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

On a Nonlinear Wave Equation of Kirchhoff-Carrier Type: Linear Approximation and Asymptotic Expansion of Solution in a Small Parameter

We consider the Robin-Dirichlet problem for a nonlinear wave equation of Kirchhoff-Carrier type. Using the Faedo-Galerkin method and the linearization method for nonlinear terms, the existence and uniqueness of a weak solution are proved. An asymptotic expansion of high order in a small parameter of a weak solution is also discussed

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

On a Kirchhoff-Carrier equation with nonlinear terms containing a finite number of unknown values

summary:We consider problem (P) of Kirchhoff-Carrier type with nonlinear terms containing a finite number of unknown values $u(\eta _{1},t),\cdots ,u(\eta _{q},t)$ with $0\leq \eta _{1}<\eta _{2}<\cdots <\eta _{q}<1.$ By applying the linearization method together with the Faedo-Galerkin method and the weak compact method, we first prove the existence and uniqueness of a local weak solution of problem (P). Next, we consider a specific case $({\rm P}_{q})$ of (P) in which the nonlinear term contains the sum $S_{q}[u^{2}](t)=q^{-1}\sum _{i=1}^{q}u^{2}(\frac{(i-1)}{q},t)$. Under suitable conditions, we prove that the solution of $({\rm P}_{q})$ converges to the solution of the corresponding problem $({\rm P}_{\infty })$ as $q\rightarrow \infty$ (in a certain sense), here $({\rm P}_{\infty })$ is defined by $({\rm P}_{q})$ in which $S_{q}[u^{2}](t)$ is replaced by $\int _{0}^{1}u^{2}( y,t) {\rm d}y.$ The proof is done by using the compactness lemma of Aubin-Lions and the method of continuity with a priori estimates. We end the paper with remarks related to similar problems

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

On a system of nonlinear wave equations with the Kirchhoff-Carrier and Balakrishnan-Taylor terms

summary:We study a system of nonlinear wave equations of the Kirchhoff-Carrier type containing a variant of the Balakrishnan-Taylor damping in nonlinear terms. By the linearization method together with the Faedo-Galerkin method, we prove the local existence and uniqueness of a weak solution. On the other hand, by constructing a suitable Lyapunov functional, a sufficient condition is also established to obtain the exponential decay of weak solutions