Wind energy harvester interface for sensor nodes

The research topic is developping a power converting interface for the novel FLEHAP wind energy harvester allowing the produced energy to be used for powering small wireless nodes. The harvester\u2019s electrical characteristics were studied and a strategy was developped to control and mainting a maximum power transfer. The electronic power converter interface was designed, containing an AC/DC Buck-Boost converter and controlled with a low power microcontroller. Different prototypes were developped that evolved by reducing the sources of power loss and rendering the system more efficient. The validation of the system was done through simulations in the COSMIC/DITEN lab using generated signals, and then follow-up experiments were conducted with a controllable wind tunnel in the DIFI department University of Genoa. The experiment results proved the functionality of the control algorithm as well as the efficiency that was ramped up by the hardware solutions that were implemented, and generally met the requirement to provide a power source for low-power sensor nodes

Spin wave excitations in a nanowire spin-torque oscillator with perpendicular magnetic anisotropy

Spin torque oscillators (STOs) are emerging microwave devices that can potentially be used in spin-logic devices and the next-generation high-speed computing architecture. Thanks to their non-linear nature, STOs are easily tunable by the magnetic field and the dc current. Spin Hall nano-oscillators (SHNOs) are promising types of STOs and most of the current studies focus on localized modes that can be easily excited. Here, we study using micromagnetic simulations, the nature of the spin-torque-induced excitations in nanowire devices made of perpendicular magnetic anisotropy (PMA) material. Our results showed that upon including PMA the excitation of localized and propagating spin wave modes is feasible. We study the nature of the mode excitations as a function of the PMA strength (\text{K}$_u$), and the current. Indeed, we estimate a critical value of \text{K}$_u$ to allow for the excitation of the propagating spin wave. We attribute this mode selectivity between localized and propagating modes to a switch in the sign of the nonlinearity of the system from negative to positive at a non-zero \text{K}$_u$ which is supported by analytical calculations. Our results provide deep insight into engineering reconfigurable microwave devices for future magnonic and computational applications

Struggling for a right: Islam and the participation in sports and physical recreation of girls and women in Kuwait

This thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel University.The present study is the first of its kind. It is a study about the involvement of Kuwaiti females in sports and physical recreation. The study invesigates both the structures and resources that make female participation in sports and physical recreation possible, and the ideological and physical barriers that prevent girls and young women from taking part. The development of female sports and physical recreation in Kuwait is investigated in relation to relevant historical and political developments, taking particular account of the influence of Islamic ideologies about the role of women in society, women's enfranchisement, and women's bodies. It provides evidence from the Holy Qur'an in support of the need for girls and women to exercise their bodies. The research highlights the contradictory position that Kuwaiti women find themselves in living in a relatively liberal Islamic state with an official discourse of gender equality, but facing traditional and unequal gender divisions in daily life and throughout culture, specifically in sports and physical recreation. Opportunities for females in sports and recreation are tied to the political administration system of the state and the study looks at the present day situation of public provision and resourcing, following the liberation of the country from Iraq, as well as private resources that have developed as a result of westernized, global influences.. The study presents recommendations for Kuwaiti sports policy-makers, planners, and providers - that may be useful, too, for those in other societies in the Arabian Peninsula - concerning sports and physical recreation for Muslim girls and women in the future. The project traces the development of organised sport and physical recreation for females from 1950 until the present day. It includes details of physical education in schools, and the establishment and expansion of sport clubs and other facilities that are now in the country. Reference is made to the role of government agencies and departments - in particular the Public Authority for Youth and Sport (PAYS) that has special responsibility to establish stronger and more specialized opportunities. Since there is virtually no previous research or literature about the topic of girls and young women's involvement in sport and physical recreation in Kuwait, the main method of data collection was through questionnaires and interviews, supported by documentary evidence, including official statements.Public Authority for Applied Education and Training in Kuwai

The Influence of Jodipan Color Utilization as a Learning Source of Ability to Solve Problems in The Theme of Enviromental Pollution

The ability to solve problems is a process in which a person identifies a situation, formulates a hypothesis, verifies a hypothesis made by digging up data, and restarts the hypothesis made to become a generalization (Purwanto, 1999). The focus of this research is to analyze the influence of the use of the Kampung Warna Warni Jodipan as a source of learning for students' ability to solve problems in MTs Attaraqqie Malang on the theme of tackling environmental pollution. This study uses an experimental research design in the form of a Quasi-Experimental Design with the type of pretest posttest control group design. The sample in this study were students of class IX A and IX D with purposive sampling technique. Data collection techniques using test questions in the form of problem description. The data analysis technique in this study was to use the independent sample t-test. The results of this study indicate that there is a significant influence on the use of the Kampung Warna Warni Jodipan as a source of learning for students' problem solving abilities, this is evidenced by the results of the independent sample t-test which shows that there is a significant influence on the use of the Kampung Warna Warni Jodipan. , with tcount> ttable which is 5,450> 2,000. This shows that there are significant differences in the ability to solve problems in the experimental and control classes. &nbsp