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Sample records for fundal pressure maneuver

  1. Effect of jaw thrust and cricoid pressure maneuvers on glottic visualization during GlideScope videolaryngoscopy.

    Science.gov (United States)

    Corda, David M; Riutort, Kevin T; Leone, Alex J; Qureshi, Mueez K; Heckman, Michael G; Brull, Sorin J

    2012-06-01

    During performance of direct laryngoscopy in the difficult-to-visualize airway, several maneuvers have the potential to impact glottic visualization, including jaw thrust and cricoid pressure. The effect of these maneuvers on glottic visualization during videolaryngoscopy has not been studied. We evaluated the effect of jaw thrust and cricoid pressure maneuvers on both visualization of the glottis and the area of glottic opening visible during GlideScope-aided videolaryngoscopy. One hundred patients were enrolled in this study. After induction of general anesthesia, videolaryngoscopy was followed by jaw thrust and cricoid pressure maneuvers performed in random order. Laryngeal anatomy was recorded continuously and was saved as digital images following the initial laryngoscopy and after each maneuver. Glottis grade [modified Cormack and Lehane (C&L)] was recorded, as was the total glottic area. There was improvement in glottis grade when utilizing jaw thrust maneuver in comparison to GlideScope videolaryngoscopy alone (31% improved, 4% worsened; P thrust maneuver in comparison with videolaryngoscopy alone (P thrust maneuver was superior to videolaryngoscopy alone in improving the modified C&L grade and the visualized glottic area; however, no significant improvement was noted with cricoid pressure. We therefore recommend the use of jaw thrust as a first-line maneuver to aid in glottic visualization and tracheal intubation during GlideScope videolaryngoscopy.

  2. Fundal Height: An Accurate Indicator of Fetal Growth?

    Science.gov (United States)

    Healthy Lifestyle Pregnancy week by week What's the significance of a fundal height measurement? Answers from Yvonne Butler Tobah, M. ... 2017 Original article: http://www.mayoclinic.org/healthy-lifestyle/pregnancy-week-by-week/expert-answers/fundal-height/faq- ...

  3. 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

  4. 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

  5. Effects of an alveolar recruitment maneuver on subdural pressure, brain swelling, and mean arterial pressure in patients undergoing supratentorial tumour resection: a randomized crossover study.

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    Flexman, Alana M; Gooderham, Peter A; Griesdale, Donald E; Argue, Ruth; Toyota, Brian

    2017-06-01

    Although recruitment maneuvers have been advocated as part of a lung protective ventilation strategy, their effects on cerebral physiology during elective neurosurgery are unknown. Our objectives were to determine the effects of an alveolar recruitment maneuver on subdural pressure (SDP), brain relaxation score (BRS), and cerebral perfusion pressure among patients undergoing supratentorial tumour resection. In this prospective crossover study, patients scheduled for resection of a supratentorial brain tumour were randomized to undergo either a recruitment maneuver (30 cm of water for 30 sec) or a "sham" maneuver (5 cm of water for 30 sec), followed by the alternative intervention after a 90-sec equilibration period. Subdural pressure was measured through a dural perforation following opening of the cranium. Subdural pressure and mean arterial pressure (MAP) were recorded continuously. The blinded neurosurgeon provided a BRS at baseline and at the end of each intervention. During each treatment, the changes in SDP, BRS, and MAP were compared. Twenty-one patients underwent the study procedure. The increase in SDP was higher during the recruitment maneuver than during the sham maneuver (difference, 3.9 mmHg; 95% confidence interval [CI], 2.2 to 5.6; P recruitment maneuver than in the sham maneuver (difference, -9.0 mmHg; 95% CI, -12.5 to -5.6; P recruitment maneuver. The BRS did not change with either maneuver. Our results suggest that recruitment maneuvers increase subdural pressure and reduce cerebral perfusion pressure, although the clinical importance of these findings is thus far unknown. This trial was registered with ClinicalTrials.gov, NCT02093117.

  6. Comparison of Baroreflex Sensitivity to Fall and Rise in Blood Pressure Induced by the Valsalva Maneuver

    Science.gov (United States)

    Wada, Naoki; Singer, Wolfgang; Gehrking, Tonette L.; Sletten, David M.; Schmelzer, James D.; Low, Phillip A.

    2014-01-01

    The baroreflex plays a key role in human blood pressure (BP) regulation. Its efferent limb consists of a vagal and a sympathetic component. The Valsalva maneuver is widely used to quantify vagal baroreflex function (vagal baroreflex sensitivity, BRS_vagal), but most studies have focused on the R-R interval response to BP decrement, even though the subsequent response to an increment in BP is important and different. We sought to evaluate if BRS_vagal can be determined from the rise in BP during phase III-IV of the Valsalva maneuver (BRSvagalinc), to assess the association between BRSvagalinc and BRS_vagal derived from the preceeding BP decrement (BRSvagaldec), and to validate BRSvagalinc as index of autonomic function. We studied patients with severe autonomic failure (n=49, 25 female), mild autonomic failure (n=25, 11 female), and matched normal controls (n=29, 15 female). BRSvagalinc and BRSvagaldec were calculated as the regression slope of R-R interval and systolic BP during phase III-IV and early phase II of the Valsalva maneuver, respectively, and compared with other autonomic indices across groups. BRSvagalinc could be calculated in all subjects and correlated highly with BRSvagaldec (r=0.72, p<0.001). BRSvagalinc also significantly correlated with BP changes during phase II and IV of the Valsalva maneuver and sympathetic barosensitivity. BRSvagalinc was significantly different between groups, being highest in controls and lowest in patients with severe autonomic failure. Vagal BRS, determined by relating R-R interval to BP increase following phase III, is a valuable autonomic index, provides additional information about vagal baroreflex function, and reflects overall severity of autonomic failure. PMID:24597842

  7. Remote Maneuver of Space Debris Using Photon Pressure for Active Collision Avoidance

    Science.gov (United States)

    Smith, C.

    2014-09-01

    The Space Environment Research Corporation (SERC) is a consortium of companies and research institutions that have joined together to pursue research and development of technologies and capabilities that will help to preserve the orbital space environment. The consortium includes, Electro Optics Systems (Australia), Lockheed Martin Australia, Optus Satellite Systems (Australia), The Australian national University, RMIT University, National Institute of Information and Communications Technology (NICT, Japan) as well as affiliates from NASA Ames and ESA. SERC is also the recipient of and Australian Government Cooperative Research Centre grant. SERC will pursue a wide ranging research program including technologies to improve tracking capability and capacity, orbit determination and propagation algorithms, conjunction analysis and collision avoidance. All of these technologies will contribute to the flagship program to demonstrate active collision avoidance using photon pressure to provide remote maneuver of space debris. This project joins of the proposed NASA Lightforce concept with infrastructure and capabilities provided by SERC. This paper will describe the proposed research and development program to provide an on-orbit demonstration within the next five years for remote maneuver of space debris.

  8. Pressure and tendon strain in the sixth extensor compartment of the wrist during simulated provocative maneuvers for diagnosing extensor carpi ulnaris tendinitis.

    Science.gov (United States)

    Kataoka, Toshiyuki; Moritomo, Hisao; Omori, Shinsuke; Iida, Akio; Omokawa, Shohei; Suzuki, Daisuke; Fujimiya, Mineko; Wada, Takuro; Aoki, Mitsuhiro; Yoshikawa, Hideki

    2015-11-01

    Various provocative maneuvers for diagnosing extensor carpi ulnaris (ECU) tendinitis have been reported; however, it remains unclear which maneuver is the most sensitive to detect ECU tendinitis. To clarify this, we investigated and compared the extratendinous pressure and ECU tendon strain in the sixth extensor compartment of the wrist during various provocative maneuvers for diagnosing ECU tendinitis. Nine upper extremities from nine fresh-frozen cadavers were examined. We investigated extratendinous pressure in the ECU fibro-osseous tunnel of the distal ulna and ECU tendon strain during eight forearm positions-neutral rotation, pronation, supination, pronation with wrist flexion, supination with wrist flexion, supination with wrist extension, both hand and forearm supination, and supination with ECU full loading-to simulate provocative maneuvers reported to detect ECU tendinitis. Pressure was significantly higher during both hand and forearm supination (carpal supination test) and during supination with wrist extension (prayer's hand supination test) than during neutral rotation. The pressure during the carpal supination test was 3 times higher than that during the prayer's hand supination test and 27 times higher than that during the neutral position. Strain was significantly higher during the carpal supination test and during supination with ECU full loading (the ECU synergy test) than during other maneuvers. Both pressure and tendon strain increased most notably during the carpal supination test compared to the other maneuvers, which suggests that the carpal supination test is the most sensitive for the detection of ECU tendinitis.

  9. Safety and effectiveness of alveolar recruitment maneuvers and positive end-expiratory pressure during general anesthesia for cesarean section: a prospective, randomized trial.

    Science.gov (United States)

    Aretha, D; Fligou, F; Kiekkas, P; Messini, C; Panteli, E; Zintzaras, E; Karanikolas, M

    2017-05-01

    During cesarean section, the supine position reduces functional residual capacity and worsens lung compliance. We tested the hypothesis that alveolar recruitment maneuvers and positive end-expiratory pressure improve lung compliance in women undergoing general anesthesia for cesarean section. Ninety women undergoing cesarean section were randomly assigned to one of two groups in a prospective, double-blind trial. In the alveolar recruitment maneuver group, pressure-control ventilation was used and inspiratory time was increased to 50% after delivery; positive end-expiratory pressure was increased to 20cmH2O and peak airway inspiratory pressure gradually increased to 45-50cmH2O. Volume-control ventilation was then used with low tidal volumes (6mL/kg) and positive end-expiratory pressure was reduced stepwise to 8cmH2O. In the control group, alveolar recruitment maneuvers were not used. Data were collected before and 3, 10 and 20min after the alveolar recruitment maneuver, before extubation and postoperatively at 10 and 20min. Dynamic compliance, peak airway inspiratory pressure, PaO2 and PaO2/FiO2 were significantly different in the alveolar recruitment maneuver group compared to controls at all time points during surgery except at baseline. Oxygen saturation was significantly greater in the alveolar recruitment maneuver group at 10 and 20min and before extubation. Dynamic compliance was 29.7-42.5% higher and peak airway inspiratory pressure 3.6-10.2% lower in the alveolar recruitment maneuver group compared to controls. The PaO2, PaO2/FiO2 and oxygen saturation were higher (9.4-12%, 10.3-11.9% and 0.4-1.3%, respectively) in the alveolar recruitment maneuver group. Postoperatively, PaO2 and oxygen saturation were significantly higher in the alveolar recruitment maneuver group compared to controls (PaO2 9.2% at 10min and 8.4% at 20min, oxygen saturation 0.8% at 10min and 1.1% at 20min). There were no significant differences in hemodynamic stability or adverse events

  10. Assessment of respiratory system compliance with electrical impedance tomography using a positive end-expiratory pressure wave maneuver during pressure support ventilation: a pilot clinical study.

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    Becher, Tobias H; Bui, Simon; Zick, Günther; Bläser, Daniel; Schädler, Dirk; Weiler, Norbert; Frerichs, Inéz

    2014-12-10

    Assessment of respiratory system compliance (Crs) can be used for individual optimization of positive end-expiratory pressure (PEEP). However, in patients with spontaneous breathing activity, the conventional methods for Crs measurement are inaccurate because of the variable muscular pressure of the patient. We hypothesized that a PEEP wave maneuver, analyzed with electrical impedance tomography (EIT), might be suitable for global and regional assessment of Crs during assisted spontaneous breathing. After approval of the local ethics committee, we performed a pilot clinical study in 18 mechanically ventilated patients (61 ± 16 years (mean ± standard deviation)) who were suitable for weaning with pressure support ventilation (PSV). For the PEEP wave, PEEP was elevated by 1 cmH2O after every fifth breath during PSV. This was repeated five times, until a total PEEP increase of 5 cmH2O was reached. Subsequently, PEEP was reduced in steps of 1 cmH2O in the same manner until the original PEEP level was reached. Crs was calculated using EIT from the global, ventral and dorsal lung regions of interest. For reference measurements, all patients were also examined during controlled mechanical ventilation (CMV) with a low-flow pressure-volume maneuver. Global and regional Crs(low-flow) was calculated as the slope of the pressure-volume loop between the pressure that corresponded to the selected PEEP and PEEP +5 cmH2O. For additional reference, Crs during CMV (Crs(CMV)) was calculated as expired tidal volume divided by the difference between airway plateau pressure and PEEP. Respiratory system compliance calculated from the PEEP wave (Crs(PEEP wave)) correlated closely with both reference measurements (r = 0.79 for Crs(low-flow) and r = 0.71 for Crs(CMV)). No significant difference was observed between the mean Crs(PEEP wave) and the mean Crs(low-flow). However, a significant bias of +17.1 ml/cmH2O was observed between Crs(PEEP wave) and Crs(CMV). Analyzing a PEEP wave

  11. [Morphometric characteristics of fundal glands of the stomach in duodenal ulcer and pre-ulcer condition].

    Science.gov (United States)

    Uspenskiĭ, V M

    1978-01-01

    Biopsy material was used for morphometric study of the fundal glands in 114 patients with duodenal ulcers, 177 patients with various forms of gastroduodenal pathology but with typical signs of duodenal ulcer, and in 21 normal subjects. Three variants of the increase in the amount of secretory elements of the fundal glands were found: owing to an increase in the number of main cells (first variant), main and parietal cells (second variant), and parietal cells (third variant). These changes in the fundal glands are not specific for ulcer and pre-ulcer conditions, they are observed in normal subjects with constitutional hypersecretion of hydrochloric acid and pepsin. The patients with duodenal ulcer and pre-ulcer conditions are characterized by "hyper-pepsinogenic shift" in the epithelial formula of the fundal gland (45% and 31-38%, respectively) owing to an increase in the number of main cells.

  12. Spontaneous unscarred fundal rupture after normal vaginal delivery

    Directory of Open Access Journals (Sweden)

    Shreya Thapa

    2014-06-01

    Full Text Available Uterine rupture is one of the most dangerous obstetric situation carrying an increased risk of maternal and perinatal morbidity and mortality, associated with poorly managed labour. The incidence of spontaneous rupture of unscarred uterus is around 1 in 8000 to 1 in 15000 deliveries. We report this unusual case of spontaneous unscarred fundal rupture after normal vaginal delivery. This case under reference developed shock soon after delivery and was explored due to suspected intraperitoneal hemorrhage. This case is being reported to emphasis the need for proper post-delivery monitoring not only to diagnose post-partum hemorrhage but also to suspect uterine rupture as a cause of unexplained shock developing after delivery inspite of all resuscitative measures. Although unexpected in a woman with an unscarred uterus, rupture should be considered as a possible cause of unusual pain or hypotension in the mother. The most effective way to reduce the number of morbidity and mortality would be to prevent unwanted pregnancies by informed and effective use of contraception. [Int J Reprod Contracept Obstet Gynecol 2014; 3(3.000: 780-782

  13. Skin microvascular and metabolic response to pressure relief maneuvers in people with spinal cord injury

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    Ramella-Roman, Jessica C.; Le, Du V. N.; Ghassemi, Pejhman; Nguyen, Thu A.; Lichy, Alison; Groah, Suzanne

    2013-02-01

    Clinician's recommendations on wheelchair pressure reliefs in the context of the high prevalence of pressure ulcers that occur in people with spinal cord injury is not supported by strong experimental evidence. Some data indicates that altered tissue perfusion and oxygenation occurring under pressure loads, such as during sitting, induce various pathophysiologic changes that may lead to pressure ulcers. Pressure causes a cascade of responses, including initial tissue hypoxia, which leads to ischemia, vascular leakage, tissue acidification, compensatory angiogenesis, thrombosis, and hyperemia, all of which may lead to tissue damage. We have developed an advanced skin sensor that allows measurement of oxygenation in addition to perfusion, and can be safely used during sitting. The sensor consists of a set of fiber optics probes, spectroscopic and Laser Doppler techniques that are used to obtain parameters of interest. The overriding goal of this project is to develop the evidence base for clinical recommendations on pressure reliefs. In this paper we will illustrate the experimental apparatus as well as some preliminary results of a small clinical trial conducted at the National Rehabilitation Hospital.

  14. Dynamic changes in optic disc morphology, choroidal thickness, anterior chamber parameters, and intraocular pressure during Valsalva maneuver

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    Alper Mete

    Full Text Available ABSTRACT Purpose: To investigate the effects of the Valsalva maneuver (VM on optic disc morphology, choroidal thickness, and anterior chamber parameters. Methods: This prospective observational study included 60 eyes of 60 healthy subjects. The anterior chamber parameters, including central corneal thickness (CCT, anterior chamber depth (ACD, anterior chamber angle (ACA, anterior chamber volume (ACV, pupil diameter (PD, axial length (AL, subfoveal and peripapillary choroidal thickness, optic disc parameters, and intraocular pressure (IOP, were measured at rest and during VM. Results: VM did not have any significant influence on AL, subfoveal and peripapillary choroidal thickness, optic disc area, rim area, cup area, cup-to-disc area ratio, vertical cup-to-disc ratio, rim volume, cup volume, and nerve head volume measurements (for all; p >0.05. IOP and PD significantly increased during VM (for both; p <0.001. VM significantly decreased CCT, ACD, ACA, and ACV values (for all; p <0.001. Moreover, the optic nerve cup volume decreased and the horizontal cup-to-disc ratio significantly increased during VM (for both; p <0.05. Conclusions: VM may cause transient changes in IOP, optic disc morphology, and anterior chamber parameters.

  15. Epley maneuver

    Science.gov (United States)

    ... Canalith-Repositioning Maneuvers; CRP; Benign positional vertigo-Epley; Benign paroxysmal positional vertigo-Epley; BPPV-Epley ... Bronston LJ, Cass S, et al. Clinical practice guideline: Benign ... vertigo. Otolaryngology: Head and Neck Surgery . 2008;139(5 ...

  16. Pneumomediastinum following the Heimlich maneuver.

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    Agia, G A; Hurst, D J

    1979-11-01

    The Heimlich maneuver appears to be a widely accepted technique advocated as a means of clearing an obstructed airway. Reports of complications have been few. We report a case of pneumomediastinum that occurred following the generation of increased pulmonary pressures during performance of the Heimlich maneuver.

  17. Evaluation of some pulmonary functions and pleuropulmonary complications after endoscopic sclerotherapy of gastric fundal varices at Zagazig university hospitals

    Directory of Open Access Journals (Sweden)

    Jihan A. Shawky

    2016-10-01

    Conclusions: NBCA injection of gastric fundal varices was associated with significant, reversible deterioration in some pulmonary functions, atelectasis and minimal pleural effusion with significant rapid improvement if incentive spirometry is used.

  18. Symphysis-fundal height curve in the diagnosis of fetal growth deviations

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    Djacyr Magna Cabral Freire

    2010-12-01

    Full Text Available OBJECTIVE: To validate a new symphysis-fundal curve for screening fetal growth deviations and to compare its performance with the standard curve adopted by the Brazilian Ministry of Health. METHODS: Observational study including a total of 753 low-risk pregnant women with gestational age above 27 weeks between March to October 2006 in the city of João Pessoa, Northeastern Brazil. Symphisys-fundal was measured using a standard technique recommended by the Brazilian Ministry of Health. Estimated fetal weight assessed through ultrasound using the Brazilian fetal weight chart for gestational age was the gold standard. A subsample of 122 women with neonatal weight measurements was taken up to seven days after estimated fetal weight measurements and symphisys-fundal classification was compared with Lubchenco growth reference curve as gold standard. Sensitivity, specificity, positive and negative predictive values were calculated. The McNemar χ2 test was used for comparing sensitivity of both symphisys-fundal curves studied. RESULTS: The sensitivity of the new curve for detecting small for gestational age fetuses was 51.6% while that of the Brazilian Ministry of Health reference curve was significantly lower (12.5%. In the subsample using neonatal weight as gold standard, the sensitivity of the new reference curve was 85.7% while that of the Brazilian Ministry of Health was 42.9% for detecting small for gestational age. CONCLUSIONS: The diagnostic performance of the new curve for detecting small for gestational age fetuses was significantly higher than that of the Brazilian Ministry of Health reference curve.

  19. Percutaneous transsplenic embolization of esophageal and gastrio- fundal varicesin 18 patients

    Institute of Scientific and Technical Information of China (English)

    Gao-Quan Gong; Xiao-Lin Wang; Jian-Hua Wang; Zhi-Ping Yan; Jie-Min Cheng; Sheng Qian; Yi Chen

    2001-01-01

    AIM: Clinical application and potential complication of percutaneous transsplenic varices embolization (PTSVE) of esophageal or gastrio-fundal varices in patients with hepatocellular carcinoma (HCC) complicated with portal vein cancerous thrombosis (PVCT). METHODS: 18 patients with HCC complicated with PVCT and esophageal or gastrio-fundal varices who underwent PTSVE were collected. The rate of success, complication, mortality of the procedure and postoperative complication were recorded and analyzed. RESULTS: PTSVE were successfully performed in 16 of 18cases, and the rate of success was 89%. After therapy erythrocyte counts decreased in all of the natunts. 5 of patients needed blood transfusion, 2 patients requiredsurgical intervention because of and 11 patients with ascites were alleviated by diuresis. Among these 18patients, the procedure-related mortality was 11% (2/18),one died of acute hepatic failure on the forth day after procedure, another died of acute renal failure on the fifth day. The patients were follow up for 112 mon exceptone. 13of them died of their tumors but none of them experienced variceal bleeding. CONCLUSION: PTSVE is a relatively safe and effective method to treat esophageal or gastrio-fundal varices in HCCpatients with PVCT when percutaneous transhepatic varices embolization (PTHVE) of varices is impossible.

  20. Heimlich maneuver on self

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    ... this page: //medlineplus.gov/ency/article/001983.htm Heimlich maneuver on self To use the sharing features on ... are choking on something, you can perform the Heimlich maneuver on yourself. Follow these steps: Make a fist ...

  1. Choking (Heimlich Maneuver)

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    ... A-Z Share this! Home » Emergency 101 Choking (Heimlich Maneuver) ACEP recommends that the Heimlich Maneuver be employed only when a person is choking ... death. Avoid using excessive force in employing the Heimlich Maneuver to avoid injury to the ribs or internal ...

  2. 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; Illsley, Jeannette

    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.

  3. Management of gastric fundal varices without gastro-renal shunt in 15 patients

    Institute of Scientific and Technical Information of China (English)

    Natsuhiko Kameda; Yasuhiro Fujiwara; Kenji Nakamura; Tetsuo Arakawa; Kazuhide Higuchi; Masatsugu Shiba; Kaori Kadouchi; Hirohisa Machida; Hirotoshi Okazaki; Tetsuya Tanigawa; Toshio Watanabe; Kazunari Tominaga

    2008-01-01

    AIM: To examine the portal hemodynamics of gastric fundal varices (GV) without gastro-renal shunt (GRS), and to retrospectively investigate the effects of various kinds of treatment on eradication. METHODS: Ninety-four liver cirrhosis patients at high- risk of GV were treated in our hospital and enrolled in this study. We retrospectively examined their characteristics, liver function, and portal hemodynamics of GV. We performed balloon-occluded retrograde transvenous obliteration (BRTO) at first. If it was not technically possible to perform BRTO, endoscopic injection sclerotherapy using α-cyanoacrylate glue (CA) or percutaneous transhepatic obliteration (PTO) was performed. RESULTS: Among the 94 patients, a GRS was present in 79 (84.0%), and absent in the remaining 15 (16.0%). The subphrenic vein was connected to the inferior vena cava as the drainage vein in 13 (86.7%) out of the 15 cases without GRS. We performed BRTO in 6 patients, CA in 4 patients and PTO in 5 patients. The eradication rate was 100% for each procedure, but the rate of early recurrence within 6 mo was 16.7% for BRTO, 50.0% for CA and 40.0% for PTO, respectively. CONCLUSION: We should examine the hemodynamics before treatment of GV irrespective of the existence of GRS. If this hemodynamic examination reveals that the drainage vein connects directly to the inferior vena cava in GV without GRS, BRTO may be an effective treatment for GV with GRS.

  4. Perforated stomach following the Heimlich maneuver.

    Science.gov (United States)

    Cowan, M; Bardole, J; Dlesk, A

    1987-03-01

    The use of infradiaphragmatic abdominal pressure for relief of airway obstruction caused by food was first described by Henry Heimlich in 1974. Since that time, several complications have been reported. We report a case of gastric perforation occurring in a choking victim following the application of the Heimlich maneuver.

  5. Nonlinear Maneuver Autopilot

    Science.gov (United States)

    Menon, P. K. A.; Badgett, M. E.; Walker, R. A.

    1992-01-01

    Trajectory-control laws based on singular-perturbation theory and nonlinear dynamical modeling. Nonlinear maneuver autopilot commands flight-test trajectories of F-15 airplane. Underlying theory of controller enables separation of variables processed in fast and slow control loops, reducing amount of computation required.

  6. The Valsalva maneuver: mechanisms and clinical implications.

    Science.gov (United States)

    Porth, C J; Bamrah, V S; Tristani, F E; Smith, J J

    1984-09-01

    The previous discussion has focused on the mechanisms, both respiratory and circulatory, that occur during the Valsalva maneuver. The increase in intrathoracic pressure that occurs during the Valsalva maneuver incites a sequence of rapid changes in preload and afterload stress. During the strain, venous return to the heart is decreased and peripheral venous pressures become increased. Within the next few beats, systolic and pulse pressures begin to fall while mean arterial pressure remains near (or is elevated above) control levels owing to the transmission of airway pressure. Thus it would appear that the benefits to cardiac contractility derived from a decrease in systolic and pulse pressure are counterbalanced by an increase in mean arterial pressure. Increases in total peripheral resistance that begin after about 7 seconds of strain produce further increases in afterload. Recruitment of autonomically mediated increases in heart rate and cardiac contractility assists the heart to maintain its cardiac output in the presence of diminished venous return. With the increased venous return that accompanies termination of Valsalva strain, there is an increase in diastolic filling and stroke volume output by means of the Frank-Starling mechanism. Heart rate and total peripheral resistance continue to be increased during the immediate poststrain period, and the ejection of an increased stroke volume into a constricted arterial system produces a rapid and marked increase in arterial pressure--the phase IV overshoot with its subsequent slowing of heart rate.

  7. Nonlinear maneuver autopilot for the F-15 aircraft

    Science.gov (United States)

    Menon, P. K. A.; Badgett, M. E.; Walker, R. A.

    1989-01-01

    A methodology is described for the development of flight test trajectory control laws based on singular perturbation methodology and nonlinear dynamic modeling. The control design methodology is applied to a detailed nonlinear six degree-of-freedom simulation of the F-15 and results for a level accelerations, pushover/pullup maneuver, zoom and pushover maneuver, excess thrust windup turn, constant thrust windup turn, and a constant dynamic pressure/constant load factor trajectory are presented.

  8. Structural Dynamics of Maneuvering Aircraft.

    Science.gov (United States)

    1987-09-01

    AD-RI92 376 STRUCTURAL DYNAMICS OF MANEUVERING RIRCRAFT(U) CONRAD I TECHNOLOGIES INC KING OF PRUSSIA PR M M REDDI SEP 97 CTI-8601 NRDC-88014-69...REPORT NO. NADC-8014-60 STRUCTURAL DYNAMICS OF MANEUVERING AIRCRAFT M. Mahadeva Reddi .4 Conrad Technologies, Inc. 650 S. Henderson Rd. D T IQ King of...NO A0 CCESSION NO. R02303001 107601 11. TITLE (Include Security Classfication) (u) STRUCTURAL DYNAMICS OF MANEUVERING AIRCRAFT 12. PERSONAL AUTHORS) M

  9. Ruptured jejunum following Heimlich maneuver.

    Science.gov (United States)

    Razaboni, R M; Brathwaite, C E; Dwyer, W A

    1986-01-01

    The Heimlich maneuver, over time, has proved to be a useful resuscitative procedure in the management of cases with airway occlusion secondary to foreign body. Medical treatments, however, can have side effects, and this maneuver is no exception. A previously unreported complication is presented, that of jejunal rupture. The proper application of the maneuver minimizes the number of side effects; however, since they do occur, it is suggested that all persons subject to this maneuver be subsequently evaluated by a physician as soon after the incident as is practicable.

  10. 体位改变对Valsalva动作心率、血压响应模式的影响%Posture shift alters pattern of heart rate and blood pressure response during valsalva maneuver

    Institute of Scientific and Technical Information of China (English)

    程九华; 王守岩; 张海宁; 缴富斌; 张立藩

    2001-01-01

    目的比较不同体位下进行Valsalva动作时,心血管响应型式的差别. 方法在-15°头低位倾斜、水平仰卧和+75°头高位倾斜三种体位下,分别进行4 kPa /30s的Valsalva动作,并记录逐跳心率及动脉血压变化. 结果 +75°头高位倾斜体位下,心率在Ⅱ相的增高幅度最大;在Ⅲ相时呈降低变化,而在另外两种体位下则呈升高变化. 血压在Ⅱ相前期的降低幅度以在-15°头低位倾斜体位下为最小,在+75°头高位倾斜体位下为最大. +75°头高位倾斜体位下血压在Ⅲ相呈升高反应,而在-15°头低位倾斜和水平仰卧体位下血压呈典型降低变化. 体位改变对Valsalva动作II相心率、血压响应模式的影响最大. 结论体位改变可引起中心血量重新分配及自主神经均衡性改变,故对Valsalva动作时心率和血压的响应模式产生影响.%AIM To examine the influence of posture shift on the pattern of heart rate and blood pressure response to Valsalva. METHODS Thirty seconds Valsalva maneuver strains at 4 kPa were performed under -15° head-down tilt, supine or +75° head-up tilt posture, and the beat-by-beat changes of heart rate and blood pressure were noninvasively recorded and analyzed. RESULTS The increasing change of heart rate for phase Ⅱ under +75° head-up tilt was beyond that under the other two postures. Under +75° head-up tilt, the heart rate decreased during phase Ⅲ, whereas under horizontal supine or -15° head-down tilt posture, the heat rate manifested an increasing change. The decreasing change of blood pressure during early phase Ⅱ was lowest under -15° head-down tilt, and highest under +75° head-up tilt. Blood pressure increased during phase Ⅲ under +75° head-up tilt, and decreased under other two postures. CONCLUSION Posture shift alters the response pattern of heart rate and blood pressure during Valsalva maneuver, by circulating blood volume redistribution and

  11. Where is the best site for embryo transfer? A study of relation of embryo-fundal distance with pregnancy rate in ICSI-ET cycle

    Directory of Open Access Journals (Sweden)

    Shreedevi J. Tanksale

    2016-08-01

    Conclusions: The present study demonstrates that higher pregnancy rates are obtained if the embryos are selectively placed at a distance between 10mm to 15 mm from the fundal endometrial surface. It is not possible to determine exact location of embryo placed in utero by any method. The findings of our study can be considered as a guiding force by clinicians. [Int J Reprod Contracept Obstet Gynecol 2016; 5(8.000: 2661-2665

  12. Contrast-enhanced MR angiography for differentiation between perigastric and submucosal gastric fundal varices; Kontrastmittelverstaerkte MR-Angiographie zur Differenzierung zwischen perigastrischen und submukoesen Fundusvarizen des Magens

    Energy Technology Data Exchange (ETDEWEB)

    Willmann, J.K.; Boehm, T.; Lutz, A.M.; Goepfert, K.; Marincek, B.; Weishaupt, D. [Inst. fuer Diagnostische Radiologie, Universitaetsspital Zuerich (Switzerland); Bauerfeind, P. [Abt. fuer Gastroenterologie, Universitaetsspital Zuerich (Switzerland)

    2003-04-01

    Purpose: To evaluate contrast-enhanced MR angiography for the distinction between perigastric and submucosal fundal varices. Materials and Methods: Nineteen consecutive patients with clinically suspected fundal varices underwent contrast-enhanced MR angiography and endoscopic ultrasound (EUS) within one week. Diagnostic confidence for the detection of perigastric and submucosal fundal varices was compared between MR angiography (two radiologists) and EUS (one gastroenterologist), and the agreement of size and location was evaluated. Results: Both MR angiography and EUS detected perigastric varices in all 19 patients and submucosal fundal varices in 14 of the 19 patients. The interobserver reliability of MR angiography was good for measuring the variceal diameter ({kappa} = 0.76) and excellent for localizing the varices ({kappa} = 1.0). EUS and MR angiography agreed in 12 of 14 patients (86%) in determining variceal diameter and location. Conclusions: Contrast-enhanced MR angiography is comparable to endoscopic ultrasound in the detection and characterization of gastric fundal varices. (orig.) [German] Fragestellung: Das Ziel dieser Studie war es, die kontrastmittelverstaerkte MR-Angiographie bei der Diagnose von Fundusvarizen des Magens, insbesondere bei der Differenzierung von perigastrischen und submukoesen Fundusvarizen mit dem endoskopischen Ultraschall (EUS) zu vergleichen. Methoden: Neunzehn Patienten mit klinischem Verdacht auf Fundusvarizen wurden prospektiv in die Studie eingeschlossen und innerhalb einer Woche mittels kontrastmittelverstaerkter MR-Angiographie und EUS untersucht. Die Uebereinstimmungen zwischen MR-Angiographie (Radiologe 1 und 2) und EUS (1 Gastroenterologe) bei der diagnostischen Sicherheit bezueglich der Diagnose perigastrischer und submukoeser Fundusvarizen sowie bei der Groessen- und Lokalisationsbestimmung submukoeser Fundusvarizen wurden untersucht. Ergebnisse: Sowohl bezueglich der Diagnose perigastrischer (19/19 Patienten) als

  13. 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.

  14. 14 CFR 25.1507 - Maneuvering speed.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Maneuvering speed. 25.1507 Section 25.1507....1507 Maneuvering speed. The maneuvering speed must be established so that it does not exceed the design maneuvering speed V A determined under § 25.335(c)....

  15. Dynamics of Voluntary Cough Maneuvers

    Science.gov (United States)

    Naire, Shailesh

    2008-11-01

    Voluntary cough maneuvers are characterized by transient peak expiratory flows (PEF) exceeding the maximum expiratory flow-volume (MEFV) curve. In some cases, these flows can be well in excess of the MEFV, generally referred to as supramaximal flows. Understanding the flow-structure interaction involved in these maneuvers is the main goal of this work. We present a simple theoretical model for investigating the dynamics of voluntary cough and forced expiratory maneuvers. The core modeling idea is based on a 1-D model of high Reynolds number flow through flexible-walled tubes. The model incorporates key ingredients involved in these maneuvers: the expiratory effort generated by the abdominal and expiratory muscles, the glottis and the flexibility and compliance of the lung airways. Variations in these allow investigation of the expiratory flows generated by a variety of single cough maneuvers. The model successfully reproduces PEF which is shown to depend on the cough generation protocol, the glottis reopening time and the compliance of the airways. The particular highlight is in simulating supramaximal PEF for very compliant tubes. The flow-structure interaction mechanisms behind these are discussed. The wave speed theory of flow limitation is used to characterize the PEF. Existing hypotheses of the origin of PEF, from cough and forced expiration experiments, are also tested using this model.

  16. Maneuvering impact boring head

    Science.gov (United States)

    Zollinger, W. Thor; Reutzel, Edward W.

    1998-01-01

    An impact boring head may comprise a main body having an internal cavity with a front end and a rear end. A striker having a head end and a tail end is slidably mounted in the internal cavity of the main body so that the striker can be reciprocated between a forward position and an aft position in response to hydraulic pressure. A compressible gas contained in the internal cavity between the head end of the striker and the front end of the internal cavity returns the striker to the aft position upon removal of the hydraulic pressure.

  17. Pre-treatment hemodynamic features involved with long-term survival of cirrhotic patients after embolization of gastric fundal varices

    Energy Technology Data Exchange (ETDEWEB)

    Maruyama, Hitoshi, E-mail: maru-cib@umin.ac.j [Department of Medicine and Clinical Oncology, Chiba University Graduate School of Medicine, 1-8-1, Inohana, Chuou-ku, Chiba, 260-8670 (Japan); Okugawa, Hidehiro, E-mail: hideun@yahoo.co.j [Department of Medicine and Clinical Oncology, Chiba University Graduate School of Medicine, 1-8-1, Inohana, Chuou-ku, Chiba, 260-8670 (Japan); Kobayashi, Satoshi, E-mail: kobakobakopa@yahoo.co.j [Department of Medicine and Clinical Oncology, Chiba University Graduate School of Medicine, 1-8-1, Inohana, Chuou-ku, Chiba, 260-8670 (Japan); Yoshizumi, Hiroaki, E-mail: yossih04@yahoo.co.j [Department of Medicine and Clinical Oncology, Chiba University Graduate School of Medicine, 1-8-1, Inohana, Chuou-ku, Chiba, 260-8670 (Japan); Yokosuka, Osamu, E-mail: yokosukao@faculty.chiba-u.j [Department of Medicine and Clinical Oncology, Chiba University Graduate School of Medicine, 1-8-1, Inohana, Chuou-ku, Chiba, 260-8670 (Japan)

    2010-08-15

    Purpose: To clarify the pre-treatment hemodynamic features involved in the long-term survival of cirrhotic patients with gastric fundal varices (FV) after balloon-occluded retrograde transvenous obliteration (B-RTO). Materials and methods: Eighty-one cirrhotic patients with medium- or large-grade FV treated by B-RTO were enrolled in this retrospective study. Pre-treatment flow volume ratio between gastric vein and portal trunk (GP-R) was obtained by Doppler ultrasound. Results: The cumulative survival rate was 90% at 1 year, 74.8% at 3 years, 57.2% at 5 years, and 45.8% at 7 years without recurrence in a median period of 1148.5 days The survival was poorer in patients with HCC (47% at 3 years, 9.4% at 5 years, p < 0.0001) than without (89.2% at 3 years, 81.9% at 5 years, 67.5% at 7 years), in patients with Child B/C (57.7% at 3 years, 42.1% at 5 years, 28.1% at 7 years, p = 0.0016) than with Child A (91.8% at 3 years, 71.5% at 5 years, 62.1% at 7 years), and in patients with GP-R {>=} 1.0 (58.9% at 3 years, p = 0.0485) than with GP-R < 1.0 (76.3% at 3 years, 62% at 5 years, 49.6% at 7 years). Multivariate analysis identified the presence of HCC (hazard ratio, 12.486; 95% CI, 4.08-38.216; p < 0.0001), Child B/C (hazard ratio, 3.41; 95% CI, 1.594-7.15; p = 0.0051) and GP-R {>=} 1.0 (hazard ratio, 2.701; 95% CI, 1.07-6.15; p = 0.0221) as independent factors for poor prognosis. Conclusion: GP-R {>=} 1.0 on Doppler ultrasound before B-RTO may be a predictive indicator for poor prognosis in cirrhotic patients with FV after B-RTO, in addition to the presence of HCC and severe liver damage.

  18. Time frequency analysis of sound from a maneuvering rotorcraft

    Science.gov (United States)

    Stephenson, James H.; Tinney, Charles E.; Greenwood, Eric; Watts, Michael E.

    2014-10-01

    The acoustic signatures produced by a full-scale, Bell 430 helicopter during steady-level-flight and transient roll-right maneuvers are analyzed by way of time-frequency analysis. The roll-right maneuvers comprise both a medium and a fast roll rate. Data are acquired using a single ground based microphone that are analyzed by way of the Morlet wavelet transform to extract the spectral properties and sound pressure levels as functions of time. The findings show that during maneuvering operations of the helicopter, both the overall sound pressure level and the blade-vortex interaction sound pressure level are greatest when the roll rate of the vehicle is at its maximum. The reduced inflow in the region of the rotor disk where blade-vortex interaction noise originates is determined to be the cause of the increase in noise. A local decrease in inflow reduces the miss distance of the tip vortex and thereby increases the BVI noise signature. Blade loading and advance ratios are also investigated as possible mechanisms for increased sound production, but are shown to be fairly constant throughout the maneuvers.

  19. Operational Maneuver: Function or Fiction?

    Science.gov (United States)

    2007-11-02

    the premise that this would never happen, so why plan for it. That is just the point. Operational art planning should not leave any stone unturned . The... unturned during operational art planning and execution. The maneuver apex theory can be applied to the Air Force operating environment, however, operational

  20. 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...

  1. Ground Target Overflight and Orbital Maneuvering via Atmospheric Maneuvers

    Science.gov (United States)

    2014-03-27

    al., 2002:228-230). Prior to the commencement of any research into aeroassisted maneuvers, a firm foundation in the understanding of atmospheric...cosine term is used for prograde orbits while the negative term is used for retrograde orbits. The r(1), r(2), and r(3) terms rerpresent the 1st... retrograde ) only target longitude crossings which occur in the same hemisphere as the 44 target are possible to overfly without changing the inclination

  2. Cassini Solstice Mission Maneuver Experience: Year Three

    Science.gov (United States)

    Wagner, Sean V.; Arrieta, Juan; Hahn, Yungsun; Stumpf, Paul W.; Valerino, Powtawche N.; Wong, Mau C.

    2013-01-01

    The Solstice Mission is the final extension of the Cassini spacecraft s tour of Saturn and its moons. To accommodate an end-of-mission in 2017, the maneuver decision process has been refined. For example, the Cassini Project now prioritizes saving propellant over minimizing maneuver cycles. This paper highlights 30 maneuvers planned from June 2012 through July 2013, targeted to nine Titan flybys and the final Rhea encounter in the mission. Of these maneuvers, 90% were performed to maintain the prescribed trajectory and preserve downstream delta V. Recent operational changes to maneuver executions based on execution-error modeling and analysis are also discussed.

  3. 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.

  4. Avaliação da frequência cardíaca à medida de pressão expiratória máxima estática e à manobra de Valsalva em jovens saudáveis Heart rate assessment during maximal static expiratory pressure and Valsalva maneuver in healthy young men

    Directory of Open Access Journals (Sweden)

    Vinicius Minatel

    2012-10-01

    Full Text Available CONTEXTUALIZAÇÃO: A medida de pressão expiratória máxima (PEmáx possui algumas contraindicações, pois acredita-se que as respostas obtidas nessa medida são similares às respostas encontradas na manobra de Valsalva (MV. OBJETIVOS: O objetivo principal é avaliar a resposta da frequência cardíaca (FC durante a medida da PEmáx e da MV em jovens saudáveis, em diferentes posturas, para identificar se e em qual condição a PEmáx reproduz as respostas obtidas na MV e, adicionalmente, estimar o trabalho realizado nas manobras. MÉTODO: Doze jovens saudáveis foram avaliados, orientados e familiarizados com as manobras. A MV foi composta por um esforço expiratório (40 mmHg durante 15 segundos contra um manômetro. A PEmáx foi executada segundo a American Thoracic Society. Ambas as medidas foram realizadas nas posturas supino e sentado. Para a análise da variação da frequência cardíaca (∆FC, índice de Valsalva (IV, índice da PEmáx (IPEmáx e o trabalho estimado das manobras (Wtotal, Wisotime, Wtotal/∆FCtotal e Wisotime/∆FCisotime , utilizou-se ANOVA two-way com post-hoc de Holm-Sidak (pBACKGROUND: The measure of the maximal expiratory pressure (MEP has some contraindications, as it is believed that the responses obtained in this measure are similar to the Valsalva maneuver (VM. OBJECTIVE: The main purpose of this study was to evaluate the heart rate responses (HR during the MEP and the VM measures in healthy young men into different postures aiming to identify whether and in which situation the MEP reproduces the responses obtained in the VM. Additionally we aim to estimate the workload realized during the maneuvers. METHOD: Twelve healthy young men were evaluated, instructed and familiarized with the maneuvers. The VM was characterized by an expiratory effort (40 mmHg against a manometer for 15 seconds. The MEP measure has been performed according to the American Thoracic Society. Both measures were performed at sitting

  5. Efficacy of balloon-occluded retrograde transvenous obliteration,percutaneous transhepatic obliteration and combined techniques for the management of gastric fundal varices

    Institute of Scientific and Technical Information of China (English)

    Hirotaka Arai; Takehiko Abe; Hitoshi Takagi; Masatomo Mori

    2006-01-01

    AIM: To evaluate the effect of three interventional treatments involving transvenous obliteration for the treatment of gastric varices, and to compare the efficacy and adverse effects of these methods.METHODS: From 1995 to 2004, 93 patients with gastric fundal varices underwent interventional radiologic embolotherapy at our hospital. Of the 93 patients, 75 were treated with the balloon-occluded retrograde transvenous obliteration (BRTO) procedure; 8 were with the percutaneous transhepatic obliteration (PTO)procedure; and 10 were with the combined BRTO and PTO therapy. A follow-up evaluation examined the rates of survival, recurrence and rebleeding of the gastric varices, worsening of esophageal varices and complications in each group.RESULTS: The BRTO, PTO, and combined therapy were technically successful in 81% (75/93), 44% (8/18),and 100% (10/10) patients, respectively. Recurrence of gastric varices was found in 3 patients in the BRTO group and in 3 patients in the PTO group. Rebleeding was observed in 1 patient in the BRTO group and in 1 patient in the PTO group. The 1- and 3-year survival rates were 98% and 87% in the patients without hepatocellular carcinoma (HCC) in the BRTO group, 100% and 100% in the PTO group, and 90% and 75% in the combined therapy group, respectively.CONCLUSION: Combined BRTO and PTO therapy may rescue cases with uncontrollable gastric fundal varices that remained even after treatment with BRTO and/or PTO, though there were limitations of our study,including retrospective nature and discrepancy in sample size between the BRTO, PTO and combined therapy groups.

  6. Changes in Stroke Volume Induced by Lung Recruitment Maneuver Predict Fluid Responsiveness in Mechanically Ventilated Patients in the Operating Room.

    Science.gov (United States)

    Biais, Matthieu; Lanchon, Romain; Sesay, Musa; Le Gall, Lisa; Pereira, Bruno; Futier, Emmanuel; Nouette-Gaulain, Karine

    2017-02-01

    Lung recruitment maneuver induces a decrease in stroke volume, which is more pronounced in hypovolemic patients. The authors hypothesized that the magnitude of stroke volume reduction through lung recruitment maneuver could predict preload responsiveness. Twenty-eight mechanically ventilated patients with low tidal volume during general anesthesia were included. Heart rate, mean arterial pressure, stroke volume, and pulse pressure variations were recorded before lung recruitment maneuver (application of continuous positive airway pressure of 30 cm H2O for 30 s), during lung recruitment maneuver when stroke volume reached its minimal value, and before and after volume expansion (250 ml saline, 0.9%, infused during 10 min). Patients were considered as responders to fluid administration if stroke volume increased greater than or equal to 10%. Sixteen patients were responders. Lung recruitment maneuver induced a significant decrease in mean arterial pressure and stroke volume in both responders and nonresponders. Changes in stroke volume induced by lung recruitment maneuver were correlated with those induced by volume expansion (r = 0.56; P recruitment maneuver predicted fluid responsiveness with a sensitivity of 88% (95% CI, 62 to 98) and a specificity of 92% (95% CI, 62 to 99). Pulse pressure variations more than 6% before lung recruitment maneuver discriminated responders with a sensitivity of 69% (95% CI, 41 to 89) and a specificity of 75% (95% CI, 42 to 95). The area under receiver operating curves generated for changes in stroke volume induced by lung recruitment maneuver (0.96; 95% CI, 0.81 to 0.99) was significantly higher than that for pulse pressure variations (0.72; 95% CI, 0.52 to 0.88; P recruitment maneuver could predict preload responsiveness in mechanically ventilated patients in the operating room.

  7. Traumatic dissection and rupture of the abdominal aorta as a complication of the Heimlich maneuver.

    Science.gov (United States)

    Desai, Shaun C; Chute, Dennis J; Desai, Bharati C; Koloski, Eugene R

    2008-11-01

    Although the Heimlich maneuver is considered the best intervention for relieving acute upper airway obstruction, several complications have been reported in the literature. These complications can occur as a result of an increase in abdominal pressure leading to a variety of well-documented visceral injuries, including the great vessels. Acute abdominal aortic thrombosis after the Heimlich maneuver is a rare but recognized event; however, to date no case of traumatic dissection and rupture of the abdominal aorta has been described. We report the first known case, to our knowledge, of a traumatic dissection and rupture of the abdominal aorta after a forcefully applied Heimlich maneuver.

  8. Direct lateral maneuvers in hawkmoths

    Directory of Open Access Journals (Sweden)

    Jeremy S. M. Greeter

    2016-01-01

    Full Text Available We used videography to investigate direct lateral maneuvers, i.e. ‘sideslips’, of the hawkmoth Manduca sexta. M. sexta sideslip by rolling their entire body and wings to reorient their net force vector. During sideslip they increase net aerodynamic force by flapping with greater amplitude, (in both wing elevation and sweep, allowing them to continue to support body weight while rolled. To execute the roll maneuver we observed in sideslips, they use an asymmetric wing stroke; increasing the pitch of the roll-contralateral wing pair, while decreasing that of the roll-ipsilateral pair. They also increase the wing sweep amplitude of, and decrease the elevation amplitude of, the contralateral wing pair relative to the ipsilateral pair. The roll maneuver unfolds in a stairstep manner, with orientation changing more during downstroke than upstroke. This is due to smaller upstroke wing pitch angle asymmetries as well as increased upstroke flapping counter-torque from left-right differences in global reference frame wing velocity about the moth's roll axis. Rolls are also opposed by stabilizing aerodynamic moments from lateral motion, such that rightward roll velocity will be opposed by rightward motion. Computational modeling using blade-element approaches confirm the plausibility of a causal linkage between the previously mentioned wing kinematics and roll/sideslip. Model results also predict high degrees of axial and lateral damping. On the time scale of whole and half wing strokes, left-right wing pair asymmetries directly relate to the first, but not second, derivative of roll. Collectively, these results strongly support a roll-based sideslip with a high degree of roll damping in M. sexta.

  9. A Novel Method for Satellite Maneuver Prediction

    Science.gov (United States)

    Shabarekh, C.; Kent-Bryant, J.; Keselman, G.; Mitidis, A.

    2016-09-01

    A space operations tradecraft consisting of detect-track-characterize-catalog is insufficient for maintaining Space Situational Awareness (SSA) as space becomes increasingly congested and contested. In this paper, we apply analytical methodology from the Geospatial-Intelligence (GEOINT) community to a key challenge in SSA: predicting where and when a satellite may maneuver in the future. We developed a machine learning approach to probabilistically characterize Patterns of Life (PoL) for geosynchronous (GEO) satellites. PoL are repeatable, predictable behaviors that an object exhibits within a context and is driven by spatio-temporal, relational, environmental and physical constraints. An example of PoL are station-keeping maneuvers in GEO which become generally predictable as the satellite re-positions itself to account for orbital perturbations. In an earlier publication, we demonstrated the ability to probabilistically predict maneuvers of the Galaxy 15 (NORAD ID: 28884) satellite with high confidence eight days in advance of the actual maneuver. Additionally, we were able to detect deviations from expected PoL within hours of the predicted maneuver [6]. This was done with a custom unsupervised machine learning algorithm, the Interval Similarity Model (ISM), which learns repeating intervals of maneuver patterns from unlabeled historical observations and then predicts future maneuvers. In this paper, we introduce a supervised machine learning algorithm that works in conjunction with the ISM to produce a probabilistic distribution of when future maneuvers will occur. The supervised approach uses a Support Vector Machine (SVM) to process the orbit state whereas the ISM processes the temporal intervals between maneuvers and the physics-based characteristics of the maneuvers. This multiple model approach capitalizes on the mathematical strengths of each respective algorithm while incorporating multiple features and inputs. Initial findings indicate that the combined

  10. 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...

  11. [Internal carotid artery dissection after Heimlich maneuver].

    Science.gov (United States)

    Rakotoharinandrasana, H; Petit, E; Dumas, P; Vandermarcq, P; Gil, R; Neau, J-Ph

    2003-01-01

    We report a case of cervical artery dissection following a Heimlich maneuver. Cervical artery dissections are at the present time well known and are sometimes associated with trivial traumas. However, to our knowledge, this complication of such maneuver was never reported in the literature. Pathophysiological mechanisms are discussed.

  12. Tactical Maneuvering Using Immunized Sequence Selection

    Science.gov (United States)

    Kaneshige, John; KrishnaKumar, K.; Shung, Felix

    2003-01-01

    This paper describes a tactical maneuvering system that uses an artificial immune system based approach for selecting maneuver sequences. This approach combines the problem solving abilities of genetic algorithms with the memory retention characteristics of an immune system. Of significant importance here is the fact that the tactical maneuvering system can make time-critical decisions to accomplish near-term objectives within a dynamic environment. These objectives can be received from a human operator, autonomous executive, or various flight planning specialists. Simulation tests were performed using a high performance military aircraft model. Results demonstrate the potential of using immunized sequence selection in order to accomplish tactical maneuvering objectives ranging from flying to a location while avoiding unforeseen obstacles, to performing relative positioning in support of air combat maneuvering.

  13. Aerodynamic maneuvering hypersonic flight mechanics

    Science.gov (United States)

    Desautel, Dick

    1988-01-01

    The emergence of current high-interest mission involving aeromaneuvering hypersonic flight has given rise to the corresponding need for preliminary design and performance analyses of such vehicles. This need in turn has motivated efforts to develop simplified analytical and computational methods for parametric analysis of maneuvering hypersonic flight under conditions appropriate to the mission involved. The effort included a review of different formulations of the general equations of motion, their associated coordinate frames, various simplifications of the equations, and previously achieved analytical solutions. This study sought to both extend previous solution methods and to develop new ones. In addition, evaluation of the literature and developing a systematic perspective on the knowledge it represents proved to be a major portion of the effort.

  14. Valsalva maneuver: shortest optimal expiratory strain duration

    Directory of Open Access Journals (Sweden)

    Ramesh K. Khurana, Md

    2011-07-01

    Full Text Available Purpose : To quantitate the level of difficulty and determine consistency of hemodynamic responses with various expiratory strain (ES durations. Methods : Thirty-four healthy subjects performed the Valsalva maneuver (VM with an ES duration of 10, 12, and 15 seconds in random order. Level of difficulty after each trial was rated 1 to 10, with 10 being the most difficult. Blood pressure and heart rate (HR were recorded continuously and non-invasively. Parameters studied were Valsalva ratio (VR, early phase II (IIE, late phase II (IIL, tachycardia latency (TL, bradycardia latency (BL, and overshoot latency (OV-L. Consistency of responses was calculated. Results : Difficulty increased significantly with increased ES duration: 5.1±0.1 (mean±SEM at 10 seconds, 5.9±0.1 at 12 seconds, and 6.8±0.1 at 15 seconds (p<0.001. Phase IIE, TL, BL, OV-L, and VR response did not differ statistically with increasing ES durations, and there were no differences in variability. Phase IIL response increased significantly with increasing ES duration. Phase IIL was poorly delineated in 14 of 102 trials with 10 seconds ES duration. Conclusions : ES duration of 10 seconds created a low level of difficulty in healthy individuals. This strain duration produced consistent hemodynamic response for all parameters tested except IIL phase. The absence of IIL phase with 10 seconds ES should not be interpreted as an indicator of sympathetic vasoconstrictor failure.

  15. Computation of flow around maneuvering submerged bodies

    Science.gov (United States)

    Govindan, T. R.; Briley, W. R.; Levy, R.

    1988-10-01

    Generalized primary/secondary flow equations and a spatial-marching solution algorithm have been used to develop a procedure to compute the three-dimensional viscous flow around a submerged body in maneuver. The primary/secondary flow equations are an approximation to the Navier-Stokes equations for flows in which a primary flow direction can be identified. Important elements of the approximation are a locally specified primary flow direction and a decomposition of the secondary velocity field to identify a small velocity vector for approximations. No approximations are introduced for pressure in this approach. The primary/secondary flow equations are a well-posed initial-value problem in a spatial coordinate nominally aligned with the primary flow direction and are solved by a sequentially decoupled implicit algorithm. The procedure provides an order to two orders-of-magnitude run time advantage over solution of the Navier-Stokes equations. Results are presented for the flow past an unappended submarine hull in drift at a Reynolds number of 16 million and incidence of 20 degrees. These results are consistent with experimental observations and provide a means to compute the complex three-dimensional viscous flow field economically.

  16. Pressão expiratória positiva nas vias aéreas não reproduz as respostas de frequência cardíaca à manobra de Valsalva em homens jovens saudáveis Expiratory positive airway pressure does not reproduce heart rate responses to Valsalva maneuver in healthy young men

    Directory of Open Access Journals (Sweden)

    Isabella Gracindo Pissinato

    2012-06-01

    Full Text Available A pressão expiratória positiva nas vias aéreas (EPAP é um recurso terapêutico que compreende uma inspiração seguida de expiração contra resistência. Sua aplicação promove ajustes no sistema cardiovascular, de maneira similar ao observado durante a manobra de Valsalva (MV. O objetivo deste estudo foi analisar a resposta da frequência cardíaca (FC à MV e às diferentes formas de aplicação de EPAP a fim de identificar se e em qual condição esta técnica reproduz a resposta da FC observada na MV, em homens jovens aparentemente saudáveis. Foram estudados 10 sujeitos (24±3 anos; 25±3 kg/m² que realizaram os procedimentos de MV e EPAP, aleatoriamente em dias diferentes. Na MV o esforço expiratório foi sustentado por 15 s (pressão oral de 40 mmHg [53,4 cmH2O]. Empregou-se duas técnicas de EPAP (isolada e terapêutica contra 3 níveis de pressão (10, 15 e 20 cmH2O, aplicados aleatoriamente. As manobras foram repetidas três vezes com intervalo de cinco minutos. Considerou-se o maior valor de variação da FC (DFC de cada manobra para análise. Empregou-se o teste Shapiro-Wilk para verificar a distribuição dos dados e ANOVA para medidas repetidas, com post-hoc de Fisher, considerando-se αThe expiratory positive airway pressure (EPAP is a therapeutic resource that comprises an inspiration followed by expiration against resistance. During its application there were adjustments in the cardiovascular system, similar to those observed during the Valsalva maneuver (VM. The aim of this study was to analyze the heart rate (HR response to VM and to different ways of EPAP application to identify if and in which condition this technique reproduces the HR response observed in the VM, in apparently healthy young men. Ten subjects (24±3 years, 25±3 kg/m² performed randomly the VM and EPAP procedures on different days. The expiratory effort in VM was sustained for 15 s (oral pressure of 40 mmHg [53.4cm H2O]. Two EPAP techniques were

  17. Modeling Pathological Hemodynamic Responses to the Valsalva Maneuver.

    Science.gov (United States)

    Pstras, Leszek; Thomaseth, Karl; Waniewski, Jacek; Balzani, Italo; Bellavere, Federico

    2017-06-01

    The Valsalva maneuver (VM) consisting in a forced expiration against closed airways is one of the most popular clinical tests of the autonomic nervous system function. When properly performed by a healthy subject, it features four characteristic phases of arterial blood pressure (BP) and heart rate (HR) variations, based on the magnitude of which the autonomic function may be assessed qualitatively and quantitatively. In patients with some disorders or in healthy patients subject to specific conditions, the pattern of BP and HR changes during the execution of the Valsalva maneuver may, however, differ from the typical sinusoidal-like pattern. Several types of such abnormal responses are well known and correspond to specific physiological conditions. In this paper, we use our earlier mathematical model of the cardiovascular response to the Valsalva maneuver to show that such pathological responses may be simulated by changing individual model parameters with a clear physiological meaning. The simulation results confirm the adaptability of our model and its usefulness for diagnostic or educational purposes.

  18. Using the Heimlich maneuver to save near-drowning victims.

    Science.gov (United States)

    Heimlich, H J; Patrick, E A

    1988-08-01

    Flooding of the lungs occurs routinely in drowning victims. The cause of death in 90% of them is hypoxemia caused by water in the lungs. Mouth-to-mouth ventilation is ineffective until the water is removed. The Heimlich maneuver expels aspirated water, vomitus, debris, and other foreign matter. In treating near-drowning victims, place the victim in the supine position with head turned to the side and perform the Heimlich maneuver to evacuate water from the lungs, unless you know water is not in the respiratory tract. The Heimlich maneuver is a form of artificial respiration. It elevates the diaphragm, increasing intrathoracic pressure and compressing the lungs, and should be performed intermittently until all water is expelled. It is an especially useful technique because fear of contagion sometimes deters rescuers from using mouth-to-mouth ventilation . Further treatment has not been necessary in most instances. If the victim does not recover after water ceases to flow from the mouth, ventilation techniques, cardiopulmonary resuscitation, and other measures as indicated should be used.

  19. Cassini Solstice Mission Maneuver Experience: Year One

    Science.gov (United States)

    Wagner, Sean V.; Arrieta, Juan; Ballard, Christopher G.; Hahn, Yungsun; Stumpf, Paul W.; Valerino, Powtawche N.

    2011-01-01

    The Cassini-Huygens spacecraft began its four-year Prime Mission to study Saturn's system in July 2004. Two tour extensions followed: a two-year Equinox Mission beginning in July 2008 and a seven-year Solstice Mission starting in September 2010. This paper highlights Cassini maneuver activities from June 2010 through June 2011, covering the transition from the Equinox to Solstice Mission. This interval included 38 scheduled maneuvers, nine targeted Titan flybys, three targeted Enceladus flybys, and one close Rhea flyby. In addition, beyond the demanding nominal navigation schedule, numerous unforeseen challenges further complicated maneuver operations. These challenges will be discussed in detail.

  20. Gastric rupture after the Heimlich maneuver.

    Science.gov (United States)

    Bintz, M; Cogbill, T H

    1996-01-01

    Since 1975, the Heimlich maneuver has been widely applied to relieve upper airway obstruction caused by aspirated material. Life-threatening complications have been documented following this simple procedure. We report two cases of gastric rupture after use of the Heimlich maneuver. Both patients experienced pulmonary and abdominal symptoms. The diagnosis was confirmed in each case by the demonstration of free intraperitoneal air on an upright chest roentgenogram. Full-thickness gastric rupture along the lesser curvature of the stomach was repaired in both patients; one patient died. Abdominal pain or persistent abdominal distention despite nasogastric suction after the Heimlich maneuver should prompt evaluation for possible gastric rupture.

  1. Development Of Maneuvering Autopilot For Flight Tests

    Science.gov (United States)

    Menon, P. K. A.; Walker, R. A.

    1992-01-01

    Report describes recent efforts to develop automatic control system operating under supervision of pilot and making airplane follow prescribed trajectories during flight tests. Report represents additional progress on this project. Gives background information on technology of control of test-flight trajectories; presents mathematical models of airframe, engine and command-augmentation system; focuses on mathematical modeling of maneuvers; addresses design of autopilots for maneuvers; discusses numerical simulation and evaluation of results of simulation of eight maneuvers under control of simulated autopilot; and presents summary and discussion of future work.

  2. Anterior Displacement of Lamina Cribrosa during Valsalva Maneuver in Young Healthy Eyes.

    Directory of Open Access Journals (Sweden)

    Yong Woo Kim

    Full Text Available To investigate lamina cribrosa (LC displacement during the Valsalva maneuver in young healthy eyes using enhanced depth imaging (EDI spectral-domain optical coherence tomography (SD-OCT.Forty-eight eyes of 48 young healthy volunteers (age range: 20-34 years underwent intraocular pressure (IOP measurement by Goldmann applanation tonometry as well as Cirrus HD-OCT scans before and during the Valsalva maneuver. The optic nerve head (ONH parameters (average retinal nerve fiber layer thickness, rim area, disc area, average C/D ratio, vertical C/D ratio, cup volume, anterior LC depth (LCD, subfoveal and peripapillary choroidal thickness, and neural canal opening diameter were measured on compensated OCT and compared during Valsalva challenge. The subjects were asked to take a five-minute break after each Valsalva maneuver.During the Valsalva maneuver, the IOP significantly increased, from 12.7 ± 3.0 mmHg to 16.0 ± 3.2 mmHg (P 0.05.The Valsalva maneuver induced anterior displacement of the LC, but did not alter the choroidal thickness or ONH morphology. The data describe the positional characteristics of the LC in response to the Valsalva maneuver in young healthy eyes.

  3. Helicopter stability during aggressive maneuvers

    Science.gov (United States)

    Mohan, Ranjith

    The dissertation investigates helicopter trim and stability during level bank-angle and diving bank-angle turns. The level turn is moderate in that sufficient power is available to maintain level maneuver, and the diving turn is severe where the power deficit is overcome by the kinetic energy of descent. The investigation basically represents design conditions where the peak loading goes well beyond the steady thrust limit and the rotor experiences appreciable stall. The major objectives are: (1) to assess the sensitivity of the trim and stability predictions to the approximations in modeling stall, (2) to correlate the trim predictions with the UH-60A flight test data, and (3) to demonstrate the feasibility of routinely using the exact fast-Floquet periodic eigenvector method for mode identification in the stability analysis. The UH-60A modeling and analysis are performed using the comprehensive code RCAS (Army's Rotorcraft Comprehensive Analysis System). The trim and damping predictions are based on quasisteady stall, ONERA-Edlin (Equations Differentielles Lineaires) and Leishman-Beddoes dynamic stall models. From the correlation with the test data, the strengths and weaknesses of the trim predictions are presented.

  4. Synthetic Imaging Maneuver Optimization (SIMO) Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Aurora Flight Sciences (AFS), in collaboration with the MIT Space Systems Laboratory (MIT-SSL), proposed the Synthetic Imaging Maneuver Optimization (SIMO) program...

  5. Optimization of satellite constellation reconfiguration maneuvers

    Science.gov (United States)

    Appel, Leonid; Guelman, Moshe; Mishne, David

    2014-06-01

    Constellation satellites are required to perform orbital transfer maneuvers. Orbital transfer maneuvers, as opposed to orbital correction maneuvers, are seldom performed but require a substantial amount of propellant for each maneuver. The maneuvers are performed in order to obtain the desired constellation configuration that satisfies the coverage requirements. In most cases, the single-satellite position is immaterial; rather the relative position between constellation multiple-satellites is to be controlled. This work deals with the solution to the coupled optimization problem of multiple-satellite orbital transfer. The studied problem involves a coupled formulation of the terminal conditions of the satellites. The solution was achieved using functional optimization techniques by a combined algorithm. The combined algorithm is based on the First Order Gradient and Neighboring-Extremals Algorithms. An orbital transfer optimization tool was developed. This software has the ability to consider multiple satellites with coupled terminal conditions. A solution to the multiple-satellite orbital transfer optimization problem is presented. A comparison of this solution to the uncoupled case is presented in order to review the benefits of using this approach. It is concluded that the coupled transfer maneuver solution approach is more computationally efficient and more accurate. Numerical solutions for a number of representative cases are presented.

  6. The effect of a trunk release maneuver on Peak Pressure Index, trunk displacement and perceived discomfort in older adults seated in a High Fowler's position: a randomized controlled trial.

    Science.gov (United States)

    Best, Krista L; Desharnais, Guylaine; Boily, Jeanette; Miller, William C; Camp, Pat G

    2012-11-16

    Pressure ulcers pose significant negative individual consequences and financial burden on the healthcare system. Prolonged sitting in High Fowler's position (HF) is common clinical practice for older adults who spend extended periods of time in bed. While HF aids in digestion and respiration, being placed in a HF may increase perceived discomfort and risk of pressure ulcers due to increased pressure magnitude at the sacral and gluteal regions. It is likely that shearing forces could also contribute to risk of pressure ulcers in HF. The purpose of this study was to evaluate the effect of a low-tech and time-efficient Trunk Release Manuever (TRM) on sacral and gluteal pressure, trunk displacement and perceived discomfort in ambulatory older adults. A randomized controlled trial was used. We recruited community-living adults who were 60 years of age and older using posters, newspaper advertisements and word-of-mouth. Participants were randomly allocated to either the intervention or control group. The intervention group (n = 59) received the TRM, while the control group (n = 58) maintained the standard HF position. The TRM group had significantly lower mean (SD) PPI values post-intervention compared to the control group, 59.6 (30.7) mmHg and 79.9 (36.5) mmHg respectively (p = 0.002). There was also a significant difference in trunk displacement between the TRM and control groups, +3.2 mm and -5.8 mm respectively (p = 0.005). There were no significant differences in perceived discomfort between the groups. The TRM was effective for reducing pressure in the sacral and gluteal regions and for releasing the trunk at the point of contact between the skin and the support surface, but did not have an effect on perceived discomfort. The TRM is a simple method of repositioning which may have important clinical application for the prevention of pressure ulcers that may occur as a result of HF.

  7. Gastric rupture after Heimlich maneuver and cardiopulmonary resuscitation.

    Science.gov (United States)

    Tung, P H; Law, S; Chu, K M; Law, W L; Wong, J

    2001-01-01

    Choking is a common emergency problem. The Heimlich maneuver is unquestionably effective in relieving airway obstruction. Serious and life-threatening complications may arise, however, if the maneuver is applied incorrectly. Two cases of gastric rupture after Heimlich maneuver are reported. Lay public, paramedics and the medical professionals should be educated with the correct technique of Heimlich maneuver and its potential complications. All patients receiving Heimlich maneuver should be examined by an experienced physician.

  8. Nursing experience of the application of fundal pressing midwifery%应用宫底按压助产法的护理体会

    Institute of Scientific and Technical Information of China (English)

    刘玲妹

    2016-01-01

    Objective:To investigate the efficacy of fundal pressing midwifery for vaginal delivery.Methods:62 cases of pregnant women were selected.They were randomly divided into the observation group and the control group with 31 cases in each.The control group received conventional mode of delivery,and the observation group received the uterine bottom pressing midwifery and accept the high quality nursing intervention in childbirth.Results:The second stage of labor time,maternal satisfaction rate, perineal laceration, neonatal asphyxia rate of the observation group were better than those of the control group(P<0.05). Conclusion:The implementation of high quality nursing combined with fundus pressing midwifery can shorten the delivery time, reduce postpartum complications and the rate of neonatal asphyxia,and improve the nursing satisfaction rate.%目的:探讨宮底按压助产法用于阴道分娩的效果。方法:收治产妇62例,随机分为观察组和对照组各31例,对照组实施常规分娩方式,观察组在实施宫底按压助产法的同时接受优质护理干预分娩。结果:观察组第二产程分娩时间、产妇满意率、会阴撕裂率、新生儿窒息情况优于对照组(P<0.05)。结论:实施优质护理措施联合宫底按压助产法,可缩短分娩时间,减少产后并发症及新生儿窒息率,提高护理满意率。

  9. The effect of a trunk release maneuver on Peak Pressure Index, trunk displacement and perceived discomfort in older adults seated in a high Fowler’s position: a randomized controlled trial

    Directory of Open Access Journals (Sweden)

    Best Krista L

    2012-11-01

    Full Text Available Abstract Background Pressure ulcers pose significant negative individual consequences and financial burden on the healthcare system. Prolonged sitting in High Fowler’s position (HF is common clinical practice for older adults who spend extended periods of time in bed. While HF aids in digestion and respiration, being placed in a HF may increase perceived discomfort and risk of pressure ulcers due to increased pressure magnitude at the sacral and gluteal regions. It is likely that shearing forces could also contribute to risk of pressure ulcers in HF. The purpose of this study was to evaluate the effect of a low-tech and time-efficient Trunk Release Manuever (TRM on sacral and gluteal pressure, trunk displacement and perceived discomfort in ambulatory older adults. Method A randomized controlled trial was used. We recruited community-living adults who were 60 years of age and older using posters, newspaper advertisements and word-of-mouth. Participants were randomly allocated to either the intervention or control group. The intervention group (n = 59 received the TRM, while the control group (n = 58 maintained the standard HF position. Results The TRM group had significantly lower mean (SD PPI values post-intervention compared to the control group, 59.6 (30.7 mmHg and 79.9 (36.5 mmHg respectively (p = 0.002. There was also a significant difference in trunk displacement between the TRM and control groups, +3.2 mm and −5.8 mm respectively (p = 0.005. There were no significant differences in perceived discomfort between the groups. Conclusion The TRM was effective for reducing pressure in the sacral and gluteal regions and for releasing the trunk at the point of contact between the skin and the support surface, but did not have an effect on perceived discomfort. The TRM is a simple method of repositioning which may have important clinical application for the prevention of pressure ulcers that may occur as a result of HF.

  10. Hemodynamic responses during and after multiple sets of stretching exercises performed with and without the Valsalva maneuver

    Directory of Open Access Journals (Sweden)

    Tainah P. Lima

    2015-05-01

    Full Text Available OBJECTIVE: This study investigated the acute hemodynamic responses to multiple sets of passive stretching exercises performed with and without the Valsalva maneuver. METHODS: Fifteen healthy men aged 21 to 29 years with poor flexibility performed stretching protocols comprising 10 sets of maximal passive unilateral hip flexion, sustained for 30 seconds with equal intervals between sets. Protocols without and with the Valsalva maneuver were applied in a random counterbalanced order, separated by 48-hour intervals. Hemodynamic responses were measured by photoplethysmography pre-exercise, during the stretching sets, and post-exercise. RESULTS: The effects of stretching sets on systolic and diastolic blood pressure were cumulative until the fourth set in protocols performed with and without the Valsalva maneuver. The heart rate and rate pressure product increased in both protocols, but no additive effect was observed due to the number of sets. Hemodynamic responses were always higher when stretching was performed with the Valsalva maneuver, causing an additional elevation in the rate pressure product. CONCLUSIONS: Multiple sets of unilateral hip flexion stretching significantly increased blood pressure, heart rate, and rate pressure product values. A cumulative effect of the number of sets occurred only for systolic and diastolic blood pressure, at least in the initial sets of the stretching protocols. The performance of the Valsalva maneuver intensified all hemodynamic responses, which resulted in significant increases in cardiac work during stretching exercises.

  11. Acute effects of physiotherapeutic respiratory maneuvers in critically ill patients with craniocerebral trauma

    Directory of Open Access Journals (Sweden)

    Manoel Luiz de Cerqueira Neto

    2013-09-01

    Full Text Available OBJECTIVE: To evaluate the effects of physiotherapeutic respiratory maneuvers on cerebral and cardiovascular hemodynamics and blood gas variables. METHOD: A descriptive, longitudinal, prospective, nonrandomized clinical trial that included 20 critical patients with severe craniocerebral trauma who were receiving mechanical ventilation and who were admitted to the intensive care unit. Each patient was subjected to the physiotherapeutic maneuvers of vibrocompression and increased manual expiratory flow (5 minutes on each hemithorax, along with subsequent airway suctioning with prior instillation of saline solution, hyperinflation and hyperoxygenation. Variables related to cardiovascular and cerebral hemodynamics and blood gas variables were recorded after each vibrocompression, increased manual expiratory flow and airway suctioning maneuver and 10 minutes after the end of airway suctioning. RESULTS: The hemodynamic and blood gas variables were maintained during vibrocompression and increased manual expiratory flow maneuvers; however, there were increases in mean arterial pressure, intracranial pressure, heart rate, pulmonary arterial pressure and pulmonary capillary pressure during airway suctioning. All of the values returned to baseline 10 minutes after the end of airway suctioning. CONCLUSION: Respiratory physiotherapy can be safely performed on patients with severe craniocerebral trauma. Additional caution must be taken when performing airway suctioning because this technique alters cerebral and cardiovascular hemodynamics, even in sedated and paralyzed patients.

  12. Cassini's Maneuver Automation Software (MAS) Process: How to Successfully Command 200 Navigation Maneuvers

    Science.gov (United States)

    Yang, Genevie Velarde; Mohr, David; Kirby, Charles E.

    2008-01-01

    To keep Cassini on its complex trajectory, more than 200 orbit trim maneuvers (OTMs) have been planned from July 2004 to July 2010. With only a few days between many of these OTMs, the operations process of planning and executing the necessary commands had to be automated. The resulting Maneuver Automation Software (MAS) process minimizes the workforce required for, and maximizes the efficiency of, the maneuver design and uplink activities. The MAS process is a well-organized and logically constructed interface between Cassini's Navigation (NAV), Spacecraft Operations (SCO), and Ground Software teams. Upon delivery of an orbit determination (OD) from NAV, the MAS process can generate a maneuver design and all related uplink and verification products within 30 minutes. To date, all 112 OTMs executed by the Cassini spacecraft have been successful. MAS was even used to successfully design and execute a maneuver while the spacecraft was in safe mode.

  13. Cassini's Maneuver Automation Software (MAS) Process: How to Successfully Command 200 Navigation Maneuvers

    Science.gov (United States)

    Yang, Genevie Velarde; Mohr, David; Kirby, Charles E.

    2008-01-01

    To keep Cassini on its complex trajectory, more than 200 orbit trim maneuvers (OTMs) have been planned from July 2004 to July 2010. With only a few days between many of these OTMs, the operations process of planning and executing the necessary commands had to be automated. The resulting Maneuver Automation Software (MAS) process minimizes the workforce required for, and maximizes the efficiency of, the maneuver design and uplink activities. The MAS process is a well-organized and logically constructed interface between Cassini's Navigation (NAV), Spacecraft Operations (SCO), and Ground Software teams. Upon delivery of an orbit determination (OD) from NAV, the MAS process can generate a maneuver design and all related uplink and verification products within 30 minutes. To date, all 112 OTMs executed by the Cassini spacecraft have been successful. MAS was even used to successfully design and execute a maneuver while the spacecraft was in safe mode.

  14. Partitioning kinetic energy during freewheeling wheelchair maneuvers.

    Science.gov (United States)

    Medola, Fausto O; Dao, Phuc V; Caspall, Jayme J; Sprigle, Stephen

    2014-03-01

    This paper describes a systematic method to partition the kinetic energy (KE) of a free-wheeling wheelchair. An ultralightweight rigid frame wheelchair was instrumented with two axle-mounted encoders and data acquisition equipment to accurately measure the velocity of the drive wheels. A mathematical model was created combining physical specifications and geometry of the wheelchair and its components. Two able-bodied subjects propelled the wheelchair over four courses that involved straight and turning maneuvers at differing speeds. The KE of the wheelchair was divided into three components: translational, rotational, and turning energy. This technique was sensitive to the changing contributions of the three energy components across maneuvers. Translational energy represented the major component of total KE in all maneuvers except a zero radius turn in which turning energy was dominant. Both translational and rotational energies are directly related to wheelchair speed. Partitioning KE offers a useful means of investigating the dynamics of a moving wheelchair. The described technique permits analysis of KE imparted to the wheelchair during maneuvers involving changes in speed and direction, which are most representative of mobility in everyday life. This technique can be used to study the effort required to maneuver different types and configurations of wheelchairs.

  15. Efeitos da manobra de hiperinsuflação manual associada à pressão positiva expiratória final em pacientes submetidos à cirurgia de revascularização miocárdica Effects of manual hyperinflation maneuver associated with positive end expiratory pressure in patients within coronary artery bypass grafting

    Directory of Open Access Journals (Sweden)

    Laura Jurema dos Santos

    2010-03-01

    Full Text Available OBJETIVO: Verificar os efeitos da manobra de hiperinsuflação manual associada à pressão positiva expiratória final em pacientes submetidos à cirurgia de revascularização do miocárdio. MÉTODOS: Ensaio clínico randomizado realizado entre agosto de 2007 e julho de 2008 na unidade de terapia intensiva do Hospital Luterano (ULBRA. Os pacientes foram divididos em grupo intervenção, no qual foi aplicada a manobra de hiperinsuflação manual associada à pressão positiva expiratória final, e grupo controle. As variáveis ventilatórias foram mensuradas em dois momentos: pré-manobra e pós-manobra. Foram utilizados os testes t de Student para amostras independentes e pareadas, bem como os testes exato de Fisher e o qui-quadrado de McNemar. RESULTADOS: Foram incluídos 18 pacientes durante o período de estudo, com idade média de 64±11 anos, sendo que houve predomínio do sexo feminino (55,6%. O volume corrente inspirado foi de 594± 112 ml no grupo intervenção e 487± 51 ml no grupo controle (p=0,024 e o volume corrente expirado de 598± 105 ml no grupo intervenção e 490± 58 ml no grupo controle (p=0,02. A média da complacência pulmonar estática no grupo intervenção pré-manobra foi de 41,6± 12,1 ml/cmH2O e pós-manobra de 47,4± 16,6 ml/cmH2O (p=0,03. Não houve diferença significativa entre os grupos nas seguintes variáveis: saturação periférica de oxigênio, pressão arterial de oxigênio, tempo de extubação e alterações radiológicas. CONCLUSÃO: Os resultados demonstram uma tendência da manobra de hiperinsuflação manual associada à pressão positiva expiratória final promover aumento dos volumes pulmonares e da complacência estática, entretanto estes achados necessitam confirmação.OBJECTIVE: To verify the effects of manual hyperinflation maneuver associated with positive end expiratory pressure in coronary artery bypass grafting patients. METHODS: This was a randomized trial, conducted from August 2007

  16. Close approach maneuvers around an oblate planet

    Science.gov (United States)

    Oliveira, G. M. C.; Prado, A. F. B. A.; Sanchez, D. M.

    2015-10-01

    There are many applications of the close approach maneuvers in astronautics, and several missions used this technique in the last decades. In the present work, those close approach maneuvers are revisited, but now considering that the spacecraft passes around an oblate planet. This fact changes the distribution of mass of the planet, increasing the mass in the region of the equator, so increasing the gravitational forces in the equatorial plane. Since the present study is limited to planar trajectories, there is an increase in the variation of energy given by the maneuver. The planet Jupiter is used as the body for the close approach, but the value of J2 is varied in a large range to simulate situations of other celestial bodies that have larger oblateness, but the same mass ratio. This is particularly true in recent discovered exoplanets, and this first study can help the study of the dynamics around those bodies.

  17. MANEUVERING TARGET TRACKING USING FUZZY COMPENSATOR

    Institute of Scientific and Technical Information of China (English)

    1998-01-01

    A new approach is provided to estimate the state of arbitrarily maneuvering target. In this approach a fuzzy compensator is used to tackle the uncertainty which results from the targets arbitrarily maneuvering. To design the observer of the nonlinear system, the fuzzy T-S model and the receding horizon control strategy are employed. Besides, the design depends on tracking the output error of the model. Compared with the technique used in other articles, the errors between the first estimated value and the true state value of the estimated variable are not strictly required. Numerical simulating results show that the proposed approach can estimate the states of the random maneuvering targets on-line so as to obtain the exact tracking of the target.

  18. Analysis of Maneuvering Flight of an Insect

    Institute of Scientific and Technical Information of China (English)

    Sunada S.; Wang H.; Zeng Lijiang; Kawachi K.

    2004-01-01

    Wing motion of a dragonfly in the maneuvering flight, which was measured by Wang et al. [1] was investigated. Equations of motion for a maneuvering flight of an insect were derived. These equations were applied for analyzing the maneuvering flight. Inertial forces and moments acting on a body and wings were estimated by using these equations and the measured motions of the body and the wings. The results indicated the following characteristics of this flight: (1) The phase difference in flapping motion between the two fore wings and two hind wings, and the phase difference between the flapping motion and the feathering motion of the four wings are equal to those in a steady forward flight with the maximum efficiency. (2)The camber change and the feathering motion were mainly controlled by muscles at the wing bases.

  19. 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.

  20. The Heimlich maneuver: breaking down the complications.

    Science.gov (United States)

    Chillag, Shawn; Krieg, Jake; Bhargava, Ranjana

    2010-02-01

    The very young and the very old are vulnerable to choking, and there are over 4000 choking-related deaths annually in the United States. Complications from the Heimlich maneuver (HM), as reported in infrequent case reports, predominantly relate to the elderly. It is doubtful that the denominator, numerator, appropriateness, expertise, and problems of maneuvers applied to choking victims will ever be known. This case report and literature review suggests that the treatment for acute elderly choking victims should be applied carefully and that esophageal food impaction, which should be rapidly distinguishable from choking, can have serious complications with application of the HM.

  1. Air Combat Maneuvering Expert System Trainer

    Science.gov (United States)

    1992-01-01

    AL-TP-1 991-0058....... AD-A246 459 AIR COMBAT MANEUVERING EXPERT A SYSTEM TRAINER R M S Robert J. BechtelTI T Markt Technology, incorporated ’T R...would have to be established for each segment of pilot training. The success of the air intercept trainer (AT), which shares some features with ACMEST

  2. Towboat Maneuvering Simulator. Volume III. Theoretical Description.

    Science.gov (United States)

    1979-05-01

    overshoot or :igzag maneuver;I - 1,2,3 .. . 6FL F- _’ Flan"ing rudder deflection rate a _ __ Steering rudder deflection rate Ship propulsion ratlol " elh...used with the equations are for the ship propulsion point (n - 1.0). The equations are written in terms of the complete barge flotillia towboat

  3. 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 vari

  4. 14 CFR 23.1507 - Operating maneuvering speed.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Operating maneuvering speed. 23.1507... Limitations and Information § 23.1507 Operating maneuvering speed. The maximum operating maneuvering speed, VO, must be established as an operating limitation. VO is a selected speed that is not greater than...

  5. Complications as a result of the Heimlich maneuver.

    Science.gov (United States)

    Lee, Steven L; Kim, Stephen S; Shekherdimian, Shant; Ledbetter, Daniel J

    2009-03-01

    The Heimlich maneuver is a well-described emergency procedure for management of foreign body airway obstructions. Although rare, complications of the Heimlich maneuver do exist. The purpose of this report is to review the known complications of this procedure. All reported complications published in English on Medline and PubMed were reviewed. Additionally, we present a rare case of acute pancreatitis with associated pseudocyst formation after the administration of the Heimlich maneuver on a healthy 3-year-old boy. Although life saving, the Heimlich maneuver may be associated with significant complications; thus, symptomatic patients after this maneuver should be thoroughly evaluated with appropriate laboratory and radiographic studies.

  6. Neural fuzzy inference network approach to maneuvering target tracking

    Institute of Scientific and Technical Information of China (English)

    韩红; 刘允才; 韩崇昭; 朱洪艳; 文戎

    2004-01-01

    In target tracking study, the fast target maneuver detecting and highly accurate tracking are very important.And it is difficult to be solved. For the radar/infrared image fused tracking system, a extend Kalman filter combines with a neural fuzzy inference network to be used in maneuvering target tracking. The features related to the target maneuver are extracted from radar, infrared measurements and outputs of tracking filter, and are sent into the neural fuzzy inference network as inputs firstly, and then the target's maneuver inputs are estimated, so that, the accurate tracking is achieved. The simulation results indicate that the new method is valuable for maneuvering target tracking.

  7. 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.

  8. Orbital Maneuvering Vehicle (OMV) plume and plume effects study

    Science.gov (United States)

    Smith, Sheldon D.

    1991-01-01

    The objective was to characterize the Orbital Maneuvering Vehicle (OMV) propulsion and attitude control system engine exhaust plumes and predict the resultant plume impingement pressure, heat loads, forces, and moments. Detailed description is provided of the OMV gaseous nitrogen (GN2) thruster exhaust plume flow field characteristics calculated with the RAMP2 snd SFPGEN computer codes. Brief descriptions are included of the two models, GN2 thruster characteristics and RAMP2 input data files. The RAMP2 flow field could be recalculated by other organizations using the information presented. The GN2 flow field can be readily used by other organizations who are interested in GN2 plume induced environments which require local flow field properties which can be supplied using the SFPGEN GN2 model.

  9. 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.

  10. 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.

  11. Orbital maneuvering vehicle guidance, navigation and control

    Science.gov (United States)

    Huber, W. G.; Finnell, W., III

    1985-01-01

    This paper describes the Orbital Maneuvering Vehicle (OMV) concept and its intended role. It recaps the past activities leading up to the current concept and summarizes the present status and plans. The various types of missions and operating modes required by the OMV are described as the basis of the guidance, navigation and control (GN&C) requirements. The general GN&C problem is outlined with potential hardware solutions.

  12. Identification and standardization of maneuvers based upon operational flight data

    Institute of Scientific and Technical Information of China (English)

    Wang Yongjun; Dong Jiang; Liu Xiaodong; Zhang Lixin

    2015-01-01

    To find a way of loads analysis from operational flight data for advanced aircraft, maneuver identification and standardization jobs are conducted in this paper. For thousands of sor-ties from one aircraft, after studying the flight attitude when performing actions, the start and end time of the maneuvers can be determined. According to those time points, various types of maneu-vers during the flight are extracted in the form of multi-parameters time histories. By analyzing the numerical range and curve shape of those parameters, a characteristic data library is established to model all types of maneuvers. Based on this library, a computer procedure using pattern-recogni-tion theory is programmed to conduct automatic maneuver identification with high accuracy. In that way, operational loads are classified according to maneuver type. For a group of identified maneuvers of the same type, after the processes of time normalization, trace shifting, as well as aver-aging and smoothing, the idealization standard time history of each maneuver type is established. Finally, the typical load statuses are determined successfully based on standard maneuvers. The proposed method of maneuver identification and standardization is able to derive operational loads effectively, and might be applied to monitoring loads in Individual Aircraft Tracking Program (IATP).

  13. The Heimlich maneuver. Best technique for saving any choking victim's life.

    Science.gov (United States)

    Heimlich, H J; Patrick, E A

    1990-05-01

    The American Red Cross (ARC) and the American Heart Association (AHA) advocated backslaps, chest thrusts, and abdominal thrusts for 10 years after the Heimlich maneuver was introduced in 1974. Even after the Surgeon General in 1985 declared these methods to be "hazardous, even lethal," the ARC and the AHA continue to recommend backslaps and chest thrusts for infants under 1 year of age. ARC and AHA instructional materials that advocate use of these methods have not been recalled, and the public has not been warned of the dangers. One cause of the confusion about backslaps is the flawed belief that gas pressure alone removes a foreign body. In addition, there is lack of understanding that, compared with the Heimlich maneuver, the backslap produces an insignificant amount of the energy required to expel an object from the airway. In fact, the energy produced by the backslap drives the foreign object in the wrong direction, toward the lungs, while the energy produced by the Heimlich maneuver drives the object away from the lungs, toward the mouth. Backslaps and chest thrusts should be publicly recalled as a treatment for choking infants before further deaths and injuries occur. The Heimlich maneuver is the best rescue technique for treating choking victims of all ages.

  14. Influence of the Valsalva maneuver on cardiac hemodynamics and right to left shunt in patients with patent foramen ovale

    Science.gov (United States)

    Zhao, Enfa; Zhang, Yafei; Kang, Chunmiao; Niu, Hua; Zhao, Jing; Sun, Lei; Liu, Baomin

    2017-03-01

    The purpose of this study was to investigate the influence of the Valsalva maneuver (VM) on cardiac hemodynamics in patients with patent foramen ovale (PFO). Sixty-five patients who were highly suspected to have PFO were included. The changes in E, A, E/A ratio of mitral valve blood flow, E, A, E/A ratio of tricuspid valve blood flow, left ventricular end-diastolic volume, area and right atrial area during the resting state and the strain phase of the Valsalva maneuver were observed by transthoracic echocardiography (TTE). Statistical analyses were performed using SPSS Version18.0. Compared to the resting state, mitral valve diastolic velocity E and A peaks at the strain phase of the Valsalva maneuver significantly decreased (P  0.05). PFO hemodynamic changes mainly occurred in the left ventricle when the Valsalva maneuver was performed. The Valsalva maneuver increased pressure in the chest, then pulmonary venous return was impeded, which resulted in left ventricular limited filling, and E and A peaks decreased. The pressure of the left ventricle and atrium was lower than that of the right side, which resulted in right-to-left shunt (RLS) through PFO.

  15. 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.

  16. Abdominal aortic thrombosis in association with an attempted Heimlich maneuver.

    Science.gov (United States)

    Roehm, E F; Twiest, M W; Williams, R C

    1983-03-04

    We report herein a case of an incorrectly applied Heimlich maneuver--to the best of our knowledge, the first reported fatal complication associated with a Heimlich maneuver, acute thrombosis of an abdominal aortic aneurysm, and the distal aorta. While the Heimlich maneuver is effective for the relief of foreign body-induced upper airway obstruction, increased efforts should be directed toward instructing the public in correctly recognizing and optimally treating airway obstruction.

  17. Optimum PN Guidance Law for Maneuvering Target

    Institute of Scientific and Technical Information of China (English)

    SUN Bao-cai; QI Zai-kang

    2007-01-01

    An optimum PN guidance law for maneuvering target is developed using optimal control theory. By estimating the target position and setting the cost function, the guidance law can be deduced even without knowing the missile lateral acceleration. Since the quadratic cost function can make a compromise between the miss distance andthe control constraint, the optimum guidance law obtained is more general. Also, introduced line of sight rate as the input, a practical form of this guidance law is derived. The simulation results show the effectiveness of the guidance laws.

  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. Cardiovascular responses to passive static flexibility exercises are influenced by the stretched muscle mass and the Valsalva maneuver

    OpenAIRE

    Paulo T. V. Farinatti; Pedro P. S Soares; Monteiro, Walace D.; Duarte,Antonio F. A; Viveiros de Castro, Luis A

    2011-01-01

    BACKGROUND: The respiratory pattern is often modified or even blocked during flexibility exercises, but little is known about the cardiovascular response to concomitant stretching and the Valsalva maneuver (VM) in healthy subjects. OBJECTIVES: This study evaluated the heart rate (HR), systolic blood pressure (SBP), and rate-pressure product (RPP) during and after large and small muscle group flexibility exercises performed simultaneously with the VM. METHODS: Asymptomatic volunteers (N  =  22...

  20. 14 CFR 25.331 - Symmetric maneuvering conditions.

    Science.gov (United States)

    2010-01-01

    ... determining elevator angles and chordwise load distribution in the maneuvering conditions of paragraphs (b.... (c) Pitch maneuver conditions. The conditions specified in paragraphs (c)(1) and (2) of this section must be investigated. The movement of the pitch control surfaces may be adjusted to take into account...

  1. 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.

  2. 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... Technical Operations § 25.282 Orbit raising maneuvers. A space station authorized to operate in the geostationary satellite orbit under this part is also authorized to transmit in connection with...

  3. 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...

  4. 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...

  5. 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.

  6. 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

  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. Dynamics of spacecraft control laboratory experiment (SCOLE) slew maneuvers

    Science.gov (United States)

    Kakad, Y. P.

    1987-01-01

    This is the first of two reports on the dynamics and control of slewing maneuvers of the NASA Spacecraft Control Laboratory Experiment (SCOLE). In this report, the dynamics of slewing maneuvers of SCOLE are developed in terms of an arbitrary maneuver about any given axis. The set of dynamical equations incorporate rigid-body slew maneuver and three-dimensional vibrations of the complete assembly comprising the rigid shuttle, the flexible beam, and the reflector with an offset mass. The analysis also includes kinematic nonlinearities of the entire assembly during the maneuver and the dynamics of the interaction between the rigid shuttle and the flexible appendage. The final set of dynamical equations obtained for slewing maneuvers is highly nonlinear and coupled in terms of the flexible modes and the rigid-body modes. The equations are further simplified and evaluated numerically to include the first ten flexible modes and the SCOLE data to yield a model for designing control systems to perform slew maneuvers.

  9. Impact of cerebral cardiopulmonary resuscitation maneuvers in a general hospital: prognostic factors and outcomes

    Directory of Open Access Journals (Sweden)

    Bartholomay Eduardo

    2003-01-01

    Full Text Available OBJECTIVE: To assess survival of patients undergoing cerebral cardiopulmonary resuscitation maneuvers and to identify prognostic factors for short-term survival. METHODS: Prospective study with patients undergoing cardiopulmonary resuscitation maneuvers. RESULTS: The study included 150 patients. Spontaneous circulation was re-established in 88 (58% patients, and 42 (28% were discharged from the hospital. The necessary number of patients treated to save 1 life in 12 months was 3.4. The presence of ventricular fibrillation or tachycardia (VF/VT as the initial rhythm, shorter times of cardiopulmonary resuscitation maneuvers and cardiopulmonary arrest, and greater values of mean blood pressure (BP prior to cardiopulmonary arrest were independent variables for re-establishment of spontaneous circulation and hospital discharge. The odds ratios for hospital discharge were as follows: 6.1 (95% confidence interval [CI] = 2.7-13.6, when the initial rhythm was VF/VT; 9.4 (95% CI = 4.1-21.3, when the time of cerebral cardiopulmonary resuscitation was 70 mmHg. CONCLUSION: The presence of VF/VT as the initial rhythm, shorter times of cerebral cardiopulmonary resuscitation and of cardiopulmonary arrest, and a greater value of BP prior to cardiopulmonary arrest were independent variables of better prognosis.

  10. Desaturation Maneuvers and Precise Orbit Determination for the BepiColombo Mission

    CERN Document Server

    Alessi, Elisa Maria; Milani, Andrea; Tommei, Giacomo

    2012-01-01

    The purpose of this work is the analysis of the consequences that desaturation maneuvers can have in the precise orbit determination corresponding to the Radio Science Experiment (MORE) of the BepiColombo mission to Mercury. This mission is an ESA/JAXA joint project with very challenging objectives regarding geodesy, geophysics and fundamental physics. In the neighborhood of Mercury, the s/c will experience strong solar radiation pressure torques; the s/c attitude is controlled by inertial wheels that after some time reach their maximum rotation state. Then they have to be slowed down by means of thruster pulses, inducing a residual acceleration on the s/c, with a desaturation (or off-loading) maneuver. In this paper, we will show how such maneuvers affect the orbit of the s/c and the radio science measurements and, also, how to include them in the orbit determination and parameter estimation procedure. The non linear least squares fit we consider is applied on a set of observational arcs separated by interva...

  11. 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.

  12. Traumatic rupture of the stomach after Heimlich maneuver.

    Science.gov (United States)

    van der Ham, A C; Lange, J F

    1990-01-01

    Fatal complications following the performance of the Heimlich maneuver have been reported. A 76-year-old woman presented to the emergency department with signs of respiratory distress, abdominal pain and distension one day after airway obstruction and subsequent resuscitation. Despite successful immediate laparotomy and repair of a ruptured stomach, she later succumbed to the sequelae of aspiration of gastric contents and dehiscence of the gastric tear. This is the 4th case of stomach rupture and the 7th reported fatal complication following the Heimlich maneuver. It is recommended that persons who undergo the Heimlich maneuver be examined and observed by a physician, as soon as possible, to rule out complications.

  13. Effects of electric stimulation of the hunger center in the lateral hypothalamus on slow electric activity and spike activity of fundal and antral stomach muscles in rabbits under conditions of hunger and satiation.

    Science.gov (United States)

    Kromin, A A; Zenina, O Yu

    2013-09-01

    In chronic experiments on rabbits, the effect of electric stimulation of the hunger center in the lateral hypothalamus on myoelectric activity of the fundal and antral parts of the stomach was studied under conditions of hunger and satiation in the absence of food. Stimulation of the lateral hypothalamus in rabbits subjected to 24-h food deprivation and in previously fed rabbits produced incessant seeking behavior, which was followed by reorganization of the structure of temporal organization of slow wave electric activity of muscles of the stomach body and antrum specific for hungry and satiated animals. Increased hunger motivation during electric stimulation of the lateral hypothalamus manifested in the structure of temporal organization of slow wave electric activity of the stomach body and antrum muscles in rabbits subjected to 24-h food deprivation in the replacement of bimodal distribution of slow wave periods to a trimodal type typical of 2-day deprivation, while transition from satiation to hunger caused by electric stimulation of the lateral hypothalamus was associated with a shift from monomodal distributions of slow wave periods to a bimodal type typical of 24-h deprivation. Reorganization of the structure of temporal organization of slow wave electric activity of the stomach body and antrum muscles during electric stimulation of the lateral hypothalamus was determined by descending inhibitory influences of food motivational excitation on activity of the myogenic pacemaker of the lesser curvature of the stomach.

  14. Road Friction Estimation under Complicated Maneuver Conditions for Active Yaw Control

    Institute of Scientific and Technical Information of China (English)

    LI Liang; LI Hongzhi; SONG Jian; YANG Cai; WU Hao

    2009-01-01

    Road friction coefficient is a key factor for the stability control of the vehicle dynamics in the critical conditions. Obviously the vehicle dynamics stability control systems, including the anti-lock brake system(ABS), the traction control system(TCS), and the active yaw control(AYC) system, need the accurate tire and road friction information. However, the simplified method based on the linear tire and vehicle model could not obtain the accurate road friction coefficient for the complicated maneuver of the vehicle. Because the active braking control mode of AYC is different from that of ABS, the road friction coefficient cannot be estimated only with the dynamics states of the tire. With the related dynamics states measured by the sensors of AYC, a comprehensive strategy of the road friction estimation for the active yaw control is brought forward with the sensor fusion technique. Firstly, the variations of the dynamics characteristics of vehicle and tire, and the stability control mode in the steering process are considered, and then the proper road friction estimation methods are brought forward according to the vehicle maneuver process. In the steering maneuver without braking, the comprehensive road friction from the four wheels may be estimated based on the multi-sensor signal fusion method. The estimated values of the road friction reflect the road friction characteristic. When the active brake involved, the road friction coefficient of the braked wheel may be estimated based on the brake pressure and tire forces, the estimated values reflect the road friction between the braked wheel and the road. So the optimal control of the wheel slip rate may be obtained according to the road friction coefficient. The methods proposed in the paper are integrated into the real time controller of AYC, which is matched onto the test vehicle. The ground tests validate the accuracy of the proposed method under the complicated maneuver conditions.

  15. Cooperative maneuver enabled UAV relative localization

    Science.gov (United States)

    Strader, Jared

    The ability to localize itself in an environment is essential for any autonomous vehicle. In applications involving multiple Unmanned Aerial Vehicles (UAVs) such as formation flight, surveillance, and mapping, the relative pose of each UAV provides vital information for multiple vehicles to coordinate effectively. The majority of cooperative localization tasks involving multiple UAVs assume the transformation between reference frames, but this information is not always provided in the absence of landmarks or a Global Positioning System (GPS). This thesis presents a method for estimating the relative pose of a pair of UAVs using range-only measurements. In this method, there is no prior information assumed about the relative pose of each UAV. Instead, the trajectories are constrained in order to leverage the circumstances in which the range-only measurements are obtained during flight. To augment this limited information, motion is used to construct a graph of the UAV trajectories using only distance measurements. Using the constructed graph, four potential solutions are derived for the relative pose, and a batch estimate is performed to obtain numerical estimates of each of the four solutions. Using the batch estimate, a cooperative maneuver can be performed in order to obtain a unique solution. The sensitivity to the trajectory and measurement noise are analyzed through a Monte Carlo analysis.

  16. Orbital Maneuvering Vehicle (OMV) remote servicing kit

    Science.gov (United States)

    Brown, Norman S.

    1988-01-01

    With the design and development of the Orbital Maneuvering Vehicle (OMV) progressing toward an early 1990 initial operating capability (IOC), a new era in remote space operations will evolve. The logical progression to OMV front end kits would make available in situ satellite servicing, repair, and consummables resupply to the satellite community. Several conceptual design study efforts are defining representative kits (propellant tanks, debris recovery, module servicers); additional focus must also be placed on an efficient combination module servicer and consummables resupply kit. A remote servicer kit of this type would be designed to perform many of the early maintenance/resupply tasks in both nominal and high inclination orbits. The kit would have the capability to exchange Orbital Replacement Units (ORUs), exchange propellant tanks, and/or connect fluid transfer umbilicals. Necessary transportation system functions/support could be provided by interfaces with the OMV, Shuttle (STS), or Expendable Launch Vehicle (ELV). Specific remote servicer kit designs, as well as ground and flight demonstrations of servicer technology are necessary to prepare for the potential overwhelming need. Ground test plans should adhere to the component/system/breadboard test philosophy to assure maximum capability of one-g testing. The flight demonstration(s) would most likely be a short duration, Shuttle-bay experiment to validate servicer components requiring a micro-g environment.

  17. Tongue-Driven Wheelchair Out-Maneuvers the Competition

    Science.gov (United States)

    ... 496-3500 Share Science Highlight: January 2, 2014 Tongue-Driven Wheelchair Out-Maneuvers the Competition Researchers funded ... Imaging and Bioengineering have demonstrated that their novel Tongue Drive System is superior to other assistive devices ...

  18. Pulsed Electrogasdynamic Thruster for Attitude Control and Orbit Maneuver Project

    Data.gov (United States)

    National Aeronautics and Space Administration — In the Phase I program we successfully demonstrated the feasibility of the Pulsed ElectroGasdynamic (PEG) thruster for attitude control and orbital maneuvering. In...

  19. Pulsed Electrogasdynamic Thruster for Attitude Control and Orbit Maneuver Project

    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...

  20. Convected transient analysis for large space structures maneuver and deployment

    Science.gov (United States)

    Housner, J.

    1984-01-01

    Convected-transient analysis techniques in the finite-element method are used to investigate the deployment and maneuver of large spacecraft structures with multiple-member flexible trusses and frames. Numerical results are presented for several sample problems.

  1. 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.

  2. Aqua/Aura Spring 2017 Inclination Adjust Maneuver Series

    Science.gov (United States)

    Noyes, Thomas; Stezelberger, Shane

    2017-01-01

    This will be presented at the International Earth Science Constellation Mission Operations Working Group meeting June 13-15, 2017 to discuss the AquaAura Spring 2017 Inclination Adjust Maneuver series.

  3. Maneuvering and Stability Performance of a Robotic Tuna

    National Research Council Canada - National Science Library

    Jamie M. Anderson; Narender K. Chhabra

    2002-01-01

    .... Built as a research platform with which to study the energetics and maneuvering performance of fish-swimming propulsion, the VCUUV is a self-contained free swimming research vehicle which follows...

  4. Braking news: link between crash severity and crash avoidance maneuvers

    DEFF Research Database (Denmark)

    Kaplan, Sigal; Prato, Carlo Giacomo

    2012-01-01

    crash avoidance maneuvers and crash severity, with differences emerging for different critical events. Moreover, results showed two trends:(a) most drivers failed to act when facing critical events and (b) drivers rarely performed crash avoidance maneuvers that were correlated with a higher probability...... of lower crash severity. These trends suggest that efforts to understand the mechanisms of reactions to different critical events should be made to improve in-vehicle warning systems, promote responsible driving behavior, and design forgiving infrastructures....

  5. Flight Simulator: Field of View Utilized in Performing Tactical Maneuvers.

    Science.gov (United States)

    1988-04-01

    were taken in the Simulator for Air-to-Air Combat (SAAC) and the Advanced Simulator for Pilot Training ( ASPT ). During the air-to-ground data collection...ground maneuvers were performed In the Advanced Simulator for Pilot Training ( ASPT ). The data collected provided an estimate of the FOV dimensions that a...tactical maneuvers were conducted in the AFHIRL ASPT located at Williams AFB. The ASPT had a fully instrumnted F-16 cockpit. The g-cueing was available

  6. Space Object Maneuver Detection Algorithms Using TLE Data

    Science.gov (United States)

    Pittelkau, M.

    2016-09-01

    An important aspect of Space Situational Awareness (SSA) is detection of deliberate and accidental orbit changes of space objects. Although space surveillance systems detect orbit maneuvers within their tracking algorithms, maneuver data are not readily disseminated for general use. However, two-line element (TLE) data is available and can be used to detect maneuvers of space objects. This work is an attempt to improve upon existing TLE-based maneuver detection algorithms. Three adaptive maneuver detection algorithms are developed and evaluated: The first is a fading-memory Kalman filter, which is equivalent to the sliding-window least-squares polynomial fit, but computationally more efficient and adaptive to the noise in the TLE data. The second algorithm is based on a sample cumulative distribution function (CDF) computed from a histogram of the magnitude-squared |V|2 of change-in-velocity vectors (V), which is computed from the TLE data. A maneuver detection threshold is computed from the median estimated from the CDF, or from the CDF and a specified probability of false alarm. The third algorithm is a median filter. The median filter is the simplest of a class of nonlinear filters called order statistics filters, which is within the theory of robust statistics. The output of the median filter is practically insensitive to outliers, or large maneuvers. The median of the |V|2 data is proportional to the variance of the V, so the variance is estimated from the output of the median filter. A maneuver is detected when the input data exceeds a constant times the estimated variance.

  7. 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...... offers at the GP and at municipal health centers. We find that TOF succeeded in maneuvering the agendas of the involved stakeholders by gaining the foothold, legitimacy, and GP motivation required to carry out the pilot implementation....

  8. Automated maneuver planning using a fuzzy logic algorithm

    Science.gov (United States)

    Conway, D.; Sperling, R.; Folta, D.; Richon, K.; Defazio, R.

    1994-01-01

    Spacecraft orbital control requires intensive interaction between the analyst and the system used to model the spacecraft trajectory. For orbits with right mission constraints and a large number of maneuvers, this interaction is difficult or expensive to accomplish in a timely manner. Some automation of maneuver planning can reduce these difficulties for maneuver-intensive missions. One approach to this automation is to use fuzzy logic in the control mechanism. Such a prototype system currently under development is discussed. The Tropical Rainfall Measurement Mission (TRMM) is one of several missions that could benefit from automated maneuver planning. TRMM is scheduled for launch in August 1997. The spacecraft is to be maintained in a 350-km circular orbit throughout the 3-year lifetime of the mission, with very small variations in this orbit allowed. Since solar maximum will occur as early as 1999, the solar activity during the TRMM mission will be increasing. The increasing solar activity will result in orbital maneuvers being performed as often as every other day. The results of automated maneuver planning for the TRMM mission will be presented to demonstrate the prototype of the fuzzy logic tool.

  9. Maintaining Aura's Orbit Requirements Under New Maneuver Operations

    Science.gov (United States)

    Johnson, Megan; Petersen, Jeremy D.

    2014-01-01

    The Earth Observing System (EOS) Afternoon Constellation consists of five member missions (GCOM-W1, Aqua, CALIPSO, CloudSat, and Aura), each of which maintain a frozen, sun-synchronous orbit with a 16-day repeating ground track that follows the Worldwide Reference System-2 (WRS-2). Under nominal science operations for Aura, the propulsion system is oriented such that the resultant thrust vector is aligned 13.493 degrees away from the velocity vector along the yaw axis. When performing orbit maintenance maneuvers, the spacecraft performs a yaw slew to align the thrust vector in the appropriate direction. A new Drag Make Up (DMU) maneuver operations scheme has been implemented for Aura alleviating the need for the 13.493 degree yaw slew. The focus of this investigation is to assess the impact that no-slew DMU maneuver operations will have on Auras Mean Local Time (MLT) which drives the required along track separation between Aura and the constellation members, as well as Auras frozen orbit properties, eccentricity and argument of perigee. Seven maneuver strategies were analyzed to determine the best operational approach. A mirror pole strategy, with maneuvers alternating at the North and South poles, was implemented operationally to minimize impact to the MLT. Additional analysis determined that the mirror pole strategy could be further modified to include frozen orbit maneuvers and thus maintain both MLT and the frozen orbit properties under no-slew operations

  10. Orbital maneuvering vehicle: A new capability

    Science.gov (United States)

    Huber, William G.

    The Orbital Maneuvering Vehicle (OMV) is a reusable, remotely controlled, free-flying vehicle being developed by NASA to perform a wide range of on-orbit missions and services in support of orbiting spacecraft. The OMV is capable of satellite delivery, retrieval, reboost, controlled deorbit, viewing, and subsatellite support missions. It is an important extension to the Space Transportation System and a key element of the Space Station operational scenario. The OMV can operate from the Shuttle, the Space Station, or can be space based. The OMV, being 15 ft in diameter and approximately 4 1/2 thick, mounts directly into the Shuttle payload bay. The vehicle design is highly modular, consisting of a Short Range Vehicle containing both hydrazine and cold gas RCS systems and all the avionics systems for electrical power, communications, data management, guidance, navigation, and 6-degree of freedom control. This vehicle weighs approximately 6,500 lb and can accomplish a high percentage of the project missions. For high delta-velocity missions, a bipropellant Propulsion Module (approximately 11,000lb) is added, giving a total weight of 17,500 lb. This module can be exchanged on orbit to effect bipropellant refueling. All the RCS and avionics modules are replaceable on orbit for maintenance. The OMV development program was initiated in 1986 with the selection of TRW as the prime contractor. The first flight is projected for 1991. An early planned use of OMV is to reboost the Hubble Space Telescope when required because of atmospheric drag. This paper contains details of the program status, vehicle description, and mission capabilities. The purpose of the paper is to acquaint the international space community with OMV capabilities and to stimulate the identification of new and unique mission applications.

  11. Valsalva's maneuver revisited: a quantitative method yielding insights into human autonomic control

    Science.gov (United States)

    Smith, M. L.; Beightol, L. A.; Fritsch-Yelle, J. M.; Ellenbogen, K. A.; Porter, T. R.; Eckberg, D. L.

    1996-01-01

    Seventeen healthy supine subjects performed graded Valsalva maneuvers. In four subjects, transesophageal echographic aortic cross-sectional areas decreased during and increased after straining. During the first seconds of straining, when aortic cross-sectional area was declining and peripheral arterial pressure was rising, peroneal sympathetic muscle neurons were nearly silent. Then, as aortic cross-sectional area and peripheral pressure both declined, sympathetic muscle nerve activity increased, in proportion to the intensity of straining. Poststraining arterial pressure elevations were proportional to preceding increases of sympathetic activity. Sympathetic inhibition after straining persisted much longer than arterial and right atrial pressure elevations. Similarly, R-R intervals changed in parallel with peripheral arterial pressure, until approximately 45 s after the onset of straining, when R-R intervals were greater and arterial pressures were smaller than prestraining levels. Our conclusions are as follows: opposing changes of carotid and aortic baroreceptor inputs reduce sympathetic muscle and increase vagal cardiac motor neuronal firing; parallel changes of barorsensory inputs provoke reciprocal changes of sympathetic and direct changes of vagal firing; and pressure transients lasting only seconds reset arterial pressure-sympathetic and -vagal response relations.

  12. 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

  13. Methods of rapid orbit forecasting after maneuvers for geostationary satellites

    Institute of Scientific and Technical Information of China (English)

    YANG XuHai; LI ZhiGang; FENG ChuGang; GUO Ji; SHI HuLi; AI GuoXiang; WU FengLei; QIAO RongChuan

    2009-01-01

    A geostationary (GEO) satellite may serve as a navigation satellite,but there is a problem that maneuvers frequently occur and the forces are difficult to model.Based on the technique of determining setellite orbits by transfer,a predicted orbit with high accuracy may be achieved by the method of statistical orbit determination in case of no maneuver force.The predicted orbit will soon be invalid after the maneuver starts,and it takes a long time to get a valid orbit after the maneuver ends.In order to improve ephemeris usability,the method of rapid orbit forecasting after maneuvers is studied.First,GEO satellite movement is analyzed in case of maneuvers based on the observation from the orbit measurement system by transfer.Then when a GEO satellite is in the free status just after maneuvers,the short arc observation is used to forecast the orbit.It is assumed that the common system bias and biases of each station are constant,which can be obtained from orbit determination with long arc observations.In this way,only 6 orbit elements would be solved by the method of statistical orbit determination,and the ephemeris with high accuracy may be soon obtained.Actual orbit forecasting with short arc observation for SlNOSAT-1 satellite shows that,with the tracking network available,the precision of the predicted orbit (RMS of O-C) can reach about 5 m with 15 min arc observation,and about 3 m with 30 min arc observation.

  14. Methods of rapid orbit forecasting after maneuvers for geostationary satellites

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    A geostationary(GEO) satellite may serve as a navigation satellite,but there is a problem that maneuvers frequently occur and the forces are difficult to model.Based on the technique of determining satellite orbits by transfer,a predicted orbit with high accuracy may be achieved by the method of statis-tical orbit determination in case of no maneuver force.The predicted orbit will soon be invalid after the maneuver starts,and it takes a long time to get a valid orbit after the maneuver ends.In order to improve ephemeris usability,the method of rapid orbit forecasting after maneuvers is studied.First,GEO satellite movement is analyzed in case of maneuvers based on the observation from the orbit meas-urement system by transfer.Then when a GEO satellite is in the free status just after maneuvers,the short arc observation is used to forecast the orbit.It is assumed that the common system bias and biases of each station are constant,which can be obtained from orbit determination with long arc observations.In this way,only 6 orbit elements would be solved by the method of statistical orbit determination,and the ephemeris with high accuracy may be soon obtained.Actual orbit forecasting with short arc observation for SINOSAT-1 satellite shows that,with the tracking network available,the precision of the predicted orbit(RMS of O-C) can reach about 5 m with 15 min arc observation,and about 3 m with 30 min arc observation.

  15. Orbital maneuvers around irregular shaped bodies

    Science.gov (United States)

    Venditti, Flaviane; Rocco, E. M.; Almeida Prado, A. B.

    2013-05-01

    Abstract (2,250 Maximum Characters): In the solar system there are many small bodies called asteroids. The large majority of these bodies are located in the asteroid belt, between the orbits of the planets Mars and Jupiter. The Near- Earth Objects, or NEOs, are objects with perihelion below 1.3AU, which include comets and asteroids. The NEOs are considered to have orbits passing close to the Earth’s orbit and, in the case of asteroids, are called Near-Earth Asteroids (NEAs). Among the NEAs there are bodies considered potentially hazardous asteroids (PHAs), whose minimum orbit intersection distance with Earth is 0.05AU and that have absolute magnitude (H) of 22, which would mean an asteroid of at least 110-240 meters, depending on its albedo. One of the major characteristic of the asteroids is the irregular shape, causing the dynamics of orbits around these bodies to be different from a spherical shaped one. The fact that an object is not spherical generates a perturbation on the gravitational field. The disturbing force can be determined considering the shape of the specific body. A satellite orbiting this body would suffer the effects of this perturbation, but knowing the disturbing force, it’s possible to correct and control the orbit according to the desired mission. The polyhedron method is a traditional way to model an asteroid by dividing the object into smaller parts. The data used on this work are composed by a combination of triangular faces. The total disturbing force is a sum of the force on each piece of the model. Therefore, after the simulations are obtained, it’s possible to apply the desired corrections of the perturbation using continuous low thrust in closed loop, making it possible to perform maneuvers near these bodies. One of the important applications of the study shown above is in the ASTER mission, that is under study by INPE and several other Brazilian academic institutions, which goal is to send a spacecraft to an asteroid and then

  16. Efficacy of the Valsalva Maneuver on Needle Projection Pain and Hemodynamic Responses During Spinal Puncture

    Directory of Open Access Journals (Sweden)

    Sussan Soltani Mohammadi, Amin Ghasemi Pajand, Gita Shoeibi

    2011-01-01

    Full Text Available This study evaluated the efficacy of the valsalva maneuver that can induce baroreceptor activation and nociception, on needle projection pain and hemodynamic responses associated with spinal puncture. Ninety adults, ASA physical status I and II undergoing elective surgeries were included. Patients were randomized into three equal groups. Group I (C: control; Group II (B: ball; pressed a rubber ball (attention-diverting method; Group III (V: valsalva; blew into sphygmomanometer tubing and hold the mercury column up to 30 mm Hg for a period of at least 20s. Spinal needle projection pain was graded using numeric rating scale (NRS: 1-10, where scales of 1-3 were rated as mild, 4-6 as moderate, and > 6 as severe. Blood pressure and heart rate, five minutes before the procedure, during the spinal puncture and first and third minutes after that, were also recorded. Significant reduction in NRS was observed in the valsalva group compared with the control and the ball groups (p=0.001. There were statistical but no significant clinical differences in mean arterial blood pressure and heart rates between the study groups (P=0.008 and P=0.016 respectively. In conclusion valsalva maneuver can decrease the skin puncture pain associated with spinal needle projection while observing hemodynamic changes.

  17. Proposal Intensity Adequacy of Expiratory Effort and Heart Rate Behavior During the Valsalva Maneuver in Preadolescents

    Directory of Open Access Journals (Sweden)

    Mario Augusto Paschoal

    2014-08-01

    Full Text Available Background: When performing the Valsalva maneuver (VM, adults and preadolescents produce the same expiratory resistance values. Objective: To analyze heart rate (HR in preadolescents performing VM, and propose a new method for selecting expiratory resistance. Method: The maximal expiratory pressure (MEP was measured in 45 sedentary children aged 9-12 years who subsequently performed VM for 20 s using an expiratory pressure of 60%, 70%, or 80% of MEP. HR was measured before, during, and after VM. These procedures were repeated 30 days later, and the data collected in the sessions (E1, E2 were analyzed and compared in periods before, during (0-10 and 10-20 s, and after VM using nonparametric tests. Results: All 45 participants adequately performed VM in E1 and E2 at 60% of MEP. However, only 38 (84.4% and 25 (55.5% of the participants performed the maneuver at 70% and 80% of MEP, respectively. The HR delta measured during 0-10 s and 10-20 s significantly increased as the expiratory effort increased, indicating an effective cardiac autonomic response during VM. However, our findings suggest the VM should not be performed at these intensities. Conclusion: HR increased with all effort intensities tested during VM. However, 60% of MEP was the only level of expiratory resistance that all participants could use to perform VM. Therefore, 60% of MEP may be the optimal expiratory resistance that should be used in clinical practice.

  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. Attitude-Control Algorithm for Minimizing Maneuver Execution Errors

    Science.gov (United States)

    Acikmese, Behcet

    2008-01-01

    A G-RAC attitude-control algorithm is used to minimize maneuver execution error in a spacecraft with a flexible appendage when said spacecraft must induce translational momentum by firing (in open loop) large thrusters along a desired direction for a given period of time. The controller is dynamic with two integrators and requires measurement of only the angular position and velocity of the spacecraft. The global stability of the closed-loop system is guaranteed without having access to the states describing the dynamics of the appendage and with severe saturation in the available torque. Spacecraft apply open-loop thruster firings to induce a desired translational momentum with an extended appendage. This control algorithm will assist this maneuver by stabilizing the attitude dynamics around a desired orientation, and consequently minimize the maneuver execution errors.

  20. Acute aortic thrombosis following incorrect application of the Heimlich maneuver.

    Science.gov (United States)

    Mack, Lloyd; Forbes, Thomas L; Harris, Kenneth A

    2002-01-01

    The Heimlich maneuver has been widely accepted as a safe and effective method of relieving life-threatening foreign-body upper airway obstruction. When applied incorrectly, however, it may result in direct trauma to the intraabdominal viscera. Only two cases of major aortic complications have been reported. Both have involved thrombosis of an abdominal aortic aneurysm. We report two further instances of aortic thrombotic complications due to the incorrect application of the Heimlich maneuver. The first case resulted in thrombosis of an abdominal aortic aneurysm. In the second case the abdominal thrusts caused dislodgement of thrombus from an atherosclerotic nonaneurysmal aorta, which resulted in thromboembolic occlusion of both lower extremities. In both cases, as with the two previously reported instances, massive reperfusion injury resulted, which eventually proved fatal. When applied incorrectly, the Heimlich maneuver may result in direct trauma to the abdominalaorta and is an unusual cause of acute aortic thrombosis.

  1. New therapeutic maneuver for anterior canal benign paroxysmal positional vertigo.

    Science.gov (United States)

    Yacovino, Dario A; Hain, Timothy C; Gualtieri, Francisco

    2009-11-01

    This article describes the clinical features of anterior semicircular canal benign paroxysmal positional vertigo (AC-BPPV) and a new therapeutic maneuver for its management. Our study was a retrospective review of cases from an ambulatory tertiary referral center. Thirteen patients afflicted with positional paroxysmal vertigo exhibiting brief positional down-beating nystagmus in positional tests (Dix-Hallpike and head-hanging position) were treated with a maneuver comprised of the following movements: Sequential head positioning beginning supine with head hanging 30 degrees dependent with respect to the body, then supine with head inclined 30 degrees forward, and ending sitting with head 30 degrees forward. All cases showed excellent therapeutic response to our repositioning procedure, i.e. relief of vertigo and elimination of nystagmus. The maneuver described is an option for AC-BPPV treatment.

  2. Autopilot Control Synthesis for Path Tracking Maneuvers of Underwater Vehicles

    Institute of Scientific and Technical Information of China (English)

    Sam-Sang YOU; Hyeung-Sik CHOI; Hwan-Seong KIM; Han-Il PARK

    2011-01-01

    This paper is concerned with the robust control synthesis of autonomous underwater vehicle (AUV) for general path following maneuvers. First, we present maneuvering kinematics and vehicle dynamics in a unified framework. Based on H loop-shaping procedure, the 2-DOF autopilot controller has been presented to enhance stability and path tracking.By use of model reduction, the high-order control system is reduced to one with reasonable order, and further the scaled low-order controller has been analyzed in both the frequency and the time domains. Finally, it is shown that the autopilot control system provides robust performance and stability against prescribed levels of uncertainty.

  3. 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.

  4. Variable structure guidance law for attacking surface maneuver targets

    Institute of Scientific and Technical Information of China (English)

    Han Yanhua; Xu Bo

    2008-01-01

    The characteristics of surface maneuver targets are analyzed and a 3-D relative motion model for missiles and targets is established. A variable structure guidance law is designed considering the characteristics of targets. In the guidance law, the distance between missiles and targets as well as the missile-target relative velocity are all substituted by estimation values. The estimation errors, the target's velocity, and the maneuver acceleration are all treated as bounded disturbance. The guidance law proposed can be implemented conveniently in engineering with little target information. The performance of the guidance system is analyzed theoretically and the numerical simulation result shows the effectiveness of the guidance law.

  5. Traumatic rupture of the stomach secondary to Heimlich maneuver.

    Science.gov (United States)

    Dupre, M W; Silva, E; Brotman, S

    1993-11-01

    The case of a 93-year-old man who received a Heimlich maneuver while choking is reported. After the procedure, the patient presented with abdominal pain and ultimately was found to have developed a gastric rupture. He was hospitalized for 66 days. Review of the literature showed that only four gastric perforations related to the Heimlich maneuver have been documented. Other complications have occurred. It is reasonable to perform the procedure as an alternative to asphyxiation, but emergency physicians must be aware of the fact that life-threatening complications may ensue.

  6. Active Control of Solar Array Dynamics During Spacecraft Maneuvers

    Science.gov (United States)

    Ross, Brant A.; Woo, Nelson; Kraft, Thomas G.; Blandino, Joseph R.

    2016-01-01

    Recent NASA mission plans require spacecraft to undergo potentially significant maneuvers (or dynamic loading events) with large solar arrays deployed. Therefore there is an increased need to understand and possibly control the nonlinear dynamics in the spacecraft system during such maneuvers. The development of a nonlinear controller is described. The utility of using a nonlinear controller to reduce forces and motion in a solar array wing during a loading event is demonstrated. The result is dramatic reductions in system forces and motion during a 10 second loading event. A motion curve derived from the simulation with the closed loop controller is used to obtain similar benefits with a simpler motion control approach.

  7. Tracking of Maneuvering Target in Glint Noise Environment

    Institute of Scientific and Technical Information of China (English)

    ZUODongguang; BIANShutan; HANChongzhao; ZHENGLin; ZHUHongyan

    2005-01-01

    This paper presents a tracking algorithm for maneuvering target in the presence of glint noise. In radar target tracking system, because of the random wandering of the target position, the measurement noise is clearly non-Gaussian distribution, called as glint noise, which has a considerable influence on conventional linear estimates. In this paper, the glint noise is modeled via the mixture of Gaussian distribution and Laplace distribution, and tackled with two model sets. The tracking algorithm for maneuvering target is derived detailedly when the model sets is interacting in the presence of glint noise. The Monte Carlo simulation results express its better performance in comparison with the IMM algorithm.

  8. Effects of repeated Valsalva maneuver straining on cardiac and vasoconstrictive baroreflex responses.

    Science.gov (United States)

    Convertino, Victor A; Ratliff, Duane A; Doerr, Donald F; Ludwig, David A; Muniz, Gary W; Benedetti, Erik; Chavarria, Jose; Koreen, Susan; Nguyen, Claude; Wang, Jeff

    2003-03-01

    We hypothesized that repeated respiratory straining maneuvers (repeated SM) designed to elevate arterial BPs (arterial baroreceptor loading) would acutely increase baroreflex responses. We tested this hypothesis by measuring cardiac baroreflex responses to carotid baroreceptor stimulation (neck pressures), and changes in heart rate and diastolic BP after reductions in BP induced by a 15-s Valsalva maneuver in 10 female and 10 male subjects at 1, 3, 6, and 24 h after performing repeated SM. Baroreflex responses were also measured in each subject at 1, 3, 6, and 24 h at the same time on a separate day without repeated SM (control) in a randomized, counter-balanced cross-over experimental design. There was no statistical difference in carotid-cardiac and peripheral vascular baroreflex responses measured across time following repeated SM compared with the control condition. Integrated cardiac baroreflex response (deltaHR/ deltaSBP) measured during performance of a Valsalva maneuver was increased by approximately 50% to 1.1 +/- 0.2 bpm x mm Hg(-1) at 1 h and 1.0 +/- 0.1 bpm x mm Hg(-1) at 3 h following repeated SM compared with the control condition (0.7 +/- 0.1 bpm x mm Hg(-1) at both 1 and 3 h, respectively). However, integrated cardiac baroreflex response after repeated SM returned to control levels at 6 and 24 h after training. These responses did not differ between men and women. Our results are consistent with the notion that arterial baroreceptor loading induced by repeated SM increased aortic, but not carotid, cardiac baroreflex responses for as long as 3 h after repeated SM. We conclude that repeated SM increases cardiac baroreflex responsiveness which may provide patients, astronauts, and high-performance aircraft pilots with protection from development of orthostatic hypotension.

  9. Acute thrombosis of abdominal aortic aneurysm subsequent to Heimlich maneuver: a case report.

    Science.gov (United States)

    Kirshner, R L; Green, R M

    1985-07-01

    We report a case of acute thrombosis of an abdominal aortic aneurysm secondary to a correctly applied and successful Heimlich maneuver. Although the Heimlich maneuver is generally safe and effective, this possible catastrophic consequence needs to be recognized.

  10. Proposal for Global Standard Maneuvering Orders for Tugboats

    Directory of Open Access Journals (Sweden)

    Ayumi Ishikura

    2013-12-01

    Full Text Available The use of “Standard Maneuvering Orders” for tugboats, vocabulary and phrases mutually pre-agreed between ships and tugboats, is essential for the former to provide clear direction for the latter when berthing or un-berthing safely. Tugboats will need time to change their posture before they take actions in response to orders from persons responsible for ships’ maneuvering. Therefore, when giving directions to change tugboats’ posture, persons who handle their ships are required to send out tug orders, with regard to “delay time,” a gap be-tween the orders from ships and the actions taken by tugboats. “Tug Orders” standardized and used in Japan are composed of the following three factors concerning towage work: tugboat’s motion, direction and engine power, but the author’s research shows that there are “Non-standard” special maneuvering orders other than those “standardized,” which causes such problems as a gap in perception between pilots and tugboat’s opera-tors, etc. The purpose of this paper is to research the delay time between orders for and actions by tugboats and consider the appropriate and safe timing of providing instructions to them, and then to propose globally-authorized “Standard Maneuvering Orders for tugboats”, discussing a problem involved in the use of the special orders used in Japan, and the way in which tug orders are used in other countries.

  11. Volunteer kinematics and reaction in lateral emergency maneuver tests

    NARCIS (Netherlands)

    Rooij, L. van; Elrofai, H.B.H.; Philippens, M.M.G.M.; Daanen, H.A.M.

    2013-01-01

    It is important to understand human kinematics and muscle activation patterns in emergency maneuvers for the design of safety systems and for the further development of human models. The objective of this study was to quantify kinematic behavior and muscle activation in simulated steering tests in s

  12. Acute abdominal aortic thrombosis following the Heimlich maneuver.

    Science.gov (United States)

    Ayerdi, Juan; Gupta, Sushil K; Sampson, Lawrence N; Deshmukh, Narayan

    2002-04-01

    Complications from the Heimlich maneuver are relatively infrequent. Two fatal cases of abdominal aortic thrombosis have been reported following this technique. We report on the first patient that suffered an acute thrombosis of the abdominal aorta and survived. Prompt recognition of this complication provides the only hope of survival from this rare and catastrophic complication.

  13. Heimlich's maneuver-assisted bronchoscopic removal of airway foreign body.

    Science.gov (United States)

    Solanki, Sohan Lal; Bansal, Shivendu; Khare, Arvind; Jain, Amit

    2011-01-01

    Aspiration of foreign bodies (FBs) by children can lead to serious illness and sometimes even death. Bronchoscopic removal of the FB is necessary to prevent from any catastrophic event. Sometimes bronchoscopic removal is not possible due to the larger size of the FB, sharp FB, or long duration FB. Tracheostomy is normally used for the removal of such FBs. The aim of this case report is to highlight the use of Heimlich maneuver for the removal of such FBs before opting invasive procedures. In the present case, a 5-year-old child was presented with history of FB aspiration 5 h back. After multiple failed bronchoscopic attempts to remove the FB it was decided to use Heimlich maneuver in the supine position. A single attempt of Heimlich maneuver expelled the FB into the oral cavity, which was removed by Magill's forceps. On repeated bronchoscope check, there was no remnant of FB. Child's further course of stay in hospital was uneventful. In conclusion, Heimlich maneuver may be useful in patient with failed bronchoscope removal of airway FBs before proceeding for tracheotomy or other invasive procedures.

  14. Ruptured aortic valve cusp: a complication of the Heimlich maneuver.

    Science.gov (United States)

    Chapman, J H; Menapace, F J; Howell, R R

    1983-07-01

    A case of traumatic rupture of the aortic valve as a complication of the Heimlich maneuver is presented. Conformation was made by comparative echocardiographic studies available from three months before and immediately following the incident. The patient refused surgical intervention and died one month later with severe congestive heart failure despite vigorous medical therapy.

  15. 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)

  16. Biologically inspired force enhancement for maritime propulsion and maneuvering

    CERN Document Server

    Weymouth, G D

    2016-01-01

    The move to high performance applications greatly increases the demand to produce large instantaneous fluid forces for high-speed maneuvering and improved power efficiency for sustained propulsion. Animals achieve remarkable feats of maneuvering and efficiency by changing their body shape to generate unsteady fluid forces. Inspired by this, we have studied a range of immersed bodies which drastically change their shape to produce fluid forces. These include relatively simple shape- changes, such as quickly changing the angle of attack of a foil to induce emergency stops and the use of tandem flapping foils to generate three times the average propulsive force of a single flapping foil. They also include more unconventional shape-changes such as high-speed retracting foil sections to power roll and dive maneuvers and the use of soft robotics to rapidly shrink the frontal area of an ellipsoid to power 68% efficient fast-start maneuvers or even completely cancel the drag force with 91% quasi-propulsive efficiency...

  17. Influence of breathing movements and Valsalva maneuver on vena caval dynamics

    Institute of Scientific and Technical Information of China (English)

    Alicia; Laborda; Sergio; Sierre; Mauro; Malvè; Ignacio; De; Blas; Ignatios; Ioakeim; William; T; Kuo; Miguel; Angel; De; Gregorio

    2014-01-01

    AIM: To study changes produced within the inferior vena cava(IVC) during respiratory movements and identify their possible clinical implications.METHODS: This study included 100 patients(46 women; 54 men) over 18 years of age who required an abdominal computed tomography(CT) and central venous access. IVC cross-sectional areas were measured on CT scans at three levels, suprarenal(SR), juxtarenal(JR) and infrarenal(IR), during neutral breathing and again during the Valsalva maneuver. All patientswere instructed on how to perform a correct Valsalva maneuver. In order to reduce the total radiation dose in our patients, low-dose CT protocols were used in all patients. The venous blood pressure(systolic, diastolic and mean) was invasively measured at the same three levels with neutral breathing and the Valsalva maneuver during venous port implantation. From CT scans, threedimensional models of the IVC were constructed and a collapsibility index was calculated for each patient. These data were then correlated with venous pressures and cross-sectional areas.RESULTS: The mean patient age was 51.64 ± 12.01 years. The areas of the ellipse in neutral breathing were 394.49 ± 85.83(SR), 380.10 ± 74.55(JR), and 342.72 ± 49.77 mm2(IR), and 87.46 ± 18.35(SR), 92.64 ± 15.36(JR) and 70.05 ± 9.64 mm2(IR) during the Valsalva(P s < 0.001). There was a correlation between areas in neutral breathing and in the Valsalva maneuver(P < 0.05 in all areas). Large areas decreased more than smaller areas. The collapsibility indices were 0.49 ± 0.06(SR), 0.50 ± 0.04(JR) and 0.50 ± 0.04(IR), with no significant differences in any region. Reconstructed three-dimensional models showed a flattening of the IVC during Valsalva, adopting an ellipsoid cross-sectional shape. The mean pressures with neutral breathing were 9.44 ± 1.78(SR), 9.40 ± 1.44(JR) and 8.84 ± 1.03 mmHg(IR), and 81.08 ± 21.82(SR), 79.88 ± 19.01(JR) and 74.04 ± 16.56 mmHg(IR) during Valsalva(P s < 0.001). There was a

  18. 47 CFR 80.1183 - Remote control for maneuvering or navigation.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 5 2010-10-01 2010-10-01 false Remote control for maneuvering or navigation... Communications § 80.1183 Remote control for maneuvering or navigation. (a) An on-board station may be used for remote control of maneuvering or navigation control systems aboard the same ship or, where that ship...

  19. Effects of different respiratory maneuvers on esophageal sphincters in obese patients before and during anesthesia.

    Science.gov (United States)

    de Leon, A; Thörn, S-E; Raoof, M; Ottosson, J; Wattwil, M

    2010-11-01

    Data on esophageal sphincters in obese individuals during anesthesia are sparse. The aim of the present study was to evaluate the effects of different respiratory maneuvers on the pressures in the esophagus and esophageal sphincters before and during anesthesia in obese patients. Seventeen patients, aged 28-68 years, with a BMI ≥ 35 kg/m², who were undergoing a laparoscopic gastric by-pass surgery, were studied, and pressures from the hypopharynx to the stomach were recorded using high-resolution solid-state manometry. Before anesthesia, recordings were performed during normal spontaneous breathing, Valsalva and forced inspiration. The effects of anesthesia induction with remifentanil and propofol were evaluated, and positive end-expiratory pressure (PEEP) 10 cmH₂O was applied during anesthesia. During spontaneous breathing, the lower esophageal sphincter (LES) pressure was significantly lower during end-expiration compared with end-inspiration (28.5 ± 7.7 vs. 35.4 ± 10.8 mmHg, PIGP) were unchanged. LES, BrP (PIGP (PIGP increased during Valsalva (PIGP. LES, BrP and IGP decreased during anesthesia but BrP remained positive in all patients. During the application of PEEP, esophageal pressures increased and this may have a protective effect against regurgitation. © 2010 The Authors. Journal compilation © 2010 The Acta Anaesthesiologica Scandinavica Foundation.

  20. Respiratory compliance but not gas exchange correlates with changes in lung aeration after a recruitment maneuver: an experimental study in pigs with saline lavage lung injury

    Science.gov (United States)

    Henzler, Dietrich; Pelosi, Paolo; Dembinski, Rolf; Ullmann, Annette; Mahnken, Andreas H; Rossaint, Rolf; Kuhlen, Ralf

    2005-01-01

    Introduction Atelectasis is a common finding in acute lung injury, leading to increased shunt and hypoxemia. Current treatment strategies aim to recruit alveoli for gas exchange. Improvement in oxygenation is commonly used to detect recruitment, although the assumption that gas exchange parameters adequately represent the mechanical process of alveolar opening has not been proven so far. The aim of this study was to investigate whether commonly used measures of lung mechanics better detect lung tissue collapse and changes in lung aeration after a recruitment maneuver as compared to measures of gas exchange Methods In eight anesthetized and mechanically ventilated pigs, acute lung injury was induced by saline lavage and a recruitment maneuver was performed by inflating the lungs three times with a pressure of 45 cmH2O for 40 s with a constant positive end-expiratory pressure of 10 cmH2O. The association of gas exchange and lung mechanics parameters with the amount and the changes in aerated and nonaerated lung volumes induced by this specific recruitment maneuver was investigated by multi slice CT scan analysis of the whole lung. Results Nonaerated lung correlated with shunt fraction (r = 0.68) and respiratory system compliance (r = 0.59). The arterial partial oxygen pressure (PaO2) and the respiratory system compliance correlated with poorly aerated lung volume (r = 0.57 and 0.72, respectively). The recruitment maneuver caused a decrease in nonaerated lung volume, an increase in normally and poorly aerated lung, but no change in the distribution of a tidal breath to differently aerated lung volumes. The fractional changes in PaO2, arterial partial carbon dioxide pressure (PaCO2) and venous admixture after the recruitment maneuver did not correlate with the changes in lung volumes. Alveolar recruitment correlated only with changes in the plateau pressure (r = 0.89), respiratory system compliance (r = 0.82) and parameters obtained from the pressure-volume curve

  1. A geostationary longitude acquisition planning algorithm. [for maneuver planning of geosynchronous satellites

    Science.gov (United States)

    Petruzzo, C. J.; Bryant, W. C., Jr.; Nickerson, K. G.

    1977-01-01

    The paper is concerned with the phase of the geosynchronous mission termed station acquisition, which involves the maneuvering of a spacecraft to its geostationary longitude by means of the spacecraft propulsion system. An algorithm which assists in maneuver planning is described, and examples of its use are presented. The algorithm can be applied when sequences of more than three maneuvers are to be expected. While, in general, three maneuvers are sufficient to achieve the desired end conditions when orbital mechanics are the only consideration, operational considerations may add constraints resulting in an increased number of maneuvers required.

  2. Maneuver Performance Assessment of the Cassini Spacecraft Through Execution-Error Modeling and Analysis

    Science.gov (United States)

    Wagner, Sean

    2014-01-01

    The Cassini spacecraft has executed nearly 300 maneuvers since 1997, providing ample data for execution-error model updates. With maneuvers through 2017, opportunities remain to improve on the models and remove biases identified in maneuver executions. This manuscript focuses on how execution-error models can be used to judge maneuver performance, while providing a means for detecting performance degradation. Additionally, this paper describes Cassini's execution-error model updates in August 2012. An assessment of Cassini's maneuver performance through OTM-368 on January 5, 2014 is also presented.

  3. Cassini Maneuver Experience for the Fourth Year of the Solstice Mission

    Science.gov (United States)

    Vaquero, Mar; Hahn, Yungsun; Stumpf, Paul; Valerino, Powtawche; Wagner, Sean; Wong, Mau

    2014-01-01

    After sixteen years of successful mission operations and invaluable scientific discoveries, the Cassini orbiter continues to tour Saturn on the most complex gravity-assist trajectory ever flown. To ensure that the end-of-mission target of September 2017 is achieved, propellant preservation is highly prioritized over maneuver cycle minimization. Thus, the maneuver decision process, which includes determining whether a maneuver is performed or canceled, designing a targeting strategy and selecting the engine for execution, is being continuously re-evaluated. This paper summarizes the maneuver experience throughout the fourth year of the Solstice Mission highlighting 27 maneuvers targeted to nine Titan flybys.

  4. Maneuver Performance Assessment of the Cassini Spacecraft Through Execution-Error Modeling and Analysis

    Science.gov (United States)

    Wagner, Sean

    2014-01-01

    The Cassini spacecraft has executed nearly 300 maneuvers since 1997, providing ample data for execution-error model updates. With maneuvers through 2017, opportunities remain to improve on the models and remove biases identified in maneuver executions. This manuscript focuses on how execution-error models can be used to judge maneuver performance, while providing a means for detecting performance degradation. Additionally, this paper describes Cassini's execution-error model updates in August 2012. An assessment of Cassini's maneuver performance through OTM-368 on January 5, 2014 is also presented.

  5. Development of a flight test maneuver autopilot for an F-15 aircraft

    Science.gov (United States)

    Alag, G. S.; Duke, E. L.

    1985-01-01

    An autopilot can be used to provide precise control to meet the demanding requirements of flight research maneuvers with high-performance aircraft. This paper presents the development of control laws for a flight test maneuver autopilot for an F-15 aircraft. A linear quadratic regulator approach is used to develop the control laws within the context of flight test maneuver requirements by treating the maneuver as a finite time tracking problem with regulation of state rates. Results are presented to show the effectiveness of the controller in insuring acceptable aircraft performance during a maneuver.

  6. Clinical Presentation and Conservative Management of Tympanic Membrane Perforation during Intrapartum Valsalva Maneuver

    Directory of Open Access Journals (Sweden)

    Jonathan D. Baum

    2010-01-01

    Full Text Available Background. Tympanic membrane perforation may occur when ear pressures are excessive, including valsalva maneuver associated with active labor and vaginal delivery. A pressure differential across the eardrum of about 5 psi can cause rupture; the increased intraabdominal pressure spikes repeatedly manifested by “pushing” during second-stage labor easily approach (and may exceed this level. Material and Method. We describe a healthy 21-year old nulliparous patient admitted in active labor at 39-weeks' gestational age. Results. Blood appeared asymptomatically in the left ear canal at delivery during active, closed-glottis pushing. Otoscopic examination confirmed perforation of the left tympanic membrane. Complete resolution of the eardrum rupture was noted at postpartum check-up six weeks later. Conclusion. While the precise incidence of intrapartum tympanic membrane rupture is not known, it may be unrecognized without gross blood in the ear canal or subjective hearing loss following delivery. Only one prior published report on tympanic membrane perforation during delivery currently appears in the medical literature; this is the first English language description of the event. Since a vigorous and repetitive valsalva effort is common in normal vaginal delivery, clinicians should be aware of the potential for otic complications associated with the increased intraabdominal pressure characteristic of this technique.

  7. The effects of different oxygen concentrations on recruitment maneuver during general anesthesia for laparoscopic surgery.

    Science.gov (United States)

    Topuz, Ufuk; Salihoglu, Ziya; Gokay, Banu V; Umutoglu, Tarik; Bakan, Mefkur; Idin, Kadir

    2014-10-01

    Recruitment maneuvers (RMs), which aim to ventilate the collaborated alveolus by temporarily increasing the transpulmonary pressure, have positive effects in relation to respiration, mainly oxygenation. Although many studies have defined the pressure values used during RM and the application period, our knowledge of the effects of different oxygen concentrations is limited. In this study, we aimed to determine the effects of different oxygen concentrations during RM on the arterial oxygenation and respiration mechanics in laparoscopic cases. Thirty-two patients undergoing laparoscopic cholecystectomy were recruited into the study. The patients were randomly divided into 2 groups. RM with a 30% oxygen concentration was performed in patients within the first group (group I, n=16), whereas patients in the second group (group II, n=16) received RM with 100% oxygen. To study respiratory mechanics, dynamic compliance (Cdyn), airway resistance (Raw), and peak inspiratory pressure were measured at 3 different times: 5 minutes after anesthesia induction, 5 minutes after the abdomen was insufflated, and 5 minutes after the abdomen was desufflated. Arterial blood gases were measured during surgery and 30 minutes after surgery (postoperative). The average postoperative partial arterial oxygen pressure values of the patients in groups I and II were 121 and 98 mm Hg, respectively. The difference between the groups was statistically significant. In addition, the decrease in compliance from induction values after desufflation in group II was statistically significant. On the basis of our results, maintaining oxygen concentrations below 100% during RM may be more beneficial in terms of respiratory mechanics and gas exchange.

  8. Compressed Sensing ISAR Reconstruction Considering Highly Maneuvering Motion

    Directory of Open Access Journals (Sweden)

    Ahmed Shaharyar Khwaja

    2017-03-01

    Full Text Available In this report, we propose compressed sensing inverse synthetic aperture radar (ISAR imaging in the presence of highly maneuvering motion using a modified orthogonal matching pursuit (OMP reconstruction algorithm. Unlike existing methods where motion is limited to first- or second-order phase terms, we take into account realistic motion of a maneuvering target that can involve a third-order phase term corresponding to the rate of rotational acceleration. In addition, unlike existing fixed dictionary-based methods, which require designing a large dictionary that needs to take into account all of the possible motion parameters, we propose a modified OMP reconstruction method that requires a dictionary only based on the first-order phase term and estimates the secondand third-order phase terms using an optimization algorithm. Simulation examples and comparison with existing methods show the viability of our approach for imaging moving targets consisting of higher order motion.

  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. A synthetic environment for visualization and planning of orbital maneuvers

    Science.gov (United States)

    Ellis, Stephen R.; Grunwald, Arthur J.

    An interactive proximity operations planning system, which allows on-site planning of fuel-efficient, multi-burn maneuvers in a potential multi-space-craft environment has been developed and tested. This display system most directly assists planning by providing visual feedback in a synthetic virtual space that aids visualization of trajectories and their constraints. Its most significant features include (1) an 'inverse dynamics' algorithm that removes control nonlinearities facing the operator and (2) a stack-oriented action-editor that reduces the order of control and creates, through a 'geometric spreadsheet,' the illusion of an inertially stable environment. This synthetic environment provides the user with control of relevant static and dynamic properties of way-points during small orbital changes allowing independent solutions to otherwise coupled problems of orbital maneuvering.

  11. Single step optimization of manipulator maneuvers with variable structure control

    Science.gov (United States)

    Chen, N.; Dwyer, T. A. W., III

    1987-01-01

    One step ahead optimization has been recently proposed for spacecraft attitude maneuvers as well as for robot manipulator maneuvers. Such a technique yields a discrete time control algorithm implementable as a sequence of state-dependent, quadratic programming problems for acceleration optimization. Its sensitivity to model accuracy, for the required inversion of the system dynamics, is shown in this paper to be alleviated by a fast variable structure control correction, acting between the sampling intervals of the slow one step ahead discrete time acceleration command generation algorithm. The slow and fast looping concept chosen follows that recently proposed for optimal aiming strategies with variable structure control. Accelerations required by the VSC correction are reserved during the slow one step ahead command generation so that the ability to overshoot the sliding surface is guaranteed.

  12. Broken-Plane Maneuver Applications for Earth to Mars Trajectories

    Science.gov (United States)

    Abilleira, Fernando

    2007-01-01

    Optimization techniques are critical when investigating Earth to Mars trajectories since they have the potential of reducing the total (delta)V of a mission. A deep space maneuver (DSM) executed during the cruise may improve a trajectory by reducing the total mission V. Nonetheless, DSMs not only may improve trajectory performance (from an energetic point of view) but also open up new families of trajectories that would satisfy very specific mission requirements not achievable with ballistic trajectories. In the following pages, various specific examples showing the potential advantages of the usage of broken plane maneuvers will be introduced. These examples correspond to possible scenarios for Earth to Mars trajectories during the next decade (2010-2020).

  13. Does dragonfly's abdomen flexion help with fast turning maneuvers?

    Science.gov (United States)

    Liu, Geng; Li, Chengyu; Dong, Haibo; Flow Simulation Research Group Team

    2013-11-01

    Dragonflies are able to achieve fast turning maneuvers during take-off flights. Both asymmetric wing flapping and abdomen flexion have been observed during the fast turning. It's widely thought that the asymmetric wing beats are responsible of producing the aerodynamic moment needed for the body rotation. However, the dynamic effect of the abdomen flexion is not clear yet. In this study, an integrated experimental and computational approach is used to study the underlying dynamic effect of dragonfly abdomen flexion. It's found that dragonfly abdomen tended to bend towards the same side as the body reorienting to. Quantitative analysis have shown that during take-off turning maneuver the abdomen flexion can modulate the arm of force by changing the position of the center of mass relative to the thorax. As a result, roll and yaw moments produced by the wing flapping can be enhanced. This work is supported by NSF CBET-1313217. This work is supported by NSF CBET-1313217.

  14. On steering a sailing ship in a wearing maneuver

    DEFF Research Database (Denmark)

    Jouffroy, Jerome

    Compared to more conventional ships, little attention was given to nonlinear control design for ships sailing by the wind. Following our previous work, this paper addresses the issue of trajectory and reference input generation for a model that imitates the general behavior of sailing vessels. Sp....... Specifically, we consider the generation of paths to perform a wearing maneuver. A feedforward controller scheme is then introduced to steer the modeled vehicle along this maneuver, and simulation results are presented as an illustration.......Compared to more conventional ships, little attention was given to nonlinear control design for ships sailing by the wind. Following our previous work, this paper addresses the issue of trajectory and reference input generation for a model that imitates the general behavior of sailing vessels...

  15. 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.

  16. Acute bag-valve breathing maneuvers plus manual chest compression is safe during stable septic shock: a randomized clinical trial.

    Science.gov (United States)

    Blattner, Clarissa Netto; Santos, Rafael Saldanha Dos; Dias, Fernando Suparregui; Dias, Alexandre Simões; Mestriner, Régis Gemerasca; Vieira, Silvia Regina Rios

    2017-01-01

    To evaluate the effects of bag-valve breathing maneuvers combined with standard manual chest compression techniques on safety, hemodynamics and oxygenation in stable septic shock patients. A parallel, assessor-blinded, randomized trial of two groups. A computer-generated list of random numbers was prepared by an independent researcher to allocate treatments. The Intensive Care Unit at Hospital São Lucas, Pontifícia Universidade Católica do Rio Grande do Sul. Fifty-two subjects were assessed for eligibility, and 32 were included. All included subjects (n = 32) received the allocated intervention (n = 19 for the Experimental Group and n = 13 for the Control Group). Twenty minutes of bag-valve breathing maneuvers combined with manual chest compression techniques (Experimental Group) or chest compression, as routinely used at our intensive care unit (Control Group). Follow-up was performed immediately after and at 30 minutes after the intervention. Mean artery pressure. All included subjects completed the trial (N = 32). We found no relevant effects on mean artery pressure (p = 0.17), heart rate (p = 0.50) or mean pulmonary artery pressure (p = 0.89) after adjusting for subject age and weight. Both groups were identical regarding oxygen consumption after the data adjustment (p = 0.84). Peripheral oxygen saturation tended to increase over time in both groups (p = 0.05), and there was no significant association between cardiac output and venous oxygen saturation (p = 0.813). No clinical deterioration was observed. A single session of bag-valve breathing maneuvers combined with manual chest compression is hemodynamically safe for stable septic-shocked subjects over the short-term.

  17. CFD investigations of the aerodynamics of vehicle overtaking maneuvers

    Science.gov (United States)

    Uddin, Mesbah; Chellaram, Arune Dhiren; Robinson, Austin Clay

    2017-06-01

    When two vehicle bodies are involved in a passing maneuver, interesting and intricate aerodynamic interactions occur between them. Such passing maneuvers are very important in racing and have been an area of active interest in motorsports for quite some time. The existing literature shows only a few studies in this area, and, as such, very little is known about the complex aerodynamics of racing in proximity. This paper presents a Computational Fluid Dynamics (CFD) methodology capable of describing the transient effects that occur in this scenario. This is achieved by simulating two tandem simplified vehicle bodies, the Ahmed body, which were placed in a virtual wind tunnel. One Ahmed body was kept stationary, while the other was allowed to move in the longitudinal direction with a relatively low velocity. In order to achieve reliable CFD results when one of the solid objects is moving, a new meshing methodology, called the overset mesh model, was implemented in the CFD process. The simulations were run using Star CCM+, a commercial finite-volume CFD program, in which the unsteady Reynolds Averaged Navier-Stokes (URANS) solver was applied. The CFD results are compared against fully transient and quasi-steady-state experimental results where encouraging correlations between the CFD and experiments are observed. The veracity of the CFD work presented in this paper provides significant insight into the complex aerodynamics of a passing maneuver, and lays the foundation for further analysis in this area using more complex vehicle shapes and more complex tandem racing or passing maneuvers at a yaw angle.

  18. Beyond Mission Command: Maneuver Warfare for Cyber Command and Control

    Science.gov (United States)

    2015-05-18

    elements with maneuver warfare, mission command’s decentralization of execution through the use of mission-type orders is a more centralized form... decentralized command and control organization will instill an innovative organizational culture. Innovation will be able to freely prosper in an...warfare’s decentralized command and control doctrine to maximize military cyberspace operations. Since the establishment of U.S. Cyber Command in 2009

  19. Measuring Pilot Proficiency on an Instrument Training Maneuver

    Science.gov (United States)

    1977-08-01

    featmr• of the Advanced Simulator for Pilot Training ( ASPT ) could be suc- cess tuj ly used to facilitate the development and validation of a recording...for the instrument training maneuver Vertical S-A in which the unique record/playback features of the Advanced Simulator for Pilot Training ( ASPT ) were...the ASPT revealed several format and observe--workload problems that needed correction. SFollowing revision, the booklet (Appendix A) was given a

  20. Firepower, Maneuver, and the Operational Level of War

    Science.gov (United States)

    1992-05-15

    wasn’t." Field Marshal Bernard Law Montgomery and General George S. Patton, two of the premier Allied field commanders in the European Theater of...higher headquarters and grafted onto another. Moreover, such changes are detrimental in a moral sense to the espirit and comradeship that most soldiers...Operation Barbarossa s-emed to exemplify "distrtbuted free maneuver" with three non-supporting thrusts into the Soviet Union , and with freGuent

  1. 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

  2. Computing and Visualizing Reachable Volumes for Maneuvering Satellites

    Science.gov (United States)

    2011-09-01

    Computing and Visualizing Reachable Volumes for Maneuvering Satellites Ming Jiang, Willem H. de Vries, Alexander J. Pertica , Scot S. Olivier...Handbook. Elsevier, 2004. 6. M. Jiang, M. Andereck, A. J. Pertica , and S. S. Olivier. A Scalable Visualization System for Improving Space Situational...Jiang, J. Leek, J. L. Levatin, S. Nikolaev, A. J. Pertica , D. W. Phillion, H. K. Springer, and W. H. de Vries. High-Performance Computer Modeling of

  3. Variable structure attitude maneuver and vibration control of flexible spacecraft

    Institute of Scientific and Technical Information of China (English)

    HU Qing-lei; MA Cuang-fu

    2008-01-01

    A dual-stage control system design method is presented for the three-axis-rotational maneuver and vibration stabilization of a spacecraft with flexible appendages embedded with piezoceramics as sensor and actuator.In this design approach,the attitude control and the vibration suppression sub-systems ale designed separately using the lower order model.The design of attitude controller is based on the variable structure control (VSC)theory leading to a discontinuous control law.This controller accomplishes asymptotic attitude maneuvering in the closed-loop system and is insensitive to the interaction of elastic modes and uncertainty in the system.To actively suppress the flexible vibrations,the modal velocity feedback control method is presented by using piezoelectric materials as additional sensor and actuator bonded on the surface of the flexible appendages.In addition,a special configuration of actuators for three-axis attitude control is also investigated:the pitch attitude controlled by a momentum wheel,and the roll/yaw control achieved by on-off thrustem.which is modulated by pulse width pulse frequency modulation technique to construct the proper control torque history.Numerical simulations performed show that the rotational maneuver and vibration suppression ale accomplished in spite of the presence of disturbance torque and parameter uncertainty.

  4. Actuator characterization of a man-portable precision maneuver concept

    Directory of Open Access Journals (Sweden)

    Ilmars Celmins

    2014-06-01

    Full Text Available The US Army Research Laboratory is conducting research to explore technologies that may be suitable for maneuvering man-portable munitions. Current research is focused on the use of rotary actuators with spin-stabilized munitions. A rotary actuator holds the potential of providing a low-power solution for guidance of a spinning projectile. This is in contrast to a linear (reciprocating actuator which would need to constantly change direction, resulting in large accelerations which in turn would require large forces, thereby driving up the actuator power. A rotational actuator would be operating at a fairly constant rotation rate once it is up to speed, resulting in much lower power requirements. Actuator experiments conducted over a variety of conditions validate the dynamic models of the actuator and supply the data necessary for model parameter estimation. Actuator performance metrics of spin rate response, friction, and power requirements were derived from the data. This study indicates that this class of maneuver concepts can be driven with these actuators. These results enable actuator design and multi-disciplinary simulation of refined maneuver concepts for a specific application.

  5. Vehicle Optimal Velocity Curves for Minimum-Time Maneuver

    Directory of Open Access Journals (Sweden)

    Li-xia Zhang

    2014-02-01

    Full Text Available A problem in vehicle minimum-time maneuver is the assumption that a vehicle passes through a given path in a minimal amount of time without deviating from the boundary of the given path. Vehicle handling inverse dynamics provides a new perspective to solve such problem. Based on inverse dynamics, this paper transformed the problem of optimal vehicle velocity for minimum-time maneuver into that of optimal control with the objective function of minimum time. The path for minimum vehicle travel time and the optimal control model were established. The optimal velocity curves for three types of paths, namely, monotonically increasing path, monotonically decreasing path, and constant radius path, were analyzed. On this basis, the optimal velocity curves were solved for two kinds of concrete paths: a path of decreasing curvature radius followed by a path of increasing curvature radius and another path of increasing curvature radius followed by a path of decreasing curvature radius. Nine cases of possible optimal velocity curves were acquired. The optimal velocity curve of the given path, that is, a parabola followed by a semicircle, was obtained. Optimal velocity curves can be used as reference for vehicle minimum-time maneuver, which is an important issue for driver safety in fast-moving vehicles.

  6. An Autonomous Onboard Targeting Algorithm Using Finite Thrust Maneuvers

    Science.gov (United States)

    Scarritt, Sara K.; Marchand, Belinda G.; Brown, Aaron J.; Tracy, William H.; Weeks, Michael W.

    2010-01-01

    In earlier investigations, the adaptation and implementation of a modified two-level corrections (or targeting) process as the onboard targeting algorithm for the Trans-Earth Injection phase of Orion is presented. The objective of that targeting algorithm is to generate the times of ignition and magnitudes of the required maneuvers such that the desired state at entry interface is achieved. In an actual onboard flight software implementation, these times of ignition and maneuvers are relayed onto Flight Control for command and execution. Although this process works well when the burn durations or burn arcs are small, this might not be the case during a contingency situation when lower thrust engines are employed to perform the maneuvers. Therefore, a new model for the two-level corrections process is formulated here to accommodate finite burn arcs. This paper presents the development and formulation of the finite burn two-level corrector, used as an onboard targeting algorithm for the Trans-Earth Injection phase of Orion. A performance comparison between the impulsive and finite burn models is also presented. The present formulation ensures all entry constraints are met, without violating the available fuel budget, while allowing for low-thrust scenarios with long burn durations.

  7. Development of NVG test maneuvers for civilian aircraft

    Science.gov (United States)

    Jennings, Sion; Craig, Greg; Carignan, Stephan; Fischer, Heiko; Brulotte, Michel

    2008-04-01

    This document provides an overview of helicopter flight-test methods used to evaluate night vision goggles at the National Research Council of Canada's Institute for Aerospace Research. These techniques have been used to examine the performance of display systems in actual field conditions. The flight evaluations were based, in large part, on standard flight test maneuvers and rating systems outlined in Aeronautical Design Standard ADS-33. The document describes NVG test maneuvers developed from ADS-33 principles, including a high hover, a mirror C, a vertical descent, a parallel lateral translation, a turn about the tail, a confined area staged landing, a brown-out/white-out simulation and a lit pirouette. The overview also comprises a description of methods for controlling the cueing environment. These methods include an appropriate selection of maneuvers as well as devices for limiting pilot vision such as goggles with filters and apertures, and other devices. The paper concludes with a short discussion on the merits of developing accurate in-flight tests capable of resolving performance differences among displays.

  8. Missile-Borne SAR Raw Signal Simulation for Maneuvering Target

    Directory of Open Access Journals (Sweden)

    Weijie Xia

    2016-01-01

    Full Text Available SAR raw signal simulation under the case of maneuver and high-speed has been a challenging and urgent work recently. In this paper, a new method based on one-dimensional fast Fourier transform (1DFFT algorithm is presented for raw signal simulation of maneuvering target for missile-borne SAR. Firstly, SAR time-domain raw signal model is given and an effective Range Frequency Azimuth Time (RFAT algorithm based on 1DFFT is derived. In this algorithm, the “Stop and Go” (SaG model is adopted and the wide radar scattering characteristic of target is taken into account. Furthermore, the “Inner Pulse Motion” (IPM model is employed to deal with high-speed case. This new RFAT method can handle the maneuvering cases, high-speed cases, and bistatic radar cases, which are all possible in the missile-borne SAR. Besides, this raw signal simulation adopts the electromagnetic scattering calculation so that we do not need a scattering rate distribution map as the simulation input. Thus, the multiple electromagnetic reflections can be considered. Simulation examples prove the effectiveness of our method.

  9. 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.

  10. An Autonomous Onboard Targeting Algorithm Using Finite Thrust Maneuvers

    Science.gov (United States)

    Scarritt, Sara K.; Marchand, Belinda G.; Weeks, Michael W.

    2009-01-01

    In earlier investigations, the adaptation and implementation of a modified two-level corrections process as the onboard targeting algorithm for the Trans-Earth Injection phase of Orion is presented. The objective of that targeting algorithm is to generate the times of ignition and magnitudes of the required maneuvers such that the desired state at entry interface is achieved. In an actual onboard flight software implementation, these times of ignition and maneuvers are relayed onto Flight Control for command and execution. Although this process works well when the burn durations or burn arcs are small, this might not be the case during a contingency situation when lower thrust engines are employed to perform the maneuvers. Therefore, a new version of the modified two-level corrections process is formulated to handle the case of finite burn arcs. This paper presents the development and formulation of that finite burn modified two-level corrections process which can again be used as an onboard targeting algorithm for the Trans-Earth Injection phase of Orion. Additionally, performance results and a comparison between the two methods are presented. The finite burn two-level corrector formulation presented here ensures the entry constraints at entry interface are still met without violating the available fuel budget, while still accounting for much longer burn times in its design.

  11. ALGORITHMS FOR TRACKING MANEUVERING TARGET WITH PHASED ARRAY RADAR

    Institute of Scientific and Technical Information of China (English)

    1998-01-01

    Several typical algorithms for tracking maneuvering target with phased array radar are studied in this paper. The constant gain filter with multiple models is analyzed. A typical method for adaptively controlling the sampling interval is modified. The performance of the single model and multiple model estimator with uniform and variable sampling interval are evaluated and compared. It is shown by the simulation results that it is necessary to apply the adaptive sampling policy based on the multiple model method when the maneuvering targets are tracked by the phased array radar since saving radar resources is more important. The adaptive algorithms of variable sampling interval are better than the algorithms of variable model. The adaptive policy to determine the sampling interval based on multiple model are superior than those based on the single-model filter, because IMM estimator can adapt to the maneuver more quickly and the prediction covariance of IMM is the more sensitive and more reliable index than residual to determine the sampling interval. With IMM-based method, lower sampling interval is required for a certain accuracy.

  12. Actuator characterization of a man-portable precision maneuver concept

    Institute of Scientific and Technical Information of China (English)

    Ilmars CELMINS; Frank E.FRESCONI; Bryant P.NELSON

    2014-01-01

    The US Army Research Laboratory is conducting research to explore technologies that may be suitable for maneuvering man-portable munitions. Current research is focused on the use of rotary actuators with spin-stabilized munitions. A rotary actuator holds the potential of providing a low-power solution for guidance of a spinning projectile. This is in contrast to a linear (reciprocating) actuator which would need to constantly change direction, resulting in large accelerations which in turn would require large forces, thereby driving up the actuator power. A rotational actuator would be operating at a fairly constant rotation rate once it is up to speed, resulting in much lower power requirements. Actuator experiments conducted over a variety of conditions validate the dynamic models of the actuator and supply the data necessary for model parameter estimation. Actuator performance metrics of spin rate response, friction, and power requirements were derived from the data. This study indicates that this class of maneuver concepts can be driven with these actuators. These results enable actuator design and multi-disciplinary simulation of refined maneuver concepts for a specific application.

  13. "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.

  14. 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.

  15. Self pressuring HTP feed systems

    Energy Technology Data Exchange (ETDEWEB)

    Whitehead, J.

    1999-10-14

    Hydrogen peroxide tanks can be pressurized with decomposed HTP (high test hydrogen peroxide) originating in the tank itself. In rocketry, this offers the advantage of eliminating bulky and heavy inert gas storage. Several prototype self-pressurizing HTP systems have recently been designed and tested. Both a differential piston tank and a small gas-driven pump have been tried to obtain the pressure boost needed for flow through a gas generator and back to the tank. Results include terrestrial maneuvering tests of a prototype microsatellite, including warm gas attitude control jets.

  16. A Recruiting Maneuver Algorithm in Patients with Early Acute Respiratory Distress Syndrome

    Directory of Open Access Journals (Sweden)

    D. I. Levikov

    2011-01-01

    Full Text Available Objective: to evaluate the efficiency of a recruiting maneuver (RM and adjustment of positive end-expiratory pressure (PEEP in patients with early acute respiratory distress syndrome (ARDS. Subjects and methods. The study enrolled 16 patients (14 men and 2 women aged 46 to 78 years (range 62±5.6 years with ARDS of various genesis. RM was made, by stepwisely increasing PEEP and inspiratory pressure under the control of dynamic lung compliance and hemodynamic parameters. The values of blood gas composition and hemodynamics were determined during the study. Results. RM caused an increase in oxygenation index (OI from 153.5±48.3 to 348.5±53.2 mm Hg. Oxygenation values returned to the baseline levels 30—40 min after the PEEP was set at the closure point of +2 cm H2O. If the set PEEP was 8—10 cm H2O higher than the objective, the effect of RM was retained for as long as 24 hours. When RM was performed using the maximum pressure of 50—60 cm H2O, the cardiac index (CI was lower in all the patients and 30—50% of the baseline values were achieved in all cases, which required the optimization of cardiotonic therapy. The time of this pronounced reduction in cardiac output with RM was not longer than 5 min. After RM, during mechanical ventilation with 18—26 cm H2O PEEP, the CI did not practically differ from the baseline values (3.31±0.41 and 3.37±0.36 l/min/m2, respectively, though the dopamine dose required to maintain normal hemodynamics was somewhat higher (7.5±2.3 and 6.3±2.6 ^g/kg/min. Conclusion. Analysis of the given cases suggests that RM is highly effective in patients at the early stages of acute lung injury. The duration of RM effects may depend on the set PEEP level in individual cases. Setting PEEP at a level of +2—4 cm H2O fails to prevent repeated alveolar derecruitment in a number of patients. In these cases, it is expedient to individually adjust PEEP levels, by taking into account the long-term changes in OI and Cdyn. In

  17. The clinical observation of endoscopic variceal ligation and tissue glue injection therapy in the treatment of patients with esophageal and gastric fundal varices%内镜下套扎和组织胶注射分别治疗食管和胃底静脉曲张患者的临床观察

    Institute of Scientific and Technical Information of China (English)

    王红建; 陈永忠; 冯百岁; 魏岩岩; 李建生

    2011-01-01

    Objective To explore the therapeutic effects and value of endoscopic variceal ligation and tissue glue injection therapy in esophageal and gastric fundal varices.Methods 184 patients with severe esophageal varices underwent endoscopic variceal ligation treatment,and 32 cases of those accompanied with gastric fundal varices were treated with tissue glue injection therapy.All patients were followed-up for 6-months to observe the therapeutic effects and complication of endoscopic variceal ligation and tissue glue injection therapy.Results The effective rate of endoscopic variceal ligation in severe esophageal varices was 71.74 % ( 132/184 ),the rate of acute hemostasis was 95.00%(57/60)and the rate of complication was 2.17 % (4/184).The effective rate of tissue glue injection in gastric fundal varices was 100% (32/32) and the rate of complication was 21.88% (7/32) (7 cases with refractory ulcers in injection site,2 of refractory ulcers cases with bleeding).There was no perforation and severe infection complications.Conclusion Endoscopic variceal ligation and tissue glue injection therapy have good therapeutic effects in esophageal and gastric fundal varices.%目的 探讨内镜下套扎和组织胶注射治疗食管胃底静脉曲张的疗效和价值.方法 予184例重度食管静脉曲张患者内镜下套扎治疗,其中32例伴胃底静脉曲张者还进行内镜下组织胶注射治疗.随访6个月并观察内镜下套扎和组织胶注射治疗的疗效和并发症.结果 内镜下套扎治疗重度食管静脉曲张的有效率为71.74%(132/184),急诊止血率为95.00%(57/60),并发症(食管套扎部位瘢痕狭窄需行扩张治疗)发生率为2.17%(4/184).内镜下组织胶注射治疗胃底静脉曲张的有效率为100%(32/32),并发症(注射部位难治性溃疡7例,其中难治性溃疡并出血2例)发生率为21.88%(7/32).均无穿孔、重度感染并发症发生.结论 内镜下套扎和组织胶注射治疗食管和胃底静脉曲张疗效良好.

  18. Investigation into the flow field around a maneuvering submarine using a Reynolds-averaged Navier-Stokes code

    Science.gov (United States)

    Rhee, Bong

    The accurate and efficient prediction of hydrodynamic forces and moments on a maneuvering submarine has been achieved by investigating the flow physics involving the interaction of the vortical flow shed from the sail and the cross-flow boundary layer of the hull. In this investigation, a Reynolds-Averaged Navier-Stokes (RANS) computer code is used to simulate the most important physical effects related to maneuvering. It is applied to a generic axisymmetric body with the relatively simple case of the flow around an unappended hull at an angle of attack. After the code is validated for this simple case, it is validated for the case of a submarine with various appendages attached to the hull moving at an angle of drift. All six components of predicted forces and moments for various drift angles are compared with experimental data. Calculated pressure coefficients along the azimuthal angle are compared with experimental data and discussed to show the effect of the sail and the stern appendages. To understand the main flow features for a submarine in a straight flight, the RANS code is applied to simulate SUBOFF axisymmetric body at zero angle of attack in a straight-line basin. Pressure coefficient, skin friction coefficient, mean velocity components and the Reynolds shear stresses are compared with experimental data and discussed. The physical aspects of the interaction between the vortical flow shed by the sail and the cross-flow boundary layer on the hull are explained in greater detail. The understanding of this interaction is very important to characterize accurately the hydrodynamic behavior of a maneuvering submarine.

  19. Effectiveness of Chin-tuck Maneuver to Facilitate Swallowing in Neurologic Dysphagia.

    Science.gov (United States)

    Saconato, Mariana; Chiari, Brasilia Maria; Lederman, Henrique Manoel; Gonçalves, Maria Inês Rebelo

    2016-01-01

    Introduction The chin-tuck maneuver is the most frequently employed postural maneuver in the treatment of neurogenic oropharyngeal dysphagia caused by encephalic vascular strokes and degenerative diseases. Objective The purpose of this study was to investigate the effectiveness of this maneuver in patients with neurogenic dysphagia and factors that could interfere in it. Methods In this retrospective cohort, we analyzed the medical files and videofluoroscopy exams of 35 patients (19 male - 54% and 16 female - 46%; age range between 20 and 89 years old; mean = 69 years). Results The results suggest that the effectiveness of chin-tuck maneuver is related to the overall degree of dysphagia: the more severe the dysphagia, the less effective the maneuver. Conclusion Chin-tuck maneuver should benefit dysphagic patients with delay in the swallowing trigger, reduced laryngeal elevation, and difficulties to swallow liquids, but is not the best compensatory strategy for patients with severe dysphagia.

  20. Cassini Orbit Trim Maneuvers at Saturn - Overview of Attitude Control Flight Operations

    Science.gov (United States)

    Burk, Thomas A.

    2011-01-01

    The Cassini spacecraft has been in orbit around Saturn since July 1, 2004. To remain on the planned trajectory which maximizes science data return, Cassini must perform orbit trim maneuvers using either its main engine or its reaction control system thrusters. Over 200 maneuvers have been executed on the spacecraft since arrival at Saturn. To improve performance and maintain spacecraft health, changes have been made in maneuver design command placement, in accelerometer scale factor, and in the pre-aim vector used to align the engine gimbal actuator prior to main engine burn ignition. These and other changes have improved maneuver performance execution errors significantly since 2004. A strategy has been developed to decide whether a main engine maneuver should be performed, or whether the maneuver can be executed using the reaction control system.

  1. Quantas medidas de pressões respiratórias são necessárias para se obterem medidas máximas em pacientes com tetraplegia? ¿Cuántas maniobras son necesarias para llegar a las presiones máximas en pacientes con tetraplejía? How many maneuvers of respiratory pressures are required to obtain maximal values in patients with quadriplegia?

    Directory of Open Access Journals (Sweden)

    Ada Clarice Gastaldi

    2010-06-01

    Full Text Available INTRODUÇÃO: pressões inspiratórias (PImax ou expiratórias (PEmax máximas constituem um método simples e não-invasivo para avaliação da força de músculos respiratórios e auxiliam na identificação de fraqueza dos músculos respiratórios, presente em diversas doenças e situações clínicas, como a tetraplegia. OBJETIVO: avaliar o número de manobras necessárias para atingir as pressões máximas em pacientes com tetraplegia. MÉTODOS: oito pacientes com tetraplegia (sete homens, média de idade de 37,8±11,96 anos, com diagnóstico de lesão raquimedular cervical completa realizaram 10 medidas de PImax e PEmax nas posições sentada e deitada, totalizando 320 medidas. Os dados foram comparados pelo teste de Wilcoxon (pINTRODUCCIÓN: las presiones inspiratorias (PImax y espiratorias (PEmax máximas constituyen un método simple y no invasivo para evaluar la fuerza de los músculos respiratorios, y ayudan a identificar la debilidad de los músculos respiratorios presente en diferentes enfermedades y situaciones clínicas, como la tetraplejía. OBJETIVO: evaluar el número de maniobras necesarias para llegar a las presiones máximas en pacientes con tetraplejía. MÉTODOS: fueron incluidos ocho pacientes con tetraplejía (siete hombres, con edad media de 37,8±11,96 años y diagnóstico de lesión cervical raquis medular completa, a lo que se le realizaron 10 mediciones de PImax y PEmax en posición sentado y acostado, totalizando 320 mediciones. Los datos fueron comparados por el test de Wilcoxon (pINTRODUCTION: maximum inspiratory (IPmax and expiratory (EPmax pressures constitute a simple noninvasive method for evaluation of respiratory muscle strength which helps in the identification of muscle weakness usually present in several diseases and clinical situations, such as quadriplegia. OBJECTIVE: to assess the number of maneuvers needed to achieve maximum pressures in patients with quadriplegia. METHODS: eight quadriplegic

  2. Quantas medidas de pressões respiratórias são necessárias para se obterem medidas máximas em pacientes com tetraplegia? ¿Cuántas medidas de presiones respiratorias son necesarias para obtener mediciones máximas en pacientes con tetraplejia? How many maneuvers of respiratory pressures are required to obtain maximal values in patients with quadriplegia?

    Directory of Open Access Journals (Sweden)

    Ada Clarice Gastaldi

    2009-12-01

    Full Text Available INTRODUÇÃO: pressões inspiratórias (PImax ou expiratórias (PEmax máximas constituem um método simples e não-invasivo para avaliação da força de músculos respiratórios e auxiliam a identificação de fraqueza dos músculos respiratórios, presente em diversas doenças e situações clínicas, como a tetraplegia. OBJETIVO: avaliar o número de manobras necessárias para atingir as pressões máximas em pacientes com tetraplegia. MÉTODOS: oito pacientes com tetraplegia (sete homens, média de idade de 37,8±11,96 anos, com diagnóstico de lesão raquimedular cervical completa realizaram 10 medidas de PImax e PEmax nas posições sentada e deitada, totalizando 320 medidas. Os dados foram comparados pelo teste de Wilcoxon (pINTRODUCCIÓN: las presiones inspiratorias (PImáx y espiratorias (PEmáx máximas constituyen un método simple y no invasivo para evaluar la fuerza de los músculos respiratorios, y ayudan a identificar la debilidad de los músculos respiratorios presente en diferentes enfermedades y situaciones clínicas, como la tetraplejía. Objetivo: evaluar el número de maniobras necesarias para llegar a las presiones máximas en pacientes con tetraplejía. MÉTODOS: fueron incluidos ocho pacientes con tetraplejía (siete hombres, con edad media de 37,8±11,96 años y diagnóstico de lesión cervical raquis medular completa, a lo que se le realizo diez mediciones de PImáx y PEmáx en posición sentado y acostado, totalizando 320 mediciones. Los datos fueron comparados por el test de Wilcoxon (pINTRODUCTION: maximum inspiratory (PImax and expiratory (PEmax pressures are a simple non-invasive method for evaluation of respiratory muscle strength that helps in the identification of muscle weakness, usually present in several diseases and clinical situations, such as quadriplegia. Objective: to assess the number of maneuvers needed to achieve maximum pressures in patients with quadriplegia. METHODS: eight quadriplegic patients

  3. Water Pressure Distribution on a Flying Boat Hull

    Science.gov (United States)

    Thompson, F L

    1931-01-01

    This is the third in a series of investigations of the water pressures on seaplane floats and hulls, and completes the present program. It consisted of determining the water pressures and accelerations on a Curtiss H-16 flying boat during landing and taxiing maneuvers in smooth and rough water.

  4. Computing and Visualizing Reachable Volumes for Maneuvering Satellites

    Energy Technology Data Exchange (ETDEWEB)

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

    2011-09-11

    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.

  5. 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

  6. Command shaping for residual vibration free crane maneuvers

    Energy Technology Data Exchange (ETDEWEB)

    Parker, G.G.; Petterson, B.; Dohrmann, C.; Robinett, R.D.

    1995-07-01

    Cranes used in the construction and transportation industries are generally devices with multiple degrees of freedom including variable load-line length, variable jib length (usually via a trolley), and variable boom angles. Point-to-point payload maneuvers using cranes are performed so as not to excite the spherical pendulum modes of their cable and payload assemblies. Typically, these pendulum modes, although time-varying, exhibit low frequencies. Current crane maneuvers are therefore performed slowly contributing to high construction and transportation costs. This investigation details a general method for applying command shaping to various multiple degree of freedom cranes such that the payload moves to a specified point without residual oscillation. A dynamic programming method is used for general command shaping for optimal maneuvers. Computationally, the dynamic programming approach requires order M calculations to arrive at a solution, where M is the number of discretizations of the input commands. This feature is exploited for the crane command shaping problem allowing for rapid calculation of command histories. Fast generation of commands is a necessity for practical use of command shaping for the applications described in this work. These results are compared to near-optimal solutions where the commands are linear combinations of acceleration pulse basis functions. The pulse shape is required due to hardware requirements. The weights on the basis functions are chosen as the solution to a parameter optimization problem solved using a Recursive Quadratic Programming technique. Simulation results and experimental verification for a variable load-line length rotary crane are presented using both design procedures.

  7. Volunteer kinematics and reaction in lateral emergency maneuver tests.

    Science.gov (United States)

    Rooij, L van; Elrofai, H; Philippens, M M G M; Daanen, H A M

    2013-11-01

    It is important to understand human kinematics and muscle activation patterns in emergency maneuvers for the design of safety systems and for the further development of human models. The objective of this study was to quantify kinematic behavior and muscle activation in simulated steering tests in several realistic conditions. In total 108 tests were performed with 10 volunteers undergoing purely lateral maneuvers at 5 m/s^2 deceleration or simulated lane change maneuvers at 5 m/s^2 peak acceleration and peak yaw velocity of 25 °/s. Test subjects were seated on a rigid seat and restrained by a 4-point belt with retractor. Driver subjects were instructed to be relaxed or braced and to hold the steering wheel while passenger subjects were instructed to put their hands on their thighs. Subjects were instrumented with photo markers that were tracked with 3D high- speed stereo cameras and with electromyography (EMG) electrodes on 8 muscles. Corridors of head displacement, pitch and roll and displacement of T1, shoulder, elbow, hand and knee were created representing mean response and standard deviation of all subjects. In lane change tests for the passenger configuration significant differences were observed in mean peak of head left lateral displacement between the relaxed and the braced volunteers, i.e. 171 mm (σ=58, n=21) versus 121 mm (σ=46, n=17), respectively. Sitting in a relaxed position led to significantly lower muscle activity of the neck muscles. It was concluded that significantly more upper body motion and lower muscle activity was observed for relaxed subjects than for braced subjects.

  8. 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

  9. OTHR Spectrum Reconstruction of Maneuvering Target with Compressive Sensing

    Directory of Open Access Journals (Sweden)

    Yinghui Quan

    2014-01-01

    Full Text Available High-frequency (HF over-the-horizon radar (OTHR works in a very complicated electromagnetic environment. It usually suffers performance degradation caused by transient interference. In this paper, we study the transient interference excision and full spectrum reconstruction of maneuvering targets. The segmental subspace projection (SP approach is applied to suppress the clutter and locate the transient interference. After interference excision, the spectrum is reconstructed from incomplete measurements via compressive sensing (CS by using a redundant Fourier-chirp dictionary. An improved orthogonal matching pursuit (IOMP algorithm is developed to solve the sparse decomposition optimization. Experimental results demonstrate the effectiveness of the proposed methods.

  10. Heimlich's maneuver-assisted bronchoscopic removal of airway foreign body

    OpenAIRE

    Solanki, Sohan Lal; Bansal, Shivendu; Khare, Arvind; Jain, Amit

    2011-01-01

    Aspiration of foreign bodies (FBs) by children can lead to serious illness and sometimes even death. Bronchoscopic removal of the FB is necessary to prevent from any catastrophic event. Sometimes bronchoscopic removal is not possible due to the larger size of the FB, sharp FB, or long duration FB. Tracheostomy is normally used for the removal of such FBs. The aim of this case report is to highlight the use of Heimlich maneuver for the removal of such FBs before opting invasive procedures. In ...

  11. Robust control for snake maneuver design of missile

    Science.gov (United States)

    Kun, Ya; Chen, Xin; Li, Chuntao

    2017-01-01

    For the performance of missile with high Mach number and strongly nonlinear dynamics, this paper uses robust control to design maneuver controller. Robust servomechanism linear quadratic regulator (RSLQR) control is used to form the inner loop and proportional-plus-integral (PI) control is used to provide yawing tracking with no error. Contrast simulations under three types of deviation have been done to confirm robustness of the RSLQR-plus-PI control. Simulation results shows that RSLQR-plus-PI control would resist the disturbance and maintain the properties of the controller, guarantee the robustness and stability of missile more effectively than pure PI control.

  12. 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.

  13. NONLINEAR DYNAMICS OF A CRACKED ROTOR IN A MANEUVERING AIRCRAFT

    Institute of Scientific and Technical Information of China (English)

    LIN Fu-sheng 林富生; MENG Guang 孟光; Eric Hahn

    2004-01-01

    The nonlinear dynamics of a cracked rotor system in an aircraft maneuvering with constant velocity or acceleration was investigated. The influence of the aircraft climbing angle on the cracked rotor system response is of particular interest and the results show that the climbing angle can markedly affect the parameter range for bifurcation, for quasi-periodic response and for chaotic response as well as for system stability. Aircraft acceleration is also shown to significantly affect the nonlinear behavior of the cracked rotor system, illustrating the possibility for on-line rotor crack fault diagnosis.

  14. Maneuvering Vehicle Tracking Based on Multi-sensor Fusion

    Institute of Scientific and Technical Information of China (English)

    CHENYing; HANChong-Zhao

    2005-01-01

    Maneuvering targets tracking is a fundamental task in intelligent vehicle research. This paper focuses on the problem of fusion between radar and image sensors in targets tracking. In order to improve positioning accuracy and narrow down the image working area, a novel method that integrates radar filter with image intensity is proposed to establish an adaptive vision window.A weighted Hausdorff distance is introduced to define the functional relationship between image and model projection, and a modified simulated annealing algorithm is used to find optimum orientation parameter. Furthermore, the global state is estimated, which refers to the distributed data fusion algorithm. Experiment results show that our method is accurate.

  15. Rupture of the lesser gastric curvature after a Heimlich maneuver.

    Science.gov (United States)

    Gallardo, A; Rosado, R; Ramírez, D; Medina, P; Mezquita, S; Sánchez, J

    2003-09-01

    We present a case of lesser gastric curvature injury after a Heimlich maneuver due to obstruction of the breathing tract that was repaired by laparoscopic surgery. A patient with perforation of the lesser gastric curvature as a result of closed abdominal traumatism was operated on using the laparoscopic approach with the use of four trocars as work openings. With this technique, the diagnosis was confirmed, the injury repaired, and the abdominal cavity washed. The postoperative period was favorable and the patient was released from the hospital on day 7 without any complications. Laparoscopic surgery can be technically reproduced in the treatment of gastric injury as a result of closed abdominal traumatism.

  16. The Orbital Maneuvering Vehicle Training Facility visual system concept

    Science.gov (United States)

    Williams, Keith

    1989-01-01

    The purpose of the Orbital Maneuvering Vehicle (OMV) Training Facility (OTF) is to provide effective training for OMV pilots. A critical part of the training environment is the Visual System, which will simulate the video scenes produced by the OMV Closed-Circuit Television (CCTV) system. The simulation will include camera models, dynamic target models, moving appendages, and scene degradation due to the compression/decompression of video signal. Video system malfunctions will also be provided to ensure that the pilot is ready to meet all challenges the real-world might provide. One possible visual system configuration for the training facility that will meet existing requirements is described.

  17. Sequential Probability Ratio Test for Collision Avoidance Maneuver Decisions

    Science.gov (United States)

    Carpenter, J. Russell; Markley, F. Landis

    2010-01-01

    When facing a conjunction between space objects, decision makers must chose whether to maneuver for collision avoidance or not. We apply a well-known decision procedure, the sequential probability ratio test, to this problem. We propose two approaches to the problem solution, one based on a frequentist method, and the other on a Bayesian method. The frequentist method does not require any prior knowledge concerning the conjunction, while the Bayesian method assumes knowledge of prior probability densities. Our results show that both methods achieve desired missed detection rates, but the frequentist method's false alarm performance is inferior to the Bayesian method's

  18. 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.

  19. OMV: A simplified mathematical model of the orbital maneuvering vehicle

    Science.gov (United States)

    Teoh, W.

    1984-01-01

    A model of the orbital maneuvering vehicle (OMV) is presented which contains several simplications. A set of hand controller signals may be used to control the motion of the OMV. Model verification is carried out using a sequence of tests. The dynamic variables generated by the model are compared, whenever possible, with the corresponding analytical variables. The results of the tests show conclusively that the present model is behaving correctly. Further, this model interfaces properly with the state vector transformation module (SVX) developed previously. Correct command sentence sequences are generated by the OMV and and SVX system, and these command sequences can be used to drive the flat floor simulation system at MSFC.

  20. Development of a Smooth Trajectory Maneuver Method to Accommodate the Ares I Flight Control Constraints

    Science.gov (United States)

    Pinson, Robin M.; Schmitt, Terri L.; Hanson, John M.

    2008-01-01

    Six degree-of-freedom (DOF) launch vehicle trajectories are designed to follow an optimized 3-DOF reference trajectory. A vehicle has a finite amount of control power that it can allocate to performing maneuvers. Therefore, the 3-DOF trajectory must be designed to refrain from using 100% of the allowable control capability to perform maneuvers, saving control power for handling off-nominal conditions, wind gusts and other perturbations. During the Ares I trajectory analysis, two maneuvers were found to be hard for the control system to implement; a roll maneuver prior to the gravity turn and an angle of attack maneuver immediately after the J-2X engine start-up. It was decided to develop an approach for creating smooth maneuvers in the optimized reference trajectories that accounts for the thrust available from the engines. A feature of this method is that no additional angular velocity in the direction of the maneuver has been added to the vehicle after the maneuver completion. This paper discusses the equations behind these new maneuvers and their implementation into the Ares I trajectory design cycle. Also discussed is a possible extension to adjusting closed-loop guidance.

  1. Orbital Maneuvers Using Low Thrust to Place a Satellite in a Constellation

    Directory of Open Access Journals (Sweden)

    Vivian Martins Gomes

    2007-01-01

    Full Text Available This paper considers the problem of low thrust suboptimal maneuvers to insert a satellite in a constellation. It is assumed that a satellite constellation is given with all the Keplerian elements of the satellite members having known values. Then, it is necessary to maneuver a new satellite from a parking orbit to its position in the constellation. The control available to perform this maneuver is the application of a low thrust to the satellite and the objective is to perform this maneuver with minimum fuel consumption.

  2. Development of control laws for a flight test maneuver autopilot for an F-15 aircraft

    Science.gov (United States)

    Alag, G. S.; Duke, E. L.

    1985-01-01

    An autopilot can be used to provide precise control to meet the demanding requirements of flight research maneuvers with high-performance aircraft. The development of control laws within the context of flight test maneuver requirements is discussed. The control laws are developed using eigensystem assignment and command generator tracking. The eigenvalues and eigenvectors are chosen to provide the necessary handling qualities, while the command generator tracking enables the tracking of a specified state during the maneuver. The effectiveness of the control laws is illustrated by their application to an F-15 aircraft to ensure acceptable aircraft performance during a maneuver.

  3. The Valsalva maneuver duration during labor expulsive stage: repercussions on the maternal and neonatal birth condition Duração da manobra de Valsalva durante o período expulsivo do parto: repercussões maternas e nas condições neonatais de nascimento

    Directory of Open Access Journals (Sweden)

    Andrea Lemos

    2011-02-01

    Full Text Available OBJECTIVES: This cross-sectional study was designed to examine the effects of the Valsalva Maneuver (VM and its duration on the acid- base equilibrium of the neonate and its maternal repercussions during the expulsive stage of labor, after standard breathing and pushing instructions were given. METHODS: A convenience sample of women with low risk pregnancy (n=33; mean age 22.5±3.7y and gestational age 38.1±1.12wks and their newborns were studied during the expulsive stage of vaginal labor. Coaching consisted of standard recommendations for breathing including prolonged VMs coordinated with pushing. Maternal outcomes included the need for uterus fundal pressure maneuver and episiotomy, perineal trauma and posture. Neonatal outcomes included blood gases sampled from the umbilical cord, and Apgar scores. Data were analyzed with the Fisher's exact test, chi-square test, and Pearson correlation coefficient. RESULTS: None of the maternal outcomes were associated with VM duration. With respect to neonatal outcomes, increased VM duration was associated with reduced venous umbilical pH (r=-0.40; p=0.020, venous base excess (r=-0.42; p=0.014 and with arterial base excess (r=-0.36; p=0.043. Expulsive stage time was negatively associated with umbilical venous and arterial pH. CONCLUSIONS: VM duration during fetal expulsion in labor negatively affects fetal acid-base equilibrium and potentially the wellbeing of the neonate. Our results support the need to consider respiratory strategies during labor, to minimize potential risk to the mother and neonate.OBJETIVOS: O presente estudo de corte transversal teve como objetivo avaliar os efeitos da Manobra de Valsalva (MV e sua duração no equilíbrio ácido-básico fetal e nas repercussões maternas durante o período expulsivo do parto, após instrução respiratória padronizada. MÉTODOS: Uma amostra de conveniência em gestantes de baixo risco (n=33, média de idade 22,5±3.7 anos e idade gestacional 38.1

  4. Drivers’ Visual Search Patterns during Overtaking Maneuvers on Freeway

    Directory of Open Access Journals (Sweden)

    Wenhui Zhang

    2016-11-01

    Full Text Available Drivers gather traffic information primarily by means of their vision. Especially during complicated maneuvers, such as overtaking, they need to perceive a variety of characteristics including the lateral and longitudinal distances with other vehicles, the speed of others vehicles, lane occupancy, and so on, to avoid crashes. The primary object of this study is to examine the appropriate visual search patterns during overtaking maneuvers on freeways. We designed a series of driving simulating experiments in which the type and speed of the leading vehicle were considered as two influential factors. One hundred and forty participants took part in the study. The participants overtook the leading vehicles just like they would usually do so, and their eye movements were collected by use of the Eye Tracker. The results show that participants’ gaze durations and saccade durations followed normal distribution patterns and that saccade angles followed a log-normal distribution pattern. It was observed that the type of leading vehicle significantly impacted the drivers’ gaze duration and gaze frequency. As the speed of a leading vehicle increased, subjects’ saccade durations became longer and saccade angles became larger. In addition, the initial and destination lanes were found to be key areas with the highest visual allocating proportion, accounting for more than 65% of total visual allocation. Subjects tended to more frequently shift their viewpoints between the initial lane and destination lane in order to search for crucial traffic information. However, they seldom directly shifted their viewpoints between the two wing mirrors.

  5. 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.

  6. Aeroelastic optimization design for wing with maneuver load uncertainties

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    An aeroelastic optimization design methodology for air vehicle considering the uncertainties in maneuver load conditions is presented and applied to a structural design process of low-aspect-ratio wing. An aerodynamic load correction model is developed and used to predict the critical load conditions with the perturbations of theoretical linear aerodynamic forces and experimental aerodynamic forces from wind-tunnel test, when concerning the uncertainties in use of theoretical linear and experimental aerodynamic forces. Three objective functions of critical loads are defined. The load evaluations for three wing sections are investigated in four characteristic maneuvers, and the most critical load conditions are confirmed by using the sequential quadratic programming method. On this basis, the aeroelastic optimization design employing the genetic-gradient hybrid algorithm is conducted, in which the objective is to minimize structural mass subject to the constraints of stress, deformation and flutter speed. The resulting optimal structure is heavier than the one simply based on the theoretical linear or experimental aerodynamic forces. However, it is more robust when encountering the critical load conditions in actual flight due to the consideration of uncertainties in aerodynamic forces in the early design phase, thereby, the risk of structural redesign can be reduced.

  7. Control and dynamics of a flexible spacecraft during stationkeeping maneuvers

    Science.gov (United States)

    Liu, D.; Yocum, J.; Kang, D. S.

    1991-01-01

    A case study of a spacecraft having flexible solar arrays is presented. A stationkeeping attitude control mode using both earth and rate gyro reference signals and a flexible vehicle dynamics modeling and implementation is discussed. The control system is designed to achieve both pointing accuracy and structural mode stability during stationkeeping maneuvers. Reduction of structural mode interactions over the entire mode duration is presented. The control mode using a discrete time observer structure is described to show the convergence of the spacecraft attitude transients during Delta-V thrusting maneuvers without preloading thrusting bias to the onboard control processor. The simulation performance using the three axis, body stabilized nonlinear dynamics is provided. The details of a five body dynamics model are discussed. The spacecraft is modeled as a central rigid body having cantilevered flexible antennas, a pair of flexible articulated solar arrays, and to gimballed momentum wheels. The vehicle is free to undergo unrestricted rotations and translations relative to inertial space. A direct implementation of the equations of motion is compared to an indirect implementation that uses a symbolic manipulation software to generate rigid body equations.

  8. State estimators for tracking sharply-maneuvering ground targets

    Science.gov (United States)

    Visina, Radu S.; Bar-Shalom, Yaakov; Willett, Peter

    2017-05-01

    This paper presents an algorithm, based on the Interacting Multiple Model Estimator, that can be used to track the state of kinematic point targets, moving in two dimensions, that are capable of making sharp heading maneuvers over short periods of time, such as certain ground vehicles moving in an open field. The targets are capable of up to 60 °/s turn rates, while polar measurements are received at 1 Hz. We introduce the Non-Zero Mean, White Noise Turn-Rate IMM (IMM-WNTR) that consists of 3 modes based on a White Noise Turn Rate (WNTR) kinematic model that contains additive, white, Gaussian turn rate process noises. Two of the modes are considered maneuvering modes, and they have opposite (left/right), non-zero mean turn rate input noise. The need for non-zero mean turn rate process noise is explained, and Monte Carlo simulations compare this novel design to the traditional (single-mode) White Noise Acceleration Kalman Filter (WNA KF) and the two-mode White Noise Acceleration/Nearly-Coordinated Turn Rate IMM (IMM-CT). Results show that the IMM-WNTR filter achieves better accuracy and real-time consistency between expected error and actual error as compared to the (single-mode) WNA KF and the IMM-CT in all simulated scenarios, making it a very accurate state estimator for targets with sharp coordinated turn capability in 2D.

  9. Muscular Control of Turning and Maneuvering in Jellyfish Bells

    Science.gov (United States)

    Hoover, Alexander; Miller, Laura; Griffith, Boyce

    2014-11-01

    Jellyfish represent one of the earliest and simplest examples of swimming by a macroscopic organism. Contractions of an elastic bell that expels water are driven by coronal swimming muscles. The re-expansion of the bell is passively driven by stored elastic energy. A current question in jellyfish propulsion is how the underlying neuromuscular organization of their bell allows for maneuvering. Using an immersed boundary framework, we will examine the mechanics of swimming by incorporating material models that are informed by the musculature present in jellyfish into a model of the elastic jellyfish bell in three dimensions. The fully-coupled fluid structure interaction problem is solved using an adaptive and parallelized version of the immersed boundary method (IBAMR). We then use this model to understand how variability in the muscular activation patterns allows for complicated swimming behavior, such as steering. We will compare the results of the simulations with the actual turning maneuvers of several species of jellyfish. Numerical flow fields will also be compared to those produced by actual jellyfish using particle image velocimetry (PIV).

  10. Use of a tantalum-178 generator and a multiwire gamma camera to study the effect of the Mueller maneuver on left ventricular performance: comparison to hemodynamics and single photon emission computed tomography perfusion patterns.

    Science.gov (United States)

    Gioia, G; Lin, B; Katz, R; DiMarino, A J; Ogilby, J D; Cassel, D; DePace, N L; Heo, J; Iskandrian, A S

    1995-11-01

    During the Mueller maneuver, there is a decrease in intrathoracic pressure and an increase in transmural left ventricular pressure. The changes in loading conditions cause transient left ventricular dysfunction. This study examined the effects of the Mueller maneuver on left ventricular performance using tantalum (Ta)-178 (half-life 9.3 min) and a multiwire gamma camera. First-pass radionuclide angiograms were obtained at baseline and during Mueller maneuver in 41 patients aged 58 +/- 10 years. In 34 patients, stress single photon emission computed tomography (SPECT) myocardial perfusion imaging with thallium-201 or sestamibi was also performed. Hemodynamic measurements during the Mueller maneuver (n = 10) showed a decrease in systemic pressure (139 +/- 25 mm Hg vs 123 +/- 24 mm Hg, p or = 5%) in 17 patients (group 2) (55% +/- 13% vs 40% +/- 16%, p = 0.001). The stress SPECT images showed no or only fixed defects in 11 (65%) patients in group 1 and 3 (18%) patients in group 2 (p = 0.02), and reversible defects in 6 (35%) patients in group 1 and 14 (82%) patients in group 2 (p = 0.04).(ABSTRACT TRUNCATED AT 250 WORDS)

  11. Teaching Cardiac Autonomic Function Dynamics Employing the Valsalva (Valsalva-Weber) Maneuver

    Science.gov (United States)

    Junqueira, Luiz Fernando, Jr.

    2008-01-01

    In this report, a brief history of the Valsalva (Valsalva-Weber) maneuver is outlined, followed by an explanation on the use of this approach for the evaluation of cardiac autonomic function based on underlying heart rate changes. The most important methodological and interpretative aspects of the Valsalva-Weber maneuver are critically updated,…

  12. 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.

  13. When do drivers abort an overtaking maneuver 5 on two-lane rural roads

    NARCIS (Netherlands)

    Farah, H.

    2016-01-01

    Overtaking on two-lane roads is a complex driving maneuver. Drivers who desire to overtake a lead vehicle need to evaluate the available gaps in the opposite direction and accept a sufficient gap to successfully complete the overtaking maneuver. However, often drivers realize that the gap they acce

  14. Teaching Cardiac Autonomic Function Dynamics Employing the Valsalva (Valsalva-Weber) Maneuver

    Science.gov (United States)

    Junqueira, Luiz Fernando, Jr.

    2008-01-01

    In this report, a brief history of the Valsalva (Valsalva-Weber) maneuver is outlined, followed by an explanation on the use of this approach for the evaluation of cardiac autonomic function based on underlying heart rate changes. The most important methodological and interpretative aspects of the Valsalva-Weber maneuver are critically updated,…

  15. 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.

  16. UAS Well Clear Recovery Against Non-Cooperative Intruders Using Vertical Maneuvers

    Science.gov (United States)

    Cone, Andrew; Thipphavong, David; Lee, Seung Man; Santiago, Confesor

    2017-01-01

    This paper documents a study that drove the development of a mathematical expression in the minimum operational performance standards (MOPS) of detect-and-avoid (DAA) systems for unmanned aircraft systems (UAS). This equation describes the conditions under which vertical maneuver guidance could be provided during recovery of well clear separation with a non-cooperative VFR aircraft in addition to horizontal maneuver guidance. Although suppressing vertical maneuver guidance in these situations increased the minimum horizontal separation from 500 to 800 feet, the maximum severity of loss of well clear increased in about 35 of the encounters compared to when a vertical maneuver was preferred and allowed. Additionally, analysis of individual cases led to the identification of a class of encounter where vertical rate error had a large effect on horizontal maneuvers due to the difficulty of making the correct left-right turn decision: crossing conflict with intruder changing altitude. These results supported allowing vertical maneuvers when UAS vertical performance exceeds the relative vertical position and velocity accuracy of the DAA tracker given the current velocity of the UAS and the relative vertical position and velocity estimated by the DAA tracker. Looking ahead, these results indicate a need to improve guidance algorithms by utilizing maneuver stability and near mid-air collision risk when determining maneuver guidance to regain well clear separation.

  17. 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.

  18. Wild2 approach maneuver strategy used for Stardust spacecraft (extended abstract)

    Science.gov (United States)

    Bhar, Ramachandra S.; Williams, Kenneth E.; Helfrich, Clifford E.; Kennedy, Brian M.; Carranza, Eric

    2004-01-01

    Stardust, NASA's first dedicated sample return mission to a comet, successfully flew through the comet dust around Wold2 on January 2, 2004. The spacecraft flew within 236 km of the comet, meeting the mission requirement of 250+/- 50 km on flyby distance. Stardust collected dust particles and took several images of the comet while flying close to Wild2. The spacecraft will return to earth with the comet samples on January 15, 2006. To accomplish the above objective, a large Deep Space Maneuver (DSM#) was implemented during June 17 and 18, 2003 and a series of Trajectory Correction Maneuvers (TCMs) were also implemented during the 30 days prior to encounter. Both maneuver design and executions were influenced by number of factors including the small body ephemeris uncertainty, predictability of small forces arising from 3-axis attitude limit cycling and spacecraft slews. Maneuver design processes, including contingency plans, and maneuver performance characteristics, are discussed in this paper.

  19. An adaptive attitude algorithm based on a current statistical model for maneuvering acceleration

    Directory of Open Access Journals (Sweden)

    Menglong Wang

    2017-02-01

    Full Text Available A current statistical model for maneuvering acceleration using an adaptive extended Kalman filter (CS-MAEKF algorithm is proposed to solve problems existing in conventional extended Kalman filters such as large estimation error and divergent tendencies in the presence of continuous maneuvering acceleration. A membership function is introduced in this algorithm to adaptively modify the upper and lower limits of loitering vehicles’ maneuvering acceleration and for real-time adjustment of maneuvering acceleration variance. This allows the algorithm to have superior static and dynamic performance for loitering vehicles undergoing different maneuvers. Digital simulations and dynamic flight testing show that the yaw angle accuracy of the algorithm is 30% better than conventional algorithms, and pitch and roll angle calculation precision is improved by 60%. The mean square deviation of heading and attitude angle error during dynamic flight is less than 3.05°. Experimental results show that CS-MAEKF meets the application requirements of miniature loitering vehicles.

  20. Ship Trajectory Control Optimization in Anti-collision Maneuvering

    Directory of Open Access Journals (Sweden)

    Jinfen Zhang

    2013-03-01

    Full Text Available A lot of attentions are being paid to ship’s intelligent anti-collision by researchers. Several solutions have been introduced to find an optimum trajectory for ship, such as Game Theory, Genetic or Evolutionary Algorithms and so on. However, ship’s maneuverability should be taken into consideration before their real applications. This paper focuses on ship’s trajectory control problem in anti-collision maneuvering. At first, a simple linear ship maneuverability model is introduced to simulate its movement under different speed and rudder angle. After that, ship’s trajectory control is studied by considering the duration of rudder, operation distance to turning points, and maximum angular velocity. The details for algorithm design are also introduced. By giving some restrictions according to the requirements from COLREGs, the intervals for rudder angle in different circumstances can be determined by the curves. The results can give very meaningful guidance for seafarers when making decisions.

  1. Slew maneuver dynamics of the Spacecraft Control Laboratory experiment

    Science.gov (United States)

    Kakad, Y. P.

    1987-01-01

    Mathematical expressions for slew maneuver dynamics are presented. The total kinetic energy expression of the system is given as T = T(0) + T(1) + T(2), where T(0), T(1), and T(2) refer to the kinetic energies of the shuttle, the flexible beam, and the tip mass (the reflector), respectively. The specific equations for each of these are defined and integrated into the total energy expression. Using the chain rule in the Lagrange equations and an expression allowing the transformation of the orbiter angular velocity from the inertial frame to the body-fixed frame, the rotational equations are obtained. Finally, the vibration equations for the beam are derived, again using the Lagrange equations.

  2. 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.

  3. 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.

  4. Orbital Maneuvering Vehicle (OMV) missions applications and systems requirements

    Science.gov (United States)

    Huber, W. G.; Cramblit, D. C.

    The routine delivery of large payloads to low earth orbit has become a reality with the Space Transportation System (STS). However, once earth orbit has been achieved, orbit transfer operations represent an inefficient use of the Space Shuttle. The Orbital Maneuvering Vehicle (OMV) will add a new and needed dimension to STS capabilities. Utilized in a reusable manner, the OMV is needed to deliver and retrieve satellites to and from orbital altitudes or inclinations beyond the practical limits of the Space Shuttle and to support basic Space Station activities. The initial OMV must also be designed to permit the addition of future mission kits to support the servicing, module changeout, or refueling of satellites in Low Earth Orbit (LEO) and Geostationary Earth Orbit (GEO), and the retrieval and deorbit of space debris. This paper addresses the mission needs along with the resulting performance implications, design requirements and operational capabilities imposed on the OMV planned for use in the late 1980s.

  5. Orbit Maneuver of Spinning Tether via Tidal Force

    CERN Document Server

    Baoyin, Hexi; Li, Junfeng

    2014-01-01

    Recently, the spinning tethered system is regarded as a typical and fundamental space structure attracting great interest of the aerospace engineers, and has been discussed primarily for specific space missions in past decades, including on-orbit capture and propellantless orbit transfer etc. The present work studies the dynamical behaviours of a fast spinning tethered binary system under central gravitational field, and derives principles of the basic laws of orbital maneuver. Considering the characteristics of coupled librational and orbital motions, an averaging method is introduced to deal with the slow-fast system equation, thus a definite equivalent model is derived. The general orbit motion is completely determined analytically, including the orbit geometry, periodicity, conversations and moving region etc. Since the possibility of orbit control using tether reaction has been proved by previous studies, special attention is paid to the transportation mode of angular momentum and mechanical energy betwe...

  6. Fogarty Maneuver to Restore Coronary Flow in ST-Segment Elevation Myocardial Infarction: Desperate Times Call for Desperate Measures.

    Science.gov (United States)

    Larralde, Mark J; Afzal, Ashwad; Brener, Sorin J

    2016-01-01

    Nonatherosclerotic embolism is a rare cause (4%-7%) of coronary occlusion in ST-segment elevation myocardial infarction (STEMI) patients, approximately half of which occur in inadequately anticoagulated patients with prosthetic valves. We report a rare case of a patient with severe rheumatic heart disease and 3 mechanical valves presenting with STEMI that was successfully managed by Fogarty maneuver thrombus extraction after failed thrombus aspiration and balloon angioplasty. A 56-year-old woman presented with an acute anterior STEMI and Killip class III heart failure. She had severe rheumatic heart disease with mechanical tricuspid, mitral and aortic valve prostheses, and atrial fibrillation on warfarin anticoagulation. The international normalized ratio on admission was 1.1. Emergency coronary angiography revealed normal right and circumflex coronary arteries and a total occlusion in the mid left anterior descending artery with a meniscus appearance. Multiple attempts at thrombus aspiration and balloon angioplasty failed to restore flow in the left anterior descending artery. Ultimately, a Fogarty maneuver using a compliant balloon inflated at a low pressure was performed successfully, removing the thrombus into the guiding catheter. There was Thrombolysis in Myocardial Infarction flow grade 3 and near-normal myocardial blush at the end of the procedure. Signs and symptoms of heart failure resolved quickly.

  7. 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.

  8. The repeated sit-to-stand maneuver is a superior method for cardiac baroreflex assessment: a comparison with the modified Oxford method and Valsalva maneuver.

    Science.gov (United States)

    Horsman, H M; Tzeng, Y C; Galletly, D C; Peebles, K C

    2014-12-01

    Baroreflex assessment has diagnostic and prognostic utility in the clinical and research environments, and there is a need for a reliable, simple, noninvasive method of assessment. The repeated sit-to-stand method induces oscillatory changes in blood pressure (BP) at a desired frequency and is suitable for assessing dynamic baroreflex sensitivity (BRS). However, little is known about the reliability of this method and its ability to discern fundamental properties of the baroreflex. In this study we sought to: 1) evaluate the reliability of the sit-to-stand method for assessing BRS and compare its performance against two established methods (Oxford method and Valsalva maneuver), and 2) examine whether the frequency of the sit-to-stand method influences hysteresis. Sixteen healthy participants underwent three trials of each method. For the sit-to-stand method, which was performed at 0.1 and 0.05 Hz, BRS was quantified as an integrated response (BRSINT) and in response to falling and rising BP (BRSDOWN and BRSUP, respectively). Test retest reliability was assessed using the intraclass correlation coefficient (ICC). Irrespective of frequency, the ICC for BRSINT during the sit-to-stand method was ≥0.88. The ICC for a rising BP evoked by phenylephrine (PEGAIN) in the Oxford method was 0.78 and ≤0.5 for the remaining measures. During the sit-to-stand method, hysteresis was apparent in all participants at 0.1 Hz but was absent at 0.05 Hz. These findings indicate the sit-to-stand method is a statistically reliable BRS assessment tool and suitable for the examination of baroreflex hysteresis. Using this approach we showed that baroreflex hysteresis is a frequency-dependent phenomenon.

  9. Precision Closed-Loop Orbital Maneuvering System Design and Performance for the Magnetospheric Multiscale Formation

    Science.gov (United States)

    Chai, Dean J.; Queen, Steven Z.; Placanica, Samuel J.

    2015-01-01

    NASAs Magnetospheric Multiscale (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. Momentum balance, hydrodynamic impulse and choreography in rapidly maneuvering live fish

    Science.gov (United States)

    Epps, B. P.; Techet, A. H.

    2006-11-01

    It is well known that swimming fish can swim circles around underwater vehicles when it comes to maneuvering performance. A typical underwater vehicle sweeps a circular arc, about ten vehicle lengths in diameter, and this requires about 15 times the amount of time it takes for the vehicle to drive one body length. In contrast, a fish, such as the Danio aequipinnatus, can turn in a space that is approximately one third of its body length, and it requires about half the time it takes to swim one body length. High-speed Particle Imaging Velocimetry (PIV) is used to quantify the impulse imparted to the fluid during a maneuver which is compared to the change in momentum of the fish during the maneuver. In order to model the impulse of the fluid, we make the assumption that the wake may be modeled as an axisymmetric vortex ring. The evidence that this is an appropriate model comes from a recent study of rapidly maneuvering flapping foils. Our PIV results show that the fish in fact generates two such wakes, one generated by the tail and shed at the conclusion of stage one of the maneuver and the other generated by the mid-section of the body and shed at the conclusion of stage two of the maneuver. Both of these vertical impulses are required to balance the momentum change of the fish from its initial swimming trajectory to its final swimming trajectory in a classical C-shaped maneuver.

  11. Precise orbit determination of a maneuvered GEO satellite using CAPS ranging data

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    Wheel-off-loadings and orbital maneuvers of the GEO satellite result in additional accelerations to the satellite itself. Complex and difficult to model, these time varying accelerations are an important error source of precise orbit determination (POD). In most POD practices, only non-maneuver orbital arcs are treated. However, for some applications such as satellite navigation RDSS services, uninterrupted orbital ephemeris is demanded, requiring the development of POD strategies to be processed both during and after an orbital maneuver. We in this paper study the POD for a maneuvered GEO satellite, using high precision and high sampling rate ranging data obtained with Chinese Area Positioning System (CAPS). The strategy of long arc POD including maneuver arcs is studied by using telemetry data to model the maneuver thrust process. Combining the thrust and other orbital perturbations, a long arc of 6 days’ CAPS ranging data is analyzed. If the telemetry data are not available or contain significant errors, attempts are made to estimate thrusting parameters using CAPS ranging data in the POD as an alternative to properly account for the maneuver. Two strategies achieve reasonably good data fitting level in the tested arc with the maximal position difference being about 20 m.

  12. Precise orbit determination of a maneuvered GEO satellite using CAPS ransing data

    Institute of Scientific and Technical Information of China (English)

    HUANG Yong; HU XiaoGong; HUANG Cheng; YANG QiangWen; JIAO WenHai

    2009-01-01

    Wheel-off-loadings and orbital maneuvers of the GEO satellite result in additional accelerations to the satellite itself.Complex and difficult to model,these time varying accelerations are an important error source of precise orbit determination (POD).In most POD practices,only non-maneuver orbital arcs are treated.However,for some applications such as satellite navigation RDSS services,uninterrupted orbital ephemeris is demanded,requiring the development of POD strategies to be processed both during and after an orbital maneuver.We in this paper study the POD for a maneuvered GEO satellite,using high precision and high sampling rate ranging data obtained with Chinese Area Positioning System (CAPS).The strategy of long arc POD including maneuver arcs is studied by using telemetry data to model the maneuver thrust process.Combining the thrust and other orbital perturbations,a long arc of 6 days' CAPS ranging data is analyzed.If the telemetry data are not available or contain significant errors,attempts are made to estimate thrusting parameters using CAPS ranging data in the POD as an alternative to properly account for the maneuver.Two strategies achieve reasonably good data fitting level in the tested arc with the maximal position difference being about 20m.

  13. Precise orbit determination of a maneuvered GEO satellite using CAPS ranging data

    Science.gov (United States)

    Huang, Yong; Hu, Xiaogong; Huang, Cheng; Yang, Qiangwen; Jiao, Wenhai

    2009-03-01

    Wheel-off-loadings and orbital maneuvers of the GEO satellite result in additional accelerations to the satellite itself. Complex and difficult to model, these time varying accelerations are an important error source of precise orbit determination (POD). In most POD practices, only non-maneuver orbital arcs are treated. However, for some applications such as satellite navigation RDSS services, uninterrupted orbital ephemeris is demanded, requiring the development of POD strategies to be processed both during and after an orbital maneuver. We in this paper study the POD for a maneuvered GEO satellite, using high precision and high sampling rate ranging data obtained with Chinese Area Positioning System (CAPS). The strategy of long arc POD including maneuver arcs is studied by using telemetry data to model the maneuver thrust process. Combining the thrust and other orbital perturbations, a long arc of 6 days’ CAPS ranging data is analyzed. If the telemetry data are not available or contain significant errors, attempts are made to estimate thrusting parameters using CAPS ranging data in the POD as an alternative to properly account for the maneuver. Two strategies achieve reasonably good data fitting level in the tested arc with the maximal position difference being about 20 m.

  14. Observability Analysis of DVL/PS Aided INS for a Maneuvering AUV

    Directory of Open Access Journals (Sweden)

    Itzik Klein

    2015-10-01

    Full Text Available Recently, ocean exploration has increased considerably through the use of autonomous underwater vehicles (AUV. A key enabling technology is the precision of the AUV navigation capability. In this paper, we focus on understanding the limitation of the AUV navigation system. That is, what are the observable error-states for different maneuvering types of the AUV? Since analyzing the performance of an underwater navigation system is highly complex, to answer the above question, current approaches use simulations. This, of course, limits the conclusions to the emulated type of vehicle used and to the simulation setup. For this reason, we take a different approach and analyze the system observability for different types of vehicle dynamics by finding the set of observable and unobservable states. To that end, we apply the observability Gramian approach, previously used only for terrestrial applications. We demonstrate our analysis for an underwater inertial navigation system aided by a Doppler velocity logger or by a pressure sensor. The result is a first prediction of the performance of an AUV standing, rotating at a position and turning at a constant speed. Our conclusions of the observable and unobservable navigation error states for different dynamics are supported by extensive numerical simulation.

  15. Observability analysis of DVL/PS aided INS for a maneuvering AUV.

    Science.gov (United States)

    Klein, Itzik; Diamant, Roee

    2015-10-22

    Recently, ocean exploration has increased considerably through the use of autonomous underwater vehicles (AUV). A key enabling technology is the precision of the AUV navigation capability. In this paper, we focus on understanding the limitation of the AUV navigation system. That is, what are the observable error-states for different maneuvering types of the AUV? Since analyzing the performance of an underwater navigation system is highly complex, to answer the above question, current approaches use simulations. This, of course, limits the conclusions to the emulated type of vehicle used and to the simulation setup. For this reason, we take a different approach and analyze the system observability for different types of vehicle dynamics by finding the set of observable and unobservable states. To that end, we apply the observability Gramian approach, previously used only for terrestrial applications. We demonstrate our analysis for an underwater inertial navigation system aided by a Doppler velocity logger or by a pressure sensor. The result is a first prediction of the performance of an AUV standing, rotating at a position and turning at a constant speed. Our conclusions of the observable and unobservable navigation error states for different dynamics are supported by extensive numerical simulation.

  16. Determination of baroreflex sensitivity during the modified Oxford maneuver by trigonometric regressive spectral analysis.

    Directory of Open Access Journals (Sweden)

    Julia Gasch

    Full Text Available BACKGROUND: Differences in spontaneous and drug-induced baroreflex sensitivity (BRS have been attributed to its different operating ranges. The current study attempted to compare BRS estimates during cardiovascular steady-state and pharmacologically stimulation using an innovative algorithm for dynamic determination of baroreflex gain. METHODOLOGY/PRINCIPAL FINDINGS: Forty-five volunteers underwent the modified Oxford maneuver in supine and 60° tilted position with blood pressure and heart rate being continuously recorded. Drug-induced BRS-estimates were calculated from data obtained by bolus injections of nitroprusside and phenylephrine. Spontaneous indices were derived from data obtained during rest (stationary and under pharmacological stimulation (non-stationary using the algorithm of trigonometric regressive spectral analysis (TRS. Spontaneous and drug-induced BRS values were significantly correlated and display directionally similar changes under different situations. Using the Bland-Altman method, systematic differences between spontaneous and drug-induced estimates were found and revealed that the discrepancy can be as large as the gain itself. Fixed bias was not evident with ordinary least products regression. The correlation and agreement between the estimates increased significantly when BRS was calculated by TRS in non-stationary mode during the drug injection period. TRS-BRS significantly increased during phenylephrine and decreased under nitroprusside. CONCLUSIONS/SIGNIFICANCE: The TRS analysis provides a reliable, non-invasive assessment of human BRS not only under static steady state conditions, but also during pharmacological perturbation of the cardiovascular system.

  17. The utility of Valsalva maneuver in the diagnoses of orthostatic disorders.

    Science.gov (United States)

    Palamarchuk, Iryna S; Baker, Jacquie; Kimpinski, Kurt

    2016-02-01

    The objective of this study was to assess hemodynamic responses and baroreflex sensitivity (BRS) indexes during Valsalva maneuver (VM) and head-up tilt (HUT) testing in orthostatic intolerance (OI). Patients with neurogenic orthostatic hypotension (NOH, n = 26), postural tachycardia syndrome (n = 26) and symptomatic OI (n = 14) were compared with healthy population (control, n = 107) and inappropriate sinus tachycardia (n = 7). Hemodynamic assessment included patterning and quantification with vagal and adrenergic BRS (BRSa/BRSa1). In NOH, cardiovagal systolic blood pressure (SBP) decrements in VM and HUT were correlated (r = 0.660, P 0.05) or was not applicable in 60% of NOH. In symptomatic OI, compared with control, cardiovagal SBP decrements were larger (P postural tachycardia syndrome ("N" pattern), but by 3 s in inappropriate sinus tachycardia ("M" pattern). Visualization of distinct VM patterns allows primary evaluation of autonomic dysfunction and differentiation of the various forms of OI. BRSa1 evaluation is compromised by pathological SBP patterns. VM patterning is a valuable nonpostural supplement to HUT capable of detecting and differentiating OI.

  18. Efficacy of recruitment maneuver for improving the brain dead marginal lungs to ideal.

    Science.gov (United States)

    Parto, S; Shafaghi, S; Khoddami-Vishteh, H-R; Makki, S Mohammad; Abbasidezfuli, A; Daneshvar, A; Sheikhy, K; Faeghi, J; Ghorbani, F; Parsa, T; Najafizadeh, K

    2013-01-01

    Because of the shortage of lungs for transplantation, finding the suitable lungs in brain-dead donors is an important issue. Recruitment maneuver is a strategy aimed at re-expanding collapsed and edematous lung tissue. The aim of this study was to assess the efficacy of this maneuver on improving marginal lungs for transplantation. From 127 brain-dead potential donor which were evaluated for lung donation in Masih Daneshvari Organ Procurement Unit of Tehran, Iran, 31 (25%) had marginal lungs for transplantation. These donors had normal chest X ray or bilateral infiltration and had PaO2 200-300 mm Hg with FIO2 100%. The recruitment maneuver was performed and arterial blood gas was obtained before and after maneuver. The maneuver lasts for 2 hours with continuous check of O2 saturation and patient's hemodynamic during. Finally, patients with normal bronchoscopy and PaO2/FIO2 >300 mm Hg were considered good candidates for lung transplantation. The frequency (%) and mean ± SD were used for description of variables and the Wilcoxon test was used for comparison between pre- and post-maneuver PaO2 with FIO2 100%. The mean ± SD of PaO2/FIO2 with 100% FIO2 of patients before and after recruitment were 239 ± 62 and 269 ± 91, respectively. Recruitment maneuver could convert 10 marginal lungs (32%) to appropriate ones (PaO2 > 300) and finally 8 lungs were transplanted. Findings of this study showed that recruitment maneuver could convert inappropriate lungs to appropriate ones in one third of brain-dead patients who had marginal lung condition. So, it is recommended that this maneuver is considered in the assessment protocol of lungs for donation. Copyright © 2013 Elsevier Inc. All rights reserved.

  19. 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...... the propensity to perform crash avoidance maneuvers, and (5) visual obstruction and artificial illumination decrease the probability to carry out crash avoidance maneuvers. Conclusions: The results emphasize the need for public awareness campaigns to promote safe driving style for senior drivers and warning...

  20. [Treatment of the benign paroxysmal positional vertigo (BPPV) by Epley maneuver].

    Science.gov (United States)

    Pino Rivero, V; Pantoja Hernández, C G; González Palomino, A; Mora Santos, M E; Marcos García, M; Montero García, C; Blasco Huelva, A

    2007-01-01

    Benign paroxysmal positional vertigo (BPPV) is the most common of the peripheral vertigo. We report the case of a 45 years old female with that pathology suspected by the symptoms which the patient related to head changes of positions and movements. Her diagnosis was confirmed by the maneuver of Dix-Hallpike, that was positive, and the treatment consisted in a maneuver of canalicular reposition according to Epley's technique. Such maneuver was successful and actually the patient is without symptoms after more than 2 years since the first episode. Finally we have performed a bibliographic review to verify the effectiveness of that treatment.

  1. Proximal aortic stent-graft displacement with type I endoleak due to Heimlich maneuver.

    Science.gov (United States)

    Lin, Peter H; Bush, Ruth L; Lumsden, Alan B

    2003-08-01

    The Heimlich maneuver has saved countless lives by relieving foreign body obstruction from the respiratory tract. Complications related to this life-saving technique, particularly involving the abdominal aorta, are extremely rare. We report the case of a patient who underwent successful endovascular abdominal aortic aneurysm (AAA) repair, with AAA reduction at postoperative surveillance. Endograft displacement after performance of the Heimlich maneuver resulted in a proximal type I endoleak. This case underscores both the potential for aortic trauma from the Heimlich maneuver and the risk for clinical failure as a result of abdominal compression after successful endovascular AAA repair.

  2. Development and flight test of an experimental maneuver autopilot for a highly maneuverable aircraft

    Science.gov (United States)

    Duke, Eugene L.; Jones, Frank P.; Roncoli, Ralph B.

    1986-01-01

    This report presents the development of an experimental flight test maneuver autopilot (FTMAP) for a highly maneuverable aircraft. The essence of this technique is the application of an autopilot to provide precise control during required flight test maneuvers. This newly developed flight test technique is being applied at the Dryden Flight Research Facility of NASA Ames Research Center. The FTMAP is designed to increase the quantity and quality of data obtained in test flight. The technique was developed and demonstrated on the highly maneuverable aircraft technology (HiMAT) vehicle. This report describes the HiMAT vehicle systems, maneuver requirements, FTMAP development process, and flight results.

  3. Development of a flight test maneuver autopilot for a highly maneuverable aircraft

    Science.gov (United States)

    Duke, E. L.; Jones, F. P.; Roncoli, R. B.

    1983-01-01

    This paper details the development of a flight test maneuver autopilot for a highly maneuverable aircraft. This newly developed flight test technique is being applied at the Dryden Flight Research Facility of the NASA Ames Research Center. The flight test maneuver autopilot (FTMAP) is designed to increase the quantity and quality of the data obtained in flight test. The vehicle with which it is being used is the highly maneuverable aircraft technology (HiMAT) vehicle. This paper describes the HiMAT vehicle systems, maneuver requirements, FTMAP development process, and flight results.

  4. Intensive Abdominal Drawing-In Maneuver After Unipedal Postural Stability in Nonathletes With Core Instability

    Science.gov (United States)

    Lee, Nam G.; You, Joshua (Sung) H.; Kim, Tae H.; Choi, Bong S.

    2015-01-01

    Context: The exact neuromechanical nature and relative contribution of the abdominal drawing-in maneuver (ADIM) to postural instability warrants further investigation in uninjured and injured populations. Objective: To determine the effects of the ADIM on static core and unipedal postural stability in nonathletes with core instability. Design: Controlled laboratory study. Setting: University research laboratory. Patients or Other Participants: A total of 19 nonathletes (4 women: age = 22.3 ± 1.3 years, height = 164.0 ± 1.7 cm, mass = 56.0 ± 4.6 kg; 15 men: age = 24.6 ± 2.8 years, height = 172.6 ± 4.7 cm, mass = 66.8 ± 7.6 kg) with core instability. Intervention(s): Participants received ADIM training with visual feedback 20 minutes each day for 7 days each week over a 2-week period. Main Outcome Measures(s): Core instability was determined using a prone formal test and measured by a pressure biofeedback unit. Unipedal postural stability was determined by measuring the center-of-pressure sway and associated changes in the abdominal muscle-thickness ratios. Electromyographic activity was measured concurrently in the external oblique, erector spinae, gluteus medius, vastus medialis oblique, tibialis anterior, and medial gastrocnemius muscles. Results: All participants initially were unable to complete the formal test. However, after the 2-week ADIM training period, all participants were able to reduce the pressure biofeedback unit by a range of 4 to 10 mm Hg from an initial 70 mm Hg and maintain it at 60 to 66 mm Hg with minimal activation of the external oblique (t18 = 3.691, P = .002) and erector spinae (t18 = 2.823, P = .01) muscles. Monitoring of the pressure biofeedback unit and other muscle activations confirmed that the correct muscle contraction defining the ADIM was accomplished. This core stabilization was well maintained in the unipedal-stance position, as evidenced by a decrease in the center-of-pressure sway measures (t18 range, 3.953–5.775, P

  5. Unipedal postural stability in nonathletes with core instability after intensive abdominal drawing-in maneuver.

    Science.gov (United States)

    Lee, Nam G; You, Joshua Sung H; Kim, Tae H; Choi, Bong S

    2015-02-01

    The exact neuromechanical nature and relative contribution of the abdominal drawing-in maneuver (ADIM) to postural instability warrants further investigation in uninjured and injured populations. To determine the effects of the ADIM on static core and unipedal postural stability in nonathletes with core instability. Controlled laboratory study. University research laboratory. A total of 19 nonathletes (4 women: age = 22.3 ± 1.3 years, height = 164.0 ± 1.7 cm, mass = 56.0 ± 4.6 kg; 15 men: age = 24.6 ± 2.8 years, height = 172.6 ± 4.7 cm, mass = 66.8 ± 7.6 kg) with core instability. Participants received ADIM training with visual feedback 20 minutes each day for 7 days each week over a 2-week period. Core instability was determined using a prone formal test and measured by a pressure biofeedback unit. Unipedal postural stability was determined by measuring the center-of-pressure sway and associated changes in the abdominal muscle-thickness ratios. Electromyographic activity was measured concurrently in the external oblique, erector spinae, gluteus medius, vastus medialis oblique, tibialis anterior, and medial gastrocnemius muscles. All participants initially were unable to complete the formal test. However, after the 2-week ADIM training period, all participants were able to reduce the pressure biofeedback unit by a range of 4 to 10 mm Hg from an initial 70 mm Hg and maintain it at 60 to 66 mm Hg with minimal activation of the external oblique (t(18) = 3.691, P = .002) and erector spinae (t(18) = 2.823, P = .01) muscles. Monitoring of the pressure biofeedback unit and other muscle activations confirmed that the correct muscle contraction defining the ADIM was accomplished. This core stabilization was well maintained in the unipedal-stance position, as evidenced by a decrease in the center-of-pressure sway measures (t(18) range, 3.953-5.775, P core and postural stability in nonathletes with core instability.

  6. An advanced regulator for the helium pressurization systems of the Space Shuttle OMS and RCS

    Science.gov (United States)

    Wichmann, H.

    1973-01-01

    The Space Shuttle Orbit Maneuvering System and Reaction Control System are pressure-fed rocket propulsion systems utilizing earth storable hypergolic propellants and featuring engines of 6000 lbs and 900 lbs thrust, respectively. The helium pressurization system requirements for these propulsion systems are defined and the current baseline pressurization systems are described. An advanced helium pressure regulator capable of meeting both OMS and RCS helium pressurization system requirements is presented and its operating characteristics and predicted performance characteristics are discussed.

  7. Computation of Hypersonic Flow about Maneuvering Vehicles with Changing Shapes

    Energy Technology Data Exchange (ETDEWEB)

    Ferencz, R M; Felker, F F; Castillo, V M

    2004-02-23

    Vehicles moving at hypersonic speeds have great importance to the National Security. Ballistic missile re-entry vehicles (RV's) travel at hypersonic speeds, as do missile defense intercept vehicles. Despite the importance of the problem, no computational analysis method is available to predict the aerodynamic environment of maneuvering hypersonic vehicles, and no analysis is available to predict the transient effects of their shape changes. The present state-of-the-art for hypersonic flow calculations typically still considers steady flow about fixed shapes. Additionally, with present computational methods, it is not possible to compute the entire transient structural and thermal loads for a re-entry vehicle. The objective of this research is to provide the required theoretical development and a computational analysis tool for calculating the hypersonic flow about maneuvering, deforming RV's. This key enabling technology will allow the development of a complete multi-mechanics simulation of the entire RV flight sequence, including important transient effects such as complex flight dynamics. This will allow the computation of the as-delivered state of the payload in both normal and unusual operational environments. This new analysis capability could also provide the ability to predict the nonlinear, transient behavior of endo-atmospheric missile interceptor vehicles to the input of advanced control systems. Due to the computational intensity of fluid dynamics for hypersonics, the usual approach for calculating the flow about a vehicle that is changing shape is to complete a series of steady calculations, each with a fixed shape. However, this quasi-steady approach is not adequate to resolve the frequencies characteristic of a vehicle's structural dynamics. Our approach is to include the effects of the unsteady body shape changes in the finite-volume method by allowing for arbitrary translation and deformation of the control volumes. Furthermore

  8. Pulmonary oligemia maneuver can alleviate pulmonary artery injury during pulmonary thromboendarterectomy procedure

    Institute of Scientific and Technical Information of China (English)

    GAN Hui-li; ZHANG Jian-qun; LU Jia-kai; DONG Xiu-hua; HOU Xiao-tong; GAO Yuan-ming; ZHU Guang-fa

    2013-01-01

    Background Pulmonary thromboendarterectomy (PTE) has evolved as a treatment of choice for chronic thromboembolic pulmonary hypertension (CTEPH).This study aimed to characterize if pulmonary oligemia maneuver (POM) can alleviate pulmonary artery injury during PTE procedure.Methods A total of 112 cases of CTEPH admitted to Beijing Anzhen Hospital from March 2002 to August 2011 received PTE procedure.They were retrospectively classified as non-POM group (group A,n=55) or POM group (group B,n=57).Members from group B received POM during rewarming period,whereas members from group A did not.Results There were three (5.45%) early deaths in group A,no death in group B (0) (Fisher's exact test,P=-0.118).Six patients in group A needed extracorporeal membrane oxygenation (ECMO) as life support after the PTE procedure,no patients in group B needed ECMO (Fisher's exact test,P=0.013).The patients in group B had a shorter intubation and ICU stay,lower mean pulmonary arterial pressure (mPAP) and pulmonary vascular resistance (PVR),higher partial pressure of oxygen in artery (PaO2) and arterial oxygen saturation (SaO2) and less medical expenditure than patients in group A.With a mean follow-up time of (58.3 ± 30.6) months,two patients in group A and one patient in group B died.The difference of the actuarial survival after the procedure between the two groups did not reach statistical significance.Three months post the PTE procedure,the difference of residual occluded pulmonary segment between the two groups did not reach statistical significance (P=-0.393).Conclusion POM can alleviate pulmonary artery injury,shorten ICU stay and intubation time,and lower down the rate of ECMO after PTE procedure.

  9. Symphysis-fundal height curve in the diagnosis of fetal growth deviations Curva de altura uterina por edad de gestación y diagnóstico de desvíos del crecimiento fetal Curva de altura uterina por idade gestacional e diagnóstico de desvios do crescimento fetal

    Directory of Open Access Journals (Sweden)

    Djacyr Magna Cabral Freire

    2010-12-01

    Full Text Available OBJECTIVE: To validate a new symphysis-fundal curve for screening fetal growth deviations and to compare its performance with the standard curve adopted by the Brazilian Ministry of Health. METHODS: Observational study including a total of 753 low-risk pregnant women with gestational age above 27 weeks between March to October 2006 in the city of João Pessoa, Northeastern Brazil. Symphisys-fundal was measured using a standard technique recommended by the Brazilian Ministry of Health. Estimated fetal weight assessed through ultrasound using the Brazilian fetal weight chart for gestational age was the gold standard. A subsample of 122 women with neonatal weight measurements was taken up to seven days after estimated fetal weight measurements and symphisys-fundal classification was compared with Lubchenco growth reference curve as gold standard. Sensitivity, specificity, positive and negative predictive values were calculated. The McNemar χ2 test was used for comparing sensitivity of both symphisys-fundal curves studied. RESULTS: The sensitivity of the new curve for detecting small for gestational age fetuses was 51.6% while that of the Brazilian Ministry of Health reference curve was significantly lower (12.5%. In the subsample using neonatal weight as gold standard, the sensitivity of the new reference curve was 85.7% while that of the Brazilian Ministry of Health was 42.9% for detecting small for gestational age. CONCLUSIONS: The diagnostic performance of the new curve for detecting small for gestational age fetuses was significantly higher than that of the Brazilian Ministry of Health reference curve.OBJETIVO: Validar la curva de referencia de altura uterina por edad de gestación para el rastreo de desvíos del crecimiento fetal y comparar su performance con la curva estándar adoptada por el Ministerio de la Salud de Brasil. MÉTODOS: Estudio observacional que envolvió 753 gestantes de bajo riesgo de Joao Pessoa, Noreste de Brasil, entre

  10. Heading Lock Maneuver Testing of Autonomous Underwater Vehicle

    CERN Document Server

    Muljowidodo, K

    2008-01-01

    In recent years, Autonomous Underwater Vehicle (UAV) research and development at Bandung Institute of Technology in Indonesia has achieved the testing stage in the field. This testing was still being classified as the early testing, since some of the preliminary tests were carried out in the scale of the laboratory. The paper would discuss the laboratory test and several tests that were done in the field. Discussions were stressed in the procedure and the aim that will be achieved, along with several early results. The testing was carried out in the lake with the area around 8300 Ha and the maximum depth of 50 meters. The location of the testing was chosen with consideration of minimizing the effect of the current and the wave, as well as the location that was not too far from the Laboratory. The type of testing that will be discussed in paper was Heading Lock Maneuver Testing. The vehicle was tested to move with a certain cruising speed, afterwards it was commanded by an arbitrarily selected heading directio...

  11. 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.

  12. 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.

  13. The potential role of epigenetic modulations in BPPV maneuver exercises.

    Science.gov (United States)

    Tsai, Kun-Ling; Wang, Chia-To; Kuo, Chia-Hua; Cheng, Yuan-Yang; Ma, Hsin-I; Hung, Ching-Hsia; Tsai, Yi-Ju; Kao, Chung-Lan

    2016-06-14

    Benign paroxysmal positional vertigo (BPPV) is one of the most common complaints encountered in clinics and is strongly correlated with advanced age or, possibly, degeneration. Redistribution exercises are the most effective approaches to treat BPPV, and canalith repositioning procedure (CRP) cure most BPPV cases. However, the mechanisms through which the treatment modulates systemic molecules in BPPV patients remain largely unknown. In this study, we report that the miR-34a and Sirtuin 1 (SIRT1) genes correlated with the treatment effects of CRP in BPPV subjects. We found that miR-34a expression was largely inhibited and SIRT1 expression was significantly reversed after BPPV maneuver treatment. We also confirmed that the PPAR-γ, PGC-1 and FoxO gene expressions were decreased immediately after canalith repositioning procedure (CRP) for BPPV, and were largely increased after a complete cure of BPPV. Moreover, we observed that after a complete recovery of BPPV, the ROS concentrations, pro-inflammatory cytokine concentrations and p53 expression levels were attenuated. We conclude that BPPV treatment might involve some epigenetic regulations through the mediation of miR-34a, SIRT1 functions and repression of redox status.

  14. Atmospheric environment during maneuvering descent from Martian orbit

    Science.gov (United States)

    Tauber, Michael E.; Bowles, Jeffrey V.; Yang, Lily

    1989-01-01

    This paper presents an analysis of the atmospheric maneuvering capability of a vehicle designated to land on the Martian surface, together with an analysis of the entry environment encountered by the vehicle. A maximum lift/drag ratio of 2.3 was used for all trajectory calculations. The maximum achievable lateral ranges varied from about 3400 km to 2500 km for entry velocities of 5 km/s (from a highly elliptical Martian orbit) and 3.5 km/s (from a low-altitude lower-speed orbit), respectively. It is shown that the peak decelerations are an order of magnitude higher for the 5-km/s entries than for the 3.5-km/s entries. The vehicle entering at 3.5 km/s along a gliding trajectory encountered a much more benign atmospheric environment. In addition, the glider's peak deceleration was found to be only about 0.7 earth g, making the shallow flight path ideal for manned vehicles whose crews might be physically weakened by the long voyage to Mars.

  15. Evaluation and analysis of the orbital maneuvering vehicle video system

    Science.gov (United States)

    Moorhead, Robert J., II

    1989-12-01

    The work accomplished in the summer of 1989 in association with the NASA/ASEE Summer Faculty Research Fellowship Program at Marshall Space Flight Center is summarized. The task involved study of the Orbital Maneuvering Vehicle (OMV) Video Compression Scheme. This included such activities as reviewing the expected scenes to be compressed by the flight vehicle, learning the error characteristics of the communication channel, monitoring the CLASS tests, and assisting in development of test procedures and interface hardware for the bit error rate lab being developed at MSFC to test the VCU/VRU. Numerous comments and suggestions were made during the course of the fellowship period regarding the design and testing of the OMV Video System. Unfortunately from a technical point of view, the program appears at this point in time to be trouble from an expense prospective and is in fact in danger of being scaled back, if not cancelled altogether. This makes technical improvements prohibitive and cost-reduction measures necessary. Fortunately some cost-reduction possibilities and some significant technical improvements that should cost very little were identified.

  16. The potential role of epigenetic modulations in BPPV maneuver exercises

    Science.gov (United States)

    Tsai, Kun-Ling; Wang, Chia-To; Kuo, Chia-Hua; Cheng, Yuan-Yang; Ma, Hsin-I; Hung, Ching-Hsia; Tsai, Yi-Ju; Kao, Chung-Lan

    2016-01-01

    Benign paroxysmal positional vertigo (BPPV) is one of the most common complaints encountered in clinics and is strongly correlated with advanced age or, possibly, degeneration. Redistribution exercises are the most effective approaches to treat BPPV, and canalith repositioning procedure (CRP) cure most BPPV cases. However, the mechanisms through which the treatment modulates systemic molecules in BPPV patients remain largely unknown. In this study, we report that the miR-34a and Sirtuin 1 (SIRT1) genes correlated with the treatment effects of CRP in BPPV subjects. We found that miR-34a expression was largely inhibited and SIRT1 expression was significantly reversed after BPPV maneuver treatment. We also confirmed that the PPAR-γ, PGC-1 and FoxO gene expressions were decreased immediately after canalith repositioning procedure (CRP) for BPPV, and were largely increased after a complete cure of BPPV. Moreover, we observed that after a complete recovery of BPPV, the ROS concentrations, pro-inflammatory cytokine concentrations and p53 expression levels were attenuated. We conclude that BPPV treatment might involve some epigenetic regulations through the mediation of miR-34a, SIRT1 functions and repression of redox status. PMID:27203679

  17. 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.

  18. Observability analysis of DVL/PS aided INS for a maneuvering AUV

    National Research Council Canada - National Science Library

    Klein, Itzik; Diamant, Roee

    2015-01-01

    .... That is, what are the observable error-states for different maneuvering types of the AUV? Since analyzing the performance of an underwater navigation system is highly complex, to answer the above question, current approaches use simulations...

  19. Hybrid Switching Controller Design for the Maneuvering and Transit of a Training Ship

    National Research Council Canada - National Science Library

    Mirosław Tomera

    2017-01-01

    .... This task requires integrating several operating modes, such as maneuvering the ship at low speeds, steering the ship at different speeds in the course or along the trajectory, and stopping the ship on the route...

  20. Maneuvering of flexible spacecraft with application to SCOLE. [Spacecraft Control Laboratory Experiment

    Science.gov (United States)

    Meirovitch, L.; Quinn, R. D.; Norris, M. A.

    1985-01-01

    This paper is concerned with the derivation of the equations of motion for the Spacecraft Control Laboratory Experiment (SCOLE). For future reference, the equations of motion of a similar structure orbiting the earth are also derived. The structure is assumed to undergo large rigid-body maneuvers and small elastic deformations. A perturbation approach is presented where the quantities defining the rigid-body maneuver are assumed to be relatively large, with the elastic deformations and deviations from the rigid-body maneuver being relatively small. The perturbation equations have the form of linear, non-self-adjoint equations with time-dependent coefficients. An active control technique can then be formulated to permit maneuvering of the spacecraft and simultaneously suppressing the elastic vibration.

  1. 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.

  2. Efficacy of Epley's Maneuver in Treating BPPV Patients: A Prospective Observational Study

    Science.gov (United States)

    Gaur, Sushil; Awasthi, Sanjeev Kumar; Bhadouriya, Sunil Kumar Singh; Saxena, Rohit; Pathak, Vivek Kumar; Bisht, Mamta

    2015-01-01

    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. PMID:26495002

  3. Real-Time, Maneuvering Flight Noise Prediction for Rotorcraft Flight Simulations Project

    Data.gov (United States)

    National Aeronautics and Space Administration — This proposal outlines a plan for developing new technology to provide accurate real-time noise prediction for rotorcraft in steady and maneuvering flight. Main...

  4. Fundamental Study of Evaluation at Berthing Training for Pilot Trainees Using a Ship Maneuvering Simulator

    National Research Council Canada - National Science Library

    Kazuki Inoue; Tadatsugi Okazaki; Koji Murai; Yuji Hayashi

    2013-01-01

    Use of the ship maneuvering simulator (SMS) is at the core of pilot trainees education and training, so it is desirable to have an evaluation method that can be completed shortly after each berthing training session...

  5. Fatal splenic rupture following Heimlich maneuver: case report and literature review.

    Science.gov (United States)

    Cecchetto, Giovanni; Viel, Guido; Cecchetto, Attilio; Kusstatscher, Stefano; Montisci, Massimo

    2011-06-01

    The most effective resuscitative procedure in choking by foreign bodies is the Heimlich maneuver, described for the first time by Henry Heimlich (1974) and recognized by the US Surgeon General (1985) as the "only method that should be used for the treatment of choking from foreign body airway obstruction." If performed correctly, this lifesaving maneuver is associated with rare complications, of which the most frequent are rib fractures and gastric or esophagus perforations. Other rare traumatic injuries such as pneumomediastinum, aortic valve cusp rupture, diaphragmatic herniation, jejunum perforation, hepatic rupture, or mesenteric laceration have been described.However, we are unaware of previous reports of splenic rupture after Heimlich maneuver. We present an interesting case of fatal hemoperitoneum due to a hilar laceration of the spleen following a correctly performed Heimlich maneuver.

  6. Method to maintain artificial gravity during transfer maneuvers for tethered spacecraft

    Science.gov (United States)

    Martin, Kaela M.; Landau, Damon F.; Longuski, James M.

    2016-03-01

    Artificial gravity has long been proposed to limit the harmful effects of the micro-gravity environment on human crews during mission to Mars. A tethered spacecraft spinning at 4 rpm (to avoid motion sickness) provides an attractive configuration. However, if the spacecraft is required to spin down for impulsive maneuvers and then spin up for interplanetary travel, the propellant cost may be unacceptably high. This paper proposes a maneuver that is performed while the spacecraft is spinning thus avoiding additional spin-down and spin-up maneuvers. A control law is provided to achieve the required ΔV while maintaining spin rate. A hypothetical human mission from Earth to Mars is analyzed using the new maneuver which, in this example, may save over 700 kg of propellant.

  7. Comparison of various schema of filter adaptivity for the tracking of maneuvering targets

    Science.gov (United States)

    Jouan, Alexandre; Bosse, Eloi; Simard, Marc-Alain; Shahbazian, Elisa

    1998-09-01

    Tracking maneuvering targets is a complex problem which has generated a great deal of effort over the past several years. It has now been well established that in terms of tracking accuracy, the Interacting Multiple Model (IMM) algorithm, where state estimates are mixed, performs significantly better for maneuvering targets than other types of filters. However, the complexity of the IMM algorithm can prohibit its use in these applications of which similar algorithms cannot provide the necessary accuracy and which can ont afford the computational load of IMM algorithm. This paper presents the evaluation of the tracking accuracy of a multiple model track filter using three different constant-velocity models running in parallel and a maneuver detector. The output estimate is defined by selecting the model whose likelihood function is lower than a target maneuver threshold.

  8. Effects of bronchomotor tone and gas density on time dependence of forced expiratory vital capacity maneuver.

    Science.gov (United States)

    D'Angelo, E; Milic-Emili, J; Marazzini, L

    1996-11-01

    It has been shown that in normal subjects and chronic obstructive pulmonary disease (COPD) patients the maximal expiratory flows and FEV1 are significantly higher if the FVC maneuver is preceded by a rapid inspiration without an end-inspiratory pause (maneuver 1) compared with a slow inspiration with an end-inspiratory pause of approximately 5 s (maneuver 2). This time dependency of FVC was attributed primarily to loss of lung recoil (stress relaxation) during breath-holding at TLC, in association with time constant inequality within the lungs, and changes in bronchomotor tone. To examine the role of bronchomotor tone on time dependency of FVC, 11 COPD and 10 asthmatic patients performed FVC maneuvers 1 and 2 before and after administration of a bronchodilator drug (salbutamol). In addition, using the same approach, the effects of changing airway resistance per se were assessed in another group of 10 COPD patients and 10 normal subjects, while breathing air and after equilibration with 80% helium in oxygen. Main findings were: peak expiratory flow (PEF), FEV1, and maximal midexpiratory flow rate (MMF) were significantly larger with maneuver 1 than 2; after salbutamol administration and during helium-oxygen breathing, all indices increased significantly with both maneuvers but the relative differences between maneuvers 1 and 2 were unchanged. We conclude that time dependency of maximal expiratory flow-volume (MEFV) curves, as indexed by PEF, FEV1, and MMF, is largely independent of bronchomotor tone and gas density, and probably reflects mainly stress relaxation of the respiratory tissues. The relevance of time dependency of FVC maneuver in the assessment of bronchodilator response and density dependence is discussed.

  9. Energy-balanced multiple-sensor collaborative scheduling for maneuvering target tracking in wireless sensor networks

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    An energy-balanced multiple-sensor collaborative scheduling is proposed for maneuvering target tracking in wireless sensor networks (WSNs). According to the position of the maneuvering target, some sensor nodes in WSNs are awakened to form a sensor cluster for target tracking collaboratively. In the cluster, the cluster head node is selected to implement tracking task with changed sampling interval. The distributed interactive multiple model (IMM) filter is employed to estimate the target state. The estimat...

  10. The prospect of responsive spacecraft using aeroassisted, trans-atmospheric maneuvers

    Science.gov (United States)

    Bettinger, Robert A.

    Comprised of exo- and trans-atmospheric trajectory segments, atmospheric re-entry represents a complex dynamical event which traditionally signals the mission end-of-life for low-Earth orbit (LEO) spacecraft, both manned and unmanned. Transcending this paradigm, atmospheric re-entry can be employed as a means of operational maneuver whereby the aerodynamic forces of the upper atmosphere can be exploited to create an aeroassisted maneuver. Utilizing a notional trans-atmospheric, lifting re-entry vehicle with L/D=6, the first phase of research demonstrates the terrestrial reachability potential for skip entry aeroassisted maneuvers. By overflying a geographically diverse set of sample ground targets, comparative analysis indicates a significant savings in DeltaV expenditure for skip entry compared with planar phasing and simple plane change exo-atmospheric maneuvers. In the second phase, the Design of Experiments method of orthogonal arrays provides optimal vehicle and skip entry trajectory designs by employing main effects and Pareto front analysis. Depending on the chosen re-circularization altitude, the coupled optimal design can achieve an inclination change of 19.91 deg with 50-85% less DeltaV than a simple plane change. Finally, the third phase introduces the descent-boost aeroassisted maneuver as an alternative to combined Hohmann and bi-elliptic transfers in order to perform LEO injection. Compared with bi-elliptic transfers, simulations demonstrate that a lifting re-entry vehicle with L/D=6 performing a descent-boost maneuver requires 6-12% less DeltaV for injection into orbits lower than 650 km. In addition, the third phase also introduces the "Maneuver Performance Number" as a dimensionless means of comparative effectiveness analysis for both exo- and trans-atmospheric maneuvers.

  11. Braking News: the Link between Crash Severity and Crash Avoidance Maneuvers

    DEFF Research Database (Denmark)

    Kaplan, Sigal; Prato, Carlo Giacomo

    2012-01-01

    avoidance maneuvers and crash severity, with differences emerging for different critical events. Moreover, results show two trends: (i) most drivers fail to act when facing critical events, and (ii) drivers rarely perform crash avoidance maneuvers that are correlated with higher probability of lower crash...... severity. These trends suggest that effort should be posed toward understanding the reaction mechanisms to different critical events, improving in-vehicle warning systems, promoting responsible driving behavior, and designing forgiving infrastructures....

  12. Efficacy of Epley maneuver in treatment of benign paroxysmal positional vertigo of the posterior semicircular canal

    Directory of Open Access Journals (Sweden)

    Babac Snežana

    2012-01-01

    Full Text Available Background/Aim. Benign paroxysmal positional vertigo is one of the most frequent peripheral vestibular system disorders. The aim of this study was to examine the efficacy of the Epley maneuver in treating benign paroxysmal positional vertigo of the posterior semicircular canal (p- BPPV and to discover possible causes of failure. Methods. This prospective study included 75 patients. In all the cases medical history showed and the positioning Dix-Hallpike test confirmed the diagnosis of p-BPPV. We also performed clinical ENT examination, searching for spontaneous nystagmus, vestibulospinal tests, caloric test, and audiometry. All the patients were treated by the modified Epley canalith repositioning maneuver. The patients were followed up at the intervals of seven and, fourteen days, and one, tree, and six months and one year. The maneuver was repeated if vertigo and nystagmus on control positioning test persisted. The transition from positive into negative Dix Hallpike test after one or two Epley maneuver was considered as success in treatment. Results. After the initial Epley maneuver the recovery rate was 90.7%, and after the second 96%. In three (4% patients with secondary p-BPPV, symptoms did not cease even after the second repositioning maneuver. The etiology of p-BPPV had a significant effect on the maneuver’s success rate (p < 0.01, whereas duration of symptoms, age and gender had no effect (p > 0.05. After a successful treatment 11 (14.66% patients had recurrent attack of BPPV during the first year. Conclusion. The Epley maneuver is very successful repositioning procedure in treating p- BPPV. The patients with idiopathic form p-BPPV showed higher success rate with Epley maneuver than those with secondary p-BPPV.

  13. Proportional Plus Integral Control of Aircraft for Automated Maneuvering Formation Flight

    Science.gov (United States)

    1991-12-01

    3-11 3.6 Formation Kinematic Equations Development 3-12 3.7 Aircraft Longitudinal (X) Channel Maneuvering 3-17 3.8 Aircraft Lateral (Y...response of the respective aircraft . Longitudinal position along the flight path vector is a direct function of forward velocity. Velocity is determined by...equation is not needed. 3-16 3.7 Aircraft Longitudinal (X) Channel Maneuvering The longitudinal channel involves the longitudinal separation distance

  14. Traumatic rupture of Ionescu-Shiley aortic valve after the Heimlich maneuver.

    Science.gov (United States)

    Passik, C S; Ackermann, D M; Piehler, J M; Edwards, W D

    1987-05-01

    A 74-year-old woman who had undergone aortic valve replacement with an Ionescu-Shiley bioprosthesis was evaluated and treated because aortic insufficiency developed after the application of the Heimlich maneuver. Pathologic examination of the explanted valve disclosed a cuspid perforation and an adjacent tear of a second cusp at its insertion into the valve strut. Patients with unexplained acute prosthetic insufficiency should be questioned as to whether the Heimlich maneuver has been previously performed.

  15. [The influence of airway supporting maneuvers on glottis view in pediatric fiberoptic bronchoscopy].

    Science.gov (United States)

    Umutoglu, Tarik; Gedik, Ahmet Hakan; Bakan, Mefkur; Topuz, Ufuk; Daskaya, Hayrettin; Ozturk, Erdogan; Cakir, Erkan; Salihoglu, Ziya

    2015-01-01

    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. 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. 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 (p0.05). 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 (p0.05). All airway supporting maneuvers improved glottic view during pediatric flexible fiberoptic bronchoscopy; however head tilt chin lift and triple airway maneuvers were found to be the most effective maneuvers. Copyright © 2015 Sociedade Brasileira de Anestesiologia. Publicado por Elsevier Editora Ltda. All rights reserved.

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

    Science.gov (United States)

    Umutoglu, Tarik; Gedik, Ahmet Hakan; Bakan, Mefkur; Topuz, Ufuk; Daskaya, Hayrettin; Ozturk, Erdogan; Cakir, Erkan; Salihoglu, Ziya

    2015-01-01

    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. 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. 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 (p0.05). 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 (p0.05). All airway supporting maneuvers improved glottic view during pediatric flexible fiberoptic bronchoscopy; however head tilt chin lift and triple airway maneuvers were found to be the most effective maneuvers. Copyright © 2015 Sociedade Brasileira de Anestesiologia. Published by Elsevier Editora Ltda. All rights reserved.

  17. Effectiveness of Chin-tuck Maneuver to Facilitate Swallowing in Neurologic Dysphagia

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    Saconato, Mariana

    2015-10-01

    Full Text Available Introduction The chin-tuck maneuver is the most frequently employed postural maneuver in the treatment of neurogenic oropharyngeal dysphagia caused by encephalic vascular strokes and degenerative diseases. Objective The purpose of this study was to investigate the effectiveness of this maneuver in patients with neurogenic dysphagia and factors that could interfere in it. Methods In this retrospective cohort, we analyzed the medical files and videofluoroscopy exams of 35 patients (19 male – 54% and 16 female – 46%; age range between 20 and 89 years old; mean = 69 years. Results The results suggest that the effectiveness of chin-tuck maneuver is related to the overall degree of dysphagia: the more severe the dysphagia, the less effective the maneuver. Conclusion Chin-tuck maneuver should benefit dysphagic patients with delay in the swallowing trigger, reduced laryngeal elevation, and difficulties to swallow liquids, but is not the best compensatory strategy for patients with severe dysphagia.

  18. Epley's Maneuver in Benign Paroxysmal Positional Vertigo: Series of Cases Reports

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    Marchiori, Luciana Lozza de Moraes

    2011-04-01

    Full Text Available Introduction: Benign paroxysmal positional vertigo (BPPV is probably the most common cause of vertigo in women. Objective: To report the result of Epley's maneuver when treating BPPV patients. Method: Study of a series of 9-month-long cases of five female individuals aged between 46 and 64 with BPPV, who were submitted to Epley's maneuver at a scholar clinics, having the positive Dix-Hallpike maneuver at the first consultation as an inclusion criterion, and evaluations were repeated in a six and nine-month term. Results: Only one Epley's maneuver, as the only therapeutic procedure, was enough to eliminate nystagmus and positional vertigo in 4 patients, who did not show a positive Dix-Hallpike maneuver in the two reevaluations performed. Only one patient showed BPPV in the first reevaluation of the study term, and nystagmus reoccurred in the second evaluation only. Conclusion: Epley's repositioning maneuver proved to be a simple and effective BPPV treatment method for this study's patients at length.

  19. Effect of width and boundary conditions on meeting maneuvers on two-way separated cycle tracks.

    Science.gov (United States)

    Garcia, Alfredo; Gomez, Fernando Agustin; Llorca, Carlos; Angel-Domenech, Antonio

    2015-05-01

    Cycle track design guidelines are rarely based on scientific studies. In the case of off-road two-way cycle tracks, a minimum width must facilitate both passing and meeting maneuvers, being meeting maneuvers the most frequent. This study developed a methodology to observe meeting maneuvers using an instrumented bicycle, equipped with video cameras, a GPS tracker, laser rangefinders and speed sensors. This bicycle collected data on six two-way cycle tracks ranging 1.3-2.15m width delimitated by different boundary conditions. The meeting maneuvers between the instrumented bicycle and every oncoming bicycle were characterized by the meeting clearance between the two bicycles, the speed of opposing bicycle and the reaction of the opposing rider: change in trajectory, stop pedaling or braking. The results showed that meeting clearance increased with the cycle track width and decreased if the cycle track had lateral obstacles, especially if they were higher than the bicycle handlebar. The speed of opposing bicycle shown the same tendency, although were more disperse. Opposing cyclists performed more reaction maneuvers on narrower cycle tracks and on cycle tracks with lateral obstacles to the handlebar height. Conclusions suggested avoiding cycle tracks narrower than 1.6m, as they present lower meeting clearances, lower bicycle speeds and frequent reaction maneuvers.

  20. 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

  1. Orbiter Repair Maneuver Contingency Separation Methods and Analysis

    Science.gov (United States)

    Machula, Michael

    2005-01-01

    Repairing damaged thermal protection system tile requires the Space Shuttle to be oriented such that repair platform access from the International Space Station (ISS) is possible. To do this, the Space Shuttle uses the Orbiter Repair Maneuver (ORM), which utilizes the Shuttle Remote Manipulator System (SRMS) to rotate the Space Shuttle in relation to the ISS, for extended periods of time. These positions cause difficulties and challenges to performing a safe separation (no collision or thruster plume damage to sensitive ISS structures) should an inadvertent release occur or a contingency procedure require it. To help protect for an SRMS failure or other failures, a method for separating without collision and the ability to redock to ISS from the ORM configuration was needed. The contingency ORM separation solution elegantly takes advantage of orbital mechanics between ISS and the separating Space Shuttle. By pitching the ISS down approximately 45 degrees, in a majority of the ORM repair positions, the altitude difference between the ISS and Space Shuttle center of gravity is maximized. This altitude difference results in different orbital energies (orbital periods) causing objects to separate from each other without requiring translational firings. Using this method, a safe contingency ORM separation is made possible in many odd positions even though some separation positions point high powered thrusters directly at fragile ISS and Soyuz solar arrays. Documented in this paper are the development simulations and procedures of the contingency ORM separation and the challenges encountered with large constraints to work around. Lastly, a method of returning to redock with the ISS to pick up the stranded crew members (or transfer the final crew members) is explained as well as the thruster and ISS loads analysis.

  2. Objective Evaluation Method of Steering Comfort Based on Movement Quality Evaluation of Driver Steering Maneuver

    Institute of Scientific and Technical Information of China (English)

    YANG Yiyong; LIU Yahui; WANG Man; JI Run; JI Xuewu

    2014-01-01

    The existing research of steering comfort mainly focuses on the subjective evaluation, aiming at designing and optimizing the steering system. In the development of steering system, especially the evaluation of steering comfort, the objective evaluation methods considered the kinematic characteristics of driver steering maneuver are not proposed, which means that the objective evaluation of steering cannot be conducted with the evaluation of kinematic characteristics of driver in steering maneuver. In order to propose the objective evaluation methods of steering comfort, the evaluation of steering movement quality of driver is developed on the basis of the study of the kinematic characteristics of steering maneuver. First, the steering motion trajectories of the driver in both comfortable and certain extreme uncomfortable operation conditions are detected using the Vicon motion capture system. The operation conditions are under the restrictions of the vertical height and horizontal distance between steering wheel center and the H-point of driver, and the steering resisting torque else. Next, the movement quality evaluation of driver steering maneuver is assessed using twelve kinds of evaluation indices based on the kinematic analyses of the steering motion trajectories to propose an objective evaluation method. Finally, an integrated discomfort index of steering maneuver is proposed on the basis of the regression analysis of subjective evaluation rating and the movement quality evaluation indices, including the Jerk, Discomfort and Joint Torque indices. The test results show that the proposed integrated discomfort index gives a good fitting with the subjective evaluation of discomfort, which means it can be used to evaluate or predict the discomfort level of steering maneuver. This paper proposes an objective evaluation method of steering comfort based on the movement quality evaluation of driver steering maneuver.

  3. The use of the Heimlich maneuver in near drowning: Institute of Medicine report.

    Science.gov (United States)

    Rosen, P; Stoto, M; Harley, J

    1995-01-01

    The application of the Heimlich maneuver as the initial and perhaps only step for opening the airway in all near-drowning victims has been proposed by Henry Heimlich and Edward Patrick, contrary to current resuscitation guidelines for the treatment of near-drowning victims established by the Emergency Cardiac Care (ECC) Committee of the American Heart Association. Although the Heimlich maneuver is useful for the removal of aspirated solid foreign bodies, there is no evidence that death from drowning is frequently caused by aspiration of a solid foreign body that is not effectively treated by the current ECC recommendations. Furthermore, the evidence is insufficient to support the proposition that the Heimlich maneuver is useful for the removal of aspirated liquid. Moreover, because there is no evidence to support Heimlich's hypothesis that substantial amounts of water are aspirated by near-drowning victims or that such aspirated liquid causes brain damage and death, the available evidence does not support routine use of the Heimlich maneuver in the care of near-drowning victims. The routine use of the Heimlich maneuver for treatment of near drowning raises several concerns: (a) the amount of time it would take to repeat this maneuver and how long this would delay the initiation of artificial ventilation; (b) possible complications of the Heimlich maneuver, especially if the near drowning is associated with a cervical fracture; and (c) the prospect of teaching rescue workers a different protocol than that which is taught at present for resuscitating victims of cardiopulmonary arrest from all causes other than near drowning.(ABSTRACT TRUNCATED AT 250 WORDS)

  4. Comparison of Mallampati test with lower jaw protrusion maneuver in predicting difficult laryngoscopy and intubation

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    Muhammad Irfan Ul Haq

    2013-01-01

    Full Text Available Background: Failure to maintain a patent airway is one of the commonest causes of anesthesia-related morbidity and mortality. Many protocols, algorithms, and different combinations of tested methods for airway assessment have been developed to predict difficult laryngoscopy and intubation. The reported incidence of a difficult intubation varies from 1.5% to 13%. The objective of this study was to compare Mallampati test (MT with lower jaw protrusion (LJP maneuver in predicting difficult laryngoscopy and intubation. Materials and Methods: Seven hundred and sixty patients were included in the study. All the patients underwent MT and LJP maneuver for their airway assessment. After a standardized technique of induction of anesthesia, primary anesthetist performed laryngoscopy and graded it according to the grades described by Cormack and Lehane. Sensitivity, specificity, accuracy, and positive predictive value (PPV and negative predictive value (NPV were calculated for both these tests with 95% confidence interval (CI using conventional laryngoscopy as gold standard. Area under curve was also calculated for both, MT and LJP maneuver. A P < 0.05 was taken as significant. Results: LJP maneuver had higher sensitivity (95.9% vs. 27.1%, NPV (98.7% vs. 82.0%, and accuracy (90.1% vs. 80.3% when compared to MT in predicting difficult laryngoscopy and intubation. Both tests, however, had similar specificity and PPV. There was marked difference in the positive and negative likelihood ratio between LJP and MT. Similarly, the area under the curve favored LJP maneuver over MT. Conclusion: The results of this study show that LJP maneuver is a better test to predict difficult laryngoscopy and tracheal intubation. We recommend the addition of this maneuver to the routine preoperative evaluation of airway.

  5. Is cardiac autonomic modulation during upper limb isometric contraction and Valsalva maneuver impaired in COPD patients?

    Science.gov (United States)

    Goulart, Cássia da Luz; Cabiddu, Ramona; Schneiders, Paloma de Borba; Antunes San Martin, Elisabete; Trimer, Renata; Borghi-Silva, Audrey; da Silva, Andréa Lúcia Gonçalves

    2017-01-01

    Purpose To evaluate the heart rate variability (HRV) indices and heart rate (HR) responses during isometric contraction (IC) and Valsalva maneuver (VM) in COPD patients. Methods Twenty-two stable moderate to severe COPD patients were evaluated. R-R intervals were recorded (monitor Polar® S810i) during dominant upper limb IC (2 minutes). Stable signals were analyzed by Kubios HRV® software. Indices of HRV were computed in the time domain (mean HR; square root of the mean squared differences of successive RR intervals [RMSSD] and HRV triangular index [RR tri index]) and in the frequency domain (high frequency [HF]; low frequency [LF] and LF/HF ratio). The HR responses were evaluated at rest, at the peak and at the nadir of the VM (15 seconds). The Valsalva index was also calculated. Results During IC: time domain indices (mean HR increased [P=0.001], RMSSD, and RR tri index decreased [P=0.005 and P=0.005, respectively]); frequency domain indices (LF increased [P=0.033] and HF decreased [P=0.002]); associations were found between forced expiratory volume in 1 second (FEV1) vs RMSSD (P=0.04; r=−0.55), FEV1 vs HR (P=0.04; r=−0.48), forced vital capacity (FVC) vs RMSSD (P=0.05; r=−0.62), maximum inspiratory pressure (MIP) vs HF (P=0.02; r=0.68). FEV1 and FVC justified 30% of mean HR. During VM: HR increased (P=0.01); the nadir showed normal bradycardic response; the Valsalva index was =0.7. Conclusion COPD patients responded properly to the upper limb IC and to the VM; however, HR recovery during VM was impaired in these patients. The severity of the disease and MIP were associated with increased parasympathetic modulation and higher chronotropic response.

  6. 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

  7. Attitude estimation and maneuvering for autonomous obstacle avoidance by miniature air vehicles

    Science.gov (United States)

    Hall, James K.

    Utilizing the Euler-Rodrigues symmetric parameters (attitude quaternion) to describe vehicle orientation, we develop a multiplicative, nonlinear (extended) variation of the Kalman filter (MEKF) to fuse data from low-cost sensors. The sensor suite is comprised of gyroscopes, accelerometers, and a GPS receiver. In contrast to the common approach of using the complete vehicle attitude as the quantities to be estimated, our filter states consist of the three components of an attitude error vector. In parallel with the time update of the attitude error estimate, we utilize the gyroscope measurements for the time propagation of the attitude quaternion. The accelerometer and the GPS sensors are used independently for the measurement update portion of the Kalman filter. For both sensors, a vector arithmetic approach is used to determine the attitude error vector. Following each measurement update, a multiplicative reset operation moves the attitude error information from the filter state into the attitude estimate. This reset operation utilizes quaternion algebra to implicitly maintain the unity-norm constraint. We demonstrate the effectiveness of our attitude estimation algorithm through flight simulations and flight tests of aggressive maneuvers such as loops and small-radius circles. We implement an approach to acrobatic maneuvering for miniature air vehicles (MAVs) using time-parameterized attitude trajectory generation and an associated attitude tracking control law. We designed two methodologies, polynomial and trigonometric, for creating functions that specify pitch and roll angles as a function of time. For both approaches, the functions are constrained by the maneuver boundary conditions of aircraft position and velocity. We construct a trajectory tracking feedback control law to regulate aircraft orientation throughout the maneuvers. The trajectory generation algorithm was used to construct several maneuvers and trajectory tracking control law successfully

  8. Effects of manual rib-cage compression versus PEEP-ZEEP maneuver on respiratory system compliance and oxygenation in patients receiving mechanical ventilation.

    Science.gov (United States)

    Santos, Flavio Renato Antunes Dos; Schneider Júnior, Luiz Carlos; Forgiarini Junior, Luiz Alberto; Veronezi, Jefferson

    2009-06-01

    Patients unable to perform breathing functions may be submitted to invasive mechanical ventilation. Chest physiotherapy acts directly on the treatment of these patients for the purpose of improving their lung function. The objective of this study was to evaluate the effects of manual rib-cage compression versus the positive end expiratory pressure-zero end expiratory pressure (PEEP-ZEEP) maneuver, on compliance of the respiratory system and oxygenation in patients under invasive mechanical ventilation. A double centric, prospective, randomized and crossover study, with patients under invasive mechanical ventilation, in controlled mode for more than 48 hours was carried out. The protocols of chest physiothe-rapy were randomly applied at an interval of 24 hours. Data of respiratory system compliance and oxygenation were collected before application of the protocols and 30 minutes after. Twelve patients completed the study. Intragroup analysis, for both techniques showed a statistically significant difference in tidal volume (p=0.002), static compliance (p=0.002) and dynamic compliance (p=0.002). In relation to oxygenation, in the group of manual rib-cage compression, peripheral oxygen saturation increased with a significant difference (p=0.011). Manual rib-cage compression and PEEP-ZEEP maneuver have positive clinical effects. In relation to oxygenation we found a favorable behavior of peripheral oxygen saturation in the group of manual rib-cage compression.

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

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    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.

  10. Implementation of an Autonomous Multi-Maneuver Targeting Sequence for Lunar Trans-Earth Injection

    Science.gov (United States)

    Whitley, Ryan J.; Williams, Jacob

    2010-01-01

    Using a fully analytic initial guess estimate as a first iterate, a targeting procedure that constructs a flyable burn maneuver sequence to transfer a spacecraft from any closed Moon orbit to a desired Earth entry state is developed and implemented. The algorithm is built to support the need for an anytime abort capability for Orion. Based on project requirements, the Orion spacecraft must be able to autonomously calculate the translational maneuver targets for an entire Lunar mission. Translational maneuver target sequences for the Orion spacecraft include Lunar Orbit Insertion (LOI), Trans-Earth Injection (TEI), and Trajectory Correction Maneuvers (TCMs). This onboard capability is generally assumed to be supplemental to redundant ground computation in nominal mission operations and considered as a viable alternative primarily in loss of communications contingencies. Of these maneuvers, the ability to accurately and consistently establish a flyable 3-burn TEI target sequence is especially critical. The TEI is the sole means by which the crew can successfully return from the Moon to a narrowly banded Earth Entry Interface (EI) state. This is made even more critical by the desire for global access on the lunar surface. Currently, the designed propellant load is based on fully optimized TEI solutions for the worst case geometries associated with the accepted range of epochs and landing sites. This presents two challenges for an autonomous algorithm: in addition to being feasible, the targets must include burn sequences that do not exceed the anticipated propellant load.

  11. THE EFFECTIVENESS OF SEMONT LIBERATORY MANEUVER IN ACUTE BENINGN PAROXYSMAL POSITIONAL VERTIGO PATIENTS

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    Achyutha Kiran Kumar

    2014-08-01

    Full Text Available Background: People with vestibular dysfunction complain of problems with balance and dizziness which creates a negative impact on the people and affects their quality of life. Medications help in the control of symptoms. There has been an increase in the implementation of many protocols for the rehabilitation of vestibular patients with follow up exercises for the treatment of BPPV. Methods: Thirty BPPV patients were identified by doing Dix- Hall pike positioning and their DHI scores were recorded. All patients were exclusively treated with Semont Liberatory maneuver. The effectiveness of the treatment was documented at 1 week and 1 month. Repeated procedures were performed if necessary. Results: After the treatment session of Semont Liberatory maneuver, the symptoms disappeared in 20 patients and have negative DHI test by 1st week, and of patients have negative DHI test by 1 month. The first success rate was 78% and the total success rate was 89%. Semont Liberatory maneuver also showed decrease in score of DHI [post-test] in 1 month duration. The patient who visited within one week after the onset of symptoms had good prognosis with Semont Liberatory maneuver. This protocol was ineffective in 4 patients. Conclusion: The Semont Liberatory maneuver is a safe and effective technique for treating BPPV patients.

  12. Quick repositioning maneuver for horizontal semicircular canal benign paroxysmal positional vertigo

    Institute of Scientific and Technical Information of China (English)

    Jinrang Li; Pengfei Guo; Shiyu Tian; Keliang Li; Hao Zhang

    2015-01-01

    Objective:To investigate the efficacy of quick repositioning maneuver for horizontal semicircular canal benign paroxysmal positional vertigo (H-BPPV). Methods:Clinical data of 67 patients with H-BPPV who underwent quick repositioning maneuver in our hospital from July 2009 to November 2014 were retrospectively analyzed. The maneuver involved rotating the patient in the axial plane for 180? from the involved side towards contralateral side as quickly as possible. Results:Complete symptom resolution was achieved in 61 patients (91.0%) at one week and in 64 patients (95.5%) at 3 months post-treatment. During the repositioning maneuver process, there were no obvious untoward responses except transient nausea with or without vomiting in a few patients. Conclusion:The results indicate that the quick repositioning maneuver is an easy and effective alternative treatment in the management of H-BPPV. Copyright © 2015 The Authors. Production & hosting by Elsevier (Singapore) Pte Ltd On behalf of PLA General Hospital Department of Otolaryngology Head and Neck Surgery. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

  13. Is it important to repeat the positioning maneuver after the treatment for benign paroxysmal positional vertigo?

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    Alexandra Kolontai de Sousa Oliveira

    2015-04-01

    Full Text Available INTRODUCTION: Benign paroxysmal positional vertigo (BPPV is the most common cause of peripheral vestibular dysfunction.OBJECTIVE: To assess whether the performance of the Dix-Hallpike maneuver after the Epley positioning maneuver has prognostic value in the evolution of unilateral ductolithiasis of posterior semicircular canal.METHODS: A prospective cohort study in monitored patients at otoneurology ambulatory with a diagnosis of BPPV; they were submitted to the therapeutic maneuver and then to a retest in order to evaluate the treatment effectiveness; all cases were reassessed one week later and the retest prognostic value was evaluated.RESULTS: A sample of 64 patients which 47 belonging to negative retest group and 17 belonging to positive retest. Performed the maneuver in all patients, the retest presented 51.85% sensitivity, 91.89% specificity, 82.35% positive predictive value and 72.34% negative predictive value.CONCLUSION: The study shows that doing the retest after repositioning maneuver of particles in BPPV is effectual, since it has high specificity.

  14. Variables Affecting Canalith Repositioning Maneuver (CRM Trend for Treating Patients with Benign Paroxysmal Positional Vertigo (BPPV

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    E. Entezari

    2006-07-01

    Full Text Available Background: The purpose of this study was to identify variables affecting outcome in patients with benign paroxysmal positional vertigo (BPPV treated with canalith repositioning maneuver (CRM. Methods: This interventional study was conducted on 58 patients (14 males, 44 females, mean age 48.12+13.22 referred to the Vertigo Rehabilitation Clinic of the Rehabilitation School of Tehran University of Medical Sciences from 2002 to 2004. All patients were treated with CRM. According to the treatment efficacy the patients were allocated in three groups: completely treated, partially treated, and not treated. The effect of factors including age, sex, etiology, duration of BPPV, unilateral or bilateral disease, number of maneuvers, and number of sessions on outcome in patients was evaluated. Results: Forty-nine patients (84.5% were completely cured. Age, sex, etiology, and duration did not significantly affect the treatment outcome. Unilateral BPPV can be treated significantly better than bilateral BPPV. Forty-seven patients who were completely treated needed 1 session and thirty-seven of them required 2 maneuvers. Conclusion: CRM is significantly effective for BPPV treatment. Treating unilateral BPPV is expected to be easier. As most of the patients will be cured by 1 or 2 maneuvers or in 1 session, patients who required more sessions or more maneuvers may not be completely treated.

  15. Effects of hamstring stretching on passive muscle stiffness vary between hip flexion and knee extension maneuvers.

    Science.gov (United States)

    Miyamoto, N; Hirata, K; Kanehisa, H

    2017-01-01

    The purpose of this study was to examine whether the effects of hamstring stretching on the passive stiffness of each of the long head of the biceps femoris (BFl), semitendinosus (ST), and semimembranosus (SM) vary between passive knee extension and hip flexion stretching maneuvers. In 12 male subjects, before and after five sets of 90 s static stretching, passive lengthening measurements where knee or hip joint was passively rotated to the maximal range of motion (ROM) were performed. During the passive lengthening, shear modulus of each muscle was measured by ultrasound shear wave elastography. Both stretching maneuvers significantly increased maximal ROM and decreased passive torque at a given joint angle. Passive knee extension stretching maneuver significantly reduced shear modulus at a given knee joint angle in all of BFl, ST, and SM. In contrast, the stretching effect by passive hip flexion maneuver was significant only in ST and SM. The present findings indicate that the effects of hamstring stretching on individual passive muscles' stiffness vary between passive knee extension and hip flexion stretching maneuvers. In terms of reducing the muscle stiffness of BFl, stretching of the hamstring should be performed by passive knee extension rather than hip flexion. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  16. 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.

  17. Heuber Maneuver in Evaluation of Direct Carotid-Cavernous Fistula

    Science.gov (United States)

    Rajagopal, Rengarajan; Mehta, Neeraj; Saran, Sonal; Khera, Pushpinder S.

    2016-01-01

    Summary Carotid-cavernous fistulas are abnormal communications between the carotid system and the cavernous sinus. Elevated venous pressure produces congestion in the orbit with resultant transudation of fluid and increased intraocular pressure, thereby leading to secondary glaucoma which may result in visual loss. Immediate treatment is hence, warranted in these cases. The planning of endovascular management is dependent on many parameters, the most important of which are the size and location of the fistula. Since these are high-flow fistulas, assessment requires certain manoeuvers. Heuber manoeuver is one of the manoeuvers used to demonstrate the size of the fistula.

  18. Is cardiac autonomic modulation during upper limb isometric contraction and Valsalva maneuver impaired in COPD patients?

    Directory of Open Access Journals (Sweden)

    Goulart CL

    2017-03-01

    Full Text Available Cássia da Luz Goulart,1 Ramona Cabiddu,2 Paloma de Borba Schneiders,1 Elisabete Antunes San Martin,1 Renata Trimer,3 Audrey Borghi-Silva,2 Andréa Lúcia Gonçalves da Silva4,5 1Course of Physiotherapy, University of Santa Cruz do Sul, Rio Grande do Sul, Brazil; 2Cardiopulmonary Physiotherapy Laboratory, Nucleus of Research in Physical Exercise, Federal University of São Carlos, São Carlos, Brazil; 3Department of Physiotherapy, Federal University of Amazonas, Manaus, AM, Brazil; 4Course of Physiotherapy, Department of Health and Physical Education, University of Santa Cruz do Sul, Rio Grande do Sul, Brazil; 5Pulmonary Rehabilitation Program, Santa Cruz Hospital, Santa Cruz do Sul, Rio Grande do Sul, Brazil Purpose: To evaluate the heart rate variability (HRV indices and heart rate (HR responses during isometric contraction (IC and Valsalva maneuver (VM in COPD patients. Methods: Twenty-two stable moderate to severe COPD patients were evaluated. R-R intervals were recorded (monitor Polar® S810i during dominant upper limb IC (2 minutes. Stable signals were analyzed by Kubios HRV® software. Indices of HRV were computed in the time domain (mean HR; square root of the mean squared differences of successive RR intervals [RMSSD] and HRV triangular index [RR tri index] and in the frequency domain (high frequency [HF]; low frequency [LF] and LF/HF ratio. The HR responses were evaluated at rest, at the peak and at the nadir of the VM (15 seconds. The Valsalva index was also calculated. Results: During IC: time domain indices (mean HR increased [P=0.001], RMSSD, and RR tri index decreased [P=0.005 and P=0.005, respectively]; frequency domain indices (LF increased [P=0.033] and HF decreased [P=0.002]; associations were found between forced expiratory volume in 1 second (FEV1 vs RMSSD (P=0.04; r=–0.55, FEV1 vs HR (P=0.04; r=–0.48, forced vital capacity (FVC vs RMSSD (P=0.05; r=–0.62, maximum inspiratory pressure (MIP vs HF (P=0.02; r=0.68. FEV1

  19. The Maneuver Planning Process for the Microwave Anisotropy Probe (MAP) Mission

    Science.gov (United States)

    Mesarch, Michael A.; Andrews, Stephen F.; Bauer, Frank (Technical Monitor)

    2002-01-01

    The Microwave Anisotropy Probe (MAP) mission utilized a strategy combining highly eccentric phasing loops with a lunar gravity assist to provide a zero-cost insertion into a Lissajous orbit about the Sun-Earth/Moon L2 point. Maneuvers were executed at the phasing loop perigees to correct for launch vehicle errors and to target the lunar gravity assist so that a suitable orbit at L2 was achieved. This paper will discuss the maneuver planning process for designing, verifying, and executing MAP's maneuvers. This paper will also describe how commercial off-the-shelf (COTS) tools were used to execute these tasks and produce a command sequence ready for upload to the spacecraft. These COTS tools included Satellite Tool Kit, MATLAB, and Matrix-X.

  20. 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

    This 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 attributes. Five alternative actions involving emergency lateral and speed...... 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...... for the analysis are retrieved from the General Estimates System (GES) crash database for the year 2009. Results show that (i) the nature of the critical event that made the crash imminent influences the choice of crash avoidance maneuvers, (ii) women and elderly have a lower propensity to conduct crash avoidance...

  1. Attitude and Heading Reference System for Small Unmanned Aircraft Collision Avoidance Maneuvers

    Science.gov (United States)

    Murrant, Kevin

    This thesis describes the development of an Attitude and Heading Reference System (AHRS) to sense three-dimensional orientation for collision avoidance control in small unmanned aircraft. Unmanned aircraft are currently restricted to flight in designated airspace due to safety concerns of collision with manned aircraft. Therefore, collision avoidance is necessary to ensure the safety of both aircraft. Technical challenges, mainly in sensor limitations, restrict AHRS performance in attitude estimation during high-g maneuvers. Using sensor filtering techniques and a robust attitude representation, an AHRS suitable for collision avoidance is developed. Acceleration disturbances are reduced using estimates of non-gravitational accelerations including centripetal acceleration and model-based acceleration to improve gravity vector measurement during aircraft maneuvers. Simulation results with a variety of maneuvers deemed challenging for most AHRS are given showing accurate attitude estimates. Flight data from an existing commercial autopilot is compared with the results of the AHRS to demonstrate the validity of the solution with real flight data.

  2. Parallel Processing Based on Ship Maneuvering in Identification of Interaction Force Coefficients

    Institute of Scientific and Technical Information of China (English)

    LIU Xiao-jian; HUANG Guo-liang; DENG De-heng

    2008-01-01

    The parallel processing based on the free running model test was adopted to predict the interac-tion force coefficients (flow straightening coefficient and wake fraction) of ship maneuvering. And the multi-population genetic algorithm (MPGA) based on real coding that can contemporarily process the data of freerunning model and simulation of ship maneuvering was applied to solve the problem. Accordingly the optimalindividual was obtained using the method of genetic algorithm. The parallel processing of multi-populationsolved the prematurity in the identification for single population, meanwhile, the parallel processing of the dataof ship maneuvering (turning motion and zigzag motion) is an attempt to solve the coefficient drift problem.In order to validate the method, the interaction force coefficients were verified by the procedure and thesecoefficients measured were compared with those ones identified. The maximum error is less than 5%, and theidentification is an effective method.

  3. Chaotic attitude and reorientation maneuver for completely liquid-filled spacecraft with flexible appendage

    Institute of Scientific and Technical Information of China (English)

    Baozeng Yue

    2009-01-01

    The present paper investigates the chaotic attitude dynamics and reorientation maneuver for completely viscous liquid-filled spacecraft with flexible appendage. All of the equations of motion are derived by using Lagrangian mechanics and then transformed into a form consisting of an unperturbed part plus perturbed terms so that the system's nonlinear characteristics can be exploited in phase space.Emphases are laid on the chaotic attitude dynamics produced from certain sets of physical parameter values of the spacecraft when energy dissipation acts to derive the body from minor to major axis spin. Numerical solutions of these equations show that the attitude dynamics of liquid-filled flexible spacecraft possesses characteristics common to random, nonperiodic solutions and chaos, and it is demonstrated that the desired reorientation maneuver is guaranteed by using a pair of thruster impulses. The control strategy for reorientation maneuver is designed and the numerical simulation results are presented for both the uncontrolled and controlled spins transition.

  4. Adaptive variable structure control based on backstepping for spacecraft with reaction wheels during attitude maneuver

    Institute of Scientific and Technical Information of China (English)

    SONG Bin; MA Guang-fu; LI Chuan-jiang

    2009-01-01

    An adaptive variable structure control method based on backstepping is proposed for the attitude maneuver problem of rigid spacecraft with reaction wheel dynamics in the presence of uncertain inertia matrix and external disturbances. The proposed control approach is a combination of the backstepping and the adaptive variable structure control. The cascaded structure of the attitude maneuver control system with reaction wheel dynamics gives the advantage for applying the backstepping method to construct Lyapunov functions. The robust stability to external disturbances and parametric uncertainty is guaranteed by the adaptive variable structure control. To validate the proposed control algorithm, numerical simulations using the proposed approach are performed for the attitude maneuver mission of rigid spacecraft with a configuration consisting of four reaction wheels for actuator and three magnetorquers for momentum unloading. Simulation results verify the effectiveness of the proposed control algorithm.

  5. Therapeutic effect of Epley maneuver on patients with posterior semicircular canal in benign paroxysmal positional vertigo

    Directory of Open Access Journals (Sweden)

    Gholamali Dashti-Khadivaki

    2010-06-01

    Full Text Available Background: Benign paroxysmal positional vertigo (BPPV is characterized by brief attacks of vertigo, nausea and/or positional nystagmus during head movements. Epley maneuver is one of the therapeutic processes for these patients and had various results in different studies. The objective of this study was to determine the efficacy of this procedure on treatment of patients with BPPV.Material and Methods: This study was performed from January 2008 till September 2009 in otolaryngology clinic of Khatam teaching hospital in Zahedan. The study was conducted among 67 patients (38 female, 29 male with p-BPPV between the ages of 27 and 68 years old. Epley maneuver with restriction was performed for treatment after diagnosis of BPPV and one week later, results evaluated using the Dix-Hallpike test.Result: 92.5% of patients had positive response to this type of treatment. Conclusions: The study revealed good efficacy of Epley maneuver on patients with BPPV

  6. Attitude maneuver of spacecraft with a variable-speed double-gimbal control moment gyro

    Science.gov (United States)

    Jikuya, Ichiro; Fujii, Kenta; Yamada, Katsuhiko

    2016-10-01

    In this paper, two types of computational procedures are presented for a rest-to-rest spacecraft maneuver using a variable-speed double-gimbal control moment gyro (VSDGCMG). The first procedure is a numerical computational procedure in which a quasi-time-optimal trajectory satisfying several physical constraints is obtained by repeating the Newton's method. The other procedure is an approximate computational procedure in which an analytical solution is obtained by approximately solving a series of linear optimal control problems. The two procedures play complementary roles: the former is suitable for implementation, and the latter can be used to select an initial value for use in the former. The effectiveness of the proposed procedures is demonstrated by plotting the surfaces of maneuvering time for all rotational axes and by plotting time responses for several maneuvering examples.

  7. CLINICAL DIAGNOSIS OF SUBSCAPULARIS TENDON TEAR USING THE BEAR HUG SEMIOLOGICAL MANEUVER

    Science.gov (United States)

    Schiefer, Márcio; Júnior, Yonder Archanjo Ching-San; Silva, Sérgio Maurício; Fontenelle, César; Dias Carvalho, Marcos Genúncio; de Faria, Fabio Garcia; Franco, José Sérgio

    2015-01-01

    Objective: To evaluate the Bear Hug maneuver for clinically diagnosing subscapularis tendon tears, and compare this with other maneuvers described previously (Lift-off, Napoleon and Belly Press). Methods: Forty-nine patients with rotator cuff injuries who had undergone arthroscopy to repair the injury and had previously been assessed using the semiological maneuvers mentioned above were evaluated. Results: The diagnostic values obtained for the Bear Hug test were as follows: sensitivity 75%, specificity 56%, positive predictive value 62%, negative predictive value 70% and accuracy 65%. Conclusion: The highest sensitivity and negative predictive value values were obtained with the Bear Hug test. The highest specificity value was seen with the Lift-off test. The Belly press test gave the greatest specificity, positive predictive and accuracy values. PMID:27047870

  8. A Fully Nonlinear, Dynamically Consistent Numerical Model for Ship Maneuvering in a Seaway

    Directory of Open Access Journals (Sweden)

    Ray-Qing Lin

    2011-01-01

    Full Text Available This is the continuation of our research on development of a fully nonlinear, dynamically consistent, numerical ship motion model (DiSSEL. In this paper we report our results on modeling ship maneuvering in arbitrary seaway that is one of the most challenging and important problems in seakeeping. In our modeling, we developed an adaptive algorithm to maintain dynamical balances numerically as the encounter frequencies (the wave frequencies as measured on the ship varying with the ship maneuvering state. The key of this new algorithm is to evaluate the encounter frequency variation differently in the physical domain and in the frequency domain, thus effectively eliminating possible numerical dynamical imbalances. We have tested this algorithm with several well-documented maneuvering experiments, and our results agree very well with experimental data. In particular, the numerical time series of roll and pitch motions and the numerical ship tracks (i.e., surge, sway, and yaw are nearly identical to those of experiments.

  9. Intraoperative recruitment maneuver reverses detrimental pneumoperitoneum-induced respiratory effects in healthy weight and obese patients undergoing laparoscopy.

    Science.gov (United States)

    Futier, Emmanuel; Constantin, Jean-Michel; Pelosi, Paolo; Chanques, Gerald; Kwiatkoskwi, Fabrice; Jaber, Samir; Bazin, Jean-Etienne

    2010-12-01

    Pulmonary function is impaired during pneumoperitoneum mainly as a result of atelectasis formation. We studied the effects of 10 cm H2O of positive end-expiratory pressure (PEEP) and PEEP followed by a recruitment maneuver (PEEP+RM) on end-expiratory lung volume (EELV), oxygenation and respiratory mechanics in patients undergoing laparoscopic surgery. Sixty consecutive adult patients (30 obese, 30 healthy weight) in reverse Trendelenburg position were prospectively studied. EELV, static elastance of the respiratory system, dead space, and gas exchange were measured before and after pneumoperitoneum insufflation with zero end-expiratory pressure, with PEEP alone, and with PEEP+RM. Results are presented as mean ± SD. Pneumoperitoneum reduced EELV (healthy weight, 1195 ± 405 vs. 1724 ± 774 ml; obese, 751 ± 258 vs. 886 ± 284 ml) and worsened static elastance and dead space in both groups (in all P obese, 364 ml, P < 0.01) with no effect on oxygenation. Compared with PEEP alone, EELV and static elastance were further improved after RM in both groups (P < 0.05), as was oxygenation (P < 0.01). In all patients, RM-induced change in EELV was 16% (P = 0.04). These improvements were maintained 30 min after RM. RM-induced changes in EELV correlated with change in oxygenation (r = 0.42, P < 0.01). RM combined with 10 cm H2O of PEEP improved EELV, respiratory mechanics, and oxygenation during pneumoperitoneum whereas PEEP alone did not.

  10. 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.

  11. Intra-abdominal pressure during swimming.

    Science.gov (United States)

    Moriyama, S; Ogita, F; Huang, Z; Kurobe, K; Nagira, A; Tanaka, T; Takahashi, H; Hirano, Y

    2014-02-01

    The present study aimed to determine the intra-abdominal pressure during front crawl swimming at different velocities in competitive swimmers and to clarify the relationships between stroke indices and changes in intra-abdominal pressure. The subjects were 7 highly trained competitive collegiate male swimmers. Intra-abdominal pressure was measured during front crawl swimming at 1.0, 1.2 and 1.4 m · s(-1) and during the Valsalva maneuver. Intra-abdominal pressure was taken as the difference between minimum and maximum values, and the mean of 6 stable front crawl stroke cycles was used. Stroke rate and stroke length were also measured as stroke indices. There were significant differences in stroke rate among all velocities (P swimming velocity. These findings do not appear to support the effectiveness of trunk training performed by competitive swimmers aimed at increasing intra-abdominal pressure. © Georg Thieme Verlag KG Stuttgart · New York.

  12. A Study of Maneuvering Control for an Air Cushion Vehicle Based on Back Propagation Neural Network

    Institute of Scientific and Technical Information of China (English)

    LU Jun; HUANG Guo-liang; LI Shu-zhi

    2009-01-01

    A back propagation (BP) neural network mathematical model was established to investigate the maneuvering control of an air cushion vehicle (ACV). The calculation was based on four-freedom-degree model experiments of hydrodynamics and aerodynamics. It is necessary for the ACV to control the velocity and the yaw rate as well as the velocity angle at the same time. The yaw rate and the velocity angle must be controlled correspondingly because of the whipping, which is a special characteristic for the ACV. The calculation results show that it is an efficient way for the ACV's maneuvering control by using a BP neural network to adjust PID parameters online.

  13. ADAPTIVE PRACTICAL OUTPUT MANEUVERING CONTROL FOR A CLASS OF NONLINEAR SYSTEMS

    Institute of Scientific and Technical Information of China (English)

    Chunling WEI; Yuqiang WU; Shumin FEI

    2007-01-01

    This paper deals with the adaptive practical output maneuvering control problems for a class of nonlinear systems with uncontrollable unstable linearization.The objective is to design a smooth adaptive maneuvering controller to solve the geometric and dynamic tasks with an arbitrary small steady tracking error.The method of adding a power integrator and the robust recursive design technique are employed to force the system output to track a desired path and make the tracking speed to follow a desired speed along the path.An example is considered and simulation results are given.The proposed design procedure can be illustrated by the use of this example.

  14. Operationally optimal maneuver strategy for spacecraft injected into sub-geosynchronous transfer orbit

    Science.gov (United States)

    Kiran, B. S.; Singh, Satyendra; Negi, Kuldeep

    The GSAT-12 spacecraft is providing Communication services from the INSAT/GSAT system in the Indian region. The spacecraft carries 12 extended C-band transponders. GSAT-12 was launched by ISRO’s PSLV from Sriharikota, into a sub-geosynchronous Transfer Orbit (sub-GTO) of 284 x 21000 km with inclination 18 deg. This Mission successfully accomplished combined optimization of launch vehicle and satellite capabilities to maximize operational life of the s/c. This paper describes mission analysis carried out for GSAT-12 comprising launch window, orbital events study and orbit raising maneuver strategies considering various Mission operational constraints. GSAT-12 is equipped with two earth sensors (ES), three gyroscopes and digital sun sensor. The launch window was generated considering mission requirement of minimum 45 minutes of ES data for calibration of gyros with Roll-sun-pointing orientation in T.O. Since the T.O. period was a rather short 6.1 hr, required pitch biases were worked out to meet the gyro-calibration requirement. A 440 N Liquid Apogee Motor (LAM) is used for orbit raising. The objective of the maneuver strategy is to achieve desired drift orbit satisfying mission constraints and minimizing propellant expenditure. In case of sub-GTO, the optimal strategy is to first perform an in-plane maneuver at perigee to raise the apogee to synchronous level and then perform combined maneuvers at the synchronous apogee to achieve desired drift orbit. The perigee burn opportunities were examined considering ground station visibility requirement for monitoring the burn. Two maneuver strategies were proposed: an optimal five-burn strategy with two perigee burns centered around perigee#5 and perigee#8 with partial ground station visibility and three apogee burns with dual station visibility, a near-optimal five-burn strategy with two off-perigee burns at perigee#5 and perigee#8 with single ground station visibility and three apogee burns with dual station visibility

  15. Pump Fed Propulsion for Mars Ascent and Other Challenging Maneuvers

    Energy Technology Data Exchange (ETDEWEB)

    Whitehead, J C

    2007-05-09

    Returning Mars geology samples to Earth within science mission budgets requires a miniature launch vehicle (100-200 kg) for ascending from Mars to an orbital rendezvous. A Mars Ascent Vehicle must deliver a velocity change exceeding 4 km/s within minutes, entirely outside the capabilities of satellite propulsion. A possible solution is to scale down liquid launch vehicle principles to achieve stage propellant mass fractions near 90 percent. Feeding a high-pressure engine from thin-walled low pressure tanks permits stage hardware to be sufficiently lightweight and compact, if very high performance pumps can be made available. NASA's Mars Technology Program has funded refinement and testing of a miniature piston pump, powered by reacted propellant. A pump-fed bipropellant rocket stage remains to be developed. The technology could also benefit other future lunar and planetary science programs.

  16. Increased inspiratory esophagogastric junction pressure in systemic sclerosis: An add-on to antireflux barrier

    Science.gov (United States)

    Nobre e Souza, Miguel Ângelo; Bezerra, Patrícia Carvalho; Nobre, Rivianny Arrais; Holanda, Esther Studart da Fonseca; dos Santos, Armênio Aguiar

    2015-01-01

    AIM: To investigate crural diaphragm (CD) function in systemic sclerosis (SSc) using high-resolution manometry and standardized inspiratory maneuvers. METHODS: Eight SSc volunteers (average age, 40.1 years; one male) and 13 controls (average age, 32.2 years; six males) participated in the study. A high-resolution manometry/impedance system measured the esophagus and esophagogastric junction (EGJ) pressure profile during swallows and two respiratory maneuvers: sinus arrhythmia maneuver (SAM; the average of six EGJ peak pressures during 5-s deep inhalations) and threshold maneuver (TM; the EGJ peak pressures during forced inhalation under 12 and 24 cmH2O loads). Inspiratory diaphragm lowering (IDL) was taken as the displacement of the EGJ high-pressure zone during the SAM. RESULTS: SSc patients had lower mean lower esophageal sphincter pressure than controls during normal breathing (19.7 ± 2.8 mmHg vs 32.2 ± 2.7 mmHg, P = 0.007). Sinus arrhythmia maneuver pressure was higher in SSc patients than in controls (142.6 ± 9.4 mmHg vs 104.6 ± 13.8 mmHg, P = 0.019). Sinus arrhythmia maneuver pressure normalized to IDL was also higher in SSc patients than in controls (83.8 ± 13.4 mmHg vs 37.5 ± 6.9 mmHg, P = 0.005). Threshold maneuver pressures normalized to IDL were also greater in SSc patients than in controls (TM 12 cmH2O: 85.1 ± 16.4 mmHg vs 43.9 ± 6.3 mmHg, P = 0.039; TM 24 cmH2O: 85.2 ± 16.4 mmHg vs 46.2 ± 6.6 mmHg, P = 0.065). Inspiratory diaphragm lowering in SSc patients was less than in controls (2.1 ± 0.3 cm vs 3 ± 0.2 cm, P = 0.011). CONCLUSION: SSc patients had increased inspiratory EGJ pressure. This is an add-on to EGJ pressure and indicates that the antireflux barrier can be trained. PMID:25717239

  17. Preparing GMAT for Operational Maneuver Planning of the Advanced Composition Explorer (ACE)

    Science.gov (United States)

    Qureshi, Rizwan Hamid; Hughes, Steven P.

    2014-01-01

    The General Mission Analysis Tool (GMAT) is an open-source space mission design, analysis and trajectory optimization tool. GMAT is developed by a team of NASA, private industry, public and private contributors. GMAT is designed to model, optimize and estimate spacecraft trajectories in flight regimes ranging from low Earth orbit to lunar applications, interplanetary trajectories and other deep space missions. GMAT has also been flight qualified to support operational maneuver planning for the Advanced Composition Explorer (ACE) mission. ACE was launched in August, 1997 and is orbiting the Sun-Earth L1 libration point. The primary science objective of ACE is to study the composition of both the solar wind and the galactic cosmic rays. Operational orbit determination, maneuver operations and product generation for ACE are conducted by NASA Goddard Space Flight Center (GSFC) Flight Dynamics Facility (FDF). This paper discusses the entire engineering lifecycle and major operational certification milestones that GMAT successfully completed to obtain operational certification for the ACE mission. Operational certification milestones such as gathering of the requirements for ACE operational maneuver planning, gap analysis, test plans and procedures development, system design, pre-shadow operations, training to FDF ACE maneuver planners, shadow operations, Test Readiness Review (TRR) and finally Operational Readiness Review (ORR) are discussed. These efforts have demonstrated that GMAT is flight quality software ready to support ACE mission operations in the FDF.

  18. 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.

  19. 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... conditions, upon which the maneuvering information is based, are varied: (1) Calm weather—wind 10 knots or... calculations; (4) Simulations; (5) Information established from another vessel of similar hull form,...

  20. Perception model analysis of flight simulator motion for a decrab maneuver

    NARCIS (Netherlands)

    Groen, E.L.; Smaïli, M.H.; Hosman, R.J.A.W.

    2007-01-01

    In this flight simulator study, eleven pilots rated their motion perception during a series of decrab maneuvers of a twin-engine passenger aircraft. Simulator yaw, sway, and roll motion were varied independently to examine their relative contribution to the pilots’ judgments. In one set of condition

  1. Focus-before-detection Methods for Radar Detection of Near Space High-maneuvering Aircrafts

    Directory of Open Access Journals (Sweden)

    Xu Jia

    2017-06-01

    Full Text Available Recently emerging, high maneuvering near space targets have many characteristics that differ from conventional targets, like ultra-high speed, high-maneuverability, ultra-far range, low Radar Cross Section (RCS, plasma sheath, ionosphere layer pollution, and cosmic ray interference. Based on general signal modeling for near space targets of ground-based, airborne, and spaceborne radars, this paper proposes novel focus-before-detection methods with respect to a distributed radar network, multi-dimensions, multiple targets, micro motion, varied model, and non-parametric processing. The proposed FBD based methods can effectively suppress the strong ionosphere layer pollution and active jamming, as well as problems like the scaled effect of echoes, arbitrary motion, aperture fill time, sparse sub-band frequency synthesis, across range cell, across Doppler cell, and across beam width. The proposed Focus-Before-Detection (FBD based methods can remarkably improve the signal processing performance on target detection, parameter estimation, maneuver tracking, high-resolution imaging, feature extraction, and target recognition. Additionally, they are suitable for both high maneuvering near space targets and conventional targets, and can be applied for both new-generation radars and conventional targets. Therefore, the proposed FBD based methods for high maneuvering near space target detection have both important academic research value and impact a wide variety of applications.

  2. Effect of Driver Scope Awareness in the Lane Changing Maneuvers Using Cellular Automaton Model

    Directory of Open Access Journals (Sweden)

    Kohei Arai

    2013-07-01

    Full Text Available This paper investigated the effect of drivers’ visibility and their perception (e.g., to estimate the speed and arrival time of another vehicle on the lane changing maneuver. The term of scope awareness was used to describe the visibility required by the driver to make a perception about road condition and the speed of vehicle that exist in that road. A computer simulation model was conducted to show this driver awareness behavior. This studying attempt to precisely catching the lane changing behavior and illustrate the scope awareness parameter that reflects driver behavior. This paper proposes a simple cellular automata model for studying driver visibility effects of lane changing maneuver and driver perception of estimated speed. Different values of scope awareness were examined to capture its effect on the traffic flow. Simulation results show the ability of this model to capture the important features of lane changing maneuver and revealed the appearance of the short-thin solid line jam and the wide solid line jam in the traffic flow as the consequences of lane changing maneuver.

  3. 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 (I

  4. An optimal fuzzy PID control approach for docking maneuver of two spacecraft: Orientational motion

    Directory of Open Access Journals (Sweden)

    A. Kosari

    2017-02-01

    Full Text Available This paper describes a scheme for a Fuzzy-Proportional Integral Derivative (FPID controller based on genetic algorithm (GA, in a docking maneuver of two spacecraft. The docking maneuver consists of two parts: translation and orientation. Euler’s gyroscopic equation is applied to obtain governing equations of orientational phase. Here, a designed fuzzy-PID controller for stabilization purpose of orientational phase of a docking maneuver is presented based on the Single Input Fuzzy Inference Motor (SIFIMs dynamically connected Preferrer Fuzzy Inference Motor (PFIM. This fuzzy-PID controller takes the error signal of Euler’s angles and the error of angular velocities of the chaser as its input items, and the driving force as its output. The parameters of the controller are ascertained by using a genetic algorithm. Conflicting objective functions (which their 3D pareto frontiers are obtained by Multi-objective Genetic Algorithm (MOGA are distance errors from the set point, angle errors from the set point, and control efforts. Optimization constraint is maximal of the momentum produced by momentum wheels. The result of optimum point demonstrates that the designed controller makes an efficient performance in the orientational phase of the chaser spacecraft. Compared to similar works, some of system parameters like settling time are improved and overshoot (as a critical parameter in docking maneuver is decreased.

  5. Four-Impulsive Rendezvous Maneuvers for Spacecrafts in Circular Orbits Using Genetic Algorithms

    Directory of Open Access Journals (Sweden)

    Denilson Paulo Souza dos Santos

    2012-01-01

    Full Text Available Spacecraft maneuvers is a very important topic in aerospace engineering activities today. In a more generic way, a spacecraft maneuver has the objective of transferring a spacecraft from one orbit to another, taking into account some restrictions. In the present paper, the problem of rendezvous is considered. In this type of problem, it is necessary to transfer a spacecraft from one orbit to another, but with the extra constraint of meeting another spacecraft when reaching the final orbit. In particular, the present paper aims to analyze rendezvous maneuvers between two coplanar circular orbits, seeking to perform this transfer with lowest possible fuel consumption, assuming that this problem is time-free and using four burns during the process. The assumption of four burns is used to represent a constraint posed by a real mission. Then, a genetic algorithm is used to solve the problem. After that, a study is made for a maneuver that will make a spacecraft to encounter a planet, in order to make a close approach that will change its energy. Several simulations are presented.

  6. Vertigo during the Epley maneuver and success rate in patients with BPPV.

    Science.gov (United States)

    Fyrmpas, Georgios; Barkoulas, Eustathios; Haidich, Anna Bettina; Tsalighopoulos, Miltiadis

    2013-09-01

    To investigate whether reported vertigo during the Epley maneuver predicts therapeutic success in patients with benign paroxysmal positioning vertigo of the posterior semicircular canal (pc-BPPV). Fifty consecutive adult patients with pc-BPPV, based on a positive Dix-Hallpike test (DHT), were treated with the Epley maneuver and retested after 2 days. Patients were asked to report the presence of vertigo upon assuming each of the four positions of the maneuver. Thirty seven patients (74 %) were treated successfully in one session. Twenty out of 23 patients who reported vertigo at turning the head to the opposite side (2nd position) had a negative DHT on follow-up. These patients had a higher chance of a successful outcome compared to patients who did not report vertigo in the 2nd position (Odds ratio 5.3, 95 % CI: 1.3-22.2, p = 0.022). Report of vertigo at the other positions was not associated with the outcome. Report of vertigo at the second position of a single modified Epley maneuver is associated with therapeutic success.

  7. "Roller coaster maneuver via lateral orbital approach" for reduction of isolated zygomatic arch fractures.

    Science.gov (United States)

    Pilanci, Ozgur; Basaran, Karaca; Datli, Asli; Kuvat, Samet Vasfi

    2013-11-01

    Numerous techniques have been reported for the reduction of zygomatic arch fractures. In this article, we aimed to describe a technique we named as "roller coaster maneuver via lateral orbital approach" to closed reduction of the isolated-type zygomatic arch fractures. Surgical outcomes of 14 patients treated with this method were outlined.

  8. Using Pontryagin maximum principle for parametrical identification of ship maneuvering mathematical model

    Directory of Open Access Journals (Sweden)

    Uri UDIN

    2014-06-01

    Full Text Available This article proposes usage of Pontryagin maximum principle for parametrical identification of mathematical vessel’s model. Proposed method has a special perspective for identification in real time mode, when the parameters identified can be used for forecasting of coming maneuvers.

  9. Evaluation of Discrimination Technologies and Classification Results Live Site Demonstration: Former Waikoloa Maneuver Area

    Science.gov (United States)

    2015-06-01

    investigated to ensure that all TOI were recovered. 15. SUBJECT TERMS MetalMapper, UX -Analyze, UXO, Former Waikoloa Maneuver Area, discrimination...26 5.7 Munitions Debris Management ................................................................................. 27 6.0...conditions. • Investigate in cooperation with regulators and program managers how classification technologies can be implemented in munitions and

  10. Ground crewmen maneuver the Helios Prototype flying wing on its ground support dolly during function

    Science.gov (United States)

    2001-01-01

    Ground crewmen maneuver AeroVironment's solar-powered Helios Prototype flying wing on its ground support dolly during functional checkouts prior to its first flights under solar power from the U.S. Navy's Pacific Missile Range Facility on Kaua'i, Hawaii.

  11. Optimized routing on agricultural fields by minimizing maneuvering and servicing time

    NARCIS (Netherlands)

    Spekken, M.; Bruin, de S.

    2013-01-01

    Agricultural machines spend a significant part of their time on non-productive operations such as maneuvering near the boundaries of the field and loading or offloading of inputs or outputs (here referred to as servicing). This paper integrates existing methods for route optimization so as to minimi

  12. Optimized routing on agricultural fields by minimizing maneuvering and servicing time

    NARCIS (Netherlands)

    Spekken, M.; Bruin, de S.

    2013-01-01

    Agricultural machines spend a significant part of their time on non-productive operations such as maneuvering near the boundaries of the field and loading or offloading of inputs or outputs (here referred to as servicing). This paper integrates existing methods for route optimization so as to

  13. Dynamics and control of flexible spacecraft during and after slewing maneuvers

    Science.gov (United States)

    Kakad, Yogendra P.

    1989-01-01

    The dynamics and control of slewing maneuvers of NASA Spacecraft COntrol Laboratory Experiment (SCOLE) are analyzed. The control problem of slewing maneuvers of SCOLE is formulated in terms of an arbitrary maneuver about any given axis. The control system is developed for the combined problem of rigid-body slew maneuver and vibration suppression of the flexible appendage. The control problem formulation incorporates the nonlinear dynamical equations derived previously, and is expressed in terms of a two-point boundary value problem utilizing a quadratic type of performance index. The two-point boundary value problem is solved as a hierarchical control problem with the overall system being split in terms of two subsystems, namely the slewing of the entire assembly and the vibration suppression of the flexible antenna. The coupling variables between the two dynamical subsystems are identified and these two subsystems for control purposes are treated independently in parallel at the first level. Then the state-space trajectory of the combined problem is optimized at the second level.

  14. Control of a high beta maneuvering reentry vehicle using dynamic inversion.

    Energy Technology Data Exchange (ETDEWEB)

    Watts, Alfred Chapman

    2005-05-01

    The design of flight control systems for high performance maneuvering reentry vehicles presents a significant challenge to the control systems designer. These vehicles typically have a much higher ballistic coefficient than crewed vehicles like as the Space Shuttle or proposed crew return vehicles such as the X-38. Moreover, the missions of high performance vehicles usually require a steeper reentry flight path angle, followed by a pull-out into level flight. These vehicles then must transit the entire atmosphere and robustly perform the maneuvers required for the mission. The vehicles must also be flown with small static margins in order to perform the required maneuvers, which can result in highly nonlinear aerodynamic characteristics that frequently transition from being aerodynamically stable to unstable as angle of attack increases. The control system design technique of dynamic inversion has been applied successfully to both high performance aircraft and low beta reentry vehicles. The objective of this study was to explore the application of this technique to high performance maneuvering reentry vehicles, including the basic derivation of the dynamic inversion technique, followed by the extension of that technique to the use of tabular trim aerodynamic models in the controller. The dynamic inversion equations are developed for high performance vehicles and augmented to allow the selection of a desired response for the control system. A six degree of freedom simulation is used to evaluate the performance of the dynamic inversion approach, and results for both nominal and off nominal aerodynamic characteristics are presented.

  15. 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.)

  16. 33 CFR 83.34 - Maneuvering and warning signals (Rule 34).

    Science.gov (United States)

    2010-07-01

    ... SECURITY INLAND NAVIGATION RULES RULES Sound and Light Signals § 83.34 Maneuvering and warning signals (Rule 34). (a) Whistle signals. When power-driven vessels are in sight of one another and meeting or... propulsion”. (2) Upon hearing the one or two blast signal of the other shall, if in agreement, sound the same...

  17. The Relationship between Submental Surface Electromyography and Hyo-Laryngeal Kinematic Measures of Mendelsohn Maneuver Duration

    Science.gov (United States)

    Azola, Alba M.; Greene, Lindsey R.; Taylor-Kamara, Isha; Macrae, Phoebe; Anderson, Cheryl; Humbert, Ianessa A.

    2015-01-01

    Purpose: The Mendelsohn Maneuver (MM) is a commonly prescribed technique that is taught to individuals with dysphagia to improve swallowing ability. Due to cost and safety concerns associated with videofluoroscopy (VFS) use, submental surface electromyography (ssEMG) is commonly used in place of VFS to train the MM in clinical and research…

  18. The Mentorship Course of Action: Increasing African American Interest in the Maneuver Branches.

    Science.gov (United States)

    2011-06-10

    which provides the remaining 38 percent of new officers a year, falls under the command of the Infantry School at Fort Benning, Georgia (Wardinski, Lyle...Course to visit their alma maters and espouse the values of the maneuver branches and ―emphasize better communication skills training at

  19. 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 (I

  20. Using Transcutaneous Laryngeal Ultrasonography (TLUSG) to Assess Post-thyroidectomy Patients' Vocal Cords: Which Maneuver Best Optimizes Visualization and Assessment Accuracy?

    Science.gov (United States)

    Wong, Kai-Pun; Woo, Jung-Woo; Li, Jason Yu-Yin; Lee, Kyu Eun; Youn, Yeo Kyu; Lang, Brian Hung-Hin

    2016-03-01

    To assess vocal cord (VC) movement with transcutaneous laryngeal ultrasound (TLUSG), three maneuvers, namely passive (quiet respiration), active (phonation), and Valsalva maneuvers have been described. It remains unclear which maneuver or using more maneuvers provides better visualization and assessment accuracy. We prospectively evaluated 342 post-thyroidectomy patients from two centers. They underwent TLUSG with direct laryngoscopic (DL) validation afterwards. During TLUSG, patients were instructed to perform all three maneuvers (passive, active, and Valsalva). VC visualization rate and accuracy between three maneuvers were compared. Visualization rate tended to be higher in Valsalva maneuver than that in other two maneuvers (92.1% vs. passive: 91.5%; active: 89.8%). While 19 patients had post-operative VC palsy, passive maneuver had lower test specificity than active (94.3 vs. 97.6%, p = 0.01) and Valsalva maneuvers (94.3 vs. 97.4%, p = 0.02). In assessable VCs, passive maneuver has a higher ability to differentiate between mobile VCs and VC palsy (Area under ROC curve--passive: 0.942, active: 0.863, Valsalva: 0.893). TLUSG with more maneuvers did not improve sensitivity or specificity. On applying TLUSG as a screening tool (i.e., only selected patient with "unassessable" VCs or VCP on TLUSG for DL), Valsalva maneuver (85.96%) saved more patients from DL than passive (81.87%) or active (84.81%) maneuver. Passive maneuver has a higher ability to differentiate VC palsy from normal. Using TLUSG as a screening tool, Valsalva was the preferred maneuver as it was more specific, had high visualization rate, and saved more patients from DL.

  1. 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.

  2. Non-Toxic Orbiter Maneuvering System (OMS) and Reaction Control System

    Science.gov (United States)

    Hurlbert, Eric A.; Nicholson, Leonard S. (Technical Monitor)

    1999-01-01

    NASA is pursuing the technology and advanced development of a non-toxic (NT) orbital maneuvering system (OMS) and reaction control system (RCS) for shuttle upgrades, RLV, and reusable first stages. The primary objectives of the shuttle upgrades program are improved safety, improved reliability, reduced operations time and cost, improved performance or capabilities, and commonality with future space exploration needs. Non-Toxic OMS/RCS offers advantages in each of these categories. A non-toxic OMS/RCS eliminates the ground hazards and the flight safety hazards of the toxic and corrosive propellants. The cost savings for ground operations are over $24M per year for 7 flights, and the savings increase with increasing flight rate up to $44M per year. The OMS/RCS serial processing time is reduced from 65 days to 13 days. The payload capability can be increased up to 5100 Ibms. The non-toxic OMS/RCS also provides improved space station reboost capability up to 20 nautical miles over the current toxic system of 14 nautical miles. A NT OMS/RCS represents a clear advancement in the SOA over MMH/NTO. Liquid oxygen and ethanol are clean burning, high-density propellants that provide a high degree of commonality with other spacecraft subsystems including life support, power, and thermal control, and with future human exploration and development of space missions. The simple and reliable pressure-fed design uses sub-cooled liquid oxygen at 250 to 350 psia, which allows a propellant to remain cryogenic for longer periods of time. The key technologies are thermal insulation and conditioning techniques are used to maintain the sub-cooling. Phase I successfully defined the system architecture, designed an integrated OMS/RCS propellant tank, analyzed the feed system, built and tested the 870 lbf RCS thrusters, and tested the 6000 lbf OMS engine. Phase 11 is currently being planned for the development and test of full-scale prototype of the system in 1999 and 2000

  3. The cerebro-cardiovascular response to periodic squat-stand maneuvers in healthy subjects: a time-domain analysis.

    Science.gov (United States)

    Barnes, Sam C; Ball, Naomi; Haunton, Victoria Joanna; Robinson, Thompson G; Panerai, Ronney B

    2017-09-08

    Squat-stand maneuvers (SSMs) have been used to improve the coherence of transfer function analysis (TFA) estimates during the assessment of dynamic cerebral autoregulation (dCA). There is a need to understand the influence of peripheral changes resulting from SSMs on cerebral blood flow, which might confound estimates of dCA. 29 healthy subjects underwent recordings at rest (5 min standing) and 15 SSMs (0.05Hz). Heart rate (3-lead ECG), end-tidal CO2 (capnography), blood pressure (Finometer), cerebral blood velocity (CBV, transcranial Doppler, MCA) and the angle of the thigh (tilt sensor) were measured continuously. The response of CBV to SSMs was decomposed into the relative contributions of mean arterial pressure (MAP), resistance area product (RAP) and critical closing pressure (CrCP). Upon squatting, a rise in MAP (83.6 ± 21.1 % contribution) is followed by increased CBV. A dCA response can be detected, determined by adjustments in RAP and CrCP (left hemisphere) with peak contributions of 24.8 ± 12.7 % and 27.4 ± 22.8 %, respectively, at different times during SSMs. No interhemispheric differences were detected. During standing, the contributions of MAP, RAP and CrCP change considerably. The changes of CBV subcomponents during repeated SSMs indicate a complex response of CBVms. to SSMs that can only be partially explained by myogenic mechanis More work is needed to clarify the potential contribution of other co-factors, such as breath-to-breath changes in pCO2, HR, stroke volume and the neurogenic component of dynamic CA. Copyright © 2017, American Journal of Physiology-Heart and Circulatory Physiology.

  4. 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.

  5. The predictive value of Muller maneuver in REM-dependent obstructive sleep apnea.

    Science.gov (United States)

    Ozcan, Kursat Murat; Ozcan, Muge; Ozdogan, Fatih; Hizli, Omer; Dere, Huseyin; Unal, Adnan

    2013-09-01

    To our knowledge, no studies up to date have investigated the correlation of rapid eye movement (REM) dependent obstructive sleep apnea syndrome (OSAS) and Muller maneuver. The aim of this study is to investigate whether REM-dependent OSAS is predicted by the findings of the Muller maneuver. The study was conducted on 149 patients with witnessed apnea and daytime sleepiness. Muller maneuver was performed to all patients and the obstruction site was determined using a five-point scale. Then, polysomnography of the patient was obtained and the apnea-hypopnea indexes were determined in total sleep time, REM-dependent sleep and non-REM-dependent sleep. The correlations between the Muller maneuver findings and polysomnographic data were analyzed. The ages of the patients included in the study ranged between 25 and 73 years with a mean age of 49.3 ± 10.1 years. Their mean body mass index was 30.8 ± 5.1 kg/m(2) (range 21.9-55.4 kg/m(2)). The patients' mean apnea-hypopnea indexes in total sleep time was 28.1 and ranged between 5.4 and 124.3. REM-dependent OSAS was determined in 49 patients. When the data were analyzed, it was determined that there were no statistically significant correlations between tongue base or lateral pharyngeal band obstruction at the level of hypopharynx and the REM-dependent OSAS. At the level of the soft palate, the obstruction caused by the lateral pharyngeal bands or soft palate and REM dependency did not show any statistically significant correlation (p > 0.05). In conclusion, Muller maneuver does not provide useful data to predict REM dependency of OSAS.

  6. CHANG'E-2 lunar escape maneuvers to the Sun-Earth L2 libration point mission

    Science.gov (United States)

    Liu, Lei; Liu, Yong; Cao, Jianfeng; Hu, Songjie; Tang, Geshi; Xie, Jianfeng

    2014-01-01

    This paper addresses lunar escape maneuvers of the first Chinese Sun-Earth L2 libration point mission by the CHANG'E-2 satellite, which is also the world's first satellite to reach the L2 point from a lunar orbit. The lunar escape maneuvers are heavily constrained by the remaining propellant and the condition of telemetry, track and command, among others. First, these constraints are analyzed and summarized to design a target L2 Lissajous orbit and an initial transfer trajectory. Second, the maneuver mathematical models are studied. The multilevel maneuver schemes which consist of phasing maneuvers and a final lunar escape maneuver are designed for actual operations. Based on the scheme analysis and comparison, the 2-maneuver scheme with a 5.3-h-period phasing orbit is ultimately selected. Finally, the mission status based on the scheme is presented and the control operation results are discussed in detail. The methodology in this paper is especially beneficial and applicable to a future multi-mission instance in the deep space exploration.

  7. 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.

  8. Tracking of Maneuvering Complex Extended Object with Coupled Motion Kinematics and Extension Dynamics Using Range Extent Measurements.

    Science.gov (United States)

    Sun, Lifan; Ji, Baofeng; Lan, Jian; He, Zishu; Pu, Jiexin

    2017-09-22

    The key to successful maneuvering complex extended object tracking (MCEOT) using range extent measurements provided by high resolution sensors lies in accurate and effective modeling of both the extension dynamics and the centroid kinematics. During object maneuvers, the extension dynamics of an object with a complex shape is highly coupled with the centroid kinematics. However, this difficult but important problem is rarely considered and solved explicitly. In view of this, this paper proposes a general approach to modeling a maneuvering complex extended object based on Minkowski sum, so that the coupled turn maneuvers in both the centroid states and extensions can be described accurately. The new model has a concise and unified form, in which the complex extension dynamics can be simply and jointly characterized by multiple simple sub-objects' extension dynamics based on Minkowski sum. The proposed maneuvering model fits range extent measurements very well due to its favorable properties. Based on this model, an MCEOT algorithm dealing with motion and extension maneuvers is also derived. Two different cases of the turn maneuvers with known/unknown turn rates are specifically considered. The proposed algorithm which jointly estimates the kinematic state and the object extension can also be easily implemented. Simulation results demonstrate the effectiveness of the proposed modeling and tracking approaches.

  9. Use of manual alveolar recruitment maneuvers to eliminate atelectasis artifacts identified during thoracic computed tomography of healthy neonatal foals.

    Science.gov (United States)

    Lascola, Kara M; Clark-Price, Stuart C; Joslyn, Stephen K; Mitchell, Mark A; O'Brien, Robert T; Hartman, Susan K; Kline, Kevin H

    2016-11-01

    OBJECTIVE To evaluate use of single manual alveolar recruitment maneuvers (ARMs) to eliminate atelectasis during CT of anesthetized foals. ANIMALS 6 neonatal Standardbred foals. PROCEDURES Thoracic CT was performed on spontaneously breathing anesthetized foals positioned in sternal (n = 3) or dorsal (3) recumbency when foals were 24 to 36 hours old (time 1), 4 days old (time 2), 7 days old (time 3), and 10 days old (time 4). The CT images were collected without ARMs (all times) and during ARMs with an internal airway pressure of 10, 20, and 30 cm H2O (times 2 and 3). Quantitative analysis of CT images measured whole lung and regional changes in attenuation or volume with ARMs. RESULTS Increased attenuation and an alveolar pattern were most prominent in the dependent portion of the lungs. Subjectively, ARMs did not eliminate atelectasis; however, they did incrementally reduce attenuation, particularly in the nondependent portion of the lungs. Quantitative differences in lung attenuation attributable to position of foal were not identified. Lung attenuation decreased significantly (times 2 and 3) and lung volume increased significantly (times 2 and 3) after ARMs. Changes in attenuation and volume were most pronounced in the nondependent portion of the lungs and at ARMs of 20 and 30 cm H2O. CONCLUSIONS AND CLINICAL RELEVANCE Manual ARMs did not eliminate atelectasis but reduced attenuation in nondependent portions of the lungs. Positioning of foals in dorsal recumbency for CT may be appropriate when pathological changes in the ventral portion of the lungs are suspected.

  10. The influence of orolingual pressure on the timing of pharyngeal pressure events.

    Science.gov (United States)

    Steele, Catriona M; Huckabee, Maggie Lee

    2007-01-01

    This study explored the influence of two methods of effortful swallow execution on the timing of pharyngeal pressure events. Participants were asked to either emphasize or minimize tongue-to-palate contact during performance of the maneuver. Twenty healthy participants were evaluated using concurrent submental surface electromyography (sEMG), orolingual manometry, and pharyngeal manometry. Each subject performed three repetitions of three counterbalanced tasks (noneffortful dry swallows, effortful dry swallows with tongue-to-palate emphasis, and effortful dry swallows with tongue-to-palate de-emphasis). Four variables were measured: Onset Lag vs. sEMG Peak, Peak Lag vs. sEMG Peak, Total Duration, and Percent Rise Time to Peak. Compared to noneffortful swallows, the effortful swallow task elicited significantly earlier onsets and peaks of pharyngeal pressures relative to the submental sEMG peak. Total pressure event durations were greater and rise times were significantly shorter. When comparing the two methods of effortful swallow execution, a longer latency to peak proximal pharyngeal pressure was found in the tongue-to-palate emphasis condition. These results support the interpretation that the effortful swallow maneuver involves generation of higher velocity bolus driving forces that propel the bolus into and through the pharynx with greater efficiency and that pressure is then sustained to facilitate more complete bolus clearance.

  11. Application of hybrid methodology to rotors in steady and maneuvering flight

    Science.gov (United States)

    Rajmohan, Nischint

    Helicopters are versatile flying machines that have capabilities that are unparalleled by fixed wing aircraft, such as operating in hover, performing vertical takeoff and landing on unprepared sites. This makes their use especially desirable in military and search-and-rescue operations. However, modern helicopters still suffer from high levels of noise and vibration caused by the physical phenomena occurring in the vicinity of the rotor blades. Therefore, improvement in rotorcraft design to reduce the noise and vibration levels requires understanding of the underlying physical phenomena, and accurate prediction capabilities of the resulting rotorcraft aeromechanics. The goal of this research is to study the aeromechanics of rotors in steady and maneuvering flight using hybrid Computational Fluid Dynamics (CFD) methodology. The hybrid CFD methodology uses the Navier-Stokes equations to solve the flow near the blade surface but the effect of the far wake is computed through the wake model. The hybrid CFD methodology is computationally efficient and its wake modeling approach is nondissipative making it an attractive tool to study rotorcraft aeromechanics. Several enhancements were made to the CFD methodology and it was coupled to a Computational Structural Dynamics (CSD) methodology to perform a trimmed aeroelastic analysis of a rotor in forward flight. The coupling analyses, both loose and tight were used to identify the key physical phenomena that affect rotors in different steady flight regimes. The modeling enhancements improved the airloads predictions for a variety of flight conditions. It was found that the tightly coupled method did not impact the loads significantly for steady flight conditions compared to the loosely coupled method. The coupling methodology was extended to maneuvering flight analysis by enhancing the computational and structural models to handle non-periodic flight conditions and vehicle motions in time accurate mode. The flight test

  12. hydrolysis of certain nigeria:\\ cereal starches using crude fundal ...

    African Journals Online (AJOL)

    BSN

    E1gh: fi1amemous fungi \\\\ere isolated from garden soil. The mesophil ic isolates ... '>ugais produced from starches obtained from maize, sorghum and millet using the different ... can be convened to reducing sugars by either acid or enzymatic means ( 15). In most of ..... A. jlavus had the widest tolerance of pH in the ra'1ge ...

  13. 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..

  14. Pharyngeal Pressure Generation during Tongue-Hold Swallows across Age Groups

    Science.gov (United States)

    Doeltgen, Sebastian H.; Macrae, Phoebe; Huckabee, Maggie-Lee

    2011-01-01

    Purpose: To compare the effects of the tongue-hold swallowing maneuver on pharyngeal pressure generation in healthy young and elderly research volunteers. Method: Sixty-eight healthy research volunteers (young, n = 34, mean age = 26.8 years, SD = 5.5; elderly, n = 34, mean age = 72.6 years, SD = 4.8; sex equally represented) performed 5…

  15. Analysis of LFM-waveform Libraries for Cognitive Tracking Maneuvering Targets

    Directory of Open Access Journals (Sweden)

    Wang Hongyan

    2016-01-01

    Full Text Available Based on the idea of the waveform agility in cognitive radars,the waveform libraries for maneuvering target tracking are discussed. LFM-waveform libraries are designed according to different combinations of chirp parameters and FrFT rotation angles. By applying the interact multiple model (IMM algorithm in tracking maneuvering targets, transmitted waveform is called real time from the LFM-waveform libraries. The waveforms are selected from the library according to the criterion of maximum mutual information between the current state of knowledge of the model and the measurement. Simulation results show that waveform library containing certain amount LFM-waveforms can improve the performance of cognitive tracking radar.

  16. Design of a Robotic System to Measure Propulsion Work of Over-Ground Wheelchair Maneuvers.

    Science.gov (United States)

    Liles, Howard; Huang, Morris; Caspall, Jayme; Sprigle, Stephen

    2015-11-01

    A wheelchair-propelling robot has been developed to measure the efficiency of manual wheelchairs. The use of a robot has certain advantages compared to the use of human operators with respect to repeatability of measurements and the ability to compare many more wheelchair configurations than possible with human operators. Its design and implementation required significant engineering and validation of hardware and control systems. The robot can propel a wheelchair according to pre-programmed accelerations and velocities and measures the forces required to achieve these maneuvers. Wheel velocities were within 0.1 m/s of programmed values and coefficients of variation . Torque measurements were also repeatable with . By determining the propulsion torque required to propel the wheelchair through a series of canonical maneuvers, task-dependent input work for various wheelchairs and configurations can be compared. This metric would serve to quantify the combined inertial and frictional resistance of the mechanical system.

  17. Flight-Like Ground Demonstrations of Precision Maneuvers for Spacecraft Formations

    Science.gov (United States)

    Scharf, Daniel P.; Hadaegh, Fred Y.; Keim, Jason A.; Morfopoulos, Arin C.; Ahmed, Asif; Brenman, Yan; Vafaei, Ali; Shields, Joel F.; Bergh, Charles F.; Lawson, Peter R.

    2008-01-01

    Synchronized formation rotations are a common maneuver for planned precision formations. In such a rotation, attitudes remain synchronized with relative positions, as if the spacecraft were embedded in a virtual rigid body. Further, since synchronized rotations are needed for science data collection, this maneuver requires the highest precision control of formation positions and attitudes. A recently completed, major technology milestone for the Terrestrial Planet Finder Interferometer is the high-fidelity, ground demonstration of precision synchronized formation rotations. These demonstrations were performed in the Formation Control Testbed (FCT), which is a flight-like, multi-robot formation testbed. The FCT is briefly introduced, and then the synchronized rotation demonstration results are presented. An initial error budget consisting of formation simulations is used to show the connection between ground performance and TPF-I flight performance.

  18. Trajectory and Correction Maneuver During the Transfer from Earth to Halo Orbit

    Institute of Scientific and Technical Information of China (English)

    Xu Ming; Xu Shijie

    2008-01-01

    This article addresses the design of the trajectory transferring fi'om Earth to Halo orbit,and proposes a timing closed-loop strategy of correction maneuver during the trausfer in the frame of circular restricted three body problem (CR3BP).The relation between the Floquet multipliers and the magnitudes of Halo orbit is established,so that the suitable magnitude for the aerospace mission is chosen in previous researches,and six types of single-impulse transfer trajectories are attained from the geometry of the invariant manifolds.Based on one of the trajectories of indirect transfer which arc ignored in the most of literatures,the stochastic control theory for imperfect information of the discrete linear stochastic system is applied to design the trajectory correction maneuver.The statistical dispersion analysis is performed by Monte-Carlo simulation.

  19. A Vector Measurement-based Angular Velocity Estimation Scheme for Maneuvering Spacecraft

    Science.gov (United States)

    Jo, Sujang; Bang, Hyochoong; Leeghim, Henzeh

    2017-09-01

    A new practical approach to estimate the body angular velocity of maneuvering spacecraft using only vector measurements is presented. Several algorithms have been introduced in previous studies to estimate the angular velocity directly from vector measurements at two time instants. However, these direct methods are based on the constant angular velocity assumption, and estimation results may be invalid for attitude maneuvers. In this paper, an estimation scheme to consider attitude disturbances and control torques is proposed. The effects of angular velocity variation on estimation results are quantitatively evaluated, and an algorithm to minimize estimation errors is designed by selecting the optimal time interval between vector measurements. Without losing the simplicity of direct methods, the design parameters of the algorithm are restricted to the expected covariance of disturbances and the maximum angular acceleration. By applying the proposed estimation scheme, gyroscopes can be directly replaced by attitude sensors such as star trackers.

  20. Active control of tiltrotor blade in-plane loads during maneuvers

    Science.gov (United States)

    Miller, David G.; Ham, Norman D.

    1988-01-01

    The origin of one/rev rotor aerodynamic loads which arise in tiltrotor aircraft during airplane-mode high speed pull-up and push-over maneuvers is examined using a coupled rotor/fuselage dynamic simulation. A modified eigenstructure assignment technique is used to design a controller which alleviates the in-plane loads during high pitch rate maneuvers. The controller utilizes rotor cyclic pitch inputs to restructure the aircraft short period and phugoid responses in order to achieve the coupling between pitch rate and rotor flapping responses which minimizes the rotor aerodynamic loading. Realistic time delays in the feedback path are considered during the controller design. Stability robustness in the presence of high frequency modeling errors is ensured through the use of singular value analysis.

  1. Model predictive control of attitude maneuver of a geostationary flexible satellite based on genetic algorithm

    Science.gov (United States)

    TayyebTaher, M.; Esmaeilzadeh, S. Majid

    2017-07-01

    This article presents an application of Model Predictive Controller (MPC) to the attitude control of a geostationary flexible satellite. SIMO model has been used for the geostationary satellite, using the Lagrange equations. Flexibility is also included in the modelling equations. The state space equations are expressed in order to simplify the controller. Naturally there is no specific tuning rule to find the best parameters of an MPC controller which fits the desired controller. Being an intelligence method for optimizing problem, Genetic Algorithm has been used for optimizing the performance of MPC controller by tuning the controller parameter due to minimum rise time, settling time, overshoot of the target point of the flexible structure and its mode shape amplitudes to make large attitude maneuvers possible. The model included geosynchronous orbit environment and geostationary satellite parameters. The simulation results of the flexible satellite with attitude maneuver shows the efficiency of proposed optimization method in comparison with LQR optimal controller.

  2. An Iterative Learning Control Technique for Point-to-Point Maneuvers Applied on an Overhead Crane

    Directory of Open Access Journals (Sweden)

    Khaled A. Alhazza

    2014-01-01

    Full Text Available An iterative learning control (ILC strategy is proposed, and implemented on simple pendulum and double pendulum models of an overhead crane undergoing simultaneous traveling and hoisting maneuvers. The approach is based on generating shaped commands using the full nonlinear equations of motion combined with the iterative learning control, to use as acceleration commands to the jib of the crane. These acceleration commands are tuned to eliminate residual oscillations in rest-to-rest maneuvers. The performance of the proposed strategy is tested using an experimental scaled model of an overhead crane with hoisting. The shaped command is derived analytically and validated experimentally. Results obtained showed that the proposed ILC control strategy is capable of eliminating travel and residual oscillations in simple and double pendulum models with hoisting. It is also shown, in all cases, that the proposed approach has a low sensitivity to the initial cable lengths.

  3. A Novel Concept for Guidance and Control of Spacecraft Orbital Maneuvers

    Directory of Open Access Journals (Sweden)

    Matteo Dentis

    2016-01-01

    Full Text Available The purpose of this paper is the design of guidance and control algorithms for orbital space maneuvers. A 6-dof orbital simulator, based on Clohessy-Wiltshire-Hill equations, is developed in C language, considering cold gas reaction thrusters and reaction wheels as actuation system. The computational limitations of on-board computers are also included. A combination of guidance and control algorithms for an orbital maneuver is proposed: (i a suitably designed Zero-Effort-Miss/Zero-Effort-Velocity (ZEM/ZEV algorithm is adopted for the guidance and (ii a linear quadratic regulator (LQR is used for the attitude control. The proposed approach is verified for different cases, including external environment disturbances and errors on the actuation system.

  4. Virtual maneuvering test in CFD media in presence of free surface

    Directory of Open Access Journals (Sweden)

    Ahmad Hajivand

    2015-05-01

    Full Text Available Maneuvering oblique towing test is simulated in a Computational Fluid Dynamic (CFD environment to obtain the linear and nonlinear velocity dependent damping coefficients for a DTMB 5512 model ship. The simulations are carried out in freely accessible OpenFOAM library with three different solvers, rasInterFoam, LTSInterFoam and interDyMFoam, and two turbulence models, k-ε and SST k-ω in presence of free surface. Turning and zig-zag maneuvers are simulated for the DTMB 5512 model ship using the calculated damping coefficients with CFD. The comparison of simulated results with the available experimental shows a very good agreement among them.

  5. Effect of Wind to the Maneuvering Ship Control in the Avoidence Collision

    Directory of Open Access Journals (Sweden)

    Aulia S. Aisjah

    2012-11-01

    Full Text Available Marine transportation as an important roles in Indonesia, it is two third of Indonesian territorial is waters. Tanjung Perak port is one busiest transportation in Indonesia. To enter the terminal ship is shipping throuh Madura strait. To enhance ship safety management, navigational device known as AIS used for navigational purpose. AIS data contain multiple ship specification, statically and dynamically. Those data can be used as inputs in maneuvering control. This research focus on creating ship maneuvering control system by utilizing AIS data. The strategic control is Fuzzy Logic (FL. The aim of research is carrying ship to the trajectory to collision avoidence to other ship. The Fuzzy Logic Control consits two units: Heading control and speed control. The case study is applying controler to the cargo ship, and disturbance is wind in various coming angle.

  6. Purging using the Heimlich maneuver among children and adolescents with eating disorders.

    Science.gov (United States)

    Boachie, Ahmed; Kusi Appiah, Edigna; Jubin, Michelle; Jasper, Karin

    2015-09-01

    This case report describes five independent cases of children and adolescents assessed for eating disorders who disclosed using the Heimlich maneuver as a purging technique. The maneuver is meant to be used only in life or death situations, likely once or less in any person's lifetime. A child or adolescent with an eating disorder may be using it to self-induce vomiting on a daily basis, increasing the risk of complications, including potential damage to major organs of the body. Asking patients who purge to elaborate on the methods with which they purge can provide clinicians with fuller information, improving their ability to select appropriate medical tests and interventions. Thorough investigations of physical complaints during the patient assessment may be warranted, including examining patients for possible rib fractures, hemorrhages, perforations of the hollow viscous, and other forms of blunt abdominal traumas.

  7. Axial offset as measure of stability of light water nuclear reactor during capacity maneuvering

    Directory of Open Access Journals (Sweden)

    Mark V. Nikolsky

    2015-03-01

    Full Text Available High reliability and security of power unit are required during operation of power unit while maneuvering. They depend on the stability of reactor when transition from one power level to another. The axial offset is a quantitative measure of the reactor stability. It is shown that change of the active core inlet coolant temperature yields an uncontrollable disturbance affecting the axial offset and therefore the reactor stability. To insure the reactor stability the compromise-combined power control method is proposed. Analysis of the influence of temperature of coolant at the magnitude of the axial offset for different regulatory programs is carried out. The change in the depth of immersion of regulators in the active zone for different regulatory programs when the reactor plant daily capacity maneuver is studied.

  8. Implementation of the Orbital Maneuvering Systems Engine and Thrust Vector Control for the European Service Module

    Science.gov (United States)

    Millard, Jon

    2014-01-01

    The European Space Agency (ESA) has entered into a partnership with the National Aeronautics and Space Administration (NASA) to develop and provide the Service Module (SM) for the Orion Multipurpose Crew Vehicle (MPCV) Program. The European Service Module (ESM) will provide main engine thrust by utilizing the Space Shuttle Program Orbital Maneuvering System Engine (OMS-E). Thrust Vector Control (TVC) of the OMS-E will be provided by the Orbital Maneuvering System (OMS) TVC, also used during the Space Shuttle Program. NASA will be providing the OMS-E and OMS TVC to ESA as Government Furnished Equipment (GFE) to integrate into the ESM. This presentation will describe the OMS-E and OMS TVC and discuss the implementation of the hardware for the ESM.

  9. Hybrid Switching Controller Design for the Maneuvering and Transit of a Training Ship

    Directory of Open Access Journals (Sweden)

    Tomera Mirosław

    2017-03-01

    Full Text Available The paper presents the design of a hybrid controller used to control the movement of a ship in different operating modes, thereby improving the performance of basic maneuvers. This task requires integrating several operating modes, such as maneuvering the ship at low speeds, steering the ship at different speeds in the course or along the trajectory, and stopping the ship on the route. These modes are executed by five component controllers switched on and off by the supervisor depending on the type of operation performed. The desired route, containing the coordinates of waypoints and tasks performed along consecutive segments of the reference trajectory, is obtained by the supervisory system from the system operator. The former supports switching between component controllers and provides them with new set-points after each change in the reference trajectory segment, thereby ensuring stable operation of the entire hybrid switching controller.

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

    Science.gov (United States)

    2014-06-19

    McNish, “Latitude and Longitude,” RASC Calgary Centre, The Royal Astronomical Society of Canada, last modified 11 November 2011, accessed 17 August...maintains the prerogative of performing as many exo- or trans-atmospheric maneuvers as permitted by the ∆ capacity of the vehicle. Consequently, the...Wright-Patterson AFB, OH, March 2004 (ADA424074). McNish, Larry. “Latitude and Longitude.” RASC Calgary Centre, The Royal Astronomical Society

  11. Radon-Fractional Fourier Transform and Its Application to Radar Maneuvering Target Detection (Preprint)

    Science.gov (United States)

    2014-10-09

    Radon -Fractional Fourier Transform and Its Application to Radar Maneuvering Target Detection Xiaolong Chen*, Fuqing Cai, Yu Cong, Jian Guan...unit (ARU) and Doppler frequency migration (DFM) effects. In this paper, a novel transform called the Radon -fractional Fourier transform (RFRFT) is...are carried out and the performances of different methods including MTD, FRFT, and the Radon -Fourier transform (RFT) are compared, which demonstrate

  12. Transfer Maneuvers Between Periodic Earth-Moon Orbits Using Stable an Unstable Manifolds

    Science.gov (United States)

    Marcuzzi, J. P.; Leiva, A. M.; Briozzo, C. B.

    In this paper we have determined the stable and unstable manifold of six unstable periodic orbits (h=-1,586656) in an appropriate surface of section in the Earth-Moon coplanar circular restricted three body problem. The cost diagrams give account of a low transfer tax on using this technique and they would allow to determine the lower cost regions in order to apply the required propellent in each maneuver. FULL TEXT IN SPANISH

  13. Ecology of mule deer on the Pinon Canyon Maneuver Site, Colorado

    OpenAIRE

    Gerlach, Thomas P.

    1987-01-01

    Mule deer (Odocoileus hemionus) population dynamics, movements, and habitat use were studied on the Pinon Canyon Maneuver Site in southeastern Colorado during January 1983- December 1984. Thirty-eight adults and 28 fawns were radio collared, and 35 adults were color collared or ear tagged. Population estimates were 365 and 370 deer for 1983 and 1984, respectively. The sex ratio (yearling and adult) was 60 males: 100 females. Adult female pregnancy rate was 95%; the mean litter ...

  14. A New Approach to Satisfy Dynamic Similarity for Model Submarine Maneuvers

    Science.gov (United States)

    2007-11-28

    scale jam recovery, a steady approach speed is required for RCM correlation maneuvers. The scaled model approach speed must be set at 21 U.n0 . UsO (33...NAVSEA 05H Y M. King 1 ONR 331 Y R. Joslin 1 NSWCCD 3452 Y TIC (C) 1 NSWCCD 5060 Y D. Walden 1 NSWCCD 5080 Y J. Brown 1 NSWCCD 5080 Y B. Cox 1 NSWCCD 5400 Y

  15. A control strategy for steering an autonomous surface sailing vehicle in a tacking maneuver

    OpenAIRE

    2009-01-01

    Sailing vessels such as sailboats but also landyachts are vehicles representing a real challenge for automation. However, the control aspects of such vehicles were hitherto very little studied. This paper presents a simplied dynamic model of a so-called landyacht allowing to capture the main elements of the behavior of surface sailing vessels. We then propose a path generation scheme and a controller design for a well-known and fundamental maneuver in sailing referred to as tacking. Simulatio...

  16. Rapid maneuvering of multi-body dynamic systems with optimal motion compensation

    Science.gov (United States)

    Bishop, B.; Gargano, R.; Sears, A.; Karpenko, M.

    2015-12-01

    Rapid maneuvering of multi-body dynamical systems is an important, yet challenging, problem in many applications. Even in the case of rigid bodies, it can be difficult to maintain precise control over nominally stationary links if it is required to move some of the other links quickly because of the various nonlinearities and coupled interactions that occur between the bodies. Typical control concepts treat the multi-body motion control problem in two-stages. First, the nonlinear and coupling terms are treated as disturbances and a trajectory tracking control law is designed in order to attenuate their effects. Next, motion profiles are designed, based on kinematics parameterizations, and these are used as inputs to the closed loop system to move the links. This paper describes an approach for rapid maneuvering of multi-body systems that uses optimal control theory to account for dynamic nonlinearities and coupling as part of the motion trajectory design. Incorporating appropriate operational constraints automatically compensates for these multi-body effects so that motion time can be reduced while simultaneously achieving other objectives such as reducing the excitation of selected links. Since the compensatory effect is embedded within the optimal motion trajectories, the performance improvement can be obtained even when using simple closed-loop architectures for maneuver implementation. Simulation results for minimum time control of a two-axis gimbal system and for rapid maneuvering of a TDRS single-access antenna, wherein it is desired to limit the excitation of the satellite body to which the antenna is attached, are presented to illustrate the concepts.

  17. Operational Maneuver From the Sea: Reducing the Need for Battlespace Dominance in the Littoral Regions.

    Science.gov (United States)

    2007-11-02

    to conduct a joint "operational maneuver from the sea and air." The Integrated Battle Organization ( IBO ) is a new C2 concept, developed by the Naval... IBO has a flat, vice hierarchical, organizational structure.43 It resembles and meshes nicely with the JTF C2 structure. Although still under...development and evaluation, the IBO is a huge step in the right direction. In order for OMFTS to work more effectively in a joint arena, a standard flexible

  18. A Systems Engineering Approach in Providing Air Defense Support to Ground Combat Vehicle Maneuver Forces

    Science.gov (United States)

    2015-03-01

    http://www.strategypage.com/dls/ articles /SLAMRAAM-Dies-From-Loneliness-2- 5-2011.asp. Federation of American Scientists . 2000. “M6 Bradley Linebacker...MANPADS-under-armor (MUA) concept was adopted to provide mobile air defense to maneuver forces (Federation of American Scientists 2000). This involved... swim in water. The functional hierarchy for the Move function is shown in Figure 17. 39 Figure 17. Functional Hierarchy for F.3 Move d

  19. Bearings-only fusion tracking for maneuvering target with wavelet transform in three dimensional space

    Institute of Scientific and Technical Information of China (English)

    Tian Hongwei; Jing Zhongliang; Hu Shiqiang; Li Jianxun

    2005-01-01

    A new fusion tracking algorithm is presented to track maneuvering target in three-dimensional (3D) space with bearings-only measurements. With the introduction of passive location and interacting multiple model (IMM) algorithm based on multirate model, the high-rate sequence measurements of two sensors are utilized. Simulation results show that the performance of tracking has been improved. The new algorithm removes the barrier of processing high-rate bearingsonly measurements.

  20. The role of the thoracic compression reflex in the Heimlich Maneuver.

    Science.gov (United States)

    Crawford, L M; Emmett, J W

    1977-01-01

    Using the dog as an experimental model, the relationship of the Thoracic Compression Reflex (TCR) to the Heimlich Maneuver (HM) was examined. TCR was equally effective as lateral chest compression in relieving artificially induced choke. Destruction of the TCR by vagotomy rendered relief of choke by HM ineffectual in 5 of 8 dogs. It was concluded TCR may be a factor in HM, but that mechanical compression of the lungs is also involved.

  1. An Expedite Approximate Algorithm for Calculating the Controls in the Longitudinal Maneuver

    OpenAIRE

    Laurentiu MORARU

    2015-01-01

    This paper discusses an expedite approximate algorithm for obtaining the controls in the longitudinal maneuver of the aerospace vehicles. The equations of motion are written in terms of the flight path (the trajectory that is desired is also given in terms of flight path, that is the local radius of curvature is given as a function of flight path) and the controls required for following a desired trajectory obtained accordingly. A finite terms integration procedure is subsequently presented.

  2. Safe Certificate-Based Maneuvers for Teams of Quadrotors Using Differential Flatness

    OpenAIRE

    Wang, Li; Ames, Aaron D.; Egerstedt, Magnus

    2017-01-01

    Safety Barrier Certificates that ensure collision-free maneuvers for teams of differential flatness-based quadrotors are presented in this paper. Synthesized with control barrier functions, the certificates are used to modify the nominal trajectory in a minimally invasive way to avoid collisions. The proposed collision avoidance strategy complements existing flight control and planning algorithms by providing trajectory modifications with provable safety guarantees. The effectiveness of this ...

  3. Literature concerning control and display technology applicable to the Orbital Maneuvering Vehicle (OMV)

    Science.gov (United States)

    1990-01-01

    A review is presented of the literature concerning control and display technology that is applicable to the Orbital Maneuvering Vehicle (OMV), a system being developed by NASA that will enable the user to remotely pilot it during a mission in space. In addition to the general review, special consideration is given to virtual image displays and their potential for use in the system, and a preliminary partial task analysis of the user's functions is also presented.

  4. Tracking the Turn Maneuvering Target Using the Multi-Target Bayes Filter with an Adaptive Estimation of Turn Rate.

    Science.gov (United States)

    Liu, Zong-Xiang; Wu, De-Hui; Xie, Wei-Xin; Li, Liang-Qun

    2017-02-15

    Tracking the target that maneuvers at a variable turn rate is a challenging problem. The traditional solution for this problem is the use of the switching multiple models technique, which includes several dynamic models with different turn rates for matching the motion mode of the target at each point in time. However, the actual motion mode of a target at any time may be different from all of the dynamic models, because these models are usually limited. To address this problem, we establish a formula for estimating the turn rate of a maneuvering target. By applying the estimation method of the turn rate to the multi-target Bayes (MB) filter, we develop a MB filter with an adaptive estimation of the turn rate, in order to track multiple maneuvering targets. Simulation results indicate that the MB filter with an adaptive estimation of the turn rate, is better than the existing filter at tracking the target that maneuvers at a variable turn rate.

  5. Auditory stimulation with music influences the geometric indices of heart rate variability in response to the postural change maneuver

    National Research Council Canada - National Science Library

    Bianca C R de Castro; Heraldo L Guida; Adriano L Roque; Luiz Carlos de Abreu; Celso Ferreira; Renata S Marcomini; Carlos B M Monteiro; Fernando Adami; Viviane F Ribeiro; Fernando L A Fonseca; Vilma N S Santos; Vitor E Valenti

    2014-01-01

    ...) during the musical auditory stimulation. The objective is to investigate the acute effects of classic musical auditory stimulation on the geometric indexes of HRV in women in response to the postural change maneuver (PCM...

  6. Persistent Direction-Fixed Nystagmus Following Canalith Repositioning Maneuver for Horizontal Canal BPPV: A Case of Canalith Jam.

    Science.gov (United States)

    Chang, Young-Soo; Choi, Jeesun; Chung, Won-Ho

    2014-06-01

    The authors report a 64-year-old man who developed persistent direction fixed nystagmus after a canalith repositioning maneuver for horizontal canal benign paroxysmal positional vertigo (HC-BPPV). The patient was initially diagnosed with right HC-BPPV given that the Dix-Hallpike test showed geotropic horizontal nystagmus that was more pronounced on the right side, although the roll test did not show any positional nystagmus. The patient was treated with a canalith repositioning maneuver (Lempert maneuver). The next day, the patient experienced a different character of dizziness, and left-beating spontaneous nystagmus regardless of head position was observed. After a forced prolonged left decubitus and frequent head shaking, his symptoms and nystagmus resolved. This condition, referred to as canalith jam, can be a complication after the repositioning maneuver in patients with BPPV. Atypical positional tests suggest that abnormal canal anatomy could be the underlying cause of canalith jam.

  7. The effect of initial velocity on manually controlled remote docking of an orbital maneuvering vehicle (OMV) to a space station

    Science.gov (United States)

    Brody, Adam R.

    1989-01-01

    Simulated docking maneuvers were performed to assess the effect of initial velocity on docking failure rate, mission duration, and total impulse (fuel consumption). The effect of the removal of the range and rate displays was also examined. Since duration and impulse decrease and increase respectively with increases in initial velocity, two parameters were created by subtracting a reference value from each. These values were termed 'reserve time' and 'radial impulse'. Naive subjects were capable of achieving a high success rate in performing simulated docking maneuvers without extensive experience, and failure rate did not significantly increase with increased velocity. The amount of time pilots reserved for final approach increased with starting velocity. Piloting of docking maneuvers was not significantly affected in any way by the removal of range and rate displays. Values for reserve time, and radial impulse were lowest for docking maneuvers begun at the lowest initial velocity.

  8. Roll maneuvering of flexible aircraft with distributed-parameter actuation via modal synthesis

    Science.gov (United States)

    Oz, Hayrani; Khot, Narendra S.

    1999-06-01

    The focus is on obtaining and identifying optimal distributed- parameter-control equivalent actuation profiles for desired roll maneuvers by a modal synthesis approach. The solution for distributed-parameter-control of an aeroelastic system is developed by synthesis of modal-state-space controllers designed via the globally power optimal Independent Modal- Space Control (IMSC) technique. The desired maneuver (set- point) control performance is achieved by a modal-performance- output synthesis (MPOS) approach. The MPOS approach requires that each independent modal controller be allocated a desired portion of the total desired output performance. In view of this, a modal performance-output allocation optimization problem is also defined, which minimizes a hybrid measure of control power and elastic strain energy of the structure during aeroelastic control. Insight to distributed-parameter- control equivalent actuation solutions are sought by considering the aeroservoelastic interactions among vehicle motion, aerodynamics, structural flexibility and control actuators from the perspective of work-energy, control power, and control loading requirements. The modal synthesis approach is illustrated for a flight vehicle wing design to achieve a 90 deg/sec roll-rate in a Mach 2 flight condition at altitude (20000 ft) via distributed-parameter equivalent actuation. The preliminary results indicate that such a roll-rate maneuver can be accomplished via distributed-parameter actuation with feasible levels of control power, work-energy, and control loadings through eliciting favorable aeroservoelastic interactions.

  9. Dynamic Modeling and Investigation of Maneuver Characteristics of A Deep-Sea Manned Submarine Vehicle

    Institute of Scientific and Technical Information of China (English)

    XIE Jun-yuan; XU Wen-bo; ZHANG Hua; XU Peng-fei; CUI Wei-cheng

    2009-01-01

    A deep-sea Manned Submarine Vehicle (MSV) is usually required to move at a low forward speed and a low rota- tional speed when it executes investigation tasks. In this condition, the motion is in large drift angles, and the maneuver- ability hydrodynamic forces cannot be expressed properly in the conventional mathematical model of submersible motion. In this paper, firstly, a general equation of MSV with six-freedom motion is presented, and the numerical simulation of descent/ascent motion and helix motion is conducted to reveal the general maneuver characteristics of MSV. Secondly, according to the data of captive model tests of large drift angles of MSV, the regression analysis of position hydrodynamic forces and rotation hydrodynamic forces is carried out, and the resuhs of regression analysis of maneuverabihty hydrody-namic characteristics are analyzed to reveal the special maneuver characteristics. Thirdly, a special new mathematical model of MSV with the whole range of drift angles motion is presented, which can be used to predict hydrodynamic per-formance of motion in the 0°~180° range of drift angles. The resuhs are applied to the design of maneuverability hydro- dynamic forces, development of control system and simulator of a practical MSV.

  10. Real Time Mid-course Maneuver and Guidance of a Generic Reentry Vehicle

    Directory of Open Access Journals (Sweden)

    Avinash Chander

    2013-07-01

    Full Text Available The aim of any mission is to accomplish the final objective with desired accuracy and the same is valid for a generic launch vehicle. In many missions it is necessary to execute mid-course maneuvers with an intentional diversion trajectory to create a counter measure or to avoid certain specific known geographical locations. The current work elaborates a novel and practically implementable mid-course maneuver and an ascent phase guidance of a reentry vehicle executing an in-flight determined mid-course maneuver (trajectory reshaping without compromising the accuracy of the final achieved target position. The robustness of the algorithm is validated with 6DoF simulation results by considering the dispersion of the burnout state vector conditions which arises due to variations in thrust profile, aerodynamics characteristics of the vehicle, atmosphere, etc.Defence Science Journal, 2013, 63(4, pp.346-354, DOI:http://dx.doi.org/10.14429/dsj.63.4207

  11. Reducing Pointing Errors During Cassini Reaction Control System Orbit Trim Maneuvers

    Science.gov (United States)

    Rizvi, Farheen

    2013-01-01

    The effect of altering a gain parameter in the Cassini reaction control system (RCS) delta-V controller on the maneuver execution errors during orbit trim maneuvers (OTMs) is explored. Cassini consists of two reaction control thruster branches (A & B) each with eight thrusters. Currently, the B-branch is operational while the A-branch serves as a back-up. The four Z-thrusters control the X and Y-axes, while the four Y-thrusters control the Z-axis. During an OTM, the Z-thrusters fire to maintain the X and Y-axes pointing within an attitude control dead-zone (-10 to 10 milliradians). The errors do not remain at zero due to pointing error sources such as spacecraft center of mass offset from the geometric center of the Z-facing thrusters, and variability in the thruster forces due to the thruster hardware differences. The delta-V reaction control system (RCS) controller ensures that the attitude error remains within this dead-zone. Gain parameters within the RCS delta-V controller affect the maneuver execution errors. Different parameter values are used to explore effect on these errors. It is found that pointing error decreases and magnitude error increases rapidly for gain parameters 10 times greater than the current parameter values used in the flight software.

  12. Attitude maneuver of liquid-filled spacecraft with a flexible appendage by momentum wheel

    Institute of Scientific and Technical Information of China (English)

    Dan-Dan Yang; Bao-Zeng Yue; Wen-Jun Wu; Xiao-Juan Song; Le-Mei Zhu

    2012-01-01

    Attitude maneuver of liquid-filled spacecraft with an appendage as a cantilever beam by momentum wheel is studied.The dynamic equations are derived by conservation of angular momentum and force equilibrium principle.A feedback control strategy of the momentum wheel is applied for the attitude maneuver.The residual nutation of the spacecraft in maneuver process changes with some chosen parameters,such as steady state time,locations of the liquid container and the appendage,and appendage parameters.The results indicate that locations in the second and fourth quadrants of the body-fixed coordinate system and the second quadrant of the wall of the main body are better choices forplacing the liquid containers and the appendage than other locations if they can be placed randomly.Higher density and thicker cross section are better for lowering the residual nutation if they can be changed.Light appendage can be modeled as a rigid body,which results in a larger residual nutation than a flexible model though.The residual nutation decreases with increasing absolute value of the initial sloshing angular height.

  13. Detection, parameter estimation and imaging of maneuvering target in wide-band signal

    Institute of Scientific and Technical Information of China (English)

    LI YaChao; XING MengDao; ZHANG Long; BAO Zheng

    2009-01-01

    The signal-to-noise ratio may be increased by the cross-range coherence integration so as to detect the moving target in low signal-to-noise ratio (SNR) condition. But, the radial velocity, acceleration and the change of acceleration due to the maneuvering motion of target may induce serious range migration and crose-range high-order phase terms leading to the unfocused cross-range image, the reduction of signal-noise ratio and the invalidation of target detection. Therefore, in order to solve these problems,this paper proposes a new method based on the adjacent correlation and scale transform methods for detection, parameters estimation and imaging of maneuvering targets in wide-band signal. This method can align the range and remove the cross-range high-order phase terms induced by the radial motion of target, enabling us to detect the target and estimate its moving parameters better. Finally, the simulated target is used to confirm that the method proposed by this paper can perfectly detect the maneuvering target in low signal-to-noise ratio condition, estimate its motion parameters and obtain an ISAR image of target.

  14. Anatomical study of the effects of five surgical maneuvers on palate movement.

    Science.gov (United States)

    Mendonca, Derick A; Patel, Kamlesh B; Skolnick, Gary B; Woo, Albert S

    2014-06-01

    The anatomy of the palate has been extensively described, with a predominant focus on palatal musculature. There are no biomechanical studies investigating the effects of surgical maneuvers on the palate to aid cleft closure. This study aims to describe the soft tissue attachments at different zones and quantify the movement following their release. Fourteen adult cadaver heads were dissected. The palates were split in the midline and five maneuvers described: Step 1, over the hard palate; Step 2, around the greater palatine pedicle; Step 3, over the palatine aponeurosis; Step 4, over the hamulus; and Step 5, resulting in a hamulus fracture. The movements across the midline at the posterior nasal spine following each maneuver were measured. The age range of the 14 heads was between 60 -75 years. Completion of steps 1 and 2 over the hard palate obtained a mean release of 2.6 and 2.0 mm, respectively. The largest movements occurred at Step 3 (5.7 mm) and Step 4 (3.5 mm), after releasing attachments at the posterior hard palate and palatine aponeurosis. Steps 3 and 4 dissections exhibited cumulative release, with a maximum movement with Step 3 (p palate junction. Additional dissection along the hamulus (without fracture) added significantly to this release.

  15. Fundamental Study of Evaluation at Berthing Training for Pilot Trainees Using a Ship Maneuvering Simulator

    Directory of Open Access Journals (Sweden)

    Kazuki Inoue

    2013-03-01

    Full Text Available Use of the ship maneuvering simulator (SMS is at the core of pilot trainees education and training, so it is desirable to have an evaluation method that can be completed shortly after each berthing training session. There are basically two methods of docking maneuvering that pilot trainees learn: one in which the ship enters from outside the port and is berthed directly at the target quay, and a second method in which the vessel carries out a turn in front of the target quay before berthing. The authors suggested an evaluation index in a previous study concerning the first docking method. In the present study, the authors propose an evaluation method for the case of berthing the vessel using the turning maneuver. Since the index obtained by this method offers a single numerical benchmark, it is an easy–to-understand result of the training exercise. The authors carried out experiments using a SMS and confirmed that the proposed evaluation method is effective and helpful to improve the effectiveness of SMS training.

  16. Prediction of Ship Unsteady Maneuvering in Calm Water by a Fully Nonlinear Ship Motion Model

    Directory of Open Access Journals (Sweden)

    Ray-Qing Lin

    2012-01-01

    Full Text Available This is the continuation of our research on development of a fully nonlinear, dynamically consistent, numerical ship motion model (DiSSEL. In this study we will report our results in predicting ship motions in unsteady maneuvering in calm water. During the unsteady maneuvering, both the rudder angle, and ship forward speed vary with time. Therefore, not only surge, sway, and yaw motions occur, but roll, pitch and heave motions will also occur even in calm water as heel, trim, and sinkage, respectively. When the rudder angles and ship forward speed vary rapidly with time, the six degrees-of-freedom ship motions and their interactions become strong. To accurately predict the six degrees-of-freedom ship motions in unsteady maneuvering, a universal method for arbitrary ship hull requires physics-based fully-nonlinear models for ship motion and for rudder forces and moments. The numerical simulations will be benchmarked by experimental data of the Pre-Contract DDG51 design and an Experimental Hull Form. The benchmarking shows a good agreement between numerical simulations by the enhancement DiSSEL and experimental data. No empirical parameterization is used, except for the influence of the propeller slipstream on the rudder, which is included using a flow acceleration factor.

  17. Breathing Maneuvers as a Vasoactive Stimulus for Detecting Inducible Myocardial Ischemia – An Experimental Cardiovascular Magnetic Resonance Study

    Science.gov (United States)

    Fischer, Kady; Guensch, Dominik P; Shie, Nancy; Lebel, Julie; Friedrich, Matthias G

    2016-01-01

    Background Breathing maneuvers can elicit a similar vascular response as vasodilatory agents like adenosine; yet, their potential diagnostic utility in the presence of coronary artery stenosis is unknown. The objective of the study is to investigate if breathing maneuvers can non-invasively detect inducible ischemia in an experimental animal model when the myocardium is imaged with oxygenation-sensitive cardiovascular magnetic resonance (OS-CMR). Methods and Findings In 11 anesthetised swine with experimentally induced significant stenosis (fractional flow reserve coronary artery (LAD) and 9 control animals, OS-CMR at 3T was performed during two different breathing maneuvers, a long breath-hold; and a combined maneuver of 60s of hyperventilation followed by a long breath-hold. The resulting change of myocardial oxygenation was compared to the invasive measurements of coronary blood flow, blood gases, and oxygen extraction. In control animals, all breathing maneuvers could significantly alter coronary blood flow as hyperventilation decreased coronary blood flow by 34±23%. A long breath-hold alone led to an increase of 97±88%, while the increase was 346±327% (pcoronary blood flow response was attenuated after both hyperventilation and the following breath-hold. This was matched by the observed oxygenation response as breath-holds following hyperventilation consistently yielded a significant difference in the signal of the MRI images between the perfusion territory of the stenosis LAD and remote myocardium. There was no difference between the coronary territories during the other breathing maneuvers or in the control group at any point. Conclusion In an experimental animal model, the response to a combined breathing maneuver of hyperventilation with subsequent breath-holding is blunted in myocardium subject to significant coronary artery stenosis. This maneuver may allow for detecting severe coronary artery stenosis and have a significant clinical potential as a

  18. Hemodynamic responses during and after multiple sets of stretching exercises performed with and without the Valsalva maneuver

    OpenAIRE

    Lima,Tainah P.; Paulo T.V. Farinatti; Ercole C. Rubini; Silva, Elirez B.; Monteiro, Walace D.

    2015-01-01

    OBJECTIVE: This study investigated the acute hemodynamic responses to multiple sets of passive stretching exercises performed with and without the Valsalva maneuver. METHODS: Fifteen healthy men aged 21 to 29 years with poor flexibility performed stretching protocols comprising 10 sets of maximal passive unilateral hip flexion, sustained for 30 seconds with equal intervals between sets. Protocols without and with the Valsalva maneuver were applied in a random counterbalanced order, separated ...

  19. Incomplete swallowing and retracted tongue maneuvers for electromyographic signal normalization of the extrinsic muscles of the larynx.

    Science.gov (United States)

    Balata, Patricia Maria Mendes; Silva, Hilton J; Nascimento, Gerlane Karla O; Moraes, Klyvia Juliana R; Pernambuco, Leandro A; Freitas, Maria Clara R; Lima, Leilane M; Braga, Renata S; Souza, Síntia R; Moraes, Silvia Regina A

    2012-11-01

    To investigate which muscular maneuvers provide larger electric activity (EA) of the suprahyoid (SH) and infrahyoid (IH) muscles to be used as surface electromyography (SEMG) signal normalization reference. The electrical potentials of the SH and IH muscles of 12 subjects were evaluated using six muscular maneuvers, involving the position of the tongue and effort. It was selected as maximum voluntary sustained activity maneuver, the one having the minor coefficient of variation and the smallest value for each muscle group. The EA signal was converted using the root mean square in microvolts. It was considered then the maximum signal of each maneuver as the difference between the mean of three measures and the resting potential. The maneuvers that provided higher mean potentials with minor coefficient of variation and smallest P value were incomplete swallowing (IS) with effort (mean potential equal to 56.73±8.68 with coefficient of variation of 15.30%) in SH group, and tongue retracted with mouth open (TROM, mean potential equal to 46.57±7.83 with coefficient of variation of 16.81%) in IH group. The IS with effort and TROM maneuvers should be considered for signal normalization in these muscles, respectively, and may provide conditions for using the SEMG in voice clinic. The use of normalization standards in researches of SH and IH muscles in the voice area will allow comparisons among future works. Copyright © 2012 The Voice Foundation. Published by Mosby, Inc. All rights reserved.

  20. Maintaining Aura's Orbit Requirements While Performing Orbit Maintenance Maneuvers Containing an Orbit Normal Delta-V Component

    Science.gov (United States)

    Johnson, Megan R.; Petersen, Jeremy D.

    2014-01-01

    The Earth Observing System (EOS) Afternoon Constellation consists of five member missions (GCOM-W1, Aqua, CALIPSO, CloudSat, and Aura), each of which maintain a frozen, sun-synchronous orbit with a 16-day repeating ground track that follows the Worldwide Reference System-2 (WRS-2). Under nominal science operations for Aura, the propulsion system is oriented such that the resultant thrust vector is aligned 13.493 degrees away from the velocity vector along the yaw axis. When performing orbit maintenance maneuvers, the spacecraft performs a yaw slew to align the thrust vector in the appropriate direction. A new Drag Make Up (DMU) maneuver operations scheme has been implemented for Aura alleviating the need for the 13.493 degree yaw slew. The focus of this investigation is to assess the impact that no-slew DMU maneuver operations will have on Aura's Mean Local Time (MLT) which drives the required along track separation between Aura and the constellation members, as well as Aura's frozen orbit properties, eccentricity and argument of perigee. Seven maneuver strategies were analyzed to determine the best operational approach. A mirror pole strategy, with maneuvers alternating at the North and South poles, was implemented operationally to minimize impact to the MLT. Additional analysis determined that the mirror pole strategy could be further modified to include frozen orbit maneuvers and thus maintain both MLT and the frozen orbit properties under noslew operations.

  1. Predictors of the Cardiodepressive Effect of Alveolar Opening Maneuver (Mobilization in Cardiosurgical Patients

    Directory of Open Access Journals (Sweden)

    A. A. Romanov

    2010-01-01

    Full Text Available Objective: to reveal the predictors of clinically significant deterioration of cardiac pump function resulting from alveolar opening maneuver (AOM (mobilization made early after extracorporeal circulation during standard cardiosurgery. Subjects and methods. Hemodynamic, clinical, and laboratory parameters were analyzed in 20 cardiosurgical patients who had undergone AOM in the early postperfusion period. The study inclusion criteria were a PaO2/FiO2 ratio of less than 350 mm Hg, a cardiac index (CI of more than 2.5 l/min/m2, a dosage of dopamine and/or dobutamine of not more than 10 μg/kg/min, and standard AOM performance (Pmax, 30—35 cm H2O; endexpiratory pressure (PEEP, 13—15 cm H2O. Regression analysis was used to identify the predictors of a clinically significant reduction in CI (less than 2.5 l/min/m2. Results. Before and after AOM, CI was 3.1±0.1 and 2.9±0.1 l/min/m2, respectively (p>0.05; however, CI was less than 2.5 l/min/m2 (2.16±0.09 l/min/m2 in 25% of cases. After AOM, CI values were significantly related to those recorded prior to a respiratory procedure (p=0.039, total peripheral vascular resistance index (TPVRI (p=0.00039, and intrapulmonary blood shunt fraction (Qs/Qt (p=0.041. There were no relationships to other recorded and estimated hemodynamic parameters (p>0.1. After AOM, CI values were unrelated (p>0.1 to the duration of extracorporeal circulation, the period of myocardial ischemia, and the used dosages of inotropic agents. The predictor of a clinically significant CI reduction after AOM was the only index TPVRI (p=0.00025 recorded before a respiratory procedure. Following AOM, the probability of a significant CI reduction substantially increased (the approximation coefficient R2=0.75 at TPVRI values of 2000 din•sec•cm-5•m2 or more. Conclusion. After AOM performed in the early period after extracorporeal circulation, CI values are related to the baseline level of CI, TPVRI, and Qs/Qt; however, after this

  2. Positive expiratory pressure and oscillatory positive expiratory pressure therapies.

    Science.gov (United States)

    Myers, Timothy R

    2007-10-01

    Airway clearance techniques, historically referred to as chest physical therapy, have traditionally consisted of a variety of breathing maneuvers or exercises and manual percussion and postural drainage. The methods and types of airway clearance techniques and devices have rapidly increased in an effort to find a more efficacious strategy that allows for self-therapy, better patient adherence and compliance, and more efficient durations of care. Mechanically applied pressure devices have migrated from European countries over the last several decades to clinical practice in the United States. I conducted a comprehensive MEDLINE search of two such devices: positive expiratory pressure (PEP) and oscillatory positive expiratory pressure (OPEP) and their role in airway clearance strategies. This was followed by a comprehensive search for cross-references in an attempt to identify additional studies. The results of that search are contained and reported in this review. From a methods standpoint, most of the studies of PEP and OPEP for airway clearance are limited by crossover designs and small sample sizes. While PEP and OPEP do not definitively prove superiority to other methods of airway clearance strategies, there is no clear evidence that they are inferior. Ultimately, the correct choice may be an airway clearance strategy that is clinically and cost effective, and is preferred by the patient so that adherence and compliance can be at the very least supported.

  3. Uncertainty Requirement Analysis for the Orbit, Attitude, and Burn Performance of the 1st Lunar Orbit Insertion Maneuver

    Science.gov (United States)

    Song, Young-Joo; Bae, Jonghee; Kim, Young-Rok; Kim, Bang-Yeop

    2016-12-01

    In this study, the uncertainty requirements for orbit, attitude, and burn performance were estimated and analyzed for the execution of the 1st lunar orbit insertion (LOI) maneuver of the Korea Pathfinder Lunar Orbiter (KPLO) mission. During the early design phase of the system, associate analysis is an essential design factor as the 1st LOI maneuver is the largest burn that utilizes the onboard propulsion system; the success of the lunar capture is directly affected by the performance achieved. For the analysis, the spacecraft is assumed to have already approached the periselene with a hyperbolic arrival trajectory around the moon. In addition, diverse arrival conditions and mission constraints were considered, such as varying periselene approach velocity, altitude, and orbital period of the capture orbit after execution of the 1st LOI maneuver. The current analysis assumed an impulsive LOI maneuver, and two-body equations of motion were adapted to simplify the problem for a preliminary analysis. Monte Carlo simulations were performed for the statistical analysis to analyze diverse uncertainties that might arise at the moment when the maneuver is executed. As a result, three major requirements were analyzed and estimated for the early design phase. First, the minimum requirements were estimated for the burn performance to be captured around the moon. Second, the requirements for orbit, attitude, and maneuver burn performances were simultaneously estimated and analyzed to maintain the 1st elliptical orbit achieved around the moon within the specified orbital period. Finally, the dispersion requirements on the B-plane aiming at target points to meet the target insertion goal were analyzed and can be utilized as reference target guidelines for a mid-course correction (MCC) maneuver during the transfer. More detailed system requirements for the KPLO mission, particularly for the spacecraft bus itself and for the flight dynamics subsystem at the ground control center

  4. Application of CO2 waveform in the alveolar recruitment maneuvers of hypoxemic patients during one-lung ventilation.

    Science.gov (United States)

    Dong, Chunshan; Yu, Junma; Liu, Qi; Wu, Chao; Lu, Yao

    2016-06-01

    Deterioration of gas exchange during one-lung ventilation (OLV) is caused by both total collapse of the nondependent lung and partial collapse of the dependent lung. Alveolar recruitment maneuver improves lung function during general anesthesia. The objective of this study was to investigate whether there is an indirect relationship between the changes of CO2 expirogram and the selective lung recruitment. To further improve the oxygenation and gas exchange, we compare adjust setting of ventilated parameters based on CO2 expirogram and a preset setting of ventilated parameters during OLV in patients undergoing right-side thoracic surgery.Thirty patients met the requirements criteria that were studied at 3 time points: during two-lung ventilation (TLV), during OLV with preset ventilation parameters (OLV-PP), and during OLV with adjustable ventilation parameters (OLV-AP) that are in accordance with CO2 expirogram. Adjustable ventilation parameters such as tidal volume (VT), respiratory rate (RR), positive end-expiratory pressure (PEEP), and the ratio of inspiratory to expiratory were adjusted by utilizing the phase III slopes of CO2 expirogram, which together with the relationship between the changes of CO2 expirogram and the selective lung recruitment.During OLV, the phase III slopes of CO2 expirogram in patients with pulse oxymetry (SpO2) decreased less than 93% after the OLV-PP, and were absolutely different from that during TLV. After OLV-AP, the phase III slopes of CO2 expirogram and SpO2 were similar to those during TLV. During OLV, however, parameters of ventilation setting in both OLV-PP and OLV-AP are obviously different.This study indicates that alveolar recruitment by utilizing CO2 expirogram probably improves SpO2 level during one-lung ventilation.

  5. The Evolution of Air-Sea Battle: How Army Attack/Reconnaissance Aviation Fits into the Joint Concept for Access and Maneuver in the Global Commons

    Science.gov (United States)

    2016-05-13

    Aviat 5a. CONTRACT NUMBER Aviation Fits into the Joint Concept for Access and Maneuver in the Global Commons 5b. GRANT NUMBER...The evolution of the Air-Sea Battle concept into the Joint Concept for Access and Maneuver in the Global Commons (JAM-GC) provides an opportunity...Aviation into JAM-GC to achieve better cross-domain synergy. 15. SUBJECT TERMS Joint Concept for Access and Maneuver in the Global Commons , JAM-GC

  6. Pressure ulcers

    National Research Council Canada - National Science Library

    Reddy, Madhuri

    2011-01-01

    Unrelieved pressure or friction of the skin, particularly over bony prominences, can lead to pressure ulcers in up to one third of people in hospitals or community care, and one fifth of nursing home residents...

  7. Pressure Sores

    Science.gov (United States)

    Pressure sores are areas of damaged skin caused by staying in one position for too long. They ... wheelchair, or are unable to change your position. Pressure sores can cause serious infections, some of which ...

  8. Positive expiratory pressure and oscillatory positive expiratory pressure therapies

    National Research Council Canada - National Science Library

    Myers, Timothy R

    2007-01-01

    Airway clearance techniques, historically referred to as chest physical therapy, have traditionally consisted of a variety of breathing maneuvers or exercises and manual percussion and postural drainage...

  9. Kinematics and shoulder belt position of child rear seat passengers during vehicle maneuvers.

    Science.gov (United States)

    Bohman, Katarina; Stockman, Isabelle; Jakobsson, Lotta; Osvalder, Anna-Lisa; Bostrom, Ola; Arbogast, Kristy B

    2011-01-01

    Head impact to the seat back has been identified as one important injury causation scenario for seat belt restrained, head-injured children and previous research highlighted vehicle maneuvers prior to impact as possible contributing factors. The aim was to quantify kinematics of child occupants during swerving maneuvers focusing on the child's lateral movement and seat belt position relative to the child's shoulder. A study was conducted on a closed-circuit test track with 16 children aged 4-12, restrained in the rear seat of a modern passenger vehicle. A professional driving instructor drove at 50 km/h making sharp turns in a repeatable fashion, resulting in inboard motion of the children. The children were exposed to two turns in each of two restraint systems. Shorter children were on a booster or highback booster cushion. The taller children were seated on a booster cushion or with only a lap and shoulder seat belt. Four film cameras were fixed in the vehicle monitoring the child. Vehicle data were also collected. The seat belt slipped off the shoulder in 1 of 5 turns, varying by age and restraint type. Among shorter children, the belt slipped off in a majority of turns when seated on a booster cushion while the belt remained on the shoulder when seated on the highback booster cushion. Among taller children, the shoulder belt moved far laterally on the shoulder in half of the turns. This data provides valuable knowledge on possible pre-impact postures of children as a result of vehicle swerving maneuvers for a variety of restraint systems.

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

    Science.gov (United States)

    Kress, Daniel; van Bokhorst, 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 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.

  11. Psychophysiological Assessment in Pilots Performing Challenging Simulated and Real Flight Maneuvers.

    Science.gov (United States)

    Johannes, Bernd; Rothe, Stefanie; Gens, André; Westphal, Soeren; Birkenfeld, Katja; Mulder, Edwin; Rittweger, Jörn; Ledderhos, Carla

    2017-09-01

    The objective assessment of psychophysiological arousal during challenging flight maneuvers is of great interest to aerospace medicine, but remains a challenging task. In the study presented here, a vector-methodological approach was used which integrates different psychophysiological variables, yielding an integral arousal index called the Psychophysiological Arousal Value (PAV). The arousal levels of 15 male pilots were assessed during predetermined, well-defined flight maneuvers performed under simulated and real flight conditions. The physiological data, as expected, revealed inter- and intra-individual differences for the various measurement conditions. As indicated by the PAV, air-to-air refueling (AAR) turned out to be the most challenging task. In general, arousal levels were comparable between simulator and real flight conditions. However, a distinct difference was observed when the pilots were divided by instructors into two groups based on their proficiency in AAR with AWACS (AAR-Novices vs. AAR-Professionals). AAR-Novices had on average more than 2000 flight hours on other aircrafts. They showed higher arousal reactions to AAR in real flight (contact: PAV score 8.4 ± 0.37) than under simulator conditions (7.1 ± 0.30), whereas AAR-Professionals did not (8.5 ± 0.46 vs. 8.8 ± 0.80). The psychophysiological arousal value assessment was tested in field measurements, yielding quantifiable arousal differences between proficiency groups of pilots during simulated and real flight conditions. The method used in this study allows an evaluation of the psychophysiological cost during a certain flying performance and thus is possibly a valuable tool for objectively evaluating the actual skill status of pilots.Johannes B, Rothe S, Gens A, Westphal S, Birkenfeld K, Mulder E, Rittweger J, Ledderhos C. Psychophysiological assessment in pilots performing challenging simulated and real flight maneuvers. Aerosp Med Hum Perform. 2017; 88(9):834-840.

  12. Research of maneuvering target prediction and tracking technology based on IMM algorithm

    Science.gov (United States)

    Cao, Zheng; Mao, Yao; Deng, Chao; Liu, Qiong; Chen, Jing

    2016-09-01

    Maneuvering target prediction and tracking technology is widely used in both military and civilian applications, the study of those technologies is all along the hotspot and difficulty. In the Electro-Optical acquisition-tracking-pointing system (ATP), the primary traditional maneuvering targets are ballistic target, large aircraft and other big targets. Those targets have the features of fast velocity and a strong regular trajectory and Kalman Filtering and polynomial fitting have good effects when they are used to track those targets. In recent years, the small unmanned aerial vehicles developed rapidly for they are small, nimble and simple operation. The small unmanned aerial vehicles have strong maneuverability in the observation system of ATP although they are close-in, slow and small targets. Moreover, those vehicles are under the manual operation, therefore, the acceleration of them changes greatly and they move erratically. So the prediction and tracking precision is low when traditional algorithms are used to track the maneuvering fly of those targets, such as speeding up, turning, climbing and so on. The interacting multiple model algorithm (IMM) use multiple models to match target real movement trajectory, there are interactions between each model. The IMM algorithm can switch model based on a Markov chain to adapt to the change of target movement trajectory, so it is suitable to solve the prediction and tracking problems of the small unmanned aerial vehicles because of the better adaptability of irregular movement. This paper has set up model set of constant velocity model (CV), constant acceleration model (CA), constant turning model (CT) and current statistical model. And the results of simulating and analyzing the real movement trajectory data of the small unmanned aerial vehicles show that the prediction and tracking technology based on the interacting multiple model algorithm can get relatively lower tracking error and improve tracking precision

  13. Driver behavior during bicycle passing maneuvers in response to a Share the Road sign treatment.

    Science.gov (United States)

    Kay, Jonathan J; Savolainen, Peter T; Gates, Timothy J; Datta, Tapan K

    2014-09-01

    The interaction of motorists and bicyclists, particularly during passing maneuvers, is an area of concern to the bicycle safety community as there is a general perception that motor vehicle drivers may not share the road effectively with bicyclists. This is a particular concern on road sections with centerline rumble strips where motorists are prone to crowd bicyclists during passing events. One potential countermeasure to address this concern is the use of a bicycle warning sign with a "Share the Road" plaque. This paper presents the results of a controlled field evaluation of this sign treatment, which involved an examination of driver behavior while overtaking bicyclists. A series of field studies were conducted concurrently on two segments of a high-speed, rural two-lane highway. These segments were similar in terms of roadway geometry, traffic volumes, and other relevant factors, except that one of the segments included centerline rumble strips while the other did not. A before-and-after study design was utilized to examine changes in motor vehicle lateral placement and speed at the time of the passing event as they relate to the presence of centerline rumble strips and the sign treatment. Centerline rumble strips generally shifted vehicles closer to the bicyclists during passing maneuvers, though the magnitude of this effect was marginal. The sign treatment was found to shift motor vehicles away from the rightmost lane positions, though the signs did not significantly affect the mean buffer distance between the bicyclists and passing motorists or the propensity of crowding events during passing. The sign treatment also resulted in a 2.5miles/h (4.0km/h) reduction in vehicle speeds. Vehicle type, bicyclist position, and the presence of opposing traffic were also found to affect lateral placement and speed selection during passing maneuvers.

  14. Residual dizziness after successful repositioning maneuvers for idiopathic benign paroxysmal positional vertigo in the elderly.

    Science.gov (United States)

    Teggi, Roberto; Giordano, Leone; Bondi, Stefano; Fabiano, Beatrice; Bussi, Mario

    2011-04-01

    Even after successful repositioning maneuvers for benign paroxysmal positional vertigo (BPPV), some patients report dizziness lasting for a certain period afterwards. We studied the prevalence and clinical factors associated with residual dizziness in a sample of elderly patients. Sixty outpatients over 65 years of age, affected by idiopathic BPPV were recruited; the exclusion criterion was a history of previous episodes of vertigo, including positional. The patients were asked to describe their self-perceived anxiety for vertigo on a Visual Analogue Scale (VAS) and successively treated with appropriate maneuvers till resolution of nystagmus. Data concerning the demographic and clinical features of BPPV were collected. Patients were followed until complete resolution of subjective dizziness and imbalance without positional nystagmus. Data about residual dizziness were collected from the second day from resolution of BPPV. Clinical and demographic factors related to residual dizziness were analyzed. Twenty-two subjects (37%) reported residual dizziness. In these subjects, the mean duration of residual dizziness was 13.4 ± 7.5 days. No association was observed between residual dizziness and gender, involved canal and the number of repositioning maneuvers before resolution. On the other hand, age older than 72 years, symptom duration greater than 9 days and VAS scale for anxiety greater than 10/100 were associated with an increased risk of residual dizziness. The odds ratio were respectively 6.5 (age-residual dizziness, Confidence Interval 95%), 6.5 (duration of vertigo-residual dizziness, Confidence Interval 95%) and 15.5 (anxiety levels-residual dizziness, Confidence Interval 95%). Longer symptom duration before diagnosis was associated with higher anxiety levels. The results underline the necessity for an early and correct diagnosis of BPPV, especially in the elderly.

  15. 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.

  16. Pressure ulcers

    OpenAIRE

    Monfre, Jill M.

    2011-01-01

    Unrelieved pressure or friction of the skin, particularly over bony prominences, can lead to pressure ulcers, which affect up to one third of people in hospitals or community care, and one fifth of nursing home residents. Pressure ulcers are more likely in people with reduced mobility and poor skin condition, such as older people or those with vascular disease.

  17. MODEL OF CENTRIFUGAL EFFECT AND ATTITUDE MANEUVER STABILITY OF A COUPLED RIGID-FLEXIBLE SYSTEM

    Institute of Scientific and Technical Information of China (English)

    LI Zhi-bin; WANG Zhao-lin; WANG Tian-shu; LIU Ning

    2005-01-01

    The influences of nonlinear centrifugal force to large overall attitude motion of coupled rigid-flexible system was investigated. First the nonlinear model of the coupled rigidflexible system was deduced from the idea of "cenlrifugal potential field", and then the dynamic effects of the nonlinear centrifugal force to system attitude motion were analyzed by approximate calculation; At last, the Lyapunov function based on energy norm was selected,in the condition that only the measured values of attitude and attitude speed are available,and it is proved that the PD feedback control law can ensure the attitude stability during large angle maneuver.

  18. Nonlinear Aerodynamic Modeling From Flight Data Using Advanced Piloted Maneuvers and Fuzzy Logic

    Science.gov (United States)

    Brandon, Jay M.; Morelli, Eugene A.

    2012-01-01

    Results of the Aeronautics Research Mission Directorate Seedling Project Phase I research project entitled "Nonlinear Aerodynamics Modeling using Fuzzy Logic" are presented. Efficient and rapid flight test capabilities were developed for estimating highly nonlinear models of airplane aerodynamics over a large flight envelope. Results showed that the flight maneuvers developed, used in conjunction with the fuzzy-logic system identification algorithms, produced very good model fits of the data, with no model structure inputs required, for flight conditions ranging from cruise to departure and spin conditions.

  19. Dynamics and Control of Three-Dimensional Perching Maneuver under Dynamic Stall Influence

    Science.gov (United States)

    Feroskhan, Mir Alikhan Bin Mohammad

    Perching is a type of aggressive maneuver performed by the class 'Aves' species to attain precision point landing with a generally short landing distance. Perching capability is desirable on unmanned aerial vehicles (UAVs) due to its efficient deceleration process that potentially expands the functionality and flight envelope of the aircraft. This dissertation extends the previous works on perching, which is mostly limited to two-dimensional (2D) cases, to its state-of-the-art threedimensional (3D) variety. This dissertation presents the aerodynamic modeling and optimization framework adopted to generate unprecedented variants of the 3D perching maneuver that include the sideslip perching trajectory, which ameliorates the existing 2D perching concept by eliminating the undesirable undershoot and reliance on gravity. The sideslip perching technique methodically utilizes the lateral and longitudinal drag mechanisms through consecutive phases of yawing and pitching-up motion. Since perching maneuver involves high rates of change in the angles of attack and large turn rates, introduction of three internal variables thus becomes necessary for addressing the influence of dynamic stall delay on the UAV's transient post-stall behavior. These variables are then integrated into a static nonlinear aerodynamic model, developed using empirical and analytical methods, and into an optimization framework that generates a trajectory of sideslip perching maneuver, acquiring over 70% velocity reduction. An impact study of the dynamic stall influence on the optimal perching trajectories suggests that consideration of dynamic stall delay is essential due to the significant discrepancies in the corresponding control inputs required. A comparative study between 2D and 3D perching is also conducted to examine the different drag mechanisms employed by 2D and 3D perching respectively. 3D perching is presented as a more efficient deceleration technique with respect to spatial costs and

  20. On Motion Planning for Point-to-Point Maneuvers for a Class of Sailing Vehicles

    DEFF Research Database (Denmark)

    Xiao, Lin; Jouffroy, Jerome

    2011-01-01

    Despite their interesting dynamic and controllability properties, sailing vehicles have not been much studied in the control community. In this paper, we investigate motion planning of such vehicles. Starting from a simple dynamic model of sailing vessels in one dimension, this paper first...... considers their associated controllability issues, with the so-called no-sailing zone as a starting point, and it links them with a motion planning strategy using two-point boundary value problems as the main mathematical tool. This perspective is then expanded to do point-to-point maneuvers of sailing...

  1. 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...... seek to minimize their anticipated regret from their corrective actions. The model accounts for driver attributes and behavior, critical events that made the crash imminent, vehicle and road characteristics, and environmental conditions. Analyzed data are retrieved from the General Estimates System......-based model, suggesting that both models should serve as a basis for evaluating crash scenarios and driver warning systems....

  2. Slew Maneuver Control for Spacecraft Equipped with Star Camera and Reaction Wheels

    DEFF Research Database (Denmark)

    Wisniewski, Rafal; Kulczycki, P.

    2005-01-01

    A configuration consisting of a star camera, four reaction wheels and magnetorquers for momentum unloading has become standard for many spacecraft missions. This popularity has motivated numerous agencies and private companies to initiate work on the design of an imbedded attitude control system...... realized on an integrated circuit. This paper provides an easily implementable control algorithm for this type of configuration. The paper considers two issues: slew maneuver with a feature of avoiding direct exposure of the camera's CCD chip to the Sun %, three-axis attitude control and optimal control...

  3. Satellite formation flying relative dynamics, formation design, fuel optimal maneuvers and formation maintenance

    CERN Document Server

    Wang, Danwei; Poh, Eng Kee

    2017-01-01

    This book systematically describes the concepts and principles for multi-satellite relative motion, passive and near passive formation designs, trajectory planning and control for fuel optimal formation maneuvers, and formation flying maintenance control design. As such, it provides a sound foundation for researchers and engineers in this field to develop further theories and pursue their implementations. Though satellite formation flying is widely considered to be a major advance in space technology, there are few systematic treatments of the topic in the literature. Addressing that gap, the book offers a valuable resource for academics, researchers, postgraduate students and practitioners in the field of satellite science and engineering.

  4. Sequential maneuvering decisions based on multi-stage influence diagram in air combat

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    A multi-stage influence diagram is used to model the pilot's sequential decision making in one on one air combat.The model based on the multi-stage influence diagram graphically describes the elements of decision process,and contains a point-mass model for the dynamics of an aircraft and takes into account the decision maker's Dreferences under uncertain conditions.Considering an active opponent,the opponent's maneuvers can be modeled stochastically.The solution of multistage influence diagram Can be obtained by converting the multistage influence diagram into a two-level optimization problem.The simulation results show the model is effective.

  5. Spearhead of the Attack: The Role of the Forward Detachment in Tactical Maneuver

    Science.gov (United States)

    1988-10-01

    contemporary war, it is necessary to remember that. science and technology are developing at a stormy pace; and, in all armies, new and new types of weapons...WLbio AL £nducinc. wilitjzI Qperslin in the event of a war, The successes of the Sovie’t U~nion in the area of military technology and weapons have...QhMRD AM IV \\ RMO I OPERATIONAL YFN MOBL TD MANEUVER ARM___RZT OBSTACLE 08N 0RT DETACHMENT OR GROUPBN C MD -T 50-100 TB+RR DN FDM R R T. FORWARD 8N BN

  6. Use of the Orbital Maneuvering Vehicle (OMV) for placement and retrieval of spacecraft and platforms

    Science.gov (United States)

    Snoddy, William C.; Galloway, William E.; Young, Archie C.

    This paper describes the Orbital Maneuvering Vehicle (OMV) and its intended role as a key element of NASA's space infrastructure. Status, plans, and operational modes are summarized. Typical mission scenarios supporting the servicing of spacecraft and platforms from both the Shuttle and the Space Station are described. Particular emphasis is placed on the orbital mechanics associated with the placement and retrieval of spacecraft and platforms. For example, the optimum placement of a Space Station co-orbiting spacecraft in order to maximize the time interval during which it can be retrieved by a Space Station based OMV is shown as a function of the ballistic coefficient of the spacecraft.

  7. Driver Behavior During Overtaking Maneuvers from the 100-Car Naturalistic Driving Study.

    Science.gov (United States)

    Chen, Rong; Kusano, Kristofer D; Gabler, Hampton C

    2015-01-01

    Lane changes with the intention to overtake the vehicle in front are especially challenging scenarios for forward collision warning (FCW) designs. These overtaking maneuvers can occur at high relative vehicle speeds and often involve no brake and/or turn signal application. Therefore, overtaking presents the potential of erroneously triggering the FCW. A better understanding of driver behavior during lane change events can improve designs of this human-machine interface and increase driver acceptance of FCW. The objective of this study was to aid FCW design by characterizing driver behavior during lane change events using naturalistic driving study data. The analysis was based on data from the 100-Car Naturalistic Driving Study, collected by the Virginia Tech Transportation Institute. The 100-Car study contains approximately 1.2 million vehicle miles of driving and 43,000 h of data collected from 108 primary drivers. In order to identify overtaking maneuvers from a large sample of driving data, an algorithm to automatically identify overtaking events was developed. The lead vehicle and minimum time to collision (TTC) at the start of lane change events was identified using radar processing techniques developed in a previous study. The lane change identification algorithm was validated against video analysis, which manually identified 1,425 lane change events from approximately 126 full trips. Forty-five drivers with valid time series data were selected from the 100-Car study. From the sample of drivers, our algorithm identified 326,238 lane change events. A total of 90,639 lane change events were found to involve a closing lead vehicle. Lane change events were evenly distributed between left side and right side lane changes. The characterization of lane change frequency and minimum TTC was divided into 10 mph speed bins for vehicle travel speeds between 10 and 90 mph. For all lane change events with a closing lead vehicle, the results showed that drivers change

  8. Dynamic changes of left ventricular performance and left atrial volume induced by the mueller maneuver in healthy young adults and implications for obstructive sleep apnea, atrial fibrillation, and heart failure.

    Science.gov (United States)

    Orban, Marek; Bruce, Charles J; Pressman, Gregg S; Leinveber, Pavel; Romero-Corral, Abel; Korinek, Josef; Konecny, Tomas; Villarraga, Hector R; Kara, Tomas; Caples, Sean M; Somers, Virend K

    2008-12-01

    Using the Mueller maneuver (MM) to simulate obstructive sleep apnea (OSA), our aim was to investigate acute changes in left-sided cardiac morphologic characteristics and function which might develop with apneas occurring during sleep. Strong evidence supports a relation between OSA and both atrial fibrillation and heart failure. However, acute effects of airway obstruction on cardiac structure and function have not been well defined. In addition, it is unclear how OSA might contribute to the development of atrial fibrillation and heart failure. Echocardiography was used in healthy young adults to measure various parameters of cardiac structure and function. Subjects were studied at baseline, during, and immediately after performance of the MM and after a 10-minute recovery. Continuous heart rate, blood pressure, and pulse oximetry measurements were made. During the MM, left atrial (LA) volume index markedly decreased. Left ventricular (LV) end-systolic dimension increased in association with a decrease in LV ejection fraction. On release of the maneuver, there was a compensatory increase in blood flow to the left side of the heart, with stroke volume, ejection fraction, and cardiac output exceeding baseline. After 10 minutes of recovery, all parameters returned to baseline. In conclusion, sudden imposition of severe negative intrathoracic pressure led to an abrupt decrease in LA volume and a decrease in LV systolic performance. These changes reflected an increase in LV afterload. Repeated swings in afterload burden and chamber volumes may have implications for the future development of atrial fibrillation and heart failure.

  9. Effect of Repositioning Maneuver Type and Postmaneuver Restrictions on Vertigo and Dizziness in Benign Positional Paroxysmal Vertigo

    Directory of Open Access Journals (Sweden)

    Michel Toupet

    2012-01-01

    Full Text Available Introduction. To compare the efficiency of Epley (Ep and Sémont-Toupet (ST repositioning maneuvers and to evaluate postmaneuver restriction effect on short-term vertigo and dizziness after repositioning maneuvers by an analog visual scale (VAS in benign positional paroxysmal vertigo (BPPV. Material and Methods. 226 consecutive adult patients with posterior canal BPPV were included. Patients were randomized into 2 different maneuver sequence groups (n=113: 2 ST then 1 Ep or 2 Ep then 1 ST. Each group of sequence was randomized into 2 subgroups: with or without postmaneuver restrictions. Vertigo and dizziness were assessed from days 0 to 5 by VAS. Results. There was no difference between vertigo scores between Ep and ST groups. Dizziness scores were higher in Ep group during the first 3 days but became similar to those of ST group at days 4 and 5. ST maneuvers induced liberatory signs more frequently than Ep (58% versus 42% resp., P<0.01, Fisher's test. After repositioning maneuvers, VAS scores decreased similarly in patients with and without liberatory signs. Postmaneuver restrictions did not influence VAS scores. Conclusion. Even if ST showed a higher rate of liberatory signs than Ep in this series, VAS scores were not influenced by these signs.

  10. Ocular VEMPs indicate repositioning of otoconia to the utricle after successful liberatory maneuvers in benign paroxysmal positioning vertigo

    Science.gov (United States)

    BREMOVA, TATIANA; BAYER, OTMAR; AGRAWAL, YURI; KREMMYDA, OLYMPIA; BRANDT, THOMAS; TEUFEL, JULIAN; STRUPP, MICHAEL

    2014-01-01

    Conclusions This study showed a transient increase of ocular vestibular evoked myogenic potential (oVEMP) amplitudes in the affected ear after successful liberatory maneuvers and no changes in cervical VEMP (cVEMP) amplitudes. These findings support the hypothesis that successful liberatory maneuvers can lead to a repositioning of otoconia to the utricle. Objectives To evaluate whether oVEMP amplitudes increase after successful liberatory maneuvers in patients with posterior semicircular canal benign paroxysmal positioning vertigo (pc-BPPV), while cVEMP amplitudes do not change. These findings may indicate a successful repositioning of dislodged otoconia to the utricular macula, but not to the saccular macula. Methods Thirty patients with unilateral pc-BPPV were prospectively examined with bone-conducted oVEMP and air-conducted cVEMP at four time points: before, after, 1 week after, and 1 month after the liberatory maneuvers (Sémont maneuvers). Results At the 1-week follow-up, 20 of 30 patients were asymptomatic (responders); BPPV could still be induced in the other 10 (non-responders). In responders the mean n10 amplitude on the affected side increased from 12 ± 6.5 μV at baseline (before the treatment) to 15.9 ± 7.1 μV at 1 week after treatment; this increase was significantly (p = 0.001) higher in responders than in non-responders. cVEMP did not differ significantly. PMID:24245699

  11. Effect of Repositioning Maneuver Type and Postmaneuver Restrictions on Vertigo and Dizziness in Benign Positional Paroxysmal Vertigo

    Science.gov (United States)

    Toupet, Michel; Ferrary, Evelyne; Bozorg Grayeli, Alexis

    2012-01-01

    Introduction. To compare the efficiency of Epley (Ep) and Sémont-Toupet (ST) repositioning maneuvers and to evaluate postmaneuver restriction effect on short-term vertigo and dizziness after repositioning maneuvers by an analog visual scale (VAS) in benign positional paroxysmal vertigo (BPPV). Material and Methods. 226 consecutive adult patients with posterior canal BPPV were included. Patients were randomized into 2 different maneuver sequence groups (n = 113): 2 ST then 1 Ep or 2 Ep then 1 ST. Each group of sequence was randomized into 2 subgroups: with or without postmaneuver restrictions. Vertigo and dizziness were assessed from days 0 to 5 by VAS. Results. There was no difference between vertigo scores between Ep and ST groups. Dizziness scores were higher in Ep group during the first 3 days but became similar to those of ST group at days 4 and 5. ST maneuvers induced liberatory signs more frequently than Ep (58% versus 42% resp., P < 0.01, Fisher's test). After repositioning maneuvers, VAS scores decreased similarly in patients with and without liberatory signs. Postmaneuver restrictions did not influence VAS scores. Conclusion. Even if ST showed a higher rate of liberatory signs than Ep in this series, VAS scores were not influenced by these signs. PMID:22973168

  12. A Proposed Maneuver to Guide Transseptal Puncture Using Real-Time Three-Dimensional Transesophageal Echocardiography: Pilot Study

    Directory of Open Access Journals (Sweden)

    Hani M. Mahmoud

    2015-01-01

    Full Text Available Aim of Study. To assess the feasibility of a new proposed maneuver “RATLe-90” using real-time three-dimensional transesophageal echocardiography (RT-3DTEE for anatomically oriented visualization of the interatrial septum (IAS in guiding the transseptal puncture TSP. Methods. The study included 20 patients (mean age, 60.2±6.7 years; 60% males who underwent TSP for different indications. RT-3DTEE was used to guide TSP. The proposed maneuver RATLe-90 (Rotate-Anticlockwise-Tilt-Left-90 was applied in all cases to have the anatomically oriented en face view of the IAS from the right atrial (RA aspect. Having this anatomically oriented view, we guided the TSP catheter towards the proper puncture site according to the planned procedure. Results. Using the RATLe-90 maneuver, the anatomically oriented en face view of the IAS from the RA was obtained in all patients. We were able to guide the puncture catheter to the proper puncture site on the IAS. The 3D images obtained were clearly understood by both echocardiographers and interventionists. The RATLe-90 maneuver acquisition time was 19.9±1.6 seconds. The time-to-tent was 64.8±16.3 seconds. Less TEE probe manipulations were needed while guiding the TSP. Conclusions. Application of RT3D-TEE during TSP using RATLe-90 maneuver is feasible with shorter fluoroscopy time and minimizing TEE probe manipulations.

  13. Ocular VEMPs indicate repositioning of otoconia to the utricle after successful liberatory maneuvers in benign paroxysmal positioning vertigo.

    Science.gov (United States)

    Bremova, Tatiana; Bayer, Otmar; Agrawal, Yuri; Kremmyda, Olympia; Brandt, Thomas; Teufel, Julian; Strupp, Michael

    2013-12-01

    This study showed a transient increase of ocular vestibular evoked myogenic potential (oVEMP) amplitudes in the affected ear after successful liberatory maneuvers and no changes in cervical VEMP (cVEMP) amplitudes. These findings support the hypothesis that successful liberatory maneuvers can lead to a repositioning of otoconia to the utricle. To evaluate whether oVEMP amplitudes increase after successful liberatory maneuvers in patients with posterior semicircular canal benign paroxysmal positioning vertigo (pc-BPPV), while cVEMP amplitudes do not change. These findings may indicate a successful repositioning of dislodged otoconia to the utricular macula, but not to the saccular macula. Thirty patients with unilateral pc-BPPV were prospectively examined with bone-conducted oVEMP and air-conducted cVEMP at four time points: before, after, 1 week after, and 1 month after the liberatory maneuvers (Sémont maneuvers). At the 1-week follow-up, 20 of 30 patients were asymptomatic (responders); BPPV could still be induced in the other 10 (non-responders). In responders the mean n10 amplitude on the affected side increased from 12 ± 6.5 µV at baseline (before the treatment) to 15.9 ± 7.1 µV at 1 week after treatment; this increase was significantly (p = 0.001) higher in responders than in non-responders. cVEMP did not differ significantly.

  14. THE EFFECT OF CORE EXERCISES ON TRANSDIAPHRAGMATIC PRESSURE

    Directory of Open Access Journals (Sweden)

    Lisa M. Strongoli

    2010-06-01

    Full Text Available Abdominal exercises, such as sit ups and leg lifts, are used to enhance strength of the core muscles. An overlooked aspect of abdominal exercises is the compression the abdomen, leading to increased diaphragmatic work. We hypothesized that core exercises would produce a variety of transdiaphragmatic pressures. We also sought to determine if some of the easy exercises would produce pressures sufficient for a training stimulus to the diaphragm. We evaluated the effect of 13 different abdominal exercises, ranging in difficulty, on transdiaphragmatic pressure (Pdi, an index of diaphragmatic activity. Six healthy subjects, aged 22 to 53, participated. Each subject was instrumented with two balloon-tipped catheters to obtain gastric and esophageal pressures, from which Pdi was calculated. Prior to initiating the exercises, each subject performed a maximal inspiratory pressure (MIP maneuver. Resting Pdi was also measured. The exercises were performed from least to most difficult, with five repetitions each. There was a significant difference between the exercises and the MIP Pdi, as well as between the exercises and resting Pdi (p 50% of the Pdi during the MIP maneuver, which may provide a training stimulus to the diaphragm if used as a regular exercise. The Pdi measurements also provide insight into diaphragm recruitment during different core exercises, and may aid in the design of exercises to improve diaphragm strength and endurance

  15. Cardiovascular responses to passive static flexibility exercises are influenced by the stretched muscle mass and the Valsalva maneuver

    Directory of Open Access Journals (Sweden)

    Paulo T. V Farinatti

    2011-01-01

    Full Text Available BACKGROUND: The respiratory pattern is often modified or even blocked during flexibility exercises, but little is known about the cardiovascular response to concomitant stretching and the Valsalva maneuver (VM in healthy subjects. OBJECTIVES: This study evaluated the heart rate (HR, systolic blood pressure (SBP, and rate-pressure product (RPP during and after large and small muscle group flexibility exercises performed simultaneously with the VM. METHODS: Asymptomatic volunteers (N = 22 with the following characteristics were recruited: age, 22 ± 3 years; weight, 73 ± 6 kg; height, 175 ± 5 cm; HR at rest, 66 ± 9 BPM; and SBP at rest, 113 ± 10 mmHg. They performed two exercises: four sets of passive static stretching for 30 s of the dorsi-flexion (DF of the gastrocnemius and the hip flexion (HF of the ischio-tibialis. The exercises were performed with (V+ or without (V- the VM in a counterbalanced order. The SBP and HR were measured, and the RPP was calculated before the exercise session, at the end of each set, and during a 30-min post-exercise recovery period. RESULTS: The within-group comparisons showed that only the SBP and RPP increased throughout the sets (p<0.05, but no post-exercise hypotension was detected. The between-group comparisons showed that greater SBP increases were related to the VM and to a larger stretched muscle mass. Differences for a given set were identified for the HR (the HFV+ and HFV- values were higher than the DFV+ and DFV- values by approximately 12 BPM, SBP (the HFV+ value was higher than the DFV+ and DFV- values by approximately 12 to 15 mmHg, and RPP (the HFV+ value was higher than the HFV- value by approximately 2000 mmHGxBPM, and the HFV+ value was higher than the DFV+ and DFV- values by approximately 4000 mmHGxBPM. CONCLUSION: Both the stretched muscle mass and the VM influence acute cardiovascular responses to multiple-set passive stretching exercise sessions.

  16. Cardiovascular responses to passive static flexibility exercises are influenced by the stretched muscle mass and the Valsalva maneuver

    Science.gov (United States)

    Farinatti, Paulo T V; Soares, Pedro P S; Monteiro, Walace D; Duarte, Antonio F A; Viveiros de Castro, Luis A

    2011-01-01

    BACKGROUND: The respiratory pattern is often modified or even blocked during flexibility exercises, but little is known about the cardiovascular response to concomitant stretching and the Valsalva maneuver (VM) in healthy subjects. OBJECTIVES: This study evaluated the heart rate (HR), systolic blood pressure (SBP), and rate-pressure product (RPP) during and after large and small muscle group flexibility exercises performed simultaneously with the VM. METHODS: Asymptomatic volunteers (N  =  22) with the following characteristics were recruited: age, 22 ± 3 years; weight, 73 ± 6 kg; height, 175 ± 5 cm; HR at rest, 66 ± 9 BPM; and SBP at rest, 113 ± 10 mmHg. They performed two exercises: four sets of passive static stretching for 30 s of the dorsi-flexion (DF) of the gastrocnemius and the hip flexion (HF) of the ischio-tibialis. The exercises were performed with (V+) or without (V-) the VM in a counterbalanced order. The SBP and HR were measured, and the RPP was calculated before the exercise session, at the end of each set, and during a 30-min post-exercise recovery period. RESULTS: The within-group comparisons showed that only the SBP and RPP increased throughout the sets (p<0.05), but no post-exercise hypotension was detected. The between-group comparisons showed that greater SBP increases were related to the VM and to a larger stretched muscle mass. Differences for a given set were identified for the HR (the HFV+ and HFV- values were higher than the DFV+ and DFV- values by approximately 12 BPM), SBP (the HFV+ value was higher than the DFV+ and DFV- values by approximately 12 to 15 mmHg), and RPP (the HFV+ value was higher than the HFV- value by approximately 2000 mmHGxBPM, and the HFV+ value was higher than the DFV+ and DFV- values by approximately 4000 mmHGxBPM). CONCLUSION: Both the stretched muscle mass and the VM influence acute cardiovascular responses to multiple-set passive stretching exercise sessions. PMID:21552673

  17. Direct Lyapunov-based control law design for spacecraft attitude maneuvers

    Institute of Scientific and Technical Information of China (English)

    HU Likun; ANG Qingchao

    2006-01-01

    A direct Lyapunov-based control law is presented to perform on-orbit stability for spacecraft attitude maneuvers. Spacecraft attitude kinematic equations and dynamic equations are coupled, nonlinear, multi-input multi-output(MIMO), which baffles controller design. Orbit angular rates are taken into account in kinematic equations and influence of gravity gradient moments and disturbance moments on the spacecraft attitude in dynamic equations is considered to approach the practical environment, which enhance the problem complexity to some extent. Based on attitude tracking errors and angular rates, a Lyapunov function is constructed, through which the stabilizing feedback control law is deduced via Lie derivation of the Lyapunov function. The proposed method can deal with the case that the spacecraft is subjected to mass property variations or centroidal inertia matrix variations due to fuel assumption or flexibility, and disturbance moments, which shows the proposed controller is robust for spacecraft attitude maneuvers. The unlimited controller and the limited controller are taken into account respectively in simulations. Simulation results are demonstrated to validate effectiveness and feasibility of the proposed method.

  18. Piloted Simulator Evaluation of Maneuvering Envelope Information for Flight Crew Awareness

    Science.gov (United States)

    Lombaerts, Thomas; Schuet, Stefan; Acosta, Diana; Kaneshige, John; Shish, Kimberlee; Martin, Lynne

    2015-01-01

    The implementation and evaluation of an efficient method for estimating safe aircraft maneuvering envelopes are discussed. A Bayesian approach is used to produce a deterministic algorithm for estimating aerodynamic system parameters from existing noisy sensor measurements, which are then used to estimate the trim envelope through efficient high- fidelity model-based computations of attainable equilibrium sets. The safe maneuverability limitations are extended beyond the trim envelope through a robust reachability analysis derived from an optimal control formulation. The trim and maneuvering envelope limits are then conveyed to pilots through three axes on the primary flight display. To evaluate the new display features, commercial airline crews flew multiple challenging approach and landing scenarios in the full motion Advanced Concepts Flight Simulator at NASA Ames Research Center, as part of a larger research initiative to investigate the impact on the energy state awareness of the crew. Results show that the additional display features have the potential to significantly improve situational awareness of the flight crew.

  19. Aerodynamic Interactions Between Wing and Body of a Model Insect in Forward Flight and Maneuvers

    Institute of Scientific and Technical Information of China (English)

    Bin Liang; Mao Sun

    2013-01-01

    The aerodynamic interactions between the body and the wings of a model insect in forward flight and maneuvers are studied using the method of numerically solving the Navier-Stokes equations over moving overset grids.Three cases are considered,including a complete insect,wing pair only and body only.By comparing the results of these cases,the interaction effect between the body and the wing pair can be identified.The changes in the force and moment coefficients of the wing pair due to the presence of the body are less than 4.5% of the mean vertical force coefficient of the model insect; the changes in the aerodynamic force coefficients of the body due to the presence of the wings are less than 5.0% of the mean vertical force coefficient of the model insect.The results of this paper indicate that in studying the aerodynamics and flight dynamics of a flapping insect in forward flight or maneuver,separately computing (or measuring) the aerodynamic forces and moments on the wing pair and on the body could be a good approximation.

  20. Navigation of C. elegans in three-dimensional media: roll maneuvers and planar turns

    CERN Document Server

    Bilbao, Alejandro; Rahman, Mizanur; Vanapalli, Siva A; Blawzdziewicz, Jerzy

    2016-01-01

    Free-living nematode Caenorhabditis elegans is a powerful genetic model, essential for investigations ranging from behavior to neuroscience to aging, and locomotion is a key observable used in these studies. However, despite the fact that in its natural environment C. elegans moves in three-dimensional (3D) complex media (decomposing organic matter and water), quantitative in vestigations of its locomotion have been limited to two-dimensional (2D) motion. Based on our recent quantitative analysis of 2D turning maneuvers [Phys. Fluids 25, 081902 (2013)] we follow with the first quantitative description of how C. elegans moves in 3D environments. We show that by superposing body torsion and 2D undulations, a burrowing or swimming nematode can rotate the undulation plane. A combination of these roll maneuvers and 2D turns associated with variation of undulation-wave parameters allows the nematode to explore 3D space. We apply our model to analyze 3D chemotaxis of nematodes burrowing in a gel and swimming in wate...

  1. Ultra-fast escape maneuver of an octopus-inspired robot.

    Science.gov (United States)

    Weymouth, G D; Subramaniam, V; Triantafyllou, M S

    2015-02-02

    We design and test an octopus-inspired flexible hull robot that demonstrates outstanding fast-starting performance. The robot is hyper-inflated with water, and then rapidly deflates to expel the fluid so as to power the escape maneuver. Using this robot we verify for the first time in laboratory testing that rapid size-change can substantially reduce separation in bluff bodies traveling several body lengths, and recover fluid energy which can be employed to improve the propulsive performance. The robot is found to experience speeds over ten body lengths per second, exceeding that of a similarly propelled optimally streamlined rigid rocket. The peak net thrust force on the robot is more than 2.6 times that on an optimal rigid body performing the same maneuver, experimentally demonstrating large energy recovery and enabling acceleration greater than 14 body lengths per second squared. Finally, over 53% of the available energy is converted into payload kinetic energy, a performance that exceeds the estimated energy conversion efficiency of fast-starting fish. The Reynolds number based on final speed and robot length is [Formula: see text]. We use the experimental data to establish a fundamental deflation scaling parameter [Formula: see text] which characterizes the mechanisms of flow control via shape change. Based on this scaling parameter, we find that the fast-starting performance improves with increasing size.

  2. Multiobjective Simulated Annealing for Collision Avoidance in ATM Accounting for Three Admissible Maneuvers

    Directory of Open Access Journals (Sweden)

    A. Mateos

    2016-01-01

    Full Text Available Technological advances are required to accommodate air traffic control systems for the future growth of air traffic. Particularly, detection and resolution of conflicts between aircrafts is a problem that has attracted much attention in the last decade becoming vital to improve the safety standards in free flight unstructured environments. We propose using the archive simulated annealing-based multiobjective optimization algorithm to deal with such a problem, accounting for three admissible maneuvers (velocity, turn, and altitude changes in a multiobjective context. The minimization of the maneuver number and magnitude, time delays, or deviations in the leaving points are considered for analysis. The optimal values for the algorithm parameter set are identified in the more complex instance in which all aircrafts have conflicts between each other accounting for 5, 10, and 20 aircrafts. Moreover, the performance of the proposed approach is analyzed by means of a comparison with the Pareto front, computed using brute force for 5 aircrafts and the algorithm is also illustrated with a random instance with 20 aircrafts.

  3. An adaptive guidance algorithm for an aerodynamically assisted orbital plane change maneuver. M.S. Thesis

    Science.gov (United States)

    Blissit, J. A.

    1986-01-01

    Using analysis results from the post trajectory optimization program, an adaptive guidance algorithm is developed to compensate for density, aerodynamic and thrust perturbations during an atmospheric orbital plane change maneuver. The maneuver offers increased mission flexibility along with potential fuel savings for future reentry vehicles. Although designed to guide a proposed NASA Entry Research Vehicle, the algorithm is sufficiently generic for a range of future entry vehicles. The plane change analysis provides insight suggesting a straight-forward algorithm based on an optimized nominal command profile. Bank angle, angle of attack, and engine thrust level, ignition and cutoff times are modulated to adjust the vehicle's trajectory to achieve the desired end-conditions. A performance evaluation of the scheme demonstrates a capability to guide to within 0.05 degrees of the desired plane change and five nautical miles of the desired apogee altitude while maintaining heating constraints. The algorithm is tested under off-nominal conditions of + or -30% density biases, two density profile models, + or -15% aerodynamic uncertainty, and a 33% thrust loss and for various combinations of these conditions.

  4. Optimization of dynamic soaring maneuvers to enhance endurance of a versatile UAV

    Science.gov (United States)

    Mir, Imran; Maqsood, Adnan; Akhtar, Suhail

    2017-06-01

    Dynamic soaring is a process of acquiring energy available in atmospheric wind shears and is commonly exhibited by soaring birds to perform long distance flights. This paper aims to demonstrate a viable algorithm which can be implemented in near real time environment to formulate optimal trajectories for dynamic soaring maneuvers for a small scale Unmanned Aerial Vehicle (UAV). The objective is to harness maximum energy from atmosphere wind shear to improve loiter time for Intelligence, Surveillance and Reconnaissance (ISR) missions. Three-dimensional point-mass UAV equations of motion and linear wind gradient profile are used to model flight dynamics. Utilizing UAV states, controls, operational constraints, initial and terminal conditions that enforce a periodic flight, dynamic soaring problem is formulated as an optimal control problem. Optimized trajectories of the maneuver are subsequently generated employing pseudo spectral techniques against distant UAV performance parameters. The discussion also encompasses the requirement for generation of optimal trajectories for dynamic soaring in real time environment and the ability of the proposed algorithm for speedy solution generation. Coupled with the fact that dynamic soaring is all about immediately utilizing the available energy from the wind shear encountered, the proposed algorithm promises its viability for practical on board implementations requiring computation of trajectories in near real time.

  5. Application of the Kalman Filter to Estimate the State of an Aerobraking Maneuver

    Directory of Open Access Journals (Sweden)

    Willer Gomes dos Santos

    2013-01-01

    Full Text Available This paper presents a study about the application of a Kalman filter to estimate the position and velocity of a spacecraft in an aerobraking maneuver around the Earth. The cis-lunar aerobraking of the Hiten spacecraft as well as an aerobraking in a LEO orbit are simulated in this paper. The simulator developed considers a reference trajectory and a trajectory perturbed by external disturbances combined with nonidealities of sensors and actuators. It is able to operate in closed loop controlling the trajectory at each instant of time using a PID controller and propulsive jets. A Kalman filter utilizes the sensor data to estimate the state of the spacecraft. The estimation algorithms and propagation equations used in this process are presented. The U.S. Standard Atmosphere is adopted as the atmospheric model. The main results are compared with the case where the Kalman filter is not used. Therefore, it was possible to perform an analysis of the Kalman filter importance applied to an aerobraking maneuver.

  6. An Analysis Nomoto Gain and Norbin Parameter on Ship Turning Maneuver

    Directory of Open Access Journals (Sweden)

    Aulia Siti Aisjah

    2010-05-01

    Full Text Available First order approach of maneuvering ship model developed by Nomoto, that has commonly underpinned researchers on mathematical models of ship maneuvering, is employed by the present research in order to describe the results of Nomoto validation gain value from some type of ships. In this present study, the controls are designated using FLC, while the rules are derived from FLC; furthermore, the reference is the LQG/LTR. On the other pole, Norbin parameters are obtained under the bases of the gain and time constant output control response. Validation of Nomoto gain value is obtained through the calculation of the value of a constant gain, settling time of the first order response, and approach value toward damping ratio and natural frequency response of the system used to control the output of the second order pattern. Validation is employed on 20 types of ships with a length between 40-350 meters; as a result, it is figured out that at the Low Speed General Cargo ship, Mariner, RO/RO, and Barge Carrier have good maneuverability compared to the other 17 types of ships.

  7. Directionality and maneuvering effects on a surface ship underwater acoustic signature.

    Science.gov (United States)

    Trevorrow, Mark V; Vasiliev, Boris; Vagle, Svein

    2008-08-01

    This work examines underwater source spectra of a small (560 tons, 40 m length), single-screw oceanographic vessel, focusing on directionality and effects of maneuvers. The measurements utilized a set of four, self-contained buoys with GPS positioning, each recording two calibrated hydrophones with effective acoustic bandwidth from 150 Hz to 5 kHz. In straight, constant-speed runs at speeds up to 6.2 m s(-1), the ship source spectra showed spectral levels in reasonable agreement with reference spectra. The broadband source level was observed to increase as approximately speed to the fourth power over the range of 2.6-6.1 m s(-1), partially biased at low speeds by nonpropulsion machinery signals. Source directionality patterns were extracted from variations in source spectra while the ship transited past the buoy field. The observed spectral source levels exhibited a broadside maximum, with bow and stern aspect reduced by approximately 12-9 dB, respectively, independent of frequency. An empirical model is proposed assuming that spectral source levels exhibit simultaneous variations in aspect angle, speed, and turn rate. After correction for source directionality and speed during turning maneuvers, an excess of up to 18 dB in one-third octave source levels was observed.

  8. Spacecraft attitude maneuver control using two parallel mounted 3-DOF spherical actuators

    Directory of Open Access Journals (Sweden)

    Guidan Li

    2017-02-01

    Full Text Available A parallel configuration using two 3-degree-of-freedom (3-DOF spherical electromagnetic momentum exchange actuators is investigated for large angle spacecraft attitude maneuvers. First, the full dynamic equations of motion for the spacecraft system are derived by the Newton-Euler method. To facilitate computation, virtual gimbal coordinate frames are established. Second, a nonlinear control law in terms of quaternions is developed via backstepping method. The proposed control law compensates the coupling torques arising from the spacecraft rotation, and is robust against the external disturbances. Then, the singularity problem is analyzed. To avoid singularities, a modified weighed Moore-Pseudo inverse velocity steering law based on null motion is proposed. The weighted matrices are carefully designed to switch the actuators and redistribute the control torques. The null motion is used to reorient the rotor away from the tilt angle saturation state. Finally, numerical simulations of rest-to-rest maneuvers are performed to validate the effectiveness of the proposed method.

  9. User acceptance of cooperative maneuver-based driving--a summary of three studies.

    Science.gov (United States)

    Kauer, Michaela; Franz, Benjamin; Schreiber, Michael; Bruder, Ralph; Geyer, Sebastian

    2012-01-01

    Modern cars offer drivers support with the help of a number of driver assistance systems. Those systems aim to relieve drivers through assumption of sub parts of the driving task (e.g. in case of an Adaptive Cruise Control by regulation of vehicle speed and time gap to preceding vehicle). Today, systems are controlled and monitored separately which leads to efforts to combine the functionality of all systems in an overlying assistance for drivers. The approach of the University of Technology Darmstadt is called Conduct-by-Wire and can be seen as a cooperative maneuver-based driving paradigm, where the driver gives maneuver command to the systems which are automatically executed. This paper summarizes the results of three studies which investigated the user acceptance of this driving paradigm. Overall, it can be said that the acceptance of the system depends on personal traits of the driver and on the driving situation. Almost all participants are willing to use Conduct-by- Wire for routine tasks such as commuting, which makes the systems interesting for company cars. Still, there remain a number of drivers who are not willing to use such a highly automated system at all.

  10. A Sampling Based Approach to Spacecraft Autonomous Maneuvering with Safety Specifications

    Science.gov (United States)

    Starek, Joseph A.; Barbee, Brent W.; Pavone, Marco

    2015-01-01

    This paper presents a methods for safe spacecraft autonomous maneuvering that leverages robotic motion-planning techniques to spacecraft control. Specifically the scenario we consider is an in-plan rendezvous of a chaser spacecraft in proximity to a target spacecraft at the origin of the Clohessy Wiltshire Hill frame. The trajectory for the chaser spacecraft is generated in a receding horizon fashion by executing a sampling based robotic motion planning algorithm name Fast Marching Trees (FMT) which efficiently grows a tree of trajectories over a set of probabillistically drawn samples in the state space. To enforce safety the tree is only grown over actively safe samples for which there exists a one-burn collision avoidance maneuver that circularizes the spacecraft orbit along a collision-free coasting arc and that can be executed under potential thrusters failures. The overall approach establishes a provably correct framework for the systematic encoding of safety specifications into the spacecraft trajectory generations process and appears amenable to real time implementation on orbit. Simulation results are presented for a two-fault tolerant spacecraft during autonomous approach to a single client in Low Earth Orbit.

  11. Decision making and experience level influence frontal plane knee joint biomechanics during a cutting maneuver.

    Science.gov (United States)

    Kipp, Kristof; Brown, Tyler N; McLean, Scott G; Palmieri-Smith, Riann M

    2013-12-01

    The purpose of this study was to examine the combined impact of experience and decision making on frontal plane knee joint biomechanics during a cutting maneuver. Kinematic and kinetic data were collected from 12 recreationally active and 18 NCAA Division I female athletes during execution of anticipated and unanticipated single-leg land-and-cut maneuvers. Knee joint abduction angles and external knee joint abduction torques were calculated and discrete peak stance-phase variables were extracted. Angle and torque time-series data were also submitted to separate functional data analyses. Variables derived from the functional data analyses indicated that decision making influenced knee abduction angle and torque time series in the recreational group only. Specifically, these variables pointed to greater knee abduction at the end of stance as well as a greater, albeit delayed peak in knee abduction torque at the beginning of landing in the recreational athletes during the unanticipated condition. In addition, the recreational athletes displayed greater discrete peak knee abduction angles than the Division I athletes regardless of condition. Discrete peak knee abduction torque did not differ between groups or conditions.

  12. Tracking a maneuvering target in clutter with out-of-sequence measurements for airborne radar

    Institute of Scientific and Technical Information of China (English)

    Weihua Wu; Jing Jiang; Yang Wan

    2015-01-01

    There are many proposed optimal or suboptimal al-gorithms to update out-of-sequence measurement(s) (OoSM(s)) for linear-Gaussian systems, but few algorithms are dedicated to track a maneuvering target in clutter by using OoSMs. In order to address the nonlinear OoSMs obtained by the airborne radar located on a moving platform from a maneuvering target in clut-ter, an interacting multiple model probabilistic data association (IMMPDA) algorithm with the OoSM is developed. To be practical, the algorithm is based on the Earth-centered Earth-fixed (ECEF) coordinate system where it considers the effect of the platform’s attitude and the curvature of the Earth. The proposed method is validated through the Monte Carlo test compared with the perfor-mance of the standard IMMPDA algorithm ignoring the OoSM, and the conclusions show that using the OoSM can improve the track-ing performance, and the shorter the lag step is, the greater degree the performance is improved, but when the lag step is large, the performance is not improved any more by using the OoSM, which can provide some references for engineering application.

  13. Numerical Investigation of Bending-Body Projectile Aerodynamics for Maneuver Control

    Science.gov (United States)

    Youn, Eric; Silton, Sidra

    2015-11-01

    Precision munitions are an active area of research for the U.S. Army. Canard-control actuators have historically been the primary mechanism used to maneuver fin-stabilized, gun-launched munitions. Canards are small, fin-like control surfaces mounted at the forward section of the munition to provide the pitching moment necessary to rotate the body in the freestream flow. The additional lift force due to the rotated body and the canards then alters the flight path toward the intended target. As velocity and maneuverability requirements continue to increase, investigation of other maneuver mechanisms becomes necessary. One option for a projectile with a large length-to-diameter ratio (L/D) is a bending-body design, which imparts a curvature to the projectile body along its axis. This investigation uses full Navier-Stokes computational fluid dynamics simulations to evaluate the effectiveness of an 8-degree bent nose tip on an 8-degree bent forward section of an L/D =10 projectile. The aerodynamic control effectiveness of the bending-body concept is compared to that of a standard L/D =10 straight-body projectile as well as that of the same projectile with traditional canards. All simulations were performed at supersonic velocities between Mach 2-4.

  14. Optimal Flight to Near-Earth Asteroids with Using Electric Propulsion and Gravity Maneuvers

    Science.gov (United States)

    Chernov, A. V.

    Optimal space flight to near-Earth asteroid for deflection asteroids from the Earth and prevention their possible collision is investigated. The deflection is realized by means of impact-kinetic effect of the spacecraft on the asteroid and changing the asteroid orbit. The effectiveness of this method for preventing asteroid-Earth collision is estimated by means of optimal space flights, which are found. The flight of spacecraft (SC) is realized by means of using electric propulsion system. To increase effectiveness the optimal gravity maneuvers of spacecraft near Mars and Venus are using. Criterion of the space flight optimization is maximal deflection of the asteroid from the Earth at the moment of asteroid-Earth nearest approach. For determination of optimal trajectories the maximum Pontrjagin principle is used. It is assumed that the thrust of electric propulsion is unrestricted or corresponding to electric engine SPT-140 with solar battery as energy source. The technique of choice of first approximation for optimal trajectory determination on base of search optimal trajectories in more simple statement is used. The optimal trajectories are determined for wide ranges of the space flight times to near-Earth asteroids with different orbit elements. A comparison with a case of the space flight using a high thrust only or without gravity-assisted maneuvers is carried out.

  15. Effects of the eccentricity of the primaries in powered Swing-By maneuvers

    Science.gov (United States)

    Ferreira, Alessandra F. S.; Prado, Antônio F. B. A.; Winter, Othon C.; Santos, Denilson P. S.

    2017-04-01

    The present paper studies the powered Swing-By maneuver when performed in an elliptical system of primaries. It means that there is a spacecraft travelling in a system governed by the gravity fields of two bodies that are in elliptical orbits around their center of mass. The paper particularly analyzes the effects of the parameters relative to the Swing-By (Vinf-,rp, ψ), the orbit of the secondary body around the primary one (e, ν) and the elements that specify the impulse applied (δV, α) to the spacecraft. The impulse is applied when the spacecraft passes by the periapsis of its orbit around the body, where it performs the Swing-By, with different magnitudes and directions. The inclusion of the orbital eccentricity of the primaries in this problem makes it closer to reality, considering that there are many known systems with eccentricities different from zero. In particular, there are several moons in the Solar System which orbits are not circular, as well as some smaller bodies, like the dwarf planet Haumea and its moons, which have eccentricities of 0.25 or even larger. The behavior of the energy variation of the spacecraft is shown in details, as well as the cases where captures and collisions occur. The results show the conditions that optimize this maneuver, according to some given parameters, and how much can be obtained in terms of gains or losses of energy using the best conditions found by the algorithm developed here.

  16. Directional solidification of flake and nodular cast iron during KC-135 low-g maneuvers

    Science.gov (United States)

    Curreri, P. A.; Stefanescu, D. M.; Hendrix, J. C.

    1984-01-01

    Alloys solidified in a low-gravity environment can, due to the elimination of sedimentation and convection, form unique and often desirable microstructures. One method of studying the effects of low-gravity (low-g) on alloy solidification was the use of the NASA KC-135 aircraft flying repetitive low-g maneuvers. Each maneuver gives from 20 to 30 seconds of low-g which is between about 0.1 and 0.001 gravity. A directional solidification furnace was used to study the behavior of off eutectic composition case irons in a low-g environment. The solidification interface of hypereutectic flake and spheroidal graphite case irons was slowly advanced through a rod sample, 5 mm in diameter. Controlled solidification was continued through a number of aircraft parabolas. The known solidification rate of the sample was then correlated with accelerometer data to determine the gravity level during solidification for any location of the sample. The thermal gradient and solidification rate were controlled independently. Samples run on the KC-135 aircraft exhibited bands of coarser graphite or of larger nodules usually corresponding to the regions solidified under low-g. Samples containing high phosphorous (used in order to determine the eutectic cell) exhibited larger eutectic cells in the low-g zone, followed by a band of coarser graphite.

  17. Tight coordination of aerial flight maneuvers and sonar call production in insectivorous bats.

    Science.gov (United States)

    Falk, Benjamin; Kasnadi, Joseph; Moss, Cynthia F

    2015-11-01

    Echolocating bats face the challenge of coordinating flight kinematics with the production of echolocation signals used to guide navigation. Previous studies of bat flight have focused on kinematics of fruit and nectar-feeding bats, often in wind tunnels with limited maneuvering, and without analysis of echolocation behavior. In this study, we engaged insectivorous big brown bats in a task requiring simultaneous turning and climbing flight, and used synchronized high-speed motion-tracking cameras and audio recordings to quantify the animals' coordination of wing kinematics and echolocation. Bats varied flight speed, turn rate, climb rate and wingbeat rate as they navigated around obstacles, and they adapted their sonar signals in patterning, duration and frequency in relation to the timing of flight maneuvers. We found that bats timed the emission of sonar calls with the upstroke phase of the wingbeat cycle in straight flight, and that this relationship changed when bats turned to navigate obstacles. We also characterized the unsteadiness of climbing and turning flight, as well as the relationship between speed and kinematic parameters. Adaptations in the bats' echolocation call frequency suggest changes in beam width and sonar field of view in relation to obstacles and flight behavior. By characterizing flight and sonar behaviors in an insectivorous bat species, we find evidence of exquisitely tight coordination of sensory and motor systems for obstacle navigation and insect capture.

  18. Chest physiotherapy on intracranial pressure of critically ill patients admitted to the intensive care unit: a systematic review.

    Science.gov (United States)

    Ferreira, Lucas Lima; Valenti, Vitor Engrácia; Vanderlei, Luiz Carlos Marques

    2013-01-01

    To analyze the outcomes of increased or decreased intracranial pressure and/or the decrease in cerebral perfusion pressure resulting from respiratory physiotherapy on critically ill patients admitted to the intensive care unit. Through a systematic review of the literature, clinical trials published between 2002 and 2012 were selected. The search involved the LILACS, SciELO, MedLine and PEDro databases using the keywords "physical therapy", "physiotherapy", "respiratory therapy" and "randomized controlled trials" combined with the keyword "intracranial pressure". In total, five studies, including a total of 164 patients between 25 and 65 years of age, reporting that respiratory physiotherapy maneuvers significantly increased intracranial pressure without changing the cerebral perfusion pressure were included. The articles addressed several techniques including vibration, vibrocompression, tapping, postural drainage, and the endotracheal aspiration maneuver. All patients required invasive mechanical ventilation. Respiratory physiotherapy leads to increased intracranial pressure. Studies suggest that there are no short-term hemodynamic or respiratory repercussions or changes in the cerebral perfusion pressure. However, none of the studies evaluated the clinical outcomes or ensured the safety of the maneuvers.

  19. Impact of Valsalva maneuver on central choroid, central macula, and disk fiber layer thickness among high myopic and hyperopic patients.

    Science.gov (United States)

    Kurultay-Ersan, Isil; Emre, Sinan

    2017-05-11

    To evaluate the alterations in mean central choroidal, central macular, and disk retinal nerve fiber layer (RNFL) thickness measured by optical coherence tomography (OCT) during Valsalva maneuver among patients with high refractive errors. A total of 60 high myopic (≥-6.0 D) and 50 high hyperopic (≥ + 3.0 D) eyes of 58 patients aged 19-65 years with visual acuity of 20/20 and without any ophthalmologic or systemic diseases were evaluated by OCT before and after the Valsalva maneuver. The choroidal thickness was measured with enhanced depth imaging OCT method. Central macular thickness, disk RNFL thickness, and axial length were also assessed. Mean choroidal thickness increased significantly from 275.0 ± 27.2 μm at rest to 279.8 ± 31.6 μm after Valsalva maneuver in high myopic patients, and from 308.2 ± 27.3 μm to 313.6 ± 28.5 μm in high hyperopic patients (pchoroidal thickness was noted with axial length (r = -0.509, pthickness was 242.9 ± 44.4 μm and 254.0 ± 22.8 μm, while mean disk RNFL thickness was 81.6 ± 12.4 μm and 98.4 ± 13.3 μm in high myopic and hyperopic patients, respectively. Valsalva maneuver was not associated with significant change in central macular or disk RNFL thickness. Significant association of Valsalva maneuver with an increase in choroidal thickness was noted among patients with high degree of myopia and hyperopia. Our findings emphasize the likelihood of increase in choroidal volume due to venous distension to be responsible for the increase observed in choroidal thickness after Valsalva maneuver.

  20. Determinants for a successful Sémont maneuver: an in-vitro study with a semicircular canal model

    Directory of Open Access Journals (Sweden)

    Dominik Obrist

    2016-09-01

    Full Text Available Objective: To evaluate the effect of time between the movements/steps, angle of body movements as well as the angular velocity of the maneuvers in an in-vitro model of a semicircular canal (SCC to improve the efficacy of the Sémont maneuver in benign paroxysmal positional vertigo (BPPV.Methods: Sémont maneuvers were performed on an in-vitro SCC model. Otoconia trajectories were captured by a video camera. The effects of time between the movements, angles of motion (0°, 10°, 20°, 30° below the horizontal line, different angular velocities (90, 135, 180°/s and otoconia size (36 and 50µm on the final position of the otoconia in the SCC were tested.Results: Without extension of the movements beyond the horizontal, the in-vitro experiments (with particles corresponding to 50 m diameter did not yield successful canalith repositioning. If the movements were extended by 20° beyond the horizontal position, Sémont maneuvers were successful with resting times of at least 16 s. For larger extension angles the required time decreased. However, for smaller particles (36 m the required time doubled. The angular maneuver velocity (tested between 90 and 180°/s did not have a major impact on the final position of the otoconia.Interpretation: The two primary determinants for success of the Sémont maneuver are the time between the movements and the extension of the movements beyond the horizontal. The time between the movements should be at least 45 s. Angles of 20° or more below horizontal line (so-called Sémont ++ should increase the success rate of SM.

  1. A multinomial-logit ordered-probit model for jointly analyzing crash avoidance maneuvers and crash severity

    DEFF Research Database (Denmark)

    Kaplan, Sigal; Prato, Carlo Giacomo

    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......Effective crash avoidance maneuvers in response to critical unexpected traffic events provide the opportunity to avoid crash occurrence and to minimize crash severity. The current study employs a joint multinomial-logit ordered-probit model (MNL-OR) for associating crash severity with drivers...

  2. Peer Pressure

    Science.gov (United States)

    ... who are unsure of themselves, new to the group, or inexperienced with peer pressure may also be more likely to give in. ... stand that makes you look uncool to your group. But these situations can be ... up to peer pressure, but it does take courage — yours: Listen to ...

  3. Hemi-hepatectomy in pediatric patients using two-surgeon technique and a liver hanging maneuver

    Institute of Scientific and Technical Information of China (English)

    Kyoko Mochizuki; Susumu Eguchi; Ryuichiro Hirose; Taiichiro Kosaka; Mitsuhisa Takatsuki; Takashi Kanematsu

    2011-01-01

    AIM: To evaluate the efficacy of the two-surgeon technique with the liver hanging maneuver (LHM) for hepatectomies in pediatric patients with hepatoblastoma. METHODS: Three pediatric patients with hepatoblastoma were enrolled in this study. Two underwent right hemi-hepatectomies and one underwent a left hemihepatectomy using the two-surgeon technique by means of saline-linked electric cautery (SLC) and the Cavitron Ultrasonic Surgical Aspirator (CUSA; Valleylab, Boulder, CO) and the LHM. RESULTS: The mean operative time during the parenchymal transections was 50 min and the mean blood loss was 235 g. There was no bile leakage from the cut surface after surgery. No macroscopic or microscopic-positive margins were observed in the hepatic transections. CONCLUSION: The two-surgeon technique using SLC and CUSA with the LHM is applicable to even pediatric patients with hepatoblastoma.

  4. No soy welferero: undocumented Latino laborers in the crosshairs of legitimation maneuvers.

    Science.gov (United States)

    Quesada, James

    2011-07-01

    California urban and agricultural centers rely heavily on Latino migrant laborers, regardless of their legal documented status. In the delivery of social services, and in the mass media, popular consciousness, and formal legal understandings and arrangements, Latino laborers are viewed as either legitimate voluntary low-wage workers or illegitimate undocumented workers not entitled to the same civil rights as US citizens. Their de facto second-class status becomes a central component of their social identity, with the structural conditions of their lives internalized, resulting in limited agency and poor social and health outcomes. The lived experience of structural vulnerability prefigures the actions and efforts of undocumented Latino contingent workers. In this article, the capacity for Latino laborers to maneuver and negotiate the travails of everyday life is explored.

  5. Behavior of the posterior semicircular canal after Dix-Hallpike maneuver

    Directory of Open Access Journals (Sweden)

    Francisco Carlos Zuma e Maia

    2016-05-01

    Full Text Available The objective of the present study is to analyze the quantitative vestibulo-ocular responses in a group of patients with benign paroxysmal positional vertigo (BPPV canalolithiasis and compare these data with the data of the tridimensional biomechanical model. This study was conducted on 70 patients that presented idiopathic posterior semicircular canal canalolithiasis. The diagnosis was obtained by Dix- Hallpike maneuvers recorded by videonystagmograph. The present study demonstrates that there is a significant correlation between the intensity of the nystagmus and its latency in cases of BPPV-idiopathic posterior semicircular canal canalolithiasis type. These findings are in agreement with those obtained in a tridimensional biomechanical model and are not related to the patients’ age.

  6. Comparison of two human-machine-interfaces for cooperative maneuver-based driving.

    Science.gov (United States)

    Franz, Benjamin; Kauer, Michaela; Blanke, Anton; Schreiber, Michael; Bruder, Ralph; Geyer, Sebastian

    2012-01-01

    In the project "Conduct-by-Wire" which is founded by the German Research Foundation (DFG) cooperative maneuver based driving is examined. In this paper two different input devices (gesture recognition and tactile touch display) are compared in a simulator study with 29 participants. It shows that the major advantage of the gesture recognition is that there is no need for the driver to take his gaze off the road. In contrast, the number of gazes at the tactile touch display is significantly higher. The major advantage of the tactile touch display is that no input errors occurred during the test drives. Conversely, the gesture recognition was significantly worse. Nevertheless, further work is needed to decide which input device is the best.

  7. ISAR Imaging of Maneuvering Targets Based on the Modified Discrete Polynomial-Phase Transform

    Directory of Open Access Journals (Sweden)

    Yong Wang

    2015-09-01

    Full Text Available Inverse synthetic aperture radar (ISAR imaging of a maneuvering target is a challenging task in the field of radar signal processing. The azimuth echo can be characterized as a multi-component polynomial phase signal (PPS after the translational compensation, and the high quality ISAR images can be obtained by the parameters estimation of it combined with the Range-Instantaneous-Doppler (RID technique. In this paper, a novel parameters estimation algorithm of the multi-component PPS with order three (cubic phase signal-CPS based on the modified discrete polynomial-phase transform (MDPT is proposed, and the corresponding new ISAR imaging algorithm is presented consequently. This algorithm is efficient and accurate to generate a focused ISAR image, and the results of real data demonstrate the effectiveness of it.

  8. 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...... seek to minimize their anticipated regret from their corrective actions. The model accounts for driver attributes and behavior, critical events that made the crash imminent, vehicle and road characteristics, and environmental conditions. Analyzed data are retrieved from the General Estimates System...... (GES) crash database for the period between 2005 and 2009. The predictive ability of the RRM-based model is slightly superior to its RUM-based counterpart, namely the multinomial logit model (MNL) model. The marginal effects predicted by the RRM-based model are greater than those predicted by the RUM-based...

  9. Anti-disturbance inverse optimal control for spacecraft position and attitude maneuvers with input saturation

    Directory of Open Access Journals (Sweden)

    Chutiphon Pukdeboon

    2016-05-01

    Full Text Available In this article, a new anti-disturbance inverse optimal translation and rotation control scheme for a rigid spacecraft with external disturbances and actuator constraint is presented. An inverse optimal controller with input saturations is designed to achieve asymptotic convergence to the desired translation and attitude and avoid the unwinding phenomenon. The derived optimal control law can minimize a given cost functional and guarantee the stability of the closed-loop system. Later, a new sliding mode disturbance observer is also proposed to compensate for the total disturbances. A rigorous Lyapunov analysis is employed to ensure the finite-time convergence of observer error dynamics. A numerical simulation of position and attitude maneuvers is given to verify the performance of the developed controller.

  10. Heart rate changes during the Valsalva maneuver in patients with isolated aortic insufficiency

    Directory of Open Access Journals (Sweden)

    Navarro A.E.

    1997-01-01

    Full Text Available To determine the possible relationship between left ventricular dilatation and heart rate changes provoked by the Valsalva maneuver (Valsalva ratio, we studied 9 patients with isolated chronic aortic insufficiency. Left ventricular systolic function was assessed by two-dimensional echocardiography and cardiac catheterization. All patients were asymptomatic (functional class I of the New York Heart Association. The left ventricular internal diameters and volumes were significantly increased in all patients. The asymptomatic patients had either normal or slightly depressed ejection fraction (EF>0.40. The Valsalva ratio of these asymptomatic patients showed no significant correlation with the left ventricular volumes or with the left ventricular ejection fraction. In other words, parasympathetic heart rate control, as expressed by the Valsalva ratio, was normal in the asymptomatic patients with left ventricular dilatation and preserved left ventricular ejection fraction. Therefore, left ventricular dilatation may not be the major mechanism responsible for the abnormal parasympathetic heart rate control of patients with acquired heart disease

  11. Finite-Time Control for Attitude Tracking Maneuver of Rigid Satellite

    Directory of Open Access Journals (Sweden)

    Mingyi Huo

    2014-01-01

    Full Text Available The problem of finite-time control for attitude tracking maneuver of a rigid spacecraft is investigated. External disturbance, unknown inertia parameters are addressed. As stepping stone, a sliding mode controller is designed. It requires the upper bound of the lumped uncertainty including disturbance and inertia matrix. However, this upper bound may not be easily obtained. Therefore, an adaptive sliding mode control law is then proposed to release that drawback. Adaptive technique is applied to estimate that bound. It is proved that the closed-loop attitude tracking system is finite-time stable. The tracking errors of the attitude and the angular velocity are asymptotically stabilized. Moreover, the upper bound on the lumped uncertainty can be exactly estimated in finite time. The attitude tracking performance with application of the control scheme is evaluated through a numerical example.

  12. Adaptive robust vibration control with input shaping as a flexible maneuver strategy

    Energy Technology Data Exchange (ETDEWEB)

    Sung, Yoon Gyeoung [KAERI, Taejon (Korea, Republic of)

    1999-11-01

    An adaptive robust control is presented for the vibration reduction of a flexible spacecraft by combining the input shaping technique with the sliding-mode control. The combined approach appears to be robust in the presence of a severe disturbance and an unknown parameter which will be estimated by on-line least-square method. As a maneuver strategy, it is found that a synthesized trajectory with a combination of low-frequency mode and rigid-body mode results in better performance and is more efficient than the traditional rigid-body trajectory alone which many researchers have employed. The feasibility of the vibration control approach is demonstrated by applying it to a benchmark problem in aerospace. For the applications of the proposed technique to realistic flexible spacecraft systems, several requirements are discussed such as mode stabilization and enormously large system order.

  13. Efficacy of Applying Postural Restrictions after Epley Maneuver in Patients with Benign Paroxysmal Positional Vertigo

    Directory of Open Access Journals (Sweden)

    Gholamali Dashti-Khavidaki

    2014-01-01

    Full Text Available Background: The purpose of this study was to determine the efficacy of applying postural restrictions after Epley maneuver on therapeutic success in patients with BPPV (Benign Paroxysmal Positional Vertigo. Materials and Methods: This randomized controlled clinical trial study was conducted in among 118 patients with BPPV at Khatam-al-Anbia hospital in Zahedan. First group treated with postural restrictions and the second with no restrictions. After one week the presence of BPPV examined and data were analyzed. Results: In first group 84.7% did not show symptoms of vertigo, as well as 45 patients in second group. Results did not show any significant difference between two groups. Conclusion: This study showed that instructions had no significant effect on the patients’ treatment outcomes.

  14. Behavior of the Posterior Semicircular Canal After Dix-Hallpike Maneuver

    Science.gov (United States)

    e Maia, Francisco Carlos Zuma; Albernaz, Pedro Luiz Mangabeira; Cal, Renato Valério

    2016-01-01

    The objective of the present study is to analyze the quantitative vestibulo-ocular responses in a group of patients with benign paroxysmal positional vertigo (BPPV) canalolithiasis and compare these data with the data of the tridimensional biomechanical model. This study was conducted on 70 patients that presented idiopathic posterior semicircular canal canalolithiasis. The diagnosis was obtained by Dix-Hallpike maneuvers recorded by videonystagmograph. The present study demonstrates that there is a significant correlation between the intensity of the nystagmus and its latency in cases of BPPV-idiopathic posterior semicircular canal canalolithiasis type. These findings are in agreement with those obtained in a tridimensional biomechanical model and are not related to the patients’ age. PMID:27588161

  15. Application of local Lyapunov exponents to maneuver design and navigation in the three-body problem

    Science.gov (United States)

    Anderson, Rodney L.; Lo, Martin W.; Born, George H.

    2003-01-01

    Dynamical systems theory has recently been employed to design trajectories within the three-body problem for several missions. This research has applied one stability technique, the calculation of local Lyapunov exponents, to such trajectories. Local Lyapunov exponents give an indication of the effects that perturbations or maneuvers will have on trajectories over a specified time. A numerical comparison of local Lyapunov exponents was first made with the distance random perturbations traveled from a nominal trajectory, and the local Lyapunov exponents were found to correspond well with the perturbations that caused the greatest deviation from the nominal. This would allow them to be used as an indicator of the points where it would be important to reduce navigation uncertainties.

  16. Integration of mechanism and control for large-angle slew maneuvers of flexible structures

    Science.gov (United States)

    Chew, Meng-Sang

    1991-01-01

    A rolling contact noncircular gear system is applied to assist a desired controller in the slewing of a flexible space structure. The varying gear ratio in cooperation with the controller results in lower feedback gains at the controller, as well as considerably reducing flexural vibrations of the space structure. The noncircular gears consist of a pair of convex noncircular cylinders with specially designed profiles that are synthesized in conjunction with the optimal controller gains for minimizing the flexural vibrations of flexible structure during a slew maneuver. Convexity of the cylindrical profiles for this noncircular gear device must be ensured to maintain rolling contact between the two cylinders. Simulations of slewing control tasks for two kinds of flexible space structures, such as a planar flexible beam and the planar articulated flexible beams, are presented.

  17. Management of benign paroxysmal positional vertigo with the canalith repositioning maneuver in the emergency department setting.

    Science.gov (United States)

    Burmeister, David B; Sacco, Regina; Rupp, Valerie

    2010-10-01

    Vertigo is a common clinical manifestation in the emergency department (ED). It is important for physicians to determine if the peripheral cause of vertigo is benign paroxysmal positional vertigo (BPPV), a disorder accounting for 20% of all vertigo cases. However, the Dix-Hallpike test--the standard for BPPV diagnosis--is not common in the ED setting. If no central origin of the vertigo is determined, patients in the ED are typically treated with benzodiazepine, antihistamine, or anticholinergic agents. Studies have shown that these pharmaceutical treatment options may not be the best for patients with BPPV. The authors describe a case of a 38-year-old woman who presented to the ED with complaints of severe, sudden-onset vertigo. The patient's BPPV was diagnosed by means of a Dix-Hallpike test and the patient was acutely treated in the ED with physical therapy using the canalith repositioning maneuver.

  18. The inspiratory maneuver: a simple method to assess the superficial lamina propria during endoscopy.

    Science.gov (United States)

    Sulica, Lucian; Behrman, Alison; Roark, Rick

    2005-09-01

    We describe a simple means of assessing the condition of the superficial lamina propria during endoscopy, which we use in our practice as an adjunct to careful stroboscopic examination. An intake of breath against partially adducted vocal folds serves to draw the mucosa inferomedially into the glottis, which reveals areas of diminished mobility, the relationship of mucosal lesions to deeper tissues of the vocal folds, and subtle submucosal lesions. This is possible because of the unique geometry of the glottis that renders the vector forces of airflow different at inspiration and expiration. Because the integrity of the superficial lamina propria is essential to healthy phonation, we have found the inspiratory maneuver useful across a wide variety of mucosal pathologic conditions.

  19. On Motion Planning for Point-to-Point Maneuvers for a Class of Sailing Vehicles

    Directory of Open Access Journals (Sweden)

    Lin Xiao

    2011-01-01

    Full Text Available Despite their interesting dynamic and controllability properties, sailing vehicles have not been much studied in the control community. In this paper, we investigate motion planning of such vehicles. Starting from a simple dynamic model of sailing vessels in one dimension, this paper first considers their associated controllability issues, with the so-called no-sailing zone as a starting point, and it links them with a motion planning strategy using two-point boundary value problems as the main mathematical tool. This perspective is then expanded to do point-to-point maneuvers of sailing vehicles in the plane, that is, automatic path generation combined with computation of control input profiles. Simulations are presented to illustrate the potential of the approach.

  20. Step-by-step isolated resection of segment 1 of the liver using the hanging maneuver.

    Science.gov (United States)

    López-Andújar, Rafael; Montalvá, Eva; Bruna, Marcos; Jiménez-Fuertes, Montiel; Moya, Angel; Pareja, Eugenia; Mir, Jose

    2009-09-01

    The caudate lobe can be the origin of primary liver tumours or the sole site of liver metastases. This lobe is anatomically divided into 3 parts: Spiegel's lobe (Couinaud's segment 1), paracaval portion (Couinaud's segment 9), and the caudate process. In this series of 4 cases, we provide a step-by-step description of a surgical technique variation that can be applied to resections of lesions localized in segment 1. We believe that other than size, lesion removal in this hepatic anatomic area, which is difficult to perform, can be done more easily using this new approach because it requires minimal mobilization without unnecessary parenchyma transection of other liver parts. Therefore, it reduces the risk of lesions in the inferior vena cava and the middle hepatic vein and respects adequate margins without the use of clamping maneuvers and in an acceptable surgical time.