise sensors and actuators. The proposed magnetic docking hardware not only provides the means to latch the CubeSats, but it also significantly increases the likelihood of successful docking in the presence of relative attitude and position errors. The simplicity of the design allows it to be implemented on many CubeSat rendezvous missions. Prior to demonstrating the docking subsystem capabilities on orbit, the GN&C subsystem should have a robust design such that it is capable of bringing the CubeSats from an arbitrary initial separation distance of as many as a few thousand kilometers down to a few meters. The main OAAN Mission can be separated into the following phases: 1) Launch, checkout, and drift, 2) Far-Field Rendezvous or Drift Recovery, 3) Proximity Operations, 4) Docking. This paper discusses the preliminary GN&C design and simulation results for each phase of the mission.
Martin, A.D.
1986-05-09
Method and apparatus are provided for generating an output pulse following a trigger pulse at a time delay interval preset with a resolution which is high relative to a low resolution available from supplied clock pulses. A first lumped constant delay provides a first output signal at predetermined interpolation intervals corresponding to the desired high resolution time interval. Latching circuits latch the high resolution data to form a first synchronizing data set. A selected time interval has been preset to internal counters and corrected for circuit propagation delay times having the same order of magnitude as the desired high resolution. Internal system clock pulses count down the counters to generate an internal pulse delayed by an internal which is functionally related to the preset time interval. A second LCD corrects the internal signal with the high resolution time delay. A second internal pulse is then applied to a third LCD to generate a second set of synchronizing data which is complementary with the first set of synchronizing data for presentation to logic circuits. The logic circuits further delay the internal output signal with the internal pulses. The final delayed output signal thereafter enables the output pulse generator to produce the desired output pulse at the preset time delay interval following input of the trigger pulse.
1976-11-01
system. b. Read different program configurations to reconfigure the software during flight. c. Write Digital Integrated Test System (DITS) results...associated witn > inor C):l.e Event must be Unlatched. The sole difference between a Latched ana an lnratcrec Condition is that upon the Scheduling...Table. Furthermore, the block of pointers for one Minor Cycle may be wholly contained witnir the Diock of ocinters for a different Minor Cycle. For
Hatch Cover Slides Through Hatch
NASA Technical Reports Server (NTRS)
Alton, Charles; Okane, James H.
1989-01-01
Hatch cover for pressurized vessel provides tight seal but opened quickly from either side. In opening or closing, cover sweeps out relatively little volume within vessel, so it does not hinder movement of people or objects from vessel to outside or placement of people or objects near hatch. Cover uses internal pressure to create seal when closed. Design of cover eliminates leakage paths, and cover immune to hazards of sudden decompression or jamming when bolts and latches fail.
2009-09-25
CAPE CANAVERAL, Fla. – In Orbiter Processing Facility 1 at NASA's Kennedy Space Center in Florida, space shuttle Atlantis' payload bay door is closing. The designated shuttle for the STS-129 mission, Atlantis will deliver to the International Space Station two spare gyroscopes, two nitrogen tank assemblies, two pump modules, an ammonia tank assembly and a spare latching end effector for the station's robotic arm. Atlantis is targeted to launch Nov. 12. Photo credit: NASA/Jack Pfaller
2009-09-25
CAPE CANAVERAL, Fla. – In Orbiter Processing Facility 1 at NASA's Kennedy Space Center in Florida, space shuttle Atlantis' payload bay doors are being closed. The designated shuttle for the STS-129 mission, Atlantis will deliver to the International Space Station two spare gyroscopes, two nitrogen tank assemblies, two pump modules, an ammonia tank assembly and a spare latching end effector for the station's robotic arm. Atlantis is targeted to launch Nov. 12. Photo credit: NASA/Jack Pfaller
2009-09-25
CAPE CANAVERAL, Fla. – In Orbiter Processing Facility 1 at NASA's Kennedy Space Center in Florida, space shuttle Atlantis' payload bay door is closing. The designated shuttle for the STS-129 mission, Atlantis will deliver to the International Space Station two spare gyroscopes, two nitrogen tank assemblies, two pump modules, an ammonia tank assembly and a spare latching end effector for the station's robotic arm. Atlantis is targeted to launch Nov. 12. Photo credit: NASA/Jack Pfaller
Miniaturized double latching solenoid valve
NASA Technical Reports Server (NTRS)
Smith, James T. (Inventor)
2010-01-01
A valve includes a generally elongate pintle; a spacer having a rounded surface that bears against the pintle; a bulbous tip fixed to the spacer; and a hollow, generally cylindrical collar fixed to the pintle, the collar enclosing the spacer and the tip and including an opening through which a portion of the tip extends, the opening in the collar and interior of the collar being of a size such that the tip floats therein.
2008-05-30
CAPE CANAVERAL, Fla. -- In the NASA News Center at NASA's Kennedy Space Center, Shuttle Crew Escape System Manager KC Chhipwadia describes for the media the elements of the helmet that is part of the launch and entry suit (seen on the table) used by shuttle crews during their missions. He is holding onto the bar that latches to secure the closed visor. The helmet provides oxygen when needed plus a communication system. Photo credit: NASA/Amanda Diller
NASA Astrophysics Data System (ADS)
Retsky, Michael
2008-04-01
Explosively formed projectiles (EFP) are a major problem in terrorism and asymmetrical warfare. EFPs are often triggered by ordinary infrared motion detectors. A potential weak link is that such electronics are not hardened to ionizing radiation and can latch-up or enter other inoperative states after exposure to a single short event of ionizing radiation. While these can often be repaired with a power restart, they also can produce shorts and permanent damage. A problem of course is that we do not want to add radiation exposure to the long list of war related hazards. Biological systems are highly sensitive to integrated dosage but show no particular sensitivity to short pulses. There may be a way to generate short pulsed subsoil radiation to deactivate concealed electronics without introducing radiation hazards to military personnel and civilian bystanders. Electron beams of 30 MeV that can be produced by portable linear accelerators (linacs) propagate >20 m in air and 10-12 cm in soil. X-radiation is produced by bremsstrahlung and occurs subsoil beneath the point of impact and is mostly forward directed. Linacs 1.5 m long can produce 66 MWatt pulses of subsoil x-radiation 1 microsecond or less in duration. Untested as yet, such a device could be mounted on a robotic vehicle that precedes a military convoy and deactivates any concealed electronics within 10-20 meters on either side of the road.
Ahmed, Azza H
2010-01-01
The preterm birth rate has been increasing steadily during the past two decades. Up to two thirds of this increase has been attributed to the increasing rate of late preterm births (34 to < 37 gestational weeks). The advantages of breastfeeding for premature infants appear to be even greater than for term infants; however, establishing breastfeeding in late-preterm infants is frequently more problematic. Because of their immaturity, late preterm infants may have less stamina; difficulty with latch, suck, and swallow; temperature instability; increased vulnerability to infection; hyperbilirubinemia, and more respiratory problems than the full-term infant. Late preterm infants usually are treated as full term and discharged within 48 hours of birth, so pediatric nurse practitioners in primary care settings play a critical role in promoting breastfeeding through early assessment and detection of breastfeeding difficulties and by providing anticipatory guidance related to breastfeeding and follow-up. The purpose of this article is to describe the developmental and physiologic immaturity of late preterm infants and to highlight the role of pediatric nurse practitioners in primary care settings in supporting and promoting breastfeeding for late preterm infants.
Programmable Aperture with MEMS Microshutter Arrays
NASA Technical Reports Server (NTRS)
Moseley, Samuel; Li, Mary; Kutyrev, Alexander; Kletetschka, Gunther; Fettig, Rainer
2011-01-01
A microshutter array (MSA) has been developed for use as an aperture array for multi-object selections in James Webb Space Telescope (JWST) technology. Light shields, molybdenum nitride (MoN) coating on shutters, and aluminum/aluminum oxide coatings on interior walls are put on each shutter for light leak prevention, and to enhance optical contrast. Individual shutters are patterned with a torsion flexure that permits shutters to open 90 deg. with a minimized mechanical stress concentration. The shutters are actuated magnetically, latched, and addressed electrostatically. Also, micromechanical features are tailored onto individual shutters to prevent stiction. An individual shutter consists of a torsion hinge, a shutter blade, a front electrode that is coated on the shutter blade, a backside electrode that is coated on the interior walls, and a magnetic cobalt-iron coating. The magnetic coating is patterned into stripes on microshutters so that shutters can respond to an external magnetic field for the magnetic actuation. A set of column electrodes is placed on top of shutters, and a set of row electrodes on sidewalls is underneath the shutters so that they can be electrostatically latched open. A linear permanent magnet is aligned with the shutter rows and is positioned above a flipped upside-down array, and sweeps across the array in a direction parallel to shutter columns. As the magnet sweeps across the array, sequential rows of shutters are rotated from their natural horizontal orientation to a vertical open position, where they approach vertical electrodes on the sidewalls. When the electrodes are biased with a sufficient electrostatic force to overcome the mechanical restoring force of torsion bars, shutters remain latched to vertical electrodes in their open state. When the bias is removed, or is insufficient, the shutters return to their horizontal, closed positions. To release a shutter, both the electrode on the shutter and the one on the back wall where the shutter sits are grounded. The shutters with one or both ungrounded electrodes are held open. Sub-micron bumps underneath light shields and silicon ribs on back walls are the two features to prevent stiction. These features ensure that the microshutter array functions properly in mechanical motions. The MSA technology can be used primarily in multi-object imaging and spectroscopy, photomask generation, light switches, and in the stepper equipment used to make integrated circuits and MEMS (microelectromechanical systems) devices.
Utilizing the Digital Fingerprint Methodology for Secure Key Generation
2010-03-01
circuits. 2.2.2. Arbiter PUF 2.2.1 Arbiter PUF Description Figure 3 represents the arbiter PUF circuitry designed by Suh and Devadas [4]. The D latch...Reliability The results of Suh and Devadas ‟s experiments on the arbiter PUF circuit showed that when the arbiter circuit output was measured for the...and Devada pointed out that this low percentage was the result of not laying out their circuit symmetrically as it appears in the idealized
1982-03-01
Aircraft Company ARECAaSOENT CSR Ground Systems Group Task 007 Fullerton, California 92634 Project No. R1023 I$. =OTRS4.IWmOr SP NAnE lAD ABDASE it. REPORT...HMA feed mechanism, multiple type test sockets or adapters, and a localized UUT vessel for functional tests at temperature. The engineering model AP...test excluding (deactivated) microprocessor. * Models UUT and test adapter as a ROM. Independent latches or registers from interconnecting ports to
Yu, Ruomeng; Wu, Wenzhuo; Pan, Caofeng; Wang, Zhaona; Ding, Yong; Wang, Zhong Lin
2015-02-04
Using polarization charges created at the metal-cadmium sulfide interface under strain to gate/modulate electrical transport and optoelectronic processes of charge carriers, the piezo-phototronic effect is applied to process mechanical and optical stimuli into electronic controlling signals. The cascade nanowire networks are demonstrated for achieving logic gates, binary computations, and gated D latches to store information carried by these stimuli. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
STS-109 MS Linnehan on aft flight deck with laser rangefinder
2002-03-03
STS109-346-011 (3 March 2002) --- Astronaut Richard M. Linnehan, STS-109 mission specialist, uses a laser ranging device designed to measure the range between two spacecraft. Linnehan positioned himself on the cabin's aft flight deck as the Space Shuttle Columbia approached the Hubble Space Telescope. A short time later, the STS-109 crew captured and latched down the giant telescope in the vehicle's cargo bay for several days of work on the Hubble.
The design and testing of a memory metal actuated boom release mechanism
NASA Technical Reports Server (NTRS)
Powley, D. G.; Brook, G. B.
1979-01-01
A boom latch and release mechanism was designed, manufactured and tested, based on a specification for the ISEE-B satellite mechanism. From experimental results obtained, it is possible to calculate the energy available and the operating torques which can be achieved from a torsional shape memory element in terms of the reversible strain induced by prior working. Some guidelines to be followed when designing mechanisms actuated by shape memory elements are included.
2002-03-05
STS109-E-5642 (5 March 2002) --- Astronaut James H. Newman, mission specialist, peers into Columbia's crew cabin during a brief break in work on the Hubble Space Telescope (HST), latched down just a few feet behind him in Columbia's cargo bay. Astronauts Newman and Michael J. Massimino are making their first extravehicular activity (EVA) of the mission, following the act of two other crewmembers on the previous day. The image was recorded with a digital still camera.
Single-Event Effect Testing of the Linear Technology LTC6103HMS8#PBF Current Sense Amplifier
NASA Technical Reports Server (NTRS)
Yau, Ka-Yen; Campola, Michael J.; Wilcox, Edward
2016-01-01
The LTC6103HMS8#PBF (henceforth abbreviated as LTC6103) current sense amplifier from Linear Technology was tested for both destructive and non-destructive single-event effects (SEE) using the heavy-ion cyclotron accelerator beam at Lawrence Berkeley National Laboratory (LBNL) Berkeley Accelerator Effects (BASE) facility. During testing, the input voltages and output currents were monitored to detect single event latch-up (SEL) and single-event transients (SETs).
1990-04-01
MISSION REQUIREMENTS. THE MATRIX MATERIALS PROPOSED FOR THIS PHASE I INVESTIGATION ARE POLYETHER ETHER KETON (PEEK) AND POLYBUTELENE TERAPHTHALATE (PBT...NOISE AND RADIATION HARD, PARTICULARLY RADIATION HARD AGAINST NEUTRON IRRADIATION. A PROPOSAL IS MADE FOR THE DEVELOPMENT OF AN INNOVATIVE TECHNOLOGY...AND RADIATION -HARD APPLICATIONS. THE SOI WAFER WILL ELIMINATE LATCH-UP EFFECTS, REDUCE NEUTRON -CAPTURE VOLUME AND PROVIDE ELECTRICAL ISOLATION FOR
Mechanical end joint system for structural column elements
NASA Technical Reports Server (NTRS)
Bush, H. G.; Wallsom, R. E. (Inventor)
1982-01-01
A mechanical end joint system, useful for the transverse connection of strut elements to a common node, comprises a node joint half with a semicircular tongue and groove, and a strut joint half with a semicircular tongue and groove. The two joint halves are engaged transversely and the connection is made secure by the inherent physical property characteristics of locking latches and/or by a spring-actioned shaft. A quick release mechanism provides rapid disengagement of the joint halves.
Erectable/deployable concepts for large space system technology
NASA Technical Reports Server (NTRS)
Agan, W. E.
1980-01-01
Erectable/deployable space structure concepts particularly relating to the development of a science and applications space platform are presented. Design and operating features for an automatic coupler clevis joint, a side latching detent joint, and a module-to-module auto lock coupler are given. An analysis of the packaging characteristics of stacked subassembly, single fold, hybrid, and double fold concepts is given for various platform structure configurations. Payload carrier systems and assembly techniques are also discussed.
Chattopadhyay, Tanay
2010-10-01
A flip-flop (FF) is a kind of latch and the simplest form of memory device, which stores various values either temporarily or permanently. Optical FF memories form a fundamental building block for all-optical packet switches in next-generation communication networks. An all-optical clocked delay FF using a single terahertz optical asymmetric demultiplexer-based interferometric switch is proposed and described. Numerical simulation results are also reported.
Code of Federal Regulations, 2010 CFR
2010-10-01
... S16.3.3.1.9 and S16.3.3.1.10. S16.3.5.4 Remove all slack from the lap belt. Pull the upper torso... device, introduce the maximum amount of slack into the upper torso belt that is recommended by the..., place the Type 2 manual belt around the test dummy and fasten the latch. Remove all slack from the lap...
Electrothermal Microactuators With Peg Drive Improve Performance for Brain Implant Applications
Anand, Sindhu; Sutanto, Jemmy; Baker, Michael S.; Okandan, Murat; Muthuswamy, Jit
2013-01-01
This paper presents a new actuation scheme for in-plane bidirectional translation of polysilicon microelectrodes. The new Chevron-peg actuation scheme uses microelectromechanical systems (MEMS) based electrothermal microactuators to move microelectrodes for brain implant applications. The design changes were motivated by specific needs identified by the in vivo testing of an earlier generation of MEMS microelectrodes that were actuated by the Chevron-latch type of mechanism. The microelectrodes actuated by the Chevron-peg mechanism discussed here show improved performance in the following key areas: higher force generation capability (111 μN per heat strip compared to 50 μN), reduced power consumption (91 mW compared to 360 mW), and reliable performance with consistent forward and backward movements of microelectrodes. Failure analysis of the Chevron-latch and the Chevron-peg type of actuation schemes showed that the latter is more robust to wear over four million cycles of operation. The parameters for the activation waveforms for Chevron-peg actuators were optimized using statistical analysis. Waveforms with a 1-ms time period and a 1-Hz frequency of operation showed minimal error between the expected and the actual movement of the microelectrodes. The new generation of Chevron-peg actuators and microelectrodes are therefore expected to enhance the longevity and performance of implanted microelectrodes in the brain. [2011-0341] PMID:24431926
Biological Signal Processing with a Genetic Toggle Switch
Hillenbrand, Patrick; Fritz, Georg; Gerland, Ulrich
2013-01-01
Complex gene regulation requires responses that depend not only on the current levels of input signals but also on signals received in the past. In digital electronics, logic circuits with this property are referred to as sequential logic, in contrast to the simpler combinatorial logic without such internal memory. In molecular biology, memory is implemented in various forms such as biochemical modification of proteins or multistable gene circuits, but the design of the regulatory interface, which processes the input signals and the memory content, is often not well understood. Here, we explore design constraints for such regulatory interfaces using coarse-grained nonlinear models and stochastic simulations of detailed biochemical reaction networks. We test different designs for biological analogs of the most versatile memory element in digital electronics, the JK-latch. Our analysis shows that simple protein-protein interactions and protein-DNA binding are sufficient, in principle, to implement genetic circuits with the capabilities of a JK-latch. However, it also exposes fundamental limitations to its reliability, due to the fact that biological signal processing is asynchronous, in contrast to most digital electronics systems that feature a central clock to orchestrate the timing of all operations. We describe a seemingly natural way to improve the reliability by invoking the master-slave concept from digital electronics design. This concept could be useful to interpret the design of natural regulatory circuits, and for the design of synthetic biological systems. PMID:23874595
High-Fidelity Single-Shot Readout for a Spin Qubit via an Enhanced Latching Mechanism
NASA Astrophysics Data System (ADS)
Harvey-Collard, Patrick; D'Anjou, Benjamin; Rudolph, Martin; Jacobson, N. Tobias; Dominguez, Jason; Ten Eyck, Gregory A.; Wendt, Joel R.; Pluym, Tammy; Lilly, Michael P.; Coish, William A.; Pioro-Ladrière, Michel; Carroll, Malcolm S.
2018-04-01
The readout of semiconductor spin qubits based on spin blockade is fast but suffers from a small charge signal. Previous work suggested large benefits from additional charge mapping processes; however, uncertainties remain about the underlying mechanisms and achievable fidelity. In this work, we study the single-shot fidelity and limiting mechanisms for two variations of an enhanced latching readout. We achieve average single-shot readout fidelities greater than 99.3% and 99.86% for the conventional and enhanced readout, respectively, the latter being the highest to date for spin blockade. The signal amplitude is enhanced to a full one-electron signal while preserving the readout speed. Furthermore, layout constraints are relaxed because the charge sensor signal is no longer dependent on being aligned with the conventional (2,0)-(1,1) charge dipole. Silicon donor-quantum-dot qubits are used for this study, for which the dipole insensitivity substantially relaxes donor placement requirements. One of the readout variations also benefits from a parametric lifetime enhancement by replacing the spin-relaxation process with a charge-metastable one. This provides opportunities to further increase the fidelity. The relaxation mechanisms in the different regimes are investigated. This work demonstrates a readout that is fast, has a one-electron signal, and results in higher fidelity. It further predicts that going beyond 99.9% fidelity in a few microseconds of measurement time is within reach.
2017-10-04
Tomorrow on the first spacewalk of Expedition 53, astronauts will install a new latching end effector on the International Space Station’s robotic arm, Canadarm2, to keep that invaluable piece of hardware ready to support the station’s continuing mission. Take a quick look back at the invaluable role played by the “big arm” in assembling the space station and keeping it flying. _______________________________________ FOLLOW THE SPACE STATION! Twitter: https://twitter.com/Space_Station Facebook: https://www.facebook.com/ISS Instagram: https://instagram.com/iss/
NASA Technical Reports Server (NTRS)
Carreno, Victor A.; Choi, G.; Iyer, R. K.
1990-01-01
A simulation study is described which predicts the susceptibility of an advanced control system to electrical transients resulting in logic errors, latched errors, error propagation, and digital upset. The system is based on a custom-designed microprocessor and it incorporates fault-tolerant techniques. The system under test and the method to perform the transient injection experiment are described. Results for 2100 transient injections are analyzed and classified according to charge level, type of error, and location of injection.
2009-07-16
CAPE CANAVERAL, Fla. – In the Space Station Processing Facility at NASA's Kennedy Space Center in Florida, technicians keep watch as the control moment gyroscope is lowered toward an EXPRESS Logistics Carrier. The carrier is part of the STS-129 payload on space shuttle Atlantis, which will deliver to the International Space Station two spare gyroscopes, two nitrogen tank assemblies, two pump modules, an ammonia tank assembly and a spare latching end effector for the station's robotic arm. STS-129 is targeted to launch Nov. 12 . Photo credit: NASA/Jack Pfaller
2009-07-16
CAPE CANAVERAL, Fla. – In the Space Station Processing Facility at NASA's Kennedy Space Center in Florida, technicians keep watch as the control moment gyroscope is moved toward an EXPRESS Logistics Carrier. The carrier is part of the STS-129 payload on space shuttle Atlantis, which will deliver to the International Space Station two spare gyroscopes, two nitrogen tank assemblies, two pump modules, an ammonia tank assembly and a spare latching end effector for the station's robotic arm. STS-129 is targeted to launch Nov. 12 . Photo credit: NASA/Jack Pfaller
1997-07-06
The undeployed Sojourner rover is seen still latched to a lander petal in this image, taken by the Imager for Mars Pathfinder (IMP) on Sol 1, the lander's first day on Mars. Portions of a petal and deflated airbag are in the foreground. The rectangular rock at right has been dubbed "Flat top," and may be a possible object of study for Sojourner's Alpha Proton X-Ray Spectrometer (APXS) instrument. The mismatched portion of image at left is a misregistered section of data. http://photojournal.jpl.nasa.gov/catalog/PIA00631
Deployable M-braced truss structure
NASA Technical Reports Server (NTRS)
Mikulas, M. M., Jr. (Inventor); Rhodes, M. D. (Inventor)
1986-01-01
A deployable M-braced truss structure, efficiently packaged into a compact stowed position and expandable to an operative position at the use site is described. The M-braced configuration effectively separates tension compression and shear in the structure and permits efficient structural design. Both diagonals and longerons telescope from an M-braced base unit and deploy either pneumatically, mechanically by springs or cables, or by powered reciprocating mechanisms. Upon full deployment, the diagonals and longerons lock into place with a simple latch mechanism.
2009-08-17
CAPE CANAVERAL, Fla. – In the Space Station Processing Facility at NASA's Kennedy Space Center in Florida, the nitrogen tank assembly is moved toward the Express Logistics Carrier 1, or ELC-1. The carrier is part of the STS-129 payload on space shuttle Atlantis, which will deliver to the International Space Station two spare gyroscopes, two nitrogen tank assemblies, two pump modules, an ammonia tank assembly and a spare latching end effector for the station's robotic arm. STS-129 is targeted to launch Nov. 12. Photo credit: NASA/Jim Grossmann
2009-08-17
CAPE CANAVERAL, Fla. – In the Space Station Processing Facility at NASA's Kennedy Space Center in Florida, the nitrogen tank assembly is lowered onto the Express Logistics Carrier 1, or ELC-1. The carrier is part of the STS-129 payload on space shuttle Atlantis, which will deliver to the International Space Station two spare gyroscopes, two nitrogen tank assemblies, two pump modules, an ammonia tank assembly and a spare latching end effector for the station's robotic arm. STS-129 is targeted to launch Nov. 12. Photo credit: NASA/Jim Grossmann
2009-08-14
CAPE CANAVERAL, Fla. – In NASA Kennedy Space Center's Space Station Processing Facility, an overhead crane moves the Express Logistics Carrier, or ELC, to a rotation stand. The carrier is part of the STS-129 payload on space shuttle Atlantis, which will deliver to the International Space Station two spare gyroscopes, two nitrogen tank assemblies, two pump modules, an ammonia tank assembly and a spare latching end effector for the station's robotic arm. STS-129 is targeted to launch Nov. 12. Photo credit: NASA/Kim Shiflett
2009-08-17
CAPE CANAVERAL, Fla. – In the Space Station Processing Facility at NASA's Kennedy Space Center in Florida, the nitrogen tank assembly is lowered toward the Express Logistics Carrier 1, or ELC-1. The carrier is part of the STS-129 payload on space shuttle Atlantis, which will deliver to the International Space Station two spare gyroscopes, two nitrogen tank assemblies, two pump modules, an ammonia tank assembly and a spare latching end effector for the station's robotic arm. STS-129 is targeted to launch Nov. 12. Photo credit: NASA/Jim Grossmann
2009-03-21
CAPE CANAVERAL, Fla. – Inside the Space Station Processing Facility at NASA's Kennedy Space Center in Florida, a crane carries the EXPRESS Logistics Carrier toward a stand. The carrier is part of the payload on space shuttle Atlantis, which will deliver to the International Space Station components including two spare gyroscopes, two nitrogen tank assemblies, two pump modules, an ammonia tank assembly and a spare latching end effector for the station's robotic arm. STS-129 is targeted to launch Nov. 12. Photo credit: NASA/Tim Jacobs
2009-03-21
CAPE CANAVERAL, Fla. – Inside the Space Station Processing Facility at NASA's Kennedy Space Center in Florida, a crane lowers the EXPRESS Logistics Carrier onto a stand. The carrier is part of the payload on space shuttle Atlantis, which will deliver to the International Space Station components including two spare gyroscopes, two nitrogen tank assemblies, two pump modules, an ammonia tank assembly and a spare latching end effector for the station's robotic arm. STS-129 is targeted to launch Nov. 12. Photo credit: NASA/Tim Jacobs
2009-03-21
CAPE CANAVERAL, Fla. – Inside the Space Station Processing Facility at NASA's Kennedy Space Center in Florida, technicians check the EXPRESS Logistics Carrier for the STS-129 mission after its cover was removed. The carrier is part of the payload on space shuttle Atlantis, which will deliver to the International Space Station components including two spare gyroscopes, two nitrogen tank assemblies, two pump modules, an ammonia tank assembly and a spare latching end effector for the station's robotic arm. STS-129 is targeted to launch Nov. 12. Photo credit: NASA/Tim Jacobs
2009-03-21
CAPE CANAVERAL, Fla. – Inside the Space Station Processing Facility at NASA's Kennedy Space Center in Florida, a strongback crane is lowered toward the EXPRESS Logistics Carrier to lift it to a stand. The carrier is part of the payload on space shuttle Atlantis, which will deliver to the International Space Station components including two spare gyroscopes, two nitrogen tank assemblies, two pump modules, an ammonia tank assembly and a spare latching end effector for the station's robotic arm. STS-129 is targeted to launch Nov. 12. Photo credit: NASA/Tim Jacobs
2009-03-21
CAPE CANAVERAL, Fla. – Inside the Space Station Processing Facility at NASA's Kennedy Space Center in Florida, a crane lifts the EXPRESS Logistics Carrier tomove it to a stand. The carrier is part of the payload on space shuttle Atlantis, which will deliver to the International Space Station components including two spare gyroscopes, two nitrogen tank assemblies, two pump modules, an ammonia tank assembly and a spare latching end effector for the station's robotic arm. STS-129 is targeted to launch Nov. 12. Photo credit: NASA/Tim Jacobs
2009-03-21
CAPE CANAVERAL, Fla. – Inside the Space Station Processing Facility at NASA's Kennedy Space Center in Florida, technicians remove the cover from around the EXPRESS Logistics Carrier for the STS-129 mission. The carrier is part of the payload on space shuttle Atlantis, which will deliver to the International Space Station components including two spare gyroscopes, two nitrogen tank assemblies, two pump modules, an ammonia tank assembly and a spare latching end effector for the station's robotic arm. STS-129 is targeted to launch Nov. 12. Photo credit: NASA/Tim Jacobs
2009-03-21
CAPE CANAVERAL, Fla. – The truck carrying the EXPRESS Logistics Carrier for the STS-129 mission arrives at the Space Station Processing Facility at NASA's Kennedy Space Center in Florida. The carrier is part of the payload on space shuttle Atlantis, which will deliver to the International Space Station components including two spare gyroscopes, two nitrogen tank assemblies, two pump modules, an ammonia tank assembly and a spare latching end effector for the station's robotic arm. STS-129 is targeted to launch Nov. 12. Photo credit: NASA/Tim Jacobs
Femtojoule-scale all-optical latching and modulation via cavity nonlinear optics.
Kwon, Yeong-Dae; Armen, Michael A; Mabuchi, Hideo
2013-11-15
We experimentally characterize Hopf bifurcation phenomena at femtojoule energy scales in a multiatom cavity quantum electrodynamical (cavity QED) system and demonstrate how such behaviors can be exploited in the design of all-optical memory and modulation devices. The data are analyzed by using a semiclassical model that explicitly treats heterogeneous coupling of atoms to the cavity mode. Our results highlight the interest of cavity QED systems for ultralow power photonic signal processing as well as for fundamental studies of mesoscopic nonlinear dynamics.
Helmet latching and attaching ring
NASA Technical Reports Server (NTRS)
Chase, E. W.; Viikinsalo, S. J. (Inventor)
1970-01-01
A neck ring releasably secured to a pressurized garment carries an open-ended ring normally in the engagement position fitted into an annular groove and adapted to fit into a complementary annular groove formed in a helmet. Camming means formed on the inner surface at the end of the helmet engages the open-ended ring to retract the same and allow for one motion donning even when the garment is pressurized. A projection on the end of the split ring is engageable to physically retract the split ring.
NASA Technical Reports Server (NTRS)
Culbertson, Philip, Jr. (Inventor)
1997-01-01
An environmental protective suit used for hazardous clean-up or space applications includes a suitlock docking mechanism that allows for easy egress and ingress of a crew member between a sealed vessel and a possibly contaminated environment. The suitlock docking mechanism comprises a single actuator that controls latches which, in turn, respectfully control rack and pinion assemblies that allow for easy removal and attachment of a life support equipment enclosure shell to the environmental protective suit or to the vehicle from which the operator performs his/her duties.
STS-109 MS Linnehan with laser range finder on aft flight deck
2002-03-02
STS109-E-5003 (3 March 2002) --- Astronaut Richard M. Linnehan, mission specialist, uses a laser ranging device designed to measure the range between two spacecraft. Linnehan positioned himself on the cabin's aft flight deck as the Space Shuttle Columbia approached the Hubble Space Telescope. A short time later, the STS-109 crew captured and latched down the giant telescope in the vehicle's cargo bay for several days of work on the Hubble. The image was recorded with a digital still camera.
STS-109 MS Linnehan with laser range finder on aft flight deck
2002-03-02
STS109-E-5002 (3 March 2002) --- Astronaut Richard M. Linnehan, mission specialist, uses a laser ranging device designed to measure the range between two spacecraft. Linnehan positioned himself on the cabin's aft flight deck as the Space Shuttle Columbia approached the Hubble Space Telescope. A short time later, the STS-109 crew captured and latched down the giant telescope in the vehicle's cargo bay for several days of work on the Hubble. The image was recorded with a digital still camera.
Relatchable launch restraint mechanism for deployable booms
NASA Technical Reports Server (NTRS)
Warden, Robert M.
1990-01-01
A new Relatchable Launch Mechanism was developed which enables a deployable system to be restrained and released repeatedly rather than the normal one shot release systems of the past. The deployable systems are of the self extending type which rely on a lanyard attached to a drive motor to control the deployment and retraction. The Relatch Mechanism uses the existing drive motor to also actuate the latch. The design and kinematics of the Relatch Mechanism as used on two flight programs are described.
Breastfeeding Infants with Ankyloglossia: Insight into Mothers' Experiences.
Wong, Kevin; Patel, Punam; Cohen, Michael B; Levi, Jessica R
2017-03-01
Breastfeeding difficulty from ankyloglossia can affect both the mother and baby in a breastfeeding dyad. With renewed emphasis in today's culture on breast milk, mothers may feel increasing pressure to breastfeed, and the inability for some to do so may cause significant distress. Recently, online parenting forums have seen exponential growth; these forums allow mothers to connect with peers undergoing similar life transitions. The purpose of this study was to review online discussions regarding ankyloglossia to understand mothers' experiences with breastfeeding. We performed an ethnographic content analysis of 76 online threads and 501 posts regarding ankyloglossia based on six domains: (1) initial expectations, (2) breastfeeding complications, (3) questions, (4) diagnosis, (5) treatment, and (6) outcomes. About one-fourth of women who participated in online forum discussions had initial expectations to breastfeed, however, many found it impossible due to poor latch or pain. Concerns were frequently exacerbated by healthcare providers who reportedly missed or overlooked ankyloglossia. Although these complications made breastfeeding a challenging experience, mothers often described both subjective and physical improvements after frenotomy. Breastfeeding difficulty was a commonly voiced concern in online ankyloglossia forums. Forum analysis is an effective way to gain insight into patients' experiences, which allows providers to anticipate concerns and provides more effective counseling.
Does frenotomy improve breast-feeding difficulties in infants with ankyloglossia?
Ito, Yasuo
2014-08-01
The aim of this systematic review was to critically examine the existing literature regarding the effectiveness of tongue-tie division in infants with ankyloglossia, using the new grades of recommendations, assessment, development, and evaluation (GRADE) rating system. A clinical question was structured according to patient, intervention, comparison, and outcome, as follows: in infants with poor breast-feeding and ankyloglossia (patient), does frenotomy (intervention), compared to lactation support alone (comparison), improve feeding (outcome)? An electronic literature search was systematically conducted from databases including PubMed, Japana Centra Revuo Medicina (Igaku Chuo Zasshi), CINAHL, and Cochrane Library using the key words "ankyloglossia," "tongue-tie," "frenotomy," and/or "breast-feeding" in English and equivalent terms in Japanese. The literature search yielded four randomized clinical trials, and 12 observational studies for analysis. The quality of the literature was rated in regard to the two most important outcomes (sucking/latching, and nipple pain) and five less important outcomes (milk supply/milk production, continuation of breast-feeding, weight gain, adverse events, and dyad distress) in accordance with the GRADE system. Evidence levels of the most important outcomes were rated either A (strong evidence) or B (moderate evidence), and less important outcomes were rated C (weak evidence); every outcome consistently showed a favorable effect of frenotomy on breast-feeding. The literature review supported an overall moderate quality of evidence for the effectiveness of frenotomy for the treatment of breast-feeding difficulties in infants with ankyloglossia. No major complications from frenotomy were reported. © 2014 Japan Pediatric Society.
Douglas, Pamela; Keogh, Renee
2017-08-01
In the past decade, biological nurturing and activation of maternal and infant instincts after birth have constituted a major advance in clinical breastfeeding support. Yet, physiologic breastfeeding initiation is not enough to ensure ongoing pain-free and effective breastfeeding for many pairs. Current interventions, including "hands-off" mammalian approaches, do not improve breastfeeding outcomes, including in randomized controlled trials. Back-arching, difficulty latching or staying on the breast, and fussing at the breast are common signs of infant positional instability during breastfeeding. These cues are, however, often misdiagnosed as signs of medical conditions or oral connective tissue abnormalities, and underlying positional instability is not addressed. New clinical approaches are urgently required. This article offers a clinical approach to fit and hold (or latch and positioning)- gestalt breastfeeding, which aims to optimize positional stability and intraoral breast tissue volumes for pain-free effective breastfeeding. The word gestalt (pronounced "ger-shtolt") means a whole that is more than the sum of its parts. Gestalt breastfeeding builds on the theoretical foundations of complexity science, physiologic breastfeeding initiation, and new understandings of the biomechanics of infant suck elucidated in ultrasound studies. It also integrates simple psychological strategies from applied functional contextualism, popularly known as Acceptance and Commitment Therapy, empowering women to attend mindfully to breast sensations and their infant's cues. Gestalt breastfeeding can be reproduced for research purposes, including in comparison studies with oral surgery, and has the potential to improve breastfeeding outcomes.
Domingo-Sananes, Maria Rosa; Kapuy, Orsolya; Hunt, Tim; Novak, Bela
2011-12-27
Activation of the cyclin-dependent kinase (Cdk1) cyclin B (CycB) complex (Cdk1:CycB) in mitosis brings about a remarkable extent of protein phosphorylation. Cdk1:CycB activation is switch-like, controlled by two auto-amplification loops--Cdk1:CycB activates its activating phosphatase, Cdc25, and inhibits its inhibiting kinase, Wee1. Recent experimental evidence suggests that parallel to Cdk1:CycB activation during mitosis, there is inhibition of its counteracting phosphatase activity. We argue that the downregulation of the phosphatase is not just a simple latch that suppresses futile cycles of phosphorylation/dephosphorylation during mitosis. Instead, we propose that phosphatase regulation creates coherent feed-forward loops and adds extra amplification loops to the Cdk1:CycB regulatory network, thus forming an integral part of the mitotic switch. These network motifs further strengthen the bistable characteristic of the mitotic switch, which is based on the antagonistic interaction of two groups of proteins: M-phase promoting factors (Cdk1:CycB, Cdc25, Greatwall and Endosulfine/Arpp19) and interphase promoting factors (Wee1, PP2A-B55 and a Greatwall counteracting phosphatase, probably PP1). The bistable character of the switch implies the existence of a CycB threshold for entry into mitosis. The end of G2 phase is determined by the point where CycB level crosses the CycB threshold for Cdk1 activation.
Tylko, Suzanne; Locey, Caitlin M.; Garcia-Espana, J. Felipe; Arbogast, Kristy B.; Maltese, Matthew R.
2013-01-01
The purpose of this study was to compare the dynamic response of rear-facing child restraint systems (RFCRS) installed on the CMVSS 213 sled bench and a selection of vehicle seats. Thirty-six sled tests were conducted: three models of rear facing CRS with an anthropomorphic test device (ATD) representing a 12 month old child (CRABI) were affixed via lower anchors (LATCH), 3 point belt without CRS base, and 3 point belt with CRS base to one of three vehicle seats or the CMVSS 213 bench seat. All CRS were subjected to an identical sled acceleration pulse. Two types of matched pair analysis: “bench-to-vehicle” and “method of attachment” were conducted. Statistically significant differences were observed in the kinematic responses of the ATD and the CRS. This is the first study to quantify differences between the regulatory bench and vehicle seats on a system level and evaluate the influence of attachment method. Our results show that the difference in RFCRS forward excursion between 3-point belt with base and LATCH installations was between 1 and 7 percent on the bench and 22 to 76 percent on the vehicle seats. When evaluating the dynamic performance of RFCRS, the use of real vehicle seats from vehicles that commonly carry children may provide valuable insight. The findings would require further confirmation using a broader selection of RFCRS and vehicle seats, before generalizable conclusions can be drawn. PMID:24406967
FPGA for Power Control of MSL Avionics
NASA Technical Reports Server (NTRS)
Wang, Duo; Burke, Gary R.
2011-01-01
A PLGT FPGA (Field Programmable Gate Array) is included in the LCC (Load Control Card), GID (Guidance Interface & Drivers), TMC (Telemetry Multiplexer Card), and PFC (Pyro Firing Card) boards of the Mars Science Laboratory (MSL) spacecraft. (PLGT stands for PFC, LCC, GID, and TMC.) It provides the interface between the backside bus and the power drivers on these boards. The LCC drives power switches to switch power loads, and also relays. The GID drives the thrusters and latch valves, as well as having the star-tracker and Sun-sensor interface. The PFC drives pyros, and the TMC receives digital and analog telemetry. The FPGA is implemented both in Xilinx (Spartan 3- 400) and in Actel (RTSX72SU, ASX72S). The Xilinx Spartan 3 part is used for the breadboard, the Actel ASX part is used for the EM (Engineer Module), and the pin-compatible, radiation-hardened RTSX part is used for final EM and flight. The MSL spacecraft uses a FC (Flight Computer) to control power loads, relays, thrusters, latch valves, Sun-sensor, and star-tracker, and to read telemetry such as temperature. Commands are sent over a 1553 bus to the MREU (Multi-Mission System Architecture Platform Remote Engineering Unit). The MREU resends over a remote serial command bus c-bus to the LCC, GID TMC, and PFC. The MREU also sends out telemetry addresses via a remote serial telemetry address bus to the LCC, GID, TMC, and PFC, and the status is returned over the remote serial telemetry data bus.
High resolution digital delay timer
Martin, Albert D.
1988-01-01
Method and apparatus are provided for generating an output pulse following a trigger pulse at a time delay interval preset with a resolution which is high relative to a low resolution available from supplied clock pulses. A first lumped constant delay (20) provides a first output signal (24) at predetermined interpolation intervals corresponding to the desired high resolution time interval. Latching circuits (26, 28) latch the high resolution data (24) to form a first synchronizing data set (60). A selected time interval has been preset to internal counters (142, 146, 154) and corrected for circuit propagation delay times having the same order of magnitude as the desired high resolution. Internal system clock pulses (32, 34) count down the counters to generate an internal pulse delayed by an interval which is functionally related to the preset time interval. A second LCD (184) corrects the internal signal with the high resolution time delay. A second internal pulse is then applied to a third LCD (74) to generate a second set of synchronizing data (76) which is complementary with the first set of synchronizing data (60) for presentation to logic circuits (64). The logic circuits (64) further delay the internal output signal (72) to obtain a proper phase relationship of an output signal (80) with the internal pulses (32, 34). The final delayed output signal (80) thereafter enables the output pulse generator (82) to produce the desired output pulse (84) at the preset time delay interval following input of the trigger pulse (10, 12).
Quick-connect fasteners for assembling devices in space
NASA Technical Reports Server (NTRS)
Evenson, Erik E. (Inventor); Wesselski, Clarence J. (Inventor); Ruiz, Steve C. (Inventor)
1993-01-01
A quick-connect fastener of a relatively-simple straightforward design is arranged with a tubular body adapted to be engaged against an attachment fitting in coincidental alignment with an opening in that fitting. A tubular collet having flexible fingers projecting from its forward end is arranged in the fastener body to be shifted forwardly by an elongated expander member coaxially arranged within the tubular collet for advancing the collet fingers into the opening in the attachment fitting. Biasing means are arranged between the elongated expander member and a rotatable actuator which is threadedly mounted within the tubular collet so as to be rotated for urging the expander member into engagement with the collet fingers. A first coupling member is arranged on the rotatable actuator to be accessible from outside of the fastener so that a second coupling member on the distal end of a flexible shaft can be introduced into the fastener body and coupled to the first coupling member to enable a typical actuating tool coupled to the shaft outside of the fastener body to be operated for advancing the outwardly-enlarged ends of the collet fingers into the opening in the attachment fitting and thereafter rotating the actuator member to expand the fingers within the opening for releasably latching the fastener to that attachment fitting. Upon expansion of the collet fingers, the biasing means impose a biasing force on the expander to releasably retain the fingers in their latching positions.
Miniature electrically operated diaphragm valve
Adkins, Douglas R.; Spletzer, Barry L.; Wong, Chungnin C.; Frye-Mason, Gregory C.; Fischer, Gary J.; Hesketh, Peter J.
2001-01-01
The present invention provides a miniature electrically operated valve that can stand off significant pressures, that can be inexpensively produced, and that can be made to operate without continuous electrical power. A valve according to the present invention comprises a housing and a beam mounted with the housing. A diaphragm mounted with the housing forms a sealed fluid volume. An electromagnetic energy source, such as an electromagnetic coil, mounts with the housing and when energized urges the beam in one direction. The beam can be urged in the opposing direction by passive means or by reversing the polarity of the electromagnetic energy source or by a second electromagnetic energy source. Two fluid ports mount with the housing. A first fluid port mounts so that, as the beam is urged in one direction or the opposite, the beam urges the diaphragm to move between engaging and substantially sealing the fluid port and disengaging and not substantially sealing the fluid port. A seat can be mounted with the diaphragm to aid in sealing the fluid port. Latching mechanisms such as permanent magnets can be mounted so that the valve remains in the open or closed positions without continuous electrical power input. Fluid can flow through the housing between the two fluid ports when the diaphragm does not seal the first fluid port, but can be prevented from flowing by urging the beam so that the diaphragm seals the first fluid port. Various embodiments accommodate various latching mechanisms, electromagnetic energy sources, number of fluid ports, and diaphragm design considerations.
Magnetic docking aid for orbiter to ISS docking
NASA Technical Reports Server (NTRS)
Schneider, William C.; Nagy, Kornel; Schliesing, John A.
1996-01-01
The present docking system for the Orbiter uses mechanical capture latches that are actuated by contact forces. The forces are generated when the two approaching masses collide at the docking mechanism. There is always a trade-off between having high enough momentum to effect capture and low enough momentum to avoid structural overload or unacceptable angular displacements. The use of the present docking system includes a contact thrusting maneuver that causes high docking loads to be included into Space Station. A magnetic docking aid has been developed to reduce the load s during docking. The magnetic docking aid is comprised of two extendible booms that are attached adjacent to the docking structure with electromagnets attached on the end of the boom. On the mating vehicle, two steel plates are attached. As the Orbiter approaches Space Station, the booms are extended, and the magnets attach to the actuated (without thrusting), by slowly driving the extendible booms to the stowed position, thus reacting the load into the booms. This results in a docking event that has lower loads induced into Space Station structure. This method also greatly simplifies the Station berthing tasks, since the Shuttle Remote Manipulation System (SRMS) arm need only place the element to be berthed on the magnets (no load required), rather than firing the Reaction Control System (RCS) jets to provide the required force for capture latch actuation. The Magnetic Docking Aid was development testing on a six degree-of-freedom (6 DOF) system at JSC.
Chen, Jiann-Jong; Kung, Che-Min
2010-09-01
The communication speed between components is far from satisfactory. To achieve high speed, simple control system configuration, and low cost, a new on-chip all-digital three-phase dc/ac power inverter using feedforward and frequency control techniques is proposed. The controller of the proposed power inverter, called the shift register, consists of six-stage D-latch flip-flops with a goal of achieving low-power consumption and area efficiency. Variable frequency is achieved by controlling the clocks of the shift register. One advantage regarding the data signal (D) and the common clock (CK) is that, regardless of the phase difference between the two, all of the D-latch flip-flops are capable of delaying data by one CK period. To ensure stability, the frequency of CK must be six times higher than that of D. The operation frequency of the proposed power inverter ranges from 10 Hz to 2 MHz, and the maximum output loading current is 0.8 A. The prototype of the proposed circuit has been fabricated with TSMC 0.35 μm 2P4M CMOS processes. The total chip area is 2.333 x 1.698 mm2. The three-phase dc/ac power inverter is applicable in uninterrupted power supplies, cold cathode fluorescent lamps, and motors, because of its ability to convert the dc supply voltage into the three-phase ac power sources.
Dynamic analysis of Apollo-Salyut/Soyuz docking
NASA Technical Reports Server (NTRS)
Schliesing, J. A.
1972-01-01
The use of a docking-system computer program in analyzing the dynamic environment produced by two impacting spacecraft and the attitude control systems is discussed. Performance studies were conducted to determine the mechanism load and capture sensitivity to parametric changes in the initial impact conditions. As indicated by the studies, capture latching is most sensitive to vehicle angular-alinement errors and is least sensitive to lateral-miss error. As proved by load-sensitivity studies, peak loads acting on the Apollo spacecraft are considerably lower than the Apollo design-limit loads.
2009-07-16
CAPE CANAVERAL, Fla. – In the Space Station Processing Facility at NASA's Kennedy Space Center in Florida, technicians keep watch as the control moment gyroscope is lifted from its stand. It will be moved to an EXPRESS Logistics Carrier. The carrier is part of the STS-129 payload on space shuttle Atlantis, which will deliver to the International Space Station two spare gyroscopes, two nitrogen tank assemblies, two pump modules, an ammonia tank assembly and a spare latching end effector for the station's robotic arm. STS-129 is targeted to launch Nov. 12 . Photo credit: NASA/Jack Pfaller
2009-08-12
CAPE CANAVERAL, Fla. – In the Space Station Processing Facility at NASA's Kennedy Space Center in Florida, a control moment gyroscope is lifted by crane above an EXPRESS Logistics Carrier on which it will be installed for flight. The carrier is part of the STS-129 payload on space shuttle Atlantis, which will deliver to the International Space Station two spare gyroscopes, two nitrogen tank assemblies, two pump modules, an ammonia tank assembly and a spare latching end effector for the station's robotic arm. STS-129 is targeted to launch Nov. 12. Photo credit: NASA/Jim Grossmann
2009-07-16
CAPE CANAVERAL, Fla. – In the Space Station Processing Facility at NASA's Kennedy Space Center in Florida, technicians keep watch as the control moment gyroscope is lifted past the Node 3 Tranquility module to an EXPRESS Logistics Carrier. The carrier is part of the STS-129 payload on space shuttle Atlantis, which will deliver to the International Space Station two spare gyroscopes, two nitrogen tank assemblies, two pump modules, an ammonia tank assembly and a spare latching end effector for the station's robotic arm. STS-129 is targeted to launch Nov. 12 . Photo credit: NASA/Jack Pfaller
20th Aerospace Mechanisms Symposium. Revised
NASA Technical Reports Server (NTRS)
1986-01-01
The proceedings of the 20th Aerospace Mechanisms Symposium, hosted by the NASA Lewis Research Center, Cleveland, Ohio, on May 7-9, 1986, is documented herein. During the 3 days, 23 technical papers were presented by experts from the United States and Western Europe. A panel discussion by an International group of experts on future directions In mechanisms was also presented; this discussion, however, is not documented herein. The technical topics addressed included deployable structures, electromagnetic devices, tribology, thermal/mechanical/hydraulic actuators, latching devices, positioning mechanisms, robotic manipulators, and computerized mechanisms synthesis.
1977-08-30
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2009-08-17
CAPE CANAVERAL, Fla. – In the Space Station Processing Facility at NASA's Kennedy Space Center in Florida, technicians prepare to lift the nitrogen tank assembly to move it to the Express Logistics Carrier 1, or ELC-1. The carrier is part of the STS-129 payload on space shuttle Atlantis, which will deliver to the International Space Station two spare gyroscopes, two nitrogen tank assemblies, two pump modules, an ammonia tank assembly and a spare latching end effector for the station's robotic arm. STS-129 is targeted to launch Nov. 12. Photo credit: NASA/Jim Grossmann
2009-08-17
CAPE CANAVERAL, Fla. – In the Space Station Processing Facility at NASA's Kennedy Space Center in Florida, technicians watch closely as an overhead crane lifts the nitrogen tank assembly to move it to the Express Logistics Carrier 1, or ELC-1. The carrier is part of the STS-129 payload on space shuttle Atlantis, which will deliver to the International Space Station two spare gyroscopes, two nitrogen tank assemblies, two pump modules, an ammonia tank assembly and a spare latching end effector for the station's robotic arm. STS-129 is targeted to launch Nov. 12. Photo credit: NASA/Jim Grossmann
2009-08-17
CAPE CANAVERAL, Fla. – In the Space Station Processing Facility at NASA's Kennedy Space Center in Florida, technicians check the nitrogen tank assembly before lifting and moving it to the Express Logistics Carrier 1, or ELC-1. The carrier is part of the STS-129 payload on space shuttle Atlantis, which will deliver to the International Space Station two spare gyroscopes, two nitrogen tank assemblies, two pump modules, an ammonia tank assembly and a spare latching end effector for the station's robotic arm. STS-129 is targeted to launch Nov. 12. Photo credit: NASA/Jim Grossmann
2009-08-17
CAPE CANAVERAL, Fla. – In the Space Station Processing Facility at NASA's Kennedy Space Center in Florida, technicians check the nitrogen tank assembly closely as an overhead crane lifts and moves it to the Express Logistics Carrier 1, or ELC-1. The carrier is part of the STS-129 payload on space shuttle Atlantis, which will deliver to the International Space Station two spare gyroscopes, two nitrogen tank assemblies, two pump modules, an ammonia tank assembly and a spare latching end effector for the station's robotic arm. STS-129 is targeted to launch Nov. 12. Photo credit: NASA/Jim Grossmann
2009-08-17
CAPE CANAVERAL, Fla. – In the Space Station Processing Facility at NASA's Kennedy Space Center in Florida, technicians check the nitrogen tank assembly closely as an overhead crane lifts and moves it to the Express Logistics Carrier 1, or ELC-1. The carrier is part of the STS-129 payload on space shuttle Atlantis, which will deliver to the International Space Station two spare gyroscopes, two nitrogen tank assemblies, two pump modules, an ammonia tank assembly and a spare latching end effector for the station's robotic arm. STS-129 is targeted to launch Nov. 12. Photo credit: NASA/Jim Grossmann
2009-08-17
CAPE CANAVERAL, Fla. – In the Space Station Processing Facility at NASA's Kennedy Space Center in Florida, technicians check the nitrogen tank assembly closely as an overhead crane lifts and moves it to the Express Logistics Carrier 1, or ELC-1. The carrier is part of the STS-129 payload on space shuttle Atlantis, which will deliver to the International Space Station two spare gyroscopes, two nitrogen tank assemblies, two pump modules, an ammonia tank assembly and a spare latching end effector for the station's robotic arm. STS-129 is targeted to launch Nov. 12. Photo credit: NASA/Jim Grossmann
2009-08-17
CAPE CANAVERAL, Fla. – In the Space Station Processing Facility at NASA's Kennedy Space Center in Florida, technicians check the placement of the nitrogen tank assembly on the Express Logistics Carrier 1, or ELC-1. The carrier is part of the STS-129 payload on space shuttle Atlantis, which will deliver to the International Space Station two spare gyroscopes, two nitrogen tank assemblies, two pump modules, an ammonia tank assembly and a spare latching end effector for the station's robotic arm. STS-129 is targeted to launch Nov. 12. Photo credit: NASA/Jim Grossmann
2009-08-17
CAPE CANAVERAL, Fla. – In the Space Station Processing Facility at NASA's Kennedy Space Center in Florida, technicians check closely as the nitrogen tank assembly is lowered closer to the Express Logistics Carrier 1, or ELC-1. The carrier is part of the STS-129 payload on space shuttle Atlantis, which will deliver to the International Space Station two spare gyroscopes, two nitrogen tank assemblies, two pump modules, an ammonia tank assembly and a spare latching end effector for the station's robotic arm. STS-129 is targeted to launch Nov. 12. Photo credit: NASA/Jim Grossmann
2009-03-21
CAPE CANAVERAL, Fla. – Inside the Space Station Processing Facility at NASA's Kennedy Space Center in Florida, workers begin removing the shipping container from around the EXPRESS Logistics Carrier for the STS-129 mission. The carrier is part of the payload on space shuttle Atlantis, which will deliver to the International Space Station components including two spare gyroscopes, two nitrogen tank assemblies, two pump modules, an ammonia tank assembly and a spare latching end effector for the station's robotic arm. STS-129 is targeted to launch Nov. 12. Photo credit: NASA/Tim Jacobs
2009-03-21
CAPE CANAVERAL, Fla. – On the Shuttle Landing Facility at NASA's Kennedy Space Center in Florida, a truck carrying the EXPRESS Logistics Carrier for the STS-129 mission drives out of the open rear of the C-17 cargo plane. The carrier is part of the payload on space shuttle Atlantis, which will deliver to the International Space Station components including two spare gyroscopes, two nitrogen tank assemblies, two pump modules, an ammonia tank assembly and a spare latching end effector for the station's robotic arm. STS-129 is targeted to launch Nov. 12. Photo credit: NASA/Tim Jacobs
2009-03-21
CAPE CANAVERAL, Fla. – Inside the Space Station Processing Facility at NASA's Kennedy Space Center in Florida, a strongback crane is being moved to the EXPRESS Logistics Carrier to lift it to a stand. The carrier is part of the payload on space shuttle Atlantis, which will deliver to the International Space Station components including two spare gyroscopes, two nitrogen tank assemblies, two pump modules, an ammonia tank assembly and a spare latching end effector for the station's robotic arm. STS-129 is targeted to launch Nov. 12. Photo credit: NASA/Tim Jacobs
2009-03-21
CAPE CANAVERAL, Fla. – The truck carrying the EXPRESS Logistics Carrier for the STS-129 mission pulls away from the C-17 cargo plane that delivered it to NASA's Kennedy Space Center in Florida. The carrier is part of the payload on space shuttle Atlantis, which will deliver to the International Space Station components including two spare gyroscopes, two nitrogen tank assemblies, two pump modules, an ammonia tank assembly and a spare latching end effector for the station's robotic arm. STS-129 is targeted to launch Nov. 12. Photo credit: NASA/Tim Jacobs
Scaling and Single Event Effects (SEE) Sensitivity
NASA Technical Reports Server (NTRS)
Oldham, Timothy R.
2003-01-01
This paper begins by discussing the potential for scaling down transistors and other components to fit more of them on chips in order to increasing computer processing speed. It also addresses technical challenges to further scaling. Components have been scaled down enough to allow single particles to have an effect, known as a Single Event Effect (SEE). This paper explores the relationship between scaling and the following SEEs: Single Event Upsets (SEU) on DRAMs and SRAMs, Latch-up, Snap-back, Single Event Burnout (SEB), Single Event Gate Rupture (SEGR), and Ion-induced soft breakdown (SBD).
Superconducting Microwave Multivibrator Produced by Coherent Feedback
NASA Astrophysics Data System (ADS)
Kerckhoff, Joseph; Lehnert, K. W.
2012-10-01
We investigate a nonlinear coherent feedback circuit constructed from preexisting superconducting microwave devices. The network exhibits emergent bistable and astable states, and we demonstrate its operation as a latch and the frequency locking of its oscillations. While the network is tedious to model by hand, our observations agree quite well with the semiclassical dynamical model produced by a new software package (N. Tezak , arXiv:1111.3081v1 [Phil. Trans. R. Soc. A (to be published)]) that systematically interpreted an idealized schematic of the system as a quantum optic feedback network.
Remotely replaceable tokamak plasma limiter tiles
Gallix, R.
1987-12-09
U-shaped tiles placed end-to-end over a pair of parallel runners have two rods which engage L-shaped slots. A sliding bar between the runners has grooves with clips to retain the rods pressed into receiving legs of the L-shaped slots in the runners. Sliding the bar in the direction of retaining legs of the L-shaped slots latches the tiles in place over the wall. Resilient contact strips under the parallel sides of the U-shaped tile assure thermal and electrical contact with the wall. 6 figs.
The Evolution of Biological Complexity in Digital Organisms
NASA Astrophysics Data System (ADS)
Ofria, Charles
2013-03-01
When Darwin first proposed his theory of evolution by natural selection, he realized that it had a problem explaining the origins of traits of ``extreme perfection and complication'' such as the vertebrate eye. Critics of Darwin's theory have latched onto this perceived flaw as a proof that Darwinian evolution is impossible. In anticipation of this issue, Darwin described the perfect data needed to understand this process, but lamented that such data are ``scarcely ever possible'' to obtain. In this talk, I will discuss research where we use populations of digital organisms (self-replicating and evolving computer programs) to elucidate the genetic and evolutionary processes by which new, highly-complex traits arise, drawing inspiration directly from Darwin's wistful thinking and hypotheses. During the process of evolution in these fully-transparent computational environments we can measure the incorporation of new information into the genome, a process akin to a natural Maxwell's Demon, and identify the original source of any such information. We show that, as Darwin predicted, much of the information used to encode a complex trait was already in the genome as part of simpler evolved traits, and that many routes must be possible for a new complex trait to have a high probability of successfully evolving. In even more extreme examples of the evolution of complexity, we are now using these same principles to examine the evolutionary dynamics the drive major transitions in evolution; that is transitions to higher-levels of organization, which are some of the most complex evolutionary events to occur in nature. Finally, I will explore some of the implications of this research to other aspects of evolutionary biology and as well as ways that these evolutionary principles can be applied toward solving computational and engineering problems.
Optimal positions for the release of primitive neonatal reflexes stimulating breastfeeding.
Colson, Suzanne D; Meek, Judith H; Hawdon, Jane M
2008-07-01
Despite widespread skills-teaching, 37% of UK mothers initiating breastfeeding stop by six weeks suggesting a need to reappraise current support strategies. Rooting, sucking and swallowing have been studied extensively but little is known about the role other primitive neonatal reflexes (PNRs) might play to support breastfeeding. To describe and compare PNRs observed during feeding, investigating whether certain feeding behaviours and positions, collectively termed Biological Nurturing, (BN) are associated with the release of those reflexes pivotal in establishing successful feeding. 40 breastfed healthy term mother/baby pairs were recruited using quota sampling to stratify term gestational age. Feeding sessions were videotaped in the first postnatal month, either in hospital or at home. 20 PNRs were validated and classified into 4 types (endogenous, motor, rhythmic and anti-gravity) and 2 functional clusters (finding/latching, milk transfer) either stimulating or hindering feeding. Significantly more PNRs were observed as stimulants in semi-reclined postures (BN) than when mothers were upright or side-lying (p=<0.0005). This study is the first to describe a range of semi-reclined maternal postures interacting with neonatal positions, releasing maternal instinctual behaviours and PNRs stimulating breastfeeding. Traditionally the human neonate has been considered a dorsal feeder with pressure needed along the baby's back. Compelling visual data here illustrate that the newborn is an abdominal feeder and, like some other animals, displays anti-gravity reflexes aiding latch. Findings suggest that breastfeeding initiation is innate for both mother and baby, not learned, thus challenging the routine skills-teaching currently central to breastfeeding support.
Puapornpong, Pawin; Raungrongmorakot, Kasem; Laosooksathit, Wipada; Hanprasertpong, Tharangrut; Ketsuwan, Sukwadee
2017-05-01
The breastfeeding position routinely used following a cesarean section is the side-lying position. However, there have been few studies about the effect of breastfeeding positions, including laid-back position on breastfeeding outcomes. To compare the breastfeeding outcomes between using laid-back and side-lying breastfeeding positions in mothers delivering by cesarean section. A randomized controlled trial was conducted. The postpartum mothers delivering by cesarean section who delivered term newborns were randomly assigned to learn the use of a laid-back or side-lying breastfeeding position. The breastfeeding outcomes were assessed by LATCH scores at the second day postpartum and exclusive breastfeeding rates during the 6-week postpartum period. The mother's satisfaction of each breastfeeding position was collected before discharge from the hospital. The data from 152 postpartum mothers delivering by cesarean section were available for analysis, 76 from the laid-back position group and 76 from side-lying position group. The baseline characteristics of both groups were similar. There were no statistically significant differences of the breastfeeding outcomes, LATCH scores at the second day postpartum and the exclusive breastfeeding rates during the 6-week postpartum period. But the mothers had expressed more satisfaction from the side-lying than the laid-back position. Among the mothers who delivered by cesarean section, the use of the laid-back breastfeeding position had not shown different breastfeeding outcomes from the side-lying breastfeeding position. It might be an alternative breastfeeding position, which can be taught for mothers delivering by cesarean section along with the side-lying position.
Feed-forward motor control of ultrafast, ballistic movements.
Kagaya, K; Patek, S N
2016-02-01
To circumvent the limits of muscle, ultrafast movements achieve high power through the use of springs and latches. The time scale of these movements is too short for control through typical neuromuscular mechanisms, thus ultrafast movements are either invariant or controlled prior to movement. We tested whether mantis shrimp (Stomatopoda: Neogonodactylus bredini) vary their ultrafast smashing strikes and, if so, how this control is achieved prior to movement. We collected high-speed images of strike mechanics and electromyograms of the extensor and flexor muscles that control spring compression and latch release. During spring compression, lateral extensor and flexor units were co-activated. The strike initiated several milliseconds after the flexor units ceased, suggesting that flexor activity prevents spring release and determines the timing of strike initiation. We used linear mixed models and Akaike's information criterion to serially evaluate multiple hypotheses for control mechanisms. We found that variation in spring compression and strike angular velocity were statistically explained by spike activity of the extensor muscle. The results show that mantis shrimp can generate kinematically variable strikes and that their kinematics can be changed through adjustments to motor activity prior to the movement, thus supporting an upstream, central-nervous-system-based control of ultrafast movement. Based on these and other findings, we present a shishiodoshi model that illustrates alternative models of control in biological ballistic systems. The discovery of feed-forward control in mantis shrimp sets the stage for the assessment of targets, strategic variation in kinematics and the role of learning in ultrafast animals. © 2016. Published by The Company of Biologists Ltd.
Head Excursion of Restrained Human Volunteers and Hybrid III Dummies in Steady State Rollover Tests
Moffatt, Edward; Hare, Barry; Hughes, Raymond; Lewis, Lance; Iiyama, Hiroshi; Curzon, Anne; Cooper, Eddie
2003-01-01
Seatbelts provide substantial benefits in rollover crashes, yet occupants still receive head and neck injuries from contacting the vehicle roof interior when the roof exterior strikes the ground. Prior research has evaluated rollover restraint performance utilizing anthropomorphic test devices (dummies), but little dynamic testing has been done with human volunteers to learn how they move during rollovers. In this study, the vertical excursion of the head of restrained dummies and human subjects was measured in a vehicle being rotated about its longitudinal roll axis at roll rates from 180-to-360 deg/sec and under static inversion conditions. The vehicle’s restraint design was the commonly used 3-point seatbelt with continuous loop webbing and a sliding latch plate. This paper presents an analysis of the observed occupant motion and provides a comparison of dummy and human motion under similar test conditions. Thirty-five tests (eighteen static and seventeen dynamic) were completed using two different sizes of dummies and human subjects in both near and far-side roll directions. The research indicates that far-side rollovers cause the restrained test subjects to have greater head excursion than near-side rollovers, and that static inversion testing underestimates head excursion for far-side occupants. Human vertical head excursion of up to 200 mm was found at a roll rate of 220 deg/sec. Humans exhibit greater variability in head excursion in comparison to dummies. Transfer of seatbelt webbing through the latch plate did not correlate directly with differences in head excursion. PMID:12941241
Flaherman, Valerie J; Gay, Barbara; Scott, Cheryl; Avins, Andrew; Lee, Kathryn A; Newman, Thomas B
2012-01-01
Breast pumping or hand expression may be recommended when newborns latch or suck poorly. A recent trial found worse outcomes among mothers who used a breast pump in the early postpartum period. The objective of this study was to compare bilateral electric breast pumping to hand expression among mothers of healthy term infants feeding poorly at 12-36 h after birth. Randomised controlled trial. Well-baby nursery and postpartum unit. 68 mothers of newborns 12-36 h old who were latching or sucking poorly were randomly assigned to either 15 min of bilateral electric pumping or 15 min of hand expression. Milk transfer, maternal pain, breastfeeding confidence and breast milk expression experience (BMEE) immediately after the intervention, and breastfeeding rates at 2 months after birth. The median volume of expressed milk (range) was 0.5 (0-5) ml for hand expressing mothers and 1 (0-40) ml for pumping mothers (p=0.07). Maternal pain, breastfeeding confidence and BMEE did not differ by intervention. At 2 months, mothers assigned to hand expression were more likely to be breastfeeding (96.1%) than mothers assigned to breast pumping (72.7%) (p=0.02). Hand expression in the early postpartum period appears to improve eventual breastfeeding rates at 2 months after birth compared with breast pumping, but further research is needed to confirm this. However, in circumstances where either pumping or hand expression would be appropriate for healthy term infants 12-36 h old feeding poorly, providers should consider recommending hand expression.
NASA Astrophysics Data System (ADS)
McNerney, Gregory Paul
Human immunodeficiency virus 1 (HIV-1) is a human retrovirus that efficiently, albeit gradually, overruns the immune system. An already infected T lymphocyte can latch onto another T lymphocyte whereby creating a virological synapse (VS); this junction drives viral assembly and transfer to the target cell in batches in an efficient, protective manor. My Ph.D. doctoral thesis focused on studying this transmission mechanism using advanced optical imaging modalities and the fully infectious fluorescent clone HIV Gag-iGFP. T lymphocytes are non-adherent cells (˜10 um thick) and the viral transmission process is fairly dynamic, hence we employed a custom spinning disk confocal microscope that revealed many interesting characteristics of this cooperative event. This methodology has low throughput as cell contact and transfer is at random. Optical tweezers was then added to the microscope to directly initiate cell contact at will. To assess when viral maturation occurs post-transfer, an optical assay based off of Forster resonance energy transfer was developed to monitor maturation. Structured illumination microscopy was further used to image the process at higher resolution and it showed that viral particles are not entering existing degradative compartments. Non-HIV-1 applications of the optical technologies are also reviewed.
STS-31 Hubble Space Telescope (HST) pre-deployment procedures aboard OV-103
1990-04-24
During STS-31, the Hubble Space Telescope (HST) grappled by the remote manipulator system (RMS) end effector is held in appendage deploy position above Discovery, Orbiter Vehicle (OV) 103. The solar array (SA) bistem cassette has been released from its latch fittings. The bistem spreader bars begin to unfurl the SA wing. The secondary deployment mechanism (SDM) handle is visible at the SA end. Stowed against either side of the HST System Support Module (SSM) forward shell are the high-gain antennae (HGA). Puerto Rico and the Dominican Republic are recognizable at the left of the frame.
Process characteristics and design methods for a 300 deg quad OP amp
NASA Technical Reports Server (NTRS)
Beasom, J. D.; Patterson, R. B., III
1981-01-01
The results of process characterization, circuit design, and reliability studies for the development of a quad OP amplifier intended for use up to 300 C are presented. A dielectrically isolated complementary vertical bipolar process was chosen to fabricate the amplifier in order to eliminate isolation leakage and the possibility of latch up. Characterization of NPN and PNP junctions showed them to be suitable for use up to 300 C. Interconnect reliability was predicted to be greater than four years mean time between failure. Parasitic MOS formation was eliminated by isolation of each device.
T-Cell Warriors—Equipped to Kill Cancer Cells | Center for Cancer Research
When the body recognizes tumor cells as foreign, a natural immune response arises to attack them. Unfortunately, tumors have ways to evade immune surveillance systems and antitumor responses are often too weak to defeat the disease. Rather than relying on the body’s natural response, scientists can now manipulate a patient’s own immune cells so that they latch on to tumor cells by recognizing specific proteins on their surface. A type of immune cell that has been explored for this purpose is the killer (cytotoxic) T cell, which eliminates cells infected by viruses, damaged cells, and tumor cells.
2017-03-24
iss050e059620 (03/24/2017) --- Expedition 50 Commander Shane Kimbrough of NASA is seen floating into the Quest airlock at the conclusion of a spacewalk. Kimbrough and Flight Engineer Thomas Pesquet of ESA (European Space Agency) conducted a six hour and 34 minute spacewalk on March 24, 2017. The two astronauts successfully disconnected cables and electrical connections on the Pressurized Mating Adapter-3 to prepare for its robotic move, lubricated the latching end effector on the Special Purpose Dexterous Manipulator “extension” for the Canadarm2 robotic arm, inspected a radiator valve and replaced cameras on the Japanese segment of the outpost.
2017-03-24
iss050e059613 (03/24/2017) --- Expedition 50 Commander Shane Kimbrough of NASA is seen floating into the Quest airlock at the conclusion of a spacewalk. Kimbrough and Flight Engineer Thomas Pesquet of ESA (European Space Agency) conducted a six hour and 34 minute spacewalk on March 24, 2017. The two astronauts successfully disconnected cables and electrical connections on the Pressurized Mating Adapter-3 to prepare for its robotic move, lubricated the latching end effector on the Special Purpose Dexterous Manipulator “extension” for the Canadarm2 robotic arm, inspected a radiator valve and replaced cameras on the Japanese segment of the outpost.
2017-03-24
iss050e059576 (03/24/2017) --- Russian cosmonaut Oleg Novitskiy (middle) poses with Expedition 50 Commander Shane Kimbrough of NASA (left) and Flight Engineer Thomas Pesquet of ESA (European Space Agency) (right) prior to their spacewalk. The pair conducted a six hour and 34 minute spacewalk on March 24, 2017. The two astronauts successfully disconnected cables and electrical connections on the Pressurized Mating Adapter-3 to prepare for its robotic move, lubricated the latching end effector on the Special Purpose Dexterous Manipulator “extension” for the Canadarm2 robotic arm, inspected a radiator valve and replaced cameras on the Japanese segment of the outpost.
2017-03-24
iss050e059529 (03/24/2017) --- Flight Engineer Thomas Pesquet of ESA (European Space Agency) is seen performing maintenance on the Dextre robot during a spacewalk. Pesquet and Expedition 50 Commander Shane Kimbrough of NASA conducted a six hour and 34 minute spacewalk on March 24, 2017. The two astronauts successfully disconnected cables and electrical connections on the Pressurized Mating Adapter-3 to prepare for its robotic move, lubricated the latching end effector on the Special Purpose Dexterous Manipulator “extension” for the Canadarm2 robotic arm, inspected a radiator valve and replaced cameras on the Japanese segment of the outpost.
2017-03-24
iss050e059608 (03/24/2017) --- NASA astronaut Peggy Whitson controls the robotic arm aboard the International Space Station during a spacewalk. Expedition 50 Commander Shane Kimbrough of NASA and Flight Engineer Thomas Pesquet of ESA (European Space Agency) conducted a six hour and 34 minute spacewalk on March 24, 2017. The two astronauts successfully disconnected cables and electrical connections on the Pressurized Mating Adapter-3 to prepare for its robotic move, lubricated the latching end effector on the Special Purpose Dexterous Manipulator “extension” for the Canadarm2 robotic arm, inspected a radiator valve and replaced cameras on the Japanese segment of the outpost.
2017-03-24
iss050e059579 (03/24/2017) --- NASA astronaut Peggy Whitson (middle) poses with Expedition 50 Commander Shane Kimbrough of NASA (left) and Flight Engineer Thomas Pesquet of ESA (European Space Agency) (right) prior to their spacewalk. The pair conducted a six hour and 34 minute spacewalk on March 24, 2017. The two astronauts successfully disconnected cables and electrical connections on the Pressurized Mating Adapter-3 to prepare for its robotic move, lubricated the latching end effector on the Special Purpose Dexterous Manipulator “extension” for the Canadarm2 robotic arm, inspected a radiator valve and replaced cameras on the Japanese segment of the outpost.
2017-03-24
iss050e059752 (03/24/2017) --- Flight Engineer Thomas Pesquet of ESA (European Space Agency) is seen floating outside the International Space Station during a spacewalk. Pesquet and Expedition 50 Commander Shane Kimbrough of NASA conducted a six hour and 34 minute spacewalk on March 24, 2017. The two astronauts successfully disconnected cables and electrical connections on the Pressurized Mating Adapter-3 to prepare for its robotic move, lubricated the latching end effector on the Special Purpose Dexterous Manipulator “extension” for the Canadarm2 robotic arm, inspected a radiator valve and replaced cameras on the Japanese segment of the outpost.