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Acquisition of Software as a Service is becoming increasingly common, even without the perception of the end user. In this model, the product ceased to be the main actor, and the service started to assume this role, with the internet being its means of access. In this scenario, SaaS-Qual is used as a way to establish instruments to mediate service quality. In this work, we present a model for measuring SaaS continuity intention by assessing the quality of service used by the user. Structural equations were used, and the proposed model is a refinement of the SaaS continuity intention model proposed by Benlian and information system quality assessed by DeLone & McLean's user satisfaction. The model was able to explain that the quality variables make up 45.4% of User Satisfaction, which added to the Perceived Utility explains 37.9% SaaS Intention of Continuity.

Pre-treatment proton radiography and computed tomography can improve precision of proton therapy. A compact imaging setup for small-animal proton radiography, based on a miniaturized Timepix detector is presented along with results from proof-of-concept experiments. The MiniPIX detector was placed behind a µ-CT calibration phantom with 10 different tissue-equivalent inserts. The intensity of the 70MeV proton beam was adjusted such that pixel signal clusters from individual protons on the detector could be resolved. Analysis and event filtering on various cluster properties were used to suppress unwanted events. The energy deposition of the selected clusters was converted to water-equivalent thickness (WET) of the traversed material using a conversion curve based on Monte Carlo simulations and measured clusters of protons after traversing PMMA slabs of known thickness. Despite a systematic underestimation of up to 3%, retrieved WET values are in good agreement with ground truth values from literature. The achieved spatial resolution ranges from 0.3 to 0.7 mm for phantom-detector-distances of 1 to 5 cm. Applicability to living animals is currently limited by the relatively long acquisition time of up to 20 minutes per radiography. This obstacle can however be overcome with the latest detector generation Timepix3, allowing to handle higher particle rates and thus requiring shorter irradiation times.

This article reports on a W-Band (75–110 GHz) Schottky diode based balanced envelope detector in microstrip technology, featuring a transition from WR-10 to microstrip. The manufactured detector provides 20 GHz of input RF bandwidth within the W-band. A video bandwidth between 4 GHz and 6 GHz is achieved for input RF frequencies between 75 GHz and 88 GHz, allowing error free transmission of signals up to 12 Gbit/s.

We present an outright W-Band (75–110 GHz) receiver, composed by a Schottky diode based balanced Envelope Detector (ED), built in microstrip technology in a hollow waveguide to microstrip transition which provides a WR-10 input interface. According to simulations the ED is able to demodulate amplitude shift keying (ASK) signals with data rates up to 15 Gbps at every carrier frequency within the whole W-Band. This ED presents an outstanding broadband operational bandwidth together with a compact design compared to other balanced EDs.

This paper describes a high-resolution 11.7b Time-to-Digital Converter (TDC) designed in a pure digital CMOS 130nm technology. The target architecture comprises a looped delay-line based on an inverter-based pulse-shrinking technique. The proposed technique can achieve a 0.82ps resolution with a dynamic range of 2.918ns, an integral nonlinearity (INL) of −2.4 to 2.11 and a differential nonlinearity (DNL) of −0.91 to 0.87 LSB. In addition, it occupies a low area of 0.148 mm2.

The integration of software systems running in different healthcare organizations is increasingly required in order exchange data and carrying out healthcare processes in coordinated ways. This integration is usually supported by integration platforms which are based on advanced middleware technologies, like the Enterprise Service Bus (ESB). In addition, data quality in the healthcare area is critical to take timely and accurate decisions for the health and well-being of patients. This paper proposes a data quality aware ESB (DQ-ESB) for e-Health integration platforms which allows assessing and enforcing data quality within inter-organizational data exchanges. DQ-ESB handles an extensible data quality model which includes quality characteristics identified within the Uruguayan e-Health context. DQ-ESB provides data quality solutions based on native ESB mechanisms (e.g. data transformation) and it was implemented leveraging the Switchyard ESB product.

This work reports on the design and simulation results of a reversible hollow waveguide to microstrip transition operating in the W-band. Simulations show satisfactory results in terms of S parameter, obtaining transmission coefficients (S 12 , S 21 ) above −0.4 dB and reflection coefficients (S 11 , S 22 ) below −17 dB in the full W-band.

This paper reports on an ultra-wideband (UWB) Schottky diode based balanced envelope detector for the L-, S-, C- and X- bands. The proposed circuit consists of a balun that splits the input signal into two 180° out of phase signals, a balanced detector, that demodulates the two signals, a low pass filter that rejects the second harmonic spurious from the Schottky diode and a bias tee that selects the optimum rectification point. The manufactured prototype is able to demodulate error free a 4 Gbps amplitude shift keying (ASK) signal at 4 GHz carrier frequency, leading to a record bitrate to frequency carrier ratio (Δb) of 100%. Besides this, the detector achieves error free demodulation for carrier frequencies between 4 and 8 GHz, while keeping the bitrate at 4 Gbps.

This paper describes the specification, modelling and design of an ontology-based news authoring environment for the Semantic Web, that takes into account the construction and use of an ontology of the Zika disease. CMSs are being adapted in order to receive semantic features, such as automatic generations of keywords, semantic annotation and tagging, content reviewing etc. We present here the infrastructure designed to foster research on semantic CMSs as well as semantic web technologies that can be integrated into an ontology-based news authoring environment.

In this paper an ultra-wideband (UWB) Schottky diode based envelope detector is reported. The detector consists of an input matching network, a Schottky diode and wideband output filtering network. The output network is tailored to demodulate ultra-wideband amplitude shift keying (ASK) signals up to 2.5 Gbps at 6–9 GHz carrier frequency. The detector uses microstrip and surface-mount device (SMD) components and it is fabricated on a Rogers 6002 substrate. Experimental results show error free transmissions up to 2.5 Gbps at an input power level of −11 dBm. The highest measured conversion gain of the detector is around −12 dB.

As multimedia traffic provides the dominating data flows on Internet channels nowadays, on-demand video streaming has also grown in popularity. Users watching on-demand streams are interested in receiving their video streams without interruption and at low cost. To achieve this, video providers need to build computational infrastructure that can adapt to changes in demand. This paper presents an architecture to build synergy between Peer-to-Peer and Cloud Computing systems to achieve the necessary throughput for video-on-demand providers with reduced costs. We propose heuristics that overcome lack of stability in P2P systems by the inclusion of cloud servers into the pool of video streaming servers, avoiding disruptions (stalls) even when the total number of servers are reduced. Simulation results show that the proposed heuristic strategies can help reduce costs while maintaining quality of service.

A compact THz imaging system was developed for the adenocarcinoma-affected human colon tissues measurement simultaneously in transmission and reflection geometry. The contrast between the cancer and control tissues fixed in paraffin at 0.6 THz frequency was up to 23%.

Any digital device generates information that may become valuable evidence in the event of a cybercrime incident, security incident, or cyber-attack, but often the collection, management and preservation of this information is not done properly. In the legal field, once information has been obtained from the devices, it is very important to maintain it and preserve it from the initial time, through investigation, until the trial or investigation is concluded, and to preserve it for long term use, in order to avoid it to be tainted, damaged, changed or manipulated and so assuring reliability through the whole process. Preservation of digital evidence is an important aspect when deciding its admissibility in a trial in process, or in any future process, reopened by appeal, or as source of historical information. This paper contains a review of the state of the art about digital preservation in institutions dedicated to criminal investigation, analyzing concepts, related projects, tools and legal support in this area. The motivation of this paper is the idea of finding how close we are to having a framework useful to preserve digital evidence, ensuring integrity, hence increasing its admissibility, and supported by long term preservation technique.

Wireless stimulation of neural tissue could enable many emerging neural prosthesis designs, and eliminate problems associated with percutaneous wires and connectors. Our laboratory has developed a 16-channel wireless floating microelectrode array (WFMA) for chronic implantation. Here, we report on its first use within in-vivo experiments, using a rat sciatic nerve model. Stimulus currents and associated muscular movements were determined for electrodes of two WFMA devices implanted into four animal subjects.

The compact light weight SATRAM payload is operating in onboard ESA's Proba-V satellite in low Earth orbit since May 2013. Equipped with the Timepix detector the device can determine the composition and spectral characteristics of ionizing radiation (X-ray, light and heavy charged particles) in the satellite environment. Single quantum counting capability and per-pixel energy sensitivity enable quantum-level detection, high resolution tracking, LET sensitivity and directional visualization of energetic charged particles over a wide dynamic range of particle fluxes, energies and wide field of view. A description of the payload is presented together with preliminary data results such as spatial and time correlated maps of dose rate along the satellite orbit.

In low-energy nuclear reactions of astrophysical and fusion interest the spatial- and time-correlated detection of two and more reaction products can be a useful tool to discern reaction mechanisms such as investigate reaction channels, measure angular distributions of reaction products and determine partial reaction widths. For this purpose we assembled a configurable array of Timepix detectors with trigger and synchronized readout by a custom-made coincidence unit. The instrumentation, developed and tested for detection of fission fragments in spontaneous and neutron induced fission, has been extended to low-energy light-ion induced reactions. Application and demonstration of the technique with two Timepix detectors on p+p elastic scattering and on the reaction 11B(p,α)αα at the Van de Graaff (VdG) accelerator in Prague and the Tandem VdG accelerator of the KINR in Kiev, respectively, are presented.

Health-related quality of life (HR-QoL) is a subjective concept, reflecting the overall mental and physical state of the patient, and their own sense of well-being. Estimating current and future QoL has become a major outcome in the evaluation of critically ill patients. The aim of this study is to enhance the inference process of 6 weeks and 6 months prognosis of QoL after intensive care unit (ICU) stay, using the EQ-5D questionnaire. The main outcomes of the study were the EQ-5D five main dimensions: mobility, self-care, usual activities, pain and anxiety depression. For each outcome, three Bayesian classifiers were built and validated with 10-fold cross-validation. Sixty and 473 patients (6 weeks and 6 months, respectively) were included. Overall, 6 months QoL is higher than 6 weeks, with the probability of absence of problems ranging from 31% (6 weeks mobility) to 72% (6 months self-care). Bayesian models achieved prognosis accuracies of 56% (6 months, anxiety depression) up to 80% (6 weeks, mobility). The prognosis inference process for an individual patient was enhanced with the visual analysis of the models, showing that women, elderly, or people with longer ICU stay have higher risk of QoL problems at 6 weeks. Likewise, for the 6 months prognosis, a higher APACHE II severity score also leads to a higher risk of problems, except for anxiety depression where the youngest and active have increased risk. Bayesian networks are competitive with less descriptive strategies, improve the inference process by incorporating domain knowledge and present a more interpretable model. The relationships among different factors extracted by the Bayesian models are in accordance with those collected by previous state-of-the-art literature, hence showing their usability as inference model.

We report on the first prototypes of hybrid detectors for neutrons from the INFN HYDE project. Devices consist of 3D silicon sensors coupled to PolySiloxane-based converters. The sensor design and fabrication technology are presented, along with initial results from the functional characterization of the devices in response to radioactive sources and neutron beams of different energies.

This work reports the study of an attractive interfacial wave for application in ultrasonic NDE techniques for inspection and fluid characterization. This wave, called quasi-Scholte mode, is a kind of flexural wave in a plate in contact with a fluid which presents a good sensitivity to the fluid properties. In order to explore this feature, the phase velocity curve of quasi-Scholte mode is experimentally measured in a plate in contact with a viscous fluid, showing a good agreement with theory.

Radiotherapy with carbon ion beams is a highly precise method for cancer treatment. This is due to the finite range and the relatively low lateral scattering of the carbon ions in comparison to protons. On their path through tissue, the carbon ions can undergo nuclear fragmentation, resulting in lighter projectile fragments. Since the biological effect of the fragments differs from the primary particles, it is important to consider fragmentation in beam models used for therapy planning. Until now, large apparatus have been utilized for ion spectroscopic measurements. Employing a small detector would allow investigations directly within therapy relevant phantoms. In this contribution we report on the development of such a method using the Timepix detector. Its high spatial resolution enables to visualize and distinguish tracks of single particles. Experiments were performed at the Heidelberg Ion-Beam Therapy Center, using a carbon ion pencil beam of E=271 MeV/u. To investigate fragments in different material depths, the detector was placed perpendicular to the beam with 12 to 45 cm thick PMMA slabs in front of it. The pixel-wise energy calibration allows to directly determine the particle energy loss in the sensitive layer. Charge released in the detector by an ion spreads out during charge collection and is collected by several adjacent pixels forming signal clusters. Pattern recognition analysis of the signal shows a clear dependence of cluster parameter distributions on the PMMA depth. Based on this information the particular particle species in the obtained spectra could be identified. In this way, discrimination between primary carbon ions and hydrogen, helium and heavier fragments is possible. The presented novel method enables fragment distinction in mixed particle fields. Its main advantage lies in the flexibility and small size of the set-up.

The finite range of ion beams in matter and the presence of the Bragg-peak at the end of their range enable to create highly localized dose distributions. This advantage represents at the same time a challenge - namely to control all factors influencing the dose distribution with high precision. To ensure the required quality of the dose distribution applied to the patient, a number of measurement procedures is conducted. Many of these techniques were adopted from photon beam radiotherapy. Improvements in terms of the information amount gained are expected from new generations of dedicated ion detection techniques. One of the possible research directions is given by semiconductor-based detectors, which are at present rarely used in ion beam radiotherapy. In this contribution we report on the studies of the capabilities of the Timepix detector. This hybrid semiconductor pixelated detector was developed by the Medipix Collaboration at CERN. Its high spatial resolution allows an online registration of single ions. Experiments were performed at the Heidelberg Ion Beam Therapy Center in Germany using carbon ion beams. The signal pattern of single ions in the detector signal was shown to provide separation of the primary and different types of secondary ions. The direction of the secondary ions emerging from different irradiated phantoms were measured using 3D voxel detector containing several Timepix layers. The analysis of the recorded ion tracks shows a correlation with the beam range, position and width, which are all of high interest for monitoring of the beam within the patient during the therapy delivery. The results of the discussed studies show that the Timepix detector offers attractive capabilities for the needs of carbon ion beam therapy.

For studies of astrophysical interest and nuclear reactions with radioactive nuclei, charged particle products emitted from nuclear reactions such as 7Li + 9Be are routinely produced, separated and focused onto a focal spot by ion focusing separators such as a superconducting solenoid. The separation and focusing of desired ion groups onto the focal plane is however not complete, being also accompanied by unwanted ion groups. The mass- and energy-resolving but also the spatial focusing power of these separators are also limited and often spread out. In order to evaluate and determine and minimize these effects we decided to analyze the spectral and spatial distributions of ion reaction products at a superconducting solenoid. For this purpose we use the position-sensitive quantum-counting pixel detector Timepix which provides energy or time sensitivity per pixel. This device resolves different ion groups and measures the spectral and spatial spread distributions. Single ions are detected and individual ion groups can be identified and distinguished by multi-parameter event-by-event and pattern recognition analysis of the characteristic ion signal response in the pixelated detector. We present the capabilities of the technique on the indicated reaction above which is studied at the radioactive ion beam facility RIBRAS in Brazil. Several ion groups arriving at the focal plane are established such as 7,8Li, 4,6He and 3H together with their spatial and spectral distributions. The energy- and spatial-spread of the solenoid resolving power at the focal plane can be thus evaluated with a resolution of tens of keV and few µm, respectively. The detector serves moreover as an online verification and calibration imager for the ion optics separator and beam focusing monitoring. Results are presented for measurements with a 24 MeV 7Li beam and a thin 9Be target with the solenoid tuned for selection and focusing of produced radioactive 8Li.

In this work we present the technique enabling visualization of the field of scattered and secondary ions generated by primary beam. The technique uses a small 3D sensitive voxel detector composed of several layers of Timepix pixel detectors. The device is placed close to the irradiated object (outside of the primary ion beam) recording the traces of all radiation coming from the sample. Detector provides the timestamp and/or deposited energy for each single particle. The shapes of traces are very typical for different particles which allows for separation of ions from other background such as electrons and gamma photons. The 3D information form the voxel detector allows for reconstruction of direction of incoming radiation. Therefore it is possible to distinguish whether particle came with the beam or it was generated or scattered later. The back projection of reconstructed directions for all registered ions can be in suitable geometry used for generation of image of distribution of scattering or fragmentation in the volume of the irradiated object. The initial experimental study to register the out coming ion radiation from testing phantom was performed at the Heidelberg Ion Beam Therapy Center (HIT) in Germany using medical carbon ion beam.

For the study and detection of neutrons in space environments such as planetary and earth orbiting missions semiconductor silicon diode detectors have been characterized and calibrated at various thermal neutron sources. Two types of diodes adapted for thermal neutron detection were investigated: silicon MESA planar detectors equipped with thin 6LiF layers and silicon heterodiodes with a layer of natural boron or enriched 10B. The response and absolute detection efficiency have been measured. The influence of bias voltage and converter layer thickness were studied. As neutron sources we used a homogenous isotropic thermal neutron field by a set of PuBe radionuclide sources placed in a graphite pile as well as a parallel thermal neutron beam with high Cd ratio (105) and suppressed gamma background. Depending on the converter layer thickness and/or boron layer thickness as well as the choice of the threshold level, efficiencies of approximately 1% are obtained for both the silicon diodes with thin 6LiF and the boron rich silicon detectors. These values guarantee optimal stability of operation in remote and different environments as well as maximum signal-to-noise ratio by enhanced suppression of unwanted signals and gamma background.

The interaction of proton and hadron beams of relativistic energy in matter is accompanied by the production of penetrating highly energetic secondary particles and nuclear reaction products which can affect the desired highly localized deposition of energy of the primary high LET particles for radiotherapy purposes. The observation of all ionizing particles arising from and accompanying the primary radiation as well as the direct measurement of particle energy loss, trajectory, local energy deposition and lateral straggling can be directly provided by the semiconductor pixel detector Timepix. This device operates as an active nuclear emulsion providing on-line visualization of particle traces. Results of a pilot experiment are presented with proton and carbon ion beams in the energy range 48–220 MeV/u and 88–430 MeV, respectively produced at the Heavy Ion Therapy HIT facility in Heidelberg.

Charged-particle coincidence correlated measurements such as angular correlations between rare and main fission fragments measured with conventional detectors provide only partial and limited information (energy cutoff, narrow range of studied ion Z numbers). Many of these drawbacks arise from the standard solid state detectors used so far which can be solved simultaneously by usage of highly segmented single-quantum counting pixel detectors. The Timepix pixel device, which is equipped with energy and time sensitivity capability per pixel, provides high granularity, wide dynamic range and per pixel threshold. This detector operated with integrated USB-readout interfaces such as the USB 1.0 and FITPix devices and the data acquisition software tool Pixelman, both developed for the pixel detectors of the Medipix-family, enables a variety of instrumental configurations, visualization, real-time event-by-event selection as well as vacuum and portability of operation for flexible measurements on different targets and setups. These features combined with event track analysis provide enhanced signal to noise ratio with a high suppression of background and unwanted events. The detector provides multi-parameter information (position, energy and time) for basically all types of ionizing particles in a wide dynamic range of energy (pixel energy threshold ≈ 4 keV), interaction/arrival time (timepix clock step ≥ 100 ns) and position (pixel size = 55 μm). High selectivity is achieved by spatial and time correlation in the same sensor. In addition, several detectors can be run in coincidence. The open and close exposition (shutter) time as well as the readout DAQ can be fully synchronized. For this purpose, we have assembled a modular multi-parameter, tunable and extendable coincidence detector array system based on two and more Timepix devices which can be coupled with supplementary detectors (solid state ΔE detectors and/or ionization chambers) for enhanced ion selectivity. We describe the individual configurations and techniques together with the experiments carried out at several neutron beam/source facilities. We summarize the results and capabilities of application.

We present a methodology to accurately locate persons indoors by fusing Inertial Navigation (INS) techniques with active RFID technology. A foot-mounted IMU aided by the Received Signal Strengths (RSS) obtained from several active RFID tags, placed at known locations in a building, has been used. Other authors have already integrated IMUs with RFID tags in loosely-coupled Kalman Filter (KF) solutions [1], [2], [3]. They feed the KF with the residuals of inertial- and RFID-calculated positions; these approaches do not exploit the benefits of Zero Velocity Updates (ZUPT). In this paper, we present a tight KF-based INS/RFID integration using the residual between the INS-predicted range-to-tag, and the range derived from a generic RSS path-loss model. Our approach also includes ZUPTs at detected foot stances, ZARU (Zero Angular-rate Update) estimation at still phases, and heading drift reduction using magnetometers. A 15-element error state Extended KF [4], [7] compensates position, velocity and attitude errors of the INS solution, as well as IMU biases. This methodology is valid for any kind of motion (forward, lateral or backwards walk, at different speeds) and does not require an specific off-line calibration, neither for the user gait, nor for the location-dependent RSS fading in the building. The integrated INS+RFID methodology eliminates the typical drift of IMU-alone solutions (approximately 1% of the total travelled distance), accounting for typical positioning errors along the walking path (no matter its length) of approximately 1.5 meters.