The Influence of the TCS on the Circumferential Mode Distribution in the Inlet of a Fanrig (UFFA)

2012 ◽  
Author(s):  
Wolfram Köhler
Keyword(s):  
Control Device ◽  
Mode Analysis ◽  
Test Bed ◽  
Turbulence Control ◽  
Turbulence Structures ◽  
Mode Detection ◽  
Significant Difference ◽  
Full Picture ◽  
Rotor Stator Interaction ◽  
Static Conditions

Sophisticated noise testing of an aero engine fan on a static indoor test bed requires special arrangements to produce reliable data. One of these items used to improve the measured data quality is the TCS (turbulence control screen) (also called ICD, inlet control device). The TCS reduces the disturbances in the inflow resulting from the static conditions. In this way the results are comparable to flight tests with a more uniform inflow. The effects of the TCS with regards to turbulence structures in general are well studied. To get the full picture of the acoustic behaviour of the TCS the mode generation needs to be investigated and understood. This paper gives an overview of the inlet mode analysis performed for the UFFA (Universal Fan Facility for Acoustics). As expected the noise characteristic shows a significant difference especially upstream of the fan whether measurements were carried out with or without TCS. To get a better understanding of what is happening, the circumferential mode distribution in the inlet was measured with a CMD (circumferential mode detection) ring and the measurements were analysed with an algorithm based on the information published by the NLR (National Aerospace Laboratory of the Netherlands). The results show, that the inflow has a considerable influence on the spinning modes caused by the rotor-stator interaction (RSI) described by Tyler-Sofrin as well as on the rotor-alone noise. The circumferential modes generated by the rotor-stator interaction are significantly reduced by an unsteady nonuniform inflow while the rotor self noise is increased through turbulence-rotor interaction.

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 The Effect of Sonophoresis on Topical Anesthesia: A Pilot Project

2013 ◽  
Vol 60 (2) ◽  
pp. 37-41 ◽  
Author(s):  
Joseph L. Packer ◽  
Barry Krall ◽  
Ali Makki ◽  
Mahmoud Torabinejad
Keyword(s):  
Stratum Corneum ◽  
Pain Perception ◽  
Pilot Project ◽  
Control Device ◽  
Topical Anesthesia ◽  
Needle Puncture ◽  
Topical Anesthetic ◽  
Novel Device ◽  
Needle Penetration ◽  
Significant Difference

Abstract The dental anesthesia sonophoresis device (DASD) is a novel device that is intended to reduce the discomfort associated with intraoral mucosa needle puncture. The DASD produces ultrasonic energy that provides a sonophoretic effect on the oral mucosa, generating microchannels through the lipids between the keratinized cells that make up the stratum corneum. Once the topical anesthetic has permeated the stratum corneum, it quickly diffuses through the soft tissue, desensitizing the nerve endings and reducing the perception of pain caused by needle penetration. The aim of this study is to evaluate whether topical anesthesia applied using the DASD will reduce the discomfort of the needle puncture when compared to the control device. A split-mouth model, using 50 healthy subjects with puncture site at the maxillary canine vestibule, was used for this study. Subjects received a needle puncture on both sides of the mouth. Prior to the needle puncture, there was randomized application of 5% lidocaine with the DASD and a control device. Subjects rated their discomfort after needle punctures utilizing the visual analog scale pain scoring system. There was no statistically significant difference in the pain perception using the DASD versus the control device.

scholarly journals Performance, Movement, Posture, and Perceived Discomfort in Active vs. Static Seating

2019 ◽  
Vol 63 (1) ◽  
pp. 1154-1158
Author(s):  
Jeremy D. Faulk ◽  
Cameron C. McKee ◽  
Heather Bazille ◽  
Michael Brigham ◽  
Jasmine Daniel ◽  
...  
Keyword(s):  
Task Performance ◽  
Motor Task ◽  
Fine Motor ◽  
Future Research ◽  
Trunk Movement ◽  
Significant Difference ◽  
Within Subjects ◽  
Computer Based ◽  
Preliminary Study ◽  
Static Conditions

Active seating designs may enable users to move more frequently, thereby decreasing physiological risks associated with a sedentary lifestyle. In this preliminary study, two active seating designs (QOR360, Ariel; QOR360, Newton) were compared to a static chair (Herman Miller, Aeron) to understand how active vs. static seating may affect task performance, movement, posture, and perceived discomfort. This within-subjects experiment involved n = 11 student participants who sat upon each of the three chairs for 20 minutes while performing a series of computer-based tasks. Participants showed increased trunk movement while also reporting higher levels of perceived discomfort in the two active chair conditions. There was no significant difference in either posture or fine motor task performance between the active and static conditions. Future research may benefit from additional physiological measurements along with a wider variety of tasks that require seated users to make postural adjustments.

Effects of Verbal and Verbal-Motor Responses on Meter Conceptualization in Third-, Fourth-, and Fifth-Grade Children

1992 ◽  
Vol 40 (3) ◽  
pp. 216-224
Author(s):  
Russell L. Jones
Keyword(s):  
Grade Level ◽  
Motor Response ◽  
Response Mode ◽  
Verbal Response ◽  
Mode Analysis ◽  
Fifth Grade ◽  
Verbal Responses ◽  
Fifth Grade Students ◽  
Significant Difference ◽  
Main Effects

My purpose was to determine the effects of grade level and response mode on the ability of second-semester third-, fourth-, and fifth-grade students to identify and conceptualize meter in music. Thirty-six subjects at each grade level were divided into two response-mode groups. Subjects in the verbal-motor response groups were asked to respond verbally and to use specific conducting motions; verbal-response-mode subjects used only verbal responses. A two-way analysis of variance indicated that both main effects of grade level and response mode were significant, indicating that scores on the meter-concept test improved with increasing age and as a result of using the verbal-motor response mode. Analysis of simple effects indicated that fourth- and fifth-grade subjects in the verbal-motor response mode were superior to fourth- and fifth-grade subjects in the verbal response mode; mode of response, however, did not result in a significant difference in third-grade subjects.

scholarly journals Biomechanics in an Incomplete Versus Complete Supraspinatus Tear: A Cadaveric Study

2020 ◽  
Vol 8 (12) ◽  
pp. 232596712096447
Author(s):  
Danil Rybalko ◽  
Aimee Bobko ◽  
Farid Amirouche ◽  
Dmitriy Peresada ◽  
Awais Hussain ◽  
...  
Keyword(s):  
Rotator Cuff ◽  
Humeral Head ◽  
Rotator Cuff Tears ◽  
Vertical Position ◽  
Study Objective ◽  
Supraspinatus Tear ◽  
Complete Tear ◽  
Significant Difference ◽  
Static Conditions ◽  
Biomechanical Comparison

Background: Degenerative and traumatic changes to the rotator cuff can result in massive and irreparable rotator cuff tears (RCTs). Purpose/Hypothesis: The study objective was to conduct a biomechanical comparison between a small, incomplete RCT and a large, complete RCT. We hypothesized that the incomplete supraspinatus (SS) tear would lead to an incremental loss of abduction force and preserve vertical position of the humeral head, while a complete SS tear would cause superior humeral migration, decrease functional deltoid abduction force, and increase passive range of motion (ROM). Study Design: Controlled laboratory study. Methods: Six cadaveric shoulders were evaluated using a custom testing apparatus. Each shoulder was subjected to 3 conditions: (1) intact/control, (2) 50%, full-thickness, incomplete SS tear, and (3) 100%, complete SS tear. Deltoid abduction force, superior humeral head migration, and passive ROM were measured in static conditions at 0°, 30°, and 60° of glenohumeral abduction, respectively. Results: The intact SS resulted in a mean deltoid abduction force of 2.5, 3.3, and 3.8 N at 0°, 30°, and 60° of abduction, respectively. Compared with the intact shoulder, there was no significant difference in mean abduction force seen in the incomplete tear, while the force was significantly decreased by 52% at 30° of abduction in the complete tear ( P = .009). Compared with the incomplete tear, there were significant decreases in abduction force seen in the complete tear, by 33% and 48% (0.9 N and 1.1 N) at 0° and 30° of abduction, respectively ( P = .04 and .004). The intact configuration experienced a mean superior humeral head migration of 1.5, 1.4, and 1.1 mm at 0°, 30°, and 60° of abduction, respectively. The complete tear resulted in a superior migration of 3.0 and 4.4 mm greater than the intact configuration at 0° and 30° of abduction, respectively ( P = .001). There was a 5° and 10° increase in abduction ROM with 50% and 100% tears, respectively ( P = .003 and .03). Conclusion: An incomplete SS tear does not significantly alter the biomechanics of the shoulder, while a large, complete SS tear leads to a significant superior humeral migration, a decreased deltoid abduction force, and a mild increase in passive ROM. Clinical Relevance: Our findings demonstrate the effects of large SS tears on key biomechanical parameters, as they progress from partial tears.

The Electrical Properties and Changes on the Substrates of Microbial Fuel Cells Using Excess Sludge

2014 ◽  
Vol 535 ◽  
pp. 141-144
Author(s):  
Xiao Qin Zhao ◽  
Xiao Jie Sun
Keyword(s):  
Fuel Cells ◽  
Anaerobic Digestion ◽  
Microbial Fuel Cells ◽  
Control Device ◽  
Anaerobic Sludge ◽  
Excess Sludge ◽  
Test Volume ◽  
Significant Difference ◽  
Nacl Concentration ◽  
Anode Area

A single-chamber and membrane-less microbial fuel cells (MFC) was successfully started up using anaerobic sludge as inoculums without any nutrient elements for 20 d. Under 30 °C, excess sludge SS was about 21000 mg·L-1, anode area for 31.4 cm2and in 200 mM NaCl concentration agent conditions experiment MFC, while the control device (CD) directly with original sludge anaerobic digestion. The electricity generation of microbial fuel cell and the contrast of substrate changes were investigated. The results show that obtained maximum voltage is 597.3 mV, pH in MFC is slightly higher than in contrast test. Volume reduction in MFC is larger than the controls. Reducing sugar in MFC is lower than that in CDs. Proteins increase at first and then decrease, finally there is no significant difference in both of MFC and CD. Key words: Microbial Fuel Cells, Excess Sludge, Anaerobic Digestion, Reutilization

scholarly journals Two-temperature dual-phase-lags theory in a thermoelastic solid half-space due to an inclined load

2016 ◽  
Vol 7 (2) ◽  
pp. 179-187
Author(s):  
Ashraf M. Zenkour ◽  
Ahmed E. Abouelregal ◽  
Khaled A. Alnefaie ◽  
Nidal H. Abu-Hamdeh ◽  
Abdulmalik A. Aljinaidi ◽  
...  
Keyword(s):  
Half Space ◽  
Mode Analysis ◽  
Dual Phase ◽  
Horizontal Distance ◽  
Inclined Load ◽  
Special Cases ◽  
Wide Range ◽  
Significant Difference ◽  
Phase Lags ◽  
Two Temperature

Abstract. This article addresses the thermoelastic interaction due to inclined load on a homogeneous isotropic half-space in context of two-temperature generalized theory of thermoelasticity with dual-phase-lags. It is assumed that the inclined load is a linear combination of both normal and tangential loads. The governing equations are solved by using the normal mode analysis. The variations of the displacement, stress, conductive temperature, and thermodynamic temperature distributions with the horizontal distance have been shown graphically. Results of some earlier workers have also been deduced from the present investigation as special cases. Some comparisons are graphically presented to estimate the effects of the two-temperature parameter, the dual-phase-lags parameters and the inclination angle. It is noticed that there is a significant difference in the values of the studied fields for different value of the angle of inclination. The method presented here maybe applicable to a wide range of problems in thermodynamics and thermoelasticity.

scholarly journals Bonding of Core Build-Up Composites with Glass Fiber-Reinforced Posts

2019 ◽  
Vol 7 (4) ◽  
pp. 105 ◽  
Author(s):  
Margarita Fragkouli ◽  
Ioannis Tzoutzas ◽  
George Eliades
Keyword(s):  
Glass Fiber ◽  
Tensile Force ◽  
Core Material ◽  
Mode Analysis ◽  
Fiber Reinforced ◽  
The Core ◽  
Glass Fiber Reinforced ◽  
Significant Difference ◽  
Failure Mode Analysis ◽  
Material Fracture

The purpose of this study was to investigate the bonding capacity of composite core build-up materials with prefabricated glass fiber-reinforced posts possessing different coronal morphologies. Five post types (Archimede Line (ARL), Fibrekleer (FBK), Glassix (GLX), Matrix Plus (MTP), and ParaPost White (PRW) and three core build-up materials (ClearfilPhoto Core (CPC), ClearfilDC Core (CDC), ClearfilNew Bond (CNB) of different curing modes (light-, self-, dual-cured respectively) were selected. The coronal part was embedded in the core build-up materials and the specimens were loaded under tensile force up to failure. The reliability (β) and characteristic life (σο, in Ν) of the debonding force were evaluated by Weibull statistics and the debonded specimens were subjected to failure mode analysis. The results showed that ARL, MPT posts were the most and GLX the least retentive, despite the core build-up material used. CPC provided the highest retention with four posts (FBK, GLX, MTP, and PRW), without statistically significant differences from CDC in two (FBK and MTP) and CNB in one (PRW). CPC and CDC were the most reliable core materials for two posts (ARL and PRW), with no statistically significant difference from CNB in three (FBK, GLX, and MTP). GLX and PRW demonstrated the highest (93%) incidence of post detachment from core, whereas FBK demonstrated the highest percentage of core material fracture, with most fractures occurring in CDC (57%). Post fractures were most prominent in MTP when combined with CNB. The presence of specific coronal retentive features did not essentially ensure increased strength with the core material, due to their delamination.

Abstract P561: Efficacy of Beveled Tip Aspiration Catheter in Mechanical Thrombectomy for Acute Ischemic Stroke

Stroke ◽  
2021 ◽  
Vol 52 (Suppl_1) ◽  
Author(s):  
Jan Vargas Machaj ◽  
Jonathan Blalock ◽  
Anand Venkatraman ◽  
Vania Anagnostakou ◽  
Robert King ◽  
...  
Keyword(s):  
Ischemic Stroke ◽  
Mechanical Thrombectomy ◽  
Control Device ◽  
P Value ◽  
Patient Demographics ◽  
Improved Outcomes ◽  
Significant Difference ◽  
Catheter Tip ◽  
Thrombectomy Device ◽  
Iv Tpa

Introduction: The ADAPT technique uses large bore aspiration catheters for mechanical thrombectomy. Several aspiration catheters are now available. We report a bench-top exploration of a beveled-tip catheter, and our experience in treating large vessel occlusions using next-generation aspiration catheters. Methods: Twenty experiments were conducted with either a Sofia Plus or a Zoom71 using a vascular phantom in which a clot model was introduced. Rate of ingestion, complete recanalization after a single attempt, and pressure at the catheter tip for both devices were recorded. A retrospective analysis from a prospectively-maintained database was performed. Patient demographics, periprocedural metrics, discharge and 90-day modified Rankin Scales were collected. Patients were divided into two groups based on which aspiration catheter was used. Results: In our bench-top experiment, complete ingestion of the clot occurred in 90% of beveled tip and 20% of control device experiments (p=0.006). Our clinical data demonstrated no significant difference in age, gender, IV tPA administration, admission NIHSS, baseline mRS, or LVO location between the beveled tip and flat tip groups. With the beveled tip, TICI 2C or better recanalization was more frequent (93.2% vs 74.2%, p-value 0.017), stent retriever usage was lower (9.1% versus 29%, p-value 0.024), and patients had lower mRS on discharge (median 3 vs 4, p less than 0.001) and at 90 days (median 2 vs 4, p=0.008). Conclusion: The beveled tip design leads to more frequent clot ingestion in a bench top model, which may translate into a more efficacious thrombectomy device with improved outcomes.

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