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Novel fuzzy logic controllers with self-tuning capability
No full textTwo controllers which extend the PD+I fuzzy logic controller to deal with the plant having time varying nonlinear dynamics are proposed. The adaptation ability of the first self tuning PD+I fuzzy logic controller (STPD+I_31) is achieved by adjusting the output scaling factor automatically thereby contributing to significant improvement in performance. Second controller (STPD+I_9) is the simplified version of STPD+I_31 which is designed under the imposed constraint that allows only minimum number of rules in the rule bases. The proposed controllers are compared with two classical nonlinear controllers: the pole placement self tuning PID controller and sliding mode controller. All the controllers are applied to the two-links revolute robot for the tracking control. The tracking performance of STPD+I_31 and STPD+I_9 are much better than the pole placement self tuning PID controller during high speed motions while the performance are comparable at low and medium speed. In addition, STPD+I_31 and STPD+I_9 outperform sliding mode controller using same method of comparison study
ROTATIONAL MOTION TRIBOELECTRIC NANOGENERATORS (TENG)
No full textThe triboelectric nanogenerator (TENG) experiments conducted for this research are a continuation of previous research at the Naval Postgraduate School in Monterey, California. Teflon and copper were used as the primary materials to generate electricity through contact. Teflon tape, copper tape, and a variety of readily available materials were used to reduce the cost and increase the viability of mass production. The TENG consists of three parts: a flexible plastic in which the copper tape is applied, a PVC pipe in which the Teflon tape is applied, and a wooden shaft that supports and rotates the PVC pipe with the flexible plastic wrapped around the pipe. A DC motor is connected to the wooden shaft to generate rotational motion for the TENG, causing a potential change within the copper taping configuration. Five TENG models were analyzed for their capability to store and discharge electricity through capacitors and LEDs. The chosen model was also adapted to a stationary bicycle to demonstrate its capability to independently generate electricity.Approved for public release. distribution is unlimitedOutstanding ThesisLieutenant, United States Nav
The Advances in Conversion Techniques in Triboelectric Energy Harvesting: A Review
No full textA triboelectric nanogenerator (TENG) is a new transducer utilizing contact electrification and electrostatic induction to transform mechanical energy into electric energy. Due to its high energy density and flexibility, it can be employed to make electronic devices self-powered by harvesting ambient mechanical energy in many application scenarios, such as biomedical devices, wearable electronics, and Internet-of-Things (IoT) sensors. However, due to the time-varying and low internal capacitance of a TENG, it is challenging to extract electrical energy from it. Hence, good power conversion techniques are crucial in TENG energy harvesting systems. Currently, studies on dedicated integrated power conversion techniques are very limited. Due to the exponentially increasing research interests in TENG, a comprehensive study on the TENG energy harvesting system, emphasizing integrated-circuit (IC) power conversion techniques, is urgently needed. This paper summarizes and compares the state-of-the-art triboelectric energy harvesting systems, focusing on different power conversion techniques for output power enhancement. Some techniques, which have been widely used in other relevant energy harvesting systems, are also mentioned to inspire innovative design strategies for TENG systems.Green Open Access added to TU Delft Institutional Repository 'You share, we take care!' - Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.Electronic Components, Technology and MaterialsElectronic Instrumentatio
TRIBOELECTRIC NANOGENERATORS (TENG) WITH ROTATIONAL MOTION
No full textFossil fuels produce most of the world’s energy. They have a high energy density, but they release greenhouse gases and are a limited resource. Renewable energy is a relatively new concept that produces low to zero emissions and consists of a variety of methods such as solar, wind, and hydroelectric energy. While the ocean is a very large resource, there is limited research in harvesting energy from it. This research develops and tests a triboelectric nanogenerator (TENG) using rotational motion at the Naval Postgraduate School (NPS). The concept follows previous experiments at NPS with friction between PTFE and copper. The cost and production are reduced by using copper foil tape and PTFE tape and 3D printing the TENG components. The TENG consists of three parts: a top half shell containing half of the copper electrodes, a bottom half containing the other half of the copper electrodes, and an inner rod with PTFE tape. The inner rod is connected to a DC motor and run at various speeds to determine the most effective output voltage and current.Approved for public release; distribution is unlimited.Lieutenant, United States Navyhttp://archive.org/details/triboelectricnan109456491
Using ICA for Retrieving Teng Parameters
No full textThe blind source separation (BSS) method of Independent Component Analysis (ICA) is explored as a new approach for the reconstruction of the transfer matrix of Linear Coupling Parameterization. ICA is a method to detangle independent signals out of several measurements of their mixtures. In BSS-calculations, it is usually not possible to retrieve the mixing matrix, for the source signals, as well as the matrix, are unknown. Combining the parameterization model of D.A. Edwards and L.C. Teng with the standard ICA approach, it is though possible to retrieve the mixing matrix, as the form of the original uncoupled motion is known. At the same time arises the possibility to recalculate the parameters of Edwards and Teng through a system of equations of the one turn map components. It can be shown as a proof of concept, that the parameters can be reconstructed up to high accuracy for a simulated, non-perturbed signal
The relationship between the exercise of political power and language during the cultural revolution in Inner Mongolia - 1967-1969
No full textThis is an analysis of the relationship between language contained in political documents and the exercise of power and authority from the Cultural Revolution in the Inner Mongolian Autonomous Region of the People's Republic of China from 1967 to 1969. It is based on analytic methods found in the works of Foucault, Bourdieu, Gramsci and others. The material analysed falls into four periods. The
first phase in 1967 saw the initial impact of the CR manifesting itself locally by causing conflict between two key entities in the IMAR - the army and student rebellion groups. The response by the Centre to this was the conduct of dialogues with the local groups, resulting in the issuing of a key document, the '13th April Decision,' to 'resolve' the local problems and impose hegemony from the Centre, through promoting standardised narratives and a specific ideology - CR Maoism. The -second phase from 1967 to 1968 saw the implementation of this strategy through the attack on the local leader, Ulanfu. During this period the discourse to 'handle' the region was articulated promoting a narrative and ideology from the Centre in Beijing of power based on class, excluding any assertions of the primacy of ethnicity and nationality locally. The third phase from 1968 to 1969 saw the promotion by the Centre of the newly installed leader, Teng Haiqing, using this new discourse. In this period, a local enemy - the Inner Mongolian People's Party - was gradually articulated. The final phase in 1969 saw the social turmoil and violence caused by the purge of those claimed to be members of this party, and the withdrawal of support from the Centre for Teng Haiqing, resulting in his use of a self-critical language, the creation of an adapted narrative and ideology, conveyed through a new discourse in which the key issues of class and ethnicity/nationality were approached in different ways.
The focus of this thesis is the signification of power in language and discourse through this period, and the techniques by which to describe and understand this
Division and Unity: The History and Historiography of the Pennsylvania Constitution
No full textAbout the author:
Wen Li Teng is pursuing a double major in History and Political Science at the University of Chicago
Evaluation of oxygen bomb methodology for studying frying chemistry
No full textOxipresTM oxygen bomb instrumentation was evaluated for measuring oxygen consumption in studying reactions of food oils at frying temperatures. High oleic sunflower oil:corn oil blends (60:40 w/w) were heated in OxipresTM cells over a range of temperatures from 100 to 180 °C under different gases and pressures. Effects of sample size, temperature, pressure, pressurizing gas, heating time, mixing, and oil characteristics were determined. Conjugated dienes, peroxide values, aldehydes, and free fatty acids were measured to relate oxygen consumption curves to other chemical changes during lipid oxidation. At 150 °C and above, oxygen consumption exhibited no induction periods and did not follow Arrhenius kinetics. Curves showed an initial pressure increase associated with oil heating, followed by a period of rapid decline, then a slowing in pressure decrease with continued heating. Limitations of oxygen diffusion may contribute to but do not fully explain this decreasing reactivity. Oxygen consumption rates and net uptake increased with headspace oxygen concentration (2, 5, 20, and 100%) and pressure (0.5 to 5 bars). The system accurately differentiated oxidation sensitivity of oils with different degrees of unsaturation with high reproducibility (average variation 2.27%). Oxygen consumption correlated with aldehyde oxidation products, particularly under high oxygen, but not conjugated dienes or hydroperoxides. Patterns of volatile products collected by short path thermal ii desorption tubes connected to Oxipres cells showed a homologous series of C2-C12 alkanes, alkenes, fatty acids, and aldehydes. These products are more consistent with thermal scission reactions than lipid autoxidation initiated by pre-formed hydroperoxides. Overall, the Oxipres system provides very stable, sensitive control of pressure and temperature, but three modifications would improve its design. At frying temperatures, headspace pressure reflects oxygen consumption balanced against release of volatile products and oxygen produced in reactions. Replacing the current pressure transducer with an oxygen-specific sensor would eliminate complications from volatile products. The closed system with slow eddy currents in the oil is a useful research tool but does not accurately model real-life frying. Addition of a stirring mechanism would facilitate oxygen diffusion. Finally, a thermocouple to monitor the actual oil temperature and rates of heating would be very useful.M.S.Includes bibliographical referencesby Teng Pen
Electron Transfer in Contact Electrification under Different Atmospheres Packaged inside TENG
No full textContact electrification (CE), a common physical phenomenon, is worth discussing. However, there are few reports on the influence of atmosphere on CE, or on the performance of triboelectric nanogenerators (TENG), based on CE by encapsulating gas inside. Here, we propose physical processes of electron transfer to interpret the impact of the gaseous atmosphere on CE. An atmosphere-filled triboelectric nanogenerator (AF-TENG) encapsulated five different gas-components of air based on the vertical contact separation mode was prepared. The sensitivity (1.02 V·N−1) and the power density (9.63 μW·m−2) of the oxygen-atmosphere-filled AF-TENG were 229.03% and 157.81% higher than these (0.31 V·N−1 and 3.84 μW·m−2) of the nitrogen-atmosphere-filled AF-TENG. As the oxygen atom possesses more atomic energy levels than other atoms, this could act as a “bridge” for more electrons to directly transfer between the two materials. The device package under different atmospheres could not only strengthen understanding of CE and improve the performance of TENG, but also be potentially applicable to prevent and control unnecessary damage caused by static electricity
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