32 research outputs found
Anomaly Detection in聽Small-Scale Industrial and聽Household Appliances
Anomaly detection is concerned with identifying rare events/ observations that differ substantially from the majority of the data. It is considered an important task in the energy sector to enable the identification of non-standard device conditions. The use of anomaly detection techniques in small-scale residential and industrial settings can provide useful insights about device health, maintenance requirements, and downtime, which in turn can lead to lower operating costs. There are numerous approaches for detecting anomalies in a range of application scenarios such as prescriptive appliance maintenance. This work reports on anomaly detection using a data set of fridge power consumption that operates on a near zero energy building scenario. We implement a variety of machine and deep learning algorithms and evaluate performances using multiple metrics. In the light of the present state of the art, the contribution of this work is the development of a inference pipeline that incorporates numerous methodologies and algorithms capable of producing high accuracy results for detecting appliance failures
Fully Hydrogenated Beryllium Nanoclusters
We present the ground state and energetically
low structures of
Be<sub><i>n</i></sub>H<sub>2<i>n</i></sub> nanoclusters
as predicted using density functional theory (DFT) and employing the
M06 meta-hybrid exchange-correlation functional. Results using the
M06 functional are benchmarked against high accuracy coupled-cluster
CCSD颅(T) and found to be in excellent agreement. For small values of <i>n</i>, the linear or polymeric form is the lowest energy geometry,
while for sizes larger, <i>n</i> > 9 ring type and link
type structures are the energetically lowest configurations. This
trend has also been observed through ab initio molecular dynamics
(AIMD) simulations at finite temperatures. In addition to the binding
energies of the structures we report on polymerization energies, Be鈥揌
bond energies with respect to coordination details, hydrogen desorption
energies of saturated and oversaturated species, as well as computed
infrared spectra of all the ground state and energetically low lying
structures presented. Furthermore, we find that the saturated polymeric
forms of the nanoclusters <i>cannot</i> retain molecular
hydrogen, in contrast to what is expected when zero point energy corrections
are not taken into account