This book introduces a Gate Diffusion Input (GDI) methodology as an alternative approach in digital circuits. In this technique, a wide range of complex logic functions can be realized by using a lower number of CMOS transistors. The advantages of using GDI technique are multi-folded. The first is to implement digital gates (i.e. inverters, NAND, NOR, XOR, XNOR, buffers, etc.) with very low propagation delay and high logic level swing. As a second advantage, the GDI-based circuits consume lower power consumption and chip area compared with the CMOS equivalent. This provides a new implementation of digital circuits which are suitable for longer-lasting portable devices, like smartphones, tablets, IoT, etc.. A third advantage is the simplicity of circuit design by using very small cell library. In this book, after a brief review of GDI specifications, we will discuss different architectures of GDI-based digital circuits that have been recently proposed.
The Rac1 GTPase plays key roles in cytoskeletal organization, cell motility and a variety of physiological and disease-linked responses. Wild type Rac1 signaling entails dissociation of the GTPase from cytosolic Rac1-Rho GDP dissociation inhibitor (GDI) complexes, translocation to membranes, activation by exchange factors, effector binding, and activation of downstream signaling cascades. Out of those steps, membrane translocation is the less understood. Using transfections of a expression cDNA library in cells expressing a Rac1 bioreporter, we previously identified a cytoskeletal feedback loop nucleated by the F-actin binding protein coronin 1A (Coro1A) that promotes Rac1 translocation to the plasma membrane by facilitating the Pak-dependent dissociation of Rac1-Rho GDI complexes. This screening identified other potential regulators of this process, including WDR26, basigin, and TMEM8A. Here, we show that WDR26 promotes Rac1 translocation following a Coro1A-like and Coro1A-dependent mechanism. By contrast, basigin and TMEM8A stabilize Rac1 at the plasma membrane by inhibiting the internalization of caveolin-rich membrane subdomains.
MGDI technique, in which a low number of transistors are used to reduce the power consumption and area on chip of digital circuits. In this paper the full adder is introduced using MGDI technique. 2 bit comparator, full subtractor were introduced using GDI technique. Then these digital circuits were compared with traditional CMOS transistors in terms of power dissipation, number of transistors, area, speed and delay.
In this thesis work, a new technique for designing logic circuits called the Modified Gate Diffusion Input (MGDI) logic is discussed. This logic is adopted from the Gate Diffusion Input (GDI) technique. GDI was first proposed in the year 2002 for solving the problems associated with different CMOS logic styles. GDI cell can be used to implement wide variety of complex logic functions using only two transistors. GDI technique allows design of high speed and low power circuits with reduced number of transistors as compared to static CMOS and Pass Transistor Logic (PTL) techniques. This work aims to design a various high performance adders and multipliers.
The development and introduction of new engine technologies are primarily motivated by the need to comply with increasingly stringent emissions legislation and to reduce fuel consumption. One of the most important of these new engine technologies is Gasoline Direct Injection (GDI), which is considered to be an important and cost-effective measure to meet both targets. Computational Fluid Dynamics (CFD) simulations and optical methods are important tools in the development of direct injection gasoline engines. The aim of this work was to develop models, methods, and a numerical platform for simulating the behavior of GDI engines using a variety of fuels, including gasoline-ethanol blends. One of the most important goals of this work was to devise improvements to OpenFOAM (a free, open source CFD package) that would increase its utility as a tool for studying GDI engines, as there is strong industrial demand for inexpensive software. This book addressed two important problems relevant to modelling combustion in a GDI engine, including combustion chemistry and spray modelling.
As technology scales into the nanometer regime leakage current, active power, delay and area are the important metric for the analysis and design of complex arithmetic logic circuits. In this paper, low leakage 1bit full adder cell are proposed for mobile applications and a novel technique has been introduced with improved staggered phase damping technique and also Gated Diffusion Input (GDI) technique for further reduction in the Active power. Leakage power is being estimated when the circuits are connected with a sleep transistor, Further compared to the Base case and Design1 and Design2 and GDI Technique when a circuit is connected to sleep transistor. We introduced a new transistor resizing approach for 1bit full adder cells to determine the optimal sleep transistor size which reduce the leakage power and Area. The simulation results depicts that the proposed design also leads to efficient 1bit full adder cells in terms of standby leakage power, active power. We have performed simulations using Microwind 90nm standard CMOS technology at room temperature with supply voltage of 1V.
Understanding highly complex nature of flow in an IC engine is essential to optimize its performance. However, the events like reciprocating motion of piston, motion of valves, turbulence generation, spray and mixing lead to a complex flow pattern. CFD is very useful in computing and understanding this complex flow pattern. In this book, all aspects of CFD technique to simulate the mixing of fuel with air in GDI engines are explained. The book covers the governing equations, numerical techniques for solving them, method of analysis of data (in the context of mixing processes) and programming techniques. The book will be useful for professionals who are performing CFD analysis using CFD softwares for thermal systems specifically reciprocating systems like engines, compressors and systems involving sprays, mixing etc. It is also useful for those who are developing CFD tools.
The flow behavior of liquid fuel through injectors greatly affects its atomization and combustion efficiency inside an engine. A computational fluid dynamics (CFD) model is developed using the open source CFD library OpenFOAM to predict the fuel flow in injectors that are used in the gasoline direct injection systems (GDI). Additionally, a method is formulated to couple this model with fluids that represent the physical properties of gasoline-ethanol blends like E85.