The effective and efficient quality, security and provenance assurance of microelectronics and electronic products is a persisting challenge for the industry. The impetus towards finding automatic ...solutions that create high confidence about the quality and origin of components assembled on Printed Circuit Boards (PCBs) is high. A novel approach is proposed for microelectronic component detection and classification with high accuracy and confidence. A dedicated multi-source data acquisition, fusion and interpretation, are suggested to reduce uncertainty regarding concurrency, reliability, a vailability, and physical/logical resolution. Increasing the quality of data and subsequently generating the infrastructure for knowledge creation is the main output of this research. A central feature of the proposed solution is the integration and fusion of images from surface and penetrating imaging systems, set specifically to generate the necessary raw data. Experiments reported here demonstrate the merits of the accomplished classification, learning and identification of constituent components through the proposed fusion algorithm 1 , The accuracy of the analytics from the fusion of optical and X-ray algorithms has improved by 5.3 %, compared to optics only. All other sensitivities were also significantly improved; for example, the Chip sensitivity in optical and X-ray images was 89.4% and 85.8%, respectively. With FOXi the metric increased to 94%.
PCB board is an important part of electronic and electrical equipment. In place of piling e-wastes, much of heavy metals in PCB boards percolate into soil, air, river etc. which is a great threaten ...to environment. In order to removal the hazardous materials for WEEE directive, in this paper, a study on enrichment of lead, cadmium ions by multiwalled carbon nanotubes (MWCNTs) as a solid-phase extraction adsorbent was employed. ICP-OES was used to determine the adsorbed concentrations. Some valuable guidelines can be drawn from the following discussions. MWCNTs has proven to be a promising materials for the removal of contaminants owing to its amazing effects of enrichment, the objective content was concentrated about 50-100 fold, and limit of detection (LOD) was 0.5 mugmiddotkg -1 for Pb, 0.2 mugmiddotkg -1 for Cd. The ion exchange or hydrogen binding mechanism can very well explain the heavy metals such as Pb, Cd adsorption onto CNTs. Sorption can be modeled by Freundlich isotherms from which thermodynamic parameters such as free energy change (DeltaG), enthalpy change (DeltaH), and entropy change (DeltaS) can be calculated. DeltaG<0, DeltaS>0 indicated the process to be feasible and spontaneous nature. DeltaH>0 suggested that the process to be an endothermic nature. Enrichment can be influenced by factors as contact time, temperature, pH and initial concentration of adsorbate, etc. Sorption increased with increasing contact time, and temperature, initial concentration of adsorbate. For each of analyte, there is a neutral pH beyond which MWCNTs will be either positively or negatively charged. Desorption studies have shown the applicability to regenerate the CNTs used. The process is economically feasible and easy to carry out. All those add more credits to MWCNTs for removing pollutants from e-wastes, which is meaningful for complying with WEEE directive.
Air-cooled proton exchange membrane fuel cell (PEMFC) is a promising electrochemical device in fields of unmanned aerial and light-duty ground vehicles， with the virtues of simple system, low ...parasitic power and low cost. However, the significantly uneven distribution of internal reaction state of air-cooled PEMFC greatly limits the output performance and stability of the cells. In this study, a PCB test board for the in-situ observation of cell temperature and current density is designed and applied in fuel cells. The result shows that when the average current density is 500 mA/cm2，the difference of temperature and current density reach 20 °C and 400 mA/cm2, respectively. For the optimization of uniformity of reaction state, the effects of hydrogen pulsing interval, hydrogen supply mode, fan configuration and air inlet speed are experimentally explored. Based on the observed results of the PCB test board, optimization proposals of control strategy for air-cooled PEMFC are given: 1) A 30-s pulsing interval of hydrogen is preferred due to its little changes on current density distribution while significant increasement of hydrogen utilization rate. 2) The proposed bidirectional hydrogen flow improves the reaction uniformity, and reduces the fluctuation of current density during hydrogen pulsing discharge; 3) Compared to two paralleled fans, employing a single fan helps to improve the temperature uniformity, with the standard deviation of temperature from 8.9 °C to 6.7 °C; 4) Medium velocity of air inlet speed is preferred due to poor temperature uniformity at low velocity, and low water content at high velocity.
•A PCB test board is designed to obtain the internal reaction state of fuel cell.•The uneven distributed temperature and current density in fuel cell is analyzed.•Optimization proposals of control strategy of air-cooled PEMFC are raised.
This paper investigates optimizing the power exchange between electric vehicles (EVs) and the grid, with a specific focus on the DC-DC converters utilized in vehicle-to-grid (V2G) systems. It ...specifically explores using model predictive control (MPC) in synchronous boost converters to enhance efficiency and performance. Through experiments and simulations, this paper shows that replacing diodes with SIC MOSFETs in boost converters significantly improves efficiency, particularly in synchronous mode, by minimizing the deadtime of SIC MOSFETs during switching. Additionally, this study evaluates MPC’s effectiveness in controlling boost converters, highlighting its advantages over traditional control methods. Real-world validations further validate the robustness and applicability of MPC in V2G systems. This study utilizes TMS320F28379D, one of Texas Instruments’ leading digital signal processors, enabling the implementation of MPC with a high PWM frequency of up to 200 MHz. This processor features dual 32-bit CPUs and a 16-bit ADC, allowing for high-resolution readings from sensors. Leveraging digital signal processing technologies and advanced electronic circuits, this study advances the development of high-performance boost converters, achieving power outputs of up to 48 watts and output voltages of 24 volts. Electronic circuits (PCB boards) have been devised, implemented, and evaluated to showcase their significance in advancing efficient V2G integration.
To solve the signal integrity problem which exists in ARM9 core PCB board design is the foundation to ensure high-speed ARM9 embedded system’s security and reliability. This paper make research on ...reflection, crosstalk and timing issues which exist in the design process of the ARM9 embedded system core PCB board, and perform simulation with the help of Cadence simulation and analysis software and IBIS model. The results show that match impedance is the key to solve the reflection problem,appropriate length and line spacing is help to solve the crosstalk problem,make the clock lines and data lines isometric can effectively reduce the timing issues.
In order to develop an anti-broadband electromagnetic interference wired phone, speech enhancement, electromagnetic shielding, PCB board electromagnetic compatibility and filtering are the usual ...measures. Realization of speech enhancement can resolve practical problems of SLT dialing error in strong electromagnetic interference, voice unclear and intermittent communication. The experiment shows that in 50m radiating field of high-power VHF radar or shortwave radio, speech intelligibility of phone designed was higher than that of general phone and had no whistling or ringing.
This paper introduces the importance of avionics printed circuit board(PCB), and states the principle of avionics PCB routing. The principle of cross-talk generation between PCB board lines is ...analyzed, and the 3D electromagnetic simulation software CST is used for modeling and simulation of the protection belt, which verifies the effectiveness of the protection belt on cross-talk suppression, and analyzes the influence of the spacing of GND VIA on the cross-talk of transmission lines. This paper provides a reference for PCB protection belt design of airborne electronic equipment.
