Developing Prognostic Models Using Duality Principles for DC-to-DC Converters

Within the field of Integrated System Health Management, there is still a lack of technological approaches suitable for the creation of adequate prognostic model for large applications whereby a number of similar or even identical subsystems and components are used. Existing similarity among a number of different systems, which are comprised of similar components but with different topologies, can be employed to assign the prognostics of one system to other systems using an inference engine. In the process of developing prognostics, this approach will thereby save resources and time. This paper presents a radically novel approach for building prognostic models based on system similarity in cases where duality principle in electrical systems is utilized. In this regard, unified damage model is created based on standard Tee/Pi models, prognostics model based on transfer functions, and remaining useful life (RUL) estimator based on how energy relaxation time of system is changed due to degradation. An advantage is that the prognostic model can be generalized such that a new system could be developed on the basis and principles of the prognostic model of other systems. Simple electronic circuits, dc-to-dc converters, are to be used as an experiment to exemplify the potential success of the proposed technique validated with prognostics models from particle filter

Reliability enhanced EV using pattern recognition techniques

The following paper will contribute to the development of novel data transmission techniques from an IVHM perspective so that Electrical Vehicles (EV) will be able to communicate semantically by directly pointing out to the worst failure/threat scenarios. This is achieved by constructing an image-based data communication in which the data that is monitored by a vast number of different sensors are collected as images; and then, the meaningful failure/threat objects are transmitted among a number of EVs. The meanings of these objects that are clarified for each EV by a set of training patterns are semantically linked from one to other EVs through the similarities that the EVs share. This is a similar approach to wellknown image compression and retrieval techniques, but the difference is that the training patterns, codebook, and codewords within the different EVs are not the same. Hence, the initial image that is compressed at the transmitter side does not exactly match the image retrieved at the receiver's side; as it concerns both EVs semantically that mainly addresses the worst risky scenarios. As an advantage, connected EVs would require less number of communication channels to talk together while also reducing data bandwidth as it only sends the similarity rates and tags of patterns instead of sending the whole initial image that is constructed from various sensors, including cameras. As a case study, this concept is applied to DC-DC converters which refer to a system that presents one of the major problems for EVs

The appearance of a compact jet in the soft-intermediate state of 4U 1543-47

Recent advancements in the understanding of jet-disc coupling in black hole candidate X-ray binaries (BHXBs) have provided close links between radio jet emission and X-ray spectral and variability behaviour. In 'soft' X-ray states the jets are suppressed, but the current picture lacks an understanding of the X-ray features associated with the quenching or recovering of these jets. Here we show that a brief, ~4 day infrared (IR) brightening during a predominantly soft X-ray state of the BHXB 4U 1543-47 is contemporaneous with a strong X-ray Type B quasi-periodic oscillation (QPO), a slight spectral hardening and an increase in the rms variability, indicating an excursion to the soft-intermediate state (SIMS). This IR 'flare' has a spectral index consistent with optically thin synchrotron emission and most likely originates from the steady, compact jet. This core jet emitting in the IR is usually only associated with the hard state, and its appearance during the SIMS places the 'jet line' between the SIMS and the soft state in the hardness-intensity diagram for this source. IR emission is produced in a small region of the jets close to where they are launched (~ 0.1 light-seconds), and the timescale of the IR flare in 4U 1543-47 is far too long to be caused by a single, discrete ejection. We also present a summary of the evolution of the jet and X-ray spectral/variability properties throughout the whole outburst, constraining the jet contribution to the X-ray flux during the decay.Comment: Accepted to MNRAS. 11 pages, 6 figure

Estimation of growth parameters and mortality rate of common carp (Cyprinus carpio, Linnaeus 1758) population in the southern Caspian Sea

Common carp (Cyprinus carpio) represents one of the most economically important fish species in the Caspian Sea. In this study, growth and mortality parameters among population of common carp was investigated. Sampling was carried out weekly, using beach seine in the south of the Caspian Sea from October 2006 to September 2007. As a contribution to elaborating management programs for common carp, the age and growth of this species was calculated via scale, growth parameters and mortality rate by length frequency data obtained from commercial fishing and research beach seines. Ten age groups were recorded from 1+ to 10+ years old, being dominated by 4 and 5 year-old fish. The growth parameters based on scale reading data by length at age analysis were FL∞= 71.52cm and K = 0.16 per year for total population, FL∞= 70.54cm and K = 0.15 per year for males, and FL∞= 72.00 cm and K = 0.16 per year for females, whereas by length frequency analysis, these values were estimated as FL∞ equals 72.0, 69.3 and 73.0cm and K equals 0.18, 0.15 and 0.18 per year for total population, males and females, respectively. The total, natural and fishing mortality rates were 0.71, 0.29 and 0.42 per year, respectively