This Thesys reports the study of a HGMS (High GradientMagnetic Separation) process for the treatment of industrialwastewaters that considers an assisted chemical-physical pre-treatment for the removal of heavy metals through the bound by adsorption with added iron-oxide particulate matter (hematite). The considered filter, constituted by ferromagnetic stainless steel wool and permanent magnets, is studied with a new approach based on a statistical analysis that requires the study of the trajectories of the particles. Experimental activity on a laboratory device has been carried out in order to test the model.

This doctorate thesis focuses on the application of micromachining fabrication technologies for the realization of Radio Frequency (RF) bandpass filters. The work has been inspired and supported by the European Space Agency (ESA) Contract No. 22706/09/NL/GLC of the ARTES 5 Workplan 2008 “Micro-machined Filters in Multi-layer Technology for Satellite On-board Communication Systems†(MIGNON Project). The main purpose of the project is the design and realization of high performance bandpass filters in the Ka and L/S band for on board applications. The use of modern micromachining technologies should allow for space and weight reduction as well as for a cost effective realization of these devices. In addition the tight tolerances obtained with micromachining techniques facilitate an industrial fabrication of filters with high yield. The thesis proposes novel concepts to accomplish this task and provides also the fabrication processes suitable to realize the devices. In addition this work gives also a deeper insight into critical fabrication steps like wafer to wafer thermocompression bonding using gold (Au) and silver (Ag) as an intermediate layer and fabrication of Through Silicon Vias (TSV).

Renewable Energy is considered as an effective solution for relieving the energy crisis and reducing the greenhouse gas emissions. It is also be recognized as an important energy resource for power supplying in the next generation power grid{smart grid system. For a long time, the unsustainable and unstable of renewable energy generation is the main challenge to the combination of the renewable energy and the smart grid. The short board on the utilities' remote control caused low-efficiency of power scheduling in the distribution power area, also increased the difficulty of the local generated renewable energy grid-connected process. Furthermore, with the rapid growth of the number of electrical vehicles and the widely established of the fast power charging stations in urban and rural area, the unpredictable power charging demand will become another challenge to the power grid in a few years. In this thesis we propose the corresponding solutions for the challenges enumerated in the above. Based on the architecture of terminal power consumer's residence, we introduce the local renewable energy system into the residential environment. The local renewable energy system can typically support part of the consumer's power demand, even more. In this case, we establish the architecture of the local smart grid community based on the structure of distribution network of the smart grid, includes terminal power consumer, secondary power substation, communication links and sub data management center. Communication links are employed as the data transmission channels in our scheme. Also the local power scheduling algorithm and the optimal path selection algorithm are created for power scheduling requirements and stable expansion of the power supply area. Acknowledging the fact that the information flow of the smart grid needs appropriate communication technologies to be the communication standards, we explore the available communication technologies and the communication requirements and performance metrics in the smart grid networks. Also, the power saving mechanism of smart devices in the advanced metering infrastructure is proposed based on the two-state-switch scheduling algorithm and improved 802.11ah-based data transmission model. Renewable energy system can be employed in residential environment, but also can be deployed in public environment, like fast power charging station and public parking campus. Due to the current capacity of electrical vehicles (EV), the fast power charging station is required not just by the EV drivers, but also demanded by the related enterprises. We propose a upgraded fast power charging station with local deployed renewable energy system in public parking campus. Based on the queueing model, we explore and deliver a stochastic control model for the fast power charging station. A new status called "Service Jumped" is created to express the service state of the fast power charging station with and without the support from the local renewable energy in real-time.

A Wireless Sensor Network (WSN) is a distributed collection of resource constrained tiny nodes capable of operating with minimal user attendance. Due to their flexibility and low cost, WSNs have recently become widely applied in traffic regulation, fire alarm in buildings, wild fire monitoring, agriculture, health monitoring, building energy management, and ecological monitoring. However, deployment of the WSNs in difficult-to-access areas makes it difficult to replace the batteries - the main power supply of a sensor node. It means that the power limitation of the sensor nodes appreciably constraints their functionality and potential applications. The use of harvesting components such as solar cells alone and energy storage elements such as super capacitors and rechargeable batteries is insufficient for the long-term sensor node operation. With this thesis we are going to show that long-term operation could be achieved by adopting a combination of hardware and software techniques along with energy efficient WSN design. To demonstrate the hardware power management, an energy scavenging module was designed, implemented and tested. This module is able to handle both alternating current (AC) based and direct current (DC) based ambient sources. The harvested energy is stored in two energy buffers of different kind, and is delivered to the sensor node in accordance with an efficient energy supply switching algorithm. The software part of the thesis presents an analytical criterion to establish the value of the synchronization period minimizing the average power dissipated by a WSN node. Since the radio chip is usually the most power hungry component on a board, this approach can help one to decrease the amount of power consumption and prolong the lifetime of the entire WSN. The following part of the thesis demonstrates a methodology for power consumption evaluation of WSN. The methodology supports the Platform Based Design (PBD) paradigm, providing power analysis for various sensor platforms by defining separate abstraction layers for application, services, hardware and power supply modules. Finally, we present three applications where we use the designed hardware module and apply various power management strategies. In the first application we apply the WSN paradigm to the entertainment area, and in particular to the domain of Paintball. The second one refers to a wireless sensor platform for monitoring of dangerous gases and early fire detection. The platform operation is based on the pyrolysis product detection which makes it possible to prevent fire before inflammation. The third application is connected with medical research. This work describes the powering of wireless brain-machine interfaces.

The Terahertz (THz) band of the electromagnetic spectrum, also defined as sub-millimeter waves, covers the frequency range from 300 GHz to 10 THz. There are several unique characteristics of the radiation in this frequency range such as the non-ionizing nature, since the associated power is low and therefore it is considered as safe technology in many applications. THz waves have the capability of penetrating through several materials such as plastics, paper, and wood. Moreover, it provides a higher resolution compared to conventional mmWave technologies thanks to its shorter wavelengths. The most promising applications of the THz technology are medical imaging, security/surveillance imaging, quality control, non-destructive materials testing and spectroscopy. The potential advantages in these fields provide the motivation to develop room-temperature THz detectors. In terms of low cost, high volume, and high integration capabilities, standard CMOS technology has been considered as an excellent platform to achieve fully integrated THz imaging systems. In this Ph.D. thesis, we report on the design and development of field effect transistor (FET) THz direct detectors operating at low THz frequency (e.g. 300 GHz), as well as at higher THz frequencies (e.g. 800 GHz – 1 THz). In addition, we investigated the implementation issues that limit the power coupling efficiency with the integrated antenna, as well as the antenna-detector impedance-matching condition. The implemented antenna-coupled FET detector structures aim to improve the detection behavior in terms of responsivity and noise equivalent power (NEP) for CMOS based imaging applications. Since the detected THz signals by using this approach are extremely weak with limited bandwidth, the next section of this work presents a pixel-level readout chain containing a cascade of a pre-amplification and noise reduction stage based on a parametric chopper amplifier and a direct analog-to-digital conversion by means of an incremental Sigma-Delta converter. The readout circuit aims to perform a lock-in operation with modulated sources. The in-pixel readout chain provides simultaneous signal integration and noise filtering for the multi-pixel FET detector arrays and hence achieving similar sensitivity by the external lock-in amplifier. Next, based on the experimental THz characterization and measurement results of a single pixel (antenna-coupled FET detector + readout circuit), the design and implementation of a multispectral imager containing 10 x 10 THz focal plane array (FPA) as well as 50 x 50 (3T-APS) visible pixels is presented. Moreover, the readout circuit for the visible pixel is realized as a column-level correlated double sampler. All of the designed chips have been implemented and fabricated in 0.15-µm standard CMOS technology. The physical implementation, fabrication and electrical testing preparation are discussed.

Modern communication and space systems such as satellite communication devices, radars, SAR and radio astronomy interferometers are realized with large antenna arrays since this kind of radiating systems are able to generate radiation patterns with high directivity and resolution. In such a framework conventional arrays with uniform inter-element spacing could be not satisfactory in terms of costs and dimensions. An interesting alternative is to reduce the array elements obtaining the so called "thinned arrays". Large isophoric thinned arrays have been exploited because of their advantages in terms of weight, consumption, hardware complexity, and costs over their filled counterparts. Unfortunately, thinning large arrays reduces the control of the peak sidelobe level (PSL) and does not give automatically optimal spatial frequency coverage for correlators. First of all the state of the art methodologies used to overcome such limitations, e.g., random and algorithmic approaches, dynamic programming and stochastic optimization algorithms such as genetic algorithms, simulated annealing or particle swarm optimizers, are analyzed and described in the introduction. Successively, innovative guidelines for the synthesis of large radiating systems are proposed, and discussed in order to point out advantages and limitations. In particular, the following specific issues are addressed in this work: 1. A new class of analytical rectangular thinned arrays with low peak sidelobe level (PSL). The proposed synthesis technique exploits binary sequences derived from McFarland difference sets to design thinned layouts on a lattice of P(P+2) positions for any prime P. The pattern features of the arising massively-thinned arrangements characterized by only P(P+1) active elements are discussed and the results of an extensive numerical analysis are presented to assess advantages and limitations of the McFarland-based arrays. 2. A set of techniques is presented that is based on the exploitation of low correlation Almost Difference Sets (ADSs) sequences to design correlator arrays for radioastronomy applications. In particular three approaches are discussed with different objectives and performances. ADS-based analytical designs, GA-optimized arrangements, and PSO optimized arrays are presented and applied to the synthesis of open-ended "Y" and "Cross" array configurations to maximize the coverage u-v or to minimize the peak sidelobe level (PSL). Representative numerical results are illustrated to point out the features and performances of the proposed approaches, and to assess their effectiveness in comparison with state-of-the-art design methodologies, as well. The presented analysis indicates that the proposed approaches overcome existing PSO-based correlator arrays in terms of PSL control (e.g., >1.0dB reduction) and tracking u-v coverage (e.g., up to 2\% enhancement), also improving the speed of convergence of the synthesis process. 3. A genetic algorithm (GA)-enhanced almost difference set (ADS)-based methodology to design thinned planar arrays with low-peak sidelobe levels (PSLs). The method allows to overcome the limitations of the standard ADS approach in terms of flexibility and performance. The numerical validation, carried out in the far-field and for narrow-band signals, points out that with affordable computational efforts it is possible to design planar array arrangements that outperform standard ADS-based designs as well as standard GA design approaches.