316 research outputs found
A Computational Model of Neuroreceptor-Dependent Plasticity (NRDP) Based on Spiking Neural Networks
Natural orbitals and sparsity of quantum mutual information
Natural orbitals, defined in electronic structure and quantum chemistry as
the (molecular) orbitals diagonalizing the one-particle reduced density matrix
of the ground state, have been conjectured for decades to be the perfect
reference orbitals to describe electron correlation. In the present work we
applied the Wavefunction-Adapted Hamiltonian Through Orbital Rotation (WAHTOR)
method to study correlated empirical ans\"atze for quantum computing. In all
representative molecules considered, we show that the converged orbitals are
coinciding with natural orbitals. Interestingly, the resulting quantum mutual
information matrix built on such orbitals is also maximally sparse, providing a
clear picture that such orbital choice is indeed able to provide the optimal
basis to describe electron correlation. The correlation is therefore encoded in
a smaller number of qubit pairs contributing to the quantum mutual information
matrix.Comment: 11 pages + supplementary meteria
Sviluppo E Confronto Di Strumenti Di Prova Per Sensori D'Immagine
Questa Tesi descrive la progettazione e lo sviluppo di un sistema d'illuminazione a LED destinato alla verifica e alla caratterizzazione di sensori d'immagine, esaminando le problematiche emerse sia in fase di progettazione, che nella fase di test successiva alla realizzazione dei prototipi. Al fine di realizzare uno strumento che garantisse un'elevata precisione ed accuratezza, è stata analizzata e parametrizzata la caratteristica dei LED al variare delle condizioni di funzionamento. Si è proceduto a sperimentare e a confrontare varie tecniche di pilotaggio; i risultati sono esposti nella sezione finale di questo lavoro, che evidenzia pregi e difetti di ogni soluzione. Il sistema inizialmente progettato era affetto da alcune criticità, prevalentemente di natura termica, che ne rendevano difficoltoso l'utilizzo. Queste problematiche sono state in buona parte superate introducendo un sistema di retroazione, ottenendo un sistema molto più semplice da utilizzare e che fornisce risultati estremamente ripetibili.
This thesis describes the design and development of a LED lighting system aimed to the verification and characterization of image sensors, starting from design issues up to the prototype testing phase. LED characteristics have been examined under many working conditions, in order to design a precision instrument. Some different driving techniques have been exploited and compared. The results are presented in the final section of this work, comparing benefits and flaws of each solution. The system was initially affected by well-known defects, mainly due to thermal drift, unfavourably impacting on usability and long-term repeatability. Those issues have been mostly superseded using a dedicated feedback system, resulting in a new instrument, by far more accurate and easier to operate
Curve e superfici di suddivisione con applicazione alle immagini digitali
Dopo aver definito tutte le proprietà, si classificano gli schemi di suddivisione per curve. Si propongono, quindi, degli schemi univariati per la compressione di segnali e degli schemi bivariati per lo scaling e la compressione di immagini digitali
El niño abusado se convierte en adulto: reflexiones sobre algunos casos tratados
Este artículo es la traducción del titulado “Il bambino abusato diventa adulto”, publicado en el número 91 de la revista Terapia Familiare (noviembre 2009, páginas 161-182). Traducción de Valentina Capecci, Gonzalo del Moral
y Miguel Garrido.El autor analiza algunos casos clínicos para reflexionar sobre diferentes resultados
que la experiencia del abuso sexual sufrido en la infancia puede tener en la influencia del
desarrollo de un sujeto de sexo masculino. Se proponen tres distintas posibilidades que se
pueden detectar en la población clínica. La clásica trasformación de víctima a agresor, la
persistencia, por el contrario, en la posición de víctima y aquella del espectador relativa
a los hermanos varones de víctimas de sexo femenino. Los recursos ofrecidos por el
modelo de apego (ofrecido por el progenitor protector, y también por el mismo abusador)
en relación a la dimensión del miedo suscitado por el evento traumático juegan un papel
determinante en la dirección que puede tomar la evolución del niño abusado.The author analyzes some cases clinicians to reflect on different results than the
experience of the sexual abuse suffered in childhood can have on the influence of
development of a male subject. Proposed three different possibilities that are they can
detect in the clinical population. The classical transformation of victim to aggressor, the
persistence, on the contrary, in the position of victim and one the relative to the victims
of female male brothers spectator. The resources offered by the attachment (offered by
the parent) model (guard, and also by the same abuser) in relation to the dimension of
the fear aroused by the traumatic event play a decisive role in the address that can take
the evolution of the abused child
A smartphone-based architecture to detect and quantify freezing of gait in Parkinson’s disease
Introduction
The freezing of gait (FOG) is a common and highly distressing motor symptom in patients with Parkinson’s Disease
(PD). Effective management of FOG is difficult given its episodic nature, heterogeneous manifestation and limited responsiveness
to drug treatment.
Methods
In order to verify the acceptance of a smartphone-based architecture and its reliability at detecting FOG in real-time,
we studied 20 patients suffering from PD-related FOG. They were asked to perform video-recorded Timed Up and Go
(TUG) test with and without dual-tasks while wearing the smartphone. Video and accelerometer recordings were synchronized
in order to assess the reliability of the FOG detection system as compared to the judgement of the clinicians
assessing the videos. The architecture uses two different algorithms, one applying the Freezing and Energy Index
(Moore-Bächlin Algorithm), and the other adding information about step cadence, to algorithm 1.
Results
A total 98 FOG events were recognized by clinicians based on video recordings, while only 7 FOG events were
missed by the application. Sensitivity and specificity were 70.1% and 84.1%, respectively, for the Moore-Bächlin Algorithm,
rising to 87.57% and 94.97%, respectively, for algorithm 2 (McNemar value = 28.42; p = 0.0073).
Conclusion
Results confirm previous data on the reliability of Moore-Bächlin Algorithm, while indicating that the evolution of
this architecture can identify FOG episodes with higher sensitivity and specificity. An acceptable, reliable and easy-to-implement
FOG detection system can support a better quantification of the phenomenon and hence provide data useful to
ascertain the efficacy of therapeutic approaches
An instrument for the characterization and calibration of optical sensors
This paper presents the development of a hardware/software system for the characterization of the electronic response of optical (camera) sensors such as matrix and linear color and monochrome Charge Coupled Device (CCD) or Complementary Metal Oxide Semiconductor (CMOS). The electronic response of a sensor is required for inspection purposes. It also allows the design and calibration of the integrating device to achieve the desired performance. The proposed instrument equipment fulfills the most recent European Machine Vision Association (EMVA) 1288 standard ver. 3.1: The spatial non uniformity of the illumination ΔE must be under 3%, and the sensor must achieve an f-number of 8.0 concerning the light source. The following main innovations have achieved this: An Ulbricht sphere providing a uniform light distribution (irradiation) of 99.54%; an innovative illuminator with proper positioning of color Light Emitting Diodes (LEDs) and control electronics; and a flexible C# program to analyze the sensor parameters, namely Quantum Efficiency, Overall System Gain, Temporal Dark Noise, Dark Signal Non Uniformity (DSNU1288), Photo Response Non-Uniformity (PRNU1288), Maximum achievable Signal to Noise Ratio (SNRmax), Absolute sensitivity threshold, Saturation Capacity, Dynamic Range, and Dark Current. This new instrument has allowed a camera manufacturer to design, integrate, and inspect numerous devices and camera models (Necta, Celera, and Aria)
The KIMORE dataset: KInematic assessment of MOvement and clinical scores for remote monitoring of physical REhabilitation
The paper proposes a free dataset, available at the following link1, named KIMORE, regarding different rehabilitation exercises collected by a RGB-D sensor. Three data inputs including RGB, Depth videos and skeleton joint positions were recorded during five physical exercises, specific for low back pain and accurately selected by physicians. For each exercise, the dataset also provides a set of features, specifically defined by the physicians, and relevant to describe its scope. These features, validated with respect to a stereophotogrammetric system, can be analyzed to compute a score for the subject's performance. The dataset also contains an evaluation of the same performance provided by the clinicians, through a clinical questionnaire. The impact of KIMORE has been analyzed by comparing the output obtained by an example of rule and template-based approaches and the clinical score. The dataset presented is intended to be used as a benchmark for human movement assessment in a rehabilitation scenario in order to test the effectiveness and the reliability of different computational approaches. Unlike other existing datasets, the KIMORE merges a large heterogeneous population of 78 subjects, divided into 2 groups with 44 healthy subjects and 34 with motor dysfunctions. It provides the most clinically-relevant features and the clinical score for each exercise
Prototipo de asistencia indoor dentro de un supermercado
La mayoría de las aplicaciones móviles de asistencia indoor en supermercados son creadas ad hoc, es decir, no cuentan con un modelo asociado para definir la información de los productos o servicios que brindan. Esta es una de las motivaciones de esta tesis, y acorde a esto, se plantea un modelo de solución en el dominio de los supermercados. En el modelo propuesto, los elementos del supermercado (productos, góndolas y sectores) tienen posiciones específicas dentro del mismo. Las góndolas y los sectores son definidos con un área mientras que los productos estarán ubicados dentro de una góndola. Esto permite brindar precisión en la asistencia, por ejemplo, mostrar que un producto está en el estante dos de una góndola.
En base al modelo propuesto, se desarrolló un prototipo funcional que usa códigos QR para identificar los elementos del supermercado. El usuario es asistido para poder realizar su lista de compras, se le brindan caminos desde su posición actual hasta el siguiente elemento en su lista. Cada vez que el usuario lee códigos QR se le actualiza su posición, y en el caso de ser necesario, se recalcula su camino.Facultad de Informátic
- …