INNOVATIVE INTEGRATION BASED ON SILICON-CORE TECHNOLOGIES FOR SENSOR AND COMMUNICATIONS APPLICATIONS

2000 ◽  
Vol 10 (01) ◽  
pp. 205-215 ◽  
Author(s):  
TADAO NAGATSUMA ◽  
KATSUYUKI MACHIDA ◽  
HIROMU ISHII ◽  
NABIL SAHRI ◽  
MITSURU SHINAGAWA ◽  
...  

This paper describes an innovative system integration scheme wherein heterogeneous materials and devices, including photonic devices as well as electronics, are organically integrated on silicon-core circuitry to achieve better performance, higher functionality and lower cost. First, some general integration technology trends in semiconductor electronics are described. Then, after a discussion of new heterogeneous integration schemes based on silicon-core technologies, recent attempts and applications are shown such as low power LSIs, sensors and micromachine switches on silicon and milimeter-wave photonics.

Water ◽  
2021 ◽  
Vol 13 (6) ◽  
pp. 785
Author(s):  
Arman Rokhzadi ◽  
Musandji Fuamba

This paper studies the air pressurization problem caused by a partially pressurized transient flow in a reservoir-pipe system. The purpose of this study is to analyze the performance of the rigid column model in predicting the attenuation of the air pressure distribution. In this regard, an analytic formula for the amplitude and frequency will be derived, in which the influential parameters, particularly, the driving pressure and the air and water lengths, on the damping can be seen. The direct effect of the driving pressure and inverse effect of the product of the air and water lengths on the damping will be numerically examined. In addition, these numerical observations will be examined by solving different test cases and by comparing to available experimental data to show that the rigid column model is able to predict the damping. However, due to simplified assumptions associated with the rigid column model, the energy dissipation, as well as the damping, is underestimated. In this regard, using the backward Euler implicit time integration scheme, instead of the classical fourth order explicit Runge–Kutta scheme, will be proposed so that the numerical dissipation of the backward Euler implicit scheme represents the physical dissipation. In addition, a formula will be derived to calculate the appropriate time step size, by which the dissipation of the heat transfer can be compensated.


2015 ◽  
Vol 143 (9) ◽  
pp. 3838-3855 ◽  
Author(s):  
Steven Sandbach ◽  
John Thuburn ◽  
Danail Vassilev ◽  
Michael G. Duda

Abstract An important question for atmospheric modeling is the viability of semi-implicit time integration schemes on massively parallel computing architectures. Semi-implicit schemes can provide increased stability and accuracy. However, they require the solution of an elliptic problem at each time step, creating concerns about their parallel efficiency and scalability. Here, a semi-implicit (SI) version of the Model for Prediction Across Scales (MPAS) is developed and compared with the original model version, which uses a split Runge–Kutta (SRK3) time integration scheme. The SI scheme is based on a quasi-Newton iteration toward a Crank–Nicolson scheme. Each Newton iteration requires the solution of a Helmholtz problem; here, the Helmholtz problem is derived, and its solution using a geometric multigrid method is described. On two standard test cases, a midlatitude baroclinic wave and a small-planet nonhydrostatic gravity wave, the SI and SRK3 versions produce almost identical results. On the baroclinic wave test, the SI version can use somewhat larger time steps (about 60%) than the SRK3 version before losing stability. The SI version costs 10%–20% more per step than the SRK3 version, and the weak and strong scalability characteristics of the two versions are very similar for the processor configurations the authors have been able to test (up to 1920 processors). Because of the spatial discretization of the pressure gradient in the lowest model layer, the SI version becomes unstable in the presence of realistic orography. Some further work will be needed to demonstrate the viability of the SI scheme in this case.


2017 ◽  
Vol 2017 (S1) ◽  
pp. 1-40
Author(s):  
Subramanian S. Iyer (Subu)

Silicon features have scaled by over 1500X for over six decades, and with the adoption of innovative materials delivered better power-performance, density and till recently, cost per function, almost every generation. This has spawned a vibrant system-on-chip (SoC) approach, where progressively more function has been integrated on a single die. The integration of multiple dies on packages and boards has, however, scaled only modestly by a factor of three to five times. However, as SoCs have become bigger and more complex, the Non-Recurring Engineering (NRE) Charge and time to market have both ballooned out of control leading to ever increasing market consolidation. We need to address this problem through novel methods of system Integration. With the well-documented slowing down of scaling and the advent of the Internet of Things, there is a focus on heterogeneous integration and system-level scaling. Packaging itself is undergoing a transformation that focuses on overall system performance through integration rather than on packaging individual components. We propose ways in which this transformation can evolve to provide a significant value at the system level while providing a significantly lower barrier to entry compared with a chip-based SoC approach that is currently used. More importantly it will allow us to re-architect systems in a very significant way. This transformation is already under way with 3-D stacking of dies, Wafer level fan-out processing, and will evolve to make heterogeneous integration the backbone of a new SoC methodology, extending to integrate entire Systems on Wafers (SoWs). We will describe the technology we use and the results to-date. This has implications in redefining the memory hierarchy in conventional systems and in neuromorphic systems. We extend these concepts to flexible and biocompatible electronics.


Author(s):  
Alexander Humer ◽  
Johannes Gerstmayr

Many conventional time integration schemes frequently adopted in flexible multibody dynamics fail to retain the fundamental conservation laws of energy and momentum of the continuous time domain. Lack of conservation, however, in particular of angular momentum, may give rise to unexpected, unphysical results. To avoid such problems, a scheme for the consistent integration of modally reduced multibody systems subjected to holonomic constraints is developed in the present paper. As opposed to the conventional approach, in which the floating frame of reference formulation is combined with component mode synthesis for approximating the flexible deformation, an alternative, recently proposed formulation based on absolute coordinates is adopted in the analysis. Owing to the linear relationship between the generalized coordinates and the absolute displacement, the inertia terms in the equations of motion attain a very simple structure. The mass matrix remains independent of the current state of deformation and the velocity dependent term known from the floating frame approach vanishes due to the absence of relative coordinates. These advantageous properties facilitate the construction of an energy and momentum consistent integration scheme. By the mid-point rule, algorithmic conservation of both linear and angular momentum is achieved. In order to consistently integrate the total energy of the system, the discrete derivative needs to be adopted when evaluating the strain energy gradient and the derivative of the algebraic constraint equations.


2006 ◽  
Vol 134 (10) ◽  
pp. 3006-3014 ◽  
Author(s):  
James A. Hansen ◽  
Cecile Penland

Abstract The delicate (and computationally expensive) nature of stochastic numerical modeling naturally leads one to look for efficient and/or convenient methods for integrating stochastic differential equations. Concomitantly, one may wish to sensibly add stochastic terms to an existing deterministic model without having to rewrite that model. In this note, two possibilities in the context of the fourth-order Runge–Kutta (RK4) integration scheme are examined. The first approach entails a hybrid of deterministic and stochastic integration schemes. In these examples, the hybrid RK4 generates time series with the correct climatological probability distributions. However, it is doubtful that the resulting time series are approximate solutions to the stochastic equations at every time step. The second approach uses the standard RK4 integration method modified by appropriately scaling stochastic terms. This is shown to be a special case of the general stochastic Runge–Kutta schemes considered by Ruemelin and has global convergence of order one. Thus, it gives excellent results for cases in which real noise with small but finite correlation time is approximated as white. This restriction on the type of problems to which the stochastic RK4 can be applied is strongly compensated by its computational efficiency.


1995 ◽  
Vol 23 (3) ◽  
pp. 113-129 ◽  
Author(s):  
Mamit Deme

There is a scarcity of published statistical analysis that examines the impact of economic integration schemes in Africa. This study fills the gap in the literature. The impact of Economic Community of West African States (ECOWAS) on trade flows of its member countries is examined applying an econometric analysis. The parameters of a multivariate trade-flows model are estimated using a panel data of the 1975 to 1991 period. The results suggest that the regional integration scheme has succeeded in increasing trade flows between member countries. The general view in the literature is that African integration schemes have failed to increase trade flows.


2020 ◽  
Vol 98 (6) ◽  
pp. 93-106
Author(s):  
Christopher D Nordquist ◽  
Erik Skogen ◽  
Seth Fortuna ◽  
Andrew E Hollowell ◽  
Caroline Hemmady ◽  
...  

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