valve position
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2021 ◽  
pp. 81-107
Author(s):  
Nicolas Collins

The !trumpet is software synthesis system controlled from, and playing back through, a trumpet.  It is not an electronically extended trumpet: the player produces no acoustic sounds by blowing through the mouthpiece. Instead, breath pressure and valve movement on the brass instrument are read by an embedded Arduino microcontroller  and sent to a laptop, where the data is mapped onto various parameters in synthesis software; the resulting electronic sound is returned to the trumpet, where it plays through a loudspeaker inside the bell, and is further processed acoustically by valve position (changes in the length of tubing filter the speaker output), movement of a plunger mute (wah-wah style filtering), and orientation of the instrument in space (panning).


2021 ◽  
Author(s):  
Elijah Kiplimo ◽  
Daniel Oyoo ◽  
Antonio Tapia ◽  
Marseline Jepng’etich

Abstract Wellheads have a major role in ensuring well integrity, providing access to the wellbore and flow control. It is vital to constantly monitor the wellhead fluid pressure and temperature effectively in order to maintain the full control of wellbore fluids. Over the years, wellheads have remained purely mechanical and have heavily relied on physical on-site monitoring. There is need to develop a reliable and accessible monitoring solutions for the wellheads in order to increase the effectiveness of the well integrity management systems and to get the full benefits of the wellhead data by incorporating the emerging data analytics technologies. This project details the development of a system that gathers wellhead temperature, pressure and the accurate valve position at any given time. The data gathering systems used in this project entail smart sensor technology capable of withstanding the wellbore pressures and temperatures. The system transmits the data securely, using blockchain, to an online platform where advanced data analytics using MATLAB and machine learning algorithms are used for visual data representation. The online platform additionally provides a means of real-time valve position control and takes into account the exact revolutions required for the opening and closure of the valve hence keeping a record for maintenance purposes. The innovative use and analysis of the data gathered form the wellhead provides insights for the operators and service companies and gives a way for setting ang thresholds in order to get alerts based in their custom specifications. This paper documents the development of a system that gathers wellhead data and provides a means of remote control of the wellhead valves. It covers the design phase, selection of appropriate sensor placement locations on the wellhead, the design of valve actuators, offline data gathering systems and the online data analysis and valve control platform. The project also pays a key attention towards the secure data transmission techniques and highlights the benefits of incorporating such a system in the oil and gas upstream sector.


Author(s):  
Pardeep Shahi ◽  
Apurv Deshmukh ◽  
Hardik Hurnekar ◽  
Satyam Saini ◽  
Pratik V Bansode ◽  
...  

Abstract Transistor density trends till recently have been following Moore's law, doubling every generation resulting in increased power density. The computational performance gains with the breakdown of Moore's law were achieved by using multi-core processors, leading to non-uniform power distribution and localized high temperatures making thermal management even more challenging. Cold plate-based liquid cooling has proven to be one of the most efficient technologies in overcoming these thermal management issues. Traditional liquid-cooled data center deployments provide a constant flow rate to servers irrespective of the workload, leading to excessive consumption of coolant pumping power. Therefore, a further enhancement in the efficiency of implementation of liquid cooling in data centers is possible. The present investigation proposes the implementation of dynamic cooling using an active flow control device to regulate the coolant flow rates at the server level. This device can aid in pumping power savings by controlling the flow rates based on server utilization. The FCD design contains a V-cut ball valve connected to a micro servo motor used for varying the device valve angle. The valve position was varied to change the flow rate through the valve by servo motor actuation based on pre-decided rotational angles. The device operation was characterized by quantifying the flow rates and pressure drop across the device by changing the valve position using both CFD and experiments. The proposed FCD was able to vary the flow rate between 0.09 lpm to 4 lpm at different valve positions.


2021 ◽  
pp. 1-3
Author(s):  
Daiji Takajo ◽  
Pooja Gupta ◽  
Sanjeev Aggarwal

Abstract We report a neonate with dilated cardiomyopathy and have echocardiographic findings consistent with “functional” tricuspid atresia. There was an echo-bright, plate-like tissue at the tricuspid valve position with no forward flow across it. This report underscores the role of right ventricle intracavitary haemodynamic influence on the tricuspid valve leaflet excursion and demonstrates a phenomenon of “pseudo or functional tricuspid atresia” mimicking tricuspid atresia in a patient with acute presentation of cardiomyopathy.


Author(s):  
Bouziane Fersaoui ◽  
Mahfoudh Cerdoun ◽  
Abdelghani May ◽  
Carlo Carcasci

The valves of an internal combustion engine play an essential role in the automobiles and their surroundings significantly affect their thermo-mechanical behavior. The work aims to assess numerically the effect of the real thermo-mechanical boundary conditions on the valves by considering the actual complex surrounding. For this purpose, we have subdivided the valve into seven adequate zones. We have evaluated the average values of the transient heat transfer coefficient, the adiabatic wall temperature and the mechanical load at each subdivision are during the opening and the closing periods. A transient Finite Element Model under ANSYS APDL software is developed and simulations are carried out until reaching the steady state. The temperature distribution and the thermal stresses at each valve position is obtained and then analyzed. The main findings show that the stress intensity distribution is developed in the zones labelled stem guide port and seat local of large temperature gradients, which causes high thermal stresses responsible of cracks or thermal fatigue damage. In addition, knowing the temperature map, the thermal gradient and stress under actual conditions will surely help manufacturers to better design exhaust valve, avoid early failure and enhance the durability of valves.


2021 ◽  
Author(s):  
Nur'ain Minggu ◽  
Latief Riyanto ◽  
Chang Siong Ting ◽  
Dahlila Kamat ◽  
Dylan Zhe Ho ◽  
...  

Abstract This study aims to validate and track valve positions for all the zones applying recorded Distributed temperature sensing (DTS) and Distributed acoustic sensing (DAS) data interpretation in order to propose the best combination of downhole inflow control valve (ICV) openings, This is required to optimize Well X-2 multizone commingled production. Fiber DTS and DAS monitoring were relied on as an innovation against downhole conditions that has compromised the three out of four downhole dual-gauges and valve position sensors. For zonal water control purpose, ICV cycling and positioning have been attempted in 2019. The valve position tracking derived from the compromised downhole dual gauges and valve position sensors does not tally with the surface flow indication overall. Consequently, the original measurement intention of the permanently installed distributed fiber-optic which served as back-up zonal-rate calculation profiling and as potential sub-layer flow-contribution indicators is brought in as contingency zonal valve-opening tracking and guides that proved valuable for subsequent production optimization. First part of study involves interpretation of Distributed Temperature Sensing (DTS) data. Downloaded DTS data is depth matched and validated against known operating conditions like time of each cycling stage and surface well test parameters (i.e. Liquid Rate, Watercut, Tubing Head Pressure (THP), Total Gas, Gas-Oil Ratio (GOR)), etc. To establish a baseline, several DTS traces of historical operating condition during a known stable period were selected, i.e. stable flowing condition at only Zone 4 stable shut-in condition at surface with only ICV Zone 4 is opened Downhole valve-position tracking can be interpreted alternatively from induced fiber temperature activities across the valve depth with a good temperature baseline benchmarking from DTS temperature profiling. Second part of study involves interpretation of Distributed Acoustic Sensing (DAS) data. The data was acquired under single flowing condition one month post-ICV cycling. Without any changes made on the well operating conditions, the well is flowing under same condition post ICV cycling. Inflow point detection using joint interpretation of DAS and DTS, where simultaneously DAS spectral content (depth-frequency) was analysed alongside DTS traces to further discriminate between inflow and other noise sources. Through i) acoustic amplitude analysis, ii) DTS inversion, iii) noise speed and flow speed computation, composite production allocation can be derived for Well X-2. Using the alternative co-interpretations based on fiber temperature and acoustic measurement, it is found and validated that Zone 1 ICV is Closed, Zone 2, 3 and 4 are in opened position and continuously producing at any cycles. This is in conflict of zonal production control understanding initially based on the compromised downhole sensors indicating that all the zonal valves are supposedly in fully closed position. In this case-study, DTS and DAS data has been proven useful and as an innovative, alternative monitoring to determine downhole valve opening with analogue to flow contribution derivation methodology. Therefore, anytime in the future where Well X-2 valves cycling is planned to be carried out, there is now a corresponding operating procedure that is incorporated onsite real-time fiber optic DTS and/or DAS data monitoring to validate tracked valves positioning.


2021 ◽  
Vol 24 (2) ◽  
pp. E209-E214
Author(s):  
Zeyi Cheng ◽  
Tingting Fang ◽  
Dandan Wang ◽  
Yingqiang Guo

Background: Tricuspid valve replacement (TVR) is seldom performed in cardiac valve surgery, and there currently are no clinical guidelines as to which type of prostheses is better in tricuspid valve position. This meta-analysis was performed to compare the results of mechanical and biological prostheses for TVR. Methods: We searched the Pubmed, Cochrane, and Embase clinical trial databases to collect all related studies published from January 1, 2000 to July 31, 2020. A random-effects model was used to evaluate the odds ratios (OR) and its 95% confidence intervals (CI) of time-to-event related effects of the surgical procedures; every study’s quality was evaluated by the Newcastle-Ottawa Scale (NOS). Results: A total of 13 retrospective studies, including 1453 patients were analyzed. There were no statistically differences between mechanical and biological prostheses with respect to prosthetic valve failure [OR = 0.84, 95% CI(0.54, 1.28), P = .41], bleeding [OR = 0.84, 95% CI(0.54,1.28), P = .41], reoperation [OR = 1.02, 95% CI(0.58,1.78), P = .95], early mortality [OR = 1.35, 95% CI(0.82,2.25), P = .24] and long-time survival [OR = 1.09, 95% CI(0.70, 1.69), P = .70], but a significant difference can be seen in mechanical prostheses with a higher risk of thrombosis [OR = 0.17, 95% CI(0.05, 0.60), P = .006, I2 = 0%]. Conclusions: In tricuspid valve position, mechanical valve prostheses have a higher risk of thrombosis than biological prostheses, but no statistical differences between mechanical and biological prostheses with respect to prosthetic valve failure, bleeding, reoperation, early mortality, and long-term survival. The valve disease and patient’s age and risk factors are the most important considerations in the decision-making process. The more specific conclusion needs to be further proved by large-sample, multi-center, randomized, double-blind and control trials.


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