Wirelessly Powered Backscatter Communications: Waveform Design and SNR-Energy Tradeoff

This paper shows that wirelessly powered backscatter communications is subject to a fundamental tradeoff between the harvested energy at the tag and the reliability of the backscatter communication, measured in terms of SNR at the reader. Assuming the RF transmit signal is a multisine waveform adaptive to the channel state information, we derive a systematic approach to optimize the transmit waveform weights (amplitudes and phases) in order to enlarge as much as possible the SNRenergy region. Performance evaluations confirm the significant benefits of using multiple frequency components in the adaptive transmit multisine waveform to exploit the nonlinearity of the rectifier and a frequency diversity gain.Comment: submitted for publicatio

Teacher self-esteem, self-efficacy and perception of school context as predictors of professional burnout

This study had two major objectives: (1) to examine the relationship between self-efficacy, self-esteem, school climate, and teacher burnout in an Iranian sample and (2) to examine to what extend self-efficacy, self-esteem, school climate predict burnout among secondary school teachers. Participants of this study were 280 (147 female, 143 male) teachers. They completed the Maslach Burnout Inventory – Educator’s Survey (MBI-ES, Mashlach, Jackson, & Leiter, 1996), the Rosenberg Self-esteem Scale (Rosenberg, 1965), the Norwegian Teacher Self-Efficacy Scale (NTSES; Skaalvik E., & S. Skaalvik, 2007), and the Teacher’s Perception of the School Context (Skaalvik, 2010). Correlational analyses indicated that self-efficacy, self-esteem, school climate were significantly involved in teacher burnout. The results of multiple regression analysis indicated that burnout was affected differently from three predictor variables

Teacher self-esteem, self-efficacy and perception of school context as predictors of professional burnout

This study had two major objectives: (1) to examine the relationship between self-efficacy, self-esteem, school climate, and teacher burnout in an Iranian sample and (2) to examine to what extend self-efficacy, self-esteem, school climate predict burnout among secondary school teachers. Participants of this study were 280 (147 female, 143 male) teachers. They completed the Maslach Burnout Inventory – Educator’s Survey (MBI-ES, Mashlach, Jackson, & Leiter, 1996), the Rosenberg Self-esteem Scale (Rosenberg, 1965), the Norwegian Teacher Self-Efficacy Scale (NTSES; Skaalvik E., & S. Skaalvik, 2007), and the Teacher’s Perception of the School Context (Skaalvik, 2010). Correlational analyses indicated that self-efficacy, self-esteem, school climate were significantly involved in teacher burnout. The results of multiple regression analysis indicated that burnout was affected differently from three predictor variables

Squeak and Rattle Prediction for Robust Product Development

Squeak and rattle are nonstationary, irregular and impulsive sounds that happen inside the car cabin. For decades, customer complaints about squeak and rattle have been, and still are, among the top quality issues in the automotive industry. These annoying sounds are perceived as quality defect indications and burden warranty costs to the car manufacturers. Today, the quality improvements regarding the persistent type of sounds in the car, as well as the increasing popularity of electric engines, as green and quiet propulsion solutions, stress the necessity for suppressing annoying sounds like squeak and rattle more than in the past. The technical solution to this problem is to approach it in the pre-design-freeze phases of the product development and by employing design-concept-related practises. To nail this goal, prediction and evaluation tools and methods are needed to deal with the squeak and rattle quality issues upfront in the product development process. The available tools and methods for prediction of squeak and rattle sounds in the pre-design-freeze phase in a new car development process are not yet sufficiently mature. The existing knowledge gap about the mechanisms behind the squeak and rattle sounds, the lack of accurate simulation and post-processing methods, as well as the computational cost of complex simulations are some of the significant hurdles in this immaturity. This research addresses this problem by identifying a framework for prediction of squeak and rattle sounds in the form of a cause and effect diagram. The main domains and the elements and the sub-contributors to the problem in each domain within this framework are determined through literature studies, field explorations and the conducted descriptive studies on the subject. Further, improvement suggestions for the squeak and rattle evaluation and prediction methods are proposed through prescriptive studies. The applications of some of the proposed methods in the automotive industry are shown and examined in industrial problems

New Ways of Data Compression and Noiseless Recovery

Viene presentata la teoria del Compressed Sensing, proponendo un nuovo metodo di acquisizione e campionamento di segnali che permette un recupero totale di informazione a partire da un numero molto ridotto di campioni, superando in questo senso i limiti posti dal Teorema di Campionamento di Shannon. Sono poi analizzate possibili applicazioni pratiche, in particolare a tecniche di risonanza magneticaope

Our House

Our House is a short socio-political drama about Anahita, an Iranian refugee in Toronto, who runs into the man who brutally murdered her parents at their home in Tehran years ago. Despite Anahitas attempts in the past to convince the authorities to reject this mans application for immigration, he had nonetheless obtained Canadian Citizenship. The encounter, renews Anahitas tragedy and re-awakens her grief. Failed by the system, she decides to take justice into her own hands

International Legal Responsibility of International Organizations in the ILC Draft Articles and Beyond

The phenomenon of proliferation of international organizations has urged focus on the responsibility of international organizations under international law as the effect of their activities is witnessed everywhere in our daily life. The main purpose of the present book is to examine and review some specific aspects relevant to the question of international legal responsibility of international organizations, mainly, with a view to assessing the International Law Commission’s work on the codification of the international legal rules applicable on international organizations in this area. At the same time, the intention is to address the major challenge to the codification of general rules for international organizations, namely, their wide-varying nature and their differences from each other. Furthermore, the perspective has been enlarged by elaborating on the broader concept of accountability of international organizations