scholarly journals A Test-Bed For Measuring UAS Servo Reliability

Aerospace ◽  
2019 ◽  
Vol 6 (9) ◽  
pp. 96
Author(s):  
AbdElRahman ElSaid ◽  
Daniel Adjekum ◽  
John Nordlie ◽  
Fatima El Jamiy
Keyword(s):  
Performance Standards ◽  
Baseline Period ◽  
Base Line ◽  
Test Bed ◽  
Real World Data ◽  
Safety Hazard ◽  
Flight Operations ◽  
Component Test ◽  
The Mean ◽  
Commercial Off The Shelf

Extant literature suggests minimal research on the reliability of Commercial off-the-shelf (COTS) components used in fabricating non-military Unmanned Aerial System (UAS). Stochastic failures of components during operational cycles over time poses a safety hazard to flight operations. The purpose of the study was to critically assess the operational performance standards (reliability) of a laboratory designed UAS component test-bed operated using real-world data collected from a Boeing Scan Eagle® UAS aileron servo unit via a flight data recorder. The study hypothesized that the test-bed’s reliability, in terms of a measured encoder output of commanded servo positions, will not be significantly different after double and triple periods of time for continuous operations compared to a base-line mean position. Results suggested that test-bed operated within reliability criteria for a baseline period but there were significant differences in the mean of the reliability after the operational cycles were doubled and tripled in time. This study adds to paucity of extant research on UAS COTS reliability and recommends further studies on reliability of other small UAS components within periods of time.

scholarly journals AB0393 EFFICACY OF HYDROXYCHLOROQUINE FOR LUPUS NEPHRITIS IN MAINTENANCE PHASE

2020 ◽  
Vol 79 (Suppl 1) ◽  
pp. 1496.2-1496
Author(s):  
M. Watanabe ◽  
Y. Haji ◽  
M. Kato ◽  
T. Ito ◽  
Y. Banno ◽  
...  
Keyword(s):  
Lupus Nephritis ◽  
Lupus Erythematosus ◽  
Therapeutic Option ◽  
Maintenance Phase ◽  
Base Line ◽  
Prednisolone Dose ◽  
Daily Urine ◽  
Group A ◽  
The Mean ◽  
Group B

Background:Hydroxychloroquine (HCQ) is an essential drug for systemic lupus erythematosus. But in Japan, chloroquine and HCQ remain unavailable until mid 2015 because of a series of lawsuits about its retinal toxicity in the 1970s. There is insufficient knowledge regarding renal protective effect of HCQ.Objectives:We aimed to investigate its efficacy of adding HCQ for Lupus nephritis (LN) as a maintenance-phase therapy.Methods:We conducted an observational retrospective cohort study included patients with LN (n=42) in maintenance-phase in Japan. We reviewed medical records of LN patients aged > 18 years who were initiated HCQ from May 2015 to May 2018. Maintenance phase was defined as stabilization in serum creatinine and urinary segment after induction therapy and who achieved complete or partial remission. The annual change of proteinuria was compared between patients on HCQ who have proteinuria (>0.5g/gCr) or not. Other outcome measures were disease flare, dose of steroids, renal and immunologic features.Results:A total of 42 patients were analyzed and allocated to two groups based on their amount of daily urine protein level: HCQ with proteinuria as group A (>0.5g/gCr, n=14) and HCQ without proteinuria as group B(≦0.5g/gCr, n=28). Both groups were comparable, with mean (SD) age of 36.1 (12.9) years and 37.5 (13.8), female 78.6% and 92.9% in each group, mean (SD) disease duration until HCQ of 3.5 (3.25) and 3.3 (2.9) years in group A and group B, with prednisolone dose at base line of 10.3 (7.1) mg and 7.9 (4.4) mg, respectively. The mean (SD) proteinuria at base line was 1.38 (1.11) g/gCr in group A and 0.20 (0.09) g/gCr in group B and after 12 months, proteinuria decreased in group A (-1.34 g/gCr in group A vs +0.03 g/gCr in group B; p<.001;95% CI,0.305-0.736). No relapse was experienced in group A during the study period.Conclusion:In patients with clinically stable LN but with proteinuria, hydroxychloroquine is a good therapeutic option for achievement of complete remission.Disclosure of Interests:None declared

Evaluating the Effect of Three-Dimensional Visualization on Force Application and Performance Time during Robotics-Assisted Mitral Valve Repair

2013 ◽  
Vol 8 (3) ◽  
pp. 199-205 ◽  
Author(s):  
Maria E. Currie ◽  
Ana Luisa Trejos ◽  
Reiza Rayman ◽  
Michael W.A. Chu ◽  
Rajni Patel ◽  
...  
Keyword(s):  
Cardiac Surgery ◽  
Mitral Valve ◽  
Haptic Feedback ◽  
3D Visualization ◽  
Three Dimensional ◽  
Test Bed ◽  
Mitral Valve Annuloplasty ◽  
Significant Difference ◽  
The Mean ◽  
Mean Time

Objective The purpose of this study was to determine the effect of three-dimensional (3D) binocular, stereoscopic, and two-dimensional (2D) monocular visualization on robotics-assisted mitral valve annuloplasty versus conventional techniques in an ex vivo animal model. In addition, we sought to determine whether these effects were consistent between novices and experts in robotics-assisted cardiac surgery. Methods A cardiac surgery test-bed was constructed to measure forces applied during mitral valve annuloplasty. Sutures were passed through the porcine mitral valve annulus by the participants with different levels of experience in robotics-assisted surgery and tied in place using both robotics-assisted and conventional surgery techniques. Results The mean time for both the experts and the novices using 3D visualization was significantly less than that required using 2D vision (P < 0.001). However, there was no significant difference in the maximum force applied by the novices to the mitral valve during suturing (P = 0.7) and suture tying (P = 0.6) using either 2D or 3D visualization. The mean time required and forces applied by both the experts and the novices were significantly less using the conventional surgical technique than when using the robotic system with either 2D or 3D vision (P < 0.001). Conclusions Despite high-quality binocular images, both the experts and the novices applied significantly more force to the cardiac tissue during 3D robotics-assisted mitral valve annuloplasty than during conventional open mitral valve annuloplasty. This finding suggests that 3D visualization does not fully compensate for the absence of haptic feedback in robotics-assisted cardiac surgery.

scholarly journals In-flight wing deformation measurements on a glider

2016 ◽  
Vol 120 (1234) ◽  
pp. 1917-1931 ◽  
Author(s):  
J. Bakunowicz ◽  
R. Meyer
Keyword(s):  
Measurement Techniques ◽  
Flight Test ◽  
Lessons Learned ◽  
Correlation Technique ◽  
Test Bed ◽  
Flight Testing ◽  
Flight Operations ◽  
Flight Measurement ◽  
Industrial Level ◽  
Deformation Measurements

ABSTRACTFlight testing is both vital for collecting data for aeronautic research and at the same time fascinating for its contributors. Taking a glider as a versatile test bed example, this paper presents a transnational measurement campaign within the framework of a collaborative project funded by the European Commission. This project Advanced In-Flight Measurement Techniques 2 (AIM²) is a follow-up of Advanced In-Flight Measurement Techniques (AIM) and dedicated to developing and enhancing promising optical metrology for various flight test applications up to an industrial level.The Image Pattern Correlation Technique (IPCT) and infrared thermography (IRT) are two of these modern non-intrusive measurement methods that were further developed and applied to the glider test bed within the scope of AIM². Focusing on optical deformation measurements with IPCT the experimental setup, the flight testing and results are summarily discussed. Gliders are not commonly used flight test platforms, which is why this contribution concludes with some lessons learned in general and especially related to the presented application. The experience to be shared with the flight testing community addresses equipment preparation, data collection and processing as well as how to meet official requirements and perform test flight operations in a dense controlled airspace.

scholarly journals A Secured Load Mitigation and Distribution Scheme for Securing SIP Server

2017 ◽  
Vol 2017 ◽  
pp. 1-14 ◽  
Author(s):  
Vennila Ganesan ◽  
Manikandan MSK
Keyword(s):  
Load Distribution ◽  
Test Bed ◽  
Heavy Load ◽  
Server Selection ◽  
Distribution Scheme ◽  
The Mean ◽  
Sip Server ◽  
Second Tier ◽  
Termination Time

Managing the performance of the Session Initiation Protocol (SIP) server under heavy load conditions is a critical task in a Voice over Internet Protocol (VoIP) network. In this paper, a two-tier model is proposed for the security, load mitigation, and distribution issues of the SIP server. In the first tier, the proposed handler segregates and drops the malicious traffic. The second tier provides a uniform load of distribution, using the least session termination time (LSTT) algorithm. Besides, the mean session termination time is minimized by reducing the waiting time of the SIP messages. Efficiency of the LSTT algorithm is evaluated through the experimental test bed by considering with and without a handler. The experimental results establish that the proposed two-tier model improves the throughput and the CPU utilization. It also reduces the response time and error rate while preserving the quality of multimedia session delivery. This two-tier model provides robust security, dynamic load distribution, appropriate server selection, and session synchronization.

Vasomotion of basilar arteries in vivo

1990 ◽  
Vol 258 (6) ◽  
pp. H1829-H1834 ◽  
Author(s):  
K. Fujii ◽  
D. D. Heistad ◽  
F. M. Faraci
Keyword(s):  
Moderate Hypertension ◽  
Vessel Diameter ◽  
Base Line ◽  
Large Artery ◽  
Cranial Window ◽  
Basilar Arteries ◽  
The Mean ◽  
Rhythmic Change ◽  
The Brain

Vasomotion is a rhythmic change in vascular caliber that has been described in vivo mainly in peripheral arterioles. In this study, we have characterized vasomotion in a large artery of the brain in vivo. In anesthetized rats, spontaneous vasomotion was observed in 38 of 47 basilar arteries visualized through a cranial window. Base-line arterial diameter was 259 +/- 9 (means +/- SE) microns. Under control conditions, the frequency of vasomotion was 4.8 +/- 0.2 cycles/min, and the amplitude was 19 +/- 2% of the mean diameter. Vasomotion usually occurred simultaneously along the entire length of the vessel, but in some arteries it propagated in either direction. Moderate hypertension (phenylephrine) or vasoconstriction induced by topical application of serotonin, vasopressin, or the thromboxane analogue U 46619 increased the frequency of vasomotion. Moderate hypotension or vasodilation induced by nitroglycerin, adenosine, or acetylcholine decreased the frequency. Marked hypertension, hypotension, or vasodilatation abolished vasomotion. Thus vasomotion of the basilar artery in vivo 1) is common and of relatively large amplitude, 2) does not seem to be driven by a single pacemaker, and 3) is dependent on vessel diameter or vasomotor tone.

scholarly journals Clinical, epidemiological and autoimmune associations in childhood vitiligo in Qatar

2020 ◽  
Vol 6 (2) ◽  
pp. 151
Author(s):  
Haya Al Mannai ◽  
Mohamed Allam ◽  
Hassan Riad
Keyword(s):  
Family History ◽  
Autoimmune Diseases ◽  
Age Of Onset ◽  
Positive Family History ◽  
Thyroid Peroxidase ◽  
Base Line ◽  
Adult Onset ◽  
Prognostic Features ◽  
History Of ◽  
The Mean

<p class="abstract"><strong>Background:</strong> Childhood vitiligo although clinically similar to adult onset vitiligo but it has distinct clinical, epidemiological and prognostic features compared to adult onset vitiligo.</p><p class="abstract"><strong>Methods:</strong> This is a retrospective study that was carried out on 85 pediatric patients up to age of 18 years old with the diagnosis of vitiligo, where the clinical and epidemiological data  including clinical type of vitiligo, family history of autoimmune diseases like thyroid disorders and diabetes mellitus and laboratory results including anti-thyroid peroxidase antibodies (anti-TPO antibodies), anti-parietal cell antibodies, antinuclear antibodies (ANA), Vitamin D and Vitamin B12 were retrieved from the files of these patients.<strong></strong></p><p class="abstract"><strong>Results:</strong> The mean age of the children affected by vitiligo was 10.4 years, the mean age of onset of vitiligo was 5.4 years, 54 (63.5%) percent were girls and 31 (36.5%) were boys. A positive family history of vitiligo was found in 44.7% of the participants, family history of DM was found in 64.7% of patients and family history of thyroid disease was found in 32.9% of the participants. The prevalence of thyroid autoimmunity was found to be in 22.4% of total participants.</p><p class="abstract"><strong>Conclusions:</strong> Childhood vitiligo has distinct clinical features, more common family history for autoimmune diseases and thyroid autoantibodies rather than overt clinical diseases, which raise the necessity to perform a routine initial immunological and thyroid screening in children with vitiligo and to repeat them at annual bases if there were abnormal values at base line or strong family history.</p>

Altered osmotic thresholds for vasopressin secretion and thirst in human pregnancy

1984 ◽  
Vol 246 (1) ◽  
pp. F105-F109 ◽  
Author(s):  
J. M. Davison ◽  
E. A. Gilmore ◽  
J. Durr ◽  
G. L. Robertson ◽  
M. D. Lindheimer
Keyword(s):  
Plasma Osmolality ◽  
Late Pregnancy ◽  
Base Line ◽  
Urinary Volume ◽  
Human Pregnancy ◽  
Slow Infusion ◽  
Vasopressin Secretion ◽  
The Subject ◽  
The Mean ◽  
Plasma Arginine

Osmoregulation was studied in eight women during late pregnancy and again 8-10 wk postpartum. Base-line plasma osmolality (Posmol) was significantly lower during (280.9 +/- 2.1 mosmol/kg, SD) than after (289.4 +/- 2.1 mosmol/kg) pregnancy yet 24-h urinary volume and plasma arginine vasopressin (PAVP) measured in vasopressinase-inactivated blood was similar in both groups (pregnancy, 1.39 +/- 0.56 pg/ml; postpartum, 1.25 +/- 0.62 pg/ml). After 12 h of dehydration PAVP rose similarly and significantly both during (2.25 +/- 0.81 pg/ml) and after (2.89 +/- 1.19 pg/ml) gestation, and Uosmol was similar on both occasions (pregnancy, 779 +/- 121 mosmol/kg; postpartum, 784 +/- 102 mosmol/kg). When Posmol was increased by the slow infusion of 5% saline PAVP increased as soon as body tonicity did both during and after pregnancy. PAVP correlated significantly with Posmol in each subject (range of r, 0.75-0.99) and the mean regression lines [pregnancy, PAVP = 0.32 (Posmol; -279), r = 0.79; postpartum, PAVP = 0.38 (Posmol, -285), r = 0.86] demonstrated that the apparent osmotic threshold for AVP secretion was 6 mosmol/kg lower during than after gestation. Similarly the Posmol at which the subject experienced a conscious desire to drink was lower in pregnant (287 +/- 1.6 mosmol/kg) compared with postpartum subjects (298 +/- 2.0 mosmol/kg; P less than 0.001). These data demonstrate decreased osmotic thresholds for AVP release and thirst during human pregnancy and explain why gravidas can maintain their new lower Posmol within narrow limits.

Pulmonary impedance in dogs measured by forced random noise with a retrograde catheter

1982 ◽  
Vol 52 (3) ◽  
pp. 725-733 ◽  
Author(s):  
J. M. Fullton ◽  
D. A. Hayes ◽  
R. L. Pimmel
Keyword(s):  
Endotracheal Tube ◽  
Airway Resistance ◽  
Random Noise ◽  
Peripheral Resistance ◽  
Base Line ◽  
The Mean ◽  
The Difference ◽  
Central Airway

Retrograde catheter and forced random noise techniques were combined to study the distribution of resistance and compliance in dogs following the inhalation of aerosols containing 2.5 and 5.0 mg/ml of histamine. Mean base-line peripheral resistance was 0.367 cmH2O . l'1 . s, agreeing with previous estimates. After correction for the endotracheal tube, the mean central airway resistance was 0.040 cmH2O . l'1 . s, considerably lower than previous estimates. This discrepancy was attributed to an overcorrection for the endotracheal tube resistance. The lower histamine dose caused a substantial increase in peripheral resistance, a relatively small increase in central resistance, and substantial decreases in total and peripheral compliance. After the higher histamine dose, changes in peripheral resistance and both compliances were similar to those obtained with the lower dose; however, the increase in central resistance was much larger than at the lower dose. The difference between total and peripheral compliance yielded estimates of airway compliance of 0.00306 l/cmH2O before and 0.00104 l/cmH2O after 2.5 mg/ml of histamine.

Time course of the bronchoconstriction induced by inhaled histamine and methacholine

1983 ◽  
Vol 54 (3) ◽  
pp. 821-826 ◽  
Author(s):  
A. Cartier ◽  
J. L. Malo ◽  
P. Begin ◽  
M. Sestier ◽  
R. R. Martin
Keyword(s):  
Flow Resistance ◽  
Time Course ◽  
Recovery Phase ◽  
Base Line ◽  
Prolonged Action ◽  
Initial Value ◽  
Pulmonary Flow ◽  
The Mean

Eleven asthmatic subjects inhaled doubling concentrations of histamine until a near sixfold increase in total pulmonary flow resistance had been reached. This last concentration (C6) of histamine and methacholine was administered on two subsequent separate visits. Specific lung conductance (sGL) dropped to 18.6 +/- 7.9 (SD) and 19.1 +/- 10.3% of initial value after histamine and methacholine, respectively (NS). Whereas the peak action occurred in a similar interval (1–4 min), the mean duration of the subsequent plateau, defined as values of sGL within 20% of the maximum fall was 16.8 +/- 9.8 min for histamine and 74.6 +/- 53.7 min for methacholine (P less than 0.01). The recovery phase from the end of the plateau to base line lasted 25.5 +/- 14.4 min for histamine and 56.7 +/- 38.3 min for methacholine (P less than 0.01). The duration of plateau and recovery phases were not linked with base-line sGL, maximum fall in sGL, or C6. We conclude that for the same induced bronchoconstriction methacholine has a more prolonged action than histamine.

Corrigenda for vol. 251, p. E209

1987 ◽  
Vol 252 (1) ◽  
pp. 1-b-1
Keyword(s):  
Statistical Analyses ◽  
Glucose Turnover ◽  
Base Line ◽  
The Mean ◽  
Response To Exercise

Pages E209–E214: Dan M. Cooper, David H. Wasserman, Mladen Vranic, and Karl Wasserman. “Glucose turnover in response to exercise during high- and low-FiOO2, breathing in man.” Page E211: results, the mean base-line value of Rd during hypoxia was 2.84 ± 1.19 mg·min-1·kg–1 rather than the reported 3.16 ± 1.39 mg·min-1·kg-1, and during hyperoxia the mean base-line value of Rd was 3.79 ± 1.11 mg·min-1·kg-1 rather than the reported 3.52 ± 1.15 mg·min-1·kg-1. The values are correct for all of the published statistical analyses, percent changes, Figs. 1–5, and “Abstract.”

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