36 resultados para ENERGY SYSTEMS

em Deakin Research Online - Australia


Relevância:

100.00% 100.00%

Publicador:

Resumo:

A large number of team games require participants to repeatedly produce maximal or near maximal sprints of short duration with brief recovery periods. The purpose of the present study was to determine the relationship between a repeated sprint ability (RSA) test that is specific to the energy demands of Australian Rules football (ARF), and the aerobic and anaerobic energy systems


Seventeen ARF players participated in the study. Each participant was assessed for VO2 max, accumulated oxygen deficit (AOD), best 20 m sprint time and RSA. The RSA test involved 12x20 m sprints departing every 20 s. When including the work performed during the time taken to decelerate, the test involved a work to rest ratio of approximately 1:3. Total sprinting time and the percentage decrement of repeated sprinting times were the two derived measures of RSA.

The results indicate that the best 20 m sprint time was the only factor to correlate significantly with total sprinting time (r = 0.829, P<0.001) and percentage decrement (r = -0.722, P<0.01). VO2 max and AOD were not related to the total sprinting time or the percentage decrement that was produced by the RSA test. This was interpreted to signify that the phosphagen system was the major energy contributor for this test.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

The Borough of Queenscliffe has identified the importance of reducing its greenhouse gas emissions and aims to become a carbon zero municipality by 2020. For a house, suburb or town to become carbon neutral ideally it produces an equivalent amount of energy from renewable resources to that which it consumes. By increasing the number of solar systems, both photovoltaic (PV) and hot water, in the residential sector, greenhouse gas emissions will be reduced. The number of solar systems located in the Borough of Queenscliffe has been estimated and a database of these systems has been created, including the size and panel orientation. The energy generated by each solar system, in addition to the reductions in greenhouse gas emissions, has been calculated for an average year.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Although Renewable energy applications in Middle East countries were started in the middle of the seventies, they have only gained momentum in the last ten years. Considering the past gained experience, a proposed national Renewable Energy (RE) plan aims toward bringing RE into the main stream of the national energy supply system with a target contribution of 10% of the electricity demand by the year 2020. The proposed plan calls for a wide spectrum of renewable energy applications. This paper will highlight renewable energy applications in Middle East countries, the gained experience, the RE resources, and the future prospects for the utilization of RE recourses.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

The charging of an undivided cerium–zinc redox battery by various current waveforms some of which mimic the output of renewable energy (solar, wind, tidal, biofuel burning) to electricity transducers is considered in this work, where the battery operates through diffusion-only conditions, and is discharged galvanostatically. Under reasonable assumption, the mathematical model developed enables the observation that the performance characteristic of the cells charged with a constant power input differentiates between the various current–charge waveforms, with cell geometry and electrode kinetics playing subtle, but significant, roles; in particular, high efficiency is observed for sunlight-charged batteries which are thin and suffer no corrosion of the sacrificial electrode, and which have already experienced a charge–discharge cycle. The performance characteristics of the systems are interpreted in the light of consequences for smart grid realisation, and indicate that, for a constant power input, the most matched renewable is biofuel burning with a current output that linearly increases with time.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

© 2015 IEEE.This paper presents an H« controller synthesised based on linear matrix inequalities (LMI) for a current source converter based superconducting magnetic energy systems (SMESs) connected to a node of power systems where the regulation of grid current has considered as a control objective. To facilitate the control design, the system is represented in terms of state space realization with uncertainties. The control design involves selecting proper weighting functions and performing LMI-synthesis. The controller order is reduced by Henkel-norm method. Simulations are carried out to evaluate the characteristics of the controller under parametric uncertainties. It is found out that the proposed controller is inherently stable, possesses significantly small tracking error, and preserves robust performance for the SMES.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

This paper presents a distributed multi-agent scheme to detect and identify cyber threats on the protection systems of power grids. The integration of information and communication technologies (ICTs) into existing power grids builds critical cyberphysical energy systems CPESs) in which digital relays are networked cyber-physical components subject to various cyber threats. Cyber attacks on protection systems may mimic real faults, cause component failure, and disable the communication links. Agents utilize both cyber and physical properties to reinforce the detection technique and further distinguish cyber attacks from physical faults. This paper also introduces the problem of secure communicationprotocols and highlights the comparative studies for enhancing thesecurity of the protection systems. The proposed scheme is validatedusing a benchmark power system under various fault and cyber attack scenarios.

Relevância:

70.00% 70.00%

Publicador:

Resumo:

There are 3 distinct yet closely integrated processes that operate together to satisfy the energy requirements of muscle. The anaerobic energy system is divided into alactic and lactic components, referring to the processes  involved in the splitting of the stored phosphagens, ATP and  phosphocreatine (PCr), and the nonaerobic breakdown of carbohydrate to lactic acid through glycolysis. The aerobic energy system refers to the combustion of carbohydrates and fats in the presence of oxygen. The anaerobic pathways are capable of regenerating ATP at high rates yet are limited by the amount of energy that can be released in a single bout of intense exercise. In contrast, the aerobic system has an enormous capacity yet is somewhat hampered in its ability to delivery energy quickly. The focus of this review is on the interaction and relative contribution of the energy systems during single bouts of maximal exercise. A particular emphasis has been placed on the role of the aerobic energy system during high intensity exercise.

Attempts to depict the interaction and relative contribution of the energy systems during maximal exercise first appeared in the 1960s and 1970s. While insightful at the time, these representations were based on calculations of anaerobic energy release that now appear questionable. Given repeated reproduction over the years, these early attempts have lead to 2 common misconceptions in the exercise science and coaching professions. First, that the energy systems respond to the demands of intense exercise in an almost sequential manner, and secondly, that the aerobic system responds slowly to these energy demands, thereby playing little role in determining performance over short durations. More recent research suggests that energy is derived from each of the energy-producing pathways during almost all exercise activities. The duration of maximal exercise at which equal contributions are derived from the anaerobic and aerobic energy systems appears to occur between 1 to 2 minutes and most probably around 75 seconds, a time that is considerably earlier than has traditionally been suggested.

Relevância:

70.00% 70.00%

Publicador:

Resumo:

While researchers are trying to solve the world's energy woes, hydrogen is becoming the key component in sustainable energy systems. Hydrogen could be produced through photocatalytic water-splitting technology. It has also been found that hydrogen and methane could be produced through photocatalytic reduction of carbon dioxide with water. In this exploratory study, instead of coating catalysts on a substrate, pellet form of catalyst, which has better adsorption capacity, was used in the photo-reduction of carbon dioxide with water. In the experiment, some water was first absorbed into titanium dioxide pellets. Highly purified carbon dioxide gas was then discharged into a reactor containing these wet pellets, which were then illuminated continuously using UVC lamps. Gaseous samples accumulated in the reactor were extracted at different intervals to analyze the product yields. The results confirmed that methane and hydrogen were photosynthesized using pellet form of TiO2 catalysts. Hydrogen was formed at a rate as high as 0.16 micromoles per hour (μmol h−1). The maximum formation rate of CH4 was achieved at 0.25 μmol h−1 after 24 h of irradiation. CO was also detected.

Relevância:

70.00% 70.00%

Publicador:

Resumo:

The integration of solar energy systems into buildings has been the subject of considerable commercial and academic research, particularly building integrated photovoltaics. However, the integration of solar hot water systems into roofing systems has had far less attention. This paper presents the theoretical and experimental results of a novel building integrated solar hot water system developed using existing long run roofing materials.

This work shows that it is possible to achieve effective integration that maintains the aesthetics of the building and also provides useful thermal energy. The results of an unglazed 108m2 swimming pool heater and 8m2 glazed domestic hot water systems are presented.

The experimental results show that the glazed system performs close to the theoretical model and is an effective provider of hot water in certain climates. However it was also found that for larger scale building integrated solar water heating systems, special attention must be paid to the configuration and arrangement of the collectors in order to minimise problems with respect to flow distribution and its effect on collector and system efficiency.

Relevância:

70.00% 70.00%

Publicador:

Resumo:

Accurate Short Term Load Forecasting (STLF) is essential for a variety of decision making processes. However, forecasting accuracy may drop due to presence of uncertainty in the operation of energy systems or unexpected behavior of exogenous variables. This paper proposes the application of Interval Type-2 Fuzzy Logic Systems (IT2 FLSs) for the problem of STLF. IT2 FLSs, with extra degrees of freedom, are an excellent tool for handling prevailing uncertainties and improving the prediction accuracy. Experiments conducted with real datasets show that IT2 FLS models appropriately approximate future load demands with an acceptable accuracy. Furthermore, they demonstrate an encouraging degree of accuracy superior to feedforward neural networks used in this study.

Relevância:

70.00% 70.00%

Publicador:

Resumo:

Accurate short term load forecasting (STLF) is essential for a variety of decision-making processes. However, forecasting accuracy can drop due to the presence of uncertainty in the operation of energy systems or unexpected behavior of exogenous variables. This paper proposes the application of Interval Type-2 Fuzzy Logic Systems (IT2 FLSs) for the problem of STLF. IT2 FLSs, with additional degrees of freedom, are an excellent tool for handling uncertainties and improving the prediction accuracy. Experiments conducted with real datasets show that IT2 FLS models precisely approximate future load demands with an acceptable accuracy. Furthermore, they demonstrate an encouraging degree of accuracy superior to feedforward neural networks and traditional type-1 Takagi-Sugeno-Kang (TSK) FLSs.

Relevância:

70.00% 70.00%

Publicador:

Resumo:

Nowadays, there is growing interest towards the area of building integrated photovoltaic (BIPV) systems and PV microgrids (MGs) in the field of power generation and distribution systems. This is mainly due to the higher adaptability and compatibility of these systems with preplanned sustainable development strategies in the most urban areas. The quiet operating process and movement free characteristic of photovoltaic systems brought them to the roof tops of the buildings in urban and rural areas and made them the most demanded means of renewable energy systems. This study highlights the problems affecting the performance and efficiency of BIPV systems and presents miscellaneous solutions and recommendations to solve these problems.

Relevância:

70.00% 70.00%

Publicador:

Resumo:

BACKGROUND OR CONTEXT: Current work in remote laboratories focuses on student interaction in a setting that can be at times disconnected from real world systems. Laboratories have been developed that show models of a working system, focusing on a single aspect, but very few laboratories allow the user to see the outputs of a working system that interacts with the real world as would be expected outside of a laboratory setting. It was aimed with this paper to show a design of a novel approach to building a remote laboratory that would be able to interact with a fully functional renewable energy system, and to show the students the outputs of such a system in real time. It allows for the user to be presented with information in a new context.
PURPOSE OR GOAL: With this research it is hoped to achieve a remote laboratory that will be able to present students with the data from a renewable energy system live, as it is generated as well as all the logged date generated. It is aimed with this novel approach to building a remote laboratory to assist the students in learning about renewable energy systems while allowing the student to access real data, instead of simulated data. Links to increased motivation due to realism in data given as well as change in student perception on learning in remote laboratories mean that a system such as this could change the way students approach learning about renewable energy generation systems. This will require further research however.
APPROACH: This remote laboratory required gathering data from an already established system. The live results were not recorded, and a log file was generated daily, however this was not fast enough to give to students as it was generated, so a system that could maintain communication between all systems, while also polling for data itself was required. In addition to this, the system had to communicate to a server that would give students access to the live data. The server was set up in such a way that students were not required to install any programs on their computer, multiple students could access the data at any given time, and a wide range of devices, including mobile devices, could all access the remote laboratory.
DISCUSSION: Key outcomes include the design of the remote laboratory, including screenshots of data acquisition from the renewable energy system from different devices. The design is split into two sections, one covering the server side architecture while another covers the data acquisition architecture. A very brief discussion on students’ initial interaction is also undertaken.
RECOMMENDATIONS/IMPLICATIONS/CONCLUSION: Research has shown that the degree of realism in remote education can have an effect on students’ behaviors/motivation in a remote laboratory. By allowing students to knowingly access a real system that is currently being used to generate power from renewable energy sources, the methods and motivations that students use when approaching renewable energy systems may change.

Relevância:

60.00% 60.00%

Publicador:

Resumo:

Research in pursuit of an effective response to the demands for a sustainable architecture has lead towards the conception of a Renewable, Adaptive, Recyclable and Environmental (R.A.R.E.) building typology. The term R.A.R.E. expresses issues that have assumed central importance in the current architectural debate. This paper establishes the principles of the typology, drawing on the contents and pedagogical methods applied in a building technology academic course, at fourth year level. The R.A.R.E methodology is presented to and explored by students in the search for a definition of an innovative architecture, which is both progressive and sustainable. The unit is structured into eight subjects: Sustainable Site & Climate Analysis; Flexible & Adaptive Structural Systems; Renewable & Environmental Building Materials; Modular Building Systems; Innovative Building Envelope Systems; Renewable & Non-conventional Energy Systems; Innovative Heating, Ventilation & Air Conditioning Systems; Water Collection & Storage Systems. Through a holistic and integrated approach, the unit presents a comprehensive overview of these ‘Sustainable Building Categories’, so that the students can produce a guide towards the design requirements of a Renewable, Adaptive, Recyclable and Environmental (R.A.R.E.) Architecture.

Relevância:

60.00% 60.00%

Publicador:

Resumo:

R.A.R.E. stands for Renewable Adaptive Recyclable Environmental Architecture; the acronym expresses a demand that is becoming increasingly important today in the eyes of designers and clients. The paper draws on the contents and the pedagogical methods applied in a Building Technology Unit (SRT 450) – at forth year level – at the School of Architecture and Building, Deakin University, Australia. The unit is basically structured upon eight subjects derived as relevant to the research and development for a R.A.R.E. Architecture: Sustainable Site & Climate Analysis; Flexible & Adaptive Structural Systems; Renewable Adaptive & Environmental Building Materials; Modular Building Systems; Innovative Building Envelope Systems; Renewable or Non-conventional Energy Systems; Innovative Heating, Ventilation & Air Conditioning; Water Storage & Systems. The overall objective of the unit is to present a comprehensive overview of all these Sustainable Building Categories (SBCs) so that the students can produce a guide towards the design of a R.A.R.E. Architecture. The push towards a holistic and integrated approach will contribute to the definition of an innovative architecture, which is both progressive and sustainable.