WorldWideScience

Sample records for heading lock maneuver

  1. How Lovebirds Maneuver Rapidly Using Super-Fast Head Saccades and Image Feature Stabilization.

    Directory of Open Access Journals (Sweden)

    Daniel Kress

    Full Text Available Diurnal flying animals such as birds depend primarily on vision to coordinate their flight path during goal-directed flight tasks. To extract the spatial structure of the surrounding environment, birds are thought to use retinal image motion (optical flow that is primarily induced by motion of their head. It is unclear what gaze behaviors birds perform to support visuomotor control during rapid maneuvering flight in which they continuously switch between flight modes. To analyze this, we measured the gaze behavior of rapidly turning lovebirds in a goal-directed task: take-off and fly away from a perch, turn on a dime, and fly back and land on the same perch. High-speed flight recordings revealed that rapidly turning lovebirds perform a remarkable stereotypical gaze behavior with peak saccadic head turns up to 2700 degrees per second, as fast as insects, enabled by fast neck muscles. In between saccades, gaze orientation is held constant. By comparing saccade and wingbeat phase, we find that these super-fast saccades are coordinated with the downstroke when the lateral visual field is occluded by the wings. Lovebirds thus maximize visual perception by overlying behaviors that impair vision, which helps coordinate maneuvers. Before the turn, lovebirds keep a high contrast edge in their visual midline. Similarly, before landing, the lovebirds stabilize the center of the perch in their visual midline. The perch on which the birds land swings, like a branch in the wind, and we find that retinal size of the perch is the most parsimonious visual cue to initiate landing. Our observations show that rapidly maneuvering birds use precisely timed stereotypic gaze behaviors consisting of rapid head turns and frontal feature stabilization, which facilitates optical flow based flight control. Similar gaze behaviors have been reported for visually navigating humans. This finding can inspire more effective vision-based autopilots for drones.

  2. Lock-in thermographic inspection of squats on rail steel head

    Science.gov (United States)

    Peng, D.; Jones, R.

    2013-03-01

    The development of squat defects has become a major concern in numerous railway systems throughout the world. Infrared thermography is a relatively new non-destructive inspection technique used for a wide range of applications. However, it has not been used for rail squat detection. Lock-in thermography is a non-destructive inspection technique that utilizes an infrared camera to detect the thermal waves. A thermal image is produced, which displays the local thermal wave variation in phase or amplitude. In inhomogeneous materials, the amplitude and phase of the thermal wave carries information related to both the local thermal properties and the nature of the structure being inspected. By examining the infrared thermal signature of squat damage on the head of steel rails, it was possible to generate a relationship matching squat depth to thermal image phase angle, using appropriate experimental/numerical calibration. The results showed that with the additional data sets obtained from further experimental tests, the clarity of this relationship will be greatly improved to a level whereby infrared thermal contours can be directly translated into the precise subsurface behaviour of a squat.

  3. Enhanced/synthetic vision and head-worn display technologies for terminal maneuvering area NextGen operations

    Science.gov (United States)

    Arthur, Jarvis J., III; Prinzel, Lawrence J., III; Williams, Steven P.; Bailey, Randall E.; Shelton, Kevin J.; Norman, R. Mike

    2011-06-01

    NASA is researching innovative technologies for the Next Generation Air Transportation System (NextGen) to provide a "Better-Than-Visual" (BTV) capability as adjunct to "Equivalent Visual Operations" (EVO); that is, airport throughputs equivalent to that normally achieved during Visual Flight Rules (VFR) operations rates with equivalent and better safety in all weather and visibility conditions including Instrument Meteorological Conditions (IMC). These new technologies build on proven flight deck systems and leverage synthetic and enhanced vision systems. Two piloted simulation studies were conducted to access the use of a Head-Worn Display (HWD) with head tracking for synthetic and enhanced vision systems concepts. The first experiment evaluated the use a HWD for equivalent visual operations to San Francisco International Airport (airport identifier: KSFO) compared to a visual concept and a head-down display concept. A second experiment evaluated symbology variations under different visibility conditions using a HWD during taxi operations at Chicago O'Hare airport (airport identifier: KORD). Two experiments were conducted, one in a simulated San Francisco airport (KSFO) approach operation and the other, in simulated Chicago O'Hare surface operations, evaluating enhanced/synthetic vision and head-worn display technologies for NextGen operations. While flying a closely-spaced parallel approach to KSFO, pilots rated the HWD, under low-visibility conditions, equivalent to the out-the-window condition, under unlimited visibility, in terms of situational awareness (SA) and mental workload compared to a head-down enhanced vision system. There were no differences between the 3 display concepts in terms of traffic spacing and distance and the pilot decision-making to land or go-around. For the KORD experiment, the visibility condition was not a factor in pilot's rating of clutter effects from symbology. Several concepts for enhanced implementations of an unlimited field

  4. Stability of radial head and neck fractures: a biomechanical study of six fixation constructs with consideration of three locking plates.

    Science.gov (United States)

    Burkhart, Klaus Josef; Mueller, Lars P; Krezdorn, David; Appelmann, Philipp; Prommersberger, Karl J; Sternstein, Werner; Rommens, Pol M

    2007-12-01

    Open reduction and internal fixation of radial neck fractures can lead to secondary loss of reduction and nonunion due to insufficient stability. Nevertheless, there are only a few biomechanical studies about the stability achieved by different osteosynthesis constructs. Forty-eight formalin-fixed, human proximal radii were divided into 6 groups according to their bone density (measured by dual-energy x-ray absorptiometry). A 2.7-mm gap osteotomy was performed to simulate an unstable radial neck fracture, which was fixed with 3 nonlocking implants: a 2.4-mm T plate, a 2.4-mm blade plate, and 2.0-mm crossed screws, and 3 locking plates: a 2.0-mm LCP T plate, a 2.0-mm 6x2 grid plate, and a 2.0-mm radial head plate. Implants were tested under axial (N/mm) and torsional (Ncm/ degrees ) loads with a servohydraulic materials testing machine. The radial head plate was significantly stiffer than all other implants under axial as well as under torsional loads, with values of 36 N/mm and 13 Ncm/ degrees . The second-stiffest implant was the blade plate, with values of 20 N/mm and 6 Ncm/ degrees . The weakest implants were the 2.0-mm LCP, with values of 6 N/mm and 2 Ncm/ degrees , and the 2.0-mm crossed screws, with values of 18 N/mm and 2 Ncm/ degrees . The 2.4-mm T plate, with values of 14 N/mm and 4 Ncm/ degrees , and the 2.0-mm grid plate, with values of 8 N/mm and 4 Ncm/ degrees came to lie in the midfield. The 2.0-mm angle-stable plates-depending on their design-allow fixation with comparable or even higher stability than the bulky 2.4-mm nonlocking implants and 2.0-mm crossed screws.

  5. Long-term outcome of segmental reconstruction of the humeral head for the treatment of locked posterior dislocation of the shoulder.

    Science.gov (United States)

    Gerber, Christian; Catanzaro, Sabrina; Jundt-Ecker, Michele; Farshad, Mazda

    2014-11-01

    Locked posterior glenohumeral dislocations with impaction fractures involving less than 30% to 35% of the humeral head are most frequently treated with lesser tuberosity transfer into the defect, whereas those involving more than 35% to 40% are treated with humeral head arthroplasty. As an alternative, reconstruction of the defect with segmental femoral or humeral head allograft has been proposed, but the long-term outcome of this joint-preserving procedure is unknown. Twenty-two shoulders in 21 patients with a locked posterior shoulder dislocation and an impaction of at least 30% (mean, 43%) of the humeral head were treated with segmental reconstruction of the humeral head defect. They were reviewed clinically and radiographically at a minimum follow-up of 5 years. Of the 22 shoulders, 19 could be followed up at 128 months (range, 60-294 months) postoperatively. Only 2 of the 19 patients needed a prosthesis more than 180 months after the index operation. Of the other 17, 4 had radiographically advanced osteoarthritis (OA), 4 had mild OA, and 9 had no or minimal OA. Eighteen shoulders were rated as subjectively excellent, none were rated as good, and one was rated as fair. The final Constant-Murley score averaged 77 points (range, 52-98 points), the Subjective Shoulder Value averaged 88% (range, 75%-100%), and only 2 patients had mild to moderate pain. Mean active anterior elevation was 145°, and mean external rotation with the arm at the side was 42°. Segmental reconstruction of humeral head defects for large anteromedial impaction fractures caused by locked posterior dislocations durably restores stability and freedom from pain with an excellent subjective long-term outcome. Copyright © 2014 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

  6. Orbital maneuvering end effectors

    Science.gov (United States)

    Myers, W. Neill (Inventor); Forbes, John C. (Inventor); Barnes, Wayne L. (Inventor)

    1986-01-01

    This invention relates to an end effector device for grasping and maneuvering objects such as berthing handles of a space telescope. The device includes a V-shaped capture window defined as inclined surfaces in parallel face plates which converge toward a retainer recess in which the handle is retained. A pivotal finger (30) meshes with a pair of pivoted fingers which rotate in counterrotation. The fingers rotate to pull a handle within the capture window into recess where latches lock handle in the recess. To align the capture window, plates may be cocked plus or minus five degrees on base. Drive means is included in the form of a motor coupled with a harmonic drive speed reducer, which provides for slow movement of the fingers at a high torque so that large articles may be handled. Novelty of the invention is believed to reside in the combined intermeshing finger structure, drive means and the harmonic drive speed reducer, which features provide the required maneuverability and strength.

  7. Neonatal morbidity associated with shoulder dystocia maneuvers.

    Science.gov (United States)

    Spain, Janine E; Frey, Heather A; Tuuli, Methodius G; Colvin, Ryan; Macones, George A; Cahill, Alison G

    2015-03-01

    We sought to examine neonatal morbidity associated with different maneuvers used among term patients who experience a shoulder dystocia. We conducted a retrospective cohort study of all women who experienced a clinically diagnosed shoulder dystocia at term requiring obstetric maneuvers at a single tertiary care hospital from 2005 through 2008. We excluded women with major fetal anomaly, intrauterine death, multiple gestation, and preterm. Women exposed to Rubin maneuver, Wood's screw maneuver, or delivery of the posterior arm were compared to women delivered by McRoberts/suprapubic pressure only, which served as the reference group. The primary outcome was a composite morbidity of neonatal injury (defined as clavicular or humeral fracture or brachial plexus injury) and neonatal depression (defined as Apgar dystocia, defined as time from delivery of fetal head to delivery of shoulders. Among the 231 women who met inclusion criteria, 135 were delivered by McRoberts/suprapubic pressure alone (57.9%), 83 women were exposed to Rubin maneuver, 53 women were exposed to Wood's screw, and 36 women were exposed to delivery of posterior arm. Individual maneuvers were not associated with composite morbidity, neonatal injury, or neonatal depression after adjusting for nulliparity and duration of shoulder dystocia. We found no association between shoulder dystocia maneuvers and neonatal morbidity after adjusting for duration, a surrogate for severity. Our results demonstrate that clinicians should utilize the maneuver most likely to result in successful delivery. Copyright © 2015 Elsevier Inc. All rights reserved.

  8. Locked Central Fracture Dislocation of the Hip in a Child after Low-Energy Trauma

    Directory of Open Access Journals (Sweden)

    Alexandre H. Nehme

    2017-01-01

    Full Text Available We present the case of a 13-year-old boy who sustained a locked central fracture dislocation of the right acetabulum following a bicycle fall. Immediate external reduction maneuvers under general anesthesia were unsuccessful due to intrapelvic entrapment of the femoral head. Open reduction internal fixation was achieved 48 hours later. After an initial satisfactory postoperative course, the patient ended up developing severe hip osteoarthritis 16 months after the procedure. The rarity of this injury in children is discussed, with its possible implications on joint congruity and potential growth injury.

  9. Maneuver Automation Software

    Science.gov (United States)

    Uffelman, Hal; Goodson, Troy; Pellegrin, Michael; Stavert, Lynn; Burk, Thomas; Beach, David; Signorelli, Joel; Jones, Jeremy; Hahn, Yungsun; Attiyah, Ahlam; hide

    2009-01-01

    The Maneuver Automation Software (MAS) automates the process of generating commands for maneuvers to keep the spacecraft of the Cassini-Huygens mission on a predetermined prime mission trajectory. Before MAS became available, a team of approximately 10 members had to work about two weeks to design, test, and implement each maneuver in a process that involved running many maneuver-related application programs and then serially handing off data products to other parts of the team. MAS enables a three-member team to design, test, and implement a maneuver in about one-half hour after Navigation has process-tracking data. MAS accepts more than 60 parameters and 22 files as input directly from users. MAS consists of Practical Extraction and Reporting Language (PERL) scripts that link, sequence, and execute the maneuver- related application programs: "Pushing a single button" on a graphical user interface causes MAS to run navigation programs that design a maneuver; programs that create sequences of commands to execute the maneuver on the spacecraft; and a program that generates predictions about maneuver performance and generates reports and other files that enable users to quickly review and verify the maneuver design. MAS can also generate presentation materials, initiate electronic command request forms, and archive all data products for future reference.

  10. É importante restringir a movimentação cefálica após a manobra de Epley? Is it important to restrict head movement after Epley maneuver?

    Directory of Open Access Journals (Sweden)

    Fernando Freitas Ganança

    2005-12-01

    head movements and to use a cervical collar and group 2 patients were not informed about these postmaneuver restrictions. The patients from both groups were reevaluated one week after Epley maneuver, regarding the presence of symptoms and positional nystagmus. RESULTS: One week after Epley maneuver 82.1% of the patients from group 1 and 73.3% from group 2 didn't present positional nystagmus (p=0.421. There was a clinical improvement in 96.0% of the patients from group 1 and in 94.0% from group 2 (p=0.781. CONCLUSION: The use of postural restrictions in patients with benign paroxysmal positional vertigo of posterior canal didn't interfere in their clinical evaluation, one week after a unique Epley maneuver.

  11. Automatic locking radioisotope camera lock

    International Nuclear Information System (INIS)

    Rosauer, P.J.

    1978-01-01

    The lock of the present invention secures the isotope source in a stored shielded condition in the camera until a positive effort has been made to open the lock and take the source outside of the camera and prevents disconnection of the source pigtail unless the source is locked in a shielded condition in the camera. It also gives a visual indication of the locked or possible exposed condition of the isotope source and prevents the source pigtail from being completely pushed out of the camera, even when the lock is released. (author)

  12. Robust tilt and lock mechanism for hopping actuator

    Energy Technology Data Exchange (ETDEWEB)

    Salton, Jonathan R.; Buerger, Stephen; Dullea, Kevin J.; Marron, Lisa C.; Salisbury, Curt Michael; Spletzer, Barry Louis

    2017-02-07

    A tilt and lock apparatus that includes a tilt servomechanism, a spiral torsion spring, a lock wheel, and a lock hook is described herein. The spiral torsion spring is mechanically coupled to the tilt servomechanism and the lock wheel (which includes an opening). When a shaft is positioned through the opening, rotation of the lock wheel is in unison with rotation of the shaft. An external surface of the lock wheel includes one or more grooves. The lock hook includes a head that engages and disengages the grooves. The lock wheel is stationary when the head engages one of the grooves and is rotatable when the head disengages the grooves. The head and the grooves are geometrically aligned when engaged to prevent creation of a force that acts to disengage the head responsive to an applied force acting on the shaft.

  13. Air lock

    International Nuclear Information System (INIS)

    Palkovich, P.; Gruber, J.; Madlener, W.

    1974-01-01

    The patent refers to an air lock system preferably for nuclear stations for the transport of heavy loads by means of a trolley on rails. For opening and closing of the air lock parts of the rails are removed, e.g. by a second rail system perpendicular to the main rails. (P.K.)

  14. Maneuver from the Air Domain

    Science.gov (United States)

    2016-05-26

    Overload From the previous discussion, cognitive maneuver seeks to degrade the enemy’s capacity for...in all domains, the ability to maneuver from the air domain in the cognitive sense, comes primarily from air power’s unique ability to overload the... cognitive maneuver mechanisms developed in the 1980s as part of broader maneuver warfare theory. The result is a proposed definition of maneuver from

  15. Qualitative analysis of the Dix-Hallpike maneuver in multi-canal BPPV using a biomechanical model: Introduction of an expanded Dix-Hallpike maneuver for enhanced diagnosis of multi-canal BPPV

    Directory of Open Access Journals (Sweden)

    Henri Traboulsi

    2017-09-01

    Conclusion: The Dix–Hallpike maneuver may cause simultaneous movement of otoliths present in multiple canals and create an obstacle to accurate diagnosis in multi-canal BPPV. An expanded Dix-Hallpike maneuver is described which adds intermediate steps with the head positioned to the right and left in the horizontal position before head-hanging. This expanded maneuver has helped to isolate affected semi-circular canals for individual assessment in multiple canal BPPV.

  16. THE DUBINS TRAVELING SALESMAN PROBLEM WITH CONSTRAINED COLLECTING MANEUVERS

    Directory of Open Access Journals (Sweden)

    Petr Váňa

    2016-11-01

    Full Text Available In this paper, we introduce a variant of the Dubins traveling salesman problem (DTSP that is called the Dubins traveling salesman problem with constrained collecting maneuvers (DTSP-CM. In contrast to the ordinary formulation of the DTSP, in the proposed DTSP-CM, the vehicle is requested to visit each target by specified collecting maneuver to accomplish the mission. The proposed problem formulation is motivated by scenarios with unmanned aerial vehicles where particular maneuvers are necessary for accomplishing the mission, such as object dropping or data collection with sensor sensitive to changes in vehicle heading. We consider existing methods for the DTSP and propose its modifications to use these methods to address a variant of the introduced DTSP-CM, where the collecting maneuvers are constrained to straight line segments.

  17. Exploring precrash maneuvers using classification trees and random forests.

    Science.gov (United States)

    Harb, Rami; Yan, Xuedong; Radwan, Essam; Su, Xiaogang

    2009-01-01

    Taking evasive actions vis-à-vis critical traffic situations impending to motor vehicle crashes endows drivers an opportunity to avoid the crash occurrence or at least diminish its severity. This study explores the drivers, vehicles, and environments' characteristics associated with crash avoidance maneuvers (i.e., evasive actions or no evasive actions). Rear-end collisions, head-on collisions, and angle collisions are analyzed separately using decision trees and the significance of the variables on the binary response variable (evasive actions or no evasive actions) is determined. Moreover, the random forests method is employed to rank the importance of the drivers/vehicles/environments characteristics on crash avoidance maneuvers. According to the exploratory analyses' results, drivers' visibility obstruction, drivers' physical impairment, drivers' distraction are associated with crash avoidance maneuvers in all three types of accidents. Moreover, speed limit is associated with rear-end collisions' avoidance maneuvers and vehicle type is correlated with head-on collisions and angle collisions' avoidance maneuvers. It is recommended that future research investigates further the explored trends (e.g., physically impaired drivers, visibility obstruction) using driving simulators which may help in legislative initiatives and in-vehicle technology recommendations.

  18. Support and maneuvering device

    Science.gov (United States)

    Wood, R.L.

    1987-03-23

    A support and maneuvering device includes an elongated flexible inflatable enclosure having a fixed end and a movable end. The movable end is collapsible toward the fixed end to a contracted position when the enclosure is in a noninflated condition. Upon inflation, the movable end is movable away from the fixed end to an extended position. The movable end includes means for mounting an article such as a solar reflector thereon. The device also includes a plurality of position controlling means disposed about the movable end to effect adjusting movement of portions thereof by predetermined amounts and for controlling an angle at which the article disposed at the movable end is oriented. The plurality of position controlling means limits a suitable number degrees of freedom of the movable end for transmitting a steering motion thereto and for controlling the position thereof. 9 figs.

  19. The Advanced Thread-Locking Mechanism

    Science.gov (United States)

    Weiss, Wolfgang

    2005-12-01

    Locking of threaded members is accomplished by a wide variety of engineering solutions. Generally, in terms of separate locking devices or by built-in locking features such as friction generating means.In regard of space flight vehicles, threaded joints are subject to severe vibration loads during launch, maneuvering, and reentry. This requires fastening systems which are capable to join structural members and attach accessories or equipment in a secure manner. However, manned spacecraft and especially payload components will be subject to installation activity during orbital or interstellar flight maintenance, repair, or mission modification. This, in turn, requires fast separation and engaging of the concerned fasteners, yet providing performance characteristics for high reliable and safe joints.The further described Advanced Thread Locking Mechanism (ATLM) has been developed to combine the merits of both, safe joining technique and a fast installation process. The ATLM uses a freewheel which is securely installed in one part of the threaded member and releasable coupled with the engaged counterpart. While screwing the threaded members together, once coupled, the freewheel will allow free mating of the threaded members including torquing to the desired value. The moment, the pair of threaded fasteners is forced to unscrew (by intended or unintended occurrence of torque in the undoing direction) the freewheel does lock instantly. Disengaging the coupling between the members of the threaded joint takes a separate release action.Owing to the nature of the ATLM, there are a number of design variants ready for implementation.Threaded fasteners in ATLM design are highly recommended for mechanical joints subject to fastening and unfastening during Extra Vehicular Activity (EVA) in course of space flight operations. This is justified through:1. Threaded members mate free running, thus, torque values preset at the wrenching tool are not influenced by varying prevailing

  20. Investigation of piloting aids for manual control of hypersonic maneuvers

    Science.gov (United States)

    Raney, David L.; Phillips, Michael R.; Person, Lee H., Jr.

    1995-01-01

    An investigation of piloting aids designed to provide precise maneuver control for an air-breathing hypersonic vehicle is described. Stringent constraints and nonintuitive high-speed flight effects associated with maneuvering in the hypersonic regime raise the question of whether manual control of such a vehicle should even be considered. The objectives of this research were to determine the extent of manual control that is desirable for a vehicle maneuvering in this regime and to identify the form of aids that must be supplied to the pilot to make such control feasible. A piloted real-time motion-based simulation of a hypersonic vehicle concept was used for this study, and the investigation focused on a single representative cruise turn maneuver. Piloting aids, which consisted of an auto throttle, throttle director, autopilot, flight director, and two head-up display configurations, were developed and evaluated. Two longitudinal control response types consisting of a rate-command/attitude-hold system and a load factor-rate/load-factor-hold system were also compared. The complete set of piloting aids, which consisted of the autothrottle, throttle director, and flight director, improved the average Cooper-Harper flying qualities ratings from 8 to 2.6, even though identical inner-loop stability and control augmentation was provided in all cases. The flight director was determined to be the most critical of these aids, and the cruise turn maneuver was unachievable to adequate performance specifications in the absence of this flight director.

  1. Locking of metacarpophalangeal joints in a patient with acromegaly

    Energy Technology Data Exchange (ETDEWEB)

    Tani, Y.; Tanaka, N.; Isoya, Eiji [Dept. of Orthopaedic Surgery, Soseikai General Hospital, Kyoto (Japan)

    1999-11-01

    A 39-year-old man with acromegaly exhibited locking of metacarpophalangeal (MCP) joints of both index fingers. Large osteophytes were found at the metacarpal heads by radiography and computerized tomography (CT). Magnetic resonance (MR) images revealed hypertrophy of volar plates. We suggest that these characteristic acromegalic features caused locking of MCP joints. Surgery was required on one of the joints to release the locking. (orig.)

  2. Locking of metacarpophalangeal joints in a patient with acromegaly

    International Nuclear Information System (INIS)

    Tani, Y.; Tanaka, N.; Isoya, Eiji

    1999-01-01

    A 39-year-old man with acromegaly exhibited locking of metacarpophalangeal (MCP) joints of both index fingers. Large osteophytes were found at the metacarpal heads by radiography and computerized tomography (CT). Magnetic resonance (MR) images revealed hypertrophy of volar plates. We suggest that these characteristic acromegalic features caused locking of MCP joints. Surgery was required on one of the joints to release the locking. (orig.)

  3. Locking plate fixation for proximal humerus fractures.

    LENUS (Irish Health Repository)

    Burke, Neil G

    2012-02-01

    Locking plates are increasingly used to surgically treat proximal humerus fractures. Knowledge of the bone quality of the proximal humerus is important. Studies have shown the medial and dorsal aspects of the proximal humeral head to have the highest bone strength, and this should be exploited by fixation techniques, particularly in elderly patients with osteoporosis. The goals of surgery for proximal humeral fractures should involve minimal soft tissue dissection and achieve anatomic reduction of the head complex with sufficient stability to allow for early shoulder mobilization. This article reviews various treatment options, in particular locking plate fixation. Locking plate fixation is associated with a high complication rate, such as avascular necrosis (7.9%), screw cutout (11.6%), and revision surgery (13.7%). These complications are frequently due to the varus deformation of the humeral head. Strategic screw placement in the humeral head would minimize the possibility of loss of fracture reduction and potential hardware complications. Locking plate fixation is a good surgical option for the management of proximal humerus fractures. Complications can be avoided by using better bone stock and by careful screw placement in the humeral head.

  4. Improved Maneuver Criteria Evaluation Program

    Science.gov (United States)

    1979-11-01

    If the rotor rpm breakpoint (OMGBL2) is le :-s than the mininum rotor rpm (OMEGMN), then the rpm bleed :ate (OMGBDI) will be the only bleed rate used...VCP =60 PSU 1 EEF = 1 OMGBD1=2 OMGBD3=0 OMGRC2=0 VERR = 2 MPRINT= 1 OMEGMN=300 OMGBL.2=4 OMGBL4=0 OMGRD2=0 MUF = 1 BINERT:2860 TRPMMN= 0 OMGBD2=0 OMGBD4...height is within 2 feet of the measured height. These comparisons show that the MCEP maneuvers are accurate for simulating these types of maneuvers

  5. Tool for cutting locking cups from guide tube mounting screws in a nuclear reactor

    International Nuclear Information System (INIS)

    Nee, J.D.; Hahn, J.J.

    1987-01-01

    This patent describes an apparatus for freeing a socket-head screw from a locking cup therefor in a reactor cavity, wherein the locking cup includes a fixed cylindrical side wall encircling the side surface of the screw head and an annular end wall overlying the outer end surface of the screw head. The apparatus consists of: frame means, cylindrical cutter means having a longitudinal axis and having a frustoconical cutting surface with an inner diameter less than the inner diameter of the locking cup side wall and with an outer diameter greater than the outer diameter of the locking cup side wall, and drive means carried by the frame means and coupled to the cutter means for effecting rotation thereof about the axis, the rotating cutter means are operable for severing the locking cup end wall from the locking cup side wall at the junction therebetween when the cutter means is moved against the locking cup substantially coaxially therewith

  6. Rendezvous maneuvers using Genetic Algorithm

    International Nuclear Information System (INIS)

    Dos Santos, Denílson Paulo Souza; De Almeida Prado, Antônio F Bertachini; Teodoro, Anderson Rodrigo Barretto

    2013-01-01

    The present paper has the goal of studying orbital maneuvers of Rendezvous, that is an orbital transfer where a spacecraft has to change its orbit to meet with another spacecraft that is travelling in another orbit. This transfer will be accomplished by using a multi-impulsive control. A genetic algorithm is used to find the transfers that have minimum fuel consumption

  7. 33 CFR 84.23 - Maneuvering light.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Maneuvering light. 84.23 Section... RULES ANNEX I: POSITIONING AND TECHNICAL DETAILS OF LIGHTS AND SHAPES § 84.23 Maneuvering light. Notwithstanding the provisions of § 84.03(f), the maneuvering light described in Rule 34(b) shall be placed...

  8. Correlation between crash avoidance maneuvers and injury severity sustained by motorcyclists in single-vehicle crashes.

    Science.gov (United States)

    Wang, Chen; Lu, Linjun; Lu, Jian; Wang, Tao

    2016-01-01

    In order to improve motorcycle safety, this article examines the correlation between crash avoidance maneuvers and injury severity sustained by motorcyclists, under multiple precrash conditions. Ten-year crash data for single-vehicle motorcycle crashes from the General Estimates Systems (GES) were analyzed, using partial proportional odds models (i.e., generalized ordered logit models). The modeling results show that "braking (no lock-up)" is associated with a higher probability of increased severity, whereas "braking (lock-up)" is associated with a higher probability of decreased severity, under all precrash conditions. "Steering" is associated with a higher probability of reduced injury severity when other vehicles are encroaching, whereas it is correlated with high injury severity under other conditions. "Braking and steering" is significantly associated with a higher probability of low severity under "animal encounter and object presence," whereas it is surprisingly correlated with high injury severity when motorcycles are traveling off the edge of the road. The results also show that a large number of motorcyclists did not perform any crash avoidance maneuvers or conducted crash avoidance maneuvers that are significantly associated with high injury severity. In general, this study suggests that precrash maneuvers are an important factor associated with motorcyclists' injury severity. To improve motorcycle safety, training/educational programs should be considered to improve safety awareness and adjust driving habits of motorcyclists. Antilock brakes and such systems are also promising, because they could effectively prevent brake lock-up and assist motorcyclists in maneuvering during critical conditions. This study also provides valuable information for the design of motorcycle training curriculum.

  9. Intelligent Prediction of Ship Maneuvering

    Directory of Open Access Journals (Sweden)

    Miroslaw Lacki

    2016-09-01

    Full Text Available In this paper the author presents an idea of the intelligent ship maneuvering prediction system with the usage of neuroevolution. This may be also be seen as the ship handling system that simulates a learning process of an autonomous control unit, created with artificial neural network. The control unit observes input signals and calculates the values of required parameters of the vessel maneuvering in confined waters. In neuroevolution such units are treated as individuals in population of artificial neural networks, which through environmental sensing and evolutionary algorithms learn to perform given task efficiently. The main task of the system is to learn continuously and predict the values of a navigational parameters of the vessel after certain amount of time, regarding an influence of its environment. The result of a prediction may occur as a warning to navigator to aware him about incoming threat.

  10. Protective air lock

    International Nuclear Information System (INIS)

    Evans, H.W.

    1976-01-01

    A device suitable for preventing escape and subsequent circulation of toxic gases is described. An enclosure is sealed by a surrounding air lock, and an automatic mechanism partially evacuates the enclosure and air lock. The enclosure ventilating mechanism can be disconnected so that a relatively undisturbed atmosphere is created in the enclosure

  11. Bicycle Parking and Locking

    DEFF Research Database (Denmark)

    Larsen, Jonas

    2017-01-01

    . This article contributes with new insights into parking and locking - ‘moorings’ - to cycling literature. It presents an ethnography of ‘design moorings’ and practices associated with parking and locking bikes. The main case study is the very pro-cycling city of Copenhagen. Yet to explore what is unique about...

  12. Cassini-Huygens maneuver automation for navigation

    Science.gov (United States)

    Goodson, Troy; Attiyah, Amy; Buffington, Brent; Hahn, Yungsun; Pojman, Joan; Stavert, Bob; Strange, Nathan; Stumpf, Paul; Wagner, Sean; Wolff, Peter; hide

    2006-01-01

    Many times during the Cassini-Huygens mission to Saturn, propulsive maneuvers must be spaced so closely together that there isn't enough time or workforce to execute the maneuver-related software manually, one subsystem at a time. Automation is required. Automating the maneuver design process has involved close cooperation between teams. We present the contribution from the Navigation system. In scope, this includes trajectory propagation and search, generation of ephemerides, general tasks such as email notification and file transfer, and presentation materials. The software has been used to help understand maneuver optimization results, Huygens probe delivery statistics, and Saturn ring-plane crossing geometry. The Maneuver Automation Software (MAS), developed for the Cassini-Huygens program enables frequent maneuvers by handling mundane tasks such as creation of deliverable files, file delivery, generation and transmission of email announcements, generation of presentation material and other supporting documentation. By hand, these tasks took up hours, if not days, of work for each maneuver. Automated, these tasks may be completed in under an hour. During the cruise trajectory the spacing of maneuvers was such that development of a maneuver design could span about a month, involving several other processes in addition to that described, above. Often, about the last five days of this process covered the generation of a final design using an updated orbit-determination estimate. To support the tour trajectory, the orbit determination data cut-off of five days before the maneuver needed to be reduced to approximately one day and the whole maneuver development process needed to be reduced to less than a week..

  13. ''Old'' locked inflation

    International Nuclear Information System (INIS)

    Liu, Yang; Piao, Yun-Song; Si, Zong-Guo

    2009-01-01

    In this paper, we revisit the idea of locked inflation, which does not require a potential satisfying the normal slow-roll condition, but suffers from the problems associated with ''saddle inflation''. We propose a scenario based on locked inflation, however, with an alternative evolution mechanism of the ''waterfall field'' φ. Instead of rolling down along the potential, the φ field will tunnel to end the inflation stage like in old inflation, by which the saddle inflation could be avoided. Further, we study a cascade of old locked inflation, which can be motivated by the string landscape. Our model is based on the consideration of making locked inflation feasible so as to give a working model without slow roll; It also can be seen as an effort to embed the old inflation in string landscape

  14. Quantum noise locking

    International Nuclear Information System (INIS)

    McKenzie, Kirk; Mikhailov, Eugeniy E; Goda, Keisuke; Lam, Ping Koy; Grosse, Nicolai; Gray, Malcolm B; Mavalvala, Nergis; McClelland, David E

    2005-01-01

    Quantum optical states which have no coherent amplitude, such as squeezed vacuum states, cannot rely on standard readout techniques to generate error signals for control of the quadrature phase. Here we investigate the use of asymmetry in the quadrature variances to obtain a phase-sensitive readout and to lock the phase of a squeezed vacuum state, a technique which we call noise locking (NL). We carry out a theoretical derivation of the NL error signal and the associated stability of the squeezed and anti-squeezed lock points. Experimental data for the NL technique both in the presence and absence of coherent fields are shown, including a comparison with coherent locking techniques. Finally, we use NL to enable a stable readout of the squeezed vacuum state on a homodyne detector

  15. LOCKS AND KEYS SERVICE

    CERN Multimedia

    Locks and Keys Service

    2002-01-01

    The Locks and Keys service (ST/FM) will move from building 55 to building 570 from the 2nd August to the 9th August 2002 included. During this period the service will be closed. Only in case of extreme urgency please call the 164550. Starting from Monday, 12th August, the Locks and Keys Service will continue to follow the activities related to office keys (keys and locks) and will provide the keys for furniture. The service is open from 8h30 to 12h00 and from 13h00 to 17h30. We remind you that your divisional correspondents can help you in the execution of the procedures. We thank you for your comprehension and we remain at your service to help you in solving all the matters related to keys for offices and furniture. Locks and Keys Service - ST Division - FM Group

  16. Locke and botany.

    Science.gov (United States)

    Anstey, Peter R; Harris, Stephen A

    2006-06-01

    This paper argues that the English philosopher John Locke, who has normally been thought to have had only an amateurish interest in botany, was far more involved in the botanical science of his day than has previously been known. Through the presentation of new evidence deriving from Locke's own herbarium, his manuscript notes, journal and correspondence, it is established that Locke made a modest contribution to early modern botany. It is shown that Locke had close and ongoing relations with the Bobarts, keepers of the Oxford Botanic Garden, and that Locke distributed seeds and plant parts to other botanists, seeds of which the progeny almost certainly ended up in the most important herbaria of the period. Furthermore, it is claimed that the depth of Locke's interest in and practice of botany has a direct bearing on our understanding of his views on the correct method of natural philosophy and on the interpretation of his well known discussion of the nature of species in Book III of his Essay concerning human understanding.

  17. The influence of airway supporting maneuvers on glottis view in pediatric fiberoptic bronchoscopy

    Directory of Open Access Journals (Sweden)

    Tarik Umutoglu

    2015-10-01

    Full Text Available ABSTRACTINTRODUCTION:Flexible fiber optic bronchoscopy is a valuable intervention for evaluation and management of respiratory diseases in both infants, pediatric and adult patients. The aim of this study is to investigate the influence of the airway supporting maneuvers on glottis view during pediatric flexible fiberoptic bronchoscopy.MATERIALS AND METHODS:In this randomized, controlled, crossover study; patients aged between 0 and 15 years who underwent flexible fiberoptic bronchoscopy procedure having American Society of Anesthesiologists I---II risk score were included. Patients having risk of difficult intubation, intubated or patients with tracheostomy, and patients with reduced neck mobility or having cautions for neck mobility were excluded from this study. After obtaining best glottic view at the neutral position, patients were positioned jaw trust with open mouth, jaw trust with teeth prottution, head tilt chin lift and triple airway maneuvers and best glottis scores were recorded.RESULTS:Total of 121 pediatric patients, 57 girls and 64 boys, were included in this study. Both jaw trust with open mouth and jaw trust with teeth prottution maneuvers improved the glottis view compared with neutral position (p 0.05. Head tilt chin lift and triple airway maneuvers improved glottis view when compared with both jaw trust with open mouth and jaw trust with teeth prottution maneuvers and neutral position (p 0.05.

  18. 46 CFR 109.564 - Maneuvering characteristics.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Maneuvering characteristics. 109.564 Section 109.564 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS OPERATIONS Miscellaneous § 109.564 Maneuvering characteristics. (a) The master or person in charge of each...

  19. Prevention of shoulder dystocia: A randomized controlled trial to evaluate an obstetric maneuver.

    Science.gov (United States)

    Poujade, Olivier; Azria, Elie; Ceccaldi, Pierre-François; Davitian, Carine; Khater, Carine; Chatel, Paul; Pernin, Emilie; Aflak, Nizar; Koskas, Martin; Bourgeois-Moine, Agnès; Hamou-Plotkine, Laurence; Valentin, Morgane; Renner, Jean-Paul; Roy, Carine; Estellat, Candice; Luton, Dominique

    2018-08-01

    Shoulder dystocia is a major obstetric emergency defined as a failure of delivery of the fetal shoulder(s). This study evaluated whether an obstetric maneuver, the push back maneuver performed gently on the fetal head during delivery, could reduce the risk of shoulder dystocia. We performed a multicenter, randomized, single-blind trial to compare the push back maneuver with usual care in parturient women at term. The primary outcome, shoulder dystocia, was considered to have occurred if, after delivery of the fetal head, any additional obstetric maneuver, beginning with the McRoberts maneuver, other than gentle downward traction and episiotomy was required. We randomly assigned 522 women to the push back maneuver group (group P) and 523 women to the standard vaginal delivery group (group S). Finally, 473 women assigned to group P and 472 women assigned to group S delivered vaginally. The rate of shoulder dystocia was significantly lower in group P (1·5%) than in group S (3·8%) (odds ratio [OR] 0·38 [0·16-0·92]; P = 0·03). After adjustment for predefined main risk factors, dystocia remained significantly lower in group P than in group S. There were no significant between-group differences in neonatal complications, including brachial plexus injury, clavicle fracture, hematoma and generalized asphyxia. In this trial in 945 women who delivered vaginally, the push back maneuver significantly decreased the risk of shoulder dystocia, as compared with standard vaginal delivery. Copyright © 2018 Elsevier B.V. All rights reserved.

  20. Flight Test Maneuvers for Efficient Aerodynamic Modeling

    Science.gov (United States)

    Morelli, Eugene A.

    2011-01-01

    Novel flight test maneuvers for efficient aerodynamic modeling were developed and demonstrated in flight. Orthogonal optimized multi-sine inputs were applied to aircraft control surfaces to excite aircraft dynamic response in all six degrees of freedom simultaneously while keeping the aircraft close to chosen reference flight conditions. Each maneuver was designed for a specific modeling task that cannot be adequately or efficiently accomplished using conventional flight test maneuvers. All of the new maneuvers were first described and explained, then demonstrated on a subscale jet transport aircraft in flight. Real-time and post-flight modeling results obtained using equation-error parameter estimation in the frequency domain were used to show the effectiveness and efficiency of the new maneuvers, as well as the quality of the aerodynamic models that can be identified from the resultant flight data.

  1. Experimental visualization of rapid maneuvering fish

    Science.gov (United States)

    Daigh, S.; Techet, A. H.

    2003-11-01

    A freshwater tropical fish, Danio aequippinatus, is studied undergoing rapid turning and fast starting maneuvers. This agile species of fish is ideal for this study as it is capable of quick turning and darting motions up to 5g's. The fgish studied are 4-5 cm in length. The speed and kinematics of the maneuvering is determined by video analysis. Planar and stereo Particle Image Velocimetry (PIV) is used to map the vortical patterns in the wake of the maneuvering fish. PIV visualizations reveal that during C-shaped maneuvers a ring shaped jet vortex is formed. Fast starting behavior is also presented. PIV data is used to approixmate the thrust vectoring force produced during each maneuver.

  2. In-shoe plantar tri-axial stress profiles during maximum-effort cutting maneuvers.

    Science.gov (United States)

    Cong, Yan; Lam, Wing Kai; Cheung, Jason Tak-Man; Zhang, Ming

    2014-12-18

    Soft tissue injuries, such as anterior cruciate ligament rupture, ankle sprain and foot skin problems, frequently occur during cutting maneuvers. These injuries are often regarded as associated with abnormal joint torque and interfacial friction caused by excessive external and in-shoe shear forces. This study simultaneously investigated the dynamic in-shoe localized plantar pressure and shear stress during lateral shuffling and 45° sidestep cutting maneuvers. Tri-axial force transducers were affixed at the first and second metatarsal heads, lateral forefoot, and heel regions in the midsole of a basketball shoe. Seventeen basketball players executed both cutting maneuvers with maximum efforts. Lateral shuffling cutting had a larger mediolateral braking force than 45° sidestep cutting. This large braking force was concentrated at the first metatarsal head, as indicated by its maximum medial shear stress (312.2 ± 157.0 kPa). During propulsion phase, peak shear stress occurred at the second metatarsal head (271.3 ± 124.3 kPa). Compared with lateral shuffling cutting, 45° sidestep cutting produced larger peak propulsion shear stress (463.0 ± 272.6 kPa) but smaller peak braking shear stress (184.8 ± 181.7 kPa), of which both were found at the first metatarsal head. During both cutting maneuvers, maximum medial and posterior shear stress occurred at the first metatarsal head, whereas maximum pressure occurred at the second metatarsal head. The first and second metatarsal heads sustained relatively high pressure and shear stress and were expected to be susceptible to plantar tissue discomfort or injury. Due to different stress distribution, distinct pressure and shear cushioning mechanisms in basketball footwear might be considered over different foot regions. Copyright © 2014 Elsevier Ltd. All rights reserved.

  3. Pressure locking test results

    Energy Technology Data Exchange (ETDEWEB)

    DeWall, K.G.; Watkins, J.C.; McKellar, M.G.; Bramwell, D. [Idaho National Engineering Lab., Idaho Falls, ID (United States)] [and others

    1996-12-01

    The U.S. Nuclear Regulatory Commission (NRC), Office of Nuclear Regulatory Research, is funding the Idaho National Engineering Laboratory (INEL) in performing research to provide technical input for their use in evaluating responses to Generic Letter 95-07, {open_quotes}Pressure Locking and Thermal Binding of Safety-Related Power-Operated Gate Valves.{close_quotes} Pressure locking and thermal binding are phenomena that make a closed gate valve difficult to open. This paper discusses only the pressure locking phenomenon in a flexible-wedge gate valve; the authors will publish the results of their thermal binding research at a later date. Pressure locking can occur when operating sequences or temperature changes cause the pressure of the fluid in the bonnet (and, in most valves, between the discs) to be higher than the pressure on the upstream and downstream sides of the disc assembly. This high fluid pressure presses the discs against both seats, making the disc assembly harder to unseat than anticipated by the typical design calculations, which generally consider friction at only one of the two disc/seat interfaces. The high pressure of the bonnet fluid also changes the pressure distribution around the disc in a way that can further contribute to the unseating load. If the combined loads associated with pressure locking are very high, the actuator might not have the capacity to open the valve. The results of the NRC/INEL research discussed in this paper show that the relationship between bonnet pressure and pressure locking stem loads appears linear. The results also show that for this valve, seat leakage affects the bonnet pressurization rate when the valve is subjected to thermally induced pressure locking conditions.

  4. Pressure locking test results

    International Nuclear Information System (INIS)

    DeWall, K.G.; Watkins, J.C.; McKellar, M.G.; Bramwell, D.

    1996-01-01

    The U.S. Nuclear Regulatory Commission (NRC), Office of Nuclear Regulatory Research, is funding the Idaho National Engineering Laboratory (INEL) in performing research to provide technical input for their use in evaluating responses to Generic Letter 95-07, open-quotes Pressure Locking and Thermal Binding of Safety-Related Power-Operated Gate Valves.close quotes Pressure locking and thermal binding are phenomena that make a closed gate valve difficult to open. This paper discusses only the pressure locking phenomenon in a flexible-wedge gate valve; we will publish the results of our thermal binding research at a later date. Pressure locking can occur when operating sequences or temperature changes cause the pressure of the fluid in the bonnet (and, in most valves, between the discs) to be higher than the pressure on the upstream and downstream sides of the disc assembly. This high fluid pressure presses the discs against both seats, making the disc assembly harder to unseat than anticipated by the typical design calculations, which generally consider friction at only one of the two disc/seat interfaces. The high pressure of the bonnet fluid also changes the pressure distribution around the disc in a way that can further contribute to the unseating load. If the combined loads associated with pressure locking are very high, the actuator might not have the capacity to open the valve. The results of the NRC/INEL research discussed in this paper show that the relationship between bonnet pressure and pressure locking stem loads appears linear. The results also show that for this valve, seat leakage affects the bonnet pressurization rate when the valve is subjected to thermally induced pressure locking conditions

  5. Orbital maneuvering vehicle end effectors

    Science.gov (United States)

    Myers, W. Neill (Inventor); Forbes, John C. (Inventor); Barnes, Wayne L. (Inventor)

    1988-01-01

    An end effector device (A) for grasping and holding an article such as a handle (18) of a space telescope is disclosed. The device includes a V-shaped capture window (74) defined as inclined surfaces (76, 78) in parallel face plates (22, 24) which converge toward a retainer recess (54) in which the handle is retained. A pivotal finger (30) meshes with a pair of pivoted fingers (26, 28) which rotate in counterrotation. The fingers rotate to pull a handle within the capture window into recess (54) where latches (50) lock handle (18) in the recess. To align the capture window, plates (22, 24) may be cocked plus or minus five degrees on base (64).

  6. Canadarm2 Maneuvers Quest Airlock

    Science.gov (United States)

    2001-01-01

    At the control of Expedition Two Flight Engineer Susan B. Helms, the newly-installed Canadian-built Canadarm2, Space Station Remote Manipulator System (SSRMS) maneuvers the Quest Airlock into the proper position to be mated onto the starboard side of the Unity Node I during the first of three extravehicular activities (EVA) of the STS-104 mission. The Quest Airlock makes it easier to perform space walks, and allows both Russian and American spacesuits to be worn when the Shuttle is not docked with the International Space Station (ISS). American suits will not fit through Russion airlocks at the Station. The Boeing Company, the space station prime contractor, built the 6.5-ton (5.8 metric ton) airlock and several other key components at the Marshall Space Flight Center (MSFC), in the same building where the Saturn V rocket was built. Installation activities were supported by the development team from the Payload Operations Control Center (POCC) located at the MSFC and the Mission Control Center at NASA's Johnson Space Flight Center in Houston, Texas.

  7. Automated Robust Maneuver Design and Optimization

    Data.gov (United States)

    National Aeronautics and Space Administration — NASA is seeking improvements to the current technologies related to Position, Navigation and Timing. In particular, it is desired to automate precise maneuver...

  8. Review about hiperventilation test and Valsalva Maneuver

    Directory of Open Access Journals (Sweden)

    Eduardo Antonio MENA-DOMÍNGUEZ

    2018-04-01

    Full Text Available Introduction and objective: With this paper, we pretend to explain the characteristics and the field of application of two clinical explorations used in the patient with suspected vestibular pathology, the hyperventilation maneuver and the Valsalva maneuver. Methodology: Narrative review. Results: Through different neurophysiological mechanisms, hyperventilation can induce nystagmus in cases of vestibular asymmetry, both peripheral and central. The Valsalva maneuver may also trigger nystagmus and vertigo because of direct transmission of internal ear pressure in cases of perilymphatic fistula, anomalies of the cranio-cervical junction (Arnold-Chiari malformation, and other ossicles, oval window and saccule pathologies. Discussion and conclusions: Both the hyperventilation test and the Valsalva maneuver should be included in the battery of tests for patients with vestibular pathology to, depending on the results obtained, anatomically locate the site of the lesion and justify the use of imaging techniques.

  9. Precision Closed-Loop Orbital Maneuvering System Design and Performance for the Magnetospheric Multi-Scale Mission (MMS) Formation

    Science.gov (United States)

    Chai, Dean; Queen, Steve; Placanica, Sam

    2015-01-01

    NASA's Magnetospheric Multi-Scale (MMS) mission successfully launched on March 13, 2015 (UTC) consists of four identically instrumented spin-stabilized observatories that function as a constellation to study magnetic reconnection in space. The need to maintain sufficiently accurate spatial and temporal formation resolution of the observatories must be balanced against the logistical constraints of executing overly-frequent maneuvers on a small fleet of spacecraft. These two considerations make for an extremely challenging maneuver design problem. This paper focuses on the design elements of a 6-DOF spacecraft attitude control and maneuvering system capable of delivering the high-precision adjustments required by the constellation designers---specifically, the design, implementation, and on-orbit performance of the closed-loop formation-class maneuvers that include initialization, maintenance, and re-sizing. The maneuvering control system flown on MMS utilizes a micro-gravity resolution accelerometer sampled at a high rate in order to achieve closed-loop velocity tracking of an inertial target with arc-minute directional and millimeter-per-second magnitude accuracy. This paper summarizes the techniques used for correcting bias drift, sensor-head offsets, and centripetal aliasing in the acceleration measurements. It also discusses the on-board pre-maneuver calibration and compensation algorithms as well as the implementation of the post-maneuver attitude adjustments.

  10. 14 CFR 27.337 - Limit maneuvering load factor.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Limit maneuvering load factor. 27.337... Limit maneuvering load factor. The rotorcraft must be designed for— (a) A limit maneuvering load factor... load factor not less than 2.0 and any negative limit maneuvering load factor of not less than −0.5 for...

  11. 14 CFR 29.337 - Limit maneuvering load factor.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Limit maneuvering load factor. 29.337... Limit maneuvering load factor. The rotorcraft must be designed for— (a) A limit maneuvering load factor... load factor not less than 2.0 and any negative limit maneuvering load factor of not less than −0.5 for...

  12. Optimal Autonomous Spacecraft Resiliency Maneuvers Using Metaheuristics

    Science.gov (United States)

    2014-09-15

    This work was accepted for published by the American Institute of Aeronautics and Astronautics (AIAA) Journal of Spacecraft and Rockets in July 2014...publication in the AIAA Journal of Spacecraft and Rockets . Chapter 5 introduces an impulsive maneuvering strategy to deliver a spacecraft to its final...upon arrival r2 and v2 , respectively. The variable T2 determines the time of flight needed to make the maneuver, and the variable θ2 determines the

  13. Positioning and locking apparatus

    Science.gov (United States)

    Hayward, M.L.; Harper, W.H.

    1985-06-19

    A positioning and locking apparatus including a fixture having a rotatable torque ring provided with a plurality of cam segments for automatically guiding a container into a desired location within the fixture. Rotation of the ring turns the container into a final position in pressure sealing relation against a hatch member.

  14. Locked nucleic acid

    DEFF Research Database (Denmark)

    Jepsen, Jan Stenvang; Sørensen, Mads D; Wengel, Jesper

    2004-01-01

    Locked nucleic acid (LNA) is a class of nucleic acid analogs possessing very high affinity and excellent specificity toward complementary DNA and RNA, and LNA oligonucleotides have been applied as antisense molecules both in vitro and in vivo. In this review, we briefly describe the basic...

  15. Roller Locking Brake

    Science.gov (United States)

    Vranish, John M.

    1993-01-01

    Roller locking brake is normally braking rotary mechanism allowing free rotation when electromagnet in mechanism energized. Well suited to robots and other machinery which automatic braking upon removal of electrical power required. More compact and reliable. Requires little electrical power to maintain free rotation and exhibits minimal buildup of heat.

  16. Locks and Keys Service

    CERN Multimedia

    Claude Ducastel

    The GS-LS-SEM section is pleased to inform you that as from Monday 30 November 2009, the opening hours of the Locks and Keys service will be the following: 08h30 - 12h30 / 13h30 - 16:30, Mondays to Fridays. GS-SEM-LS 73333

  17. Five surgical maneuvers on nasal mucosa movement in cleft palate repair: A cadaver study.

    Science.gov (United States)

    Nguyen, Dennis C; Patel, Kamlesh B; Parikh, Rajiv P; Skolnick, Gary B; Woo, Albert S

    2016-06-01

    This biomechanical study aims to characterize the nasal mucosa during palatoplasty, thereby describing the soft tissue attachments at different zones and quantifying movement following their release. Palatal nasal mucosa was exposed and divided in the midline in 10 adult cadaver heads. Five consecutive maneuvers were performed: (1) elevation of nasal mucosa off the maxilla, (2) dissection of nasal mucosa from soft palate musculature, (3) separation of nasal mucosa from palatine aponeurosis, (4) release of mucosa at the pterygopalatine junction, and (5) mobilization of vomer flaps. The mucosal movements across the midline at the midpalate (MP) and posterior nasal spine (PNS) following each maneuver were measured. At the MP, maneuvers 1-4 cumulatively provided 3.8 mm (36.9%), 4.9 mm (47.6%), 6.1 mm (59.2%), and 10.3 mm, respectively. Vomer flap (10.5 mm) elevation led to mobility equivalent to that of maneuvers 1-4 (p = 0.72). At the PNS, cumulative measurements after maneuvers 1-4 were 1.3 mm (10%), 2.4 mm (18.6%), 5.7 mm (44.2%), and 12.9 mm. Here, vomer flaps (6.5 mm) provided less movement (p < 0.001). Maneuver 4 yielded the greatest amount of movement of the lateral nasal mucosa at both MP (4.2 mm, 40.8%) and PNS (7.2 mm, 55.8%). At the MP, complete release of the lateral nasal mucosa achieves as much movement as the vomer flap. At the hard-soft palate junction, the maneuvers progressively add to the movement of the lateral nasal mucosa. The most powerful step is release of attachments along the posterior aspect of the medial pterygoid. Published by Elsevier Ltd.

  18. Innovation and Lock-in

    DEFF Research Database (Denmark)

    Cantner, Uwe; Vannuccini, Simone

    2016-01-01

    This study focuses on a well-known but yet elusive concept: (technological) lock-in. We summarize what is known about the nature of lock-in and offer a critical view on history-dependent processes based on recent contributions to the literature. We discuss if lock-ins are really inescapable......, especially when innovation is concerned. Also, we address the question if lock-in is a well-defined concept at all. To offer a fresh view on lock-in and to tackle the issues just raised, we employ the replicator dynamics model. By making a parallel between monopolization in the replicator dynamics...... and the occurrence of lock-ins, we show that the convergence of a system to a given outcome can be reversed, under certain conditions. We highlight the need for a more precise demarcation of the conceptual boundaries of lock-in and path dependence, both from the formal and the empirical side, and suggest...

  19. How hummingbirds hum: Acoustic holography of hummingbirds during maneuvering flight

    Science.gov (United States)

    Hightower, Ben; Wijnings, Patrick; Ingersoll, Rivers; Chin, Diana; Scholte, Rick; Lentink, David

    2017-11-01

    Hummingbirds make a characteristic humming sound when they flap their wings. The physics and the biological significance of hummingbird aeroacoustics is still poorly understood. We used acoustic holography and high-speed cameras to determine the acoustic field of six hummingbirds while they either hovered stationary in front of a flower or maneuvered to track flower motion. We used a robotic flower that oscillated either laterally or longitudinally with a linear combination of 20 different frequencies between 0.2 and 20 Hz, a range that encompasses natural flower vibration frequencies in wind. We used high-speed marker tracking to dissect the transfer function between the moving flower, the head, and body of the bird. We also positioned four acoustic arrays equipped with 2176 microphones total above, below, and in front of the hummingbird. Acoustic data from the microphones were back-propagated to planes adjacent to the hummingbird to create the first real-time holograms of the pressure field a hummingbird generates in vivo. Integration of all this data offers insight into how hummingbirds modulate the acoustic field during hovering and maneuvering flight.

  20. Data port security lock

    Science.gov (United States)

    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.

  1. Avoiding lock-in

    DEFF Research Database (Denmark)

    Henriksen, Ingrid

    1999-01-01

    The paper investigates the initial phase of the cooperative organisation of agricultural processing firms in Denmark. It argues that the variations observed can be explained within the framework of the theory of industrial organisation. The focus is on the success of cooperative creameries. In 19...... of gathering information and of preserving and transporting a perishable product, were ideally suited to overcome the problems of potential lock-in and of asymmetric information...

  2. Locking screw apparatus and method for underwater remote replacement

    International Nuclear Information System (INIS)

    Balog, L.J.

    1987-01-01

    A method is described for locking in place a screw which secures together first and second structures in the internal region of a nuclear reactor core. The first structure has a screw bore with a counterbore portion formed in an outer surface. The method comprises the steps of: forming a lateral recess in the counterbore portion and spaced from the outer surface, providing an elongated screw having an enlarged shoulder flange and an angular drive head with a lateral width substantially less than that of the counterbore portion, disposing the screw through the screw bore in threaded engagement with the second structure and with the shoulder rotatably seated in the counterbore portion. This provides a locking member having an angular opening and disposing it in the counterbore portion against the flange with the drive head received in the opening for engagement with the locking member to prevent rotation. This deforms a portion of the locking member into the recess for engagement to prevent movement of the locking member with respect to the first structure

  3. The Dix-Hallpike test and the canalith repositioning maneuver.

    Science.gov (United States)

    Viirre, Erik; Purcell, Ian; Baloh, Robert W

    2005-01-01

    The Dix-Hallpike test and the canalith repositioning maneuver (CRM) are used to diagnose and treat benign positional vertigo (BPV). Dix-Hallpike is the standard procedure for diagnosis of BPV, but if the horizontal canal is not tested for BPV and the Dix-Hallpike is only carried out once, the condition may not be diagnosed and appropriately treated. We describe our method of testing for BPV and treating it with CRM. The Dix-Hallpike test involves rapidly moving the patient from a sitting position to "head hanging," where the patient's head is at least 10 degrees below horizontal. This is performed initially for the posterior semicircular canals. If these movements fail to elicit vertigo and nystagmus, tests of the horizontal semicircular canals are performed by laying the patient on each side. Importantly, if there is no vertigo or nystagmus elicited by testing the horizontal semi-circular canals, the posterior semicircular canals are tested again. It appears that being held in the head hanging positions and then left and right lateral positions will often allow the canaliths to collect such that the Dix-Hallpike test will become positive. Failure to repeat the tests of the posterior semicircular canals may result in a falsely negative test. Testing the horizontal canals and repeating the Dix-Hallpike test will reduce the likelihood of patients undergoing extra testing or other consequences of misdiagnosis. If, during any of this testing, a movement elicits vertigo or nystagmus, the appropriate CRM is then carried out.

  4. The Art and Science of Operational Maneuver,

    Science.gov (United States)

    1988-05-04

    Classification) The Art and Science of Operational Maneuver (U) 12. PERSONAL AUTHOR(S) MAJ Joseph Schroedel 13a. TYPE OF REPORT 13b. TIME COVERED 14...CLASSIFICATION OF THIS PAGE VA) CL LA S F1 EP {fJE ART ANQ SCIENCE OlF OPERAIl NAL MANUVER By6 Mal or Josepi~ Schroeci, L U. S. Arm~y H Aciv -darILC Ced M ili t...Studies ,nIgz’raph ApprovwA. Name of Student: Major Jonevh Schroedel. U.S. Army Title ot Monograph: The Art and Science of Operational Maneuver Approved By

  5. Cassini Solstice Mission Maneuver Experience: Year Two

    Science.gov (United States)

    Arrieta, Juan; Ballard, Christopher G.; Hahn, Yungsun

    2012-01-01

    The Cassini Spacecraft was launched in October 1997 on a mission to observe Saturn and its moons; it entered orbit around Saturn in July 2004 for a nominal four-year Prime Mission, later augmented by two extensions: the Equinox Mission, from July 2008 through September 2010, and the Solstice Mission, from October 2010 through September 2017. This paper provides an overview of the maneuver activities from August 2011 through June 2012 which include the design of 38 Orbit Trim Maneuvers--OTM-288 through OTM-326-- for attaining 14 natural satellite encounters: seven with Titan, six with Enceladus, and one with Dione.

  6. 49 CFR 236.338 - Mechanical locking required in accordance with locking sheet and dog chart.

    Science.gov (United States)

    2010-10-01

    ... locking sheet and dog chart. 236.338 Section 236.338 Transportation Other Regulations Relating to... in accordance with locking sheet and dog chart. Mechanical locking shall be in accordance with locking sheet and dog chart currently in effect. ...

  7. 49 CFR 236.330 - Locking dog of switch-and-lock movement.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Locking dog of switch-and-lock movement. 236.330 Section 236.330 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD... Rules and Instructions § 236.330 Locking dog of switch-and-lock movement. Locking dog of switch-and-lock...

  8. 32 CFR 644.137 - Maneuver agreements.

    Science.gov (United States)

    2010-07-01

    ... planning and acquires rights to use land and other facilities for Department of the Army exercises. The... and, after the maneuver is completed, will be responsible for negotiating restoration settlements and... director at field level whereby the command will assume responsibility for settlement of real estate...

  9. Optimizing interplanetary trajectories with deep space maneuvers

    Science.gov (United States)

    Navagh, John

    1993-09-01

    Analysis of interplanetary trajectories is a crucial area for both manned and unmanned missions of the Space Exploration Initiative. A deep space maneuver (DSM) can improve a trajectory in much the same way as a planetary swingby. However, instead of using a gravitational field to alter the trajectory, the on-board propulsion system of the spacecraft is used when the vehicle is not near a planet. The purpose is to develop an algorithm to determine where and when to use deep space maneuvers to reduce the cost of a trajectory. The approach taken to solve this problem uses primer vector theory in combination with a non-linear optimizing program to minimize Delta(V). A set of necessary conditions on the primer vector is shown to indicate whether a deep space maneuver will be beneficial. Deep space maneuvers are applied to a round trip mission to Mars to determine their effect on the launch opportunities. Other studies which were performed include cycler trajectories and Mars mission abort scenarios. It was found that the software developed was able to locate quickly DSM's which lower the total Delta(V) on these trajectories.

  10. Helicopter noise footprint prediction in unsteady maneuvers

    NARCIS (Netherlands)

    Gennaretti, Massimo; Bernardini, Giovanni; Serafini, Jacopo; Anobile, A.; Hartjes, S.

    2017-01-01

    This paper investigates different methodologies for the evaluation of the acoustic disturbance emitted by helicopter’s main rotors during unsteady maneuvers. Nowadays, the simulation of noise emitted by helicopters is of great interest to designers, both for the assessment of the acoustic impact

  11. About avatars and maneuvering in virtual environments

    NARCIS (Netherlands)

    Delleman, N.

    2006-01-01

    This paper is about the use of avatars and maneuvering in virtual environments for simulation-based design ergonomics. An avatar is a digital human model driven by an instrumented human who is immersed in a virtual environment. A presentation on locomotion devices is followed by descriptions of

  12. Demonstrative Maneuvers for Aircraft Agility Predictions

    Science.gov (United States)

    2008-03-01

    AIAA Paper 1996-3741. 19. Raymer , Daniel P. Aircraft Design: A Conceptual Approach. American Institute of Aeronautics and Astronautics, Inc., 3rd...Shaw, Robert L. Fighter Combat: Tactics and Maneuvering. Naval Institute Press, Annapolis, MD, 1985. 25. Smith, Steven W. The Scientist and

  13. Analysis of risk factors influencing the outcome of the Epley maneuver.

    Science.gov (United States)

    Domínguez-Durán, E; Domènech-Vadillo, E; Álvarez-Morujo de Sande, M G; González-Aguado, R; Guerra-Jiménez, G; Ramos-Macías, Á; Morales-Angulo, C; Martín-Mateos, A J; Figuerola-Massana, E; Galera-Ruiz, H

    2017-10-01

    Benign paroxysmal positional vertigo (BPPV) is the most frequent type of vertigo. The treatment of canalithiasis of the posterior semicircular canal consists in performing a particle-repositioning maneuver, such as the Epley maneuver (EM). However, the EM is not effective in all cases. The objective of this study is to identify risk factors, which predict the EM failure, among the clinical variables recorded in anamnesis and patient examination. This is an observational prospective multicentric study. All patients presenting with BPPV were recruited and applied the EM and appointed for a follow-up visit 7 days later. The following variables were recorded: sex, age, arterial hypertension, diabetes, hyperlipidemia, smoking habit, alcohol consumption, migraine, osteoporosis, diseases of the inner ear, previous ipsilateral BPPV, previous traumatic brain injury, previous sudden head deceleration, time of evolution, sulpiride or betahistine treatment, experienced symptoms, outcome of the Halmagyi maneuver, laterality, cephalic hyperextension of the neck, intensity of nystagmus, intensity of vertigo, duration of nystagmus, occurrence of orthotropic nystagmus, symptoms immediately after the EM, postural restrictions, and symptoms 7 days after the EM. Significant differences in the rate of loss of nystagmus were found for six variables: hyperlipidemia, previous ipsilateral BPPV, intensity of nystagmus, duration of nystagmus, post-maneuver sweating, and subjective status. The most useful significant variables in the clinical practice to predict the success of the EM are previous BPPV and intensity of nystagmus. In the other significant variables, no physiopathological hypothesis can be formulated or differences between groups are too small.

  14. 23 CFR 660.517 - Maneuver area roads.

    Science.gov (United States)

    2010-04-01

    ... 23 Highways 1 2010-04-01 2010-04-01 false Maneuver area roads. 660.517 Section 660.517 Highways... PROGRAMS (DIRECT FEDERAL) Defense Access Roads § 660.517 Maneuver area roads. (a) Claims by a highway agency for costs incurred to restore, to their former condition, roads damaged by maneuvers involving a...

  15. Breaking Carbon Lock-in

    DEFF Research Database (Denmark)

    Driscoll, Patrick Arthur

    2014-01-01

    This central focus of this paper is to highlight the ways in which path dependencies and increasing returns (network effects) serve to reinforce carbon lock-in in large-scale road transportation infrastructure projects. Breaking carbon lock-in requires drastic changes in the way we plan future...

  16. Homodyne locking of a squeezer.

    Science.gov (United States)

    Heurs, M; Petersen, I R; James, M R; Huntington, E H

    2009-08-15

    We report on the successful implementation of an approach to locking the frequencies of an optical parametric oscillator (OPO)-based squeezed-vacuum source and its driving laser. The technique allows the simultaneous measurement of the phase shifts induced by a cavity, which may be used for the purposes of frequency locking, as well as the simultaneous measurement of the sub-quantum-noise-limited (sub-QNL) phase quadrature output of the OPO. The homodyne locking technique is cheap, easy to implement, and has the distinct advantage that subsequent homodyne measurements are automatically phase locked. The homodyne locking technique is also unique in that it is a sub-QNL frequency discriminator.

  17. Payload Launch Lock Mechanism

    Science.gov (United States)

    Young, Ken (Inventor); Hindle, Timothy (Inventor)

    2014-01-01

    A payload launch lock mechanism includes a base, a preload clamp, a fastener, and a shape memory alloy (SMA) actuator. The preload clamp is configured to releasibly restrain a payload. The fastener extends, along an axis, through the preload clamp and into the base, and supplies a force to the preload clamp sufficient to restrain the payload. The SMA actuator is disposed between the base and the clamp. The SMA actuator is adapted to receive electrical current and is configured, upon receipt of the electrical current, to supply a force that causes the fastener to elongate without fracturing. The preload clamp, in response to the fastener elongation, either rotates or pivots to thereby release the payload.

  18. Estimating maneuvers for precise relative orbit determination using GPS

    Science.gov (United States)

    Allende-Alba, Gerardo; Montenbruck, Oliver; Ardaens, Jean-Sébastien; Wermuth, Martin; Hugentobler, Urs

    2017-01-01

    Precise relative orbit determination is an essential element for the generation of science products from distributed instrumentation of formation flying satellites in low Earth orbit. According to the mission profile, the required formation is typically maintained and/or controlled by executing maneuvers. In order to generate consistent and precise orbit products, a strategy for maneuver handling is mandatory in order to avoid discontinuities or precision degradation before, after and during maneuver execution. Precise orbit determination offers the possibility of maneuver estimation in an adjustment of single-satellite trajectories using GPS measurements. However, a consistent formulation of a precise relative orbit determination scheme requires the implementation of a maneuver estimation strategy which can be used, in addition, to improve the precision of maneuver estimates by drawing upon the use of differential GPS measurements. The present study introduces a method for precise relative orbit determination based on a reduced-dynamic batch processing of differential GPS pseudorange and carrier phase measurements, which includes maneuver estimation as part of the relative orbit adjustment. The proposed method has been validated using flight data from space missions with different rates of maneuvering activity, including the GRACE, TanDEM-X and PRISMA missions. The results show the feasibility of obtaining precise relative orbits without degradation in the vicinity of maneuvers as well as improved maneuver estimates that can be used for better maneuver planning in flight dynamics operations.

  19. Locked Twins: A Rarity

    African Journals Online (AJOL)

    On examination, her vitals were stable. Per abdominal examination revealed uterine fundal height of 28 weeks' size and a fetal heart rate of 136 beats/minute, auscultated just above the level of the umbilicus. No heart sound was found for the first baby. Vaginal examination showed the head of the second baby. [Figure 1].

  20. Colisional Cloud Debris and Propelled Evasive Maneuvers

    Science.gov (United States)

    Ferreira, L. S.; Jesus, A. D. C.; Carvalho, T. C. F.; Sousa, R. R.

    2017-10-01

    Space debris clouds exist at various altitudes in the environment outside the Earth. Fragmentation of debris and/or collision between the debris of a cloud increases the amount of debris, producing smaller debris. This event also increases significantly the chances of collision with operational vehicles in orbit. In this work we study clouds of debris that are close to a spacecraft in relation to its distance from the center of the Earth. The results show several layers of colliding debris depending on their size over time of evasive maneuvers of the vehicle. In addition, we have tested such maneuvers for propulsion systems with a linear and exponential mass variation model. The results show that the linear propulsion system is more efficient.

  1. Review of Tracktable for Satellite Maneuver Detection

    Energy Technology Data Exchange (ETDEWEB)

    Acquesta, Erin C.S. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Valicka, Christopher G. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Hinga, Mark B. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Ehn, Carollan Beret [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2016-10-01

    As a tool developed to translate geospatial data into geometrical descriptors, Tracktable offers a highly efficient means to detect anomalous flight and maritime behavior. Following the success of using geometrical descriptors for detecting anomalous trajectory behavior, the question of whether Tracktable could be used to detect satellite maneuvers arose. In answering this question, this re- port will introduce a brief description of how Tracktable has been used in the past, along with an introduction to the fundamental properties of astrodynamics for satellite trajectories. This will then allow us to compare the two problem spaces, addressing how easily the methods used by Tracktable will translate to orbital mechanics. Based on these results, we will then be able to out- line the current limitations as well as possible path forward for using Tracktable to detect satellite maneuvers.

  2. Identifying tacit strategies in aircraft maneuvers

    Science.gov (United States)

    Lewis, Charles M.; Heidorn, P. B.

    1991-01-01

    Two machine-learning methods are presently used to characterize the avoidance strategies used by skilled pilots in simulated aircraft encounters, and a general framework for the characterization of the strategic components of skilled behavior via qualitative representation of situations and responses is presented. Descriptions of pilot maneuvers that were 'conceptually equivalent' were ascertained by a concept-learning algorithm in conjunction with a classifier system that employed a generic algorithm; satisficing and 'buggy' strategies were thereby revealed.

  3. Decisive Army Strategic and Expeditionary Maneuver

    Science.gov (United States)

    2015-05-01

    emerging changes will impact strategic maneuver by 2025. For example, a rapid transition is occurring in the commercial air cargo market where 777...more readily available in the international defense market and in the inventories of potential adversaries. In short, the study team believes HPMs... Cisco Visual Networking Index (VNI), available at: http://www.cisco.com/c/en/us/solutions/collateral/service-provider/visual-networking-index- vni

  4. Mars Exploration Rovers Propulsive Maneuver Design

    Science.gov (United States)

    Potts, Christopher L.; Raofi, Behzad; Kangas, Julie A.

    2004-01-01

    The Mars Exploration Rovers Spirit and Opportunity successfully landed respectively at Gusev Crater and Meridiani Planum in January 2004. The rovers are essentially robotic geologists, sent on a mission to search for evidence in the rocks and soil pertaining to the historical presence of water and the ability to possibly sustain life. In order to conduct NASA's 'follow the water' strategy on opposite sides of the planet Mars, an interplanetary journey of over 300 million miles culminated with historic navigation precision. Rigorous trajectory targeting and control was necessary to achieve the atmospheric entry requirements for the selected landing sites. The propulsive maneuver design challenge was to meet or exceed these requirements while preserving the necessary design margin to accommodate additional project concerns. Landing site flexibility was maintained for both missions after launch, and even after the first trajectory correction maneuver for Spirit. The final targeting strategy was modified to improve delivery performance and reduce risk after revealing constraining trajectory control characteristics. Flight results are examined and summarized for the six trajectory correction maneuvers that were planned for each mission.

  5. Heads Up

    Science.gov (United States)

    ... Connect with Us HEADS UP Apps Reshaping the Culture Around Concussion in Sports Get HEADS UP on Your Web Site Concussion ... HEADS UP on your web site! Create a culture of safety for young athletes Officials, learn how you can ... UP to Providers HEADS UP to Youth Sports HEADS UP to School Sports HEADS UP to ...

  6. Design and Simulation of the Robust ABS and ESP Fuzzy Logic Controller on the Complex Braking Maneuvers

    Directory of Open Access Journals (Sweden)

    Andrei Aksjonov

    2016-11-01

    Full Text Available Automotive driving safety systems such as an anti-lock braking system (ABS and an electronic stability program (ESP assist drivers in controlling the vehicle to avoid road accidents. In this paper, ABS and the ESP, based on the fuzzy logic theory, are integrated for vehicle stability control in complex braking maneuvers. The proposed control algorithm is implemented for a sport utility vehicle (SUV and investigated for braking on different surfaces. The results obtained for the vehicle software simulator confirm the robustness of the developed control strategy for a variety of road profiles and surfaces.

  7. 49 CFR 236.765 - Locking, mechanical.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Locking, mechanical. 236.765 Section 236.765 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION... Locking, mechanical. An arrangement of locking bars, dogs, tappets, cross locking and other apparatus by...

  8. Escaping carbon lock-in

    International Nuclear Information System (INIS)

    Unruh, G.C.

    2002-01-01

    This article explores the climate policy implications of the arguments made in ''Understanding carbon lock-in'' (Unruh, 2000), which posited that industrial countries have become locked-into fossil fuel-based energy systems through path dependent processes driven by increasing returns to scale. Carbon lock-in arises through technological, organizational, social and institutional co-evolution, ''culminating'' in what was termed as techno-institutional complex (TIC). In order to resolve the climate problem, an escape from the lock-in condition is required. However, due to the self-referential nature of TIC, escape conditions are unlikely to be generated internally and it is argued here that erogenous forces are probably required. (author)

  9. Globalizing carbon lock-in

    International Nuclear Information System (INIS)

    Unruh, Gregory C.; Carrillo-Hermosilla, Javier

    2006-01-01

    This paper extends the arguments surrounding carbon lock-in elaborated in Unruh (Energy Policy 28 (2000) 817; 30 (2002) 317) to countries currently undergoing industrialization. It argues that, for numerous reasons, industrializing countries are unlikely to leapfrog carbon intensive energy development. On the contrary, carbon lock-in may be globalizing and could further constrain climate change mitigation options. It is then argued that many policy recommendations ignore carbon lock-in, possibly limiting their potential for successful implementation. The paper then discusses four policy approaches that appear to have advantages given lock-in conditions. It is recognized, however, that relative ease of implementation does not necessarily equate with superiority. Instead, it is merely a path dependent outcome of past development decisions. Pursuing policies on the basis of relative implementation ease may help address the issue of climate change, but could also result in sub-optimal outcomes along other dimensions of sustainable development

  10. Research of mechanism of density lock

    International Nuclear Information System (INIS)

    Wang Shengfei; Yan Changqi; Gu Haifeng

    2010-01-01

    Mechanism of density lock was analyzed according to the work conditions of density lock. The results showed that: the stratification with no disturbance satisfied the work conditions of density lock; fluids between the stratification were not mixed at the condition of connected to each other; the density lock can be open automatically by controlled the pressure balance at the stratification. When disturbance existed, the stratification might be broken and mass would be transferred by convection. The stability of stratification can be enhanced by put the special structure in density lock to ensure the normal work of density lock. At last, the minimum of heat loss in density lock was also analyzed. (authors)

  11. Hew Locke: House of Cards

    OpenAIRE

    Reckitt, Helena; Joyce, Julie; Locke, Hew

    2004-01-01

    ‘Hew Locke: House of Cards’ featured a selection of the artist's portraits of British royalty in various media, and his response to other trappings of the monarchy and empire. The show included works previously exhibited at the Luckman Gallery, Los Angeles, in tandem with a newly commissioned coat of arms, and other recent works. \\ud \\ud Locke draws from everyday sources, ranging from items found in London's Brixton Market to discount fabric shops and thrift stores. Other sources of inspirati...

  12. John locke on personal identity.

    Science.gov (United States)

    Nimbalkar, Namita

    2011-01-01

    John Locke speaks of personal identity and survival of consciousness after death. A criterion of personal identity through time is given. Such a criterion specifies, insofar as that is possible, the necessary and sufficient conditions for the survival of persons. John Locke holds that personal identity is a matter of psychological continuity. He considered personal identity (or the self) to be founded on consciousness (viz. memory), and not on the substance of either the soul or the body.

  13. John Locke on Personal Identity**

    OpenAIRE

    Nimbalkar, Namita

    2011-01-01

    John Locke speaks of personal identity and survival of consciousness after death. A criterion of personal identity through time is given. Such a criterion specifies, insofar as that is possible, the necessary and sufficient conditions for the survival of persons. John Locke holds that personal identity is a matter of psychological continuity. He considered personal identity (or the self) to be founded on consciousness (viz. memory), and not on the substance of either the soul or the body.

  14. Biomechanics of far cortical locking.

    Science.gov (United States)

    Bottlang, Michael; Feist, Florian

    2011-02-01

    The development of far cortical locking (FCL) was motivated by a conundrum: locked plating constructs provide inherently rigid stabilization, yet they should facilitate biologic fixation and secondary bone healing that relies on flexible fixation to stimulate callus formation. Recent studies have confirmed that the high stiffness of standard locked plating constructs can suppress interfragmentary motion to a level that is insufficient to reliably promote secondary fracture healing by callus formation. Furthermore, rigid locking screws cause an uneven stress distribution that may lead to stress fracture at the end screw and stress shielding under the plate. This review summarizes four key features of FCL constructs that have been shown to enhance fixation and healing of fractures: flexible fixation, load distribution, progressive stiffening, and parallel interfragmentary motion. Specifically, flexible fixation provided by FCL reduces the stiffness of a locked plating construct by 80% to 88% to actively promote callus proliferation similar to an external fixator. Load is evenly distributed between FCL screws to mitigate stress risers at the end screw. Progressive stiffening occurs by near cortex support of FCL screws and provides additional support under elevated loading. Finally, parallel interfragmentary motion by the S-shaped flexion of FCL screws promotes symmetric callus formation. In combination, these features of FCL constructs have been shown to induce more callus and to yield significantly stronger and more consistent healing compared with standard locked plating constructs. As such, FCL constructs function as true internal fixators by replicating the biomechanical behavior and biologic healing response of external fixators.

  15. Outdraft at Lock Approach, Tom Bevill Lock and Dam, Alabama: Hydraulic Model Investigation

    National Research Council Canada - National Science Library

    Lynch, Gary

    2001-01-01

    .... The lock is connected to the dam with a 150-ft abutment wall. A strong crosscurrent or outdraft existing in and around the upstream lock entrance causes difficulty for tow traffic navigating the lock...

  16. Aqua/Aura Updated Inclination Adjust Maneuver Performance Prediction Model

    Science.gov (United States)

    Boone, Spencer

    2017-01-01

    This presentation will discuss the updated Inclination Adjust Maneuver (IAM) performance prediction model that was developed for Aqua and Aura following the 2017 IAM series. This updated model uses statistical regression methods to identify potential long-term trends in maneuver parameters, yielding improved predictions when re-planning past maneuvers. The presentation has been reviewed and approved by Eric Moyer, ESMO Deputy Project Manager.

  17. Marine Corps Maneuver Squad Leader Mastery Model

    Science.gov (United States)

    2012-12-17

    H. L., & Dreyfus, S. E. (1986). Mind over machine: The power of human intuitive expertise in the  era of the computer. New York: The  Free  Press...at them then  squat  down to begin playing a dice game. The  maneuver squad leader judged this behavior as an anomaly, because  the boys didn’t begin

  18. Coordination Logic for Repulsive Resolution Maneuvers

    Science.gov (United States)

    Narkawicz, Anthony J.; Munoz, Cesar A.; Dutle, Aaron M.

    2016-01-01

    This paper presents an algorithm for determining the direction an aircraft should maneuver in the event of a potential conflict with another aircraft. The algorithm is implicitly coordinated, meaning that with perfectly reliable computations and information, it will in- dependently provide directional information that is guaranteed to be coordinated without any additional information exchange or direct communication. The logic is inspired by the logic of TCAS II, the airborne system designed to reduce the risk of mid-air collisions between aircraft. TCAS II provides pilots with only vertical resolution advice, while the proposed algorithm, using a similar logic, provides implicitly coordinated vertical and horizontal directional advice.

  19. Assessing carbon lock-in

    International Nuclear Information System (INIS)

    Erickson, Peter; Kartha, Sivan; Lazarus, Michael; Tempest, Kevin

    2015-01-01

    The term ‘carbon lock-in’ refers to the tendency for certain carbon-intensive technological systems to persist over time, ‘locking out’ lower-carbon alternatives, and owing to a combination of linked technical, economic, and institutional factors. These technologies may be costly to build, but relatively inexpensive to operate and, over time, they reinforce political, market, and social factors that make it difficult to move away from, or ‘unlock’ them. As a result, by investing in assets prone to lock-in, planners and investors restrict future flexibility and increase the costs of achieving agreed climate protection goals. Here, we develop a straight-forward approach to assess the speed, strength, and scale of carbon lock-in for major energy-consuming assets in the power, buildings, industry, and transport sectors. We pilot the approach at the global level, finding that carbon lock-in is greatest, globally, for coal power plants, gas power plants, and oil-based vehicles. The approach can be readily applied at the national or regional scale, and may be of particular relevance to policymakers interested in enhancing flexibility in their jurisdictions for deeper emissions cuts in the future, and therefore in limiting the future costs associated with ‘stranded assets’. (letter)

  20. Mueller-Hillis maneuver and angle of progression: Are they correlated?

    Directory of Open Access Journals (Sweden)

    Sofia Mendes

    Full Text Available Summary Objective: Mueller-Hillis maneuver (MHM and angle of progression (AOP measured by transperineal ultrasound have been used to assess fetal head descent during the second stage of labor. We aimed to assess whether AOP correlates with MHM in the second stage of labor. Method: A prospective observational study including women with singleton pregnancy in the second stage of labor was performed. The AOP was measured immediately after the Mueller-Hillis maneuver. A receiver-operating characteristics (ROC curve analysis was performed to determine the best discriminatory AOP cut-off for the identification of a positive MHM. A p-value less than 0.05 was considered statistically significant. Results: One hundred and sixty-six (166 women were enrolled in the study and 81.3% (n=135 had a positive MHM. The median AOP was 143º (106º to 210º. The area under the curve for the prediction of a positive maneuver was 0.619 (p=0.040. Derived from the ROC curve, an AOP of 138.5º had the best diagnostic performance for the identification of a positive MHM (specificity of 65% and a sensitivity of 67%. Conclusion: An AOP of 138º seems to be associated with a positive MHM in the second stage of labor.

  1. ESBWR power maneuvering via feedwater temperature control

    International Nuclear Information System (INIS)

    Saha, P.; Marquino, W.; Tucker, L. J.

    2008-01-01

    The ESBWR is a Generation III+ Boiling Water Reactor (BWR) driven by natural circulation. For a given geometry/hardware, system pressure, downcomer water level and feedwater temperature, the core flow rate in the ESBWR is only a function of reactor power, controlled through the control blade movement. In order to provide operational flexibility, another method of core-wide or global power maneuvering via feedwater temperature control has been developed. This is independent of power maneuvering via control blade movement, and it lowers the linear heat generation rate (LHGR) changes near the tip of control blades, which improves fuel reliability. All required stability, anticipated operational occurrences (AOOs), infrequent events, special events including anticipated transients without scram (ATWS), and loss-of-coolant accident (LOCA) analyses have been performed for the 4500 MWt ESBWR. Based on the results of these analyses at 'high', nominal and 'low' feedwater temperatures, a safe Power - Feedwater Temperature operating domain has been developed. This paper summarizes the results of these analyses and presents the ESBWR Power - Feedwater Temperature operating domain or map. (authors)

  2. Anatomical basis of the liver hanging maneuver.

    Science.gov (United States)

    Trotovsek, Blaz; Belghiti, Jacques; Gadzijev, Eldar M; Ravnik, Dean; Hribernik, Marija

    2005-01-01

    The anterior approach to right hepatectomy using the liver hanging maneuver without liver mobilization claims to be anatomically evaluated. During this procedure a 4 to 6-cm blind dissection between the inferior vena cava and the liver is performed. Short subhepatic veins, entering the inferior vena cava could be torn and a hemorrhage, difficult to control, could occur. On 100 corrosive casts of livers the anterior surface of the inferior vena cava was studied to evaluate the position, diameter and draining area of short subhepatic veins and inferior right hepatic vein. The width of the narrowest point on the planned route of blind dissection was determined. The average value of the narrowest point on the planned route of blind dissection was 8.7+/-2.3mm (range 2-15mm). The ideal angle of dissection being 0 degrees was found in 93% of cases. In 7% we found the angle of 5 degrees toward the right border of inferior vena cava to be the better choice. Our results show that liver hanging maneuver is a safe procedure. With the dissection in the proposed route the risk of disrupting short subhepatic veins is low (7%).

  3. General and Specific Strategies Used to Facilitate Locomotor Maneuvers.

    Directory of Open Access Journals (Sweden)

    Mengnan Wu

    Full Text Available People make anticipatory changes in gait patterns prior to initiating a rapid change of direction. How they prepare will change based on their knowledge of the maneuver. To investigate specific and general strategies used to facilitate locomotor maneuvers, we manipulated subjects' ability to anticipate the direction of an upcoming lateral "lane-change" maneuver. To examine specific anticipatory adjustments, we observed the four steps immediately preceding a maneuver that subjects were instructed to perform at a known time in a known direction. We hypothesized that to facilitate a specific change of direction, subjects would proactively decrease margin of stability in the future direction of travel. Our results support this hypothesis: subjects significantly decreased lateral margin of stability by 69% on the side ipsilateral to the maneuver during only the step immediately preceding the maneuver. This gait adaptation may have improved energetic efficiency and simplified the control of the maneuver. To examine general anticipatory adjustments, we observed the two steps immediately preceding the instant when subjects received information about the direction of the maneuver. When the maneuver direction was unknown, we hypothesized that subjects would make general anticipatory adjustments that would improve their ability to actively initiate a maneuver in multiple directions. This second hypothesis was partially supported as subjects increased step width and stance phase hip flexion during these anticipatory steps. These modifications may have improved subjects' ability to generate forces in multiple directions and maintain equilibrium during the onset and execution of the rapid maneuver. However, adapting these general anticipatory strategies likely incurred an additional energetic cost.

  4. Coupled optical resonance laser locking.

    Science.gov (United States)

    Burd, S C; du Toit, P J W; Uys, H

    2014-10-20

    We have demonstrated simultaneous laser frequency stabilization of a UV and IR laser, to coupled transitions of ions in the same spectroscopic sample, by detecting only the absorption of the UV laser. Separate signals for locking the different lasers are obtained by modulating each laser at a different frequency and using lock-in detection of a single photodiode signal. Experimentally, we simultaneously lock a 369 nm and a 935 nm laser to the (2)S(1/2) → (2)(P(1/2) and (2)D(3/2) → (3)D([3/2]1/2) transitions, respectively, of Yb(+) ions generated in a hollow cathode discharge lamp. Stabilized lasers at these frequencies are required for cooling and trapping Yb(+) ions, used in quantum information and in high precision metrology experiments. This technique should be readily applicable to other ion and neutral atom systems requiring multiple stabilized lasers.

  5. Automatic locking knee brace joint

    Science.gov (United States)

    Weddendorf, Bruce (Inventor)

    1995-01-01

    This invention is an apparatus for controlling the pivotal movement of a knee brace comprising a tang-and-clevis joint that has been uniquely modified. Both the tang and the clevis have a set of teeth that, when engaged, can lock the tang and the clevis together. In addition, the tang is biased away from the clevis. Consequently, when there is no axial force (i.e., body weight) on the tang, the tang is free to pivot within the clevis. However, when an axial force is exerted on the tang, the tang is pushed into the clevis, both sets of teeth engage, and the tang and the clevis lock together.

  6. Linking spatial and dynamic models for traffic maneuvers

    DEFF Research Database (Denmark)

    Olderog, Ernst-Rüdiger; Ravn, Anders Peter; Wisniewski, Rafal

    2015-01-01

    For traffic maneuvers of multiple vehicles on highways we build an abstract spatial and a concrete dynamic model. In the spatial model we show the safety (collision freedom) of lane-change maneuvers. By linking the spatial and dynamic model via suitable refinements of the spatial atoms to distance...

  7. 14 CFR 23.155 - Elevator control force in maneuvers.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Elevator control force in maneuvers. 23.155 Section 23.155 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION... Controllability and Maneuverability § 23.155 Elevator control force in maneuvers. (a) The elevator control force...

  8. Safety analysis of passing maneuvers using extreme value theory

    Directory of Open Access Journals (Sweden)

    Haneen Farah

    2017-04-01

    The results indicate that this is a promising approach for safety evaluation. On-going work of the authors will attempt to generalize this method to other safety measures related to passing maneuvers, test it for the detailed analysis of the effect of demographic factors on passing maneuvers' crash probability and for its usefulness in a traffic simulation environment.

  9. PWR integral tie plate and locking mechanism

    International Nuclear Information System (INIS)

    Flora, B.S.; Osborne, J.L.

    1980-01-01

    A locking mechanism for securing an upper tie plate to the tie rods of a nuclear fuel bundle is described. The mechanism includes an upper tie plate assembly and locking sleeves fixed to the ends of the tie rods. The tie plate is part of the upper tie plate assembly and is secured to the fuel bundle by securing the entire upper tie plate assembly to the locking sleeves fixed to the tie rods. The assembly includes, in addition to the tie plate, locking nuts for engaging the locking sleeves, retaining sleeves to operably connect the locking nuts to the assembly, a spring biased reaction plate to restrain the locking nuts in the locked position and a means to facilitate the removal of the entire assembly as a unit from the fuel bundle

  10. Adaptive Maneuvering Frequency Method of Current Statistical Model

    Institute of Scientific and Technical Information of China (English)

    Wei Sun; Yongjian Yang

    2017-01-01

    Current statistical model(CSM) has a good performance in maneuvering target tracking. However, the fixed maneuvering frequency will deteriorate the tracking results, such as a serious dynamic delay, a slowly converging speedy and a limited precision when using Kalman filter(KF) algorithm. In this study, a new current statistical model and a new Kalman filter are proposed to improve the performance of maneuvering target tracking. The new model which employs innovation dominated subjection function to adaptively adjust maneuvering frequency has a better performance in step maneuvering target tracking, while a fluctuant phenomenon appears. As far as this problem is concerned, a new adaptive fading Kalman filter is proposed as well. In the new Kalman filter, the prediction values are amended in time by setting judgment and amendment rules,so that tracking precision and fluctuant phenomenon of the new current statistical model are improved. The results of simulation indicate the effectiveness of the new algorithm and the practical guiding significance.

  11. Planar reorientation maneuvers of space multibody systems using internal controls

    Science.gov (United States)

    Reyhanoglu, Mahmut; Mcclamroch, N. H.

    1992-01-01

    In this paper a reorientation maneuvering strategy for an interconnection of planar rigid bodies in space is developed. It is assumed that there are no exogeneous torques, and torques generated by joint motors are used as means of control so that the total angular momentum of the multibody system is a constant, assumed to be zero in this paper. The maneuver strategy uses the nonintegrability of the expression for the angular momentum. We demonstrate that large-angle maneuvers can be designed to achieve an arbitrary reorientation of the multibody system with respect to an inertial frame. The theoretical background for carrying out the required maneuvers is briefly summarized. Specifications and computer simulations of a specific reorientation maneuver, and the corresponding control strategies, are described.

  12. AIRCRAFT CONFLICTS RESOLUTION BY COURSE MANEUVERING

    Directory of Open Access Journals (Sweden)

    В. Харченко

    2011-02-01

    Full Text Available Enhancement of requirements for air traffic efficiency at increasing of flights intensity determines the necessity of development of new optimization methods for aircraft conflict resolutions. The statement of problem of optimal conflict resolutions at Cooperative Air Traffic Management was done. The method for optimal aircraft conflict  resolution by course maneuvering has been  developed. The method using dynamic programming provides planning of aircraft conflict-free trajectory with minimum length. The decomposition of conflict resolution process on phases and stages, definition of states, controls and recursive  equations for generation of optimal course control program were done. Computer modeling of aircraft conflict resolution by developed method was done

  13. Displaced proximal humeral fractures: an Indian experience with locking plates

    Directory of Open Access Journals (Sweden)

    Aggarwal Sameer

    2010-08-01

    Full Text Available Abstract Background The treatment of displaced proximal humerus fractures, especially in elderly, remains controversial. The objective of this study was to evaluate functional outcome of locking plate used for fixation of these fractures after open reduction. We also attempted to evaluate the complications and predictors of loss of fixation for such an implant. Methods Over two and a half years, 56 patients with an acute proximal humerus fracture were managed with locking plate osteosynthesis. 47 of these patients who completed a minimum follow up of 1 year were evaluated using Constant score calculation. Statistical analysis was done using SPSS 16 and a p value of less than 0.05 was taken as statistically significant. Results The average follow up period was around 21.5 months. Outcomes were excellent in 17%, good in 38.5%, moderate in 34% while poor in 10.5%. The Constant score was poorer for AO-OTA type 3 fractures as compared to other types. The scores were also inferior for older patients (> 65 years old. Complications included screw perforation of head, AVN, subacromial impingement, loss of fixation, axillary nerve palsy and infection. A varus malalignment was found to be a strong predictor of loss of fixation. Conclusion Locking plate osteosynthesis leads to satisfactory functional outcomes in all the patients. Results are better than non locking plates in osteoporotic fractures of the elderly. However the surgery has steep learning curve and various complications could be associated with its use. Nevertheless we believe that a strict adherence to the principles of locking plate use can ensure good result in such challenging fractures.

  14. Analysis of ship maneuvering data from simulators

    Science.gov (United States)

    Frette, V.; Kleppe, G.; Christensen, K.

    2011-03-01

    We analyze complex manuevering histories of ships obtained from training sessions on bridge simulators. Advanced ships are used in fields like offshore oil exploration: dive support vessels, supply vessels, anchor handling vessels, tugs, cable layers, and multi-purpose vessels. Due to high demands from the operations carried out, these ships need to have very high maneuverability. This is achieved through a propulsion system with several thrusters, water jets, and rudders in addition to standard propellers. For some operations, like subsea maintenance, it is crucial that the ship accurately keeps a fixed position. Therefore, bridge systems usually incorporate equipment for Dynamic Positioning (DP). DP is a method to keep ships and semi submersible rigs in a fixed position using the propulsion systems instead of anchors. It may also be used for sailing a vessel from one position to another along a predefined route. Like an autopilot on an airplane, DP may operate without human involvement. The method relies on accurate determination of position from external reference systems like GPS, as well as a continuously adjusted mathematical model of the ship and external forces from wind, waves and currents. In a specific simulator exercise for offshore crews, a ship is to be taken up to an installation consisting of three nearby oil platforms connected by bridges (Frigg field, North Sea), where a subsea inspection is to be carried out. Due to the many degrees of freedom during maneuvering, including partly or full use of DP, the chosen routes vary significantly. In this poster we report preliminary results on representations of the complex maneuvering histories; representations that allow comparison between crew groups, and, possibly, sorting of the different strategic choices behind.

  15. The variable finesse locking technique

    International Nuclear Information System (INIS)

    Acernese, F; Al-Shourbagy, M

    2006-01-01

    Virgo is a power recycled Michelson interferometer, with 3 km long Fabry-Perot cavities in the arms. The locking of the interferometer has been obtained with an original lock acquisition technique. The main idea is to lock the instrument away from its working point. Lock is obtained by misaligning the power recycling mirror and detuning the Michelson from the dark fringe. In this way, a good fraction of light escapes through the antisymmetric port and the power build-up inside the recycling cavity is extremely low. The benefit is that all the degrees of freedom are controlled when they are almost decoupled, and the linewidth of the recycling cavity is large. The interferometer is then adiabatically brought on to the dark fringe. This technique is referred to as variable finesse, since the recycling cavity is considered as a variable finesse Fabry-Perot. This technique has been widely tested and allows us to reach the dark fringe in few minutes, in an essentially deterministic way

  16. Coupled optical resonance laser locking

    CSIR Research Space (South Africa)

    Burd, CC

    2014-10-01

    Full Text Available We have demonstrated simultaneous laser frequency stabilization of a UV and IR laser, to coupled transitions of ions in the same spectroscopic sample, by detecting only the absorption of the UV laser. Separate signals for locking the different...

  17. Advances phase-lock techniques

    CERN Document Server

    Crawford, James A

    2008-01-01

    From cellphones to micrprocessors, to GPS navigation, phase-lock techniques are utilized in most all modern electronic devices. This high-level book takes a systems-level perspective, rather than circuit-level, which differentiates it from other books in the field.

  18. Hip Dislocation and Dystocia in Early Medieval Times: Possible Evidence of Labor Maneuver.

    Science.gov (United States)

    Malgosa, Assumpció; Carrascal, Susana; Piga, Giampaolo; Isidro, Albert

    2016-12-01

    In ancient times, maternal mortality would occur frequently, particularly during labor. Evidence of dystocia resulting in the death of a pregnant woman is very infrequent in paleopathologic literature, with only a few cases being demonstrated. In the early medieval site of Casserres, the skeleton of a young woman with a fetus in the pelvic region was found. Some abnormal findings of the maternal skeleton were evaluated, including a sacral anomaly, femoral head wound, the rare position of the lower left limb with the femoral head dislodged anteriorly and cephalad from the socket, and a fibular fracture. Examining the anomalies all together, a case of anterior hip dislocation related to a McRoberts-like maneuver performed during labor is a plausible explanation of the findings.

  19. 49 CFR 236.705 - Bar, locking.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Bar, locking. 236.705 Section 236.705..., MAINTENANCE, AND REPAIR OF SIGNAL AND TRAIN CONTROL SYSTEMS, DEVICES, AND APPLIANCES Definitions § 236.705 Bar, locking. A bar in an interlocking machine to which the locking dogs are attached. ...

  20. Bilateral locked facets in the thoracic spine

    NARCIS (Netherlands)

    M.H.A. Willems; Braakman, R. (Reinder); B. van Linge (Bert)

    1984-01-01

    textabstractTwo cases of traumatic bilateral locked facets in the thoracic spine are reported. Both patients had only minor neurological signs. They both made a full neurological recovery after surgical reduction of the locked facets. Bilateral locked facets are very uncommon in the thoracic spine.

  1. 49 CFR 236.761 - Locking, electric.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Locking, electric. 236.761 Section 236.761 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION... Locking, electric. The combination of one or more electric locks and controlling circuits by means of...

  2. 49 CFR 236.105 - Electric lock.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Electric lock. 236.105 Section 236.105 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION...: All Systems Inspections and Tests; All Systems § 236.105 Electric lock. Electric lock, except forced...

  3. 49 CFR 236.757 - Lock, electric.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Lock, electric. 236.757 Section 236.757... Lock, electric. A device to prevent or restrict the movement of a lever, a switch or a movable bridge, unless the locking member is withdrawn by an electrical device, such as an electromagnet, solenoid or...

  4. 49 CFR 236.768 - Locking, time.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Locking, time. 236.768 Section 236.768... Locking, time. A method of locking, either mechanical or electrical, which, after a signal has been caused to display an aspect to proceed, prevents, until after the expiration of a predetermined time...

  5. Tidal locking of habitable exoplanets

    Science.gov (United States)

    Barnes, Rory

    2017-12-01

    Potentially habitable planets can orbit close enough to their host star that the differential gravity across their diameters can produce an elongated shape. Frictional forces inside the planet prevent the bulges from aligning perfectly with the host star and result in torques that alter the planet's rotational angular momentum. Eventually the tidal torques fix the rotation rate at a specific frequency, a process called tidal locking. Tidally locked planets on circular orbits will rotate synchronously, but those on eccentric orbits will either librate or rotate super-synchronously. Although these features of tidal theory are well known, a systematic survey of the rotational evolution of potentially habitable exoplanets using classic equilibrium tide theories has not been undertaken. I calculate how habitable planets evolve under two commonly used models and find, for example, that one model predicts that the Earth's rotation rate would have synchronized after 4.5 Gyr if its initial rotation period was 3 days, it had no satellites, and it always maintained the modern Earth's tidal properties. Lower mass stellar hosts will induce stronger tidal effects on potentially habitable planets, and tidal locking is possible for most planets in the habitable zones of GKM dwarf stars. For fast-rotating planets, both models predict eccentricity growth and that circularization can only occur once the rotational frequency is similar to the orbital frequency. The orbits of potentially habitable planets of very late M dwarfs ([InlineEquation not available: see fulltext.]) are very likely to be circularized within 1 Gyr, and hence, those planets will be synchronous rotators. Proxima b is almost assuredly tidally locked, but its orbit may not have circularized yet, so the planet could be rotating super-synchronously today. The evolution of the isolated and potentially habitable Kepler planet candidates is computed and about half could be tidally locked. Finally, projected TESS planets

  6. 49 CFR 236.766 - Locking, movable bridge.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Locking, movable bridge. 236.766 Section 236.766... Locking, movable bridge. The rail locks, bridge locks, bolt locks, circuit controllers, and electric locks used in providing interlocking protection at a movable bridge. ...

  7. Ship maneuvering digital simulator; Simulador digital de manobras de navios

    Energy Technology Data Exchange (ETDEWEB)

    Souza Junior, Jesse Rebello; Tannuri, Eduardo Aoun; Oshiro, Anderson Takehiro [Universidade de Sao Paulo (USP), SP (Brazil). Escola Politecnica. Dept. de Engenharia Naval e Oceanica

    2008-07-01

    This paper reports on two case studies making use of a digital simulator to investigate the maneuvering motions of ships in canals with shallow and restricted waters. The first case study corresponds to a maneuvering analysis conducted for the Port of Rio Grande (RS - Brazil), whose aim was to assess the potential impact upon maneuvers of the presence of a large offshore platform (the PETROBRAS P-53) which is to remain docked for several months at the Port to complete its construction. The second study made use of the simulator to evaluate the maneuvering conditions along the approach route and maneuvering basin of the Port of Ponta do Felix (PR - Brazil). The simulator includes a complete mathematical model of the ship dynamics in the horizontal plane when subjected to wind and current forces. It also comprises detailed models for the action of thrusters and propellers, both fixed and azimuth, employed to control maneuvers and dynamically position ships, as well as rudders and tugboats. He models used by the simulator allow for the effects of shallow and restricted waters, including the increase in resistance and lateral forces, increase in additional mass and the appearance of lateral and vertical suction (squatting). The simulator is implemented via an interactive interface through which the user is able to apply control actions (rudder angle, main engine, thrusters and tugboats) in real time during maneuvers, thereby reproducing to some extent the action of a pilot. (author)

  8. Helicopter Pilot Performance for Discrete-maneuver Flight Tasks

    Science.gov (United States)

    Heffley, R. K.; Bourne, S. M.; Hindson, W. S.

    1984-01-01

    This paper describes a current study of several basic helicopter flight maneuvers. The data base consists of in-flight measurements from instrumented helicopters using experienced pilots. The analysis technique is simple enough to apply without automatic data processing, and the results can be used to build quantitative matah models of the flight task and some aspects of the pilot control strategy. In addition to describing the performance measurement technqiue, some results are presented which define the aggressiveness and amplitude of maneuvering for several lateral maneuvers including turns and sidesteps.

  9. Constellation Mission Operation Working Group: ESMO Maneuver Planning Process Review

    Science.gov (United States)

    Moyer, Eric

    2015-01-01

    The Earth Science Mission Operation (ESMO) Project created an Independent Review Board to review our Conjunction Risk evaluation process and Maneuver Planning Process to identify improvements that safely manages mission conjunction risks, maintains ground track science requirements, and minimizes overall hours expended on High Interest Events (HIE). The Review Board is evaluating the current maneuver process which requires support by multiple groups. In the past year, there have been several changes to the processes although many prior and new concerns exist. This presentation will discuss maneuver process reviews and Board comments, ESMO assessment and path foward, ESMO future plans, recent changes and concerns.

  10. Performance of arm locking in LISA

    International Nuclear Information System (INIS)

    McKenzie, Kirk; Spero, Robert E.; Shaddock, Daniel A.

    2009-01-01

    For the Laser Interferometer Space Antenna (LISA) to reach its design sensitivity, the coupling of the free-running laser frequency noise to the signal readout must be reduced by more than 14 orders of magnitude. One technique employed to reduce the laser frequency noise will be arm locking, where the laser frequency is locked to the LISA arm length. In this paper we detail an implementation of arm locking. We investigate orbital effects (changing arm lengths and Doppler frequencies), the impact of errors in the Doppler knowledge that can cause pulling of the laser frequency, and the noise limit of arm locking. Laser frequency pulling is examined in two regimes: at lock acquisition and in steady state. The noise performance of arm locking is calculated with the inclusion of the dominant expected noise sources: ultrastable oscillator (clock) noise, spacecraft motion, and shot noise. We find that clock noise and spacecraft motion limit the performance of dual arm locking in the LISA science band. Studying these issues reveals that although dual arm locking [A. Sutton and D. A. Shaddock, Phys. Rev. D 78, 082001 (2008)] has advantages over single (or common) arm locking in terms of allowing high gain, it has disadvantages in both laser frequency pulling and noise performance. We address this by proposing a modification to the dual arm-locking sensor, a hybrid of common and dual arm-locking sensors. This modified dual arm-locking sensor has the laser frequency pulling characteristics and low-frequency noise coupling of common arm locking, but retains the control system advantages of dual arm locking. We present a detailed design of an arm-locking controller and perform an analysis of the expected performance when used with and without laser prestabilization. We observe that the sensor phase changes beneficially near unity-gain frequencies of the arm-locking controller, allowing a factor of 10 more gain than previously believed, without degrading stability. With a time

  11. Is John Locke a democrat?

    DEFF Research Database (Denmark)

    Svensson, Palle

      Over recent years there has been a tendency to present John Locke as an equalitarian democrat (Ashcraft) and being close to the political views of the levellers (Waldron). This is not a completely new interpretation (Kendall, 1941), but contrasts with the prevalent view presented in textbooks (......, criteria for a democratic process, and the institutions of polyarchy. The conclusion has implications for the relationship between political liberalism and constitutionalism on the one hand and democracy on the other....

  12. Improvements to the adaptive maneuvering logic program

    Science.gov (United States)

    Burgin, George H.

    1986-01-01

    The Adaptive Maneuvering Logic (AML) computer program simulates close-in, one-on-one air-to-air combat between two fighter aircraft. Three important improvements are described. First, the previously available versions of AML were examined for their suitability as a baseline program. The selected program was then revised to eliminate some programming bugs which were uncovered over the years. A listing of this baseline program is included. Second, the equations governing the motion of the aircraft were completely revised. This resulted in a model with substantially higher fidelity than the original equations of motion provided. It also completely eliminated the over-the-top problem, which occurred in the older versions when the AML-driven aircraft attempted a vertical or near vertical loop. Third, the requirements for a versatile generic, yet realistic, aircraft model were studied and implemented in the program. The report contains detailed tables which make the generic aircraft to be either a modern, high performance aircraft, an older high performance aircraft, or a previous generation jet fighter.

  13. Effects-Based Operations: The End of Dominant Maneuver?

    National Research Council Canada - National Science Library

    Cheek, Gary

    2002-01-01

    ... without dominant ground maneuver. The paper concludes that such thinking misreads a historical warfare lethality trend in a potentially dangerous effort to vindicate the Air Force doctrine of strategic attack...

  14. Close Proximity Robotic Maneuvering through Flux Pinning Manipulation

    Data.gov (United States)

    National Aeronautics and Space Administration — Non-contacting actuation technology like flux pinning has never been demonstrated in space. The development of a nonphysical joint is critical for maneuvers such as...

  15. Automated Precision Maneuvering and Landing in Extreme and Constrained Environments

    Data.gov (United States)

    National Aeronautics and Space Administration — Autonomous, precise maneuvering and landing in extreme and constrained environments is a key enabler for future NASA missions. Missions to map the interior of a...

  16. Tongue-Driven Wheelchair Out-Maneuvers the Competition

    Science.gov (United States)

    ... 2, 2014 Tongue-Driven Wheelchair Out-Maneuvers the Competition Researchers funded by the National Institute of Biomedical ... significant step towards vastly improving the independence and quality of life of individuals with tetraplegia, and is ...

  17. The mechanical benefit of medial support screws in locking plating of proximal humerus fractures.

    Directory of Open Access Journals (Sweden)

    Wen Zhang

    Full Text Available BACKGROUND: The purpose of this study was to evaluate the biomechanical advantages of medial support screws (MSSs in the locking proximal humeral plate for treating proximal humerus fractures. METHODS: Thirty synthetic left humeri were randomly divided into 3 subgroups to establish two-part surgical neck fracture models of proximal humerus. All fractures were fixed with a locking proximal humerus plate. Group A was fixed with medial cortical support and no MSSs; Group B was fixed with 3 MSSs but without medial cortical support; Group C was fixed with neither medial cortical support nor MSSs. Axial compression, torsional stiffness, shear stiffness, and failure tests were performed. RESULTS: Constructs with medial support from cortical bone showed statistically higher axial and shear stiffness than other subgroups examined (P<0.0001. When the proximal humerus was not supported by medial cortical bone, locking plating with medial support screws exhibited higher axial and torsional stiffness than locking plating without medial support screws (P ≤ 0.0207. Specimens with medial cortical bone failed primarily by fracture of the humeral shaft or humeral head. Specimens without medial cortical bone support failed primarily by significant plate bending at the fracture site followed by humeral head collapse or humeral head fracture. CONCLUSIONS: Anatomic reduction with medial cortical support was the stiffest construct after a simulated two-part fracture. Significant biomechanical benefits of MSSs in locking plating of proximal humerus fractures were identified. The reconstruction of the medial column support for proximal humerus fractures helps to enhance mechanical stability of the humeral head and prevent implant failure.

  18. Phase-locked Josephson soliton oscillators

    DEFF Research Database (Denmark)

    Holst, T.; Hansen, Jørn Bindslev; Grønbech-Jensen, N.

    1991-01-01

    Detailed experimental characterization of the phase-locking at both DC and at microwave frequencies is presented for two closely spaced Josephson soliton (fluxon) oscillators. In the phase-locked state, the radiated microwave power exhibited an effective gain. With one common bias source......, a frequency tunability of the phase-locked oscillators up to 7% at 10 GHz was observed. The interacting soliton oscillators were modeled by two inductively coupled nonlinear transmission lines...

  19. Microcontroller-based locking in optics experiments

    International Nuclear Information System (INIS)

    Huang, K.; Le Jeannic, H.; Ruaudel, J.; Morin, O.; Laurat, J.

    2014-01-01

    Optics experiments critically require the stable and accurate locking of relative phases between light beams or the stabilization of Fabry-Perot cavity lengths. Here, we present a simple and inexpensive technique based on a stand-alone microcontroller unit to perform such tasks. Easily programmed in C language, this reconfigurable digital locking system also enables automatic relocking and sequential functioning. Different algorithms are detailed and applied to fringe locking and to low- and high-finesse optical cavity stabilization, without the need of external modulations or error signals. This technique can readily replace a number of analog locking systems advantageously in a variety of optical experiments

  20. Safety lock for radiography exposure device

    International Nuclear Information System (INIS)

    Gaines, T.M.

    1982-01-01

    A safety lock for securing a radiation source in a radiography exposure device is disclosed. The safety lock prevents the inadvertent extension of the radiation source from the exposure device. The exposure devices are used extensively in industry for nondestructive testing of metal materials for defect. Unnecessary exposure of the radiographer or operator occurs not infrequently due to operator's error in believing that the radiation source is secured in the exposure device when, in fact, it is not. The present invention solves this problem of unnecessary exposure by releasingly trapping the radiation source in the shield of the radiography exposure device each time the source is retracted therein so that it is not inadvertently extended therefrom without the operator resetting the safety lock, thereby releasing the radiation source. Further, the safety lock includes an indicator which indicates when the source is trapped in the exposure device and also when it is untrapped. The safety lock is so designed that it does not prevent the return of the source to the trapped, shielded position in the exposure device. Further the safety lock includes a key means for locking the radiation source in the trapped position. The key means cannot be actuated until said radiation source is in said trapped position to further insure the safety lock cannot be inadvertently locked with the source untrapped and thus still extendable from the exposure device

  1. Phase locking between Josephson soliton oscillators

    DEFF Research Database (Denmark)

    Holst, T.; Hansen, Jørn Bindslev; Grønbech-Jensen, N.

    1990-01-01

    We report observations of phase-locking phenomena between two Josephson soliton (fluxon) oscillators biased in self-resonant modes. The locking strength was measured as a function of bias conditions. A frequency tunability of the phase-locked oscillators up to 7% at 10 GHz was observed. Two coupled...... perturbed sine-Gordon equations were derived from an equivalent circuit consisting of inductively coupled, nonlinear, lossy transmission lines. These equations were solved numerically to find the locking regions. Good qualitative agreement was found between the experimental results and the calculations...

  2. Microcontroller-based locking in optics experiments.

    Science.gov (United States)

    Huang, K; Le Jeannic, H; Ruaudel, J; Morin, O; Laurat, J

    2014-12-01

    Optics experiments critically require the stable and accurate locking of relative phases between light beams or the stabilization of Fabry-Perot cavity lengths. Here, we present a simple and inexpensive technique based on a stand-alone microcontroller unit to perform such tasks. Easily programmed in C language, this reconfigurable digital locking system also enables automatic relocking and sequential functioning. Different algorithms are detailed and applied to fringe locking and to low- and high-finesse optical cavity stabilization, without the need of external modulations or error signals. This technique can readily replace a number of analog locking systems advantageously in a variety of optical experiments.

  3. Microcontroller-based locking in optics experiments

    Energy Technology Data Exchange (ETDEWEB)

    Huang, K. [Laboratoire Kastler Brossel, UPMC-Sorbonne Universités, CNRS, ENS-PSL Research University, Collège de France, 4 place Jussieu, 75005 Paris (France); State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai 200062 (China); Le Jeannic, H.; Ruaudel, J.; Morin, O.; Laurat, J., E-mail: julien.laurat@upmc.fr [Laboratoire Kastler Brossel, UPMC-Sorbonne Universités, CNRS, ENS-PSL Research University, Collège de France, 4 place Jussieu, 75005 Paris (France)

    2014-12-15

    Optics experiments critically require the stable and accurate locking of relative phases between light beams or the stabilization of Fabry-Perot cavity lengths. Here, we present a simple and inexpensive technique based on a stand-alone microcontroller unit to perform such tasks. Easily programmed in C language, this reconfigurable digital locking system also enables automatic relocking and sequential functioning. Different algorithms are detailed and applied to fringe locking and to low- and high-finesse optical cavity stabilization, without the need of external modulations or error signals. This technique can readily replace a number of analog locking systems advantageously in a variety of optical experiments.

  4. Double pass locking and spatial mode locking for gravitational wave detectors

    CERN Document Server

    Cusack, B J; Slagmolen, B; Vine, G D; Gray, M B; McClelland, D E

    2002-01-01

    We present novel techniques for overcoming problems relating to the use of high-power lasers in mode cleaner cavities for second generation laser interferometric gravitational wave detectors. Rearranging the optical components into a double pass locking regime can help to protect locking detectors from damage. Modulator thermal lensing can be avoided by using a modulation-free technique such as tilt locking, or its recently developed cousin, flip locking.

  5. An overview of Suomi NPP VIIRS calibration maneuvers

    Science.gov (United States)

    Butler, James J.; Xiong, Xiaoxiong; Barnes, Robert A.; Patt, Frederick S.; Sun, Junqiang; Chiang, Kwofu

    2012-09-01

    The first Visible Infrared Imager Radiometer Suite (VIIRS) instrument was successfully launched on-board the Suomi National Polar-orbiting Partnership (SNPP) spacecraft on October 28, 2011. Suomi NPP VIIRS observations are made in 22 spectral bands, from the visible (VIS) to the long-wave infrared (LWIR), and are used to produce 22 Environmental Data Records (EDRs) with a broad range of scientific applications. The quality of these VIIRS EDRs strongly depends on the quality of its calibrated and geo-located Sensor Date Records (SDRs). Built with a strong heritage to the NASA's EOS MODerate resolution Imaging Spectroradiometer (MODIS) instrument, the VIIRS is calibrated on-orbit using a similar set of on-board calibrators (OBC), including a solar diffuser (SD) and solar diffuser stability monitor (SDSM) system for the reflective solar bands (RSB) and a blackbody (BB) for the thermal emissive bands (TEB). Onorbit maneuvers of the SNPP spacecraft provide additional calibration and characterization data from the VIIRS instrument which cannot be obtained pre-launch and are required to produce the highest quality SDRs. These include multiorbit yaw maneuvers for the characterization of SD and SDSM screen transmission, quasi-monthly roll maneuvers to acquire lunar observations to track sensor degradation in the visible through shortwave infrared, and a driven pitch-over maneuver to acquire multiple scans of deep space to determine TEB response versus scan angle (RVS). This paper provides an overview of these three SNPP calibration maneuvers. Discussions are focused on their potential calibration and science benefits, pre-launch planning activities, and on-orbit scheduling and implementation strategies. Results from calibration maneuvers performed during the Intensive Calibration and Validation (ICV) period for the VIIRS sensor are illustrated. Also presented in this paper are lessons learned regarding the implementation of calibration spacecraft maneuvers on follow

  6. Self locking drive system for rotating plug of a nuclear reactor

    International Nuclear Information System (INIS)

    Brubaker, J.E.

    1979-01-01

    A self locking drive system for rotating the plugs on the head of a nuclear reactor which is able to restrain plug motion if a seismic event whould occur during reactor refueling is described. A servomotor is engaged via a gear train and a bull gear to the plug. Connected to the gear train is a feedback control system which allows the motor to rotate the plug to predetermined locations for refueling of the reactor. The gear train contains a self locking double enveloping worm gear set. The worm gear set is utilized for its self locking nature to prevent unwanted rotation of the plugs as the result of an earthquake. The double enveloping type is used because its unique contour spreads the load across several teeth providing added strength and allowing the use of a conventional size worm

  7. Dynamic cerebral autoregulation changes during sub-maximal handgrip maneuver.

    Directory of Open Access Journals (Sweden)

    Ricardo C Nogueira

    Full Text Available PURPOSE: We investigated the effect of handgrip (HG maneuver on time-varying estimates of dynamic cerebral autoregulation (CA using the autoregressive moving average technique. METHODS: Twelve healthy subjects were recruited to perform HG maneuver during 3 minutes with 30% of maximum contraction force. Cerebral blood flow velocity, end-tidal CO₂ pressure (PETCO₂, and noninvasive arterial blood pressure (ABP were continuously recorded during baseline, HG and recovery. Critical closing pressure (CrCP, resistance area-product (RAP, and time-varying autoregulation index (ARI were obtained. RESULTS: PETCO₂ did not show significant changes during HG maneuver. Whilst ABP increased continuously during the maneuver, to 27% above its baseline value, CBFV raised to a plateau approximately 15% above baseline. This was sustained by a parallel increase in RAP, suggestive of myogenic vasoconstriction, and a reduction in CrCP that could be associated with metabolic vasodilation. The time-varying ARI index dropped at the beginning and end of the maneuver (p<0.005, which could be related to corresponding alert reactions or to different time constants of the myogenic, metabolic and/or neurogenic mechanisms. CONCLUSION: Changes in dynamic CA during HG suggest a complex interplay of regulatory mechanisms during static exercise that should be considered when assessing the determinants of cerebral blood flow and metabolism.

  8. Dynamic Cerebral Autoregulation Changes during Sub-Maximal Handgrip Maneuver

    Science.gov (United States)

    Nogueira, Ricardo C.; Bor-Seng-Shu, Edson; Santos, Marcelo R.; Negrão, Carlos E.; Teixeira, Manoel J.; Panerai, Ronney B.

    2013-01-01

    Purpose We investigated the effect of handgrip (HG) maneuver on time-varying estimates of dynamic cerebral autoregulation (CA) using the autoregressive moving average technique. Methods Twelve healthy subjects were recruited to perform HG maneuver during 3 minutes with 30% of maximum contraction force. Cerebral blood flow velocity, end-tidal CO2 pressure (PETCO2), and noninvasive arterial blood pressure (ABP) were continuously recorded during baseline, HG and recovery. Critical closing pressure (CrCP), resistance area-product (RAP), and time-varying autoregulation index (ARI) were obtained. Results PETCO2 did not show significant changes during HG maneuver. Whilst ABP increased continuously during the maneuver, to 27% above its baseline value, CBFV raised to a plateau approximately 15% above baseline. This was sustained by a parallel increase in RAP, suggestive of myogenic vasoconstriction, and a reduction in CrCP that could be associated with metabolic vasodilation. The time-varying ARI index dropped at the beginning and end of the maneuver (p<0.005), which could be related to corresponding alert reactions or to different time constants of the myogenic, metabolic and/or neurogenic mechanisms. Conclusion Changes in dynamic CA during HG suggest a complex interplay of regulatory mechanisms during static exercise that should be considered when assessing the determinants of cerebral blood flow and metabolism. PMID:23967113

  9. Unusual inferior dislocation of shoulder: reduction by two-step maneuver: a case report

    Directory of Open Access Journals (Sweden)

    Patro Dilip K

    2009-11-01

    Full Text Available Abstract Dislocation of the shoulder is the commonest of all large joint dislocations. Inferior dislocation constitutes 0.5% of all shoulder dislocations. It characteristically presents with overhead abduction of the arm, the humerus being parallel to the spine of scapula. We present an unusual case of recurrent luxatio erecta in which the arm transformed later into an adducted position resembling the more common anterior shoulder dislocation. Such a case has not been described before in English literature. Closed reduction by the two-step maneuver was successful with a single attempt. MRI revealed posterior labral tear and a Hill-Sachs variant lesion on the superolateral aspect of humeral head. Immobilisation in a chest-arm bandage followed by physiotherapy yielded excellent results. The case is first of its kind; the unusual mechanism, unique radiological findings and alternate method of treatment are discussed.

  10. Comparing the Overhead of Lock-based and Lock-free Implementations of Priority Queues

    DEFF Research Database (Denmark)

    Passas, Stavros; Karlsson, Sven

    2011-01-01

    . In this paper, we compare a lock-free implementation of a priority queue with a lock-based implementation. We perform experiments with processors of different generations and observe large performance differences for lock-free data structures depending on the processor generation. The lock-free implementation...... performs much better on the most recent processor generation. We investigate this performance trend, using a set of micro-benchmarks and show a significant difference in the overhead of atomic operations between processor generations. The lock-free implementation executes approximately three times as many...

  11. Past, Present, Future Erosion at Locke Island

    Energy Technology Data Exchange (ETDEWEB)

    Bjornstad, Bruce N.

    2006-08-08

    This report describes and documents the erosion that has occurred along the northeast side of Locke Island over the last 10 to 20 years. The principal cause of this erosion is the massive Locke Island landslide complex opposite the Columbia River along the White Bluffs, which constricts the flow of the river and deflects the river's thalweg southward against the island.

  12. Head Lice

    Science.gov (United States)

    ... nits. You should also use hot water to wash any bed linens, towels, and clothing recently worn by the person who had head lice. Vacuum anything that can’t be washed, such as the couch, carpets, your child’s car seat, and any stuffed animals. Because head lice ...

  13. An automatic mode-locked system for passively mode-locked fiber laser

    Science.gov (United States)

    Li, Sha; Xu, Jun; Chen, Guoliang; Mei, Li; Yi, Bo

    2013-12-01

    This paper designs and implements one kind of automatic mode-locked system. It can adjust a passively mode-locked fiber laser to keep steady mode-locked states automatically. So the unsteadiness of traditional passively mode-locked fiber laser can be avoided. The system transforms optical signals into electrical pulse signals and sends them into MCU after processing. MCU calculates the frequency of the signals and judges the state of the output based on a quick judgment algorithm. A high-speed comparator is used to check the signals and the comparison voltage can be adjusted to improve the measuring accuracy. Then by controlling two polarization controllers at an angle of 45degrees to each other, MCU extrudes the optical fibers to change the polarization until it gets proper mode-locked output. So the system can continuously monitor the output signal and get it back to mode-locked states quickly and automatically. States of the system can be displayed on the LCD and PC. The parameters of the steady mode-locked states can be stored into an EEPROM so that the system will get into mode-locked states immediately next time. Actual experiments showed that, for a 6.238MHz passively mode-locked fiber lasers, the system can get into steady mode-locked states automatically in less than 90s after starting the system. The expected lock time can be reduced to less than 20s after follow up improvements.

  14. Nuclear reactor incorporating locking device for threaded bolt connections

    International Nuclear Information System (INIS)

    Blaushild, R.M.

    1987-01-01

    A nuclear reactor having a pressure vessel and a first element is described comprising a core barrel situated within the pressure vessel. The core barrel has a baffle former secured in and to the core barrel by bolted connections, and a second element comprising baffle plates secured to the inner surface of the baffle former by bolted connections, with a locking device to prevent loosening of bolted connections between the baffle former and at least one of the elements. The baffle former and at least one element are held together by a headed, threaded bolt engaged in a bore coaxially extending in the baffle former and at least one element and threadedly engaged in a threaded section in at least the baffle former. The threaded section has first threaded of a first direction, with the head of the bolt engaged with a shoulder about the bore in at least one element to hold the baffle formed and at least one element together, the head of the bolt having a first diameter and a cavity, having an unsymmetrical wall thereabout, in the end surface thereof. It comprises a recess in at least one element coaxial with the bore forming a wall thereabout and extending inwardly from the outer surface of at least one element, the recess having a second diameter greater than the first diameter, with at least one element having second threads in the wall of a direction opposite the direction of the first threads of the threaded bore; a locking nut having a base with a downwardly depending cylindrical wall thereabout

  15. Commonwealth Edison Company pressure locking test report

    Energy Technology Data Exchange (ETDEWEB)

    Bunte, B.D.; Kelly, J.F.

    1996-12-01

    Pressure Locking is a phenomena which can cause the unseating thrust for a gate valve to increase dramatically from its typical static unseating thrust. This can result in the valve actuator having insufficient capability to open the valve. In addition, this can result in valve damage in cases where the actuator capability exceeds the valve structural limits. For these reasons, a proper understanding of the conditions which may cause pressure locking and thermal binding, as well as a methodology for predicting the unseating thrust for a pressure locked or thermally bound valve, are necessary. This report discusses the primary mechanisms which cause pressure locking. These include sudden depressurization of piping adjacent to the valve and pressurization of fluid trapped in the valve bonnet due to heat transfer. This report provides a methodology for calculating the unseating thrust for a valve which is pressure locked. This report provides test data which demonstrates the accuracy of the calculation methodology.

  16. Commonwealth Edison Company pressure locking test report

    International Nuclear Information System (INIS)

    Bunte, B.D.; Kelly, J.F.

    1996-01-01

    Pressure Locking is a phenomena which can cause the unseating thrust for a gate valve to increase dramatically from its typical static unseating thrust. This can result in the valve actuator having insufficient capability to open the valve. In addition, this can result in valve damage in cases where the actuator capability exceeds the valve structural limits. For these reasons, a proper understanding of the conditions which may cause pressure locking and thermal binding, as well as a methodology for predicting the unseating thrust for a pressure locked or thermally bound valve, are necessary. This report discusses the primary mechanisms which cause pressure locking. These include sudden depressurization of piping adjacent to the valve and pressurization of fluid trapped in the valve bonnet due to heat transfer. This report provides a methodology for calculating the unseating thrust for a valve which is pressure locked. This report provides test data which demonstrates the accuracy of the calculation methodology

  17. On spacecraft maneuvers control subject to propellant engine modes.

    Science.gov (United States)

    Mazinan, A H

    2015-09-01

    The paper attempts to address a new control approach to spacecraft maneuvers based upon the modes of propellant engine. A realization of control strategy is now presented in engine on mode (high thrusts as well as further low thrusts), which is related to small angle maneuvers and engine off mode (specified low thrusts), which is also related to large angle maneuvers. There is currently a coarse-fine tuning in engine on mode. It is shown that the process of handling the angular velocities are finalized via rate feedback system in engine modes, where the angular rotations are controlled through quaternion based control (QBCL)strategy in engine off mode and these ones are also controlled through an optimum PID (OPIDH) strategy in engine on mode. Copyright © 2015 ISA. Published by Elsevier Ltd. All rights reserved.

  18. A Maneuvering Flight Noise Model for Helicopter Mission Planning

    Science.gov (United States)

    Greenwood, Eric; Rau, Robert; May, Benjamin; Hobbs, Christopher

    2015-01-01

    A new model for estimating the noise radiation during maneuvering flight is developed in this paper. The model applies the Quasi-Static Acoustic Mapping (Q-SAM) method to a database of acoustic spheres generated using the Fundamental Rotorcraft Acoustics Modeling from Experiments (FRAME) technique. A method is developed to generate a realistic flight trajectory from a limited set of waypoints and is used to calculate the quasi-static operating condition and corresponding acoustic sphere for the vehicle throughout the maneuver. By using a previously computed database of acoustic spheres, the acoustic impact of proposed helicopter operations can be rapidly predicted for use in mission-planning. The resulting FRAME-QS model is applied to near-horizon noise measurements collected for the Bell 430 helicopter undergoing transient pitch up and roll maneuvers, with good agreement between the measured data and the FRAME-QS model.

  19. Morphology, muscle capacity, skill, and maneuvering ability in hummingbirds.

    Science.gov (United States)

    Dakin, Roslyn; Segre, Paolo S; Straw, Andrew D; Altshuler, Douglas L

    2018-02-09

    How does agility evolve? This question is challenging because natural movement has many degrees of freedom and can be influenced by multiple traits. We used computer vision to record thousands of translations, rotations, and turns from more than 200 hummingbirds from 25 species, revealing that distinct performance metrics are correlated and that species diverge in their maneuvering style. Our analysis demonstrates that the enhanced maneuverability of larger species is explained by their proportionately greater muscle capacity and lower wing loading. Fast acceleration maneuvers evolve by recruiting changes in muscle capacity, whereas fast rotations and sharp turns evolve by recruiting changes in wing morphology. Both species and individuals use turns that play to their strengths. These results demonstrate how both skill and biomechanical traits shape maneuvering behavior. Copyright © 2018 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.

  20. Maneuver Planning for Conjunction Risk Mitigation with Ground-track Control Requirements

    Science.gov (United States)

    McKinley, David

    2008-01-01

    The planning of conjunction Risk Mitigation Maneuvers (RMM) in the presence of ground-track control requirements is analyzed. Past RMM planning efforts on the Aqua, Aura, and Terra spacecraft have demonstrated that only small maneuvers are available when ground-track control requirements are maintained. Assuming small maneuvers, analytical expressions for the effect of a given maneuver on conjunction geometry are derived. The analytical expressions are used to generate a large trade space for initial RMM design. This trade space represents a significant improvement in initial maneuver planning over existing methods that employ high fidelity maneuver models and propagation.

  1. Neglected locked vertical patellar dislocation

    Science.gov (United States)

    Gupta, Rakesh Kumar; Gupta, Vinay; Sangwan, Sukhbir Singh; Kamboj, Pradeep

    2012-01-01

    Patellar dislocations occurring about the vertical and horizontal axis are rare and irreducible. The neglected patellar dislocation is still rarer. We describe the clinical presentation and management of a case of neglected vertical patellar dislocation in a 6 year-old boy who sustained an external rotational strain with a laterally directed force to his knee. Initially the diagnosis was missed and 2 months later open reduction was done. The increased tension generated by the rotation of the lateral extensor retinaculum kept the patella locked in the lateral gutter even with the knee in full extension. Traumatic patellar dislocation with rotation around a vertical axis has been described earlier, but no such neglected case has been reported to the best of our knowledge. PMID:23162154

  2. Neglected locked vertical patellar dislocation

    Directory of Open Access Journals (Sweden)

    Rakesh Kumar Gupta

    2012-01-01

    Full Text Available Patellar dislocations occurring about the vertical and horizontal axis are rare and irreducible. The neglected patellar dislocation is still rarer. We describe the clinical presentation and management of a case of neglected vertical patellar dislocation in a 6 year-old boy who sustained an external rotational strain with a laterally directed force to his knee. Initially the diagnosis was missed and 2 months later open reduction was done. The increased tension generated by the rotation of the lateral extensor retinaculum kept the patella locked in the lateral gutter even with the knee in full extension. Traumatic patellar dislocation with rotation around a vertical axis has been described earlier, but no such neglected case has been reported to the best of our knowledge.

  3. Unusual Cause of Knee Locking

    Directory of Open Access Journals (Sweden)

    Gazi Huri

    2013-01-01

    Full Text Available We report a case of partial intrasubstance tear of popliteus tendon as an unusual cause of pseudolocking of the knee. A 13-year-old semiprofessional soccer player applied to our clinic with a locked right knee in spite of the therapy applied (cold pack, NSAID, and immobilization in another institution 20 days after the injury. Significant extension loss was observed in his right knee with 30∘–90∘ ROM. Magnetic resonance imaging (MRI and arthroscopy confirmed the intrasubstance tear of popliteus tendon and synovitis. The ruptured part of the tendon was debrided, and the inflammatory tissue around the tendon, which may lead to pseudolocking, was gently removed with a shaver in order to regain the normal ROM. The patient was discharged with full ROM and weight bearing first day after the surgery. To our knowledge, this is the first case demonstrating intrasubstance tear of popliteus tendon causing pseudolocking of the knee.

  4. Maneuver Acoustic Flight Test of the Bell 430 Helicopter

    Science.gov (United States)

    Watts, Michael E.; Snider, Royce; Greenwood, Eric; Baden, Joel

    2012-01-01

    A cooperative flight test by NASA, Bell Helicopter and the U.S. Army to characterize the steady state acoustics and measure the maneuver noise of a Bell Helicopter 430 aircraft was accomplished. The test occurred during June/July, 2011 at Eglin Air Force Base, Florida. This test gathered a total of 410 data points over 10 test days and compiled an extensive data base of dynamic maneuver measurements. Three microphone configurations with up to 31 microphones in each configuration were used to acquire acoustic data. Aircraft data included DGPS, aircraft state and rotor state information. This paper provides an overview of the test.

  5. Space Objects Maneuvering Detection and Prediction via Inverse Reinforcement Learning

    Science.gov (United States)

    Linares, R.; Furfaro, R.

    This paper determines the behavior of Space Objects (SOs) using inverse Reinforcement Learning (RL) to estimate the reward function that each SO is using for control. The approach discussed in this work can be used to analyze maneuvering of SOs from observational data. The inverse RL problem is solved using the Feature Matching approach. This approach determines the optimal reward function that a SO is using while maneuvering by assuming that the observed trajectories are optimal with respect to the SO's own reward function. This paper uses estimated orbital elements data to determine the behavior of SOs in a data-driven fashion.

  6. Virtual simulation of maneuvering captive tests for a surface vessel

    Directory of Open Access Journals (Sweden)

    Ahmad Hajivand

    2015-09-01

    Full Text Available Hydrodynamic derivatives or coefficients are required to predict the maneuvering characteristics of a marine vehicle. These derivatives are obtained numerically for a DTMB 5512 model ship by virtual simulating of captive model tests in a CFD environment. The computed coefficients are applied to predict the turning circle and zigzag maneuvers of the model ship. The comparison of the simulated results with the available experimental data shows a very good agreement among them. The simulations show that the CFD is precise and affordable tool at the preliminary design stage to obtain maneuverability performance of a marine vehicles.

  7. No Snowball on Habitable Tidally Locked Planets

    Science.gov (United States)

    Checlair, Jade; Menou, Kristen; Abbot, Dorian S.

    2017-08-01

    The TRAPPIST-1, Proxima Centauri, and LHS 1140 systems are the most exciting prospects for future follow-up observations of potentially inhabited planets. All of the planets orbit nearby M-stars and are likely tidally locked in 1:1 spin–orbit states, which motivates the consideration of the effects that tidal locking might have on planetary habitability. On Earth, periods of global glaciation (snowballs) may have been essential for habitability and remote signs of life (biosignatures) because they are correlated with increases in the complexity of life and in the atmospheric oxygen concentration. In this paper, we investigate the snowball bifurcation (sudden onset of global glaciation) on tidally locked planets using both an energy balance model and an intermediate-complexity global climate model. We show that tidally locked planets are unlikely to exhibit a snowball bifurcation as a direct result of the spatial pattern of insolation they receive. Instead, they will smoothly transition from partial to complete ice coverage and back. A major implication of this work is that tidally locked planets with an active carbon cycle should not be found in a snowball state. Moreover, this work implies that tidally locked planets near the outer edge of the habitable zone with low CO2 outgassing fluxes will equilibrate with a small unglaciated substellar region rather than cycling between warm and snowball states. More work is needed to determine how the lack of a snowball bifurcation might affect the development of life on a tidally locked planet.

  8. No Snowball on Habitable Tidally Locked Planets

    Energy Technology Data Exchange (ETDEWEB)

    Checlair, Jade; Abbot, Dorian S. [Department of the Geophysical Sciences, University of Chicago, 5734 South Ellis Avenue, Chicago, IL 60637 (United States); Menou, Kristen, E-mail: jadecheclair@uchicago.edu [Centre for Planetary Sciences, Department of Physical and Environmental Sciences, University of Toronto at Scarborough, Toronto, ON M1C 1A4 (Canada)

    2017-08-20

    The TRAPPIST-1, Proxima Centauri, and LHS 1140 systems are the most exciting prospects for future follow-up observations of potentially inhabited planets. All of the planets orbit nearby M-stars and are likely tidally locked in 1:1 spin–orbit states, which motivates the consideration of the effects that tidal locking might have on planetary habitability. On Earth, periods of global glaciation (snowballs) may have been essential for habitability and remote signs of life (biosignatures) because they are correlated with increases in the complexity of life and in the atmospheric oxygen concentration. In this paper, we investigate the snowball bifurcation (sudden onset of global glaciation) on tidally locked planets using both an energy balance model and an intermediate-complexity global climate model. We show that tidally locked planets are unlikely to exhibit a snowball bifurcation as a direct result of the spatial pattern of insolation they receive. Instead, they will smoothly transition from partial to complete ice coverage and back. A major implication of this work is that tidally locked planets with an active carbon cycle should not be found in a snowball state. Moreover, this work implies that tidally locked planets near the outer edge of the habitable zone with low CO{sub 2} outgassing fluxes will equilibrate with a small unglaciated substellar region rather than cycling between warm and snowball states. More work is needed to determine how the lack of a snowball bifurcation might affect the development of life on a tidally locked planet.

  9. No Snowball on Habitable Tidally Locked Planets

    International Nuclear Information System (INIS)

    Checlair, Jade; Abbot, Dorian S.; Menou, Kristen

    2017-01-01

    The TRAPPIST-1, Proxima Centauri, and LHS 1140 systems are the most exciting prospects for future follow-up observations of potentially inhabited planets. All of the planets orbit nearby M-stars and are likely tidally locked in 1:1 spin–orbit states, which motivates the consideration of the effects that tidal locking might have on planetary habitability. On Earth, periods of global glaciation (snowballs) may have been essential for habitability and remote signs of life (biosignatures) because they are correlated with increases in the complexity of life and in the atmospheric oxygen concentration. In this paper, we investigate the snowball bifurcation (sudden onset of global glaciation) on tidally locked planets using both an energy balance model and an intermediate-complexity global climate model. We show that tidally locked planets are unlikely to exhibit a snowball bifurcation as a direct result of the spatial pattern of insolation they receive. Instead, they will smoothly transition from partial to complete ice coverage and back. A major implication of this work is that tidally locked planets with an active carbon cycle should not be found in a snowball state. Moreover, this work implies that tidally locked planets near the outer edge of the habitable zone with low CO 2 outgassing fluxes will equilibrate with a small unglaciated substellar region rather than cycling between warm and snowball states. More work is needed to determine how the lack of a snowball bifurcation might affect the development of life on a tidally locked planet.

  10. Head Injuries

    Science.gov (United States)

    ... a severe blow to the head can still knock the brain into the side of the skull ... following certain precautions and taking a break from sports and other activities that make symptoms worse. Playing ...

  11. Correlations between locked modes and impurity influxes

    Energy Technology Data Exchange (ETDEWEB)

    Fishpool, G M [Commission of the European Communities, Abingdon (United Kingdom). JET Joint Undertaking; Lawson, K D [UKAEA Culham Lab., Abingdon (United Kingdom)

    1994-07-01

    An analysis of pulses that were disturbed by medium Z impurity influxes (Cl, Cr, Fe and Ni) recorded during the 91/92 JET operations, has demonstrated that such influxes can result in MHD modes which subsequently ``lock``. A correlation is found between the power radiated by the influx and the time difference between the start of the influx and the beginning of the locked mode. The growth in the amplitude of the locked mode itself can lead to further impurity influxes. A correlation is noted between intense influxes (superior to 10 MW) and the mode ``unlocking``. (authors). 4 refs., 4 figs.

  12. Transient Structured Distance as a Maneuver in Marital Therapy

    Science.gov (United States)

    Greene, Bernard L.; And Others

    1973-01-01

    Experience with 73 cases has shown the value of Transient Structured Distance as a maneuver in marriage therapy. While the TSD is a radical form of intervention with risks of anxiety reactions, homosexual panic, or divorce, it has proved effective with difficult forms of acute or chronic marital disharmony. (Author)

  13. 47 CFR 25.282 - Orbit raising maneuvers.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 2 2010-10-01 2010-10-01 false Orbit raising maneuvers. 25.282 Section 25.282 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES SATELLITE COMMUNICATIONS... geostationary satellite orbit under this part is also authorized to transmit in connection with short-term...

  14. A Small State Maneuvering in the Changing World Order

    DEFF Research Database (Denmark)

    Sørensen, Camilla T. N.

    2016-01-01

    , especially the Danish approach to the BRICs, has developed in recent years, I show how Denmark – a small state – is trying to maneuver in the changing world order through a “creative agency” approach characterized by pragmatic low-profile activism. I develop a neoclassical realist framework and use...

  15. Arm locking with Doppler estimation errors

    Energy Technology Data Exchange (ETDEWEB)

    Yu Yinan; Wand, Vinzenz; Mitryk, Shawn; Mueller, Guido, E-mail: yinan@phys.ufl.ed [Department of Physics, University of Florida, Gainesville, FL 32611 (United States)

    2010-05-01

    At the University of Florida we developed the University of Florida LISA Interferometer Simulator (UFLIS) in order to study LISA interferometry with hardware in the loop at a system level. One of the proposed laser frequency stabilization techniques in LISA is arm locking. Arm locking uses an adequately filtered linear combination of the LISA arm signals as a frequency reference. We will report about experiments in which we demonstrated arm locking using UFLIS. During these experiments we also discovered a problem associated with the Doppler shift of the return beam. The initial arm locking publications assumed that this Doppler shift can perfectly be subtracted inside the phasemeter or adds an insignificant offset to the sensor signal. However, the remaining Doppler knowledge error will cause a constant change in the laser frequency if unaccounted for. Several ways to circumvent this problem have been identified. We performed detailed simulations and started preliminary experiments to verify the performance of the proposed new controller designs.

  16. Optical double-locked semiconductor lasers

    Science.gov (United States)

    AlMulla, Mohammad

    2018-06-01

    Self-sustained period-one (P1) nonlinear dynamics of a semiconductor laser are investigated when both optical injection and modulation are applied for stable microwave frequency generation. Locking the P1 oscillation through modulation on the bias current, injection strength, or detuning frequency stabilizes the P1 oscillation. Through the phase noise variance, the different modulation types are compared. It is demonstrated that locking the P1 oscillation through optical modulation on the output of the master laser outperforms bias-current modulation of the slave laser. Master laser modulation shows wider P1-oscillation locking range and lower phase noise variance. The locking characteristics of the P1 oscillation also depend on the operating conditions of the optical injection system

  17. Improving generalized inverted index lock wait times

    Science.gov (United States)

    Borodin, A.; Mirvoda, S.; Porshnev, S.; Ponomareva, O.

    2018-01-01

    Concurrent operations on tree like data structures is a cornerstone of any database system. Concurrent operations intended for improving read\\write performance and usually implemented via some way of locking. Deadlock-free methods of concurrency control are known as tree locking protocols. These protocols provide basic operations(verbs) and algorithm (ways of operation invocations) for applying it to any tree-like data structure. These algorithms operate on data, managed by storage engine which are very different among RDBMS implementations. In this paper, we discuss tree locking protocol implementation for General inverted index (Gin) applied to multiversion concurrency control (MVCC) storage engine inside PostgreSQL RDBMS. After that we introduce improvements to locking protocol and provide usage statistics about evaluation of our improvement in very high load environment in one of the world’s largest IT company.

  18. Automatic NMR field-frequency lock-pulsed phase locked loop approach.

    Science.gov (United States)

    Kan, S; Gonord, P; Fan, M; Sauzade, M; Courtieu, J

    1978-06-01

    A self-contained deuterium frequency-field lock scheme for a high-resolution NMR spectrometer is described. It is based on phase locked loop techniques in which the free induction decay signal behaves as a voltage-controlled oscillator. By pulsing the spins at an offset frequency of a few hundred hertz and using a digital phase-frequency discriminator this method not only eliminates the usual phase, rf power, offset adjustments needed in conventional lock systems but also possesses the automatic pull-in characteristics that dispense with the use of field sweeps to locate the NMR line prior to closure of the lock loop.

  19. Interband optical pulse injection locking of quantum dot mode-locked semiconductor laser.

    Science.gov (United States)

    Kim, Jimyung; Delfyett, Peter J

    2008-07-21

    We experimentally demonstrate optical clock recovery from quantum dot mode-locked semiconductor lasers by interband optical pulse injection locking. The passively mode-locked slave laser oscillating on the ground state or the first excited state transition is locked through the injection of optical pulses generated via the opposite transition bands, i.e. the first excited state or the ground state transition from the hybridly mode-locked master laser, respectively. When an optical pulse train generated via the first excited state from the master laser is injected to the slave laser oscillating via ground state, the slave laser shows an asymmetric locking bandwidth around the nominal repetition rate of the slave laser. In the reverse injection case of, i.e. the ground state (master laser) to the first excited state (slave laser), the slave laser does not lock even though both lasers oscillate at the same cavity frequency. In this case, the slave laser only locks to higher injection rates as compared to its own nominal repetition rate, and also shows a large locking bandwidth of 6.7 MHz.

  20. Heading Estimation of Robot Combine Harvesters during Turning Maneuveres

    Directory of Open Access Journals (Sweden)

    Md Mostafizar Rahman

    2018-05-01

    Full Text Available Absolute heading is an important parameter for a robot combine harvester or a robot tracked combine harvester, especially while it is turning, but due to the rapid turning of robot combine harvesters, its inertial measurement unit gives a gyro measurement bias that causes heading drift. Our research goal is to estimate the absolute heading of robot combine harvesters by compensating this gyro measurement bias during non-linear turning maneuvers. A sensor fusion method like the extended Kalman filter combined with the tracked combine harvester dynamic model and sensor measurements was used to estimate the absolute heading of a robot combine harvester. Circular, sinusoidal and concave shapes were used to evaluate the estimated heading produced by the sensor fusion method. The results indicate that the estimated heading is better than measured heading which was calculated from the integration of yaw rate gyro measurements, and the root mean square errors (RMSEs for estimated headings are smaller than the measured headings. In practics, the target of this paper is thus the estimation of a heading or absolute heading that is bias compensated, and can be further used to calculate the exact crop periphery for automatic path planning of robot combine harvesters.

  1. Heading Estimation of Robot Combine Harvesters during Turning Maneuveres.

    Science.gov (United States)

    Rahman, Md Mostafizar; Ishii, Kazunobu

    2018-05-01

    Absolute heading is an important parameter for a robot combine harvester or a robot tracked combine harvester, especially while it is turning, but due to the rapid turning of robot combine harvesters, its inertial measurement unit gives a gyro measurement bias that causes heading drift. Our research goal is to estimate the absolute heading of robot combine harvesters by compensating this gyro measurement bias during non-linear turning maneuvers. A sensor fusion method like the extended Kalman filter combined with the tracked combine harvester dynamic model and sensor measurements was used to estimate the absolute heading of a robot combine harvester. Circular, sinusoidal and concave shapes were used to evaluate the estimated heading produced by the sensor fusion method. The results indicate that the estimated heading is better than measured heading which was calculated from the integration of yaw rate gyro measurements, and the root mean square errors (RMSEs) for estimated headings are smaller than the measured headings. In practics, the target of this paper is thus the estimation of a heading or absolute heading that is bias compensated, and can be further used to calculate the exact crop periphery for automatic path planning of robot combine harvesters.

  2. QPSK regeneration without active phase-locking

    DEFF Research Database (Denmark)

    Kjøller, Niels-Kristian; Da Ros, Francesco; Røge, Kasper Meldgaard

    2016-01-01

    QPSK regeneration without active phase stabilization is investigated in numerical simulations. We propose an improved scheme for phase-locking free QPSK regeneration showing significant improvements in the error vector magnitude of the signal.......QPSK regeneration without active phase stabilization is investigated in numerical simulations. We propose an improved scheme for phase-locking free QPSK regeneration showing significant improvements in the error vector magnitude of the signal....

  3. Automatic locking orthotic knee device

    Science.gov (United States)

    Weddendorf, Bruce C. (Inventor)

    1993-01-01

    An articulated tang in clevis joint for incorporation in newly manufactured conventional strap-on orthotic knee devices or for replacing such joints in conventional strap-on orthotic knee devices is discussed. The instant tang in clevis joint allows the user the freedom to extend and bend the knee normally when no load (weight) is applied to the knee and to automatically lock the knee when the user transfers weight to the knee, thus preventing a damaged knee from bending uncontrollably when weight is applied to the knee. The tang in clevis joint of the present invention includes first and second clevis plates, a tang assembly and a spacer plate secured between the clevis plates. Each clevis plate includes a bevelled serrated upper section. A bevelled shoe is secured to the tank in close proximity to the bevelled serrated upper section of the clevis plates. A coiled spring mounted within an oblong bore of the tang normally urges the shoes secured to the tang out of engagement with the serrated upper section of each clevic plate to allow rotation of the tang relative to the clevis plate. When weight is applied to the joint, the load compresses the coiled spring, the serrations on each clevis plate dig into the bevelled shoes secured to the tang to prevent relative movement between the tang and clevis plates. A shoulder is provided on the tang and the spacer plate to prevent overextension of the joint.

  4. Associating crash avoidance maneuvers with driver attributes and accident characteristics: a mixed logit model approach.

    Science.gov (United States)

    Kaplan, Sigal; Prato, Carlo Giacomo

    2012-01-01

    The current study focuses on the propensity of drivers to engage in crash avoidance maneuvers in relation to driver attributes, critical events, crash characteristics, vehicles involved, road characteristics, and environmental conditions. The importance of avoidance maneuvers derives from the key role of proactive and state-aware road users within the concept of sustainable safety systems, as well as from the key role of effective corrective maneuvers in the success of automated in-vehicle warning and driver assistance systems. The analysis is conducted by means of a mixed logit model that represents the selection among 5 emergency lateral and speed control maneuvers (i.e., "no avoidance maneuvers," "braking," "steering," "braking and steering," and "other maneuvers) while accommodating correlations across maneuvers and heteroscedasticity. Data for the analysis were retrieved from the General Estimates System (GES) crash database for the year 2009 by considering drivers for which crash avoidance maneuvers are known. The results show that (1) the nature of the critical event that made the crash imminent greatly influences the choice of crash avoidance maneuvers, (2) women and elderly have a relatively lower propensity to conduct crash avoidance maneuvers, (3) drowsiness and fatigue have a greater negative marginal effect on the tendency to engage in crash avoidance maneuvers than alcohol and drug consumption, (4) difficult road conditions increase the propensity to perform crash avoidance maneuvers, and (5) visual obstruction and artificial illumination decrease the probability to carry out crash avoidance maneuvers. The results emphasize the need for public awareness campaigns to promote safe driving style for senior drivers and warning about the risks of driving under fatigue and distraction being comparable to the risks of driving under the influence of alcohol and drugs. Moreover, the results suggest the need to educate drivers about hazard perception, designing

  5. How lovebirds maneuver rapidly using super-fast head saccades and image feature stabilization

    NARCIS (Netherlands)

    Kress, Daniel; Bokhorst, Van Evelien; Lentink, David

    2015-01-01

    Diurnal flying animals such as birds depend primarily on vision to coordinate their flight path during goal-directed flight tasks. To extract the spatial structure of the surrounding environment, birds are thought to use retinal image motion (optical flow) that is primarily induced by motion of

  6. Head Start.

    Science.gov (United States)

    Greenman, Geri

    2000-01-01

    Discusses an art project in which students created drawings of mop heads. Explains that the approach of drawing was more important than the subject. States that the students used the chiaroscuro technique, used by Rembrandt and Caravaggio, in which light appears out of the darkness. (CMK)

  7. Computation of the lock-in ranges of phase-locked loops with PI filter

    OpenAIRE

    Aleksandrov, Konstantin D.; Kuznetsov, Nikolay; Leonov, Gennady A.; Neittaanmäki, Pekka; Yuldashev, Marat V.; Yuldashev, Renat V.

    2016-01-01

    In the present work the lock-in range of PLL-based circuits with proportionallyintegrating filter and sinusoidal phase-detector characteristics are studied. Considered circuits have sinusoidal phase detector characteristics. Analytical approach based on the methods of phase plane analysis is applied to estimate the lock-in ranges of the circuits under consideration. Obtained analytical results are compared with simulation results.

  8. Monoaxial versus polyaxial locking systems: a biomechanical analysis of different locking systems for the fixation of proximal humeral fractures.

    Science.gov (United States)

    Zettl, Ralph; Müller, Thorben; Topp, Tobias; Lewan, Ulrike; Krüger, Antonio; Kühne, Christian; Ruchholtz, Steffen

    2011-08-01

    The development of locking plate systems has led to polyaxial screws and new plate designs. This study compares monoaxial head locking screws (PHILOS© by Synthes) and a new generation of polyaxial locking screws (NCB-LE© by Zimmer) with respect to biomechanical stability. On nine pairs of randomised formalin fixed humerus specimens, standardised osteotomies and osteosyntheses with nine monoaxial (group A) und nine polyaxial (group B) plate/screw systems were performed. A material testing machine by Instron (M-10 14961-DE) was used for cyclic stress tests and crash tests until defined breakup criteria as endpoints were reached. After axial cyclic stress 200 times at 90 N, plastic deformation was 1.02 mm in group A and 1.25 mm in group B. After the next cycle using 180 N the additional deformation averaged 0.23 mm in group A and 0.39 mm in group B. The deformation using 450 N was 0.72 mm in group A compared to 0.92 mm in group B. The final full power test resulted in a deformation average of 0.49 mm in group A and 0.63 mm in group B after 2,000 cycles using 450 N. When reaching the breakup criteria the plastic deformation of the NCB plate was 9.04 mm on average. The PHILOS plate was similarly deformed by 9.00 mm. As a result of the crash test, in group A the screws pulled out of the humeral head four times whereas the shaft broke one time and another time the implant was ripped out. The gap was closed four times. In group B, there were three cases of screw cut-through, four shaft fractures/screw avulsions from the shaft and two cases of gap closure. The two systems resist the cyclic duration tests and the increasing force tests in a similar manner. The considerable clinical benefits of the polyaxial system are enhanced by equal biomechanical performance.

  9. Evasive Maneuvers in Space Debris Environment and Technological Parameters

    Directory of Open Access Journals (Sweden)

    Antônio D. C. Jesus

    2012-01-01

    Full Text Available We present a study of collisional dynamics between space debris and an operational vehicle in LEO. We adopted an approach based on the relative dynamics between the objects on a collisional course and with a short warning time and established a semianalytical solution for the final trajectories of these objects. Our results show that there are angular ranges in 3D, in addition to the initial conditions, that favor the collisions. These results allowed the investigation of a range of technological parameters for the spacecraft (e.g., fuel reserve that allow a safe evasive maneuver (e.g., time available for the maneuver. The numerical model was tested for different values of the impact velocity and relative distance between the approaching objects.

  10. Thermally-Constrained Fuel-Optimal ISS Maneuvers

    Science.gov (United States)

    Bhatt, Sagar; Svecz, Andrew; Alaniz, Abran; Jang, Jiann-Woei; Nguyen, Louis; Spanos, Pol

    2015-01-01

    Optimal Propellant Maneuvers (OPMs) are now being used to rotate the International Space Station (ISS) and have saved hundreds of kilograms of propellant over the last two years. The savings are achieved by commanding the ISS to follow a pre-planned attitude trajectory optimized to take advantage of environmental torques. The trajectory is obtained by solving an optimal control problem. Prior to use on orbit, OPM trajectories are screened to ensure a static sun vector (SSV) does not occur during the maneuver. The SSV is an indicator that the ISS hardware temperatures may exceed thermal limits, causing damage to the components. In this paper, thermally-constrained fuel-optimal trajectories are presented that avoid an SSV and can be used throughout the year while still reducing propellant consumption significantly.

  11. Novel Fractional Order Calculus Extended PN for Maneuvering Targets

    Directory of Open Access Journals (Sweden)

    Jikun Ye

    2017-01-01

    Full Text Available Based on the theory of fractional order calculus (FOC, a novel extended proportional guidance (EPN law for intercepting the maneuvering target is proposed. In the first part, considering the memory function and filter characteristic of FOC, the novel extended PN guidance algorithm is developed based on the conventional PN after introducing the properties and operation rules of FOC. Further, with the help of FOC theory, the average load and ballistics characteristics of proposed guidance law are analyzed. Then, using the small offset kinematic model, the robustness of the new guidance law against autopilot parameters is studied theoretically by analyzing the sensitivity of the closed loop guidance system. At last, representative numerical results show that the designed guidance law obtains a better performance than the traditional PN for maneuvering target.

  12. Parametric Dependence of Initial LEV Behavior on Maneuvering Wings

    Science.gov (United States)

    Berdon, Randall; Wabick, Kevin; Buchholz, James; Johnson, Kyle; Thurow, Brian; University of Iowa Team; Auburn University Team

    2017-11-01

    A maneuvering rectangular wing of aspect ratio 2 is examined experimentally using dye visualization and PIV to characterize the initial development of the leading-edge vortex (LEV) during a rolling maneuver in a uniform free stream. Understanding the underlying physics during the early evolution of the vortex is important for developing strategies to manipulate vortex evolution. Varying the dimensionless radius of gyration of the wing (Rg/c, where Rg is the radius of gyration and c is the chord) and the advance ratio (J=U/ ΩRg, where U is the free-stream velocity and Ω is the roll rate) affects the structure of the vortex and its propensity to remain attached. The influence of these parameters will be discussed, toward identification of similarity parameters governing vortex development. This work is supported by the Air Force Office of Scientific Research (Grant Number FA9550-16-1-0107, Dr. Douglas Smith, program manager).

  13. Low cost heads-up virtual reality (HUVR) with optical tracking and haptic feedback

    KAUST Repository

    Margolis, Todd; DeFanti, Thomas A.; Dawe, Greg; Prudhomme, Andrew; Schulze, Jurgen P.; Cutchin, Steven

    2011-01-01

    consumer 3D HD flat screen TV with a half-silvered mirror to project any graphic image onto the user's hands and into the space surrounding them. With his or her head position optically tracked to generate the correct perspective view, the user maneuvers a

  14. Differential Evolution Optimization for Targeting Spacecraft Maneuver Plans

    Science.gov (United States)

    Mattern, Daniel

    2016-01-01

    Previous analysis identified specific orbital parameters as being safer for conjunction avoidance for the TDRS fleet. With TDRS-9 being considered an at-risk spacecraft, a potential conjunction concern was raised should TDRS-9 fail while at a longitude of 12W. This document summarizes the analysis performed to identify if these specific orbital parameters could be targeted using the remaining drift-termination maneuvers for the relocation of TDRS-9 from 41W longitude to 12W longitude.

  15. An expert system for pressurized water reactor load maneuvers

    International Nuclear Information System (INIS)

    Chaung Lin; Jungping Chen; Yihjiunn Lin; Lianshin Lin

    1993-01-01

    Restartup after reactor shutdown and load-follow operations are the important tasks in operating pressurized water reactors. Generally, the most efficient method is to apply constant axial offset control (CAOC) strategy during load maneuvers. An expert system using CAOC strategy, fuzzy reasoning, a two-node core model, and operational constraints has been developed. The computation time is so short that this system, which leads to an approximate closed-loop control, could be useful for on-site calculation

  16. Maintenance Maneuver Automation for an Adapted Cylindrical Shape TEC

    Directory of Open Access Journals (Sweden)

    Rafael Morales

    2016-09-01

    Full Text Available Several manufacturers have developed devices with which to harness tidal/current power in areas where the depth does not exceed 40 m. These are the so-called first generation Tidal Energy Converters (TEC, and they are usually fixed to the seabed by gravity. When carrying out maintenance tasks on these devices it is, therefore, necessary to remove the nacelles from their bases and raise them to the surface of the sea. They must subsequently be placed back on their bases. These tasks require special high performance ships, signifying high maintenance costs. The automation of emersion and immersion maneuvers will undoubtedly lead to lower costs, given that ships with less demanding requirements will be required for the aforementioned maintenance tasks. This research presents a simple two degrees of freedom dynamic model that can be used to control a first generation TEC that has been conceived of to harness energy from marine currents. The control of the system is carried out by means of a water ballast system located inside the nacelle of the main power unit and is used as an actuator to produce buoying vertical forces. A nonlinear control law based on a decoupling term for the closed loop depth and/or orientation control is also proposed in order to ensure adequate behavior when the TEC performs emersion and immersion maneuvers with only hydrostatic buoyancy forces. The control scheme is composed of an inner loop consisting of a linear and decoupled input/output relationship and the vector of friction and compressibility terms and an outer loop that operates with the tracking error vector in order to ensure the asymptotically exponential stability of the TEC posture. Finally, the effectiveness of the dynamic model and the controller approach is demonstrated by means of numerical simulations when the TEC is carrying out an emersion maneuver for the development of general maintenance tasks and an emersion maneuver for blade-cleaning maintenance

  17. Trajectory Control of Rendezvous with Maneuver Target Spacecraft

    Science.gov (United States)

    Zhou, Zhinqiang

    2012-01-01

    In this paper, a nonlinear trajectory control algorithm of rendezvous with maneuvering target spacecraft is presented. The disturbance forces on the chaser and target spacecraft and the thrust forces on the chaser spacecraft are considered in the analysis. The control algorithm developed in this paper uses the relative distance and relative velocity between the target and chaser spacecraft as the inputs. A general formula of reference relative trajectory of the chaser spacecraft to the target spacecraft is developed and applied to four different proximity maneuvers, which are in-track circling, cross-track circling, in-track spiral rendezvous and cross-track spiral rendezvous. The closed-loop differential equations of the proximity relative motion with the control algorithm are derived. It is proven in the paper that the tracking errors between the commanded relative trajectory and the actual relative trajectory are bounded within a constant region determined by the control gains. The prediction of the tracking errors is obtained. Design examples are provided to show the implementation of the control algorithm. The simulation results show that the actual relative trajectory tracks the commanded relative trajectory tightly. The predicted tracking errors match those calculated in the simulation results. The control algorithm developed in this paper can also be applied to interception of maneuver target spacecraft and relative trajectory control of spacecraft formation flying.

  18. State Estimation for Landing Maneuver on High Performance Aircraft

    Science.gov (United States)

    Suresh, P. S.; Sura, Niranjan K.; Shankar, K.

    2018-01-01

    State estimation methods are popular means for validating aerodynamic database on aircraft flight maneuver performance characteristics. In this work, the state estimation method during landing maneuver is explored for the first of its kind, using upper diagonal adaptive extended Kalman filter (UD-AEKF) with fuzzy based adaptive tunning of process noise matrix. The mathematical model for symmetrical landing maneuver consists of non-linear flight mechanics equation representing Aircraft longitudinal dynamics. The UD-AEKF algorithm is implemented in MATLAB environment and the states with bias is considered to be the initial conditions just prior to the flare. The measurement data is obtained from a non-linear 6 DOF pilot in loop simulation using FORTRAN. These simulated measurement data is additively mixed with process and measurement noises, which are used as an input for UD-AEKF. Then, the governing states that dictate the landing loads at the instant of touch down are compared. The method is verified using flight data wherein, the vertical acceleration at the aircraft center of gravity (CG) is compared. Two possible outcome of purely relying on the aircraft measured data is highlighted. It is observed that, with the implementation of adaptive fuzzy logic based extended Kalman filter tuned to adapt for aircraft landing dynamics, the methodology improves the data quality of the states that are sourced from noisy measurements.

  19. Development of power change maneuvering method for BWR

    International Nuclear Information System (INIS)

    Fukuzaki, Takaharu; Yamada, Naoyuki; Kiguchi, Takashi; Sakurai, Mikio.

    1985-01-01

    A power change maneuvering method for BWR has been proposed to generate an optimal power control maneuver, which realizes the power change operation closest to a power change demand pattern under operating constraints. The method searches for the maneuver as an optimization problem, where the variables are thermal power levels sampled from the demand pattern, the performance index is defined to express the power mismatch between demand and feasible patterns, and the constraints are limit lines on the thermal power-core flow rate map and limits on keeping fuel integrity. The usable feasible direction method is utilized as the optimization algorithm, with newly developed techniques for initial value generation and step length determination, which apply one-dimensional search and inverse-interpolation methods, respectively, to realize the effective search of the optimal solution. Simulation results show that a typical computing time is about 5 min by a general purpose computer and the method has been verified to be practical even for on-line use. (author)

  20. Capturing and analyzing wheelchair maneuvering patterns with mobile cloud computing.

    Science.gov (United States)

    Fu, Jicheng; Hao, Wei; White, Travis; Yan, Yuqing; Jones, Maria; Jan, Yih-Kuen

    2013-01-01

    Power wheelchairs have been widely used to provide independent mobility to people with disabilities. Despite great advancements in power wheelchair technology, research shows that wheelchair related accidents occur frequently. To ensure safe maneuverability, capturing wheelchair maneuvering patterns is fundamental to enable other research, such as safe robotic assistance for wheelchair users. In this study, we propose to record, store, and analyze wheelchair maneuvering data by means of mobile cloud computing. Specifically, the accelerometer and gyroscope sensors in smart phones are used to record wheelchair maneuvering data in real-time. Then, the recorded data are periodically transmitted to the cloud for storage and analysis. The analyzed results are then made available to various types of users, such as mobile phone users, traditional desktop users, etc. The combination of mobile computing and cloud computing leverages the advantages of both techniques and extends the smart phone's capabilities of computing and data storage via the Internet. We performed a case study to implement the mobile cloud computing framework using Android smart phones and Google App Engine, a popular cloud computing platform. Experimental results demonstrated the feasibility of the proposed mobile cloud computing framework.

  1. A Fuel-Efficient Conflict Resolution Maneuver for Separation Assurance

    Science.gov (United States)

    Bowe, Aisha Ruth; Santiago, Confesor

    2012-01-01

    Automated separation assurance algorithms are envisioned to play an integral role in accommodating the forecasted increase in demand of the National Airspace System. Developing a robust, reliable, air traffic management system involves safely increasing efficiency and throughput while considering the potential impact on users. This experiment seeks to evaluate the benefit of augmenting a conflict detection and resolution algorithm to consider a fuel efficient, Zero-Delay Direct-To maneuver, when resolving a given conflict based on either minimum fuel burn or minimum delay. A total of twelve conditions were tested in a fast-time simulation conducted in three airspace regions with mixed aircraft types and light weather. Results show that inclusion of this maneuver has no appreciable effect on the ability of the algorithm to safely detect and resolve conflicts. The results further suggest that enabling the Zero-Delay Direct-To maneuver significantly increases the cumulative fuel burn savings when choosing resolution based on minimum fuel burn while marginally increasing the average delay per resolution.

  2. Evaluation of Mathematical Models for Tankers’ Maneuvering Motions

    Directory of Open Access Journals (Sweden)

    Erhan AKSU

    2017-03-01

    Full Text Available In this study, the maneuvering performance of two tanker ships, KVLCC1 and KVLCC2 which have different stern forms are predicted using a system-based method. Two different 3 DOF (degrees of freedom mathematical models based on the MMG(Maneuvering Modeling Group concept areappliedwith the difference in representing lateral force and yawing moment by second and third order polynomials respectively. Hydrodynamic coefficients and related parameters used in the mathematical models of the same scale models of KVLCC1 and KVLCC2 ships are estimated by using experimental data of NMRI (National Maritime Research Institute. The simulations of turning circle with rudder angle ±35o , zigzag(±10o /±10o and zigzag (±20o /±20o maneuvers are carried out and compared with free running model test data of MARIN (Maritime Research Institute Netherlands in this study. As a result of the analysis, it can be summarised that MMG model based on the third order polynomial is superior to the one based on the second order polynomial in view of estimation accuracy of lateral hull force and yawing moment.

  3. "Spaghetti Maneuver": A useful tool in pediatric laparoscopy - Our experience

    Directory of Open Access Journals (Sweden)

    Antonio Marte

    2011-01-01

    Full Text Available Aims: The laparoscopic "Spaghetti Maneuver" consists in holding an organ by its extremity with a grasper and rolling it up around the tool to keep the organ stable and facilitate its traction within a small space. We describe our experience with the "Spaghetti Maneuver" in some minimally invasive procedures. Materials and Methods: We successfully adopted this technique in 13 patients (5F : 8M aged between 6 and 14 years (average age, 10 on whom we performed 7 appendectomies, 2 ureteral reimplantation and 4 cholecystectomies. In all cases, after the first steps, the appendix, the gallbladder and the ureter were rolled around the grasper and easily isolated; hemostasis was thus induced and the organ was mobilized until removal during cholecystectomy and appendectomy, and before the reimplantation in case of ureteral reimplantation. Results: We found that this technique facilitated significantly the acts of holding, isolating and removing, when necessary, the structures involved, which remained constantly within the visual field of the operator. This allowed a very ergonomic work setting, overcoming the problem of the "blind" zone, which represents a dangerous and invisible area out of the operator′s control during laparoscopy. Moreover the isolation maneuvers resulted easier and reduced operating time. Conclusion: We think that this technique is easy to perform and very useful, because it facilitates the dissection of these organs, by harmonizing and stabilizing the force of traction exercised.

  4. Universal spin-momentum locked optical forces

    Energy Technology Data Exchange (ETDEWEB)

    Kalhor, Farid [Department of Electrical and Computer Engineering, University of Alberta, Edmonton, Alberta T6G 1H9 (Canada); Thundat, Thomas [Department of Chemical and Materials Engineering, University of Alberta, Edmonton, Alberta T6G 1H9 (Canada); Jacob, Zubin, E-mail: zjacob@purdue.edu [Department of Electrical and Computer Engineering, University of Alberta, Edmonton, Alberta T6G 1H9 (Canada); Birck Nanotechnology Center, Department of Electrical and Computer Engineering, Purdue University, West Lafayette, Indiana 47906 (United States)

    2016-02-08

    Evanescent electromagnetic waves possess spin-momentum locking, where the direction of propagation (momentum) is locked to the inherent polarization of the wave (transverse spin). We study the optical forces arising from this universal phenomenon and show that the fundamental origin of recently reported non-trivial optical chiral forces is spin-momentum locking. For evanescent waves, we show that the direction of energy flow, the direction of decay, and the direction of spin follow a right hand rule for three different cases of total internal reflection, surface plasmon polaritons, and HE{sub 11} mode of an optical fiber. Furthermore, we explain how the recently reported phenomena of lateral optical force on chiral and achiral particles are caused by the transverse spin of the evanescent field and the spin-momentum locking phenomenon. Finally, we propose an experiment to identify the unique lateral forces arising from the transverse spin in the optical fiber and point to fundamental differences of the spin density from the well-known orbital angular momentum of light. Our work presents a unified view on spin-momentum locking and how it affects optical forces on chiral and achiral particles.

  5. A novel mode-locking technique

    International Nuclear Information System (INIS)

    Chen Shaoh; Chen Youming; Chen Taolue; Si Xiangdong; Yang Yi; Deng Ximing

    1993-01-01

    A novel mode-locked Nd:YAG oscillator has been developed by using an ultrafast photoconductive feedback controlled loop, and mode-locked pulses with a duration of 100ps have been obtained. The energy instability of the pulse trains is ±5%. In this type of mode-locking technology, a type of deep-level doped GaAs (Cr-doped) photoconductive switch, which has a fast response in time and is free of avalance process, is used to drive a Pockels' cell to realize mode-locking. The dark resistance of this type of photoconductive switch is 6 orders of magnitude higher than that of the intrinsic single-crystal silicon, and it can reach a level as high as 10 9 ohms. Consequently, it is able to withstand longterm operation at several thousand DC volts. By means of the photoconductive ohmic switch characteristics, the authors have designed a positive feedback control network which has a very fast response time, and can couple a voltage of up to a thousand volts. Using this unit in a Nd:YAG laser, they have successfully realized a very stable mode-locked pulse train with pulse width shorter than 100 ps. The operation principle, and the results of the preliminary experiments are presented here. 1 ref., 3 figs

  6. Hersendood. Mackies leibniziaanse herinterpretatie van Lockes theorie van persoonsidentiteit

    OpenAIRE

    De Vleeschouwer, Gregory

    2009-01-01

    In his book, 'Problems from Locke', John Leslie Mackie presents a theory of personal identity (pi) that is meant to be a supplement and correction of Locke's pi-theory. In a first part I introduce the criterion of pi that was standard before Locke's pi-theory. By showing in a second part how Locke reacted against this traditional criterion, I show wherein the singularity of Locke's pi-theory exists. In a third part I explain how Leibniz is moved by the same solicitude as Locke, but also how h...

  7. Discretely tunable micromachined injection-locked lasers

    International Nuclear Information System (INIS)

    Cai, H; Yu, M B; Lo, G Q; Kwong, D L; Zhang, X M; Liu, A Q; Liu, B

    2010-01-01

    This paper reports a micromachined injection-locked laser (ILL) to provide tunable discrete wavelengths. It utilizes a non-continuously tunable laser as the master to lock a Fabry–Pérot semiconductor laser chip. Both lasers are integrated into a deep-etched silicon chip with dimensions of 3 mm × 3 mm × 0.8 mm. Based on the experimental results, significant improvements in the optical power and spectral purity have been achieved in the fully locked state, and optical hysteresis and bistability have also been observed in response to the changes of the output wavelength and optical power of the master laser. As a whole system, the micromachined ILL is able to provide single mode, discrete wavelength tuning, high power and direct modulation with small size and single-chip solution, making it promising for advanced optical communications such as wavelength division multiplexing optical access networks.

  8. Weak-light phase locking for LISA

    International Nuclear Information System (INIS)

    McNamara, Paul W

    2005-01-01

    The long armlengths of the LISA interferometer, and the finite aperture of the telescope, lead to an optical power attenuation of ∼10 -10 of the transmitted to received light. Simple reflection at the end of the arm is therefore not an optimum interferometric design. Instead, a local laser is offset phase locked to the weak incoming beam, transferring the phase information of the incoming to the outgoing light. This paper reports on an experiment to characterize a weak-light phase-locking scheme suitable for LISA in which a diode-pumped, Nd:YAG, non-planar ring oscillator (NPRO) is offset phase locked to a low-power (13 pW) frequency stabilized master NPRO. Preliminary results of the relative phase noise of the slave laser shows shot noise limited performance above 0.4 Hz. Excess noise is observed at lower frequencies, most probably due to thermal effects in the optical arrangement and phase-sensing electronics

  9. Using river locks to teach hydrodynamic concepts

    Science.gov (United States)

    Carvalho-Santos, Vagson L.; Mendes, Thales C.; Silva, Enisvaldo C.; Rios, Márcio L.; Silva, Anderson A. P.

    2013-11-01

    In this work, the use of a river lock as a non-formal setting for teaching hydrodynamical concepts is proposed. In particular, we describe the operation of a river lock situated at the Sobradinho dam, on the São Francisco River (Brazil). A model to represent and to analyse the dynamics of river lock operation is presented and we derive the dynamical equations for the rising of the water column as an example to understand the Euler equation. Furthermore, with this activity, we enable the integration of content initially introduced in the classroom with practical applications, thereby allowing the association of physical themes to content relevant in disciplines such as history and geography. In addition, experiences of this kind enable teachers to talk about the environmental and social impacts caused by the construction of a dam and, consequently, a crossover of concepts has been made possible, leading to more meaningful learning for the students.

  10. Using river locks to teach hydrodynamic concepts

    International Nuclear Information System (INIS)

    Carvalho-Santos, Vagson L; Mendes, Thales C; Silva, Enisvaldo C; Rios, Márcio L; Silva, Anderson A P

    2013-01-01

    In this work, the use of a river lock as a non-formal setting for teaching hydrodynamical concepts is proposed. In particular, we describe the operation of a river lock situated at the Sobradinho dam, on the São Francisco River (Brazil). A model to represent and to analyse the dynamics of river lock operation is presented and we derive the dynamical equations for the rising of the water column as an example to understand the Euler equation. Furthermore, with this activity, we enable the integration of content initially introduced in the classroom with practical applications, thereby allowing the association of physical themes to content relevant in disciplines such as history and geography. In addition, experiences of this kind enable teachers to talk about the environmental and social impacts caused by the construction of a dam and, consequently, a crossover of concepts has been made possible, leading to more meaningful learning for the students. (paper)

  11. John Locke and the right to resistance

    Directory of Open Access Journals (Sweden)

    Jovanov Ilija D.

    2015-01-01

    Full Text Available John Locke was a great thinker and many works have been devoted to clear up his theories. One of the most significant, stated in his principal work, Two Treatises of Government, is the theory of the right to resistance. It was a bit revolutionary then, and to a large extent it is today. Domination of legal positivism is negation of that, by Locke, natural right. However, the fact is that in recent times the resistance to the established power occurs in a number of countries and in different forms, so that the idea of the right to resistance becomes live question again. In this regard it is interesting to consider Locke's viewpoint on this important issue and to determine whether his theory on the resistance is applicable in modern societies.

  12. SWITCHED REFERENCE PHASE LOCK LOOP (SRPLL)

    International Nuclear Information System (INIS)

    KERNER, T.

    2001-01-01

    The Brookhaven National Laboratory Relativistic Heavy Ion Collider (RHIC) has two beam synchronous event links (BSL), one for each ring, which use the 28 MHz ring low level rf to distribute event codes synchronously with a precise phase relationship to the beam. During a cogging reset just before injection, the low level rf sine wave is interrupted which causes the BSL receivers to lose lock. Lock loss in turn causes false triggers and other undesirable-effects on the beam position monitors (BPM), ionization profile monitors (IPM), the tune meter and various experiments which use the BSLs. To rectify these problems, a SRPLL has been inserted between the beam synchronous master and the low level rf source. The SRPLL inserts a frequency and phase continuous splice over the dead-band gap in the rf source created during a cogging reset. The splice removes the gap and prevents the distributed BSL receivers from losing lock

  13. The evaluation of effectiveness of 3DCA using vacuum bag(Vac-Lock) for patient immobilization device

    International Nuclear Information System (INIS)

    Lee, Young Chul; Lee, Chul Bin; Kang, No Hyun; Kim, Dong Euk; Lee, Jung Yong; Jeong, In Pyo

    2004-01-01

    Patient immobilization is crucial factor for radiation therapy. Generally, we have been used vacuum bag immobilization device(Vac-Lock) for whole body immobilization. In order to easily set up of vacuum bag(Vac-Lock), we made a 3DCA(3-Dimensional Conformal Accessory). The purpose of this study is evaluation of effectiveness of 3DCA using Vack-Lock for patient immobilization. We made 3DCA(3-Dimensional Conformal Accessory) tool of wooden boards. The reasons to choice of wooden boards are its easily handling nature and cheap expenses. (1) We reduced man power from 5-6 persons to 1 person to make immobilizations, (2) Shortened work time from 1 hour to within 10 minutes. (3) Avoid a collision to treatment gantry head. (4) Its shapes are smart and clean. We have made and used 3DCA(3-Dimensional Conformal Accessory) tool was very effective and convenience for the patients and users.

  14. High-Order Frequency-Locked Loops

    DEFF Research Database (Denmark)

    Golestan, Saeed; Guerrero, Josep M.; Quintero, Juan Carlos Vasquez

    2017-01-01

    In very recent years, some attempts for designing high-order frequency-locked loops (FLLs) have been made. Nevertheless, the advantages and disadvantages of these structures, particularly in comparison with a standard FLL and high-order phase-locked loops (PLLs), are rather unclear. This lack...... study, and its small-signal modeling, stability analysis, and parameter tuning are presented. Finally, to gain insight about advantages and disadvantages of high-order FLLs, a theoretical and experimental performance comparison between the designed second-order FLL and a standard FLL (first-order FLL...

  15. Mode-locked silicon evanescent lasers.

    Science.gov (United States)

    Koch, Brian R; Fang, Alexander W; Cohen, Oded; Bowers, John E

    2007-09-03

    We demonstrate electrically pumped lasers on silicon that produce pulses at repetition rates up to 40 GHz. The mode locked lasers generate 4 ps pulses with low jitter and extinction ratios above 18 dB, making them suitable for data and telecommunication transmitters and for clock generation and distribution. Results of both passive and hybrid mode locking are discussed. This type of device could enable new silicon based integrated technologies, such as optical time division multiplexing (OTDM), wavelength division multiplexing (WDM), and optical code division multiple access (OCDMA).

  16. Drag and Torque on Locked Screw Propeller

    Directory of Open Access Journals (Sweden)

    Tomasz Tabaczek

    2014-09-01

    Full Text Available Few data on drag and torque on locked propeller towed in water are available in literature. Those data refer to propellers of specific geometry (number of blades, blade area, pitch and skew of blades. The estimation of drag and torque of an arbitrary propeller considered in analysis of ship resistance or propulsion is laborious. The authors collected and reviewed test data available in the literature. Based on collected data there were developed the empirical formulae for estimation of hydrodynamic drag and torque acting on locked screw propeller. Supplementary CFD computations were carried out in order to prove the applicability of the formulae to modern moderately skewed screw propellers.

  17. John Locke on persons and personal identity

    OpenAIRE

    Boeker, Ruth

    2013-01-01

    John Locke claims both that ‘person’ is a forensic term and that personal identity consists in sameness of consciousness. The aim of my dissertation is to explain and critically assess how Locke links his moral and legal account of personhood to his account of personal identity in terms of sameness of consciousness. My interpretation of Locke’s account of persons and personal identity is embedded in Locke’s sortal-dependent account of identity. Locke’s sortal-dependent ac...

  18. Optimal database locks for efficient integrity checking

    DEFF Research Database (Denmark)

    Martinenghi, Davide

    2004-01-01

    In concurrent database systems, correctness of update transactions refers to the equivalent effects of the execution schedule and some serial schedule over the same set of transactions. Integrity constraints add further semantic requirements to the correctness of the database states reached upon...... the execution of update transactions. Several methods for efficient integrity checking and enforcing exist. We show in this paper how to apply one such method to automatically extend update transactions with locks and simplified consistency tests on the locked entities. All schedules produced in this way...

  19. Biomechanical Comparison of 3 Inferiorly Directed Versus 3 Superiorly Directed Locking Screws on Stability in a 3-Part Proximal Humerus Fracture Model.

    Science.gov (United States)

    Donohue, David M; Santoni, Brandon G; Stoops, T Kyle; Tanner, Gregory; Diaz, Miguel A; Mighell, Mark

    2018-06-01

    To quantify the stability of 3 points of inferiorly directed versus 3 points of superiorly directed locking screw fixation compared with the full contingent of 6 points of locked screw fixation in the treatment of a 3-part proximal humerus fracture. A standardized 3-part fracture was created in 10 matched pairs (experimental groups) and 10 nonmatched humeri (control group). Osteosynthesis was performed using 3 locking screws in the superior hemisphere of the humeral head (suspension), 3 locking screws in the inferior hemisphere (buttress), or the full complement of 6 locking screws (control). Specimens were tested in varus cantilever bending (7.5 Nm) to 10,000 cycles or failure. Construct survival (%) and the cycles to failure were compared. Seven of 10 controls survived the 10,000-cycle runout (70%: 8193 average cycles to failure). No experimental constructs survived the 10,000-cycle runout. Suspension and buttress screw groups failed an average of 331 and 516 cycles, respectively (P = 1.00). The average number of cycles to failure and the number of humeri surviving the 10,000-cycle runout were greater in the control group than in the experimental groups (P ≤ 0.006). Data support the use of a full contingent of 6 points of locking screw fixation over 3 superior or 3 inferior points of fixation in the treatment of a 3-part proximal humerus fracture with a locking construct. No biomechanical advantage to the 3 buttress or 3 suspension screws used in isolation was observed.

  20. Navigation Study, Colorado Locks, Colorado River, Matagorda, Texas

    National Research Council Canada - National Science Library

    McCollum, Randy

    2000-01-01

    A 1:70 physical navigation model was built to replicate the Matagorda Locks, approximately one mile of the GIWW east of the locks, approximately one-half mile of the Colorado River north of the GIWW...

  1. Flued head replacement alternatives

    International Nuclear Information System (INIS)

    Smetters, J.L.

    1987-01-01

    This paper discusses flued head replacement options. Section 2 discusses complete flued head replacement with a design that eliminates the inaccessible welds. Section 3 discusses alternate flued head support designs that can drastically reduce flued head installation costs. Section 4 describes partial flued head replacement designs. Finally, Section 5 discusses flued head analysis methods. (orig./GL)

  2. Goniometer head

    International Nuclear Information System (INIS)

    Dzhazairov-Kakhramanov, V.; Berger, V.D.; Kadyrzhanov, K.K.; Zarifov, R.A.

    1994-01-01

    The goniometer head is an electromechanical instrument that performs the independent transfer of a testing sample on three coordinate axes (X, Y, Z) within limits of ±8 mm and independent rotation relative of these directions. The instrument comprises a sample holder, bellows component and three electrometer drives. The sample holder rotates around the axes X and Y, and is installed on the central arm which rotates around axis Z. One characteristic of this instrument is its independence which allows its use in any camera for researches in the field of radiation physics. 2 figs

  3. Using the Two-Burn Escape Maneuver for Fast Transfers in the Solar System and Beyond

    Science.gov (United States)

    Adams, Robert B.; Richardson, Georgia A.

    2010-01-01

    The two-burn maneuver to escape the gravitational pull of a central body is described. The maneuver, originally suggested by Hermann Oberth, improves efficiency considerably for a wide range of missions of interest in space exploration and scientific investigation. A clear delineation of when the maneuver is more effective is given, as are methods to extract the most advantage when using the maneuver. Some examples are given of how this maneuver can enable exploration of the outer solar system, near interstellar space, and crewed missions to Mars and beyond. The maneuver has the potential to halve the required infrastructure associated with a crewed mission to Mars and achieve increased solar escape velocities with existing spacecraft technologies.

  4. Locks at reactor safety containments of nuclear power plants

    International Nuclear Information System (INIS)

    1978-12-01

    The rule is to be applied for material access locks. A material access lock as defined by this rule is a pressure resistant and technically gas-tight hollow body that is connected with the containment and has got two doors, the inner door of which connects the lock chamber with the interior of the containment and the outer door connects the lock chamber with the outside. It serves exclusively for transferring material or objects. (orig./HP) [de

  5. Performance Monitoring System: Summary of Lock Statistics. Revision 1.

    Science.gov (United States)

    1985-12-01

    2751 84 4057 4141 526 798 18 1342 5727 19 5523 3996 4587 8583 1056 1630 35 2721 6536LOCK A DAMI 2 AUXILIARY I Ins NO DATA RECORDD FOR THIS LOCK- " LOCK I...TOTAL (KTOMS) ’ - (AVt OPNP ETC) ’’ ,q [ " ARKANSAS RIVER "" FORRELL LOCK IP 7A/3TRC 9/N83 UPBOUID STATISTICS ISO 53 42 M6 553 356 909 221 41 21 M8

  6. Multiprocessor Real-Time Locking Protocols for Replicated Resources

    Science.gov (United States)

    2016-07-01

    assignment problem, the ac- tual identities of the allocated replicas must be known. When locking protocols are used, tasks may experience delays due to both...Multiprocessor Real-Time Locking Protocols for Replicated Resources ∗ Catherine E. Jarrett1, Kecheng Yang1, Ming Yang1, Pontus Ekberg2, and James H...replicas to execute. In prior work on replicated resources, k-exclusion locks have been used, but this restricts tasks to lock only one replica at a time. To

  7. Computing and Visualizing Reachable Volumes for Maneuvering Satellites

    International Nuclear Information System (INIS)

    Jiang, M.; de Vries, W.H.; Pertica, A.J.; Olivier, S.S.

    2011-01-01

    Detecting and predicting maneuvering satellites is an important problem for Space Situational Awareness. The spatial envelope of all possible locations within reach of such a maneuvering satellite is known as the Reachable Volume (RV). As soon as custody of a satellite is lost, calculating the RV and its subsequent time evolution is a critical component in the rapid recovery of the satellite. In this paper, we present a Monte Carlo approach to computing the RV for a given object. Essentially, our approach samples all possible trajectories by randomizing thrust-vectors, thrust magnitudes and time of burn. At any given instance, the distribution of the 'point-cloud' of the virtual particles defines the RV. For short orbital time-scales, the temporal evolution of the point-cloud can result in complex, multi-reentrant manifolds. Visualization plays an important role in gaining insight and understanding into this complex and evolving manifold. In the second part of this paper, we focus on how to effectively visualize the large number of virtual trajectories and the computed RV. We present a real-time out-of-core rendering technique for visualizing the large number of virtual trajectories. We also examine different techniques for visualizing the computed volume of probability density distribution, including volume slicing, convex hull and isosurfacing. We compare and contrast these techniques in terms of computational cost and visualization effectiveness, and describe the main implementation issues encountered during our development process. Finally, we will present some of the results from our end-to-end system for computing and visualizing RVs using examples of maneuvering satellites.

  8. Simulation of upwind maneuvering of a sailing yacht

    Science.gov (United States)

    Harris, Daniel Hartrick

    A time domain maneuvering simulation of an IACC class yacht suitable for the analysis of unsteady upwind sailing including tacking is presented. The simulation considers motions in six degrees of freedom. The hydrodynamic and aerodynamic loads are calculated primarily with unsteady potential theory supplemented by empirical viscous models. The hydrodynamic model includes the effects of incident waves. Control of the rudder is provided by a simple rate feedback autopilot which is augmented with open loop additions to mimic human steering. The hydrodynamic models are based on the superposition of force components. These components fall into two groups, those which the yacht will experience in calm water, and those due to incident waves. The calm water loads are further divided into zero Froude number, or "double body" maneuvering loads, hydrostatic loads, gravitational loads, free surface radiation loads, and viscous/residual loads. The maneuvering loads are calculated with an unsteady panel code which treats the instantaneous geometry of the yacht below the undisturbed free surface. The free surface radiation loads are calculated via convolution of impulse response functions derived from seakeeping strip theory. The viscous/residual loads are based upon empirical estimates. The aerodynamic model consists primarily of a database of steady state sail coefficients. These coefficients treat the individual contributions to the total sail force of a number of chordwise strips on both the main and jib. Dynamic effects are modeled by using the instantaneous incident wind velocity and direction as the independent variables for the sail load contribution of each strip. The sail coefficient database was calculated numerically with potential methods and simple empirical viscous corrections. Additional aerodynamic load calculations are made to determine the parasitic contributions of the rig and hull. Validation studies compare the steady sailing hydro and aerodynamic loads

  9. Computing and Visualizing Reachable Volumes for Maneuvering Satellites

    Science.gov (United States)

    Jiang, M.; de Vries, W.; Pertica, A.; Olivier, S.

    2011-09-01

    Detecting and predicting maneuvering satellites is an important problem for Space Situational Awareness. The spatial envelope of all possible locations within reach of such a maneuvering satellite is known as the Reachable Volume (RV). As soon as custody of a satellite is lost, calculating the RV and its subsequent time evolution is a critical component in the rapid recovery of the satellite. In this paper, we present a Monte Carlo approach to computing the RV for a given object. Essentially, our approach samples all possible trajectories by randomizing thrust-vectors, thrust magnitudes and time of burn. At any given instance, the distribution of the "point-cloud" of the virtual particles defines the RV. For short orbital time-scales, the temporal evolution of the point-cloud can result in complex, multi-reentrant manifolds. Visualization plays an important role in gaining insight and understanding into this complex and evolving manifold. In the second part of this paper, we focus on how to effectively visualize the large number of virtual trajectories and the computed RV. We present a real-time out-of-core rendering technique for visualizing the large number of virtual trajectories. We also examine different techniques for visualizing the computed volume of probability density distribution, including volume slicing, convex hull and isosurfacing. We compare and contrast these techniques in terms of computational cost and visualization effectiveness, and describe the main implementation issues encountered during our development process. Finally, we will present some of the results from our end-to-end system for computing and visualizing RVs using examples of maneuvering satellites.

  10. Lock-free parallel garbage collection

    NARCIS (Netherlands)

    H. Gao; J.F. Groote (Jan Friso); W.H. Hesselink (Wim)

    2005-01-01

    htmlabstract This paper presents a lock-free parallel algorithm for mark&sweep garbage collection (GC) in a realistic model using synchronization primitives compare-and-swap (CAS) and load-linked/store-conditional (LL/SC) offered by machine architectures. Mutators and collectors can simultaneously

  11. A Mode Locked UV-FEL

    CERN Document Server

    Parvin, Parviz

    2004-01-01

    An appropriate resonator has been designed to generate femtosecond mode locked pulses in a UV FEL with the modulator performance based on the gain switching. The gain broadening due to electron energy spread affects on the gain parameters, small signal gain (γ0) and saturation intensity (Is), to determine the optimum output coupling as small.

  12. CMOS switched current phase-locked loop

    NARCIS (Netherlands)

    Leenaerts, D.M.W.; Persoon, G.G.; Putter, B.M.

    1997-01-01

    The authors present an integrated circuit realisation of a switched current phase-locked loop (PLL) in standard 2.4 µm CMOS technology. The centre frequency is tunable to 1 MHz at a clock frequency of 5.46 MHz. The PLL has a measured maximum phase error of 21 degrees. The chip consumes

  13. Phase locking of optically coupled lasers

    International Nuclear Information System (INIS)

    Glova, A F

    2003-01-01

    A review of studies of the properties of radiation from optically coupled lasers is presented. The methods for phase locking the fields in optically coupled lasers of different types are considered and the methods for supermode selection and correction of the radiation pattern are discussed. (review)

  14. A locked nucleic Acid-based nanocrawler

    DEFF Research Database (Denmark)

    Astakhova, I Kira; Pasternak, Karol; Campbell, Meghan A

    2013-01-01

    Herein we introduce a novel fluorescent LNA/DNA machine, a nanocrawler, which reversibly moves along a directionally polar complementary road controlled by affinity-enhancing locked nucleic acid (LNA) monomers and additional regulatory strands. Polyaromatic hydrocarbon (PAH) dyes attached to 2...

  15. 49 CFR 236.742 - Dog, locking.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Dog, locking. 236.742 Section 236.742 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION..., MAINTENANCE, AND REPAIR OF SIGNAL AND TRAIN CONTROL SYSTEMS, DEVICES, AND APPLIANCES Definitions § 236.742 Dog...

  16. A New Perspective on Job Lock

    Science.gov (United States)

    Huysse-Gaytandjieva, Anna; Groot, Wim; Pavlova, Milena

    2013-01-01

    This paper analyses the situation when employees fail to adapt to overall job dissatisfaction. By combining the existing knowledge in economics on job lock and in psychology on employees' feeling of being "stuck" at work, the paper explains why some employees fail to adapt when dissatisfied with their job. Thus, the paper aims to expand…

  17. Locks & keys service moves to building 55

    CERN Multimedia

    2012-01-01

    Please note that as of July 12 Locks & keys service will be at building 55 second floor. The opening hours are as follows: 08:30 am to 12:30 pm - 1:30 pm to 5:30 pm. The procedures and rules relating to applications for key and cylinder have not changed. GI-IS Group

  18. A photovoltaic module diagnostic setup for lock-in-thermography and lock-in electroluminescence imaging

    DEFF Research Database (Denmark)

    Parikh, Harsh; Spataru, Sergiu; Sera, Dezso

    2018-01-01

    Electroluminescence (EL) imaging and infrared (IRT) thermography techniques have become indispensable tools in recent years for health diagnostic of PV modules in solar industry application. Complementary to these imaging methods, lock-in techniques can effectively remove noise by periodically...... modulating the input signal and averaging it over a desired number of periods. We propose a combined lock-in EL and lock-in IRT diagnostic setup for accurate analysis of different types of faults occurring in a solar module. The setup is built around a Goldeye CL-033 high-speed SWIR camera, which can acquire...... experimental work on a (36/72) cell solar module using combined (EL) or (IRT) lock-in-thermography. The setup allows one to investigate the different technological problems that can occur when performing PV diagnostics in drone-based inspections....

  19. Navigation Study of Lower Lock Approach, John Day Lock and Dam, Columbia River, Oregon

    National Research Council Canada - National Science Library

    Wilson, Donald

    2001-01-01

    Representatives of the Columbia River Towing Association reported recent structural and/or operational changes at John Day Lock and Dam have created difficult navigation conditions for tows entering...

  20. 30 CFR 56.12068 - Locking transformer enclosures.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Locking transformer enclosures. 56.12068 Section 56.12068 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND... § 56.12068 Locking transformer enclosures. Transformer enclosures shall be kept locked against...

  1. Maneuvering a pilot implementation to align agendas across sectors

    DEFF Research Database (Denmark)

    Mønsted, Troels; Hertzum, Morten; Søndergaard, Jens

    2017-01-01

    A prerequisite for pilot implementations in complex organizational settings is that the agendas of the stakeholders of the system are maneuvered into alignment. In this paper we present a study of the pilot implementation of the IT-supported, preventive intervention TOF (Tidlig Opsporing og...... Forebyggelse). A core element of TOF is an IT system that stratifies citizens into risk groups on the basis of self-reported lifestyle information and data retrieved from the medical records of the general practitioners (GPs). In addition, the system facilitates cross-sectoral coordination between preventive...

  2. Near Earth Asteroid redirect missions based on gravity assist maneuver

    Science.gov (United States)

    Ledkov, Anton; Shustov, Boris M.; Eismont, Natan; Boyarsky, Michael; Nazirov, Ravil; Fedyaev, Konstantin

    During last years several events attracted world community attention to the hazards of hitting the Earth by sky objects. One of these objects is Apophis asteroid what was expected with nonzero probability to hit the Earth in 2036. Luckily after more precise measurements this event is considered as practically improbable. But the other object has really reached the Earth, entered the atmosphere in the Chelyabinsk area and caused vast damages. After this the hazardous near Earth objects problem received practical confirmation of the necessity to find the methods of its resolution. The methods to prevent collision of the dangerous sky object with the Earth proposed up to now look not practical enough if one mentions such as gravitational tractor or changing the reflectivity of the asteroid surface. Even the method supposing the targeting of the spacecraft to the hazardous object in order to deflect it from initial trajectory by impact does not work because its low mass as compared with the mass of asteroid to be deflected. For example the mass of the Apophis is estimated to be about 40 million tons but the spacecraft which can be launched to intercept the asteroid using contemporary launchers has the mass not more than 5 tons. So the question arises where to find the heavier projectile which is possible to direct to the dangerous object? The answer proposed in our paper is very simple: to search it among small near Earth asteroids. As small ones we suppose those which have the cross section size not more than 12-15 meters and mass not exceeding 1500 -1700 tons. According to contemporary estimates the number of such asteroids is not less than 100000. The other question is how to redirect such asteroid to the dangerous one. In the paper the possibilities are studied to use for that purpose gravity assist maneuvers near Earth. It is shown that even among asteroids included in contemporary catalogue there are the ones which could be directed to the trajectory of the

  3. Improving aggregate behavior in parking lots with appropriate local maneuvers

    KAUST Repository

    Rodriguez, Samuel

    2013-11-01

    In this paper we study the ingress and egress of pedestrians and vehicles in a parking lot. We show how local maneuvers executed by agents permit them to create trajectories in constrained environments, and to resolve the deadlocks between them in mixed-flow scenarios. We utilize a roadmap-based approach which allows us to map complex environments and generate heuristic local paths that are feasible for both pedestrians and vehicles. Finally, we examine the effect that some agent-behavioral parameters have on parking lot ingress and egress. © 2013 IEEE.

  4. Space Shuttle OMS engine valve technology. [Orbital Maneuvering System

    Science.gov (United States)

    Wichmann, H.

    1974-01-01

    Valve technology program to determine shutoff valve concepts suitable for the Orbital Maneuvering System (OMS) engine of the Space Shuttle. The tradeoff studies selected the electric torque motor operated dual poppet and ball valves as the most desirable valve concepts for the OMS Engine Shutoff Valve. A prototype of one of these concepts was built and subjected to a design verification program. A number of unique features were designed to include the required contamination insensitivity, operating fluid compatibility, decontamination capability, minimum maintenance requirement and long service life capability.

  5. Limited War in the Precision Engagement Era: The Balance Between Dominant Maneuver and Precision Engagement

    National Research Council Canada - National Science Library

    Hedstrom, Marvin

    2001-01-01

    .... German historian Hans Delbruck's two strategies of warfare: annihilation and exhaustion, and American military theorist Robert Leonhard's concepts of attrition and maneuver are examined to establish the relationship...

  6. Study on zigzag maneuver characteristics of V-U very large crude oil (VLCC) tankers

    Science.gov (United States)

    Jaswar, Maimun, A.; Wahid, M. A.; Priyanto, A.; Zamani, Pauzi, Saman

    2012-06-01

    The Department of Marine Technology at the Faculty of Mechanical Engineering, University Teknologi Malaysia has recently developed an Ship Maneuverability tool which intends to upgrade student's level understanding the application of fluid dynamic on interaction between hull, propeller, and rudder during maneuvering. This paper discusses zigzag maneuver for conventional Very Large Crude Oil (VLCC) ships with the same principal dimensions but different stern flame shape. 10/10 zigzag maneuver characteristics of U and V types of VLCC ships are investigated. Simulation results for U-type show a good agreement with the experimental data, but V-type not good agreement with experimental one. Further study on zigzag maneuver characteristics are required.

  7. Locked modes and magnetic field errors in MST

    International Nuclear Information System (INIS)

    Almagri, A.F.; Assadi, S.; Prager, S.C.; Sarff, J.S.; Kerst, D.W.

    1992-06-01

    In the MST reversed field pinch magnetic oscillations become stationary (locked) in the lab frame as a result of a process involving interactions between the modes, sawteeth, and field errors. Several helical modes become phase locked to each other to form a rotating localized disturbance, the disturbance locks to an impulsive field error generated at a sawtooth crash, the error fields grow monotonically after locking (perhaps due to an unstable interaction between the modes and field error), and over the tens of milliseconds of growth confinement degrades and the discharge eventually terminates. Field error control has been partially successful in eliminating locking

  8. Propulsive Maneuver Design for the 2007 Mars Phoenix Lander Mission

    Science.gov (United States)

    Raofi, Behzad; Bhat, Ramachandra S.; Helfrich, Cliff

    2008-01-01

    On May 25, 2008, the Mars Phoenix Lander (PHX) successfully landed in the northern planes of Mars in order to continue and complement NASA's "follow the water" theme as its predecessor Mars missions, such as Mars Odyssey (ODY) and Mars Exploration Rovers, have done in recent years. Instruments on the lander, through a robotic arm able to deliver soil samples to the deck, will perform in-situ and remote-sensing investigations to characterize the chemistry of materials at the local surface, subsurface, and atmosphere. Lander instruments will also identify the potential history of key indicator elements of significance to the biological potential of Mars, including potential organics within any accessible water ice. Precise trajectory control and targeting were necessary in order to achieve the accurate atmospheric entry conditions required for arriving at the desired landing site. The challenge for the trajectory control maneuver design was to meet or exceed these requirements in the presence of spacecraft limitations as well as other mission constraints. This paper describes the strategies used, including the specialized targeting specifically developed for PHX, in order to design and successfully execute the propulsive maneuvers that delivered the spacecraft to its targeted landing site while satisfying the planetary protection requirements in the presence of flight system constraints.

  9. Wall locking and multiple nonlinear states of magnetic islands

    International Nuclear Information System (INIS)

    Persson, Mikael; Australian National Univ., Canberra, ACT

    1994-01-01

    The nonlinear evolution of magnetic islands is analysed in configurations with multiple resonant magnetic surfaces. The existence of multiple nonlinear steady states, is discussed. These are shown to be associated with states where the dynamics around the different rational surfaces are coupled or decoupled and in the presence of a wall of finite resistivity may correspond wall-locked or non-wall-locked magnetic islands. For the case of strong wall stabilization the locking is shown to consist of two different phases. During the first phase the locking of the plasma at the different rational surfaces occurs. Only when the outermost resonant magnetic surface has locked to the inner surfaces can the actual wall locking process take place. Consequently, wall locking, of a global mode, involving more than one rational surface, can be prevented by the decoupling of the resonant magnetic surfaces by plasma rotation. Possible implications on tokamak experiments are discussed. (author)

  10. Power spectrum of an injection-locked Josephson oscillator

    International Nuclear Information System (INIS)

    Stancampiano, C.V.; Shapiro, S.

    1975-01-01

    Experiments have shown that a Josephson oscillator, exposed to a weak narrow-band input signal, exhibits behavior characteristic of an injection-locked oscillator. When in lock, Adler's theory of injection locking describes the experimental observations reasonably well. The range of applicability of the theory is extended to the out-of-lock regime where a spectrum of output frequencies is observed. Obtaining the theoretical output power spectrum requires solving a differential equation having the same form as the equation describing the resistively shunted junction model of Stewart and of McCumber. Experimental measurements of the output spectrum of a nearly locked Josephson oscillator are shown to be in reasonable agreement with the theory. Additional results discussed briefly include the observation of a frequency dependence of the locked Josephson oscillator output and experiments in which a Josephson oscillator-mixer was injection locked by a weak signal at the rf

  11. Is HEADS in our heads?

    DEFF Research Database (Denmark)

    Boisen, Kirsten A; Hertz, Pernille Grarup; Blix, Charlotte

    2016-01-01

    contraception], Safety, Self-harm) interview is a feasible way of exploring health risk behaviors and resilience. OBJECTIVE: The purpose of this study was to evaluate how often HEADS topics were addressed according to young patients and staff in pediatric and adult outpatient clinics. METHODS: We conducted...... care professionals participated. We found only small reported differences between staff and young patients regarding whether home, education, and activity were addressed. However, staff reported twice the rate of addressing smoking, alcohol, illegal drugs, sexuality, and contraception compared to young...... patients. Young patients reported that smoking, alcohol, illegal drugs, sexuality, and contraception were addressed significantly more at adult clinics in comparison to pediatric clinics. After controlling for age, gender and duration of illness, according to young patients, adjusted odds ratios...

  12. Three Alternative Symbol-Lock Detectors

    Science.gov (United States)

    Shihabi, Mazen M.; Hinedi, Sami M.; Shah, Biren N.

    1993-01-01

    Three symbol-lock detectors proposed as alternatives in advanced receivers processing non-return-to-zero binary data signals. Two perform operations similar to those of older square-law and absolute-value types. However, integrals computed during nonoverlapping symbol periods and, therefore, only one integrator needed in each such detector. Proposed detectors simpler, but performances worse because noises in overlapping samples correlated, whereas noises in nonoverlapping samples not correlated. Third detector is signal-power-estimator type. Signal integrated during successive half symbol cycles, and therefore only one integrator needed. Half-cycle integrals multiplied to eliminate effect of symbol polarity, and products accumulated during M-cycle observation period to smooth out estimate of signal power. If estimated signal power exceeds threshold, delta, then lock declared.

  13. Traumatic knee extension deficit (the locked knee)

    DEFF Research Database (Denmark)

    Helmark, I C; Neergaard, K; Krogsgaard, M R

    2007-01-01

    In the present study we investigated the validity of magnetic resonance imaging (MRI) and arthroscopy in knees with acute, traumatic extension deficit (the "locked knee"), and evaluated whether arthroscopy of knees with no mechanical pathology could be avoided by MRI evaluation. The study consisted...... of 50 patients who had an acute, traumatic extension deficit of the knee. All patients were submitted to MRI prior to arthroscopy. Following MRI and surgery, standardized forms were filled out, attempting to objectify the findings. The orthopaedic surgeon was not aware of the MRI result prior to surgery....... Evaluating MRI, all grade-3 meniscal lesions were considered able to cause a mechanical block as well as acute partial or total anterior cruciate ligament (ACL)-ruptures. ACL-ruptures with an old appearance were not considered able to cause locking. Assuming that arthroscopy was the gold standard...

  14. Mode-locking via dissipative Faraday instability.

    Science.gov (United States)

    Tarasov, Nikita; Perego, Auro M; Churkin, Dmitry V; Staliunas, Kestutis; Turitsyn, Sergei K

    2016-08-09

    Emergence of coherent structures and patterns at the nonlinear stage of modulation instability of a uniform state is an inherent feature of many biological, physical and engineering systems. There are several well-studied classical modulation instabilities, such as Benjamin-Feir, Turing and Faraday instability, which play a critical role in the self-organization of energy and matter in non-equilibrium physical, chemical and biological systems. Here we experimentally demonstrate the dissipative Faraday instability induced by spatially periodic zig-zag modulation of a dissipative parameter of the system-spectrally dependent losses-achieving generation of temporal patterns and high-harmonic mode-locking in a fibre laser. We demonstrate features of this instability that distinguish it from both the Benjamin-Feir and the purely dispersive Faraday instability. Our results open the possibilities for new designs of mode-locked lasers and can be extended to other fields of physics and engineering.

  15. Sheep head frame validation for CT and MRI studies

    Directory of Open Access Journals (Sweden)

    marco trovatelli

    2017-05-01

    Full Text Available Abstract   Introductions Aim of EDEN 2020 project’s Milestone 5 is the development of a steerable catheter for CED system in glioblastoma therapy. The VET group is involved in realization and validation of the proper animal model. Materials and methods In this part of the study two fresh sheep’s head from the local slaughter were used. The heads were located into an ad hoc Frame system based on anatomical measures and CT images, producted by Renishaw plc partner in this project. The frame was adapted and every components were checked for the ex vivo validation tests. CT imaging was taken in Lodi at Università degli studi di Milano, Facoltà di Medicina Veterinaria, with CT scanner and MRI imaging was taken in La Cittadina, Cremona Results System validation was approved by the ex vivo trial. The frame system doesn’t compromise the imaging acquisition in MRI and CT systems. Every system components are functional to their aims. Discussion The Frame system is adapted to the sheep head. It is composed by elements able to lock the head during the imaging acquisition. Frame system is characterized by a support base helpings the animals to keep the head straight forward during imaging time, under general anesthesia. The design of these device support the airways anatomy, avoiding damaging or obstruction of airflows during anesthesia period. The role of elements like mouth bar and ovine head pins is to lock the head in a stable position during imaging acquisition; fixing is guaranteed by V shape head pins, that are arranged against the zygomatic arches. Lateral compression forces to the cranium, and the V shape pins avoid the vertical shifting of the head and any kind of rotations. (fig. 1

  16. Cases requiring increased number of repositioning maneuvers in benign paroxysmal positional vertigo

    Directory of Open Access Journals (Sweden)

    Mukadder Korkmaz

    Full Text Available ABSTRACT INTRODUCTION: Benign paroxysmal positional vertigo (BPPV is a clinical syndrome that is proposed to be caused by dislocated utricular debris into semicircular canals. Although the majority of patients are treated by one or two repositioning maneuvers, some of the patients need repeated maneuvers for relief. OBJECTIVE: The goal of this study was to investigate the factors associated with patients with benign paroxysmal positional vertigo who required multiple repositioning procedures for treatment. METHODS: Data were obtained from the clinical records of 153 patients diagnosed with benign paroxysmal positional vertigo. Patients were treated by repositioning maneuvers. Demographic data and the factors including age, sex, canal type, duration of symptoms, comorbidities and number of repositioning maneuvers for relief were documented for statistical analysis. RESULTS: Age, sex, canal type and the duration of symptoms had no impact on the number of maneuvers. The most common comorbidity was spine problems. Hypertension was the only comorbidity that significantly associated with increased number of maneuvers. CONCLUSION: The presence of hypertension is a risk factor for repeated maneuvers in benign paroxysmal positional vertigo treatment. Physicians should be aware of the increased probability of repeated repositioning maneuvers in these group of patients. The role of comorbidities and vascular factors need to be further clarified in the course of benign paroxysmal positional vertigo.

  17. The effects of betahistine in addition to epley maneuver in posterior canal benign paroxysmal positional vertigo.

    Science.gov (United States)

    Guneri, Enis Alpin; Kustutan, Ozge

    2012-01-01

    The purpose of this study is to evaluate the effects of betahistine in addition to Epley maneuver on the quality of life of patients with posterior semicircular canal benign paroxysmal positional vertigo (BPPV) of the canalithiasis type. Double-blind, randomized, controlled clinical trial. Academic university hospital. Seventy-two patients were enrolled in the study. The first group was treated with Epley maneuver only. The second group received placebo drug 2 times daily for 1 week in addition to Epley maneuver, and the third group received 24 mg betahistine 2 times daily for 1 week in addition to Epley maneuver. The effectiveness of the treatments was assessed in each group as well as between them by analyzing and comparing data of 4 different vertigo symptom scales. Epley maneuver, alone or combined with betahistine or placebo, was found to be very effective with a primary success rate of 86.2%. The symptoms were significantly reduced in group 3 patients overall, and those patients younger or older than 50 years of age who had hypertension, with symptom onset <1 month, and with attack duration of less than a minute did significantly better with the combination of betahistine 48 mg daily. Betahistine in addition to Epley maneuver is more effective than Epley maneuver alone or combined with placebo with regard to improvement of symptoms in certain patients. However, future clinical studies covering more patients to investigate the benefit of medical treatments in addition to Epley maneuver are needed.

  18. Cases requiring increased number of repositioning maneuvers in benign paroxysmal positional vertigo.

    Science.gov (United States)

    Korkmaz, Mukadder; Korkmaz, Hakan

    2016-01-01

    Benign paroxysmal positional vertigo (BPPV) is a clinical syndrome that is proposed to be caused by dislocated utricular debris into semicircular canals. Although the majority of patients are treated by one or two repositioning maneuvers, some of the patients need repeated maneuvers for relief. The goal of this study was to investigate the factors associated with patients with benign paroxysmal positional vertigo who required multiple repositioning procedures for treatment. Data were obtained from the clinical records of 153 patients diagnosed with benign paroxysmal positional vertigo. Patients were treated by repositioning maneuvers. Demographic data and the factors including age, sex, canal type, duration of symptoms, comorbidities and number of repositioning maneuvers for relief were documented for statistical analysis. Age, sex, canal type and the duration of symptoms had no impact on the number of maneuvers. The most common comorbidity was spine problems. Hypertension was the only comorbidity that significantly associated with increased number of maneuvers. The presence of hypertension is a risk factor for repeated maneuvers in benign paroxysmal positional vertigo treatment. Physicians should be aware of the increased probability of repeated repositioning maneuvers in these group of patients. The role of comorbidities and vascular factors need to be further clarified in the course of benign paroxysmal positional vertigo. Copyright © 2015 Associação Brasileira de Otorrinolaringologia e Cirurgia Cérvico-Facial. Published by Elsevier Editora Ltda. All rights reserved.

  19. 32 CFR 552.38 - Acquisition of maneuver agreements for Army commanders.

    Science.gov (United States)

    2010-07-01

    ... Real Estate and Interest Therein § 552.38 Acquisition of maneuver agreements for Army commanders. (a... specific areas desired for use. (b) Real estate coverage. Real estate coverage will be in the form of agreements with landowners, granting the right to conduct maneuvers at a given time or periodically. Short...

  20. Closeup of STS-26 Discovery, OV-103, orbital maneuvering system (OMS) leak

    Science.gov (United States)

    1988-01-01

    Closeup of STS-26 Discovery, Orbiter Vehicle (OV) 103, orbital maneuvering system (OMS) reaction control system (RCS) nitrogen tetroxide gas leak was captured by a Cobra borescope and displayed on a video monitor. The borescope has a miniature videocamera at the end of a flexible rubber tube and is able to be maneuvered into other inaccessible locations.

  1. Applying Dynamical Systems Theory to Optimize Libration Point Orbit Stationkeeping Maneuvers for WIND

    Science.gov (United States)

    Brown, Jonathan M.; Petersen, Jeremy D.

    2014-01-01

    NASA's WIND mission has been operating in a large amplitude Lissajous orbit in the vicinity of the interior libration point of the Sun-Earth/Moon system since 2004. Regular stationkeeping maneuvers are required to maintain the orbit due to the instability around the collinear libration points. Historically these stationkeeping maneuvers have been performed by applying an incremental change in velocity, or (delta)v along the spacecraft-Sun vector as projected into the ecliptic plane. Previous studies have shown that the magnitude of libration point stationkeeping maneuvers can be minimized by applying the (delta)v in the direction of the local stable manifold found using dynamical systems theory. This paper presents the analysis of this new maneuver strategy which shows that the magnitude of stationkeeping maneuvers can be decreased by 5 to 25 percent, depending on the location in the orbit where the maneuver is performed. The implementation of the optimized maneuver method into operations is discussed and results are presented for the first two optimized stationkeeping maneuvers executed by WIND.

  2. Quantum locking of mirrors in interferometers.

    Science.gov (United States)

    Courty, Jean-Michel; Heidmann, Antoine; Pinard, Michel

    2003-02-28

    We show that quantum noise in very sensitive interferometric measurements such as gravitational-wave detectors can be drastically modified by quantum feedback. We present a new scheme based on active control to lock the motion of a mirror to a reference mirror at the quantum level. This simple technique allows one to reduce quantum effects of radiation pressure and to greatly enhance the sensitivity of the detection.

  3. Dither Cavity Length Controller with Iodine Locking

    Directory of Open Access Journals (Sweden)

    Lawson Marty

    2016-01-01

    Full Text Available A cavity length controller for a seeded Q-switched frequency doubled Nd:YAG laser is constructed. The cavity length controller uses a piezo-mirror dither voltage to find the optimum length for the seeded cavity. The piezo-mirror dither also dithers the optical frequency of the output pulse. [1]. This dither in optical frequency is then used to lock to an Iodine absorption line.

  4. Programmable Self-Locking Origami Mechanical Metamaterials.

    Science.gov (United States)

    Fang, Hongbin; Chu, Shih-Cheng A; Xia, Yutong; Wang, Kon-Well

    2018-04-01

    Developing mechanical metamaterials with programmable properties is an emerging topic receiving wide attention. While the programmability mainly originates from structural multistability in previously designed metamaterials, here it is shown that nonflat-foldable origami provides a new platform to achieve programmability via its intrinsic self-locking and reconfiguration capabilities. Working with the single-collinear degree-4 vertex origami tessellation, it is found that each unit cell can self-lock at a nonflat configuration and, therefore, possesses wide design space to program its foldability and relative density. Experiments and numerical analyses are combined to demonstrate that by switching the deformation modes of the constituent cell from prelocking folding to postlocking pressing, its stiffness experiences a sudden jump, implying a limiting-stopper effect. Such a stiffness jump is generalized to a multisegment piecewise stiffness profile in a multilayer model. Furthermore, it is revealed that via strategically switching the constituent cells' deformation modes through passive or active means, the n-layer metamaterial's stiffness is controllable among 2 n target stiffness values. Additionally, the piecewise stiffness can also trigger bistable responses dynamically under harmonic excitations, highlighting the metamaterial's rich dynamic performance. These unique characteristics of self-locking origami present new paths for creating programmable mechanical metamaterials with in situ controllable mechanical properties. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. [Tibiotalocalcaneal arthrodesis using a humeral locking plate].

    Science.gov (United States)

    Cabrera Méndez, M P; Gamba, C; Hernández, E; Molano, J; Andrade, J C

    2016-01-01

    To describe the results of tibiotalocalcáneal arthrodesis (TTC) using a humeral locking plate. A retrospective, observational study was conducted between January 2007 and December 2013 in the Hospital Militar Central de Bogotá. The study included patients with symptomatic osteoarthritis diagnosed clinically and radiologically, and who underwent TTC arthrodesis using a humeral locking plate with a minimum follow up of 6 months. The total number patients was 35, of whom 7 (20%) were women and 28 (80%) men, with a mean age 36.3 years (19.77). 74% with post-traumatic arthritis, most of them secondary to gunshot wounds and fragmentation weapons, and neuropathic in 20%. An autogenous graft was used in 13 cases, and 14 cases using both, with a mean consolidation time of 4.37 months. Complications include, delayed union in 3 cases, and surgical site infection in 4. The postoperative functionality (AOFAS) mean was 66.7/100 points, with a score of 2.35 on a visual analogue pain scale. TTC arthrodesis using a humeral locking plate is a suitable option for fixing this type of arthrodesis, with a low rate of complications, and postoperative results that revealed satisfactory improvement in pain and consolidation. Copyright © 2015 SECOT. Published by Elsevier Espana. All rights reserved.

  6. Self-locking degree-4 vertex origami structures.

    Science.gov (United States)

    Fang, Hongbin; Li, Suyi; Wang, K W

    2016-11-01

    A generic degree-4 vertex (4-vertex) origami possesses one continuous degree-of-freedom for rigid folding, and this folding process can be stopped when two of its facets bind together. Such facet-binding will induce self-locking so that the overall structure stays at a pre-specified configuration without additional locking elements or actuators. Self-locking offers many promising properties, such as programmable deformation ranges and piecewise stiffness jumps, that could significantly advance many adaptive structural systems. However, despite its excellent potential, the origami self-locking features have not been well studied, understood, and used. To advance the state of the art, this research conducts a comprehensive investigation on the principles of achieving and harnessing self-locking in 4-vertex origami structures. Especially, for the first time, this study expands the 4-vertex structure construction from single-component to dual-component designs and investigates their self-locking behaviours. By exploiting various tessellation designs, this research discovers that the dual-component designs offer the origami structures with extraordinary attributes that the single-component structures do not have, which include the existence of flat-folded locking planes, programmable locking points and deformability. Finally, proof-of-concept experiments investigate how self-locking can effectively induce piecewise stiffness jumps. The results of this research provide new scientific knowledge and a systematic framework for the design, analysis and utilization of self-locking origami structures for many potential engineering applications.

  7. Platelet injectors for Space Shuttle orbit maneuvering engine

    Science.gov (United States)

    Kahl, R. C.; Labotz, R. J.; Bassham, L. B.

    1974-01-01

    The Space Shuttle Orbit Maneuvering Subsystem Rocket Engine employs a platelet element injector concept. This injector has demonstrated 316-sec vacuum specific impulse performance under simulated altitude conditions when tested with a milled slot/electroformed nickel close-out regenerative chamber and a full 71 area ratio nozzle. To date, over 300 altitude engine tests and 300 stability bomb tests have demonstrated stable, erosion free operation with this concept to test durations of 150 seconds. The injector and chamber also meet the reusable requirements of the shuttle with a cycle life capability in excess of 1000 cycles. An extensive altitude restart program has also demonstrated OMS-engine operation over large variations in the burn and coast times with helium saturated propellants.

  8. Space shuttle orbital maneuvering engine platelet injector program

    Science.gov (United States)

    1975-01-01

    A platelet-face injector for the fully reusable orbit maneuvering system OMS on the space shuttle was evaluated as a means of obtaining additional design margin and low cost. Performance, heat transfer, and combustion stability were evaluated over the anticipated range of OMS operating conditions. The effects of acoustic cavity configuration on combustion stability, including cavity depth, open area, inlet contour, and other parameters, were investigated using sea level bomb tests. Prototype injector and chamber behavior was evaluated for a variety of conditions; these tests examined the effects of film cooling, helium saturated propellants, chamber length, inlet conditions, and operating point, on performance, heat transfer and engine transient behavior. Helium bubble ingestion into both propellant circuits was investigated, as was chugging at low pressure operation, and hot and cold engine restart with and without a purge.

  9. Helicopter Acoustic Flight Test with Altitude Variation and Maneuvers

    Science.gov (United States)

    Watts, Michael E.; Greenwood, Eric; Sim, Ben; Stephenson, James; Smith, Charles D.

    2016-01-01

    A cooperative flight test campaign between NASA and the U.S. Army was performed from September 2014 to February 2015. The purposes of the testing were to: investigate the effects of altitude variation on noise generation, investigate the effects of gross weight variation on noise generation, establish the statistical variability in acoustic flight testing of helicopters, and characterize the effects of transient maneuvers on radiated noise for a medium-lift utility helicopter. This test was performed at three test sites (0, 4000, and 7000 feet above mean sea level) with two aircraft (AS350 SD1 and EH-60L) tested at each site. This report provides an overview of the test, documents the data acquired and describes the formats of the stored data.

  10. Sequential Probability Ratio Test for Spacecraft Collision Avoidance Maneuver Decisions

    Science.gov (United States)

    Carpenter, J. Russell; Markley, F. Landis

    2013-01-01

    A document discusses sequential probability ratio tests that explicitly allow decision-makers to incorporate false alarm and missed detection risks, and are potentially less sensitive to modeling errors than a procedure that relies solely on a probability of collision threshold. Recent work on constrained Kalman filtering has suggested an approach to formulating such a test for collision avoidance maneuver decisions: a filter bank with two norm-inequality-constrained epoch-state extended Kalman filters. One filter models the null hypotheses that the miss distance is inside the combined hard body radius at the predicted time of closest approach, and one filter models the alternative hypothesis. The epoch-state filter developed for this method explicitly accounts for any process noise present in the system. The method appears to work well using a realistic example based on an upcoming, highly elliptical orbit formation flying mission.

  11. Non-Toxic Orbital Maneuvering System Engine Development

    Science.gov (United States)

    Green, Christopher; Claflin, Scott; Maeding, Chris; Butas, John

    1999-01-01

    Recent results using the Aestus engine operated with LOx/ethanol propellant are presented. An experimental program at Rocketdyne Propulsion and Power is underway to adapt this engine for the Boeing Reusable Space Systems Division non-toxic Orbital Maneuvering System/Reaction control System (OMS/RCS) system. Daimler-Chrysler Aerospace designed the Aestus as an nitrogen tetroxide/monomethyl hydrazine (NTO/MMH) upper-stage engine for the Ariane 5. The non-toxic OMS/RCS system's preliminary design requires a LOx/ethanol (O2/C2H5OH) engine that operates with a mixture ratio of 1.8, a specific impulse of 323 seconds, and fits within the original OMS design envelope. This paper describes current efforts to meet these requirements including, investigating engine performance using LOx/ethanol, developing the en-ine system sizing package, and meeting the vehicle operation parameters. Data from hot-fire testing are also presented and discussed.

  12. Behavior learning in differential games and reorientation maneuvers

    Science.gov (United States)

    Satak, Neha

    method is the Direct Approximation of Value Function (DAVF) method. In this method, unlike the CSR method, the player formulates an objective function for the opponent but does not formulates a strategy directly; rather, indirectly the player assumes that the opponent is playing optimally. Thus, a value function satisfying the HJB equation corresponding to the opponent's cost function exists. The DAVF method finds an approximate solution for the value function based on previous observations of the opponent's control. The approximate solution to the value function is then used to predict the opponent's future behavior. Game examples in which only a single player is learning its opponent's behavior are simulated. Subsequently, examples in which both players in a two-player game are learning each other's behavior are simulated. In the second part of this research, a reorientation control maneuver for a spinning spacecraft will be developed. This will aid the application of behavior learning and differential games concepts to the specific scenario involving multiple spinning spacecraft. An impulsive reorientation maneuver with coasting will be analytically designed to reorient the spin axis of the spacecraft using a single body fixed thruster. Cooperative maneuvers of multiple spacecraft optimizing fuel and relative orientation will be designed. Pareto optimality concepts will be used to arrive at mutually agreeable reorientation maneuvers for the cooperating spinning spacecraft.

  13. Mars Exploration Rovers Launch Performance and TCM-1 Maneuver Design

    Science.gov (United States)

    Kangas, Julie A.; Potts, Christopher L.; Raofi, Behzad

    2004-01-01

    The Mars Exploration Rover (MER) project successfully landed two identical rovers on Mars in order to remotely conduct geologic investigations, including characterization of rocks and soils that may hold clues to past water activity. Two landing sites, Gusev crater and Meridiani Planum, were selected out of nearly 200 candidate sites after balancing science returns and flight system engineering and safety. Precise trajectory targeting and control was necessary to achieve the atmospheric entry requirements for the selected landing sites within the flight system constraints. This paper discusses the expected and achieved launch vehicle performance and the impacts of that performance on the first Trajectory Correction Maneuver (TCM-1) while maintaining targeting flexibility in accommodating additional project concerns about landing site safety and possible in-flight retargeting to alternate landing sites.

  14. Propulsive maneuver design for the Mars Exploration Rover mission

    Science.gov (United States)

    Potts, Christopher L.; Kangas, Julie A.; Raofi, Behzad

    2006-01-01

    Starting from approximately 150 candidate Martian landing sites, two distinct sites have been selected for further investigation by sophisticated rovers. The two rovers, named 'Spirit' and 'Opportunity', begin the surface mission respectively to Gusec Crater and Meridiani Planum in January 2004. the rovers are essentially robotic geologists, sent on a mission to research for evidence in the rocks and soil pertaining to the historical presence of water and the ability to possibly sustain life. Before this scientific search can commence, precise trajectory targeting and control is necessary to achieve the entry requirements for the selected landing sites within the constraints of the flight system. The maneuver design challenge is to meet or exceed these requirements while maintaining the necessary design flexibility to accommodate additional project concerns. Opportunities to improve performance and reduce risk based on trajectory control characteristics are also evaluated.

  15. Nuclear space power systems for orbit raising and maneuvering

    International Nuclear Information System (INIS)

    Buden, D.; Sullivan, J.A.

    1984-01-01

    Reference is made to recent studies which have shown that direct thrust nuclear rockets for routine orbit raising and near-earth space tug missions are probably not cost-effective. The need for additional trade-off studies and comparisons of direct-thrust nuclear systems with chemical systems to clarify the role of nuclear rockets in missions requiring rapid orbit maneuvering is stressed. Attention is confined here to nuclear electric propulsion considerations. Low-mass nuclear power plants are constructed to optimize nuclear electric propulsion systems. Electric power levels from 100 kilowatts to as much as several megawatts are desirable. The goals for the power plant specific mass are 20-30 kg/kW at the lower powers to 2-4 kg/kW at the higher powers

  16. Head Impact Laboratory (HIL)

    Data.gov (United States)

    Federal Laboratory Consortium — The HIL uses testing devices to evaluate vehicle interior energy attenuating (EA) technologies for mitigating head injuries resulting from head impacts during mine/...

  17. Influence of head posture on the visual acuity of children with nystagmus

    Directory of Open Access Journals (Sweden)

    Ana Carla Ramos Vieira da Costa

    2014-01-01

    Full Text Available Purpose: Evaluate the relationship between the postural alignment of the head and possible interference in the view of children. Methods: We evaluated 11 children between 2 and 7 years of age of both sexes, with the visually impaired, who had nystagmus and head lock position. The test Lea Grating Acuity Test® was used to collect measurements of visual acuity. This applied on two occasions: with and without postural alignment of the head. For reliability of the postural alignment of the head, the slopes were measured by Fisiologic® software. Results: The children had a poorer performance after physiological postural alignment. This poor performance is possible due to loss of position lock nystagmus to gain postural alignment, said to be ideal. Postural compensations were observed, and sharply increased eyestrain. Conclusion: The pursuit of traditional postural alignment affect the visual response of children with visual impairments.

  18. Identification and risk estimation of movement strategies during cutting maneuvers.

    Science.gov (United States)

    David, Sina; Komnik, Igor; Peters, Markus; Funken, Johannes; Potthast, Wolfgang

    2017-12-01

    Approximately 70% of anterior cruciate ligament (ACL) injuries occur in non-contact situations during cutting and landing maneuvers. Parameters such as footstrike patterns and trunk orientation were found to influence ACL relevant knee loading, however, the relationship between the whole body movement and injury risk is debated. This study identifies whole body movement strategies that increase injury risk, and provides training recommendations to reduce this risk or enable a save return to sports after injury. Experimental cross-sectional study design. Three dimensional movement analysis was carried out to investigate 50 participants performing anticipated 90° cutting maneuvers. To identify and characterize movement strategies, footstrike pattern, knee valgus moment, knee internal rotation moment, angle of attack, shoulder and pelvis axis were analyzed using statistical parametric mapping. Three different movement strategies were identified. One strategy included rearfoot striking in combination with a relatively upright body position which generated higher knee joint loads than the second strategy, forefoot striking in combination with more backwards leaning and pre-rotation of the trunk towards the new movement direction. A third strategy combined forefoot striking with less preorientation which increased the ACL relevant knee joint load compared to the second strategy. The identified movement strategies clearly pre-determine the injury risk during non-contact situations with the third strategy as the most unfavorable one. Compared to the study of isolated parameters, the analysis of the whole body movement allowed for detailed separation of more risky from less risky cutting strategies. These results give practical recommendations for the prevention of ACL injury. Copyright © 2017 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

  19. Characteristics of helmet or knit cap use in head injury of snowboarders.

    Science.gov (United States)

    Fukuda, Osamu; Hirashima, Yutaka; Origasa, Hideki; Endo, Shunro

    2007-11-01

    The rate of head injury is 1.86-6 times higher for snowboarding than for skiing. Detailed data about the usefulness of a helmet or knit cap for protecting against serious head injuries have not been reported. The present study evaluated the use of a helmet or knit cap for preventing head injuries. Questionnaire data were collected from 1,190 consecutive patients in a hospital during the 1999/2000-2002/2003 winter seasons at Uonuma ski resort, Niigata, Japan. Patients were divided into the helmet, knit cap, and no cap groups. Upper technical level was highest and jumping as the cause of injury was most frequent in the helmet group. After adjustment for other confounders, there was a significant negative association between the occurrence of serious head injury during snowboarding and female sex (adjusted odds ratio 0.55, 95% confidence interval 0.421-0.718, p jumping (adjusted odds ratio 2.25, 95% confidence interval 1.48-3.43, p = 0.0001). Among snowboarding maneuvers, only jumping showed a significant negative association between wearing of a helmet or knit cap and the occurrence of serious head injury (p = 0.036). Snowboarders who wear helmets might attempt dangerous maneuvers causing injuries. Wearing of a helmet or knit cap protected against serious head injuries on jumping. Every snowboarder should wear a helmet or knit cap on jumping to prevent head injury.

  20. Heading and head injuries in soccer.

    Science.gov (United States)

    Kirkendall, D T; Jordan, S E; Garrett, W E

    2001-01-01

    In the world of sports, soccer is unique because of the purposeful use of the unprotected head for controlling and advancing the ball. This skill obviously places the player at risk of head injury and the game does carry some risk. Head injury can be a result of contact of the head with another head (or other body parts), ground, goal post, other unknown objects or even the ball. Such impacts can lead to contusions, fractures, eye injuries, concussions or even, in rare cases, death. Coaches, players, parents and physicians are rightly concerned about the risk of head injury in soccer. Current research shows that selected soccer players have some degree of cognitive dysfunction. It is important to determine the reasons behind such deficits. Purposeful heading has been blamed, but a closer look at the studies that focus on heading has revealed methodological concerns that question the validity of blaming purposeful heading of the ball. The player's history and age (did they play when the ball was leather and could absorb significant amounts of water), alcohol intake, drug intake, learning disabilities, concussion definition and control group use/composition are all factors that cloud the ability to blame purposeful heading. What does seem clear is that a player's history of concussive episodes is a more likely explanation for cognitive deficits. While it is likely that the subconcussive impact of purposeful heading is a doubtful factor in the noted deficits, it is unknown whether multiple subconcussive impacts might have some lingering effects. In addition, it is unknown whether the noted deficits have any affect on daily life. Proper instruction in the technique is critical because if the ball contacts an unprepared head (as in accidental head-ball contacts), the potential for serious injury is possible. To further our understanding of the relationship of heading, head injury and cognitive deficits, we need to: learn more about the actual impact of a ball on the

  1. Frequency-Locked Detector Threshold Setting Criteria Based on Mean-Time-To-Lose-Lock (MTLL) for GPS Receivers.

    Science.gov (United States)

    Jin, Tian; Yuan, Heliang; Zhao, Na; Qin, Honglei; Sun, Kewen; Ji, Yuanfa

    2017-12-04

    Frequency-locked detector (FLD) has been widely utilized in tracking loops of Global Positioning System (GPS) receivers to indicate their locking status. The relation between FLD and lock status has been seldom discussed. The traditional PLL experience is not suitable for FLL. In this paper, the threshold setting criteria for frequency-locked detector in the GPS receiver has been proposed by analyzing statistical characteristic of FLD output. The approximate probability distribution of frequency-locked detector is theoretically derived by using a statistical approach, which reveals the relationship between probabilities of frequency-locked detector and the carrier-to-noise ratio ( C / N ₀) of the received GPS signal. The relationship among mean-time-to-lose-lock (MTLL), detection threshold and lock probability related to C / N ₀ can be further discovered by utilizing this probability. Therefore, a theoretical basis for threshold setting criteria in frequency locked loops for GPS receivers is provided based on mean-time-to-lose-lock analysis.

  2. Propulsion System and Orbit Maneuver Integration in CubeSats: Trajectory Control Strategies Using Micro Ion Propulsion

    Science.gov (United States)

    Hudson, Jennifer; Martinez, Andres; Petro, Andrew

    2015-01-01

    The Propulsion System and Orbit Maneuver Integration in CubeSats project aims to solve the challenges of integrating a micro electric propulsion system on a CubeSat in order to perform orbital maneuvers and control attitude. This represents a fundamentally new capability for CubeSats, which typically do not contain propulsion systems and cannot maneuver far beyond their initial orbits.

  3. The strength of polyaxial locking interfaces of distal radius plates.

    Science.gov (United States)

    Hoffmeier, Konrad L; Hofmann, Gunther O; Mückley, Thomas

    2009-10-01

    Currently available polyaxial locking plates represent the consequent enhancement of fixed-angle, first-generation locking plates. In contrast to fixed-angle locking plates which are sufficiently investigated, the strength of the new polyaxial locking options has not yet been evaluated biomechanically. This study investigates the mechanical strength of single polyaxial interfaces of different volar radius plates. Single screw-plate interfaces of the implants Palmar 2.7 (Königsee Implantate und Instrumente zur Osteosynthese GmbH, Allendorf, Germany), VariAx (Stryker Leibinger GmbH & Co. KG, Freiburg, Germany) und Viper (Integra LifeSciences Corporation, Plainsboro, NJ, USA) were tested by cantilever bending. The strength of 0 degrees, 10 degrees and 20 degrees screw locking angle was obtained during static and dynamic loading. The Palmar 2.7 interfaces showed greater ultimate strength and fatigue strength than the interfaces of the other implants. The strength of the VariAx interfaces was about 60% of Palmar 2.7 in both, static and dynamic loading. No dynamic testing was applied to the Viper plate because of its low ultimate strength. By static loading, an increase in screw locking angle caused a reduction of strength for the Palmar 2.7 and Viper locking interfaces. No influence was observed for the VariAx locking interfaces. During dynamic loading; angulation had no influence on the locking strength of Palmar 2.7. However, reduction of locking strength with increasing screw angulation was observed for VariAx. The strength of the polyaxial locking interfaces differs remarkably between the examined implants. Depending on the implant an increase of the screw locking angle causes a reduction of ultimate or fatigue strength, but not in all cases a significant impact was observed.

  4. Delay differential equations for mode-locked semiconductor lasers.

    Science.gov (United States)

    Vladimirov, Andrei G; Turaev, Dmitry; Kozyreff, Gregory

    2004-06-01

    We propose a new model for passive mode locking that is a set of ordinary delay differential equations. We assume a ring-cavity geometry and Lorentzian spectral filtering of the pulses but do not use small gain and loss and weak saturation approximations. By means of a continuation method, we study mode-locking solutions and their stability. We find that stable mode locking can exist even when the nonlasing state between pulses becomes unstable.

  5. Analysis of peer-to-peer locking of magnetrons

    International Nuclear Information System (INIS)

    Pengvanich, P.; Lau, Y. Y.; Cruz, E.; Gilgenbach, R. M.; Hoff, B.; Luginsland, J. W.

    2008-01-01

    The condition for mutual, or peer-to-peer, locking of two magnetrons is derived. This condition reduces to Adler's classical phase-locking condition in the limit where one magnetron becomes the ''master'' and the other becomes the ''slave.'' The formulation is extended to the peer-to-peer locking of N magnetrons, under the assumption that the electromagnetic coupling among the N magnetrons is modeled by an N-port network.

  6. An Evaluation of Coarse-Grained Locking for Multicore Microkernels

    OpenAIRE

    Elphinstone, Kevin; Zarrabi, Amirreza; Danis, Adrian; Shen, Yanyan; Heiser, Gernot

    2016-01-01

    The trade-off between coarse- and fine-grained locking is a well understood issue in operating systems. Coarse-grained locking provides lower overhead under low contention, fine-grained locking provides higher scalability under contention, though at the expense of implementation complexity and re- duced best-case performance. We revisit this trade-off in the context of microkernels and tightly-coupled cores with shared caches and low inter-core migration latencies. We evaluate performance on ...

  7. A general method for closed-loop inverse simulation of helicopter maneuver flight

    Directory of Open Access Journals (Sweden)

    Wei WU

    2017-12-01

    Full Text Available Maneuverability is a key factor to determine whether a helicopter could finish certain flight missions successfully or not. Inverse simulation is commonly used to calculate the pilot controls of a helicopter to complete a certain kind of maneuver flight and to assess its maneuverability. A general method for inverse simulation of maneuver flight for helicopters with the flight control system online is developed in this paper. A general mathematical describing function is established to provide mathematical descriptions of different kinds of maneuvers. A comprehensive control solver based on the optimal linear quadratic regulator theory is developed to calculate the pilot controls of different maneuvers. The coupling problem between pilot controls and flight control system outputs is well solved by taking the flight control system model into the control solver. Inverse simulation of three different kinds of maneuvers with different agility requirements defined in the ADS-33E-PRF is implemented based on the developed method for a UH-60 helicopter. The results show that the method developed in this paper can solve the closed-loop inverse simulation problem of helicopter maneuver flight with high reliability as well as efficiency. Keywords: Closed-loop, Flying quality, Helicopters, Inverse simulation, Maneuver flight

  8. Dynamic sensor tasking and IMM EKF estimation for tracking impulsively maneuvering satellites

    Science.gov (United States)

    Lace, Arthur A.

    In order to efficiently maintain space situational awareness, care must be taken to optimally allocate expensive observation resources. In most situations the available sensors capable of tracking spacecraft have their time split between many different monitoring responsibilities. Tracking maneuvering spacecraft can be especially difficult as the schedule of maneuvers may not be known and will often throw off previous orbital models. Effectively solving this tasking problem is an ongoing focus of research in the area of space situational awareness. Most methods of automated tasking do not make use of interacting multiple model extended Kalman filter techniques to better track satellites during maneuvers. This paper proposes a modification to a Fisher information gain and estimated state covariance based sensor tasking method to take maneuver probability and multiple model dynamics into account. By incorporating the probabilistic maneuvering model, sensor tasking can be improved during satellite maneuvers using constrained resources. The proposed methods are verified through the use of numerical simulations with multiple maneuvering satellites and both orbital and ground-based sensors.

  9. Head Trauma: First Aid

    Science.gov (United States)

    First aid Head trauma: First aid Head trauma: First aid By Mayo Clinic Staff Most head trauma involves injuries that are minor and don't require ... 21, 2015 Original article: http://www.mayoclinic.org/first-aid/first-aid-head-trauma/basics/ART-20056626 . Mayo ...

  10. Minimum Propellant Low-Thrust Maneuvers near the Libration Points

    Science.gov (United States)

    Marinescu, A.; Dumitrache, M.

    The impulse technique certainly can bring the vehicle on orbits around the libration points or close to them. The question that aries is, by what means can the vehicle arrive in such cases at the libration points? A first investigation carried out in this paper can give an answer: the use of the technique of low-thrust, which, in addition, can bring the vehicle from the libration points near to or into orbits around these points. This aspect is considered in this present paper where for the applications we have considered the transfer for orbits of the equidistant point L4 and of the collinear point L2, from Earth-moon system. This transfer maneuver can be used to insertion one satellite on libration points orbits. In Earth- moon system the points L 4 and L 5 because an vehicle in on of the equidistant points in quite stable and remains in its vicinity of perturbed, have potential interest for the establishment of transporder satellite for interplanetary tracking. In contrast an vehicle in one of the collinear points is quite instable and it will oscillate along the Earth-moon-axis at increasing amplitude and gradually escape from the libration point. Let use assume that a space vehicle equipped with a low-thrust propulsion is near a libration point L. We consider the planar motion in the restricted frame of the three bodies in the rotating system L, where the Earth-moon distance D=l. The unit of time T is period of the moon's orbit divided by 2 and multiplied by the square root of the quantity one plus the moon/Earth mass ratio, and the unit of mass is the Earth's mass. With these predictions the motion equatios of the vehicle equiped with a low-thrust propulsion installation in the linear approximation near the libration point, have been established. The parameters of the motion at the beginning and the end of these maneuvers are known, the variational problem has been formulated as a Lagrange type problem with fixed extremities. On established the differential

  11. Progress as Compositional Lock-Freedom

    DEFF Research Database (Denmark)

    Carbone, Marco; Dardha, Ornela; Montesi, Fabrizio

    2014-01-01

    A session-based process satisfies the progress property if its sessions never get stuck when it is executed in an adequate context. Previous work studied how to define progress by introducing the notion of catalysers, execution contexts generated from the type of a process. In this paper, we refine...... such definition to capture a more intuitive notion of context adequacy for checking progress. Interestingly, our new catalysers lead to a novel characterisation of progress in terms of the standard notion of lock-freedom. Guided by this discovery, we also develop a conservative extension of catalysers that does...

  12. Locking classical correlations in quantum States.

    Science.gov (United States)

    DiVincenzo, David P; Horodecki, Michał; Leung, Debbie W; Smolin, John A; Terhal, Barbara M

    2004-02-13

    We show that there exist bipartite quantum states which contain a large locked classical correlation that is unlocked by a disproportionately small amount of classical communication. In particular, there are (2n+1)-qubit states for which a one-bit message doubles the optimal classical mutual information between measurement results on the subsystems, from n/2 bits to n bits. This phenomenon is impossible classically. However, states exhibiting this behavior need not be entangled. We study the range of states exhibiting this phenomenon and bound its magnitude.

  13. Advanced frequency synthesis by phase lock

    CERN Document Server

    Egan, William F

    2011-01-01

    "An addendum to the popular Frequency Synthesis by Phase Lock, 2nd ed, this book describes sigma-delta, a frequency synthesis technique that has gained prominence in recent years. In addition, Simulink will be employed extensively to guide the reader. Fractional-n, the still-used forerunner to sigma-delta, is also discussed. Sequences of simulated results allow the reader to gain a deeper understanding while detailed appendices provide information from various stages of development. Simulation models discussed in the chapters that are available online."--Provided by publisher.

  14. Saint Lawrence Seaway Additional Locks Study. Appendices.

    Science.gov (United States)

    1982-07-01

    1790320 1945 2370 27000 LO 710 i...l.I27.121.710.0443 23.00.769 12.229.146 2,3231.503 2.5~06.000 2.239.100 23.760.400 23.019.2002 3.413200 P.. Capita...1955. - ,. XISING EISENHOWER LOCK G ISO Se-s SP*c.--2 2, 13 TIL ANDBDROC ~~~~~~ AREA LIISO9TL AD All b 22 CORPS OF ENGINEERS BUFFAL0 NY RUFFALO DISTR

  15. Short locking time and low jitter phase-locked loop based on slope charge pump control

    International Nuclear Information System (INIS)

    Guo Zhongjie; Liu Youbao; Wu Longsheng; Wang Xihu; Tang Wei

    2010-01-01

    A novel structure of a phase-locked loop (PLL) characterized by a short locking time and low jitter is presented, which is realized by generating a linear slope charge pump current dependent on monitoring the output of the phase frequency detector (PFD) to implement adaptive bandwidth control. This improved PLL is created by utilizing a fast start-up circuit and a slope current control on a conventional charge pump PLL. First, the fast start-up circuit is enabled to achieve fast pre-charging to the loop filter. Then, when the output pulse of the PFD is larger than a minimum value, the charge pump current is increased linearly by the slope current control to ensure a shorter locking time and a lower jitter. Additionally, temperature variation is attenuated with the temperature compensation in the charge pump current design. The proposed PLL has been fabricated in a kind of DSP chip based on a 0.35 μm CMOS process. Comparing the characteristics with the classical PLL, the proposed PLL shows that it can reduce the locking time by 60% with a low peak-to-peak jitter of 0.3% at a wide operation temperature range. (semiconductor integrated circuits)

  16. Low-power wide-locking-range injection-locked frequency divider for OFDM UWB systems

    Energy Technology Data Exchange (ETDEWEB)

    Yin Jiangwei; Li Ning; Zheng Renliang; Li Wei; Ren Junyan, E-mail: lining@fudan.edu.c [State Key Laboratory of ASIC and System, Fudan University, Shanghai 201203 (China)

    2009-05-01

    This paper describes a divide-by-two injection-locked frequency divider (ILFD) for frequency synthesizers as used in multiband orthogonal frequency division multiplexing (OFDM) ultra-wideband (UWB) systems. By means of dual-injection technique and other conventional tuning techniques, such as DCCA and varactor tuning, the divider demonstrates a wide locking range while consuming much less power. The chip was fabricated in the Jazz 0.18 mum RF CMOS process. The measurement results show that the divider achieves a locking range of 4.85 GHz (6.23 to 11.08 GHz) at an input power of 8 dBm. The core circuit without the test buffer consumes only 3.7 mA from a 1.8 V power supply and has a die area of 0.38 x 0.28 mm{sup 2}. The wide locking range combined with low power consumption makes the ILFD suitable for its application in UWB systems.

  17. Low-power wide-locking-range injection-locked frequency divider for OFDM UWB systems

    International Nuclear Information System (INIS)

    Yin Jiangwei; Li Ning; Zheng Renliang; Li Wei; Ren Junyan

    2009-01-01

    This paper describes a divide-by-two injection-locked frequency divider (ILFD) for frequency synthesizers as used in multiband orthogonal frequency division multiplexing (OFDM) ultra-wideband (UWB) systems. By means of dual-injection technique and other conventional tuning techniques, such as DCCA and varactor tuning, the divider demonstrates a wide locking range while consuming much less power. The chip was fabricated in the Jazz 0.18 μm RF CMOS process. The measurement results show that the divider achieves a locking range of 4.85 GHz (6.23 to 11.08 GHz) at an input power of 8 dBm. The core circuit without the test buffer consumes only 3.7 mA from a 1.8 V power supply and has a die area of 0.38 x 0.28 mm 2 . The wide locking range combined with low power consumption makes the ILFD suitable for its application in UWB systems.

  18. Concurrent image-based visual servoing with adaptive zooming for non-cooperative rendezvous maneuvers

    Science.gov (United States)

    Pomares, Jorge; Felicetti, Leonard; Pérez, Javier; Emami, M. Reza

    2018-02-01

    An image-based servo controller for the guidance of a spacecraft during non-cooperative rendezvous is presented in this paper. The controller directly utilizes the visual features from image frames of a target spacecraft for computing both attitude and orbital maneuvers concurrently. The utilization of adaptive optics, such as zooming cameras, is also addressed through developing an invariant-image servo controller. The controller allows for performing rendezvous maneuvers independently from the adjustments of the camera focal length, improving the performance and versatility of maneuvers. The stability of the proposed control scheme is proven analytically in the invariant space, and its viability is explored through numerical simulations.

  19. Statistical study of overvoltages by maneuvering in switches in high voltage using EMTP-RV

    International Nuclear Information System (INIS)

    Dominguez Herrera, Diego Armando

    2013-01-01

    The transient overvoltages produced by maneuvering of switches are studied in a statistical way and through a variation the sequential closing times of switches in networks larger than 230 kV. This study is performed according to time delays and typical deviation ranges, using the tool EMTP- RV (ElectroMagnetic Trasient Program Restructured Version). A conceptual framework related with the electromagnetic transients by maneuver is developed in triphasic switches installed in nominal voltages higher than 230 kV. The methodology established for the execution of statistical studies of overvoltages by switch maneuver is reviewed and evaluated by simulating two fictitious cases in EMTP-RV [es

  20. Head and neck cancer

    International Nuclear Information System (INIS)

    Vogl, S.E.

    1988-01-01

    This book contains 10 chapters. Some of the titles are: Combined Surgical Resection and Irradiation for Head and Neck Cancers; Analysis of Radiation Therapy Oncology Group Head and Neck Database: Identification of Prognostic Factors and the Re-evaluation of American Joint Committee Stages; Combined Modality Approach to Head and Neck Cancer; Induction Combination Chemotherapy of Regionally Advanced Head and Neck Cancer; and Outcome after Complete Remission to Induction Chemotherapy in Head and Neck Cancer

  1. Reconfigurable Braille display with phase change locking

    Science.gov (United States)

    Soule, Cody W.; Lazarus, Nathan

    2016-07-01

    Automatically updated signs and displays for sighted people are common in today’s world. However, there is no cheap, low power equivalent available for the blind. This work demonstrates a reconfigurable Braille cell using the solid-to-liquid phase change of a low melting point alloy as a zero holding power locking mechanism. The device is actuated with the alloy in the liquid state, and is then allowed to solidify to lock the Braille dot in the actuated position. A low-cost manufacturing process is developed that includes molding of a rigid silicone to create pneumatic channels, and bonding of a thin membrane of a softer silicone on the surface for actuation. A plug of Field’s metal (melting point 62 °C) is placed in the pneumatic channels below each Braille dot to create the final device. The device is well suited for low duty cycle operation in applications such as signs, and is able to maintain its state indefinitely without additional power input. The display requires a pneumatic pressure of only 24 kPa for actuation, and reconfiguration has been demonstrated in less than a minute and a half.

  2. Combilift ideal for maneuvering oil and gas equipment

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    2009-07-15

    This article described an innovative forklift that responds to the oil industry's need for a safer, better and easier way to move long tubular products that cannot be carried high in the air. The Gator Jaw is a duplex pipe clamp attachment that secures to the Combilift forklift carriage. The clamp arm can be hydraulically moved upwards to allow the operator full use of the forks without interference from the hold down arm. The Combilift's platform is ideal for maneuvering oil and gas equipment close to the ground. Since it can travel sideways, the length of the load is not critical. The Gator Jaw's unique design makes it possible for one forklift to handle both skids and pallets. The C-Series product extends to the subsea oil and gas industry, which works with long loads such as oil drilling tools and pipe. The benefits include safer product handling, significant space savings, increased productivity and versatile indoor and outdoor use. The machines are available with a fuel-efficient liquefied petroleum gas (LPG) or diesel engine. 1 fig.

  3. Space shuttle orbit maneuvering engine reusable thrust chamber program

    Science.gov (United States)

    Senneff, J. M.

    1975-01-01

    Reusable thrust chamber and injector concepts were evaluated for the space shuttle orbit maneuvering engine (OME). Parametric engine calculations were carried out by computer program for N2O4/amine, LOX/amine and LOX/hydrocarbon propellant combinations for engines incorporating regenerative cooled and insulated columbium thrust chambers. The calculation methods are described including the fuel vortex film cooling method of combustion gas temperature control, and performance prediction. A method of acceptance of a regeneratively cooled heat rejection reduction using a silicone oil additive was also demonstrated by heated tube heat transfer testing. Regeneratively cooled thrust chamber operation was also demonstrated where the injector was characterized for the OME application with a channel wall regenerative thrust chamber. Bomb stability testing of the demonstration chambers/injectors demonstrated recovery for the nominal design of acoustic cavities. Cavity geometry changes were also evaluated to assess their damping margin. Performance and combustion stability was demonstrated of the originally developed 10 inch diameter combustion pattern operating in an 8 inch diameter thrust chamber.

  4. Spacecraft Attitude Tracking and Maneuver Using Combined Magnetic Actuators

    Science.gov (United States)

    Zhou, Zhiqiang

    2010-01-01

    The accuracy of spacecraft attitude control using magnetic actuators only is low and on the order of 0.4-5 degrees. The key reason is that the magnetic torque is two-dimensional and it is only in the plane perpendicular to the magnetic field vector. In this paper novel attitude control algorithms using the combination of magnetic actuators with Reaction Wheel Assembles (RWAs) or other types of actuators, such as thrusters, are presented. The combination of magnetic actuators with one or two RWAs aligned with different body axis expands the two-dimensional control torque to three-dimensional. The algorithms can guarantee the spacecraft attitude and rates to track the commanded attitude precisely. A design example is presented for Nadir pointing, pitch and yaw maneuvers. The results show that precise attitude tracking can be reached and the attitude control accuracy is comparable with RWAs based attitude control. The algorithms are also useful for the RWAs based attitude control. When there are only one or two workable RWAs due to RWA failures, the attitude control system can switch to the control algorithms for the combined magnetic actuators with the RWAs without going to the safe mode and the control accuracy can be maintained.

  5. Development of Strategy Generator for PWRs Core Maneuver

    International Nuclear Information System (INIS)

    Deswandri

    2003-01-01

    Generally, nuclear power plants are utilized for base-load operation. However, if the nuclear capacity constitutes a large fraction of the total electric capacity in a country, the ability of nuclear power plants to perform load following operation is inevitable. In the load following operation, the reactor power is adjusted based on the fluctuation of electric power demand in the grid. That changes of power level can cause unbalance in the reactor, therefore, the control actions should be done during the power maneuvering. In order that the control actions could be effective and efficient, guidance for the reactor operators is needed. Strategy generator refers to a tool which provides guidance for operators as to control actions to be taken. This work developed the strategy generator based on the three concepts of control strategy. By numerical simulation, performance of these three strategies was tested and compared. The simulation result shows the unique characteristic for each strategy and discussion was provided to evaluate the abilities of each strategy in achieving the control targets. (author)

  6. Open Platform for Limit Protection with Carefree Maneuver Applications

    Science.gov (United States)

    Jeram, Geoffrey J.

    2004-01-01

    This Open Platform for Limit Protection guides the open design of maneuver limit protection systems in general, and manned, rotorcraft, aerospace applications in particular. The platform uses three stages of limit protection modules: limit cue creation, limit cue arbitration, and control system interface. A common set of limit cue modules provides commands that can include constraints, alerts, transfer functions, and friction. An arbitration module selects the "best" limit protection cues and distributes them to the most appropriate control path interface. This platform adopts a holistic approach to limit protection whereby it considers all potential interface points, including the pilot's visual, aural, and tactile displays; and automatic command restraint shaping for autonomous limit protection. For each functional module, this thesis guides the control system designer through the design choices and information interfaces among the modules. Limit cue module design choices include type of prediction, prediction mechanism, method of critical control calculation, and type of limit cue. Special consideration is given to the nature of the limit, particularly the level of knowledge about it, and the ramifications for limit protection design, especially with respect to intelligent control methods such as fuzzy inference systems and neural networks.

  7. Spacecraft Attitude Tracking and Maneuver Using Combined Magnetic Actuators

    Science.gov (United States)

    Zhou, Zhiqiang

    2012-01-01

    A paper describes attitude-control algorithms using the combination of magnetic actuators with reaction wheel assemblies (RWAs) or other types of actuators such as thrusters. The combination of magnetic actuators with one or two RWAs aligned with different body axis expands the two-dimensional control torque to three-dimensional. The algorithms can guarantee the spacecraft attitude and rates to track the commanded attitude precisely. A design example is presented for nadir-pointing, pitch, and yaw maneuvers. The results show that precise attitude tracking can be reached and the attitude- control accuracy is comparable with RWA-based attitude control. When there are only one or two workable RWAs due to RWA failures, the attitude-control system can switch to the control algorithms for the combined magnetic actuators with the RWAs without going to the safe mode, and the control accuracy can be maintained. The attitude-control algorithms of the combined actuators are derived, which can guarantee the spacecraft attitude and rates to track the commanded values precisely. Results show that precise attitude tracking can be reached, and the attitude-control accuracy is comparable with 3-axis wheel control.

  8. Tactical approach to maneuvering within the chemical contamination labyrinth

    Energy Technology Data Exchange (ETDEWEB)

    Joseph, T.W. [Department of Energy, Oak Ridge, TN (United States)

    1990-12-31

    The Department of Energy (DOE) recognized the need and accepts the responsibility for understanding the reality and mitigating the consequence of the complex chemical contamination legacy it inherited as well as controlling, reducing, and eliminating extant emissions and effluents. The key to maneuvering through this complicated and multifaceted labyrinth of concerns, from which a meaningful, high quality, and cost-effective restoration/mitigation machine is then set in motions, is the ability to perform accurate, factual, and explicit health and environmental/ecological risk assessments. Likewise, the common denominator for carrying out this essential task is to have access to comprehensive and reliable data of known quality with which to perform those analyses. DOE is committed to identifying the data universe; to technically scrutinize and ensure the quality of that data; to develop efficient and cost-effective means to maximize the handling, utilization, and sharing of that universe; and to undertake those assessments. DOE views this as an effort that can only be accomplished through a merging of the technical excellence that exists within federal and state agencies, academia, and industry. The task at hand is so large that only by integrating that intelligence base can we hope to accomplish the goals of establishing meaningful standards, developing functional and effective solutions, and providing quality guidance at a national scale.

  9. Steering characteristic of an articulated bus under quasi steady maneuvering

    Science.gov (United States)

    Ubaidillah, Setiawan, Budi Agus; Aridharma, Airlangga Putra; Lenggana, Bhre Wangsa; Caesar, Bernardus Placenta Previo

    2018-02-01

    Articulated buses have been being preferred as public transportation modes due to their operational capacity. Therefore, passenger safety must be the priority of this public service vehicle. This research focused on the analytical approach of steering characteristics of an articulated bus when it maneuvered steadily. Such turning condition could be referred as a stability parameter of the bus for preliminary handling assessment. The analytical approach employed kinematics relationship between front and rear bodies as well as steering capabilities. The quasi steady model was developed to determine steering parameters such as turning radius, oversteer, and understeer. The mathematical model was useful for determining both coefficients of understeer and oversteer. The dimension of articulated bus followed a commonly used bus as utilized in Trans Jakarta busses. Based on the simulation, for one minimum center of the body, the turning radius was calculated about 8.8 m and 7.6 m at steady turning speed of 10 km/h. In neutral condition, the minimum road radius should be 6.5 m at 10 km/h and 6.9 m at 40 km/h. For two centers of the body and oversteer condition, the front body has the turning radius of 8.8 m, while, the rear body has the turning radius of 9.8 m at both turning speeds of 40 km/h. The other steering parameters were discussed accordingly.

  10. Tom Bevill Upper Lock Approach, Tennessee-Tombigbee Waterway, Alabama: Hydraulic Navigation Investigation

    National Research Council Canada - National Science Library

    Winkler, Michael

    2003-01-01

    .... The lock is connected to the dam with a 150-ft abutment wall. A strong crosscurrent or outdraft existing in and around the upstream lock entrance causes difficulty for tow traffic navigating the lock...

  11. A safe-repositioning maneuver for the management of benign paroxysmal positional vertigo: Gans vs. Epley maneuver; a randomized comparative clinical trial.

    Science.gov (United States)

    Saberi, Alia; Nemati, Shadman; Sabnan, Salah; Mollahoseini, Fatemeh; Kazemnejad, Ehsan

    2017-08-01

    Benign paroxysmal positional vertigo (BPPV) is the most common cause of peripheral vertigo. Some repositioning maneuvers have been described for its management. The aim of this study was comparing the therapeutic effect of Epley and Gans maneuvers in BPPV. This randomized clinical trial was performed from September to December 2015. 73 patients with true vertigo diagnosed as BPPV enrolled the study. They randomly assigned in quadripartite blocks to modified Epley maneuver group (E) or Gans maneuver group (G). 1 day and 1 week after intervention, the objective and subjective responses to treatment were assessed. Statistical analysis was performed using the Chi-square test and regression model in the SPSS software version 21. Thirty patients enrolled each group with a mean age of 46.9 ± 13.4 (E group) and 46.7 ± 7.5 year (G group). 23.3 % of E group and 26.7 % of G group were men (p = 0.766). In E and G groups in the first day, subjective outcomes revealed 86.7 and 60 % rate of success (p = 0.02); and 86.7 and 56.7 % of patients exhibited objective improvement, respectively (p = 0.01). After 1 week, the subjective and objective outcomes revealed improvement among 70 % of E group and 46.7 % of G group (p = 0.067). The only complication with significant difference was cervical pain with a higher rate in E group (23.3 vs. 0.0 %, p = 0.005). These results revealed the similar long-term efficacy of Epley and Gans maneuver for the treatment of BPPV. Cervical pain was most frequent complication of Epley maneuver.

  12. Efficacy of Epley’s Maneuver in Treating BPPV Patients: A Prospective Observational Study

    Directory of Open Access Journals (Sweden)

    Sushil Gaur

    2015-01-01

    Full Text Available Vertigo and balance disorders are among the most common symptoms encountered in patients who visit ENT outpatient department. This is associated with risk of falling and is compounded in elderly persons with other neurologic deficits and chronic medical problems. BPPV is the most common cause of peripheral vertigo. BPPV is a common vestibular disorder leading to significant morbidity, psychosocial impact, and medical costs. The objective of Epley’s maneuver, which is noninvasive, inexpensive, and easily administered, is to move the canaliths out of the canal to the utricle where they no longer affect the canal dynamics. Our study aims to analyze the response to Epley’s maneuver in a series of patients with posterior canal BPPV and compares the results with those treated exclusively by medical management alone. Even though many studies have been conducted to prove the efficacy of this maneuver, this study reinforces the validity of Epley’s maneuver by comparison with the medical management.

  13. Importance of back blow maneuvers in a 6 month old patient with sudden upper airway obstruction

    Directory of Open Access Journals (Sweden)

    Pinar Gencpinar

    2015-12-01

    Full Text Available Foreign body aspiration in children under four years old is one of the most frequently observed reasons for accident related deaths. It is more common in this age group due to inadequate swallowing functions and exploration of objects with the mouth. The most frequently encountered foreign bodies are food and toy parts. Life threatening complete laryngeal obstruction is rarely observed. Dyspnea, hypersalivation, cough and cyanosis can be seen. The basic and life-saving treatment approach is complete removal of foreign body maneuvers in the sudden onset of total obstruction. Here we report a six-month old male, who ingested a foreign body and was treated with back blow maneuvers successfully. In this case we emphasized the importance of back blow maneuvers. Keywords: Upper airway obstruction, Child, Back blows maneuvers

  14. A Computer Simulation of the System-Wide Effects of Parallel-Offset Route Maneuvers

    Science.gov (United States)

    Lauderdale, Todd A.; Santiago, Confesor; Pankok, Carl

    2010-01-01

    Most aircraft managed by air-traffic controllers in the National Airspace System are capable of flying parallel-offset routes. This paper presents the results of two related studies on the effects of increased use of offset routes as a conflict resolution maneuver. The first study analyzes offset routes in the context of all standard resolution types which air-traffic controllers currently use. This study shows that by utilizing parallel-offset route maneuvers, significant system-wide savings in delay due to conflict resolution of up to 30% are possible. It also shows that most offset resolutions replace horizontal-vectoring resolutions. The second study builds on the results of the first and directly compares offset resolutions and standard horizontal-vectoring maneuvers to determine that in-trail conflicts are often more efficiently resolved by offset maneuvers.

  15. Pulsed Electrogasdynamic Thruster for Attitude Control and Orbit Maneuver, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — A new pulsed electric thruster, named "pulsed electrogasdynamic thruster," for attitude control and orbit maneuver is proposed. In this thruster, propellant gas is...

  16. The application of the random regret minimization model to drivers’ choice of crash avoidance maneuvers

    DEFF Research Database (Denmark)

    Kaplan, Sigal; Prato, Carlo Giacomo

    This study explores the plausibility of regret minimization as behavioral paradigm underlying the choice of crash avoidance maneuvers. Alternatively to previous studies that considered utility maximization, this study applies the random regret minimization (RRM) model while assuming that drivers ...

  17. The application of the random regret minimization model to drivers’ choice of crash avoidance maneuvers

    DEFF Research Database (Denmark)

    Kaplan, Sigal; Prato, Carlo Giacomo

    2012-01-01

    This study explores the plausibility of regret minimization as behavioral paradigm underlying the choice of crash avoidance maneuvers. Alternatively to previous studies that considered utility maximization, this study applies the random regret minimization (RRM) model while assuming that drivers ...

  18. Determination of the optimal conditions for inclination maneuvers using a Swing-by

    Science.gov (United States)

    Moura, O.; Celestino, C. C.; Prado, A. F. B. A.

    2018-05-01

    The search for methods to reduce the fuel consumption in orbital transfers is something relevant and always current in astrodynamics. Therefore, the maneuvers assisted by the gravity, also called Swing-by maneuvers, can be an advantageous option to save fuel. The proposal of the present research is to explore the influence of some parameters in a Swing-by of an artificial satellite orbiting a planet with one of the moons of this mother planet, with the goal of changing the inclination of the artificial satellite around the main body of the system. The fuel consumption of this maneuver is compared with the required consumption to perform the same change of inclination using the classical approach of impulsive maneuvers.

  19. Development of a Ground Vehicle Maneuver Ontology to Support the Common Operational Picture

    National Research Council Canada - National Science Library

    Richmond, Paul W; Blais, Curtis L; Goerger, Niki C

    2006-01-01

    .... This paper describes both the Mobility-COP, from which warfighters can assess the ability of forces to maneuver effectively under multiple environmental and tactical conditions, and a formal ontology...

  20. The Rapier or the Club: The Relationship between Attrition and Maneuver Warfare

    National Research Council Canada - National Science Library

    Springman, Jeffrey A

    2006-01-01

    ...? This project compares the relationship between attrition and maneuver warfare. The study considers whether there are times when wars of attrition should be fought, and whether there are conditions that force wars of attrition...

  1. Scaling laws for mode lockings in circle maps

    International Nuclear Information System (INIS)

    Cvitanovic, P.; Shraiman, B.; Soederberg, B.

    1985-06-01

    The self-similar structure of mode lockings for circle maps is studied by means of the associated Farey trees. We investigate numerically several classes of scaling relations implicit in the Farey organization of mode lockings and discuss the extent to which they lead to universal scaling laws. (orig.)

  2. 30 CFR 57.12068 - Locking transformer enclosures.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Locking transformer enclosures. 57.12068 Section 57.12068 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND... Electricity Surface Only § 57.12068 Locking transformer enclosures. Transformer enclosures shall be kept...

  3. Investigation on Locking and Pulling Modes in Analog Frequency Dividers

    Directory of Open Access Journals (Sweden)

    Antonio Buonomo

    2013-01-01

    Full Text Available We compare the main analytical results available to estimate the locking range, which is the key figure-of-merit of LC frequency dividers based on the injection locking phenomenon. Starting from the classical result by Adler concerning injection-locked oscillators, we elucidate the merits and the shortcomings of the different approaches to study injection-locked frequency dividers, with particular emphasis on divider-by-2. In particular, we show the potential of a perturbation approach which enables a more complete analysis of frequency dividers, making it possible to calculate not only the amplitude and the phase of the locked oscillation, but also the region where it exists and is stable, which defines the locking region. Finally, we analyze the dynamical behaviour of the dividers in the vicinity of the boundary of the locking region, showing that there exists a border region where the occurrence of the locking or the pulling operation mode is possible, depending on the initial conditions of the system.

  4. Lock-In Agreements in Venture Capital Backed UK IPOs

    NARCIS (Netherlands)

    Espenlaub, S.; Goergen, M.; Khurshed, A.; Renneboog, L.D.R.

    2002-01-01

    This paper examines the impact of venture-capital backing of UK companies issuing shares at flotation on the characteristics of the lock-in agreements entered into by the existing shareholders, and on the abnormal returns realised around the expiry of the directors' lock-in agreements.The study

  5. Aktuaalsetest tendentsidest elektroakustilise muusika alal Eestis / Gerhard Lock

    Index Scriptorium Estoniae

    Lock, Gerhard, 1978-

    2007-01-01

    Elektroakustilise muusika lähiajaloost, elektroakustilist muusikat viljelevatest Eesti heliloojatest. Age Hirv, Raun Juurikas, Liis Jürgens, Andrus Kallastu, Tatjana Kozlova, Ülo Krigul, Margo Kõlar, Märt-Matis Lill, Gerhard Lock, Hans-Gunter Lock, Malle Maltis, Jüri Reinvere, Mart Siimer, Mirjam Tally, Toomas Trass, Lauri-Dag Tüür oma muusikast

  6. Phase-locking regimes of photonic crystal nanocavity laser arrays

    DEFF Research Database (Denmark)

    Skovgård, Troels Suhr; Kristensen, Philip Trøst; Mørk, Jesper

    2011-01-01

    -difference time-domain calculations, the typical coupling strength is extracted for realistic structures. Phase-locking regimes are identified, and their stability with respect to parameter variation is investigated. The results suggest that quantum well devices are not well suited for phase-locked nanocavity...

  7. ELB-trees - Efficient Lock-free B+trees

    DEFF Research Database (Denmark)

    Bonnichsen, Lars Frydendal; Karlsson, Sven; Probst, Christian W.

    2014-01-01

    As computer systems scale in the number of processors, data structures with good parallel performance become increasingly important. Lock-free data structures promise improved parallel performance at the expense of higher complexity and sequential execution time.We present ELBtrees, a new lock-fr...

  8. Use of Lung Opening Maneuver in Patients with Acute Respiratory Failure After Cardiosurgical Operations

    Directory of Open Access Journals (Sweden)

    A. A. Yeremenko

    2006-01-01

    Full Text Available Postoperative respiratory failure is a most common complication and a main cause of postoperative death. The lung opening maneuver is a most effective method of respiratory therapy for this syndrome.Objective. To evaluate the impact of recruiting maneuver on gas exchange parameters, the biomechanical properties of the lung, and hemodynamic parameters. To determine whether the lung opening maneuver can be fully performed in patients undergoing cardiac surgery.Materials and methods. The study covered 19 patients aged 53 to 70 years who had postoperative failure. The indication for the recruiting maneuver was a decrease in the oxygenation index below 250 mm Hg during assisted ventilation (AV with FiO2>0.5, an inspiratory-expira-tory phase ratio of 1:1 to 3:1, and a positive end-expiratory pressure of 5—10 cm H2O.Results. A decrease in the oxygenation index to 139±36 mm Hg was observed before the recruiting maneuver was applied. Cd;n. averaged 41.1±8.4 ml/cm H2O. After use of the recruiting maneuver, there were increases in the oxygenation index up to 371±121 mm Hg and in Cd;n. up to 64.3±10 ml/cm H2O in all the patients. When the recruiting maneuver was employed, 14 patients were observed to have elevated blood pressures corrected with a vasopressor. One patient developed pneumothorax that was drained in proper time.Conclusion. The application of the lung opening maneuver leads to a considerable improvement of gas exchange parameters and lung mechanical properties.

  9. CFD Analysis of a Maneuvering F/A-18E Super Hornet

    Science.gov (United States)

    2016-10-12

    tools for aircraft, ships, and radio - frequency antenna design and analysis. The resulting program is called the Computational Research and Engineering...accurately predicting the forces and moments on the F/A-18E Super Hornet while performing several complicated maneuvers. Past F/A-18E computational studies... predicting the forces and moments on the F/A-18E Super Hornet while performing several complicated maneuvers. Past F/A-18E computational studies have

  10. Know Before You Do: Anticipating Maneuvers via Learning Temporal Driving Models

    Science.gov (United States)

    2015-04-01

    features/index.htm. Accessed: 2014-09-30. [3] Google self driving car . http://en.wikipedia.org/wiki/ Google driverless car . Accessed: 2014-10-11. [4...and outside the car , GPS, and speed information, with lane and driving maneuver annotations. II. RELATED WORK Assistive features for vehicles . Recent...made driving safer over the last decade. They prepare vehicles for unsafe road conditions and alert drivers if they perform a dangerous maneuver

  11. Cases requiring increased number of repositioning maneuvers in benign paroxysmal positional vertigo

    OpenAIRE

    Korkmaz, Mukadder; Korkmaz, Hakan

    2016-01-01

    ABSTRACT INTRODUCTION: Benign paroxysmal positional vertigo (BPPV) is a clinical syndrome that is proposed to be caused by dislocated utricular debris into semicircular canals. Although the majority of patients are treated by one or two repositioning maneuvers, some of the patients need repeated maneuvers for relief. OBJECTIVE: The goal of this study was to investigate the factors associated with patients with benign paroxysmal positional vertigo who required multiple repositioning proced...

  12. A general method for closed-loop inverse simulation of helicopter maneuver flight

    OpenAIRE

    Wei WU

    2017-01-01

    Maneuverability is a key factor to determine whether a helicopter could finish certain flight missions successfully or not. Inverse simulation is commonly used to calculate the pilot controls of a helicopter to complete a certain kind of maneuver flight and to assess its maneuverability. A general method for inverse simulation of maneuver flight for helicopters with the flight control system online is developed in this paper. A general mathematical describing function is established to provid...

  13. Phase locking of vortex cores in two coupled magnetic nanopillars

    Directory of Open Access Journals (Sweden)

    Qiyuan Zhu

    2014-11-01

    Full Text Available Phase locking dynamics of the coupled vortex cores in two identical magnetic spin valves induced by spin-polarized current are studied by means of micromagnetic simulations. Our results show that the available current range of phase locking can be expanded significantly by the use of constrained polarizer, and the vortices undergo large orbit motions outside the polarization areas. The effects of polarization areas and dipolar interaction on the phase locking dynamics are studied systematically. Phase locking parameters extracted from simulations are discussed by theoreticians. The dynamics of vortices influenced by spin valve geometry and vortex chirality are discussed at last. This work provides deeper insights into the dynamics of phase locking and the results are important for the design of spin-torque nano-oscillators.

  14. Spatially resolved detection of mutually locked Josephson junctions in arrays

    International Nuclear Information System (INIS)

    Keck, M.; Doderer, T.; Huebener, R.P.; Traeuble, T.; Dolata, R.; Weimann, T.; Niemeyer, J.

    1997-01-01

    Mutual locking due to the internal coupling in two-dimensional arrays of Josephson junctions was investigated. The appearance of Shapiro steps in the current versus voltage curve of a coupled on-chip detector junction is used to indicate coherent oscillations in the array. A highly coherent state is observed for some range of the array bias current. By scanning the array with a low-power electron beam, mutually locked junctions remain locked while the unlocked junctions generate a beam-induced additional voltage drop at the array. This imaging technique allows the detection of the nonlocked or weakly locked Josephson junctions in a (partially) locked array state. copyright 1997 American Institute of Physics

  15. Novel control algorithm of braking energy regeneration system for an electric vehicle during safety–critical driving maneuvers

    International Nuclear Information System (INIS)

    Lv, Chen; Zhang, Junzhi; Li, Yutong; Yuan, Ye

    2015-01-01

    Highlights: • Models of an electric vehicle with regenerative braking system (RBS) are built. • Control algorithm of RBS under safety–critical driving maneuvers is proposed. • Simulations and HIL tests of the proposed strategy are conducted. • Performance improvement of vehicle’s mean deceleration is up to 13.89%. • Test results verify the feasibility and effectiveness of the proposed method. - Abstract: This paper mainly focuses on control algorithm of the braking energy regeneration system of an electric bus under safety–critical driving situations. With the aims of guaranteeing vehicle stability in various types of tyre–road adhesion conditions, based on the characteristics of electrified powertrain, a novel control algorithm of regenerative braking system is proposed for electric vehicles during anti-lock braking procedures. First, the models of vehicle dynamics and main components including braking energy regenerative system of the case-study electric bus are built in MATLAB/Simulink. Then, based on the phase-plane method, the optimal brake torque is calculated for ABS control of vehicle. Next, a novel allocation strategy, wherein the target optimal brake torque is divided into two parts that are handled separately by the regenerative and friction brakes, is developed. Simulations of the proposed control strategy are conducted based on system models built using MATLAB/Simulink. The simulation results demonstrate that the developed strategy enables improved control in terms of vehicle stability and braking performance under different emergency driving conditions. To further verify the synthesized control algorithm, hardware-in-the-loop tests are also performed. The experimental results validate the simulation data and verify the feasibility and effectiveness of the developed control algorithm.

  16. Biomechanical in vitro assessment of screw augmentation in locked plating of proximal humerus fractures.

    Science.gov (United States)

    Röderer, Götz; Scola, Alexander; Schmölz, Werner; Gebhard, Florian; Windolf, Markus; Hofmann-Fliri, Ladina

    2013-10-01

    Proximal humerus fracture fixation can be difficult because of osteoporosis making it difficult to achieve stable implant anchorage in the weak bone stock even when using locking plates. This may cause implant failure requiring revision surgery. Cement augmentation has, in principle, been shown to improve stability. The aim of this study was to investigate whether augmentation of particular screws of a locking plate aimed at a region of low bone quality is effective in improving stability in a proximal humerus fracture model. Twelve paired human humerus specimens were included. Quantitative computed tomography was performed to determine bone mineral density (BMD). Local bone quality in the direction of the six proximal screws of a standard locking plate (PHILOS, Synthes) was assessed using mechanical means (DensiProbe™). A three-part fracture model with a metaphyseal defect was simulated and fixed with the plate. Within each pair of humeri the two screws aimed at the region of the lowest bone quality according to the DensiProbe™ were augmented in a randomised manner. For augmentation, 0.5 ml of bone cement was injected in a screw with multiple outlets at its tip under fluoroscopic control. A cyclic varus-bending test with increasing upper load magnitude was performed until failure of the screw-bone fixation. The augmented group withstood significantly more load cycles. The correlation of BMD with load cycles until failure and BMD with paired difference in load cycles to failure showed that augmentation could compensate for a low BMD. The results demonstrate that augmentation of screws in locked plating in a proximal humerus fracture model is effective in improving primary stability in a cyclic varus-bending test. The augmentation of two particular screws aimed at a region of low bone quality within the humeral head was almost as effective as four screws with twice the amount of bone cement. Screw augmentation combined with a knowledge of the local bone quality

  17. Monolithic Hybrid and Passive Mode-Locked 40GHz Quantum Dot Laser Diodes

    DEFF Research Database (Denmark)

    Thompson, M. G.; Larsson, David; Rae, A. R.

    2006-01-01

    For the first time hybrid and passive mode-locking jitter performance is investigated in 40GHz quantum-dot mode-locked lasers. Record low passive mode-locking jitter of 219fs is presented, along with promising hybrid mode-locking results of 124fs.......For the first time hybrid and passive mode-locking jitter performance is investigated in 40GHz quantum-dot mode-locked lasers. Record low passive mode-locking jitter of 219fs is presented, along with promising hybrid mode-locking results of 124fs....

  18. Locking of intrinsic angular momentum in collision complexes

    International Nuclear Information System (INIS)

    Berengolts, Alexander.

    1995-04-01

    A concept of locking of the intrinsic angular momentum of a fragment of a collision complex to a body-fixed axis is widely used in the description of heavy-particle dynamics. The aim of this work is to provide a semiclassical description of the locking phenomenon which occur in diatomic and three atomic collision complexes. The first part of this work is devoted to the semiclassical study of the locking of the electronic angular momentum that occurs in slow collisions of two atoms, one in the spherically symmetric state and the other in state with j= 1. Here we calculate explicitly the complete locking matrix for different types of interatomic interactions. The elements of this matrix directly enter into the semiclassical expression for the different cross sections of polarized atoms. Limitations to the notion of the the locking radius and slipping probability are discussed in connection with the steepness of the interaction. Numerical calculations confirm analytical result: the optimal criterion for determination of the locking radius is a condition for the accumulated phase difference between two molecular states. Analytical expressions are suggested for the locking angle and the slipping probability. Implication of the locking approximation for calculation of the quasiclassical scattering matrix is discussed. The second part considers the locking of the rotational angular momentum of a diatom in the decomposition of a triatomic complexes. We discuss here cases J = 1,2,3 and 4, but restrict ourselves to calculation of the so-called dynamic orientation of the diatomic fragment. The letter represents one of the characteristics of the locking matrix which in principle can be measured experimentally. The orientation is created as a result of the interplay between the adiabatic interaction in the atom- diatom exit channel and the rotationally non adiabatic coupling in the perturbed rotor region

  19. Heterogeneous Silicon III-V Mode-Locked Lasers

    Science.gov (United States)

    Davenport, Michael Loehrlein

    Mode-locked lasers are useful for a variety of applications, such as sensing, telecommunication, and surgical instruments. This work focuses on integrated-circuit mode-locked lasers: those that combine multiple optical and electronic functions and are manufactured together on a single chip. While this allows production at high volume and lower cost, the true potential of integration is to open applications for mode-locked laser diodes where solid state lasers cannot fit, either due to size and power consumption constraints, or where small optical or electrical paths are needed for high bandwidth. Unfortunately, most high power and highly stable mode-locked laser diode demonstrations in scientific literature are based on the Fabry-Perot resonator design, with cleaved mirrors, and are unsuitable for use in integrated circuits because of the difficulty of producing integrated Fabry-Perot cavities. We use silicon photonics and heterogeneous integration with III-V gain material to produce the most powerful and lowest noise fully integrated mode-locked laser diode in the 20 GHz frequency range. If low noise and high peak power are required, it is arguably the best performing fully integrated mode-locked laser ever demonstrated. We present the design methodology and experimental pathway to realize a fully integrated mode-locked laser diode. The construction of the device, beginning with the selection of an integration platform, and proceeding through the fabrication process to final optimization, is presented in detail. The dependence of mode-locked laser performance on a wide variety of design parameters is presented. Applications for integrated circuit mode-locked lasers are also discussed, as well as proposed methods for using integration to improve mode-locking performance to beyond the current state of the art.

  20. Shareholder Lock-In Contracts : Share Price and Trading Volume Effects at the Lock-In Expiry

    NARCIS (Netherlands)

    Angenandt, P.P.; Goergen, M.; Renneboog, L.D.R.

    2005-01-01

    This paper unveils the diversity in lock-in agreements of firms listed on the Nouveau Marche stock exchange in France.We give the main economic reasons why shareholders adopt lock-in agreements that are more stringent than legally required.We relate the abnormal returns and the abnormal volume at

  1. A unified flight control methodology for a compound rotorcraft in fundamental and aerobatic maneuvering flight

    Science.gov (United States)

    Thorsen, Adam

    This study investigates a novel approach to flight control for a compound rotorcraft in a variety of maneuvers ranging from fundamental to aerobatic in nature. Fundamental maneuvers are a class of maneuvers with design significance that are useful for testing and tuning flight control systems along with uncovering control law deficiencies. Aerobatic maneuvers are a class of aggressive and complex maneuvers with more operational significance. The process culminating in a unified approach to flight control includes various control allocation studies for redundant controls in trim and maneuvering flight, an efficient methodology to simulate non-piloted maneuvers with varying degrees of complexity, and the setup of an unconventional control inceptor configuration along with the use of a flight simulator to gather pilot feedback in order to improve the unified control architecture. A flight path generation algorithm was developed to calculate control inceptor commands required for a rotorcraft in aerobatic maneuvers. This generalized algorithm was tailored to generate flight paths through optimization methods in order to satisfy target terminal position coordinates or to minimize the total time of a particular maneuver. Six aerobatic maneuvers were developed drawing inspiration from air combat maneuvers of fighter jet aircraft: Pitch-Back Turn (PBT), Combat Ascent Turn (CAT), Combat Descent Turn (CDT), Weaving Pull-up (WPU), Combat Break Turn (CBT), and Zoom and Boom (ZAB). These aerobatic maneuvers were simulated at moderate to high advance ratios while fundamental maneuvers of the compound including level accelerations/decelerations, climbs, descents, and turns were investigated across the entire flight envelope to evaluate controller performance. The unified control system was developed to allow controls to seamlessly transition between manual and automatic allocations while ensuring that the axis of control for a particular inceptor remained constant with flight

  2. Head injury - first aid

    Science.gov (United States)

    ... medlineplus.gov/ency/article/000028.htm Head injury - first aid To use the sharing features on this page, ... a concussion can range from mild to severe. First Aid Learning to recognize a serious head injury and ...

  3. Computed Tomography (CT) -- Head

    Medline Plus

    Full Text Available ... the head uses special x-ray equipment to help assess head injuries, severe headaches, dizziness, and other ... aneurysm, bleeding, stroke and brain tumors. It also helps your doctor to evaluate your face, sinuses, and ...

  4. Computed Tomography (CT) -- Head

    Medline Plus

    Full Text Available ... for Brain Tumors Radiation Therapy for Head and Neck Cancer Others American Stroke Association National Stroke Association ... Computer Tomography (CT) Safety During Pregnancy Head and Neck Cancer X-ray, Interventional Radiology and Nuclear Medicine ...

  5. Computed Tomography (CT) -- Head

    Medline Plus

    Full Text Available ... When the image slices are reassembled by computer software, the result is a very detailed multidimensional view ... Safety Images related to Computed Tomography (CT) - Head Videos related to Computed Tomography (CT) - Head Sponsored by ...

  6. Computed Tomography (CT) -- Head

    Medline Plus

    Full Text Available ... the limitations of CT Scanning of the Head? What is CT Scanning of the Head? Computed tomography, ... than regular radiographs (x-rays). top of page What are some common uses of the procedure? CT ...

  7. An elevator for locked drilling pipes

    Energy Technology Data Exchange (ETDEWEB)

    Gurbanov, R.S.; Abbasov, E.M.; Ismailov, A.A.; Mamedov, Yu.S.; Safarov, A.A.

    1983-01-01

    An elevator is proposed, which includes a body with a door. To reduce the probability of gas shows in a well with high speed lowering and lifting of the column of locked drilling pipes through providing the possibility of feeding a drilling mud in this case into the mine, the elevator is equipped with a pneumatic cylinder with a two way hollow rod, on one face of which a sealing element is mounted for sealing the drilling pipe and on the other, an adapter for feeding the drilling mud. The rod is linked with the sleeve of the pneumatic cylinder, which is rigidly linked with the body with the capability of axial movement without rotation.

  8. Gapless Color-Flavor-Locked Quark Matter

    DEFF Research Database (Denmark)

    Alford, Mark; Kouvaris, Christoforos; Rajagopal, Krishna

    2004-01-01

    In neutral cold quark matter that is sufficiently dense that the strange quark mass M_s is unimportant, all nine quarks (three colors; three flavors) pair in a color-flavor locked (CFL) pattern, and all fermionic quasiparticles have a gap. We argue that as a function of decreasing quark chemical...... potential mu or increasing M_s, there is a quantum phase transition from the CFL phase to a new ``gapless CFL phase'' in which only seven quasiparticles have a gap. The transition occurs where M_s^2/mu is approximately equal to 2*Delta, with Delta the gap parameter. Gapless CFL, like CFL, leaves unbroken...... a linear combination Qtilde of electric and color charges, but it is a Qtilde-conductor with a nonzero electron density. These electrons and the gapless quark quasiparticles make the low energy effective theory of the gapless CFL phase and, consequently, its astrophysical properties are qualitatively...

  9. Manned maneuvering unit applications for automated rendezvous and capture

    Science.gov (United States)

    Brehm, Donald L.; Cuseo, John A.; Lenda, Joseph A.; Ray, Lex; Whitsett, C. Edward

    Automated Rendezvous and Capture (AR&C) is an important technology to multiple National Aeronautics and Space Administration (NASA) programs and centers. The recent Johnson Spacecraft Center (JSC) AR&C Quality Function Deployment (QFD) has listed on-orbit demonstration of related technologies as a near term priority. Martin Marietta has been evaluating use of the Manned Maneuvering Unit (MMU) for a low cost near term on-orbit demonstration of AR&C technologies such as control algorithms, sensors, and processors as well as system level performance. The MMU Program began in 1979 as the method of repairing the Space Shuttle (STS) Thermal Protection System (the tiles). The units were not needed for this task, but were successfully employed during three Shuttle flights in 1984: a test flight was flown in in February as proof of concept, in April the MMU participated in the Solar Max Repair Mission, and in November the MMU's returned to space to successfully rescue the two errant satellites, Westar and Palapa. In the intervening years, the MMU simulator and MMU Qualification Test Unit (QTU) have been used for Astronaut training and experimental evaluations. The Extra-Vehicular Activities (EVA) Retriever has used the QTU, in an unmanned form, as a free-flyer on the Johnson Space Center (JSC) Precision Air Bearing Floor (PABF). Currently, the MMU is undergoing recertification for flight. The two flight units were removed from storage in September, 1991 and evaluation tests were performed. The tests demonstrated that the units are in good shape with no discrepancies that would preclude further use. The Return to Flight effort is currently clearing up recertification issues and evaluating the design against the present Shuttle environments.

  10. Dynamics of Tidally Locked, Ultrafast Rotating Atmospheres

    Science.gov (United States)

    Tan, Xianyu; Showman, Adam P.

    2017-10-01

    Tidally locked gas giants, which exhibit a novel regime of day-night thermal forcing and extreme stellar irradiation, are typically in several-day orbits, implying slow rotation and a modest role for rotation in the atmospheric circulation. Nevertheless, there exist a class of gas-giant, highly irradiated objects - brown dwarfs orbiting white dwarfs in extremely tight orbits - whose orbital and hence rotation periods are as short as 1-2 hours. Spitzer phase curves and other observations have already been obtained for this fascinating class of objects, which raise fundamental questions about the role of rotation in controlling the circulation. So far, most modeling studies have investigated rotation periods exceeding a day, as appropriate for typical hot Jupiters. In this work we investigate the dynamics of tidally locked atmospheres in shorter rotation periods down to about two hours. With increasing rotation rate (decreasing rotation period), we show that the width of the equatorial eastward jet decreases, consistent with the narrowing of wave-mean-flow interacting region due to decrease of the equatorial deformation radius. The eastward-shifted equatorial hot spot offset decreases accordingly, and the westward-shifted hot regions poleward of the equatorial jet associated with Rossby gyres become increasingly distinctive. At high latitudes, winds becomes weaker and more geostrophic. The day-night temperature contrast becomes larger due to the stronger influence of rotation. Our simulated atmospheres exhibit small-scale variability, presumably caused by shear instability. Unlike typical hot Jupiters, phase curves of fast-rotating models show an alignment of peak flux to secondary eclipse. Our results have important implications for phase curve observations of brown dwarfs orbiting white dwarfs in ultra tight orbits.

  11. An Analytical Solution for Yaw Maneuver Optimization on the International Space Station and Other Orbiting Space Vehicles

    Science.gov (United States)

    Dobrinskaya, Tatiana

    2015-01-01

    This paper suggests a new method for optimizing yaw maneuvers on the International Space Station (ISS). Yaw rotations are the most common large maneuvers on the ISS often used for docking and undocking operations, as well as for other activities. When maneuver optimization is used, large maneuvers, which were performed on thrusters, could be performed either using control moment gyroscopes (CMG), or with significantly reduced thruster firings. Maneuver optimization helps to save expensive propellant and reduce structural loads - an important factor for the ISS service life. In addition, optimized maneuvers reduce contamination of the critical elements of the vehicle structure, such as solar arrays. This paper presents an analytical solution for optimizing yaw attitude maneuvers. Equations describing pitch and roll motion needed to counteract the major torques during a yaw maneuver are obtained. A yaw rate profile is proposed. Also the paper describes the physical basis of the suggested optimization approach. In the obtained optimized case, the torques are significantly reduced. This torque reduction was compared to the existing optimization method which utilizes the computational solution. It was shown that the attitude profiles and the torque reduction have a good match for these two methods of optimization. The simulations using the ISS flight software showed similar propellant consumption for both methods. The analytical solution proposed in this paper has major benefits with respect to computational approach. In contrast to the current computational solution, which only can be calculated on the ground, the analytical solution does not require extensive computational resources, and can be implemented in the onboard software, thus, making the maneuver execution automatic. The automatic maneuver significantly simplifies the operations and, if necessary, allows to perform a maneuver without communication with the ground. It also reduces the probability of command

  12. Computed Tomography (CT) -- Head

    Medline Plus

    Full Text Available ... Physician Resources Professions Site Index A-Z Computed Tomography (CT) - Head Computed tomography (CT) of the head uses special x-ray ... What is CT Scanning of the Head? Computed tomography, more commonly known as a CT or CAT ...

  13. Migration from full-head mask to "open-face" mask for immobilization of patients with head and neck cancer.

    Science.gov (United States)

    Li, Guang; Lovelock, D Michael; Mechalakos, James; Rao, Shyam; Della-Biancia, Cesar; Amols, Howard; Lee, Nancy

    2013-09-06

    To provide an alternative device for immobilization of the head while easing claustrophobia and improving comfort, an "open-face" thermoplastic mask was evaluated using video-based optical surface imaging (OSI) and kilovoltage (kV) X-ray radiography. A three-point thermoplastic head mask with a precut opening and reinforced strips was developed. After molding, it provided sufficient visible facial area as the region of interest for OSI. Using real-time OSI, the head motion of ten volunteers in the new mask was evaluated during mask locking and 15minutes lying on the treatment couch. Using a nose mark with reference to room lasers, forced head movement in open-face and full-head masks (with a nose hole) was compared. Five patients with claustrophobia were immobilized with open-face masks, set up using OSI and kV, and treated in 121 fractions, in which 61 fractions were monitored during treatment using real-time OSI. With the open-face mask, head motion was found to be 1.0 ± 0.6 mm and 0.4° ± 0.2° in volunteers during the experiment, and 0.8 ± 0.3 mm and 0.4° ± 0.2° in patients during treatment. These agree with patient motion calculated from pre-/post-treatment OSI and kV data using different anatomical landmarks. In volunteers, the head shift induced by mask-locking was 2.3 ± 1.7 mm and 1.8° ± 0.6°, and the range of forced movements in the open-face and full-head masks were found to be similar. Most (80%) of the volunteers preferred the open-face mask to the full-head mask, while claustrophobic patients could only tolerate the open-face mask. The open-face mask is characterized for its immobilization capability and can immobilize patients sufficiently (< 2 mm) during radiotherapy. It provides a clinical solution to the immobilization of patients with head and neck (HN) cancer undergoing radiotherapy, and is particularly beneficial for claustrophobic patients. This new open-face mask is readily adopted in radiotherapy clinic as a superior alternative to

  14. 77 FR 71590 - Lock+TM

    Science.gov (United States)

    2012-12-03

    ..., 50-foot-deep frame module fitted with a trash rack and containing 10 low-head bulb turbines each... electronically via the Internet. See 18 CFR 385.2001(a)(1)(iii) and the instructions on the Commission's Web site... Commission's Web site at http://www.ferc.gov/docs-filing/elibrary.asp . Enter the docket number (P-13500-002...

  15. Injection locking of optomechanical oscillators via acoustic waves

    Science.gov (United States)

    Huang, Ke; Hossein-Zadeh, Mani

    2018-04-01

    Injection locking is a powerful technique for synchronization of oscillator networks and controlling the phase and frequency of individual oscillators using similar or other types of oscillators. Here, we present the first demonstration of injection locking of a radiation-pressure driven optomechanical oscillator (OMO) via acoustic waves. As opposed to previously reported techniques (based on pump modulation or direct application of a modulated electrostatic force), injection locking of OMO via acoustic waves does not require optical power modulation or physical contact with the OMO and it can easily be implemented on various platforms. Using this approach we have locked the phase and frequency of two distinct modes of a microtoroidal silica OMO to a piezoelectric transducer (PZT). We have characterized the behavior of the injection locked OMO with three acoustic excitation configurations and showed that even without proper acoustic impedance matching the OMO can be locked to the PZT and tuned over 17 kHz with only -30 dBm of RF power fed to the PZT. The high efficiency, simplicity and scalability of the proposed approach paves the road toward a new class of photonic systems that rely on synchronization of several OMOs to a single or multiple RF oscillators with applications in optical communication, metrology and sensing. Beyond its practical applications, injection locking via acoustic waves can be used in fundamental studies in quantum optomechanics where thermal and optical isolation of the OMO are critical.

  16. Key-lock colloids in a nematic liquid crystal.

    Science.gov (United States)

    Silvestre, Nuno M; Tasinkevych, M

    2017-01-01

    The Landau-de Gennes free energy is used to study theoretically the effective interaction of spherical "key" and anisotropic "lock" colloidal particles. We assume identical anchoring properties of the surfaces of the key and of the lock particles, and we consider planar degenerate and perpendicular anchoring conditions separately. The lock particle is modeled as a spherical particle with a spherical dimple. When such a particle is introduced into a nematic liquid crystal, it orients its dimple at an oblique angle θ_{eq} with respect to the far field director n_{∞}. This angle depends on the depth of the dimple. Minimization results show that the free energy of a pair of key and lock particles exhibits a global minimum for the configuration when the key particle is facing the dimple of the lock colloidal particle. The preferred orientation ϕ_{eq} of the key-lock composite doublet relative to n_{∞} is robust against thermal fluctuations. The preferred orientation θ_{eq}^{(2)} of the dimple particle in the doublet is different from the isolated situation. This is related to the "direct" interaction of defects accompanying the key particle with the edge of the dimple. We propose that this nematic-amplified key-lock interaction can play an important role in self-organization and clustering of mixtures of colloidal particles with dimple colloids present.

  17. [Effects of recruitment maneuver in prone position on hemodynamics in patients with severe pulmonary infection].

    Science.gov (United States)

    Fan, Yuan-hua; Liu, Yuan-fei; Zhu, Hua-yong; Zhang, Min

    2012-02-01

    To evaluate effects of recruitment maneuver in prone position on hemodynamics in patients with severe pulmonary infection, based on the protective pulmonary ventilation strategy. Ninety-seven cases with severe pulmonary infection admitted to intensive care unit (ICU) of Ganzhou City People's Hospital undergoing mechanical ventilation were involved. Volume controlled ventilation mode with small tidal volume (8 ml/kg) and positive end-expiratory pressure (PEEP) of 6 cm H(2)O [1 cm H(2)O = 0.098 kPa] was conducted. Each patient underwent recruitment maneuver in supine position and then in prone position [PEEP 20 cm H(2)O+pressure control (PC) 20 cm H(2)O]. Heart rate (HR), mean arterial pressure (MAP), pulse oxygen saturation [SpO(2)] and blood gas analysis data were recorded before and after recruitment maneuver in either position. A double-lumen venous catheter was inserted into internal jugular vein or subclavian vein, and a pulse index contour cardiac output (PiCCO) catheter was introduced into femoral artery. Cardiac index (CI), stroke volume index (SVI), systemic vascular resistance index (SVRI), intra-thoracic blood volume index (ITBVI), extra vascular lung water index (EVLWI), global end-diastolic volume index (GEDVI), global ejection fraction (GEF), stroke volume variation (SVV) and central vein pressure (CVP) were monitored. (1) Compared with data before recruitment maneuver, there were no significant differences in HR and MAP after supine position and prone position recruitment maneuver, but significant differences in SpO(2) were found between before and after recruitment maneuver when patients' position was changed (supine position: 0.954 ± 0.032 vs. 0.917 ± 0.025, P recruitment maneuver (P recruitment maneuver, CI [L×min(-1)×m(-2)], SVI (ml/m(2)), GEDVI (ml/m(2)) and GEF were decreased significantly during recruitment maneuver (supine position: CI 3.2 ± 0.4 vs. 3.8 ± 0.6, SVI 32.4 ± 5.6 vs. 38.8 ± 6.5, GEDVI 689 ± 44 vs. 766 ± 32, GEF 0.267 ± 0

  18. Brain communication in the locked-in state.

    Science.gov (United States)

    De Massari, Daniele; Ruf, Carolin A; Furdea, Adrian; Matuz, Tamara; van der Heiden, Linda; Halder, Sebastian; Silvoni, Stefano; Birbaumer, Niels

    2013-06-01

    Patients in the completely locked-in state have no means of communication and they represent the target population for brain-computer interface research in the last 15 years. Although different paradigms have been tested and different physiological signals used, to date no sufficiently documented completely locked-in state patient was able to control a brain-computer interface over an extended time period. We introduce Pavlovian semantic conditioning to enable basic communication in completely locked-in state. This novel paradigm is based on semantic conditioning for online classification of neuroelectric or any other physiological signals to discriminate between covert (cognitive) 'yes' and 'no' responses. The paradigm comprised the presentation of affirmative and negative statements used as conditioned stimuli, while the unconditioned stimulus consisted of electrical stimulation of the skin paired with affirmative statements. Three patients with advanced amyotrophic lateral sclerosis participated over an extended time period, one of which was in a completely locked-in state, the other two in the locked-in state. The patients' level of vigilance was assessed through auditory oddball procedures to study the correlation between vigilance level and the classifier's performance. The average online classification accuracies of slow cortical components of electroencephalographic signals were around chance level for all the patients. The use of a non-linear classifier in the offline classification procedure resulted in a substantial improvement of the accuracy in one locked-in state patient achieving 70% correct classification. A reliable level of performance in the completely locked-in state patient was not achieved uniformly throughout the 37 sessions despite intact cognitive processing capacity, but in some sessions communication accuracies up to 70% were achieved. Paradigm modifications are proposed. Rapid drop of vigilance was detected suggesting attentional

  19. Injection locking of optomechanical oscillators via acoustic waves.

    Science.gov (United States)

    Huang, Ke; Hossein-Zadeh, Mani

    2018-04-02

    Injection locking is an effective technique for synchronization of oscillator networks and controlling the phase and frequency of individual oscillators. As such, exploring new mechanisms for injection locking of emerging oscillators is important for their usage in various systems. Here, we present the first demonstration of injection locking of a radiation pressure driven optomechanical oscillator (OMO) via acoustic waves. As opposed to previously reported techniques (based on pump modulation or direct application of a modulated electrostatic force), injection locking of OMO via acoustic waves does not require optical power modulation or physical contact with the OMO and it can be easily implemented on various platforms to lock different types of OMOs independent of their size and structure. Using this approach we have locked the phase and frequency of two distinct modes of a microtoroidal silica OMO to a piezoelectric transducer (PZT). We have characterized the behavior of the injection locked OMO with three acoustic excitation configurations and showed that even without proper acoustic impedance, matching the OMO can be locked to the PZT and tuned over 17 kHz with only -30 dBm of RF power fed to the PZT. The high efficiency, simplicity, and scalability of the proposed approach paves the road toward a new class of photonic systems that rely on synchronization of several OMOs to a single or multiple RF oscillators with applications in optical communication, metrology, and sensing. Beyond its practical applications, injection locking via acoustic waves can be used in fundamental studies in quantum optomechanics where thermal and optical isolation of the OMO are critical.

  20. Mechanical Constraints on Flight at High Elevation Decrease Maneuvering Performance of Hummingbirds.

    Science.gov (United States)

    Segre, Paolo S; Dakin, Roslyn; Read, Tyson J G; Straw, Andrew D; Altshuler, Douglas L

    2016-12-19

    High-elevation habitats offer ecological advantages including reduced competition, predation, and parasitism [1]. However, flying organisms at high elevation also face physiological challenges due to lower air density and oxygen availability [2]. These constraints are expected to affect the flight maneuvers that are required to compete with rivals, capture prey, and evade threats [3-5]. To test how individual maneuvering performance is affected by elevation, we measured the free-flight maneuvers of male Anna's hummingbirds in a large chamber translocated to a high-elevation site and then measured their performance at low elevation. We used a multi-camera tracking system to identify thousands of maneuvers based on body position and orientation [6]. At high elevation, the birds' translational velocities, accelerations, and rotational velocities were reduced, and they used less demanding turns. To determine how mechanical and metabolic constraints independently affect performance, we performed a second experiment to evaluate flight maneuvers in an airtight chamber infused with either normoxic heliox, to lower air density, or nitrogen, to lower oxygen availability. The hypodense treatment caused the birds to reduce their accelerations and rotational velocities, whereas the hypoxic treatment had no significant effect on maneuvering performance. Collectively, these experiments reveal how aerial maneuvering performance changes with elevation, demonstrating that as birds move up in elevation, air density constrains their maneuverability prior to any influence of oxygen availability. Our results support the hypothesis that changes in competitive ability at high elevations are the result of mechanical limits to flight performance [7]. Copyright © 2016 Elsevier Ltd. All rights reserved.

  1. DLS 5.0--the biomechanical effects of dynamic locking screws.

    Directory of Open Access Journals (Sweden)

    Stefan Döbele

    Full Text Available INTRODUCTION: Indirect reduction of dia-/metaphyseal fractures with minimally invasive implant application bridges the fracture zone in order to protect the soft-tissue and blood supply. The goal of this fixation strategy is to allow stable motion at the fracture site to achieve indirect bone healing with callus formation. However, concerns have arisen that the high axial stiffness and eccentric position of locked plating constructs may suppress interfragmentary motion and callus formation, particularly under the plate. The reason for this is an asymmetric fracture movement. The biological need for sufficient callus formation and secondary bone healing is three-dimensional micro movement in the fracture zone. The DLS was designed to allow for increased fracture site motion. The purpose of the current study was to determine the biomechanical effect of the DLS_5.0. METHODS: Twelve surrogate bone models were used for analyzing the characteristics of the DLS_5.0. The axial stiffness and the interfragmentary motion of locked plating constructs with DLS were compared to conventional constructs with Locking Head Screws (LS_5.0. A quasi-static axial load of 0 to 2.5 kN was applied. Relative motion was measured. RESULTS: The dynamic system showed a biphasic axial stiffness distribution and provided a significant reduction of the initial axial stiffness of 74.4%. Additionally, the interfragmentary motion at the near cortex increased significantly from 0.033 mm to 0.210 mm (at 200N. CONCLUSIONS: The DLS may ultimately be an improvement over the angular stable plate osteosynthesis. The advantages of the angular stability are not only preserved but even supplemented by a dynamic element which leads to homogenous fracture movement and to a potentially uniform callus distribution.

  2. Head, Neck, and Oral Cancer

    Medline Plus

    Full Text Available ... Head and Neck Pathology Oral, Head and Neck Pathology Close to 49,750 Americans will be diagnosed ... Head and Neck Pathology Oral, Head and Neck Pathology Close to 49,750 Americans will be diagnosed ...

  3. A scalable lock-free hash table with open addressing

    DEFF Research Database (Denmark)

    Nielsen, Jesper Puge; Karlsson, Sven

    2016-01-01

    and concurrent operations without any locks. In this paper, we present a new fully lock-free open addressed hash table with a simpler design than prior published work. We split hash table insertions into two atomic phases: first inserting a value ignoring other concurrent operations, then in the second phase......Concurrent data structures synchronized with locks do not scale well with the number of threads. As more scalable alternatives, concurrent data structures and algorithms based on widely available, however advanced, atomic operations have been proposed. These data structures allow for correct...

  4. Control of photon storage time using phase locking.

    Science.gov (United States)

    Ham, Byoung S

    2010-01-18

    A photon echo storage-time extension protocol is presented by using a phase locking method in a three-level backward propagation scheme, where phase locking serves as a conditional stopper of the rephasing process in conventional two-pulse photon echoes. The backward propagation scheme solves the critical problems of extremely low retrieval efficiency and pi rephasing pulse-caused spontaneous emission noise in photon echo based quantum memories. The physics of the storage time extension lies in the imminent population transfer from the excited state to an auxiliary spin state by a phase locking control pulse. We numerically demonstrate that the storage time is lengthened by spin dephasing time.

  5. Testing ultrafast mode-locking at microhertz relative optical linewidth.

    Science.gov (United States)

    Martin, Michael J; Foreman, Seth M; Schibli, T R; Ye, Jun

    2009-01-19

    We report new limits on the phase coherence of the ultrafast mode-locking process in an octave-spanning Ti:sapphire comb.We find that the mode-locking mechanism correlates optical phase across a full optical octave with less than 2.5 microHZ relative linewidth. This result is at least two orders of magnitude below recent predictions for quantum-limited individual comb-mode linewidths, verifying that the mode-locking mechanism strongly correlates quantum noise across the comb spectrum.

  6. Temperature-insensitive laser frequency locking near absorption lines

    International Nuclear Information System (INIS)

    Kostinski, Natalie; Olsen, Ben A.; Marsland, Robert III; McGuyer, Bart H.; Happer, William

    2011-01-01

    Combined magnetically induced circular dichroism and Faraday rotation of an atomic vapor are used to develop a variant of the dichroic atomic vapor laser lock that eliminates lock sensitivity to temperature fluctuations of the cell. Operating conditions that eliminate first-order sensitivity to temperature fluctuations can be determined by low-frequency temperature modulation. This temperature-insensitive gyrotropic laser lock can be accurately understood with a simple model, that is in excellent agreement with observations in potassium vapor at laser frequencies in a 2 GHz range about the 770.1 nm absorption line. The methods can be readily adapted for other absorption lines.

  7. Testing ultrafast mode-locking at microhertz relative optical linewidth

    OpenAIRE

    Martin, Michael J.; Foreman, Seth M.; Schibli, T. R.; Ye, Jun

    2008-01-01

    We report new limits on the phase coherence of the ultrafast mode-locking process in an octave-spanning Ti:sapphire comb. We find that the mode-locking mechanism correlates optical phase across a full optical octave with less than 2.5 micro Hz relative linewidth. This result is at least two orders of magnitude below recent predictions for quantum-limited individual comb-mode linewidths, verifying that the mode-locking mechanism strongly correlates quantum noise across the comb spectrum.

  8. Tilt-tuned etalon locking for tunable laser stabilization.

    Science.gov (United States)

    Gibson, Bradley M; McCall, Benjamin J

    2015-06-15

    Locking to a fringe of a tilt-tuned etalon provides a simple, inexpensive method for stabilizing tunable lasers. Here, we describe the use of such a system to stabilize an external-cavity quantum cascade laser; the locked laser has an Allan deviation of approximately 1 MHz over a one-second integration period, and has a single-scan tuning range of approximately 0.4  cm(-1). The system is robust, with minimal alignment requirements and automated lock acquisition, and can be easily adapted to different wavelength regions or more stringent stability requirements with minor alterations.

  9. Development of the Lock Protocol for DEPSKY Storage System

    Directory of Open Access Journals (Sweden)

    NASCIMENTO, P. S.

    2015-06-01

    Full Text Available Data management in environments based on several clouds (cloud-of-clouds should be dependable and secure. DEPSKY may assure that characteristics through mechanisms as cryptography and data replication, however DEPSKY does not support concurrent writing, a desirable functionality for many applications. This paper presents the development and a performance analysis of a lock algorithmfor DEPSKY storage system. The paper also presents validation test and performance test of the algorithm. Such protocol allows concurrent writing, through a low contention lock mechanism that uses lock filesfi to dene who is allowed to write in a data unit.

  10. Squeezing in an injection-locked semiconductor laser

    Science.gov (United States)

    Inoue, S.; Machida, S.; Yamamoto, Y.; Ohzu, H.

    1993-09-01

    The intensity-noise properties of an injection-locked semiconductor laser were studied experimentally. The constant-current-driven semiconductor laser producing the amplitude-squeezed state whose intensity noise was reduced below the standard quantum limit (SQL) by 0.72 dB was injection-locked by an external master laser. The measured intensity-noise level of the injection-locked semiconductor laser was 0.91 dB below the SQL. This experimental result indicates that a phase-coherent amplitude-squeezed state or squeezed vacuum state together with a reference local oscillator wave can be generated directly by semiconductor laser systems.

  11. Ship operation and failure mode analysis using a maneuver simulator

    Science.gov (United States)

    Cabrerizo-Morales, Miguel Angel; Molina, Rafael; de los Santos, Francisco; Camarero, Alberto

    2013-04-01

    In a ship or floating structure operation the agents that contribute to the systems behaviour are not only those derived from fluid-structure interaction, but also the ones linked to mooring-control line set-up evolution and human interaction. Therefore, the analysis of such systems is affected by boundary conditions that change during a complete operation. Frequently, monitoring techniques in laboratory (model) and field (prototype) are based in different instrumental techniques adding difficulty to data comparison and, in some cases, inducing precision and repeatability errors. For this reason, the main aim of this study is to develop the methods and tools to achieve a deep knowledge of those floating systems and obtain capabilities to optimize their operationally thresholds. This abstract presents a methodology and an instrumental system applicable both in field and laboratory: SRECMOCOS Project (Small scale REal-time Caisson MOnitoring and COntrol System). SRECMOCOS compiles three modules. For the monitoring and control of the structure it has been developed a synchronized open and modular microcontroller-based electronic system that comprises sensors, to monitor agents and reactions, and actuators to perform pertinent actions after processing the sensors' data. A secondary objective has been to design and implement a global scaled simulator (1:22), at the 3D basin of The Harbour Research Lab at Technical University of Madrid, in which climatic agents and those derived from the rig/maneuvering setup and the structural design were included. The particular case of Campamento's drydock, in Algeciras Bay (Spain), has been used to apply and validate the methodology. SRECMOCOS Project conjugates control, monitoring and wireless communication systems in a real time basis, offering the possibility to register and simulate all the parameters involved in port operations. This approach offers a step forward into a monitoring strategy to be included in monitoring

  12. Effects of Self-Instructional Methods and Above Real Time Training (ARTT) for Maneuvering Tasks on a Flight Simulator

    Science.gov (United States)

    Ali, Syed Firasat; Khan, Javed Khan; Rossi, Marcia J.; Crane, Peter; Heath, Bruce E.; Knighten, Tremaine; Culpepper, Christi

    2003-01-01

    Personal computer based flight simulators are expanding opportunities for providing low-cost pilot training. One advantage of these devices is the opportunity to incorporate instructional features into training scenarios that might not be cost effective with earlier systems. Research was conducted to evaluate the utility of different instructional features using a coordinated level turn as an aircraft maneuvering task. In study I, a comparison was made between automated computer grades of performance with certified flight instructors grades. Every one of the six student volunteers conducted a flight with level turns at two different bank angles. The automated computer grades were based on prescribed tolerances on bank angle, airspeed and altitude. Two certified flight instructors independently examined the video tapes of heads up and instrument displays of the flights and graded them. The comparison of automated grades with the instructors grades was based on correlations between them. In study II, a 2x2 between subjects factorial design was used to devise and conduct an experiment. Comparison was made between real time training and above real time training and between feedback and no feedback in training. The performance measure to monitor progress in training was based on deviations in bank angle and altitude. The performance measure was developed after completion of the experiment including the training and test flights. It was not envisaged before the experiment. The experiment did not include self- instructions as it was originally planned, although feedback by experimenter to the trainee was included in the study.

  13. Kristeller maneuvers or fundal pressure and maternal/neonatal morbidity: obstetric and judicial literature review.

    Science.gov (United States)

    Malvasi, Antonio; Zaami, Simona; Tinelli, Andrea; Trojano, Giuseppe; Montanari Vergallo, Gianluca; Marinelli, Enrico

    2018-02-21

    A significant amount of data concerning maternal-fetal damage arising from the exertion of Kristeller maneuvers (KMs) or fundal pressure (FP) go unreleased due to medicolegal implications. For this reason, the paper gathers information as to the real magnitude of litigation related to FP-induced damages and injuries. The authors have undertaken a research in order to include general search engines (PubMed-Medline, Cochrane, Embase, Google, GyneWeb) and legal databases (De Jure, Italian database of jurisprudence daily update; Westlaw, Thomson Reuters, American ruling database and Bailii, UK Court Ruling Database). Results confirm said phenomenon to be more wide ranging than it appears through official channels. Several courts of law, both in the United States of America (USA) and in European Union (EU) Member States as well, have ruled against the use of the maneuver itself, assuming a stance conducive to a presumption of guilt against those doctors and healthcare providers who resorted to KMs or FP during deliveries. Given how rife FP is in mainstream obstetric practice, it is as if there were a wide gap between obstetric real-life and what official jurisprudence and healthcare institutions-sanctioned official practices are. The authors think that it would be desirable to draft specifically targeted guidelines or recommendations on maneuvers during vaginal delivery, in which to point out exactly what kinds of maneuvering techniques are to be absolutely banned and what maneuvers are to be allowed, and under what conditions their application can be considered appropriate.

  14. Adaptive ISAR Imaging of Maneuvering Targets Based on a Modified Fourier Transform.

    Science.gov (United States)

    Wang, Binbin; Xu, Shiyou; Wu, Wenzhen; Hu, Pengjiang; Chen, Zengping

    2018-04-27

    Focusing on the inverse synthetic aperture radar (ISAR) imaging of maneuvering targets, this paper presents a new imaging method which works well when the target's maneuvering is not too severe. After translational motion compensation, we describe the equivalent rotation of maneuvering targets by two variables-the relative chirp rate of the linear frequency modulated (LFM) signal and the Doppler focus shift. The first variable indicates the target's motion status, and the second one represents the possible residual error of the translational motion compensation. With them, a modified Fourier transform matrix is constructed and then used for cross-range compression. Consequently, the imaging of maneuvering is converted into a two-dimensional parameter optimization problem in which a stable and clear ISAR image is guaranteed. A gradient descent optimization scheme is employed to obtain the accurate relative chirp rate and Doppler focus shift. Moreover, we designed an efficient and robust initialization process for the gradient descent method, thus, the well-focused ISAR images of maneuvering targets can be achieved adaptively. Human intervention is not needed, and it is quite convenient for practical ISAR imaging systems. Compared to precedent imaging methods, the new method achieves better imaging quality under reasonable computational cost. Simulation results are provided to validate the effectiveness and advantages of the proposed method.

  15. Multiple Maneuvering Target Tracking by Improved Particle Filter Based on Multiscan JPDA

    Directory of Open Access Journals (Sweden)

    Jing Liu

    2012-01-01

    Full Text Available The multiple maneuvering target tracking algorithm based on a particle filter is addressed. The equivalent-noise approach is adopted, which uses a simple dynamic model consisting of target state and equivalent noise which accounts for the combined effects of the process noise and maneuvers. The equivalent-noise approach converts the problem of maneuvering target tracking to that of state estimation in the presence of nonstationary process noise with unknown statistics. A novel method for identifying the nonstationary process noise is proposed in the particle filter framework. Furthermore, a particle filter based multiscan Joint Probability Data Association (JPDA filter is proposed to deal with the data association problem in a multiple maneuvering target tracking. In the proposed multiscan JPDA algorithm, the distributions of interest are the marginal filtering distributions for each of the targets, and these distributions are approximated with particles. The multiscan JPDA algorithm examines the joint association events in a multiscan sliding window and calculates the marginal posterior probability based on the multiscan joint association events. The proposed algorithm is illustrated via an example involving the tracking of two highly maneuvering, at times closely spaced and crossed, targets, based on resolved measurements.

  16. oVEMP as an objective indicator of successful repositioning maneuver.

    Science.gov (United States)

    Asal, Samir; Sobhy, Osama; Balbaa, Amany

    Benign paroxysmal positioning vertigo (BPPV) is the most common peripheral vestibular disorder. Canalolithiasis in the posterior semi-circular canal is the most common underlying pathology that can be treated effectively by repositioning maneuvers. Our hypothesis suggested that successful maneuvers can lead to repositioning of dislodged otoconia to the utricle. Air conducted oVEMP, which is thought to originate from the contra-lateral utricular organ was measured in twenty patients with unilateral BPPV and we compared n1-p1 peak to peak amplitude of the affected ears in 3 separate intervals: on pre-treatment when typical nystagmus was confirmed, immediately after, and 1 week after repositioning maneuvers to assess change, if any, in amplitude. This study showed significant increase of oVEMP amplitude in the affected ears after successful repositioning maneuver that was more significant after 1 week. oVEMP can be used as a reliable objective test for ensuring a successful maneuver rather than subjective dependence on the patient's symptoms, which may be misleading due to a remission. Copyright © 2017 Elsevier España, S.L.U. and Sociedad Española de Otorrinolaringología y Cirugía de Cabeza y Cuello. All rights reserved.

  17. A Comparison of Obstetric Maneuvers for the Acute Management of Shoulder Dystocia

    Science.gov (United States)

    Hoffman, Matthew K; Bailit, Jennifer L; Branch, D. Ware; Burkman, Ronald T; Van Veldhusien, Paul; Lu, Li; Kominiarek, Michelle A.; Hibbard, Judith U; Landy, Helain J; Haberman, Shoshana; Wilkins, Isabelle; Gonzalez Quintero, Victor H; Gregory, Kimberly D; Hatjis, Christos G; Ramirez, Mildred M; Reddy, Uma M.; Troendle, James; Zhang, Jun

    2011-01-01

    Objective To assess the efficacy of obstetric maneuvers for resolving shoulder dystocia, and the effect that these maneuvers have on neonatal injury when shoulder dystocia occurs. Methods Using an electronic database encompassing 206,969 deliveries, we identified all women with a vertex fetus beyond 34 0/7 weeks of gestation who incurred a shoulder dystocia during the process of delivery. Women whose fetuses had a congenital anomaly and women with an antepartum stillbirth were excluded. Medical records of all cases were reviewed by trained abstractors. Cases involving neonatal injury (defined as brachial plexus injury, clavicular or humerus fracture, or hypoxic ischemic encephalopathy or intrapartum neonatal death attributed to the shoulder dystocia) were compared to those without injury. RESULTS Among 132,098 women who delivered a term cephalic liveborn fetus vaginally, 2,018 incurred a shoulder dystocia (1.5%), and 101 (5.2%) of these incurred a neonatal injury. Delivery of the posterior shoulder was associated with the highest rate of delivery when compared to other maneuvers (84.4% compared with 24.3% to 72.0% for other maneuvers; Pdystocia. The need for additional maneuvers was associated with higher rates of neonatal injury. PMID:21555962

  18. ''Old'' locked inflation

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Yang; Piao, Yun-Song [College of Physical Sciences, Graduate University of Chinese Academy of Sciences, Beijing 100049 (China); Si, Zong-Guo, E-mail: liuyangbyf@mail.sdu.edu.cn, E-mail: yspiao@gucas.ac.cn, E-mail: zgsi@sdu.edu.cn [Department of Physics, Shandong University, Jinan 250100 (China)

    2009-05-15

    In this paper, we revisit the idea of locked inflation, which does not require a potential satisfying the normal slow-roll condition, but suffers from the problems associated with ''saddle inflation''. We propose a scenario based on locked inflation, however, with an alternative evolution mechanism of the ''waterfall field'' {phi}. Instead of rolling down along the potential, the {phi} field will tunnel to end the inflation stage like in old inflation, by which the saddle inflation could be avoided. Further, we study a cascade of old locked inflation, which can be motivated by the string landscape. Our model is based on the consideration of making locked inflation feasible so as to give a working model without slow roll; It also can be seen as an effort to embed the old inflation in string landscape.

  19. Towards automatic proofs of lock-free algorithms

    OpenAIRE

    Fejoz , Loïc; Merz , Stephan

    2008-01-01

    International audience; The verification of lock-free data structures has traditionally been considered as difficult. We propose a formal model for describing such algorithms. The verification conditions generated from this model can often be handled by automatic theorem provers.

  20. Experimental study on working characteristics of density lock

    International Nuclear Information System (INIS)

    Sun Furong; Yan Changqi; Gu Haifeng

    2011-01-01

    The working principle of density lock was introduced in this paper, and the experimental loop was built so that researches on working performance of density lock in the system were done at steady-state operation and pump trip conditions. The results show that at steady-state operation conditions, density lock can keep close in a long run, which will separate passive residual heat removal circuit from primary circuit. As a result, passive residual heat removal circuit is in the non-operating conditions, which dose not influence normal operation of reactors. At the pump trip conditions, density lock can be automatically opened quickly, which will make primary and passive residual heat removal system communicated. The natural circulation is well established in the two systems, and is enough to ensure removal of residual heat. (authors)

  1. Active stabilization of a diode laser injection lock

    Energy Technology Data Exchange (ETDEWEB)

    Saxberg, Brendan; Plotkin-Swing, Benjamin; Gupta, Subhadeep [Department of Physics, University of Washington, P.O. Box 351560, Seattle, Washington 98195-1560 (United States)

    2016-06-15

    We report on a device to electronically stabilize the optical injection lock of a semiconductor diode laser. Our technique uses as discriminator the peak height of the laser’s transmission signal on a scanning Fabry-Perot cavity and feeds back to the diode current, thereby maintaining maximum optical power in the injected mode. A two-component feedback algorithm provides constant optimization of the injection lock, keeping it robust to slow thermal drifts and allowing fast recovery from sudden failures such as temporary occlusion of the injection beam. We demonstrate the successful performance of our stabilization method in a diode laser setup at 399 nm used for laser cooling of Yb atoms. The device eases the requirements on passive stabilization and can benefit any diode laser injection lock application, particularly those where several such locks are employed.

  2. Active stabilization of a diode laser injection lock.

    Science.gov (United States)

    Saxberg, Brendan; Plotkin-Swing, Benjamin; Gupta, Subhadeep

    2016-06-01

    We report on a device to electronically stabilize the optical injection lock of a semiconductor diode laser. Our technique uses as discriminator the peak height of the laser's transmission signal on a scanning Fabry-Perot cavity and feeds back to the diode current, thereby maintaining maximum optical power in the injected mode. A two-component feedback algorithm provides constant optimization of the injection lock, keeping it robust to slow thermal drifts and allowing fast recovery from sudden failures such as temporary occlusion of the injection beam. We demonstrate the successful performance of our stabilization method in a diode laser setup at 399 nm used for laser cooling of Yb atoms. The device eases the requirements on passive stabilization and can benefit any diode laser injection lock application, particularly those where several such locks are employed.

  3. Development of thermal actuators with multi-locking positions

    Science.gov (United States)

    Luo, J. K.; Zhu, Y.; Fu, Y. Q.; Flewitt, A. J.; Spearing, S. M.; Miao, J. M.; Milne, W. I.

    2006-04-01

    To reduce power consumption and operation temperature for micro-thermal actuators, metal-based micro-mechanical locks with multi-locking positions were analyzed and fabricated. The micro-locks consist of two or three U-shaped thermal actuators. The devices were made by a single mask process using electroplated Ni as the active material. Tests showed that the metal based thermal actuators deliver a maximum displacement of ~20µm at a much lower temperature than that of Si-based actuators. However Ni-actuators showed a severe back bending, which increases with increasing applied power. The temperature to initiate the back bending is as low as ~240°C. Back bending increases the distance between the two actuators, and leads to locking function failure. For practical application, Ni-based thermal actuators must be operated below 200°C.

  4. Microbiocidal effects of various taurolidine containing catheter lock solutions

    NARCIS (Netherlands)

    Olthof, E.D.; Nijland, R van; Gulich, A.F.; Wanten, G.J.A.

    2015-01-01

    BACKGROUND & AIMS: We have recently shown that a catheter lock solution containing taurolidine dramatically decreases catheter-related bloodstream infections (CRBSI) in patients on home parenteral nutrition (HPN) when compared to heparin. Since several taurolidine formulations are commercially

  5. Clinical Outcomes after Open Locked Intramedullary Nailing of ...

    African Journals Online (AJOL)

    2018-02-07

    Feb 7, 2018 ... above who presented within 2 weeks of sustaining closed femoral shaft fractures ... tweak, and build upon the work non-commercially, as long as the author is ... was compressed, and proximal locking screws were then.

  6. Self-mode-locked Nd3+:YAG laser

    International Nuclear Information System (INIS)

    Komarov, A K; Komarov, K P; Kuch'yanov, Aleksandr S

    2003-01-01

    Self-mode-locking was observed in a Nd 3+ :YAG laser with a negative feedback without introducing any nonlinear elements into the laser cavity. The laser generates during pumping 300 - 500-ps single pulses on an axial period. (lasers)

  7. Mode-Locked Semiconductor Lasers for Optical Communication Systems

    DEFF Research Database (Denmark)

    Yvind, Kresten; Larsson, David; Oxenløwe, Leif Katsuo

    2005-01-01

    We present investigations on 10 and 40 GHz monolithic mode-locked lasers for applications in optical communications systems. New all-active lasers with one to three quantum wells have been designed, fabricated and characterized....

  8. Development of Phase Lock Loop System for Synchronisation of a ...

    African Journals Online (AJOL)

    Akorede

    KEYWORDS: Phase locked loop (PLL), grid synchronisation, simulations, PI regulator, hybrid system. .... system. AC. - D. C co nv erter. DC-DC converter. DC. - AC co nverter. Load ... The box named Discrete Transfer Fcn is the PI-regulator.

  9. Actuator assembly including a single axis of rotation locking member

    Science.gov (United States)

    Quitmeyer, James N.; Benson, Dwayne M.; Geck, Kellan P.

    2009-12-08

    An actuator assembly including an actuator housing assembly and a single axis of rotation locking member fixedly attached to a portion of the actuator housing assembly and an external mounting structure. The single axis of rotation locking member restricting rotational movement of the actuator housing assembly about at least one axis. The single axis of rotation locking member is coupled at a first end to the actuator housing assembly about a Y axis and at a 90.degree. angle to an X and Z axis providing rotation of the actuator housing assembly about the Y axis. The single axis of rotation locking member is coupled at a second end to a mounting structure, and more particularly a mounting pin, about an X axis and at a 90.degree. angle to a Y and Z axis providing rotation of the actuator housing assembly about the X axis. The actuator assembly is thereby restricted from rotation about the Z axis.

  10. Firearm Safety Locks: Federal Agency Implementation of the Presidential Directive

    National Research Council Canada - National Science Library

    1998-01-01

    ... deaths among children ages 5 to 14. In order to have the federal government serve as an example of gun safety, the President required that a safety lock device be provided with each handgun issued to federal law enforcement officers...

  11. Active stabilization of a diode laser injection lock

    International Nuclear Information System (INIS)

    Saxberg, Brendan; Plotkin-Swing, Benjamin; Gupta, Subhadeep

    2016-01-01

    We report on a device to electronically stabilize the optical injection lock of a semiconductor diode laser. Our technique uses as discriminator the peak height of the laser’s transmission signal on a scanning Fabry-Perot cavity and feeds back to the diode current, thereby maintaining maximum optical power in the injected mode. A two-component feedback algorithm provides constant optimization of the injection lock, keeping it robust to slow thermal drifts and allowing fast recovery from sudden failures such as temporary occlusion of the injection beam. We demonstrate the successful performance of our stabilization method in a diode laser setup at 399 nm used for laser cooling of Yb atoms. The device eases the requirements on passive stabilization and can benefit any diode laser injection lock application, particularly those where several such locks are employed.

  12. Design and Performance Test of Locking Curved-Nut

    Energy Technology Data Exchange (ETDEWEB)

    Cha, Min Cheol; Kang, Ho Sung; Kim, Do Yeop; Lee, Suk Yong; Lee, Eung Suk [Chungbuk Nat’l Univ., Cheongju (Korea, Republic of); Jeong, Hui Jong [Viblock Company, Cheongwon (Korea, Republic of)

    2017-03-15

    Many types of locking nut are commercializing in the various industries where has heavy vibration. Because Nut's loosing causes a serious accident. But the most locking nuts are too expensive as the complicate manufacturing process. In this study, we design the new type of locking nut, 'Curved-Nut' that is relatively simple making process. We study a relation between the elastic energy and the nut loosing mechanism. So it is analysed, the elastic energy of Curved-Nut comparing with the locking test. The Curved-Nut was manufactured on the commercial nut using a milling tool with horizontal cutting, one or two time under the nut. As the result, the more elastic energy the more prevent the loosing of the nut. We verified the performance of the loosing nut using the vibration testing equipment (NAS3350).

  13. Vortex locking in direct numerical simulations of quantum turbulence.

    Science.gov (United States)

    Morris, Karla; Koplik, Joel; Rouson, Damian W I

    2008-07-04

    Direct numerical simulations are used to examine the locking of quantized superfluid vortices and normal fluid vorticity in evolving turbulent flows. The superfluid is driven by the normal fluid, which undergoes either a decaying Taylor-Green flow or a linearly forced homogeneous isotropic turbulent flow, although the back reaction of the superfluid on the normal fluid flow is omitted. Using correlation functions and wavelet transforms, we present numerical and visual evidence for vortex locking on length scales above the intervortex spacing.

  14. Enforced Electrical Neutrality of the Color-Flavor Locked Phase

    International Nuclear Information System (INIS)

    Rajagopal, Krishna; Wilczek, Frank

    2001-01-01

    We demonstrate that quark matter in the color-flavor locked phase of QCD is rigorously electrically neutral, despite the unequal quark masses, and even in the presence of an electron chemical potential. As long as the strange quark mass and the electron chemical potential do not preclude the color-flavor locked phase, quark matter is automatically neutral. No electrons are required and none are admitted

  15. Active Stabilization of a Diode Laser Injection Lock

    OpenAIRE

    Saxberg, Brendan; Plotkin-Swing, Benjamin; Gupta, Subhadeep

    2016-01-01

    We report on a device to electronically stabilize the optical injection lock of a semiconductor diode laser. Our technique uses as discriminator the peak height of the laser's transmission signal on a scanning Fabry-Perot cavity and feeds back to the diode current, thereby maintaining maximum optical power in the injected mode. A two-component feedback algorithm provides constant optimization of the injection lock, keeping it robust to slow thermal drifts and allowing fast recovery from sudde...

  16. Technique for Determining Lock Coefficient of Differential "Quif"

    Directory of Open Access Journals (Sweden)

    A. B. Fominyh

    2015-01-01

    Full Text Available Increasing the traction qualities of cars on the black ice and snow-covered roads is a relevant task. There are two ways to solve this task, i.e. optimize distribution of the power stream between the driving wheels of the car; introduce a differential (differentials of the increased friction in transmission.Now, an installation of the increased friction differential in transmission is the most widespread measure to increase traction properties of cars. The differential of design "Quif" is one of such differentials. To estimate the efficiency degree of using such a differential is possible either experimentally or theoretically. In case of theoretically determined usefulness of this differential design, as an estimate indicator of the differential installation in transmission a coefficient of lock is accepted.The article considers an algorithm and a technique to calculate a lock coefficient of the differential design "Quif" allowing us to define numeric values of the lock coefficient of such differential at designing stage. It also considers how the lock coefficient depends on the gearing angle and tilt angle of the gear wheel teeth of differential. The given estimating algorithm of designated parameter of differential has more logical and compact structure with regard to the known ones. The lock coefficient values calculated by the offered technique differ from the experimental data by no more than 12%. Taking into account abovementioned, the presented technique for calculating lock coefficient of differential "Quif" is advisable for practical application.

  17. Pressure locking and thermal binding of gate valves

    Energy Technology Data Exchange (ETDEWEB)

    Kelly, E.M.

    1996-12-01

    Pressure locking and thermal binding represent potential common mode failure mechanisms that can cause safety-related power-operated gate valves to fail in the closed position, thus rendering redundant safety-related systems incapable of performing their safety functions. Supplement 6 to Generic Letter 89-10, {open_quotes}Safety-Related Motor-Operated Gate Valve Testing and Surveillance,{close_quotes} provided an acceptable approach to addressing pressure locking and thermal binding of gate valves. More recently, the NRC has issued Generic Letter 95-07, {open_quotes}Pressure Locking and Thermal Binding of Safety-Related Power-Operated Gate Valves,{close_quotes} to request that licensees take certain actions to ensure that safety-related power-operated gate valves that are susceptible to pressure locking or thermal binding are capable of performing their safety functions within the current licensing bases. Over the past two years, several plants in Region I determined that valves in certain systems were potentially susceptible to pressure locking and thermal binding, and have taken various corrective actions. The NRC Region I Systems Engineering Branch has been actively involved in the inspection of licensee actions in response to the pressure locking and thermal binding issue. Region I continues to maintain an active involvement in this area, including participation with the Office of Nuclear Reactor Regulation in reviewing licensee responses to Generic Letter 95-07.

  18. Experimental implementation of phase locking in a nonlinear interferometer

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Hailong; Jing, Jietai, E-mail: jtjing@phy.ecnu.edu.cn [State Key Laboratory of Precision Spectroscopy, Department of Physics, East China Normal University, Shanghai 200062 (China); Marino, A. M. [Homer L. Dodge Department of Physics and Astronomy, The University of Oklahoma, 440 West Brooks Street, Norman, Oklahoma 73019 (United States)

    2015-09-21

    Based upon two cascade four-wave mixing processes in two identical hot rubidium vapor cells, a nonlinear interferometer has been experimentally realized [Jing et al., Appl. Phys. Lett. 99, 011110 (2011); Hudelist et al., Nat. Commun. 5, 3049 (2014)]. It has a higher degree of phase sensitivity than a traditional linear interferometer and has many potential applications in quantum metrology. Phase locking of the nonlinear interferometer is needed before it can find its way into applications. In this letter, we investigate the experimental implementation of phase locking of the relative phase between the three beams at different frequencies involved in such a nonlinear interferometer. We have utilized two different methods, namely, beat note locking and coherent modulation locking. We find that coherent modulation locking can achieve much better phase stability than beat note locking in our system. Our results pave the way for real applications of a nonlinear interferometer in precision measurement and quantum manipulation, for example, phase control in phase-sensitive N-wave mixing process, N-port nonlinear interferometer and quantum-enhanced real-time phase tracking.

  19. Locked doors in acute inpatient psychiatry: a literature review.

    Science.gov (United States)

    van der Merwe, M; Bowers, L; Jones, J; Simpson, A; Haglund, K

    2009-04-01

    Many acute inpatient psychiatric wards in the UK are permanently locked, although this is contrary to the current Mental Health Act Code of Practice. To conduct a literature review of empirical articles concerning locked doors in acute psychiatric inpatient wards, an extensive literature search was performed in SAGE Journals Online, EBM Reviews, British Nursing Index, CINAHL, EMBASE Psychiatry, International Bibliography of the Social Sciences, Ovid MEDLINE, PsycINFO and Google, using the search terms 'open$', 'close$', '$lock$', 'door', 'ward', 'hospital', 'psychiatr', 'mental health', 'inpatient' and 'asylum'. A total of 11 empirical papers were included in the review. Both staff and patients reported advantages (e.g. preventing illegal substances from entering the ward and preventing patients from absconding and harming themselves or others) and disadvantages (e.g. making patients feel depressed, confined and creating extra work for staff) regarding locked doors. Locked wards were associated with increased patient aggression, poorer satisfaction with treatment and more severe symptoms. The limited literature available showed the urgent need for research to determine the real effects of locked doors in inpatient psychiatry.

  20. Ground Track Acquisition and Maintenance Maneuver Modeling for Low-Earth Orbit Satellite

    Directory of Open Access Journals (Sweden)

    Byoung-Sun Lee

    1997-12-01

    Full Text Available This paper presents a comprehensive analytical approach for determining key maneuver parameters associated with the acquisition and maintenance of the ground track for a low-earth orbit. A livearized model relating changes in the drift rate of the ground track directly to changes in the orbital semi-major axis is also developed. The effect of terrestrial atmospheric drag on the semi-major axis is also explored, being quantified through an analytical expression for the decay rate as a function of density. The non-singular Lagrange planetary equations, further simplified for nearly circular orbits, provide the desired relationships between the corrective in-plane impulsive velocity increments and the corresponding effects on the orbit elements. The resulting solution strategy offers excellent insight into the dynamics affecting the timing, magnitude, and frequency of these maneuvers. Simulations are executed for the ground track acquisition and maintenance maneuver as a pre-flight planning and analysis.

  1. Associating crash avoidance maneuvers with driver attributes and accident characteristics: a mixed logit model approach

    DEFF Research Database (Denmark)

    Kaplan, Sigal; Prato, Carlo Giacomo

    2012-01-01

    from the key role of proactive and state-aware road users within the concept of sustainable safety systems, as well as from the key role of effective corrective maneuvers in the success of automated in-vehicle warning and driver assistance systems. Methods: The analysis is conducted by means of a mixed...... about the risks of driving under fatigue and distraction being comparable to the risks of driving under the influence of alcohol and drugs. Moreover, the results suggest the need to educate drivers about hazard perception, designing a forgiving infrastructure within a sustainable safety systems......Objective: The current study focuses on the propensity of drivers to engage in crash avoidance maneuvers in relation to driver attributes, critical events, crash characteristics, vehicles involved, road characteristics, and environmental conditions. The importance of avoidance maneuvers derives...

  2. Effect of Conflict Resolution Maneuver Execution Delay on Losses of Separation

    Science.gov (United States)

    Cone, Andrew C.

    2010-01-01

    This paper examines uncertainty in the maneuver execution delay for data linked conflict resolution maneuvers. This uncertainty could cause the previously cleared primary conflict to reoccur or a secondary conflict to appear. Results show that the likelihood of a primary conflict reoccurring during a horizontal conflict resolution maneuver increases with larger initial turn-out angles and with shorter times until loss of separation. There is also a significant increase in the probability of a primary conflict reoccurring when the time until loss falls under three minutes. Increasing horizontal separation by an additional 1.5 nmi lowers the risk, but does not completely eliminate it. Secondary conflicts were shown to have a small probability of occurring in all tested configurations.

  3. Contingency Trajectory Design for a Lunar Orbit Insertion Maneuver Failure by the LADEE Spacecraft

    Science.gov (United States)

    Genova, A. L.

    2014-01-01

    This paper presents results from a contingency trajectory analysis performed for the Lunar Atmosphere & Dust Environment Explorer (LADEE) mission in the event of a missed lunar-orbit insertion (LOI) maneuver by the LADEE spacecraft. The effects of varying solar perturbations in the vicinity of the weak stability boundary (WSB) in the Sun-Earth system on the trajectory design are analyzed and discussed. It is shown that geocentric recovery trajectory options existed for the LADEE spacecraft, depending on the spacecraft's recovery time to perform an Earth escape-prevention maneuver after the hypothetical LOI maneuver failure and subsequent path traveled through the Sun-Earth WSB. If Earth-escape occurred, a heliocentric recovery option existed, but with reduced science capacapability for the spacecraft in an eccentric, not circular near-equatorial retrograde lunar orbit.

  4. Maneuver Analysis and Targeting Strategy for the Stardust Re-Entry Capsule

    Science.gov (United States)

    Helfrich, Cliff; Bhat, Ramachand S.; Kangas, Julie A.; Wilson, Roby S.; Wong, Mau C.; Potts, Christopher L.; Williams, Kenneth E.

    2006-01-01

    The Stardust Sample Return Capsule (SRC) returned to Earth on January 15, 2006 after seven years of collecting interstellar and comet particles over three heliocentric revolutions, as shown in Figure 1. The SRC was carried on board the Stardust spacecraft, as shown in Figure 2. Because the spacecraft was built with unbalanced thrusters, turns and attitude control maintenance resulted in undesirable delta-v being imparted to the trajectory. As a result, a carefully planned maneuver strategy was devised to accurately target the Stardust capsule to the Utah Test and Training Range (UTTR). This paper provides an overview of the Stardust spacecraft and mission and describes the maneuver strategy that was employed to achieve the stringent targeting requirements for landing in Utah. In addition, an overview of Stardust maneuver analysis tools and techniques will also be presented.

  5. Tracking Maneuvering Group Target with Extension Predicted and Best Model Augmentation Method Adapted

    Directory of Open Access Journals (Sweden)

    Linhai Gan

    2017-01-01

    Full Text Available The random matrix (RM method is widely applied for group target tracking. The assumption that the group extension keeps invariant in conventional RM method is not yet valid, as the orientation of the group varies rapidly while it is maneuvering; thus, a new approach with group extension predicted is derived here. To match the group maneuvering, a best model augmentation (BMA method is introduced. The existing BMA method uses a fixed basic model set, which may lead to a poor performance when it could not ensure basic coverage of true motion modes. Here, a maneuvering group target tracking algorithm is proposed, where the group extension prediction and the BMA adaption are exploited. The performance of the proposed algorithm will be illustrated by simulation.

  6. Steelhead Spawning Surveys Near Locke Island, Hanford Reach of the Columbia River; TOPICAL

    International Nuclear Information System (INIS)

    DR Geist; RP Mueller

    1999-01-01

    In 1997, the National Marine Fisheries Service (NMFS) listed upper Columbia River steelhead trout (Oncorhynchus znykiss) as endangered. This action affected management of land-use activities along and within the Hanford Reach of the Columbia River, which flows through the U.S. Department of Energy (DOE) Hanford Site. Steelhead covered in this listing include all naturally spawned populations of steel-head and their progeny in streams in the Columbia River Basin upstream from the Yakima River to the United States/Canada border. The NMFS has identified a general listing of activities that could potentially result in harm to steelhead (62 FR 43937, August 18, 1997). One of these concerns includes land-use changes resulting in mass wasting or surface erosion. Landslide activity along the White Bluffs on the east ,side of Locke Island has redirected river flow into the island where substantial erosion has occurred. This erosion has exposed important anthropological and archaeological resources that were previously buried on the island. The DOE is working with affected tribes and other agencies to develop a plan for addressing the erosion of Locke Island. As part of this effort, the U.S. Army Corps of Engineers has prepared an assessment of potential alternatives to stabilize the erosion, including a no-action alternative. Steelhead historically spawned in the vicinity of Locke Island, but recent information on the occurrence of steelhead spawning or availability of spawning habitat was lacking. Therefore, the purpose of this study was to determine if steelhead spawned in the vicinity of Locke Island erosion and to evaluate the composition of substrate in the affected area. Surveys to document the occurrence of steelheads redds were conducted in Spring 1999. The surveys were conducted from the air as well as with the use of an underwater video camera. Neither aerial nor underwater surveys documented steelhead spawning within the survey area. Habitat surveys were

  7. Analysis of effects of manhole covers on motorcycle driver maneuvers: a nonparametric classification tree approach.

    Science.gov (United States)

    Chang, Li-Yen

    2014-01-01

    A manhole cover is a removable plate forming the lid over the opening of a manhole to allow traffic to pass over the manhole and to prevent people from falling in. Because most manhole covers are placed in roadway traffic lanes, if these manhole covers are not appropriately installed or maintained, they can represent unexpected hazards on the road, especially for motorcycle drivers. The objective of this study is to identify the effects of manhole cover characteristics as well as driver factors and traffic and roadway conditions on motorcycle driver maneuvers. A video camera was used to record motorcycle drivers' maneuvers when they encountered an inappropriately installed or maintained manhole cover. Information on 3059 drivers' maneuver decisions was recorded. Classification and regression tree (CART) models were applied to explore factors that can significantly affect motorcycle driver maneuvers when passing a manhole cover. Nearly 50 percent of the motorcycle drivers decelerated or changed their driving path to reduce the effects of the manhole cover. The manhole cover characteristics including the level difference between manhole cover and pavement, the pavement condition over the manhole cover, and the size of the manhole cover can significantly affect motorcycle driver maneuvers. Other factors, including traffic conditions, lane width, motorcycle speed, and loading conditions, also have significant effects on motorcycle driver maneuvers. To reduce the effects and potential risks from the manhole covers, highway authorities not only need to make sure that any newly installed manhole covers are as level as possible but also need to regularly maintain all the manhole covers to ensure that they are in good condition. In the long run, the size of manhole covers should be kept as small as possible so that the impact of manhole covers on motorcycle drivers can be effectively reduced. Supplemental materials are available for this article. Go to the publisher

  8. Effect of a hybrid maneuver in treating posterior canal benign paroxysmal positional vertigo.

    Science.gov (United States)

    Badawy, Wanees M A; Gad El-Mawla, Ebtessam K; Chedid, Ahmed E F; Mustafa, Ahmed H A

    2015-02-01

    Benign paroxysmal positional vertigo (BPPV) is the most common disorder of the vestibular system of the inner ear, which is a vital part of maintaining balance. Although the efficacy of the Epley maneuver-also known as the canalith repositioning maneuver (CRM)-is well established, data comparing CRM versus a hybrid treatment are lacking. The purpose of this study was to determine the effect of a hybrid treatment, the Gans repositioning maneuver (GRM) either with or without postmaneuver restrictions, compared with CRM on treatment of posterior canal BPPV (PC-BPPV). Study design was a randomized controlled trial. A total of 45 patients (30 males and 15 females) with unilateral PC-BPPV were randomly allocated to one of three equal groups on the basis of the date of the first visit with matched assignment for gender: a GRMR group (GRM with postmaneuver restrictions), a GRM group, and a CRM group. Patients received weekly administration of the maneuver until resolution of symptoms. The Dix-Hallpike test was performed before treatment at every appointment, and finally after 1 mo from the last maneuver. Nystagmus duration and vertigo intensity were recorded. The supine roll test was performed in case the Dix-Hallpike test was negative to test otoconial migration. Data were analyzed with repeated-measures analysis of variance, paired t-tests with a Bonferroni correction, and the Spearman rank correlation coefficient. All patients showed improvement within the groups, and PC-BPPV symptoms were resolved by an average of 2, 1.7, and 1.6 maneuvers for GRMR, GRM, and CRM, respectively, with no statistical differences among the three groups (p > 0.05). Only two patients had recurrence, and one patient had horizontal BPPV at 1 mo follow-up. We demonstrated that the GRM as a new treatment is effective in treating PC-BPPV with no benefits to postmaneuver restrictions. American Academy of Audiology.

  9. Head CT scan

    Science.gov (United States)

    ... scan - orbits; CT scan - sinuses; Computed tomography - cranial; CAT scan - brain ... head size in children Changes in thinking or behavior Fainting Headache, when you have certain other signs ...

  10. Bottom head assembly

    International Nuclear Information System (INIS)

    Fife, A.B.

    1998-01-01

    A bottom head dome assembly is described which includes, in one embodiment, a bottom head dome and a liner configured to be positioned proximate the bottom head dome. The bottom head dome has a plurality of openings extending there through. The liner also has a plurality of openings extending there through, and each liner opening aligns with a respective bottom head dome opening. A seal is formed, such as by welding, between the liner and the bottom head dome to resist entry of water between the liner and the bottom head dome at the edge of the liner. In the one embodiment, a plurality of stub tubes are secured to the liner. Each stub tube has a bore extending there through, and each stub tube bore is coaxially aligned with a respective liner opening. A seat portion is formed by each liner opening for receiving a portion of the respective stub tube. The assembly also includes a plurality of support shims positioned between the bottom head dome and the liner for supporting the liner. In one embodiment, each support shim includes a support stub having a bore there through, and each support stub bore aligns with a respective bottom head dome opening. 2 figs

  11. Maneuver Acoustic Flight Test of the Bell 430 Helicopter Data Report

    Science.gov (United States)

    Watts, Michael E.; Greenwood, Eric; Smith, Charles D.; Snider, Royce; Conner, David A.

    2014-01-01

    A cooperative ight test by NASA, Bell Helicopter and the U.S. Army to characterize the steady state acoustics and measure the maneuver noise of a Bell Helicopter 430 aircraft was accomplished. The test occurred during June/July 2011 at Eglin Air Force Base, Florida. This test gathered a total of 410 test points over 10 test days and compiled an extensive database of dynamic maneuver measurements. Three microphone arrays with up to 31 microphon. es in each were used to acquire acoustic data. Aircraft data included Differential Global Positioning System, aircraft state and rotor state information. This paper provides an overview of the test and documents the data acquired.

  12. Catheter Entrapment During Posterior Mitral Leaflet Pushing Maneuver for MitraClip Implantation.

    Science.gov (United States)

    Castrodeza, Javier; Amat-Santos, Ignacio J; Tobar, Javier; Varela-Falcón, Luis H

    2016-06-01

    MitraClip (Abbott Vascular) therapy has been reported to be an effective procedure for mitral regurgitation, especially in high-risk patients. Recently, the novel pushing maneuver technique has been described for approaching restricted and short posterior leaflets with a pigtail catheter in order to facilitate grasping of the clip. However, complications or unexpected situations may occur. We report the case of an 84-year-old patient who underwent MitraClip implantation wherein the pushing maneuver was complicated by the clip accidentally gripping the pigtail catheter along with the two leaflets.

  13. EQUATORIAL SUPERROTATION ON TIDALLY LOCKED EXOPLANETS

    International Nuclear Information System (INIS)

    Showman, Adam P.; Polvani, Lorenzo M.

    2011-01-01

    The increasing richness of exoplanet observations has motivated a variety of three-dimensional (3D) atmospheric circulation models of these planets. Under strongly irradiated conditions, models of tidally locked, short-period planets (both hot Jupiters and terrestrial planets) tend to exhibit a circulation dominated by a fast eastward, or 'superrotating', jet stream at the equator. When the radiative and advection timescales are comparable, this phenomenon can cause the hottest regions to be displaced eastward from the substellar point by tens of degrees longitude. Such an offset has been subsequently observed on HD 189733b, supporting the possibility of equatorial jets on short-period exoplanets. Despite its relevance, however, the dynamical mechanisms responsible for generating the equatorial superrotation in such models have not been identified. Here, we show that the equatorial jet results from the interaction of the mean flow with standing Rossby waves induced by the day-night thermal forcing. The strong longitudinal variations in radiative heating-namely intense dayside heating and nightside cooling-trigger the formation of standing, planetary-scale equatorial Rossby and Kelvin waves. The Rossby waves develop phase tilts that pump eastward momentum from high latitudes to the equator, thereby inducing equatorial superrotation. We present an analytic theory demonstrating this mechanism and explore its properties in a hierarchy of one-layer (shallow-water) calculations and fully 3D models. The wave-mean-flow interaction produces an equatorial jet whose latitudinal width is comparable to that of the Rossby waves, namely the equatorial Rossby deformation radius modified by radiative and frictional effects. For conditions typical of synchronously rotating hot Jupiters, this length is comparable to a planetary radius, explaining the broad scale of the equatorial jet obtained in most hot-Jupiter models. Our theory illuminates the dependence of the equatorial jet

  14. El concepto de Derecho en Locke

    Directory of Open Access Journals (Sweden)

    Diego Alejandro Fernández Peychaux

    2011-01-01

    Full Text Available El siguiente artículo aspira a ser un aporte para la comprensión del modo en que John Locke establece la relación entre los hombres y la sociedad. De acuerdo con la tradición contractualista en la que el autor se inscribe, se pretende recorrer un camino con dos etapas. En la primera, se busca establecer bien el significado del concepto de derecho, bien su relación con los deberes que surgen de la ley de naturaleza. En un segundo momento, se buscará identificar la relación existente entre los derechos/deberes y el concepto de inalienabilidad, para así comprender no ya la relación interna de los derechos/deberes individuales, sino cómo interactúan estos con los del prójimo y la comunidad en la que viven los hombres. Para ello se buscará argumentar que la inalienabilidad de los derechos del hombre, excluido el derecho a la vida, no se fundamenta en el propio derecho, sino en la relación de este con el bien más fundamental que buscan preservar, n.b. autopreservación. De este modo, se establece una suerte de escala de derechos, donde a medida que se desciende se amplía el poder de enajenación, siempre y cuando represente un aumento de las expectativas de mejorar las posibilidades de preservación.

  15. Effects of the Eccentricity of a Perturbing Third Body on the Orbital Correction Maneuvers of a Spacecraft

    Directory of Open Access Journals (Sweden)

    R. C. Domingos

    2014-01-01

    Full Text Available The fuel consumption required by the orbital maneuvers when correcting perturbations on the orbit of a spacecraft due to a perturbing body was estimated. The main goals are the measurement of the influence of the eccentricity of the perturbing body on the fuel consumption required by the station keeping maneuvers and the validation of the averaged methods when applied to the problem of predicting orbital maneuvers. To study the evolution of the orbits, the restricted elliptic three-body problem and the single- and double-averaged models are used. Maneuvers are made by using impulsive and low thrust maneuvers. The results indicated that the averaged models are good to make predictions for the orbital maneuvers when the spacecraft is in a high inclined orbit. The eccentricity of the perturbing body plays an important role in increasing the effects of the perturbation and the fuel consumption required for the station keeping maneuvers. It is shown that the use of more frequent maneuvers decreases the annual cost of the station keeping to correct the orbit of a spacecraft. An example of an eccentric planetary system of importance to apply the present study is the dwarf planet Haumea and its moons, one of them in an eccentric orbit.

  16. 78 FR 11555 - Special Conditions: Embraer S.A., Model EMB-550 Airplane; Design Roll Maneuver for Electronic...

    Science.gov (United States)

    2013-02-19

    ... Law 92-574, the ``Noise Control Act of 1972.'' The FAA issues special conditions, as defined in 14 CFR...; Design Roll Maneuver for Electronic Flight Controls AGENCY: Federal Aviation Administration (FAA), DOT... design roll maneuver for electronic flight controls, specifically an electronic flight control system...

  17. 77 FR 70384 - Special Conditions: Embraer S.A., Model EMB-550 Airplane; Design Roll Maneuver for Electronic...

    Science.gov (United States)

    2012-11-26

    ... Law 92-574, the ``Noise Control Act of 1972.'' The FAA issues special conditions, as defined in 14 CFR... Maneuver for Electronic Flight Controls AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice... design roll maneuver for electronic flight controls, specifically an electronic flight control system...

  18. Pressure applied by the healthcare staff on a cricoids cartilage simulator during Sellick's maneuver in rapid sequence intubation

    NARCIS (Netherlands)

    J.A. Calvache (Jose Andrés); L.C.B. Sandoval (Luz); W.A. Vargas (William Andres)

    2013-01-01

    textabstractBackground: Sellick's maneuver or cricoid pressure is a strategy used to prevent bronchoaspiration during the rapid intubation sequence. Several studies have described that the force required for an adequate maneuver is of 2.5-3.5 kg. The purpose of this paper was to determine the force

  19. Computed Tomography (CT) -- Head

    Medline Plus

    Full Text Available ... Physician Resources Professions Site Index A-Z Computed Tomography (CT) - Head Computed tomography (CT) of the head uses special x-ray equipment ... story here Images × Image Gallery Patient undergoing computed tomography (CT) scan. View full size with caption Pediatric Content ...

  20. Computed Tomography (CT) -- Head

    Medline Plus

    Full Text Available ... Computed tomography (CT) of the head uses special x-ray equipment to help assess head injuries, severe headaches, ... is a diagnostic medical test that, like traditional x-rays, produces multiple images or pictures of the inside ...

  1. Reactor head shielding apparatus

    International Nuclear Information System (INIS)

    Schukei, G.E.; Roebelen, G.J.

    1992-01-01

    This patent describes a nuclear reactor head shielding apparatus for mounting on spaced reactor head lifting members radially inwardly of the head bolts. It comprises a frame of sections for mounting on the lifting members and extending around the top central area of the head, mounting means for so mounting the frame sections, including downwardly projecting members on the frame sections and complementary upwardly open recessed members for fastening to the lifting members for receiving the downwardly projecting members when the frame sections are lowered thereto with lead shielding supported thereby on means for hanging lead shielding on the frame to minimize radiation exposure or personnel working with the head bolts or in the vicinity thereof

  2. Huang's three-step maneuver shortens the learning curve of laparoscopic spleen-preserving splenic hilar lymphadenectomy.

    Science.gov (United States)

    Huang, Chang-Ming; Huang, Ze-Ning; Zheng, Chao-Hui; Li, Ping; Xie, Jian-Wei; Wang, Jia-Bin; Lin, Jian-Xian; Jun, Lu; Chen, Qi-Yue; Cao, Long-Long; Lin, Mi; Tu, Ru-Hong

    2017-12-01

    The goal of this study was to investigate the difference between the learning curves of different maneuvers in laparoscopic spleen-preserving splenic hilar lymphadenectomy for advanced upper gastric cancer. From January 2010 to April 2014, 53 consecutive patients who underwent laparoscopic spleen-preserving splenic hilar lymphadenectomy via the traditional-step maneuver (group A) and 53 consecutive patients via Huang's three-step maneuver (group B) were retrospectively analyzed. No significant difference in patient characteristics were found between the two groups. The learning curves of groups A and B were divided into phase 1 (1-43 cases and 1-30 cases, respectively) and phase 2 (44-53 cases and 31-53 cases, respectively). Compared with group A, the dissection time, bleeding loss and vascular injury were significantly decreased in group B. No significant differences in short-term outcomes were found between the two maneuvers. The multivariate analysis indicated that the body mass index, short gastric vessels, splenic artery type and maneuver were significantly associated with the dissection time in group B. No significant difference in the survival curve was found between the maneuvers. The learning curve of Huang's three-step maneuver was shorter than that of the traditional-step maneuver, and the former represents an ideal maneuver for laparoscopic spleen-preserving splenic hilar lymphadenectomy.To shorten the learning curve at the beginning of laparoscopic spleen-preserving splenic hilar lymphadenectomy, beginners should beneficially use Huang's three-step maneuver and select patients with advanced upper gastric cancer with a body mass index of less than 25 kg/m 2 and the concentrated type of splenic artery. Copyright © 2017. Published by Elsevier Ltd.

  3. Multislice spiral computed tomography to determine the effects of a recruitment maneuver in experimental lung injury

    Energy Technology Data Exchange (ETDEWEB)

    Henzler, Dietrich; Rossaint, Rolf [University Hospital, RWTH Aachen, Anesthesiology Department, Aachen (Germany); Mahnken, Andreas H.; Wildberger, Joachim E.; Guenther, Rolf W. [University Hospital of the RWTH Aachen, Clinic of Diagnostic Radiology, Aachen (Germany); Kuhlen, Ralf [University Hospital of the RWTH Aachen, Operative Intensive Care Department, Aachen (Germany)

    2006-06-15

    Although recruitment of atelectatic lung is a common aim in acute respiratory distress syndrome (ARDS), the effects of a recruitment maneuver have not been assessed quantitatively. By multislice spiral CT (MSCT), we analyzed the changes in lung volumes calculated from the changes in the CT values of hyperinflated (V{sub HYP}), normally (V{sub NORM}), poorly (V{sub POOR}) and nonaerated (V{sub NON}) lung in eight mechanically ventilated pigs with saline lavage-induced acute lung injury before and after a recruitment maneuver. This was compared to single slice analysis near the diaphragm. The increase in aerated lung was mainly for V{sub POOR} and the less in V{sub NORM}. Total lung volume and intrathoracic gas increased. No differences were found for tidal volumes measured by spirometry or determined by CT. The inspiratory-expiratory volume differences were not different after the recruitment maneuver in V{sub NON} (from 62{+-}18 ml to 43{+-}26 ml, P=0.114), and in V{sub NORM} (from 216{+-}51 ml to 251{+-}37 ml, P=0.102). Single slice analysis significantly underestimated the increase in normally and poorly aerated lung. Quantitative analysis of lung volumes by whole lung MSCT revealed the increase of poorly aerated lung as the main mechanism of a standard recruitment maneuver. MSCT can provide additional information as compared to single slice CT. (orig.)

  4. Cooperative maneuvering in close environments among cybercars and dual-mode cars

    NARCIS (Netherlands)

    Milanés, V.; Alonso, J.; Bouraoui, L.; Ploeg, J.

    2011-01-01

    This paper describes the results of vehicle-to-vehicle (V2V) and infrastructure-to-vehicle (I2V) experiments implementing cooperative maneuvering for three different vehicles driving automatically. The cars used were cybercars from the Institut National de Recherche en Informatique et Automatique

  5. The Prospect of Responsive Spacecraft Using Aeroassisted, Trans-Atmospheric Maneuvers

    Science.gov (United States)

    2014-06-19

    99 V. Design of Experiments Approach to Atmospheric Skip Entry Maneuver Optimization .....100 Chapter Overview...Transfer Diagram .................................................................................................11 3.1. Comparison of Geocentric ...Comparison of Geocentric /Geodetic Latitude for Apollo 10 (2-Gravity Model, Fourth-Order Runge-Kutta Solver

  6. Conflict Resolution Performance in an Experimental Study of En Route Free Maneuvering Operations

    Science.gov (United States)

    Doble, Nathan A.; Barhydt, Richard; Hitt, James M., II

    2005-01-01

    NASA has developed a far-term air traffic management concept, termed Distributed Air/Ground Traffic Management (DAG-TM). One component of DAG-TM, En Route Free Maneuvering, allows properly trained flight crews of equipped autonomous aircraft to assume responsibility for separation from other autonomous aircraft and from Instrument Flight Rules (IFR) aircraft. Ground-based air traffic controllers continue to separate IFR traffic and issue flow management constraints to all aircraft. To examine En Route Free Maneuvering operations, a joint human-in-the-loop experiment was conducted in summer 2004 at the NASA Ames and Langley Research Centers. Test subject pilots used desktop flight simulators to resolve traffic conflicts and adhere to air traffic flow constraints issued by subject controllers. The experimental airspace integrated both autonomous and IFR aircraft at varying traffic densities. This paper presents a subset of the En Route Free Maneuvering experimental results, focusing on airborne and ground-based conflict resolution, and the effects of increased traffic levels on the ability of pilots and air traffic controllers to perform this task. The results show that, in general, increases in autonomous traffic do not significantly impact conflict resolution performance. In addition, pilot acceptability of autonomous operations remains high throughout the range of traffic densities studied. Together with previously reported findings, these results continue to support the feasibility of the En Route Free Maneuvering component of DAG-TM.

  7. 46 CFR 35.20-40 - Maneuvering characteristics-T/OC.

    Science.gov (United States)

    2010-10-01

    ... for the normal load and normal ballast condition for: (1) Calm weather—wind 10 knots or less, calm sea... response of the (name of the vessel) may be different from those listed above if any of the following conditions, upon which the maneuvering information is based, are varied: (1) Calm weather—wind 10 knots or...

  8. Linearity of electrical impedance tomography during maximum effort breathing and forced expiration maneuvers.

    Science.gov (United States)

    Ngo, Chuong; Leonhardt, Steffen; Zhang, Tony; Lüken, Markus; Misgeld, Berno; Vollmer, Thomas; Tenbrock, Klaus; Lehmann, Sylvia

    2017-01-01

    Electrical impedance tomography (EIT) provides global and regional information about ventilation by means of relative changes in electrical impedance measured with electrodes placed around the thorax. In combination with lung function tests, e.g. spirometry and body plethysmography, regional information about lung ventilation can be achieved. Impedance changes strictly correlate with lung volume during tidal breathing and mechanical ventilation. Initial studies presumed a correlation also during forced expiration maneuvers. To quantify the validity of this correlation in extreme lung volume changes during forced breathing, a measurement system was set up and applied on seven lung-healthy volunteers. Simultaneous measurements of changes in lung volume using EIT imaging and pneumotachography were obtained with different breathing patterns. Data was divided into a synchronizing phase (spontaneous breathing) and a test phase (maximum effort breathing and forced maneuvers). The EIT impedance changes correlate strictly with spirometric data during slow breathing with increasing and maximum effort ([Formula: see text]) and during forced expiration maneuvers ([Formula: see text]). Strong correlations in spirometric volume parameters [Formula: see text] ([Formula: see text]), [Formula: see text]/FVC ([Formula: see text]), and flow parameters PEF, [Formula: see text], [Formula: see text], [Formula: see text] ([Formula: see text]) were observed. According to the linearity during forced expiration maneuvers, EIT can be used during pulmonary function testing in combination with spirometry for visualisation of regional lung ventilation.

  9. Multislice spiral computed tomography to determine the effects of a recruitment maneuver in experimental lung injury

    International Nuclear Information System (INIS)

    Henzler, Dietrich; Rossaint, Rolf; Mahnken, Andreas H.; Wildberger, Joachim E.; Guenther, Rolf W.; Kuhlen, Ralf

    2006-01-01

    Although recruitment of atelectatic lung is a common aim in acute respiratory distress syndrome (ARDS), the effects of a recruitment maneuver have not been assessed quantitatively. By multislice spiral CT (MSCT), we analyzed the changes in lung volumes calculated from the changes in the CT values of hyperinflated (V HYP ), normally (V NORM ), poorly (V POOR ) and nonaerated (V NON ) lung in eight mechanically ventilated pigs with saline lavage-induced acute lung injury before and after a recruitment maneuver. This was compared to single slice analysis near the diaphragm. The increase in aerated lung was mainly for V POOR and the less in V NORM . Total lung volume and intrathoracic gas increased. No differences were found for tidal volumes measured by spirometry or determined by CT. The inspiratory-expiratory volume differences were not different after the recruitment maneuver in V NON (from 62±18 ml to 43±26 ml, P=0.114), and in V NORM (from 216±51 ml to 251±37 ml, P=0.102). Single slice analysis significantly underestimated the increase in normally and poorly aerated lung. Quantitative analysis of lung volumes by whole lung MSCT revealed the increase of poorly aerated lung as the main mechanism of a standard recruitment maneuver. MSCT can provide additional information as compared to single slice CT. (orig.)

  10. Associating Crash Avoidance Maneuvers with Driver Attributes and Accident Characteristics: A Mixed Logit Model Approach

    DEFF Research Database (Denmark)

    Kaplan, Sigal; Prato, Carlo Giacomo

    2012-01-01

    as from the key role of the ability of drivers to perform effective corrective maneuvers for the success of automated in-vehicle warning and driver assistance systems. The analysis is conducted by means of a mixed logit model that accommodates correlations across alternatives and heteroscedasticity. Data...

  11. Leveraging Manet and Mobile Devices in Ship-to-Objective Maneuver and Expeditionary MAGTF Operations

    Science.gov (United States)

    2014-09-01

    support and firepower. ECO allows for the Marine Corps to deploy a lower- level maneuver unit as an economy of force measure to assert combat power over...to the Global Information Grid ( GIG ) is the course of action the Marine Corps should adopt (Price & McHuen, 2009). My proposed research addresses

  12. Effect of different body postures on the pressures generated during an L-1 maneuver.

    Science.gov (United States)

    Williams, C A; Lind, A R; Wiley, R L; Douglas, J E; Miller, G

    1988-10-01

    Changes in blood pressure, intrathoracic pressure, heart rate and the electromyographic activity of various muscle groups were determined while nine male subjects performed 15-s L-1 straining maneuvers at four spine-to-thigh angles (70, 84, 94, and 105 degrees) and two seatback angles (30 and 60 degrees). There was no significant difference between the changes in these variables due to the different body positions. At the onset of the L-1, arterial pressure immediately increased to 195 +/- 5 mm Hg, but fell progressively during the next 5 s to 160 +/- 5 mm Hg. It remained constant during the next 5 s of the maneuver and then recovered to 180 +/- mm Hg during the last 5 s of the maneuver. Esophageal pressure followed essentially the same pattern of response, but heart rate progressively increased during the entire L-1. No one muscle group was utilized more than another. Inflation of an anti-G suit to 4 PSI had no effect on the variables measured. Generation of high arterial pressures during L-1 maneuvers is transitory and not affected either positively or negatively by altering subject body position.

  13. Evolution of the Generic Lock System at Jefferson Lab

    International Nuclear Information System (INIS)

    Brian Bevins; Yves Roblin

    2003-01-01

    The Generic Lock system is a software framework that allows highly flexible feedback control of large distributed systems. It allows system operators to implement new feedback loops between arbitrary process variables quickly and with no disturbance to the underlying control system. Several different types of feedback loops are provided and more are being added. This paper describes the further evolution of the system since it was first presented at ICALEPCS 2001 and reports on two years of successful use in accelerator operations. The framework has been enhanced in several key ways. Multiple-input, multiple-output (MIMO) lock types have been added for accelerator orbit and energy stabilization. The general purpose Proportional-Integral-Derivative (PID) locks can now be tuned automatically. The generic lock server now makes use of the Proxy IOC (PIOC) developed at Jefferson Lab to allow the locks to be monitored from any EPICS Channel Access aware client. (Previously clients had to be Cdev aware.) The dependency on the Qt XML parser has been replaced with the freely available Xerces DOM parser from the Apache project

  14. Locked-in: the syndrome as depicted in literature.

    Science.gov (United States)

    Haan, Joost

    2013-01-01

    Protagonists who are locked-in can be found throughout fiction, probably because being locked-in serves as a strong philosophical metaphor for human existence. In this chapter, three protagonists who are locked-in due to physical/medical reasons will be described. The fictitious stories of Noirtier from The Count of Monte Cristo by Alexandre Dumas and that of Madame Raquin from Thérèse Raquin by Émile Zola are followed by the real-life story of Jean-Dominique Bauby's The Diving Bell and the Butterfly. Dumas' Noirtier is considered the first description of the locked-in syndrome in literature, and Madame Raquin appears to be locked-in also, but her description leaves many questions. Bauby's autopathography is chosen from many several similar discourses as it contains cross-references to Noirtier, Dumas' prototype of the syndrome, but also because it is of high literary value. The similarities and remarkable differences between these three case reports of this existentialistically important state of being will be highlighted, with an emphasis on the focus of their narratives. © 2013 Elsevier B.V. All rights reserved.

  15. Mutual phase-locking of planar nano-oscillators

    Directory of Open Access Journals (Sweden)

    K. Y. Xu

    2014-06-01

    Full Text Available Characteristics of phase-locking between Gunn effect-based planar nano-oscillators are studied using an ensemble Monte Carlo (EMC method. Directly connecting two oscillators in close proximity, e.g. with a channel distance of 200 nm, only results in incoherent oscillations. In order to achieve in-phase oscillations, additional considerations must be taken into account. Two coupling paths are shown to exist between oscillators. One coupling path results in synchronization and the other results in anti-phase locking. The coupling strength through these two paths can be adjusted by changing the connections between oscillators. When two identical oscillators are in the anti-phase locking regime, fundamental components of oscillations are cancelled. The resulting output consists of purely second harmonic oscillations with a frequency of about 0.66 THz. This type of second harmonic generation is desired for higher frequency applications since no additional filter system is required. This transient phase-locking process is further analyzed using Adler's theory. The locking range is extracted, and a criterion for the channel length difference required for realizing phased arrays is obtained. This work should aid in designing nano-oscillator arrays for high power applications and developing directional transmitters for wireless communications.

  16. APR1400 Locked Rotor Transient Analysis using KNAP

    International Nuclear Information System (INIS)

    Lee, Dong-Hyuk; Kim, Yo-Han; Ha, Sang Jun

    2007-01-01

    KEPRI (Korea Electric Power Research Institute) has developed safety analysis methodology for non-LOCA (Loss Of Coolant Accident) analysis of OPR1000 (Optimized Power Reactor 1000, formerly KSNP). The new methodology, named KNAP (Korea Non-LOCA Analysis Package), uses RETRAN as the main system analysis code for most transients. For locked rotor transient DNBR analysis, UNICORN-TM code is used. UNICORN-TM is the unified code of RETRAN, MASTER and TORC. The UNICORN-TM has 1-D and 3-D neutron kinetics calculation capability. For locked rotor DNBR analysis, 1-D neutron kinetics is used. In this paper, we apply KNAP methodology to APR1400 (Advanced Power Reactor 1400) locked rotor analysis and compare the results with those in the APR1400 SSAR(Standard Safety Analysis Report). The locked rotor transient is one of the 'decrease in reactor coolant system flow rate' events and the results are typically described in the chapter 15.3.3 of SAR (Safety Analysis Report). In this study, to confirm the applicability of the KNAP methodology and code system to APR1400, locked rotor transient is analyzed using UNICORN-TM code and the results are compared with those from APR1400 SSAR

  17. Complication with Removal of a Lumbar Spinal Locking Plate

    Directory of Open Access Journals (Sweden)

    Brooke Crawford

    2015-01-01

    Full Text Available Introduction. The use of locking plate technology for anterior lumbar spinal fusion has increased stability of the vertebral fusion mass over traditional nonconstrained screw and plate systems. This case report outlines a complication due to the use of this construct. Case. A patient with a history of L2 corpectomy and anterior spinal fusion presented with discitis at the L4/5 level and underwent an anterior lumbar interbody fusion (ALIF supplemented with a locking plate placed anterolaterally for stability. Fifteen months after the ALIF procedure, he returned with a hardware infection. He underwent debridement of the infection site and removal of hardware. Results. Once hardware was exposed, removal of the locking plate screws was only successful in one out of four screws using a reverse thread screw removal device. Three of the reverse thread screw removal devices broke in attempt to remove the subsequent screws. A metal cutting drill was then used to break hoop stresses associated with the locking device and the plate was removed. Conclusion. Anterior locking plates add significant stability to an anterior spinal fusion mass. However, removal of this hardware can be complicated by the inherent properties of the design with significant risk of major vascular injury.

  18. APR1400 Locked Rotor Transient Analysis using KNAP

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Dong-Hyuk; Kim, Yo-Han; Ha, Sang Jun [Korea Electric Power Research Institute, Daejeon (Korea, Republic of)

    2007-07-01

    KEPRI (Korea Electric Power Research Institute) has developed safety analysis methodology for non-LOCA (Loss Of Coolant Accident) analysis of OPR1000 (Optimized Power Reactor 1000, formerly KSNP). The new methodology, named KNAP (Korea Non-LOCA Analysis Package), uses RETRAN as the main system analysis code for most transients. For locked rotor transient DNBR analysis, UNICORN-TM code is used. UNICORN-TM is the unified code of RETRAN, MASTER and TORC. The UNICORN-TM has 1-D and 3-D neutron kinetics calculation capability. For locked rotor DNBR analysis, 1-D neutron kinetics is used. In this paper, we apply KNAP methodology to APR1400 (Advanced Power Reactor 1400) locked rotor analysis and compare the results with those in the APR1400 SSAR(Standard Safety Analysis Report). The locked rotor transient is one of the 'decrease in reactor coolant system flow rate' events and the results are typically described in the chapter 15.3.3 of SAR (Safety Analysis Report). In this study, to confirm the applicability of the KNAP methodology and code system to APR1400, locked rotor transient is analyzed using UNICORN-TM code and the results are compared with those from APR1400 SSAR.

  19. Doppler ultrasonography measurement of hepatic hemodynamics during Valsalva maneuver: healthy volunteer study

    Directory of Open Access Journals (Sweden)

    Dong-Ho Bang

    2015-01-01

    Full Text Available Purpose: The aim of our study was to assess the hemodynamic change of liver during the Valsalva maneuver using Doppler ultrasonography. Methods: Thirty healthy men volunteers were enrolled (mean age, 25.5±3.64 years. The diameter, minimal and maximal velocities, and volume flow of intrahepatic inferior vena cava (IVC, middle hepatic vein (MHV, and right main portal vein (RMPV was measured during both rest and Valsalva maneuver. These changes were compared using paired t-test. Results: The mean diameters (cm of the intrahepatic IVC at rest and Valsalva maneuver were 1.94±0.40 versus 0.56±0.66 (P<0.001. The mean diameter (cm, minimal velocity (cm/sec, maximal velocity (cm/sec, and volume flow (mL/min of MHV at rest and Valsalva maneuver were 0.60±0.15 versus 0.38±0.20 (P<0.001, -7.98±5.47 versus 25.74±13.13 (P<0.001, 21.34±6.89 versus 35.12±19.95 (P=0.002, and 106.94±97.65 versus 153.90±151.80 (P=0.014, respectively. Those of RMPV at rest and Valsalva maneuver were 0.78±0.21 versus 0.76±0.20 (P=0.485, 20.21±8.22 versus 18.73±7.43 (P=0.351, 26.79±8.85 versus 24.93±9.91 (P=0.275, and 391.52±265.63 versus 378.43±239.36 (P=0.315, respectively. Conclusion: The blood flow velocity and volume flow of MHV increased significantly during Valsalva maneuver. These findings suggest that hepatic vein might play an important role to maintain venous return to the heart during the maneuver.

  20. Doppler ultrasonography measuement of hepatic hemodynamics during Valsalva maneuver: healthy volunteers study

    Energy Technology Data Exchange (ETDEWEB)

    Bang, Dong Ho; Son, Young Jin; Lee, Young Hwan; Yoon, Kwon Ha [Dept. of Radiology, Wonkwang University School of Medicine, Iksan (Korea, Republic of)

    2015-01-15

    The aim of our study was to assess the hemodynamic change of liver during the Valsalva maneuver using Doppler ultrasonography. Thirty healthy men volunteers were enrolled (mean age, 25.5±3.64 years). The diameter, minimal and maximal velocities, and volume flow of intrahepatic inferior vena cava (IVC), middle hepatic vein (MHV), and right main portal vein (RMPV) was measured during both rest and Valsalva maneuver. These changes were compared using paired t-test. The mean diameters (cm) of the intrahepatic IVC at rest and Valsalva maneuver were 1.94±0.40 versus 0.56±0.66 (P<0.001). The mean diameter (cm), minimal velocity (cm/sec), maximal velocity (cm/sec), and volume flow (mL/min) of MHV at rest and Valsalva maneuver were 0.60±0.15 versus 0.38±0.20 (P<0.001), -7.98±5.47 versus 25.74±13.13 (P<0.001), 21.34±6.89 versus 35.12±19.95 (P=0.002), and 106.94±97.65 versus 153.90±151.80 (P=0.014), respectively. Those of RMPV at rest and Valsalva maneuver were 0.78±0.21 versus 0.76±0.20 (P=0.485), 20.21±8.22 versus 18.73±7.43 (P=0.351), 26.79±8.85 versus 24.93±9.91 (P=0.275), and 391.52±265.63 versus 378.43±239.36 (P=0.315), respectively. The blood flow velocity and volume flow of MHV increased significantly during Valsalva maneuver. These findings suggest that hepatic vein might play an important role to maintain venous return to the heart during the maneuver.

  1. CLIMATE INSTABILITY ON TIDALLY LOCKED EXOPLANETS

    International Nuclear Information System (INIS)

    Kite, Edwin S.; Manga, Michael; Gaidos, Eric

    2011-01-01

    Feedbacks that can destabilize the climates of synchronously rotating rocky planets may arise on planets with strong day-night surface temperature contrasts. Earth-like habitable planets maintain stable surface liquid water over geologic time. This requires equilibrium between the temperature-dependent rate of greenhouse-gas consumption by weathering, and greenhouse-gas resupply by other processes. Detected small-radius exoplanets, and anticipated M-dwarf habitable-zone rocky planets, are expected to be in synchronous rotation (tidally locked). In this paper, we investigate two hypothetical feedbacks that can destabilize climate on planets in synchronous rotation. (1) If small changes in pressure alter the temperature distribution across a planet's surface such that the weathering rate goes up when the pressure goes down, a runaway positive feedback occurs involving increasing weathering rate near the substellar point, decreasing pressure, and increasing substellar surface temperature. We call this feedback enhanced substellar weathering instability (ESWI). (2) When decreases in pressure increase the fraction of surface area above the melting point (through reduced advective cooling of the substellar point), and the corresponding increase in volume of liquid causes net dissolution of the atmosphere, a further decrease in pressure will occur. This substellar dissolution feedback can also cause a runaway climate shift. We use an idealized energy balance model to map out the conditions under which these instabilities may occur. In this simplified model, the weathering runaway can shrink the habitable zone and cause geologically rapid 10 3 -fold atmospheric pressure shifts within the habitable zone. Mars may have undergone a weathering runaway in the past. Substellar dissolution is usually a negative feedback or weak positive feedback on changes in atmospheric pressure. It can only cause runaway changes for small, deep oceans and highly soluble atmospheric gases. Both

  2. CLIMATE INSTABILITY ON TIDALLY LOCKED EXOPLANETS

    Energy Technology Data Exchange (ETDEWEB)

    Kite, Edwin S.; Manga, Michael [Department of Earth and Planetary Science, University of California at Berkeley, CA 94720 (United States); Gaidos, Eric, E-mail: edwin.kite@gmail.com [Department of Geology and Geophysics, University of Hawaii at Manoa, Honolulu, HI 96822 (United States)

    2011-12-10

    Feedbacks that can destabilize the climates of synchronously rotating rocky planets may arise on planets with strong day-night surface temperature contrasts. Earth-like habitable planets maintain stable surface liquid water over geologic time. This requires equilibrium between the temperature-dependent rate of greenhouse-gas consumption by weathering, and greenhouse-gas resupply by other processes. Detected small-radius exoplanets, and anticipated M-dwarf habitable-zone rocky planets, are expected to be in synchronous rotation (tidally locked). In this paper, we investigate two hypothetical feedbacks that can destabilize climate on planets in synchronous rotation. (1) If small changes in pressure alter the temperature distribution across a planet's surface such that the weathering rate goes up when the pressure goes down, a runaway positive feedback occurs involving increasing weathering rate near the substellar point, decreasing pressure, and increasing substellar surface temperature. We call this feedback enhanced substellar weathering instability (ESWI). (2) When decreases in pressure increase the fraction of surface area above the melting point (through reduced advective cooling of the substellar point), and the corresponding increase in volume of liquid causes net dissolution of the atmosphere, a further decrease in pressure will occur. This substellar dissolution feedback can also cause a runaway climate shift. We use an idealized energy balance model to map out the conditions under which these instabilities may occur. In this simplified model, the weathering runaway can shrink the habitable zone and cause geologically rapid 10{sup 3}-fold atmospheric pressure shifts within the habitable zone. Mars may have undergone a weathering runaway in the past. Substellar dissolution is usually a negative feedback or weak positive feedback on changes in atmospheric pressure. It can only cause runaway changes for small, deep oceans and highly soluble atmospheric

  3. The free energy of locking a ring: Changing a deoxyribonucleoside to a locked nucleic acid.

    Science.gov (United States)

    Xu, You; Villa, Alessandra; Nilsson, Lennart

    2017-06-05

    Locked nucleic acid (LNA), a modified nucleoside which contains a bridging group across the ribose ring, improves the stability of DNA/RNA duplexes significantly, and therefore is of interest in biotechnology and gene therapy applications. In this study, we investigate the free energy change between LNA and DNA nucleosides. The transformation requires the breaking of the bridging group across the ribose ring, a problematic transformation in free energy calculations. To address this, we have developed a 3-step (easy to implement) and a 1-step protocol (more efficient, but more complicated to setup), for single and dual topologies in classical molecular dynamics simulations, using the Bennett Acceptance Ratio method to calculate the free energy. We validate the approach on the solvation free energy difference for the nucleosides thymidine, cytosine, and 5-methyl-cytosine. © 2017 The Authors. Journal of Computational Chemistry Published by Wiley Periodicals, Inc. © 2017 The Authors. Journal of Computational Chemistry Published by Wiley Periodicals, Inc.

  4. The Choice of the Maneuver of the Vessel’s Passing Considering the Coordination’s System of the Interactive Vessels and Their Dynamic Characteristics

    Directory of Open Access Journals (Sweden)

    Yevgen Volkov

    2017-03-01

    Full Text Available The maneuver of the altering course of the vessel is a more preferable to avoid a collision. Due to that the calculation of the parameters of the avoidance maneuver should be done considering the dynamic characteristics of the vessel in maneuvering. The paper analyzes the dynamic models of the vessel rotation motion in order to select more appropriate one for the calculation of avoidance maneuver of the vessel applying the altering of the course.

  5. A Digital Phase Lock Loop for an External Cavity Diode Laser

    Science.gov (United States)

    Wang, Xiao-Long; Tao, Tian-Jiong; Cheng, Bing; Wu, Bin; Xu, Yun-Fei; Wang, Zhao-Ying; Lin, Qiang

    2011-08-01

    A digital optical phase lock loop (OPLL) is implemented to synchronize the frequency and phase between two external cavity diode lasers (ECDL), generating Raman pulses for atom interferometry. The setup involves all-digital phase detection and a programmable digital proportional-integral-derivative (PID) loop in locking. The lock generates a narrow beat-note linewidth below 1 Hz and low phase-noise of 0.03rad2 between the master and slave ECDLs. The lock proves to be stable and robust, and all the locking parameters can be set and optimized on a computer interface with convenience, making the lock adaptable to various setups of laser systems.

  6. Parameter Identification of Ship Maneuvering Models Using Recursive Least Square Method Based on Support Vector Machines

    Directory of Open Access Journals (Sweden)

    Man Zhu

    2017-03-01

    Full Text Available Determination of ship maneuvering models is a tough task of ship maneuverability prediction. Among several prime approaches of estimating ship maneuvering models, system identification combined with the full-scale or free- running model test is preferred. In this contribution, real-time system identification programs using recursive identification method, such as the recursive least square method (RLS, are exerted for on-line identification of ship maneuvering models. However, this method seriously depends on the objects of study and initial values of identified parameters. To overcome this, an intelligent technology, i.e., support vector machines (SVM, is firstly used to estimate initial values of the identified parameters with finite samples. As real measured motion data of the Mariner class ship always involve noise from sensors and external disturbances, the zigzag simulation test data include a substantial quantity of Gaussian white noise. Wavelet method and empirical mode decomposition (EMD are used to filter the data corrupted by noise, respectively. The choice of the sample number for SVM to decide initial values of identified parameters is extensively discussed and analyzed. With de-noised motion data as input-output training samples, parameters of ship maneuvering models are estimated using RLS and SVM-RLS, respectively. The comparison between identification results and true values of parameters demonstrates that both the identified ship maneuvering models from RLS and SVM-RLS have reasonable agreements with simulated motions of the ship, and the increment of the sample for SVM positively affects the identification results. Furthermore, SVM-RLS using data de-noised by EMD shows the highest accuracy and best convergence.

  7. Does Shoe Collar Height Influence Ankle Joint Kinematics and Kinetics in Sagittal Plane Maneuvers?

    Science.gov (United States)

    Yang, Yang; Fang, Ying; Zhang, Xini; He, Junliang; Fu, Weijie

    2017-01-01

    The Objective of the study is to investigate the effects of basketball shoes with different collar heights on ankle kinematics and kinetics and athletic performance in different sagittal plane maneuvers. Twelve participants who wore high-top and low-top basketball shoes (hereafter, HS and LS, respectively) performed a weight-bearing dorsiflexion (WB-DF) maneuver, drop jumps (DJs), and lay-up jumps (LJs). Their sagittal plane kinematics and ground reaction forces were recorded using the Vicon motion capture system and Kistler force plates simultaneously. Moreover, ankle dorsiflexion and plantarflexion angles, moment, power, stiffness, and jump height were calculated. In the WB-DF test, the peak ankle dorsiflexion angle (p = 0.041) was significantly smaller in HS than in LS. Additionally, the peak ankle plantarflexion moment (p = 0.028) and power (p = 0.022) were significantly lower in HS than in LS during LJs but not during DJs. In both jumping maneuvers, no significant differences were found in the jump height or ankle kinematics between the two shoe types. According to the WB-DF test, increasing shoe collar height can effectively reduce the ankle range of motion in the sagittal plane. Although the HS did not restrict the flexion–extension performance of the ankle joint during two jumping maneuvers, an increased shoe collar height can reduce peak ankle plantarflexion moment and peak power during the push-off phase in LJs. Therefore, a higher shoe collar height should be used to circumvent effects on the partial kinetics of the ankle joint in the sagittal plane. Key points An increased shoe collar height effectively reduced ankle joint ROM in the sagittal plane in weight-bearing dorsiflexion maneuver. Shoe collar height did not affect sagittal plane ankle kinematics and had no effect on performance during realistic jumping. Shoe collar height can affect the ankle plantarflexion torque and peak power during the push-off phase in lay-up jump. PMID:29238255

  8. Concept of a Maneuvering Load Control System and Effect on the Fatigue Life Extension

    Directory of Open Access Journals (Sweden)

    N. Paletta

    Full Text Available Abstract This paper presents a methodology for the conceptual design of a Maneuver Load Control system taking into account the airframe flexibility. The system, when switched on, is able to minimize the bending moment augmentation at a wing station near the wing root during an unsteady longitudinal maneuver. The reduction of the incremental wing bending moment due to maneuvers can lead to benefits such as improved pay-loads/gross weight capabilities and/or extended structural fatigue life. The maneuver is performed by following a desired vertical load factor law with elevators deflections, starting from the trim equilibrium in level flight. The system observes load factor and structural bending through accelerometers and calibrated strain sensors and then sends signals to a computer that symmetrically actuates ailerons for reducing the structural bending and elevators for compensating the perturbation to the longitudinal equilibrium. The major limit of this kind of systems appears when it has to be installed on commercial transport aircraft for reduced OEW or augmented wing aspect-ratio. In this case extensive RAMS analyses and high redundancy of the MLC related sub-systems are required by the Certification Authority. Otherwise the structural design must be performed at system off. Thus the unique actual benefit to be gained from the adoption of a MLC system on a commercial transport is the fatigue life extension. An application to a business aircraft responding to the EASA Certification Specifications, Part 25, has been performed. The aircraft used for the numerical application is considered only as a test case-study. Most of design and analysis considerations are applicable also to other aircraft, such as unmanned or military ones, although some design requirements can be clearly different. The estimation of the fatigue life extension of a structural joint (wing lower skin-stringer, located close to the wing root, has been estimated by showing

  9. Femoral head avascular necrosis

    International Nuclear Information System (INIS)

    Chrysikopoulos, H.; Sartoris, D.J.; Resnick, D.L.; Ashburn, W.; Pretorius, T.

    1988-01-01

    MR imaging has been shown to be more sensitive and specific than planar scintigraphy for avascular necrosis (AVN) of the femoral head. However, experience with single photon emission CT (SPECT) is limited. The authors retrospectively compared 1.5-T MR imaging with SPECT in 14 patients with suspected femoral head AVN. Agreement between MR imaging and SPECT was present in 24 femurs, 14 normal and ten with AVN. MR imaging showed changes of AVN in the remaining four femoral heads. Of these, one was normal and the other three inconclusive for AVN by SPECT. The authors conclude that MR imaging is superior to SPECT for the evaluation of AVN of the hip

  10. Protective head of sensors

    International Nuclear Information System (INIS)

    Liska, K.; Anton, P.

    1987-01-01

    The discovery concerns the protective heads of diagnostic assemblies of nuclear power plants for conductors of the sensors from the fuel and control parts of the said assemblies. A detailed description is presented of the design of the protective head which, as compared with the previous design, allows quick and simple assembly with reduced risk of damaging the sensors. The protective head may be used for diagnostic assemblies both in power and in research reactors and it will be used for WWER reactor assemblies. (A.K.). 3 figs

  11. Adaptive Injection-locking Oscillator Array for RF Spectrum Analysis

    International Nuclear Information System (INIS)

    Leung, Daniel

    2011-01-01

    A highly parallel radio frequency receiver using an array of injection-locking oscillators for on-chip, rapid estimation of signal amplitudes and frequencies is considered. The oscillators are tuned to different natural frequencies, and variable gain amplifiers are used to provide negative feedback to adapt the locking band-width with the input signal to yield a combined measure of input signal amplitude and frequency detuning. To further this effort, an array of 16 two-stage differential ring oscillators and 16 Gilbert-cell mixers is designed for 40-400 MHz operation. The injection-locking oscillator array is assembled on a custom printed-circuit board. Control and calibration is achieved by on-board microcontroller.

  12. Restitution in the context of institutional lock-in

    Directory of Open Access Journals (Sweden)

    Załęczna Magdalena

    2014-01-01

    Full Text Available This article presents the problem of lack of restitution in Poland in the political, social and economic context. The author presents the theory of institutional lock-in, referring to the hitherto course of the political, social and economic transformation processes in Poland. She is focusing on the research problem in form of an institutional lock-in on the route to general restitution process. The author examines the path shaping and path dependence to understand the current negative attitude toward restitution presented by the government and society. The author also indicates the costs caused by lack of restitution. Through analysis of past attempts of restitution regulations the author indicates the most important flashpoints. A hypothesis constructed by the author focuses on the negative effects of institutional lock-in, lack of restitution increases transaction costs influencing the Polish economy. The study is based on the legal documents and the results of public opinion polls.

  13. Beating quantum limits in interferometers with quantum locking of mirrors

    International Nuclear Information System (INIS)

    Heidmann, Antoine; Courty, Jean-Michel; Pinard, Michel; Lebars, Julien

    2004-01-01

    The sensitivity in interferometric measurements such as those made by gravitational-wave detectors is ultimately limited by the quantum noise of light. We discuss the use of feedback mechanisms to reduce the quantum effects of radiation pressure. Recent experiments have shown that it is possible to reduce the thermal motion of a mirror by cold damping. The mirror motion is measured with an optomechanical sensor based on a high-finesse cavity, and reduced by a feedback loop. We show that this technique can be extended to lock the mirror at the quantum level. In gravitational-wave interferometers with Fabry-Perot cavities in each arm, it is even possible to use a single feedback mechanism to lock one cavity mirror on the other. This quantum locking greatly improves the sensitivity of the interferometric measurement. It is furthermore insensitive to imperfections such as losses in the interferometer

  14. Injection Locking of a Semiconductor Double Quantum Dot Micromaser.

    Science.gov (United States)

    Liu, Y-Y; Stehlik, J; Gullans, M J; Taylor, J M; Petta, J R

    2015-11-01

    Emission linewidth is an important figure of merit for masers and lasers. We recently demonstrated a semiconductor double quantum dot (DQD) micromaser where photons are generated through single electron tunneling events. Charge noise directly couples to the DQD energy levels, resulting in a maser linewidth that is more than 100 times larger than the Schawlow-Townes prediction. Here we demonstrate a linewidth narrowing of more than a factor 10 by locking the DQD emission to a coherent tone that is injected to the input port of the cavity. We measure the injection locking range as a function of cavity input power and show that it is in agreement with the Adler equation. The position and amplitude of distortion sidebands that appear outside of the injection locking range are quantitatively examined. Our results show that this unconventional maser, which is impacted by strong charge noise and electron-phonon coupling, is well described by standard laser models.

  15. Stability improvement for coil position locking of joule balance

    Science.gov (United States)

    Bai, Yang; Liu, Yongmeng; Lu, Yunfeng; Hu, Pengcheng; Wang, Dawei; Li, Zhengkun; Tan, Jiubin; Zhang, Zhonghua

    2017-08-01

    The relative vertical position locking precision between the exciting and suspended coils is an important uncertainty for the Planck constant traceability in joule balance. In order to improve the relative vertical position locking precision, several stability experiments are conducted. The stability characteristics of the suspended and exciting coils are measured using a six-axis laser interferometer system; meanwhile, the effectiveness of the active vibration isolation table is measured using a vibration measurement sensor. The piezoelectric ceramic actuators with PID controller are used to compensate the relative vertical displacement drifts while a six-axis laser interferometer system is used to measure the positions of two coils. Experimental results show that the relative vertical position is stably locked.

  16. Magnetized color flavor locked state and compact stars

    CERN Document Server

    Felipe, R Gonzalez; Martinez, A Perez

    2010-01-01

    The stability of the color flavor locked phase in the presence of a strong magnetic field is investigated within the phenomenological MIT bag model, taking into account the variation of the strange quark mass, the baryon density, the magnetic field, as well as the bag and gap parameters. It is found that the minimum value of the energy per baryon in a color flavor locked state at vanishing pressure is lower than the corresponding one for unpaired magnetized strange quark matter and, as the magnetic field increases, the energy per baryon decreases. This implies that magnetized color flavor locked matter is more stable and could become the ground state inside neutron stars. The mass-radius relation for such stars is also studied.

  17. Wavenumber locking and pattern formation in spatially forced systems

    International Nuclear Information System (INIS)

    Manor, Rotem; Meron, Ehud; Hagberg, Aric

    2009-01-01

    We study wavenumber locking and pattern formation resulting from weak spatially periodic one-dimensional forcing of two-dimensional systems. We consider systems that produce stationary or traveling stripe patterns when unforced and apply forcing aligned with the stripes. Forcing at close to twice the pattern wavenumber selects, stabilizes, or creates resonant stripes locked at half the forcing wavenumber. If the mismatch between the forcing and pattern wavenumber is high we find that the pattern still locks but develops a wave vector component perpendicular to the forcing direction and forms rectangular and oblique patterns. When the unforced system supports traveling waves, resonant rectangular patterns remain stationary but oblique patterns travel in a direction orthogonal to the traveling waves.

  18. 75 FR 5071 - Mississippi L&D 21, LLC, Mississippi River No. 21 Hydropower Company Lock + TM

    Science.gov (United States)

    2010-02-01

    ... Lock + \\TM\\ Hydro Friends Fund XXXII, LLC; Notice of Preliminary Permit Applications Accepted for..., Lock + TM Hydro Friends Fund XXXII, LLC (Lock + Hydro) filed an application for a preliminary permit...

  19. Phase-locked flux-flow Josephson oscillator

    DEFF Research Database (Denmark)

    Ustinov, A. V.; Mygind, Jesper; Oboznov, V. A.

    1992-01-01

    We report on the observation of large rf induced steps due to phase-locking of unidirectional flux-flow motion in long quasi-one-dimensional Josephson junctions. The external microwave irradiation in the frequency range 62–77 GHz was applied from the edge of the junction at which the fluxons enter....... The dependence of the amplitude of the phase-locked step on external magnetic field and microwave power has been measured. The observed zero-crossing steps have potential application in Josephson voltage standards. A simple model for the flux-flow as determined by the microwave driven boundary gate at the edge...

  20. Cyclotomy and Ramanujan sums in quantum phase locking

    International Nuclear Information System (INIS)

    Planat, Michel; Rosu, Haret C.

    2003-01-01

    Phase-locking governs the phase noise in classical clocks through effects described in precise mathematical terms. We seek here a quantum counterpart of these effects by working in a finite Hilbert space. We use a coprimality condition to define phase-locked quantum states and the corresponding Pegg-Barnett type phase operator. Cyclotomic symmetries in matrix elements are revealed and related to Ramanujan sums in the theory of prime numbers. The employed mathematical procedures also emphasize the isomorphism between algebraic number theory and the theory of quantum entanglement

  1. Positioning and locking device for fuel pin to grid attachment

    International Nuclear Information System (INIS)

    Frick, T.M.; Wineman, A.L.

    1976-01-01

    A positioning and locking device for fuel pin to grid attachment provides an inexpensive means of positively positioning and locking the individual fuel pins which make up the driver fuel assemblies used in nuclear reactors. The device can be adapted for use with a currently used attachment grid assembly design and insures that the pins remain in their proper position throughout the in-reactor life of the assembly. This device also simplifies fuel bundle assembly in that a complete row of fuel pins can be added to the bundle during each step of assembly. 8 claims, 8 drawing figures

  2. Inter-comb synchronization by mode-to-mode locking

    Science.gov (United States)

    Chun, Byung Jae; Kim, Young-Jin; Kim, Seung-Woo

    2016-08-01

    Two combs of fiber femtosecond lasers are synchronized through the optical frequency reference created by injection-locking of a diode laser to a single comb mode. Maintaining a mHz-level narrow linewidth, the optical frequency reference permits two combs to be stabilized by mode-to-mode locking with a relative stability of 1.52  ×  10-16 at 10 s with a frequency slip of 2.46 mHz. This inter-comb synchronization can be utilized for applications such as dual-comb spectroscopy or ultra-short pulse synthesis without extra narrow-linewidth lasers.

  3. Microwave phase locking of Josephson-junction fluxon oscillators

    DEFF Research Database (Denmark)

    Salerno, M.; Samuelsen, Mogens Rugholm; Filatrella, G.

    1990-01-01

    Application of the classic McLaughlin-Scott soliton perturbation theory to a Josephson-junction fluxon subjected to a microwave field that interacts with the fluxon only at the junction boundaries reduces the problem of phase locking of the fluxon oscillation to the study of a two-dimensional fun......Application of the classic McLaughlin-Scott soliton perturbation theory to a Josephson-junction fluxon subjected to a microwave field that interacts with the fluxon only at the junction boundaries reduces the problem of phase locking of the fluxon oscillation to the study of a two...

  4. Lock-in imaging with synchronous digital mirror demodulation

    Science.gov (United States)

    Bush, Michael G.

    2010-04-01

    Lock-in imaging enables high contrast imaging in adverse conditions by exploiting a modulated light source and homodyne detection. We report results on a patent pending lock-in imaging system fabricated from commercial-off-theshelf parts utilizing standard cameras and a spatial light modulator. By leveraging the capabilities of standard parts we are able to present a low cost, high resolution, high sensitivity camera with applications in search and rescue, friend or foe identification (IFF), and covert surveillance. Different operating modes allow the same instrument to be utilized for dual band multispectral imaging or high dynamic range imaging, increasing the flexibility in different operational settings.

  5. Pre-Extreme Automotive Anti-Lock Brake Systems

    Directory of Open Access Journals (Sweden)

    V. G. Ivanov

    2004-01-01

    Full Text Available Designing of systems ensuring active safety of automobiles with intellectual functions requires usage of new control principles for wheel and automobile operation. One of such principles is a preextreme control strategy. Its aim is to ensure wheel work in pre-extreme, stable area of «tire grip coefficient wheel slip coefficient» dependence. The simplest realization of pre-extreme control in automotive anti-lock brake systems consists in the threshold and gradient algorithms. A comparative analysis of these algorithms which has been made on simulation results of bus braking with various anti-lock brake systems has revealed their high efficiency.

  6. Relaxation towards phase-locked dynamics in long Josephson junctions

    DEFF Research Database (Denmark)

    Salerno, M.; Grønbech-Jensen, Niels; Samuelsen, Mogens Rugholm

    1995-01-01

    We study the relaxation phenomenon towards phase-locked dynamics in long Josephson junctions. In particular the dependence of the relaxation frequency for the equal time of flight solution on the junction parameters is derived. The analysis is based on a phase-locked map and is compared with direct...... numerical experiments performed both on the map and on the perturbed sine-Gordon equation. As an interesting result we find that very close to a bifurcation the relaxation frequency is exactly equal to the half of the step frequency, i.e., the frequency characterizing the period-one solution....

  7. Head injury causation scenarios for belted, rear-seated children in frontal impacts.

    Science.gov (United States)

    Bohman, Katarina; Arbogast, Kristy B; Bostrom, Ola

    2011-02-01

    Head injuries are the most common serious injuries sustained by children in motor vehicle crashes and are of critical importance with regard to long-term disability. There is a lack of understanding of how seat belt-restrained children sustain head injuries in frontal impacts. The aim of the study was to identify the AIS2+ head injury causation scenarios for rear-seated, belt-restrained children in frontal impacts, including the set of parameters contributing to the injury. In-depth crash investigations from two National Highway Traffic Safety Administration (NHTSA) databases, the National Automotive Sampling System-Crashworthiness Data System (NASS-CDS; 1997-2008) and the Crash Injury Research and Engineering Network (CIREN; 1996-2009), were collected and analyzed in detail. Selection criteria were all frontal impacts with principal direction of force (PDOF) of 11, 12, and 1 o'clock involving rear-seated, three-point belt-restrained, with or without booster cushion, children from 3 to 13 years with an AIS2+ head injury. Cases were analyzed using the BioTab method of injury causation assessment in order to systematically analyze the injury causation scenario for each case. There were 27 cases meeting the inclusion criteria, 19 cases with MAIS2 head injuries and 8 cases with MAIS3+ head injuries, including 2 fatalities. Three major injury causation scenarios were identified, including head contact with seatback (10 cases), head contact with side interior (7 cases,) and no evidence of head contact (9 cases). Head injuries with seatback or side interior contact typically included a PDOF greater than 10 degree (similar to the Insurance Institute for Highway Safety [IIHS] and EuroNCAP offset frontal testing) and vehicle maneuvers. For seatback contact, the vehicle's movements contributed to occupant kinematics inboard the vehicle, causing a less than optimal restraint of the torso and/or torso roll out of the shoulder belt. For side interior contact, the PDOF and

  8. Computed Tomography (CT) -- Head

    Medline Plus

    Full Text Available ... you! Do you have a personal story about radiology? Share your patient story here Images × Image Gallery ... Pregnancy Head and Neck Cancer X-ray, Interventional Radiology and Nuclear Medicine Radiation Safety Images related to ...

  9. Exploding head syndrome.

    Science.gov (United States)

    Sharpless, Brian A

    2014-12-01

    Exploding head syndrome is characterized by the perception of abrupt, loud noises when going to sleep or waking up. They are usually painless, but associated with fear and distress. In spite of the fact that its characteristic symptomatology was first described approximately 150 y ago, exploding head syndrome has received relatively little empirical and clinical attention. Therefore, a comprehensive review of the scientific literature using Medline, PsycINFO, Google Scholar, and PubMed was undertaken. After first discussing the history, prevalence, and associated features, the available polysomnography data and five main etiological theories for exploding head syndrome are summarized. None of these theories has yet reached dominance in the field. Next, the various methods used to assess and treat exploding head syndrome are discussed, as well as the limited outcome data. Finally, recommendations for future measure construction, treatment options, and differential diagnosis are provided. Copyright © 2014 Elsevier Ltd. All rights reserved.

  10. Computed Tomography (CT) -- Head

    Medline Plus

    Full Text Available ... medically necessary because of potential risk to the baby. This risk is, however, minimal with head CT ... intravenous contrast indicate mothers should not breastfeed their babies for 24-48 hours after contrast medium is ...

  11. Early Head Start Evaluation

    Data.gov (United States)

    U.S. Department of Health & Human Services — Longitudinal information from an evaluation where children were randomly assigned to Early Head Start or community services as usual;direct assessments and...

  12. Computed Tomography (CT) -- Head

    Medline Plus

    Full Text Available ... top of page Additional Information and Resources RTAnswers.org Radiation Therapy for Brain Tumors Radiation Therapy for ... Tomography (CT) - Head Sponsored by Please note RadiologyInfo.org is not a medical facility. Please contact your ...

  13. Computed Tomography (CT) -- Head

    Medline Plus

    Full Text Available ... of the Head? Computed tomography, more commonly known as a CT or CAT scan, is a diagnostic ... white on the x-ray; soft tissue, such as organs like the heart or liver, shows up ...

  14. Computed Tomography (CT) -- Head

    Medline Plus

    Full Text Available ... microphone. top of page How does the procedure work? In many ways CT scanning works very much ... head CT scanning. Manufacturers of intravenous contrast indicate mothers should not breastfeed their babies for 24-48 ...

  15. Computed Tomography (CT) -- Head

    Medline Plus

    Full Text Available ... rays). top of page What are some common uses of the procedure? CT scanning of the head ... is done because a potential abnormality needs further evaluation with additional views or a special imaging technique. ...

  16. Computed Tomography (CT) -- Head

    Medline Plus

    Full Text Available ... rays). top of page What are some common uses of the procedure? CT scanning of the head ... community, you can search the ACR-accredited facilities database . This website does not provide cost information. The ...

  17. Head Start Impact Study

    Data.gov (United States)

    U.S. Department of Health & Human Services — Nationally representative, longitudinal information from an evaluation where children were randomly assigned to Head Start or community services as usual;direct...

  18. Computed Tomography (CT) -- Head

    Medline Plus

    Full Text Available ... Stroke Brain Tumors Computer Tomography (CT) Safety During Pregnancy Head and Neck Cancer X-ray, Interventional Radiology and Nuclear Medicine Radiation Safety Images related to Computed Tomography (CT) - ...

  19. TCGA head Neck

    Science.gov (United States)

    Investigators with The Cancer Genome Atlas (TCGA) Research Network have discovered genomic differences – with potentially important clinical implications – in head and neck cancers caused by infection with the human papillomavirus (HPV).

  20. Computed Tomography (CT) -- Head

    Medline Plus

    Full Text Available ... your doctor to evaluate your face, sinuses, and skull or to plan radiation therapy for brain cancer. ... typically used to detect: bleeding, brain injury and skull fractures in patients with head injuries. bleeding caused ...

  1. The exploding head syndrome.

    Science.gov (United States)

    Green, M W

    2001-06-01

    This article reviews the features of an uncommon malady termed "the exploding head syndrome." Sufferers describe terrorizing attacks of a painless explosion within their head. Attacks tend to occur at the onset of sleep. The etiology of attacks is unknown, although they are considered to be benign. Treatment with clomipramine has been suggested, although most sufferers require only reassurance that the spells are benign in nature.

  2. The Pringle maneuver reduces the infusion rate of rocuronium required to maintain surgical muscle relaxation during hepatectomy.

    Science.gov (United States)

    Kajiura, Akira; Nagata, Osamu; Sanui, Masamitsu

    2018-04-27

    We investigated the continuous infusion rates of rocuronium necessary to obtain the surgical muscle relaxation before, during, and after the Pringle maneuver on patients who underwent hepatectomy. Fifteen patients were induced by total intravenous anesthesia with propofol. After obtaining the calibration of acceleromyography, the patient was intubated with rocuronium 0.6 mg/kg. Fifteen minutes after initial rocuronium injection, the continuous infusion was started at 7.5 µg/kg/min. The infusion rate was adjusted every 15 min so that the first twitch height (% T1) might become from 3 to 10% of control. The infusion rates at the time when the state of surgical muscle relaxation was achieved for more than 15 min were recorded before, during and after the Pringle maneuver. The 25% recovery time was measured after discontinuing the continuous infusion. The infusion rate of rocuronium before, during, and after the Pringle maneuver was 7.2 ± 1.8, 4.2 ± 1.4, and 4.7 ± 1.5 µg/kg/min (mean ± SD), respectively. The rocuronium infusion rate during the Pringle maneuver was decreased about 40% compared to that before this maneuver, and that after completion of the Pringle maneuver was not recovered to that before the Pringle maneuver. The 25% recovery time was 20 ± 7 min. In case of continuous administration of rocuronium during surgery performing the Pringle maneuver, it was considered necessary to regulate the administration of rocuronium using muscle relaxant monitoring in order to deal with the decrease in muscle relaxant requirement by the Pringle maneuver.

  3. GPK heading machine

    Energy Technology Data Exchange (ETDEWEB)

    Krmasek, J.; Novosad, K.

    1981-01-01

    This article evaluates performance tests of the Soviet made GPK heading machine carried out in 4 coal mines in Czechoslovakia (Ostrava-Karvina region and Kladno mines). GPK works in coal seams and rocks with compression strength of 40 to 50 MPa. Dimensions of the tunnel are height 1.8 to 3.8 m and width 2.6 to 4.7 m, tunnel gradient plus to minus 10 degrees. GPK weighs 16 t, its conical shaped cutting head equipped with RKS-1 cutting tools is driven by an electric motor with 55 kW capacity. Undercarriage of the GPK, gathering-arm loader, hydraulic system, electric system and dust supression system (water spraying or pneumatic section) are characterized. Specifications of GPK heading machines are compared with PK-3r and F8 heading machines. Reliability, number of failures, dust level, noise, productivity depending on compression strength of rocks, heading rate in coal and in rocks, energy consumption, performance in inclined tunnels, and cutting tool wear are evaluated. Tests show that GPK can be used to drive tunnels in coal with rock constituting up to 50% of the tunnel crosscut, as long as rock compression strength does not exceed 50 MPa. In rocks characterized by higher compression strength cutting tool wear sharply increases. GPK is characterized by higher productivity than that of the PK-3r heading machine. Among the weak points of the GPK are: unsatisfactory reliability and excessive wear of its elements. (4 refs.) (In Czech)

  4. Taurolidine lock is superior to heparin lock in the prevention of catheter related bloodstream infections and occlusions.

    Directory of Open Access Journals (Sweden)

    Evelyn D Olthof

    Full Text Available Patients on home parenteral nutrition (HPN are at risk for catheter-related complications; mainly infections and occlusions. We have previously shown in HPN patients presenting with catheter sepsis that catheter locking with taurolidine dramatically reduced re-infections when compared with heparin. Our HPN population therefore switched from heparin to taurolidine in 2008. The aim of the present study was to compare long-term effects of this catheter lock strategy on the occurrence of catheter-related bloodstream infections and occlusions in HPN patients.Data of catheter-related complications were retrospectively collected from 212 patients who received HPN between January 2000 and November 2011, comprising 545 and 200 catheters during catheter lock therapy with heparin and taurolidine, respectively. We evaluated catheter-related bloodstream infection and occlusion incidence rates using Poisson-normal regression analysis. Incidence rate ratios were calculated by dividing incidence rates of heparin by those of taurolidine, adjusting for underlying disease, use of anticoagulants or immune suppressives, frequency of HPN/fluid administration, composition of infusion fluids, and duration of HPN/fluid use before catheter creation.Bloodstream infection incidence rates were 1.1/year for heparin and 0.2/year for taurolidine locked catheters. Occlusion incidence rates were 0.2/year for heparin and 0.1/year for taurolidine locked catheters. Adjusted incidence ratios of heparin compared to taurolidine were 5.9 (95% confidence interval, 3.9-8.7 for bloodstream infections and 1.9 (95% confidence interval, 1.1-3.1 for occlusions.Given that no other procedural changes than the catheter lock strategy were implemented during the observation period, these data strongly suggest that taurolidine decreases catheter-related bloodstream infections and occlusions in HPN patients compared with heparin.

  5. Neural Network Prediction of Disruptions Caused by Locked Modes on J-TEXT Tokamak

    International Nuclear Information System (INIS)

    Ding Yonghua; Jin Xuesong; Chen Zhenzhen; Zhuang Ge

    2013-01-01

    Prediction of disruptions caused by locked modes using the Back-Propagation (BP) neural network is completed on J-TEXT tokamak. The network, which is based on the BP neural network, uses Mirnov coils and locked mode coils signals as input data, and outputs a signal including information of prediction of locked mode. The rate of successful prediction of locked modes is more than 90%. For intrinsic locked mode disruptions, the network can give a prewarning signal about 1 ms ahead of the locking-time. For the disruption caused by resonant magnetic perturbation (RMPs) locked modes, the network can give a prewarning signal about 10 ms ahead of the locking-time

  6. On the mechanisms governing the repetition rate of mode-locked semiconductor lasers

    DEFF Research Database (Denmark)

    Mulet, Josep; Mørk, Jesper

    2004-01-01

    We investigate the mechanisms influencing the synchronization locking range of mode-locked lasers. We find that changes in repetition rates can be accomodated through a joint interplay of dispersion and pulse shaping effects....

  7. Mode-locking dynamics in a quantum-dash Fabry-Pérot laser diode for packet based clock recovery applications

    NARCIS (Netherlands)

    Maldonado-Basilio, R.; Parra-Cetina, J.; Latkowski, S.; Landais, P.; Calabretta, N.

    2012-01-01

    We experimentally investigate the locking/unlocking dynamics of a mode-locked QDash laser diode for packet-based clock-recovery applications. Results show 20 ns locking times for the passively and externally synchronized mode-locking mechanisms.

  8. Evaluation of lung recruitment maneuvers in acute respiratory distress syndrome using computer simulation.

    Science.gov (United States)

    Das, Anup; Cole, Oana; Chikhani, Marc; Wang, Wenfei; Ali, Tayyba; Haque, Mainul; Bates, Declan G; Hardman, Jonathan G

    2015-01-12

    Direct comparison of the relative efficacy of different recruitment maneuvers (RMs) for patients with acute respiratory distress syndrome (ARDS) via clinical trials is difficult, due to the heterogeneity of patient populations and disease states, as well as a variety of practical issues. There is also significant uncertainty regarding the minimum values of positive end-expiratory pressure (PEEP) required to ensure maintenance of effective lung recruitment using RMs. We used patient-specific computational simulation to analyze how three different RMs act to improve physiological responses, and investigate how different levels of PEEP contribute to maintaining effective lung recruitment. We conducted experiments on five 'virtual' ARDS patients using a computational simulator that reproduces static and dynamic features of a multivariable clinical dataset on the responses of individual ARDS patients to a range of ventilator inputs. Three recruitment maneuvers (sustained inflation (SI), maximal recruitment strategy (MRS) followed by a titrated PEEP, and prolonged recruitment maneuver (PRM)) were implemented and evaluated for a range of different pressure settings. All maneuvers demonstrated improvements in gas exchange, but the extent and duration of improvement varied significantly, as did the observed mechanism of operation. Maintaining adequate post-RM levels of PEEP was seen to be crucial in avoiding cliff-edge type re-collapse of alveolar units for all maneuvers. For all five patients, the MRS exhibited the most prolonged improvement in oxygenation, and we found that a PEEP setting of 35 cm H2O with a fixed driving pressure of 15 cm H2O (above PEEP) was sufficient to achieve 95% recruitment. Subsequently, we found that PEEP titrated to a value of 16 cm H2O was able to maintain 95% recruitment in all five patients. There appears to be significant scope for reducing the peak levels of PEEP originally specified in the MRS and hence to avoid exposing the lung to

  9. Integrated detection, estimation, and guidance in pursuit of a maneuvering target

    Science.gov (United States)

    Dionne, Dany

    The thesis focuses on efficient solutions of non-cooperative pursuit-evasion games with imperfect information on the state of the system. This problem is important in the context of interception of future maneuverable ballistic missiles. However, the theoretical developments are expected to find application to a broad class of hybrid control and estimation problems in industry. The validity of the results is nevertheless confirmed using a benchmark problem in the area of terminal guidance. A specific interception scenario between an incoming target with no information and a single interceptor missile with noisy measurements is analyzed in the form of a linear hybrid system subject to additive abrupt changes. The general research is aimed to achieve improved homing accuracy by integrating ideas from detection theory, state estimation theory and guidance. The results achieved can be summarized as follows. (i) Two novel maneuver detectors are developed to diagnose abrupt changes in a class of hybrid systems (detection and isolation of evasive maneuvers): a new implementation of the GLR detector and the novel adaptive- H0 GLR detector. (ii) Two novel state estimators for target tracking are derived using the novel maneuver detectors. The state estimators employ parameterized family of functions to described possible evasive maneuvers. (iii) A novel adaptive Bayesian multiple model predictor of the ballistic miss is developed which employs semi-Markov models and ideas from detection theory. (iv) A novel integrated estimation and guidance scheme that significantly improves the homing accuracy is also presented. The integrated scheme employs banks of estimators and guidance laws, a maneuver detector, and an on-line governor; the scheme is adaptive with respect to the uncertainty affecting the probability density function of the filtered state. (v) A novel discretization technique for the family of continuous-time, game theoretic, bang-bang guidance laws is introduced. The

  10. Early Mission Maneuver Operations for the Deep Space Climate Observatory Sun-Earth L1 Libration Point Mission

    Science.gov (United States)

    Roberts, Craig; Case, Sara; Reagoso, John; Webster, Cassandra

    2015-01-01

    The Deep Space Climate Observatory mission launched on February 11, 2015, and inserted onto a transfer trajectory toward a Lissajous orbit around the Sun-Earth L1 libration point. This paper presents an overview of the baseline transfer orbit and early mission maneuver operations leading up to the start of nominal science orbit operations. In particular, the analysis and performance of the spacecraft insertion, mid-course correction maneuvers, and the deep-space Lissajous orbit insertion maneuvers are discussed, com-paring the baseline orbit with actual mission results and highlighting mission and operations constraints..

  11. A multinomial-logit ordered-probit model for jointly analyzing crash avoidance maneuvers and crash severity

    DEFF Research Database (Denmark)

    Kaplan, Sigal; Prato, Carlo Giacomo

    ' propensity to engage in various corrective maneuvers in the case of the critical event of vehicle travelling. Five lateral and speed control maneuvers are considered: “braking”, “steering”, “braking & steering”, and “other maneuvers”, in addition to a “no action” option. The analyzed data are retrieved from...... the United States National Automotive Sampling System General Estimates System (GES) crash database for the years 2005-2009. Results show (i) the correlation between crash avoidance maneuvers and crash severity, and (ii) the link between drivers' attributes, risky driving behavior, road characteristics...

  12. Mode locking of Yb:GdYAG ceramic lasers with an isotropic cavity

    International Nuclear Information System (INIS)

    Xu, C W; Tang, D Y; Zhu, H Y; Zhang, J

    2013-01-01

    We report on the passive mode locking of a diode pumped Yb:GdYAG ceramic laser with a near isotropic cavity. It is found that the laser could simultaneously mode lock in the two orthogonal principal polarization directions of the cavity, and the mode locked pulses of the two polarizations have identical features and are temporally perfectly synchronized. However, their pulse energy varies out-of-phase periodically, manifesting the antiphase dynamics of mode locked lasers. (letter)

  13. Remote Core Locking: Migrating Critical-Section Execution to Improve the Performance of Multithreaded Applications

    OpenAIRE

    Lozi , Jean-Pierre; David , Florian; Thomas , Gaël; Lawall , Julia; Muller , Gilles

    2014-01-01

    National audience; The scalability of multithreaded applications on current multicore systems is hampered by the performance of lock algorithms, due to the costs of access contention and cache misses. In this paper, we propose a new lock algorithm, Remote Core Locking (RCL), that aims to improve the performance of critical sections in legacy applications on multicore architectures. The idea of RCL is to replace lock acquisitions by optimized remote procedure calls to a dedicated server core. ...

  14. Phase-locked loops. [in analog and digital circuits communication system

    Science.gov (United States)

    Gupta, S. C.

    1975-01-01

    An attempt to systematically outline the work done in the area of phase-locked loops which are now used in modern communication system design is presented. The analog phase-locked loops are well documented in several books but discrete, analog-digital, and digital phase-locked loop work is scattered. Apart from discussing the various analysis, design, and application aspects of phase-locked loops, a number of references are given in the bibliography.

  15. Intramedullary fixation of proximal humerus fractures: do locking bolts endanger the axillary nerve or the ascending branch of the anterior circumflex artery? A cadaveric study

    Directory of Open Access Journals (Sweden)

    Sermon An

    2008-12-01

    Full Text Available Abstract Background Proximal humerus fractures are one of the most common fractures. Intramedullary locked nailing is becoming a popular alternative treatment, especially for easier fracture patterns. Although axillary nerve injury has been reported, no study has compared the safety of the proximal locking options relative to the axillary nerve and the ascending branch of the anterior circumflex artery. Method Six different commercially available proximal humeral nails were implanted in 30 shoulders of 18 cadavers. After fluoroscopically guided implantation the shoulders were carefully dissected and the distance between the locking screws, the axillary nerve and the ascending branch of the anterior circumflex artery was measured. Results The course of the axillary nerve varies. A mean distance of 55.8 mm (SD = 5.3 between the lateral edge of the acromions and the axillary nerve at the middle of the humerus in a neutrally rotated position was observed. The minimum distance was 43.4 mm, the maximum 63.9 mm. Bent nails with oblique head interlocking bolts appeared to be the most dangerous in relation to the axillary nerve. The two designs featuring such a bend and oblique bolt showed a mean distance of the locking screw to the axillary nerve of 1 mm and 2.7 mm respectively Sirus (Zimmer® and (Stryker® T2 PHN (Proximal Humeral Nail. Regarding the ascending branch of the anterior circumflex artery, there was no difference between the nails which have an anteroposterior locking option. Conclusion It is of great importance for surgeons treating proximal humerus fractures to understand the relative risk of any procedure they perform. Since the designs of different nailing systems risk damaging the axillary nerve and ascending branch, blunt dissection, the use of protection sleeves during drilling and screw insertion, and individual risk evaluation prior to the use of a proximal humeral nail are advocated.

  16. Magnetic Resonance Imaging (MRI) -- Head

    Science.gov (United States)

    ... News Physician Resources Professions Site Index A-Z Magnetic Resonance Imaging (MRI) - Head Magnetic resonance imaging (MRI) of the head uses a powerful ... the Head? What is MRI of the Head? Magnetic resonance imaging (MRI) is a noninvasive medical test that ...

  17. Magnetic Resonance Imaging (MRI) -- Head

    Medline Plus

    Full Text Available ... News Physician Resources Professions Site Index A-Z Magnetic Resonance Imaging (MRI) - Head Magnetic resonance imaging (MRI) of the head uses a powerful ... the Head? What is MRI of the Head? Magnetic resonance imaging (MRI) is a noninvasive medical test that ...

  18. Head, Neck, and Oral Cancer

    Medline Plus

    Full Text Available ... find out more. Oral, Head and Neck Pathology Oral, Head and Neck Pathology Close to 49,750 Americans will be diagnosed ... find out more. Oral, Head and Neck Pathology Oral, Head and Neck Pathology Close to 49,750 Americans will be diagnosed ...

  19. Head, Neck, and Oral Cancer

    Science.gov (United States)

    ... find out more. Oral, Head and Neck Pathology Oral, Head and Neck Pathology Close to 49,750 Americans will be diagnosed ... find out more. Oral, Head and Neck Pathology Oral, Head and Neck Pathology Close to 49,750 Americans will be diagnosed ...

  20. New fixation method for maxillary distraction osteogenesis using locking attachments.

    Science.gov (United States)

    Suzuki, Eduardo Yugo; Buranastidporn, Boonsiva; Ishii, Masatoshi

    2006-10-01

    The external traction hooks of the intraoral splint used in the rigid external distraction (RED) system for maxillary distraction osteogenesis interfere with the surgical procedures. The purpose of this study is to introduce an innovative splint fixation method for maxillary distraction osteogenesis with Locking Attachments and evaluate their advantages, such as reduction of operating time compared with the traditional intraoral splint method. Retrospective comparison of operative times of maxillary Le Fort I osteotomy procedures was carried out with the traditional protocol using the intraoral splint cemented to the maxillary dentition (n = 14), and a removable intraoral splint that is inserted postsurgically (n = 14). Operative procedure times were compared and analyzed statistically using the data extracted from the surgical records. There were no complications inserting the removable splint postsurgically, including pain, discomfort, or time-consuming procedure. Stable and secure splint fixation was obtained before the distraction procedure and the desired treatment goals were obtained in all patients. The total operative procedure times were significantly reduced in the Locking Attachments group by 24% to 41% (approximately 65 minutes) compared with earlier operations involving the conventional splints (P Maxillary distraction osteogenesis with the Locking Attachments is a highly effective fixation approach to manage severe hypoplastic maxilla, eliminating lip constraints resulting from scarring and allowing for easier, more deliberate and careful dissection. The use of the Locking Attachments is reliable in craniofacial surgery and has proved to be advantageous in the reduction of the operating time and surgical risks.