Oscillators are kernel components of electrical and electronic circuits. Discussion of history, mechanisms and design based on Barkhausens observation. Discussion of a Wien Bridge oscillator based on the question: Why does this circuit oscillate ?

The use of time-frequency entropy to quantitatively assess the stability of submerged arc welding process considering the distribution features of arc energy is reported in this paper. Time-frequency entropy is employed to calculate and analyze the stationary current signals, non-stationary current and voltage signals in the submerged arc welding process. It is obtained that time-frequency entr...

A dissected-leaved form of Ranunculus repens L. occurs in the temporary limestone lakes (turloughs) across the west of Ireland. Turloughs fill with groundwater for up to 8 months of the year. Under experimental conditions, these turlough populations demonstrated a higher rate of aerial and submerged photosynthesis than populations of the more typical broad-leaved ruderal form. The turlough popu...

Submerged marine investigation still remains a puzzle. The motivation behind this paper is to address the issues in plan and improvement of submerged vehicles with hindrance shirking and moving help for administrator in marine condition utilizing fluffy rationale controller. A symmetrical, practical and little measured submerged Remotely Operated Vehicle (ROV) with three thrusters is intended f...

The conventional placement protocol for submerged and non-submerged implants was proposed in the 1960s and 1970s. Multicenter studies have reported satisfactory success rates for both protocols and a similar loss of crestal peri-implant bone after implant loading (0.5 to 1.5 mm). In recent years, placement of submerged implants using a single surgical procedure was introduced, with the immediat...

The goals of this study are to develop models of radiative transfer for optically shallow waters with benthic substrates colonized by submerged aquatic vegetation (SAV). The models will enable prediction of upward spectral radiation from the seafloor, thereby permitting (i) the use of optical remote sensing to retrieve bathymetry, (ii) the search for submerged objects of anthropogenic origin an...

Estimating maximum scour depth is normally required in order to determine the depth of  bridge piles. The present paper uses the SSIIM Software which considers flow and sediment equations in a three dimensional manner. The software models flow field around circular bridge pile by resolving Navier-Stokes three-dimensional equations and k-  method, and by temporary solution of flow field and cont...

The discussion of hydrodynamic forces becomes an important issue in determining the dynamic behaviour Submerged Floating Tunnel Bridge (SFTB) structure. As stated Morison Equation, are affected by kinematics water particles, but up to this date, there only a few discussions for curved tube applications. This paper discusses effect curvature radius and depth level on get correction factor straig...