scholarly journals HPQS: A Fast, High-Capacity, Hybrid Priority Queuing System for High-Speed Networking Devices

IEEE Access ◽  
2019 ◽  
Vol 7 ◽  
pp. 130672-130684
Author(s):  
Imad Benacer ◽  
Francois-Raymond Boyer ◽  
Yvon Savaria
Sensors ◽  
2021 ◽  
Vol 21 (11) ◽  
pp. 3871
Author(s):  
Jiri Pokorny ◽  
Khanh Ma ◽  
Salwa Saafi ◽  
Jakub Frolka ◽  
Jose Villa ◽  
...  

Automated systems have been seamlessly integrated into several industries as part of their industrial automation processes. Employing automated systems, such as autonomous vehicles, allows industries to increase productivity, benefit from a wide range of technologies and capabilities, and improve workplace safety. So far, most of the existing systems consider utilizing one type of autonomous vehicle. In this work, we propose a collaboration of different types of unmanned vehicles in maritime offshore scenarios. Providing high capacity, extended coverage, and better quality of services, autonomous collaborative systems can enable emerging maritime use cases, such as remote monitoring and navigation assistance. Motivated by these potential benefits, we propose the deployment of an Unmanned Surface Vehicle (USV) and an Unmanned Aerial Vehicle (UAV) in an autonomous collaborative communication system. Specifically, we design high-speed, directional communication links between a terrestrial control station and the two unmanned vehicles. Using measurement and simulation results, we evaluate the performance of the designed links in different communication scenarios and we show the benefits of employing multiple autonomous vehicles in the proposed communication system.


Author(s):  
Tadashi Kataoka ◽  
Tadahiko Kishikawa ◽  
Shigeru Sakata ◽  
Takahiro Nakagawa ◽  
Jun Ishiguro

This paper presents the implementation of failure detection and diagnosis, and predictive maintenance for a microturbine cogeneration system. It also introduces a remote monitoring system with capabilities for high-capacity high-speed data acquisition and storage, as well as data sharing via the Internet. Additionally, this paper provides failure diagnosis that uses high-speed transient data in order to determine the root cause of microturbine emergency shutdown or start failure, as well as failure prediction that uses long-range trend data in order to carry out the appropriate maintenance with some examples.


Author(s):  
Richard H. Lyon ◽  
Leonid M. Malinin

Abstract In modern, high capacity circular knitting machines, the small and fragile latch needles are often a performance-limiting machine element (Schuler, 1980). For these machines, the operating circumferential speed may exceed 1.5 m/sec. Due to the kinematics of the process, the cam driven needles are exposed to periodic excitation with frequency proportional to the speed. Increase in rotational speed gives rise to needle head fatigue breakages unless special design measures are undertaken. Frequencies up to 15 kHz have been observed and up to 60 kHz may be expected in the vibration spectrum. To understand what particular features of needle design may be responsible for their longevity, several techniques were developed to apply Finite Element Analysis software to estimating the fatigue life under a non-harmonic periodic loading. The known FEA packages handle dynamics of a system with such loading as a general non-stationary problem, whereas much more efficient solution can be constructed by combining the analytical solution for a one DOF system under recurring impulses (5-functions of amplitude A) at the moments 0, T, 2T, …, and the natural modes of the system (with the driving point fixed) provided by FEA. As applied to the system in question, from the broad frequency range of the excitation forces and displacements, only frequencies close to those providing maxima to the transfer functions from the driving point to the head of the needle were selected. These frequencies are referred to further on as the response frequencies. Then the time history simulating polyharmonic stresses in the dangerous area was generated and processed according to the chosen fatigue criteria (a corrected linear hypothesis of damage summation, see below). Thus for any given node of the needle a point on the S-N diagram was obtained. A wide spread desktop package, ALGOR, was selected as a Linear Stress Analysis solver. The described procedure is built on top of this package and allows design engineers to make judgements as to what design is more advantageous for needle longevity.


ACS Omega ◽  
2019 ◽  
Vol 4 (21) ◽  
pp. 19293-19306 ◽  
Author(s):  
Imran Ali ◽  
Irina Burakova ◽  
Evgeny Galunin ◽  
Alexandr Burakov ◽  
Elina Mkrtchyan ◽  
...  

2013 ◽  
Vol 50 (5) ◽  
pp. 550-556 ◽  
Author(s):  
J. Mendes ◽  
O. Buzzi

The high-capacity tensiometer developed by Ridley and Burland in 1993 is a milestone in experimental unsaturated soil mechanics. This device, which relies on development of tension in an enclosed water body, permits direct measurement of negative water potential. Many tensiometers have been built since 1993, all being based on the same principle although the design may differ slightly from the original. In particular, the common characteristic is a very small water reservoir that is believed to be the location of bubble nucleation, a phenomenon referred to as cavitation that impedes the sensor from functioning properly. Many have studied cavitation and different explanations or cavitation mechanisms have been proposed. However, all the considerations put forward were derived without being able to capture what happened inside the water reservoir at cavitation. This is now achieved with the new tensiometer specifically designed to “see” inside the water reservoir during suction measurement. For the first time, cavitation has been captured via high-speed photography and the mechanisms of cavitation can be explained using physical evidence. The first outcome is that it is possible for a high-capacity tensiometer to function to its full range with a large water reservoir. Then, the analysis of high-speed photographs reveals that the bubbles triggering cavitation are nucleated in the ceramic and make their way to the water reservoir. Cavitation occurs only when the air phase reaches the water reservoir.


2020 ◽  
Vol 36 (3) ◽  
pp. 245-256
Author(s):  
Carlos B. Armijo ◽  
Derek P. Whitelock ◽  
Paul A. Funk ◽  
Joe W. Thomas

HighlightsExperimental high-capacity seed-cotton reclaimers were evaluated for the growing high-speed roller-ginning industry.The experimental reclaimers minimized the amount of seed-cotton loss compared to the conventional reclaimer, but had more seed loss than a conventional reclaimer.The conventional reclaimer had the lowest combined seed and lint loss when processing Pima cotton.An experimental reclaimer based on a current cotton gin machine had seed and lint losses nearly $10 per cotton bale less than the conventional reclaimer when processing Upland cotton.Abstract. In a roller ginnery, a reclaimer machine removes partially-ginned or unginned seed cotton (carryover) from the mixture of carryover and ginned cottonseed that is expelled from the roller-gin stand during operation and returns the carryover to the gin stand for re-ginning. Conventional seed-cotton reclaimers are marginally adequate in their capacity to handle the increased carryover that high-speed roller ginning produces. Overloading a reclaimer often leads to choke-ups and downtime for the ginnery. The objective of this study was to develop and test high-capacity reclaimers. A modified 3-saw cylinder stick machine and a modified 2-saw cylinder gin-stand feeder were tested and compared to a conventional reclaimer. The saw-cylinders in the modified machines were operated at standard full speed, 1/2 of full speed, and 3/4 of full speed. Both Pima and Upland cotton were included in this study because there is a sizable amount of roller-ginned Upland cotton. Results showed that the experimental reclaimers reclaimed more carryover than the conventional reclaimer. An effective reclaimer will 1) reclaim carryover without also capturing residual seed that will likely be removed with cotton trash when returned to the gin stand feeder (seed loss) and 2) allow seed to pass through to the seed storage while minimizing the amount of residual carryover that escapes with the seed (carryover loss). The experimental reclaimers minimized the amount of residual carryover loss, but they had more residual seed loss than the conventional reclaimer. Increasing the saw-cylinder speeds of the experimental reclaimers decreased the residual seed loss but increased the residual carryover loss. Estimates of the value of the lost seed and of the lint on the lost carryover revealed that the conventional reclaimer had the lowest combined loss of $3.56 per bale when processing Pima cotton and the experimental 2-saw feeder with saw-cylinders operating at full speed had the lowest combined loss of $6.89 per bale when processing Upland cotton. The results suggest that losses of lint and seed may be further reduced by using a combination in series of different types of reclaimers to take advantage of each of their respective best features. Keywords: Cotton ginning, Roller ginning, Seed-cotton reclaimer.


Author(s):  
Claudio Somaschini ◽  
Tommaso Argentini ◽  
Daniele Rocchi ◽  
Paolo Schito ◽  
Gisella Tomasini

The resistance to motion of trains is an essential requisite especially while designing high-speed trains and high-capacity railway lines. The optimisation of friction effects and aerodynamic performance can be done during the design stage of a new train but the actual value of the running resistance can be inferred only by means of full-scale tests during the operation of a train. A CEN standard (EN 14067-4) describes the methodologies for the assessment of the running resistance of railway vehicles starting from full-scale test measurements. According to this standard, the speed-dependent terms of the resistance force have to be determined by means of coasting tests on railway lines, whose characteristics must be well known. Since this is not always possible and small errors on the gradient could lead to major uncertainties in the evaluation of the resistance force, a new method for the estimation of the running resistance coefficients, irrespective of the characteristics of the track is proposed in this paper. The reliability of the method is verified by comparing the results with those obtained from the procedure proposed in the CEN standard. The comparison shows that the new methodology is able to evaluate the resistance coefficients with an accuracy equivalent to that of the other methods but with fewer tests and with a more robust procedure relying on a lesser number of parameters.


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