In this work, we designed a micro-hotplate for MEMS gas sensor wafer level packaging. It changes the current package structure. we built a thermal-electromechanical-mechanical simulation model. Based on this model, we...
In this work, we designed a micro-hotplate for MEMS gas sensor wafer level packaging. It changes the current package structure. we built a thermal-electromechanical-mechanical simulation model. Based on this model, we compared Oxide-Nitride-Oxide (ONO) supporting layers and finally chose ONO due to the balanced thermal and mechanical performances. the micro-hotplate was fabricated by MEMS process. After testing, the performance of micro-hotplate samples meets the design requirements. the optimized micro-hotplate with wafer level packaging not only has the advantages of low power consumption, but also realizes the high-density integration of multiple independent temperature-controlled micro hotplates, which is expected to be widely used in the future, especially for Micro-electromechanical systems (MEMS) gas sensor.
Authentication and authorization of a user’s identity are generally done by the service providers or identity providers. However, these centralized systems limit the user’s control of their own identity and are pron...
详细信息
A comparative study of two mixes of data-driven algorithms is proposed in this paper. the discrete-time second-order model-free control known as an intelligent Proportional (iP) controller is tuned considering Virtual...
详细信息
wind and solar energy are the most appealing renewable energy alternatives for producing electrical power. However, due to unpredictable changes in wind speeds, wind resources are uncontrollable. the unpredictable cha...
wind and solar energy are the most appealing renewable energy alternatives for producing electrical power. However, due to unpredictable changes in wind speeds, wind resources are uncontrollable. the unpredictable changes cause technological issues like power harvesting and electrical grid disruptions. As a result, control techniques play an important role in fulfilling the required standards and regulations. the conventional way of realizing the power converter's control structure of wind turbines is through hierarchically organized linear control loops and a pulse width modulator. this structure may be very complex especially when a virtual impedance loop is implemented in case of sharing the power. For the control of power converters, finite control set model predictive control (FCS-MPC) is now a common approach, Because of its adaptability and inherent quickness. this article is looking to discuss using the FCS-MPC solution and considering the current challenges in stand-alone systems. this will enable us to take advantage of its flexibility and fast response. Also, stay away from using linear control loops and instead incorporate the hierarchical control system into a single control unit.
Withthe rapid development of scientific and technological revolution, the Internet of thing systems have been widely deployed in many vertical domains such as smart cities, smart grids, smart agriculture, smart medic...
Withthe rapid development of scientific and technological revolution, the Internet of thing systems have been widely deployed in many vertical domains such as smart cities, smart grids, smart agriculture, smart medical healthcare, etc. In these scenarios, it is an urgent problem to provide a high-effect IoT solution to support high computation ability with strong data security and privacy constraints. In this paper, we propose a novel secure data computing platform based on blockchain crowdsourcing computation. Each data sample is transmitted to its private blockchain for secure data storage. To support a high computation ability, we present a powerful edge network constituted of nearby edge gateways, edge devices, etc. thus, these data on the blockchain can be partitioned and allocated to these edge nodes in a crowdsourcing way. We also deploy different AI tools to meet the requirements of vertical applications. Finally, we evaluate our system performance with a real crowdsourced blockchain computation platform to show our effectiveness in vertical application, e.g., face detection.
A computer simulation systems of power circuits are widely used to calculate transients but thermal calculations are relevant. Usually, they are reduced to calculations using transient thermal resistances without taki...
A computer simulation systems of power circuits are widely used to calculate transients but thermal calculations are relevant. Usually, they are reduced to calculations using transient thermal resistances without taking into account the pulse duration, frequency, which impairs the accuracy of calculations and can lead to an incorrect choice of the power switch or cooling device, leading to overheating. the problem is the approximation of a relative complex characteristics of dynamic thermal impedance given at datasheet without using table values and interpolation. To solve this problem, a two-dimensional exponential function was chosen, which makes it possible to approximate the original curve by four key values. Using an analytical solution, it is possible to make preliminary estimation using symbolic calculation systems. this article presents a algebraic technique for approximating the characteristics of dynamic thermal resistance to calculate the average and maximum junction temperatures. this technique can be used in simulation systems to determine the electromagnetic transient process together withthe temperature.
the concepts of more or fully electric aircraft involve the use of superconducting technologies in conjunction with semiconductor power converters. In this case, the converters can be built into the common cryogenic s...
the concepts of more or fully electric aircraft involve the use of superconducting technologies in conjunction with semiconductor power converters. In this case, the converters can be built into the common cryogenic system. this solution can lead to a significant improvement of the efficiency and power density of electrical system. At the same time, it requires taking into account important design features. this article presents the design of a stabilized power factor correction rectifier with cryogenically-cooled power stage. the results of simulation computer modeling and the design of the converter are demonstrated. the design features of the power stage are considered. the problem of the neutral current is also described. the developed PFC rectifier was assembled and tested. A comparison of the results of simulation computer modeling and the results of experimental studies is given. the results of the experimental studies verify the functionality of the converter, as well as the correctness of simulation computer models.
Vehicle theft has emerged as a notable societal concern within the United States. Despite advancements in detection technology, rates of vehicle theft persist in an upward trend. In response to this exigent issue, an ...
详细信息
ISBN:
(数字)9788993215380
ISBN:
(纸本)9798331517939
Vehicle theft has emerged as a notable societal concern within the United States. Despite advancements in detection technology, rates of vehicle theft persist in an upward trend. In response to this exigent issue, an Internet of things (IoT) system has been devised to confront the challenges encountered by car owners, particularly those whose vehicles lack inherent theft prevention mechanisms. the objective of this research is to introduce a comprehensive system for preventing vehicle theft. the proposed system integrates two fundamental technologies: computer vision for identifying suspicious activity, and vibration and pressure sensors to detect potential physical breaches into the vehicle. Upon detection of suspicious activity, the proposed system quickly dispatches a notification to the user along with a 20-second video capturing the behavior. this IoT system surmounts the constraints of conventional anti-theft systems, thereby enhancing the security of vehicle owners in the United States and curbing the proliferation of vehicle theft.
Extreme weather events, such as hurricanes, severe thunderstorms, and floods can significantly disrupt power grid systems, leading to electrical outages that result in inconvenience, economic losses, and life-threaten...
Extreme weather events, such as hurricanes, severe thunderstorms, and floods can significantly disrupt power grid systems, leading to electrical outages that result in inconvenience, economic losses, and life-threatening situations. there is a growing need for a robust and precise predictive model to forecast power outages, which will help prioritize emergency response before, during, and after extreme weather events. In this paper, we introduce machine-learning models that predict power outage risk at the state level during and after extreme weather events. We jointly utilized two publicly available datasets: the U.S. historical power outage data collected by the Environment for Analysis of Geo-Located Energy Information (EAGLE-$\mathrm{I}^{\mathrm{T}\mathrm{M}}$) system, and the National Weather Service historical weather alert data sets. We highlight our initial result and discuss future work aimed at enhancing the model’s robustness and accuracy for real-world applications.
Aerial systems assembled from multiple modules have the potential to perform tasks that are difficult for traditional aerial vehicles. In this work, we propose a novel aerial system, Carpet, which is composed by a mat...
详细信息
暂无评论