3854 research outputs found
Sort by
Power Systems Infrastructure of Hybrid Electric Fuel Cell Competition Go Kart
No full textThis paper documents the electrical infrastructure design of a Hybrid Go Kart competition vehicle which includes a dual Fuel Cell power system, Ultra Capacitors for energy storage, and a dual AC induction motor capable of independent drive. The Kart was built primarily to compete in the 2009 Formula Zero international event. This paper emphasized the vehicle model and control strategy as a result of three (3) graduate student research projects. The vehicle was fabricated and tested but did not participate in the race competition since the race organization folded. The vehicle model was developed in Simulink to determine whether the fuel cell and ultra-capacitor combination will be sufficient for peak transient power requirement of 14 kW. The vehicle’s functional description and performance specifications are documented including the integration of the fuel cell power modules, energy storage system, power converters, and AC motor and motor controllers
Comparison of SiC MOSFETs and GaN HEMTs Based High-efficiency High-power-density 7.2kW EV Battery Chargers
No full textAs two exemplary candidates of wide-bandgap devices, SiC MOSFETs and GaN HEMTs are regarded as successors of Si devices in medium-to-high-voltage (\u3e1200V) and low-voltage (\u3c;650V) domains, respectively, thanks to their excellent switching performance and thermal capability. With 650V SiC MOSFETs coming into being the direct competition of SiC and GaN in \u3c;650V domains is inevitable, such as Level-2 battery chargers for electric vehicles. This paper applies 650V SiC and GaN to two 240VAC/7.2kW EV battery chargers, respectively, aiming to provide a head-to-head comparison of these two devices in terms of the efficiency, power density, thermal and cost, with the same control strategy of varying the phase-shift and switching frequency to cover the wide input range (80VAC~260VAC) and wide output range (200V~450VDC)
Fostering an Entrepreneurial Mindset in Computer Architecture and Organization Class through a Producer-customer Model
No full textWe recently introduced a producer-customer model to fulfill the Kern Entrepreneurial Engineering Network (KEEN) Students Outcomes, hence help foster an entrepreneurial mindset in students. In this paper, we use our producer-customer model to craft and add innovative lab assignments to the “Computer Architecture and Organization” course. The new lab assignments are based on the six products or IP cores that we have developed. Each product is either defective or improvable. There are some discrepancies between the behavior of a defective product and its user guide; in other words, a defective product does not work as it should. The performance of an improvable product can be enhanced. Each team of students will first work as a customer to identify the defects or the improvable aspects of a product. They will then challenge another team, the producer, to resolve the issues. We have received encouraging anonymous feedback from students
Infusing an Entrepreneurial Mindset into Mechanical Engineering Courses: Two Case Studies
No full textEngineering programs are often criticized for focusing solely on technical education while ignoring industry and business needs. In order to address this situation, entrepreneurial ideas were incorporated directly into existing engineering classes. This paper provides information on the incorporation of entrepreneurial ideas and assignments into two courses offered in the Mechanical Engineering Department. The techniques used to convey the entrepreneurial ideas primarily come from the “Need-Approach-Benefits-Competition” or NABC approach. The successes and failures of the approaches are discussed. Examples are provided to illustrate how these ideas have been used to enhance the undergraduate learning experience
Optimizing Production Schedule with Energy Consumption and Demand Charges in Parallel Machine Setting
Get PDFEnvironmental sustainability concerns, along with the growing need for electricity and associated costs, make energy-cost reduction an inevitable decision-making criterion in production scheduling. In this research, we study the problem of production scheduling on nonidentical parallel machines with machine-dependent processing times and known job release dates to minimize total completion time and energy costs. The energy costs in this study include demand and consumption charges. We present a mixed-integer nonlinear model to formulate the problem. The model is then linearized and its performance is tested through numerical experiments
An ‘(s, S)’ inventory in a queueing system with batch service facility
No full textThis paper considers a single-server queueing model in which the customers are served in batches of varying size depending on predetermined thresholds as well as available inventory. There is a finite buffer for the inventory and the service of every customer requires an inventory item. An (s, S) -type inventory system is used for the models considered in this paper. Initially, the model is studied in detail using the matrix-analytic method by assuming all the underlying random variables to be exponentially distributed. Thereafter, an outline of the model in a more general set up is also presented. Due to complexity of the model when more general assumptions are made on the underlying random variables, simulation is opted after a satisfactory validation with the analytic counterpart of the exponential model. Finally, some illustrative numerical examples are also presented to accomplish our analysis
AutoDrive Section A Faculty and Staff Team Picture September 20th, 2017
No full textThis is an Autodrive team picture taken on Wednesday September 20th, 2017 for A section, containing the faculty and staff.
Pictured from left to right: Craig Hoff (Dean of College of Engineering), Jaerock Kwon (Associate Professor Electrical & Computer Engineering), Diane Peters (Assistant Professor Mechanical Engineering), Yunsheng Wang (Assistant Professor Computer Science), Jungme Park (Assistant Professor Electrical & Computer Engineering), Mehrdad Zadeh (Associate Professor Electrical & Computer Engineering), Xuan Zhou (Assistant Professor Electrical & Computer Engineering), Jennifer Bastiaan (Assistant Professor Mechanical Engineering), Rebecca Reck (Assistant Professor Mechanical Engineering), Giuseppe Turini (Assistant Professor Computer Science), John Geske (Department Head of Computer Science), and Juan Pimentel (Professor Electrical & Computer Engineering).https://digitalcommons.kettering.edu/autodrive_gallery/1007/thumbnail.jp
Numerical and Experimental Study on Multi-pass Laser Bending of AH36 Steel Strips
No full textLaser bending is a process of bending of plates, small sized sheets, strips and tubes, in which a moving or stationary laser beam heats the workpiece to achieve the desired curvature due to thermal stresses. Researchers studied the effects of different process parameters related to the laser source, material and workpiece geometry on laser bending of metal sheets. The studies are focused on large sized sheets. The workpiece geometry parameters like sheet thickness, length and width also affect the bend angle considerably. In this work, the effects of width and thickness on multi-pass laser bending of AH36 steel strips were studied experimentally and numerically. Finite element model using ABAQUS® was developed to investigate the size effect on the prediction of the bend angle. Microhardness and flexure tests showed an increase in the flexural strength as well as microhardness in the scanned zone. The microstructures of the bent strips also supported the physical observations