Modular Piezoresistive Smart Textile for State Estimation of Cloths

Smart textiles have found numerous applications ranging from health monitoring to smart homes. Their main allure is their flexibility, which allows for seamless integration of sensing in everyday objects like clothing. The application domain also includes robotics; smart textiles have been used to improve human-robot interaction, to solve the problem of state estimation of soft robots, and for state estimation to enable learning of robotic manipulation of textiles. The latter application provides an alternative to computationally expensive vision-based pipelines and we believe it is the key to accelerate robotic learning of textile manipulation. Current smart textiles, however, maintain wired connections to external units, which impedes robotic manipulation, and lack modularity to facilitate state estimation of large cloths. In this work, we propose an open-source, fully wireless, highly flexible, light, and modular version of a piezoresistive smart textile. Its output stability was experimentally quantified and determined to be sufficient for classification tasks. Its functionality as a state sensor for larger cloths was also verified in a classification task where two of the smart textiles were sewn onto a piece of clothing of which three states are defined. The modular smart textile system was able to recognize these states with average per-class F1-scores ranging from 85.7 to 94.6% with a basic linear classifier.

A comparative study of structural, mechanical and electrical properties of ZnO and AlN thin films for MEMS based piezoelectric sensors

In this work, a comparative study has been carried out to compare the relative performance of ZnO (Zinc Oxide) and AlN (Aluminum Nitride) thin films for their application in piezoelectric sensors. The thin films material properties are being characterized using various material characterization techniques such as SEM, XRD, and Nanoindentation. Further the MIM (Metal-Insulator-Metal) based devices have been fabricated with piezoelectric films sandwiched between Al electrodes. The devices have been evaluated for mechanical and electrical performances. The natural frequency of the devices recorded as 46.8 kHz (ZnO) and 40.8 kHz (AlN). The average nominal capacitance of the MIM structure is measured as ~98pF and ~120pF where as corresponding dissipation factor obtained as ~0.03 and ~0.0005 respectively for ZnO and AlN devices. The repeatability investigation carried out on the sample devices for up to 90 days and the output has been monitored. The result showed that the AlN devices exhibit better output stability compared to ZnO devices.

Intelligent Control for Pressurizer System in Nuclear Power Plants

Fine control of output power for nuclear power plants is the essential goal for safe operation. In this work, a Fuzzy analytical proportional-integral-derivative (FPID) controller with different configurations is designed to adjust and control the pressure of the PZR system. The stability analysis of the FPID controller with variable gains is established, and conditions for bounded-input bounded-output stability conditions (BIBO) are derived using the small gain theory. Two scenarios are applied for evaluating the dynamic response of applied controllers. In addition, performance indices are compared between the PZR model and data measured from the PCtran VVER-1200 simulator. Finally, a simulation platform is developed for MATLAB / Simulink to implement the three-region nonlinear non-equilibrium PZR model and the designed pressure controllers. The analysis and evaluation results showed good durability of the designed controllers and satisfactory performance of the control. These results further show that the nonlinear PZR model is accurate, feasible, and valuable for dynamic simulation and control unit design.

Study on control strategy of output stability of wind-solar reservoir thermal system

In view of the landscape reservoir heat output coordinated control demand, based on the topology of the hybrid energy storage system of the three ports heating model, using the sunlight with the electricity output of the complementary and heat accumulation can be regulatory, intends to research a kind of based on photo-thermal storage heat and scenery electricity heating output port control method, in order to achieve the goal of fast and smooth regulating heat output fluctuations, The coordinated output control of integrated wind-landscape storage and heat collection is realized.

Design and research of hydraulic conversion system of wave energy generating device

Taking the hydraulic conversion system of the oscillating flapping-wing wave energy power generation device as the research object, a hydraulic conversion system is designed to convert wave energy into usable mechanical energy. Based on the principle of high-efficiency collection of wave energy and stable output of the hydraulic conversion system, the composition of the hydraulic conversion system and the parameters of each component are determined. According to different sea conditions, the pre-charge pressure of the accumulator is adjusted to keep the pressure of the high and low pipelines of the hydraulic system stable, and the mechanical energy is stably output through the hydraulic motor. The AMESim simulation platform is used to build the model of acquisition mechanism and hydraulic conversion system, simulate the motion response of acquisition mechanism under actual sea conditions as the system input, and analyze the effectiveness and output stability of hydraulic conversion system. The results verify that the designed hydraulic conversion system can achieve efficient collection of wave energy. The research results have laid a theoretical foundation for the development and research of wave energy power generation devices.

MODELING THE NONLINEAR FISCAL REACTION FUNCTION IN MALAYSIA

The fiscal reaction function (FRF) provides valuable insights into a country’s fiscal sustainability and output stability. However, there is no consensus yet on how to model it. Thus, this study investigates the best functional form for the FRF by adopting a nonlinear autoregressive distributed lag approach that accounts for a potential structural break in the data across periods. We examine the case of Malaysia and address the country’s data by using a break-point of the unit root test. The test results indicate the presence of a structural break in the country’s FRF. Moreover, the primary balance of Malaysia has an asymmetrical reaction to the country’s public debt and the output gap. This result suggests that a nonlinear behavior of FRF with a structural break is an accurate approach for the fiscal authority in Malaysia (for example, the Ministry of Finance) in designing prudent fiscal policy. This study finds that an asymmetric fiscal reaction in Malaysia neither guarantees fiscal sustainability nor supports output stability, thus suggesting the need for an independent fiscal council to promote prudent fiscal policy.