Footfall energy harvesting : footfall energy harvesting conversion mechanisms

Ubiquitous computing and pervasive networks are prevailing to impact almost every part of our daily lives. Convergence of technologies has allowed electronic devices to become untethered. Cutting of the power-cord and communications link has provided many benefits, mobility and convenience being the most advantageous, however, an important but lagging technology in this vision is the power source. The trend in power density of batteries has not tracked the advancements in electronic systems development. This has provided opportunity for a bridging technology which uses a more integrated approach with the power source to emerge, where a device has an onboard self sustaining energy supply. This approach promises to close the gap between the increased miniaturisation of electronics systems and the physically constrained battery technology by tapping into the ambient energy available in the surrounding location of an application. Energy harvesting allows some of the costly maintenance and environmentally damaging issues of battery powered systems to be reduced.This work considers the characteristics and energy requirements of wireless sensor and actuator networks. It outlines a range of sources from which the energy can be extracted and then considers the conversion methods which could be employed in such schemes. This research looks at the methods and techniques for harvesting/scavenging energy from ambient sources, in particular from the motion of human traffic on raised flooring and stairwells for the purpose of powering wireless sensor and actuator networks. Mechanisms for the conversion of mechanical energy to electrical energy are evaluated for their benefits in footfall harvesting, from which, two conversion mechanisms are chosen for prototyping.The thesis presents two stair-mounted generator designs. Conversion that extends the intermittent pulses of energy in footfall is shown to be the beneficial. A flyback generator is designed which converts the linear motion of footfall to rotational torque is presented. Secondly, a cantilever design which converts the linear motion to vibration is shown. Both designs are mathematically modelled and the behaviour validated with experimental results & analysis. Power, energy and efficiency characteristics for both mechanisms are compared. Cost of manufacture and reliability are also discussed

Feedback Control Theory in Stochastic Dynamical Systems

A stochastic dynamical system is a system composed of many interacting components which includes stochastic behavior. Feedback control theory is designed to use information from the current state of the system in order to temper the final state toward the desired outcome. In this dissertation, I perform studies on two choices of classic and quantum dynamical systems to cover vast variety of statistical tools and methods. For classical model, I perform a study on finite-size effects at the phase transition in the Nagel-Schreckenberg traffic model as an example of non-equilibrium many body stochastic dynamical system. For quantum mechanical model, I introduce an optimal measurement-based feedback control protocol for cooling a single qubit as an example of complex system with one cell and many degrees of freedom. I examine the Nagel-Schreckenberg traffic model for a variety of maximum speeds. I show that the low density limit can be described as a dilute gas of vehicles with a repulsive core. At the transition to jamming, I observe finite-size effects in a variety of quantities describing the flow and the density correlations, but only if the maximum speed Vmax is larger than a certain value. A finite-size scaling analysis of several order parameters shows universal behavior, with scaling exponents that depend on Vmax The jamming transition at large Vmax can be viewed as the nucleation of jams in a background of freely flowing vehicles. Feedback control of quantum systems via continuous measurements involves complex nonlinear dynamics. As a result, even for a single qubit the optimal measurement for feedback control is known only in very special cases. I show here that for a broad class of noise processes, a series of compelling arguments can be applied to greatly simplify the problem of steady-state preparation of the ground-state, while loosing little in the way of optimality. Using numerical optimization to solve this simplified control problem, I obtain for the first time a non-trivial feedback protocol valid for all feedback strengths in the regime of good control. The protocol can be described relatively simply, and contains a discontinuity as a function of feedback strength

TelA Promoted Telomere Resolution Features an Underwound Pre-cleavage Intermediate

Agrobacterium tumefaciens and Borrelia species are two examples of prokaryotic organisms that have linear replicons, in contrast to most prokaryotes that have circular genomes. These organisms can replicate the lagging strand end of linear (deoxyribonucleic acid) DNAs without the loss of the DNA’s information due to the covalently closed DNA hairpin telomeres at the termini of the DNA. Replication of DNAs with hairpin telomeres produces a circular inverted repeat dimer with replicated telomere junctions. This intermediate cannot be segregated into two daughter cells without a two-step DNA breakage and rejoining process known as telomere resolution. Specialized enzymes known as telomere resolvases create hairpin telomeres from a dimeric replication intermediate through telomere resolution. Telomere resolvases share a similar mechanism to that of topoisomerase-IB and tyrosine recombinase enzymes. The proposed models for telomere resolution include a pre-cleavage intermediate where the base pairing between the scissile phosphates is broken helping to propel the reaction forwards. A class of variants was examined in previous studies on the borrelial telomere resolvase, ResT. These variants were inactive on parental substrates but were rescued by substrate alterations that mimicked DNA unwinding between the cleavage sites. In ResT, the catalytic domain and the hairpin-binding module cooperate to stabilize an underwound pre-cleavage intermediate. The idea that the telomere resolvase from Agrobacterium tumefaciens, TelA, and ResT follow the same reaction pathway was generated from the crystal-structure data of TelA, and the homology between ResT and TelA. We generated TelA variants homologous to those in ResT that stabilize the pre-cleavage intermediate. We also generated TelA variants of sidechains that were shown to interact with the hairpin turnarounds in TelA structures. Reaction analysis showed that the central two basepairs of the replicated telomere (rTel) junction are likely to be underwound and stabilized by TelA in a pre-cleavage intermediate. We also have evidence that the next two basepairs are also broken and likely have a base flipped out of the helix in the pre and post-cleavage intermediate. It is predicted that an underwound pre-cleavage intermediate drives the reaction forward and ensures reaction completion

Finite-size effects in the Nagel-Schreckenberg traffic model

We examine the Nagel-Schreckenberg traffic model for a variety of maximum speeds. We show that the low-density limit can be described as a dilute gas of vehicles with a repulsive core. At the transition to jamming, we observe finite-size effects in a variety of quantities describing the flow and the density correlations, but only if the maximum speed Vmax is larger than a certain value. A finite-size scaling analysis of several order parameters shows universal behavior, with scaling exponents that depend on Vmax. The jamming transition at large Vmax can be viewed as the nucleation of jams in a background of freely flowing vehicles. For small Vmax no such clean separation into jammed and free vehicles is possible

Prioritizing the Main Elements of Quality Costs in Design-Build Mass-Housing Projects

Reducing the cost of quality in mass-housing projects can reduce the overall cost and can also result in increasing profitability or the possibility of getting more projects due to the lower price offered in the tenders. The first step to reduce the cost of quality is to identify different elements, determine their impact on the final product quality and then prioritize them. In this study, questionnaires and structured interviews with experienced construction professionals were employed to identify and prioritize the fundamental elements using the P-A-F (prevention, evaluation, and failure) method, one of the most well-known methods for categorizing quality costs. The results indicate a high impact of preventive activities and the low impact of external failure activities on final product quality. According to the results, the use of experienced specialists and skilled workers is more effective than in-service training of inexperienced forces. Corrective actions of non-conformities and design improvements have a significant impact on final product quality. The new approach to COQ elements ranking, used in this research, can help decision-makers to prioritize the most effective activities in construction projects to increase final quality with an optimum quality cost

Effect of saffron oral capsule on anxiety and quality of sleep of diabetic patients in a tertiary healthcare facility in southeastern Iran: A quasi-experimental study

Purpose: To determine the effect of oral capsule of saffron (a herbal medicine) on anxiety and quality of sleep of diabetic patients of a tertiary healthcare facility in Zabol, Iran in 2016.Methods: This was a quasi-experimental study on 50 diabetics of Zabol who met the inclusion criteria. Participants were randomly split into two groups (control and test). Anxiety and quality of sleep were evaluated by Spielberger Anxiety Inventory and Pittsburgh Sleep Quality Index (PSQI). Participants in the intervention group received a daily (between 12 noon and 2 pm) intake of 300 mg saffron capsule after lunch while those in the control group received a placebo daily for a similar duration. After a week, anxiety and sleep quality were assessed.Results: A significant difference in anxiety and quality of sleep prior to and after saffron oral capsule intake (p = 0.001) was observed. In the control group, anxiety and quality of sleep did not show any significant difference before and after intervention (p = 0.001).Conclusion: The results show that saffron capsule intake is effective in reducing anxiety and improving the quality of sleep among diabetic patients. Further studies are required to enhance saffron capsule formulation.Keywords: Anxiety, Blood glucose, Sleep, Diabetes mellitu

Studying the impact of mental health on job performance of managers and staff

The purpose of present research is to study the relationship between job performance and employees’ mental health in one of Iranian natural gas refinery located in city of Jam, Iran. Data collection was conducted based on two major characteristics of job performance and mental health based on questionnaire methods among 42 people. The methodology is descriptive and correlation – type and to analyze the data, Pearson’s correlation coefficient, variances equality tests as well as t-student were utilized. The findings show that there was a significant relationship between employees’ job performance and mental health and any increase in mental health aspects promotes job performance proportionally. In the meantime, there was no significant relationship between employees’ job performance and their gender and there was no significant difference on mental health status between male and female staff. Based on the results, one can conclude that low mental health level among employees can reduce their performance. Managers should use proper methods to decrease the negative consequences resulted from the lack of mental health in workplaces

Detecting Railway Under-Track Voids using Multi-Train In-Service Vehicle Accelerometer

The Siemens track monitoring system is being developed in collaboration with Rail Safety and Standards Board (RSSB) and the Institute of Railway Research at the University of Huddersfield. It makes use of the existing on-board GSM-R cab radio present in every train in the UK, through the fitment of a sensor card, which detects track condition over three axes of train vibrations. By using advanced on-train signal processing, only a small amount of data to be transferred to the Ground System. For voided switches and crossings (S&C), the GPS location allows the S&C asset number to be identified and reported. This ensures maintenance staff are accurately directed to the location of voids, minimising time spent inspecting and maintaining track and improving safety. The Ground System monitors the voids detected by multiple trains, to increase the reported accuracy (within 5m) of voids and to reduce false alarms. Automated void reporting, including whether the voids are located at S&C or other track types (such as plain-line track or bridges), allows maintenance to be directed and planned. The Ground System provides advanced warning of track defects, allowing more effective and prioritised preventative maintenance. The real benefit of the track monitoring system is that, by way of a simple activation, it can be present on every train within the UK and therefore be monitoring the track on a large number of train journeys, providing a network-wide track monitoring system. Recent on-train trials have shown that the small low-cost sensor is able to detect voided sleepers underneath both S&C and bridges. The repeatability between trains and for different journeys was found to be excellent. The Network Rail upgrades to the Siemens cab radio, planned for the next 2-3 years include a GSM-R/GPS antenna, and the addition of a GPS module to the cab radio, providing a GPS connection in every train. As part of these upgrades Siemens will introduce a the sensor card into the cab radio, minimising installation costs, making it hardware ready for track monitoring, the Siemens implementation of RCM (Remote Condition Monitoring). The only action needed for activation will be the upload of the software application to the cab radio. The track monitoring system allows the network operator to make significant reductions in maintenance and delay costs, line closures, journey re-planning and speed restrictions, by having a reliable monitoring system that is non-intrusive yet gives analysis for the entire rail network, improving train safety, network reliability and passenger comfort