Walsh spectral techniques for logic synthesis FPGA

The implementation value of multi-output Boolean functions in logic synthesis FPGA can be reduced by using Walsh spectral representation. This paper proposes an algorithm for calculating the maximum coefficient of the autocorrelation function of BF without generating a truth table, using the heuristic procedure limits the maximum autocorrelation coefficients of sorting on a small subset of the function. We also suggest a spectral technique of the linear function transformation defined by disjoint cubes. This method for decomposition of BF, which allows to reducing the complexity of the linear part of the corresponding blocks about 25-55%, and the complexity of the nonlinear part of the blocks do not increase more than 10%, compared to the traditional approach

Minimize Logic Synthesis FPGA – Extraction And Substitution Problems

The objective of multi-level logic synthesis of FPGA is to find the “best” multi-level structure, where “best” in this case means an equivalent presentation that is optimal with respect to various parameters such as size, speed or power consumption... Five basic operations are used in order to reach this goal: decomposition, extraction, factoring, substitution and collapsing. In this paper we propose a novel application of Walsh spectral transformation to the evaluation of Boolean function correlation. In particular, we present an algorithm with approach to solve the problems of extraction and substitution based on the use of Walsh spectral presentation. The method, operating in the transform domain, has appeared to be more advantageous than traditional approaches, using operations in the Boolean domain, concerning both memory occupation and execution time on some classes of functions

Red-emitting Ba2Si5N8Eu2+ conversion phosphor: A new selection for enhancing the optical performance of the in-cup packaging MCW-LEDs

In this research, the influence of the red-emitting Ba2Si5N8Eu2+ convention phosphor on the optical performance of the 7,000K and 7,700K in-cup packaging multi-chip white LEDs (MCW-LEDs) is investigated. The effect of the red-emitting Ba2Si5N8Eu2+ convention phosphor is demonstrated based on Mie Theory by Mat Lab and Light Tools software. The research results indicated that the optical performance of MCW-LEDs was crucially affected by the red-emitting Ba2Si5N8Eu2+ phosphor's concentration. This paper provides an essential recommendation for selecting and developing the phosphor materials for MW-LEDs manufacturing.Web of Science51art. no. 148615

Effect of the green-emitting CaF2:Ce3+,Tb3+ phosphor particles’ size on color rendering index and color quality scale of the in-cup packaging multichip white LEDs

In this paper, we investigate the effect of the green-emitting CaF2:Ce (3+), Tb (3+) phosphor particle's size on the color rendering index (CRI) and the color quality scale (CQS) of the in-cup packaging multichip white LEDs (MCW-LEDs). For this purpose, 7000K and 8500K in-cup packaging MCW-LEDs is simulated by the commercial software Light Tools. Moreover, scattering process in the phosphor layers is investigated by using Mie Theory with Mat Lab software. Finally, the research results show that the green-emitting CaF2: Ce (3+), Tb (3+) phosphor's size crucially influences on the CRI and CQS. From that point of view, CaF2: Ce (3+), Tb (3+) can be proposed as a potential practical direction for manufacturing the in-cup packaging phosphor WLEDs.Web of Science13235134

Enhancing lighting performance of white LED lamps by green emitting Ce,Tb phosphor

With the development of high-efficiency and high-power Light-Emitting Diodes (LEDs), it has become possible to use LEDs in lighting and illumination. In last decades, developing a new method for improving lumen output and Angular Color Uniformity (ACU) is the main direction in LED technology. In this paper, an innovative approach for enhancing lighting performance (lumen output and angular color uniformity) of Multi-Chip White LED lamps (MCW-LEDs) was proposed and demonstrated by mixing the green Ce0.67Tb0.33MgAl11O19: Ce,Tb (CeTb) phosphor into their phosphor compounding. With varying CeTb concentration, ACU and lumen output with Conformal Phosphor Package (CPP) and In-cup Phosphor Package (IPP) are calculated, displayed and analyzed. The results show that the lumen output and the ACU of 7000 K and 8500 K MCW-LEDs increased remarkably in comparison with the older works. Using green CeTb is a prospective method for improving lighting performance of MCW-LEDs in future

Soft Robotic Link with Controllable Transparency for Vision-based Tactile and Proximity Sensing

Robots have been brought to work close to humans in many scenarios. For coexistence and collaboration, robots should be safe and pleasant for humans to interact with. To this end, the robots could be both physically soft with multimodal sensing/perception, so that the robots could have better awareness of the surrounding environment, as well as to respond properly to humans' action/intention. This paper introduces a novel soft robotic link, named ProTac, that possesses multiple sensing modes: tactile and proximity sensing, based on computer vision and a functional material. These modalities come from a layered structure of a soft transparent silicon skin, a polymer dispersed liquid crystal (PDLC) film, and reflective markers. Here, the PDLC film can switch actively between the opaque and the transparent state, from which the tactile sensing and proximity sensing can be obtained by using cameras solely built inside the ProTac link. In this paper, inference algorithms for tactile proximity perception are introduced. Evaluation results of two sensing modalities demonstrated that, with a simple activation strategy, ProTac link could effectively perceive useful information from both approaching and in-contact obstacles. The proposed sensing device is expected to bring in ultimate solutions for design of robots with softness, whole-body and multimodal sensing, and safety control strategies.Comment: Submitted to RoboSoft 2023 for review. Final content subjected to chang

Influence of scattering enhancement particles CaCO3, CaF2, SiO2 and TiO2 on color uniformity of white LEDs

In this paper, the influence of scattering enhancement particles CaCO3, CaF2, SiO2 and TiO2, adding to YAG:Ce phosphor compounding, on color uniformity of white LEDs (W-LEDs) was presented. Firstly, the physical model of multi-chip W-LEDs is simulated and demonstrated by using commercial LightTools 8.1.0 program. After that, the influence of scattering enhancement particles on color uniformity is calculated and analyzed. With using the Monte Carlo simulation and the Mie-scattering theory, the color uniformity improvement of an 8500~K W-LEDs is demonstrated convincingly. From the researched results, the best color uniformity can be accomplished with TiO2 articles. The results and discussions provided a practical approach for higher-quality manufacturing W-LEDs

Enhancement of color rendering index for white light LED lamps by red Y2O3:EU3+ phosphor

We present an application of the red Y2O3:Eu3+ dopant phosphor compound for reaching the color rendering index as high as 86. The Multi-Chip White LED lamps (MCW-LEDs) with high Correlated Color Temperatures (CCTs) including 7000 K and 8500 K are employed in this study. Besides, the impacts of the Y2O3:Eu3+ phosphor on the attenuation of light through phosphor layers of the various packages is also demonstrated based on the Beer-Lambert law. Simulation results provide important conclusion for selecting and developing the phosphor materials in MCW-LEDs manufacturing

Co-doping green-emitting CaF2:Ce3+,Tb3+ and yellow-emitting phosphor particles for improving the cct deviation and luminous efficacy of the in-cup phosphor packaging WLEDs

In last few decades, Light emitting diodes (LEDs) with a series of excellence advantages is considered as the next generational light source. In this research, by co-doping the Green-emitting CaF2:Ce3+,Tb3+ phosphor to yellow-emitting YAG: Ce phosphor compound of the 7000K and 8500 K in-cup packaging white LED lamps (WLEDs), an innovative solution for improving color uniformity and luminous efficiency is proposed, investigated, and demonstrated. By using Mie Theory with Mat Lab and Light Tool software, the obtained results show that the CCT Deviation and luminous efficacy of the 7000 K and 8500 K in-cup phosphor packaging WLEDs crucial are influenced by the Green-emitting CaF2:Ce3+,Tb3+ phosphor's concentration. The results show that the green-emitting phosphor can beconsider as a potential practical solution for manufacturing the in-cup packaging phosphor WLEDs in the near future.Web of Science12389889

Sr2Si5N8:Eu2+ phosphor: a novel recommendation for improving the lighting performance of the 7000 K remote-packaging white LEDs

In the last few years, white LED lamps (WLEDs) have been popularly used in general lighting because of some excellent properties, such as fast response time, environment friendliness, small size, long lifetime, and high efficiency. In this research, we propose a novel recommendation for improving the lighting performance (in terms of the colour rending index, colour quality scale, and luminous efficiency) of the 7000 K remote-packaging WLEDs by adding the red-emitting Sr2Si5N8:Eu2+ phosphor to the yellow-emitting YAG:Ce phosphor compound. In the first stage, we use MATLAB to investigate the light scattering process based on Mie Theory. After that, we use the Light Tool software to simulate and demonstrate this process. Finally, the simulation results are verified with analytical analysis, which clearly shows that the lighting performance of the 7000 K remote-packaging WLEDs significantly depended on the Sr2Si5N8:Eu2+ concentration. The results provided a potential practical solution for manufacturing remote phosphor WLEDs in the near future.Web of Science67434133