Artificial Neural Network and Wavelet Features Extraction Applications in Nitrate and Sulphate Water Contamination Estimation

This work expounds the review of non-destructive evaluation using near-field sensors and its application in environmental monitoring. Star array configuration of planar electromagnetic sensor is explained in this work for nitrate and sulphate detection in water. The experimental results show that the star array planar electromagnetic sensor was able to detect nitrate and sulphate at different concentrations. Artificial Neural Networks (ANN) is used to classify different levels of nitrate and sulphate contaminations in water sources. The star array planar electromagnetic sensors were subjected to different water samples contaminated by nitrate and sulphate. Classification using Wavelet Transform (WT) was applied to extract the output signals features. These features were fed to ANN consequently, for the classification of different levels of nitrate and sulphate concentration in water. The model is capable of distinguishing the concentration level in the presence of other types of contamination with a root mean square error (RMSE) of 0.0132 or 98.68% accuracy

Development of Optical Biosensor Technologies for Cardiac Troponin Recognition

Acute myocardial infarction (AMI) is the leading cause of death among cardiovascular diseases. Among the numerous attempts to develop coronary marker concepts into clinical strategies, cardiac troponin is known as a specific marker for coronary events. The cardiac troponin concentration level in blood has been shown to rise rapidly for 4–10 days after onset of AMI, making it an attractive approach for a long diagnosis window for detection. The extremely low clinical sensing range of cardiac troponin levels consequently makes the methods of detection highly sensitive. In this review, by taking into consideration optical methods applied for cardiac troponin detection, we discuss the most commonly used methods of optical immunosensing and provide an overview of the various diagnostic cardiac troponin immunosensors that have been employed for determination of cardiac troponin over the last several years

Experimental validation of the solid state substation with embedded energy storage concept

This paper proposes the concept of integrating the energy storage within a Medium Voltage to Low Voltage solid state substation in order to provide new features compatible with the requirements from future more intelligent grids. The principles for the system development are presented and the role of each subsystem is explained. The experimental evaluation of the 1.9kVrms/25kVA substation with 1.5MJ of supercapacitor storage consists of subsystem tests showing the waveform quality, step transients as well as system tests of the efficiency, ride-through and power peak shaving operation

High-Performance Isolated Bidirectional DC-DC Converter

Conversores DC-DC bidireccionais têm vindo a ganhar atenção na área da eletrónica de potência devido ao aumento da necessidade de um fluxo de potência controlado entre dois barramentos DC. Aplicações típicas podem ser facilmente listadas, indo desde unidades de produção de energia renovável até veículos elétricos e híbridos. Estes conversores podem apresentar funcionalidades como elevada densidade energética e performance, assim como isolamento galvânico entre cada porto. Desta forma, a AddVolt requisitou que tal conversor fosse incluído na sua solução de travagem regenerativa. Com esta dissertação, um conversor DC-DC bidireccional e isolado é proposto, sendo que todos os aspetos desde revisão bibliográfica, modelação, design, simulação, implementação, teste e validação são abrangidos. Um conversor Dual-Active Bridge (DAB) de média potência e alta frequência é a topologia escolhida. Após validação de quer a topologia como a malha de controlo desenhada num ambiente computacional, um protótipo experimental é assemblado e testado com sucesso. O isolamento galvânico é garantido e atingido através de um transformador de alta frequência desenhado e enrolado pelo autor.Bidirectional DC-DC converters have been gaining attention in the field of power electronics due to the increasing need of a controlled power flow between two DC buses. Typical applications can be easily listed, ranging from renewable energy production units to electric and hybrid vehicles. Such converters can feature characteristics as high power density and performance as well as isolation between each port. As a result, AddVolt has commissioned that such a converter should be included in its regenerative breaking solution. Within this dissertation, a bidirectional isolated DC-DC converter is proposed, and all aspects from literature review, modelling, design, simulation, implementation, testing and validation are deeply covered. A medium-power high frequency Dual-Active Bridge (DAB) converter is the chosen topology. After validation of both the topology and control structure in a computational environment, an experimental prototype is assembled and successfully tested. Galvanic isolation is granted and achieved by a self-designed and in-house wound high frequency transformer

A Reuse Evaluation for Solar-Cell Silicon Wafers via Shift Revolution and Tool Rotation Using Magnetic Assistance in Ultrasonic Electrochemical Micromachining

A new reuse fabrication using a tool module with rotation and revolution through a process of magnetic assistance in ultrasonic electrochemical micromachining (UEMM) for removal of the surface layers from silicon wafers of solar cells is demonstrated. The target of the proposed reuse fabrication method is to replace the current approach, which uses strong acid and grinding and may damage the physical structure of silicon wafers and pollute to the environment. A precisely engineered clean production approach to removal of surface microstructure layers from silicon wafers is to develop a mass production system for recycling defective or discarded silicon wafers of solar cells that can reduce pollution and cost. The high revolution speed of the shift with the high rotation speed of the designed tool increases the discharge mobility and improves the removal effect associated with the high feed rate of the workpiece. High frequency and high power of ultrasonic with large electrolyte flow rate and high magnetic strengths with a small distance between the two magnets provide a large discharge effect and good removal; only a short period of time is required to remove the epoxy film and Si3N4 layer easily and cleanly

Study of an off-grid wireless sensors with Li-Ion battery and Giant Magnetostrisctive Material

L'abstract è presente nell'allegato / the abstract is in the attachmen