Stable Equilibrium of a Mechanical Energy Storage Device
Steven Odi-Owei,
Kenny Ayoka
Issue:
Volume 11, Issue 3, June 2023
Pages:
60-65
Received:
6 April 2023
Accepted:
25 June 2023
Published:
26 July 2023
Abstract: This study determines the energy of a fatigue-loaded shaft of circular cross-section, in stable equilibrium, deflecting during rotation even in the absence of external loads. The shaft is subjected to completely reversed stresses as well as torsion and bending stresses varying with rotation and introducing fatigue loading problems. The research was conducted in order to establish equilibrium condition at which a shaft subjected to fatigue loading can operate without axial vibration problems, divergence buckling, and instability at critical or above critical speeds. When inertia slows the shaft to rest, where the energy goes usually causes the shaft to rattle. At rest, kinetic energy is zero at that point while potential energy is maximum. The stability status of the shaft can eliminate rattling. The energy method is used, in this study, to develop force-displacement relations. It is also used to show that the total potential energy is minimum in the rotating shaft. Invoking the principle of minimum potential energy is a way to more easily derive the shaft energy related characteristics. The principle is used to analyze displacement and end points boundary conditions. Boundary conditions give prescription of displacements. The principle of virtual displacements and that of the minimum potential energy give the so-called stiffness (or displacement) method. The primary unknowns in that are the nodal displacements instead of the nodal forces. The strain-energy-density factor represents the strength of the elastic energy field in the vicinity of a crack-tip (with stress singularity) developed in the shaft. It was found that the energy which is a source of fluctuation in motion during shaft rotation was minimum when the total energy transferred to the shaft is minimum.
Abstract: This study determines the energy of a fatigue-loaded shaft of circular cross-section, in stable equilibrium, deflecting during rotation even in the absence of external loads. The shaft is subjected to completely reversed stresses as well as torsion and bending stresses varying with rotation and introducing fatigue loading problems. The research was...
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Research on Reliability of Online Monitoring Results of Factory Discharge Pollutant SO2 Based on Regression Analysis
Yang Shuo,
Pan Zhiqiang,
Niu Xingrong,
Geng Lei,
Sun Zhijing,
Ma Dongchang,
Wang Douwen
Issue:
Volume 11, Issue 3, June 2023
Pages:
66-73
Received:
18 June 2023
Accepted:
10 July 2023
Published:
4 August 2023
Abstract: Concerning the SO2 pollution source monitoring, discussed and even debated all the time, is in the environmental field. Adhere to purpose of "lucid waters and lush mountains are invaluable assets", the immediate task is to establish a complete and correct QA/QC monitoring system. In China, there are a large number of online devices, for its superiority compared with the laboratory technology, that undertake tests. However, it also has to be admitted that, the online system, belonging to a non-standard, shall paid more attention to its effectiveness. In this paper, a Deming regression technique of variable error model, with unbiased correction (CSS0), constant bias correction (CSS1) and linear bias correction (CSS2) step by step, is used to fit at levels between online and its standard system. F and t, as well as χ2 distribution test are subsequently followed by for the selected CSS. Finally, under the independent identical distribution (i.i.d) condition based on the bias correction, use A* test to predict series residuals, from the correction, for its i.i.d condition. The uncertainty assessment, brought by the correction under site precision, combines the various variation to the maximum extent, and avoid the complicated correlation, is helpful for the quality assurance of the online system.
Abstract: Concerning the SO2 pollution source monitoring, discussed and even debated all the time, is in the environmental field. Adhere to purpose of "lucid waters and lush mountains are invaluable assets", the immediate task is to establish a complete and correct QA/QC monitoring system. In China, there are a large number of online devices, for its superio...
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