A Method for the Production of Longitudinal Sound Vibrations in a Rod

In connection with some work being done in the testing of acoustic wave filters in solid media, a method has been developed for the production of longitudinal sound vibrations in a rod. Electrical oscillations are generated in a vacuum tube oscillator, pass through two stages of power amplification, and are used as the input to a special oscillator attached to the end of the rod. This oscillator is similar in principle and construction to the Fessenden oscillator used in submarine sound signaling. Vibrations which have a fair purity of tone, and which have a considerable intensity over a wide range of frequencies are obtained in the rod

Stochastic Hosting Capacity in LV Distribution Networks

Hosting capacity is defined as the level of penetration that a particular technology can connect to a distribution network without causing power quality problems. In this work, we study the impact of solar photovoltaics (PV) on voltage rise. In most cases, the locations and sizes of the PV are not known in advance, so hosting capacity must be considered as a random variable. Most hosting capacity methods study the problem considering a large number of scenarios, many of which provide little additional information. We overcome this problem by studying only cases where voltage constraints are active, with results illustrating a reduction in the number of scenarios required by an order of magnitude. A linear power flow model is utilised for this task, showing excellent performance. The hosting capacity is finally studied as a function of the number of generators connected, demonstrating that assumptions about the penetration level will have a large impact on the conclusions drawn for a given network

Variation of the Intensity of the Spectral Lines of Mercury with the Velocity of the Exciting Electrons

A study has been made of the variation of the intensity of the spectral lines of mercury when excited by impact of electrons of controlled velocity. In accordance with some earlier observations by Dr. J. A. Eldridge, it is found that the lines divide into two classes. In one class the intensity of the line increases uniformly from zero to a certain limit as the velocity of the electrons increases above the minimum exciting velocity. In the other class the intensity rises rapidly to a maximum at a velocity not far above the minimum exciting velocity, and then decreases to a certain limit

A Demonstration of Dielectric Hysteresis in Rubber

During research in connection with the development of an electrostatic loudspeaker, an effect was discovered which led to some measurements on the attractive force between plates in a flat condenser. With the dielectric between the plates consisting of a layer of rubber dam in combination with a layer of air, the curves of attractive force vs. potential difference show a striking similarity to magnetic hysteresis curves

Residual Feed Intake as a Selection Tool

This publication explains how residual feed intake can be used as a helpful tool when deciding which sires and dams to utilize to obtain superior genetics

Mitigating the Impact of Personal Vehicle Electrification: a Power Generation Perspective

The number of electric vehicles on the road in the UK is expected to rise quickly in the coming years, and this is likely to have an impact on the operation of the power grid. This paper first quantifies the consequences of allowing a completely electric fleet to charge freely, then considers whether there is a practical way in which the impacts can be mitigated. We predict that, with an entirely electric fleet, the UK power generation capacity would need to increase by 1/3. We show that it is possible to completely mitigate this with controlled charging, although substantial infrastructure would be required. However, we propose a simple scheme which could largely avoid the negative effect and does not require the creation of new infrastructure. We show that this reduces the projected increase in peak electricity demand by 80-99%

Clustering of Usage Profiles for Electric Vehicle Behaviour Analysis

Accurately predicting the behaviour of electric vehicles is going to be imperative for network operators. In order for vehicles to participate in either smart charging schemes or providing grid services, their availability and charge requirements must be forecasted. Their relative novelty means that data concerning electric vehicles is scarce and biased, however we have been collecting data on conventional vehicles for many years. This paper uses cluster analysis of travel survey data from the UK to identify typical conventional vehicle usage profiles. To this end, we determine the feature vector, introduce an appropriate distance metric, and choose a number of clusters. Five clusters are identified, and their suitability for electrification is discussed. A smaller data set of electric vehicles is then used to compare the current electric fleet behaviour with the conventional one