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Three dimensional (3D) stacking of semiconductor chips has the advantages of high electrical performance, including improved bandwidth, reduced wire interconnection lengths, low cost, and heterogeneous integration. However, the power density increases sharply within the stack and the thermal management challenges become major bottlenecks. Inter-tier microfluidic cooling with microgaps with surface...
We investigated two phase heat transfer in staggered and inline micro pin fin arrays, using deionized water and HFE-7200 as working fluids with exit qualities up to 90%,. The inline and staggered arrays have equivalent pin fin width of 153µm and height of 305µm on a heated base area of 0.96cm width by 2.88cm length. Mass fluxes ranged from 200 kg/m2s to 600 kg/m2s for HFE-7200 and 400 kg/m2s to 1300...
Recent technological advances in atom probe tomography (APT) have led to unprecedented data acquisition capabilities that routinely generate data sets containing hundreds of millions of atoms. Detecting nanoscale clusters of different atom types present in these enormous amounts of data and analyzing their spatial correlations with one another are fundamental to understanding the structural properties...
In this paper, a beamforming and cell searching method is proposed for a mobile station (MS) with antenna array to compensate the high attenuation in a millimeter wave (mm-wave) OFDM-based cellular systems. A cell searching and direction-of-arrival (DoA) estimation method is proposed for a multipath environment, even with the existence of the symbol timing offsets (STOs) and carrier frequency offsets...
To improve the performances of a communication link, both in terms of capacity and bit error rate, MIMO technique is a solution which has been widely studied. However, in road or railway tunnels, the waves are guided by the structure and the angular spread of the rays, both at the transmitting side and at the receiving side, is rather small. Nevertheless, improvement of the capacity based on the Shannon...
We propose a comprehensive and computationally efficient methodology for the estimation of correlated memory fail probabilities. The methodology allows, for the first time, to accurately predict the number of failing memory parts in the presence of correlation between the memory fails due to shared peripheral logic. It relies on importance sampling to model the fail region and emulate different memory...
The proliferation of mobile ubiquitous devices faces a hurdle in the form of high resource consumption rates that restrict longevity. Several low-power devices and application designs and optimization techniques have been proposed. Simultaneously, energy harvesting technologies are increasingly being viewed as a complementary technique to drive down resource consumption rates and even achieve self-sustenance...
This paper describes the design and implementation of an array system that includes a frequency domain beamformer that will coherently combine the downlinked signals from up to eight inputs at each of NASA's three Deep Space Communications Complexes (DSCC). The array signal processor digitizes inputs with an intermediate frequency (IF) bandwidth of 100 to 600 MHz, coherently combines the inputs digitally,...
This paper presents analysis and comparison of weighted subspace based MUSIC for the direction of arrival (DOA) using spatially smoothed forward (FS) only estimates, forward-backward smoothed (FBS) estimates of array correlation matrix. It is shown that for subspace technique like MUSIC, the FBS estimate techniques performs better as compared to FS estimates especially for correlated signals in multipath...
By incorporating two-dimensional photonic crystals into the surface of InGaN-based LEDs, the strong correlation between the air duty cycle and the light extraction efficiency of LEDs was demonstrated by optical and electrical measurement results.
Two photons in an entangled, spatially correlated (anti-correlated) state transmitted through an Anderson disordered lattice maintain their correlation (anti-correlation) but exhibit coincidence-map speckle in the Fourier plane.
We show that coherent light traveling through a 1-D lattice of coupled waveguides with off-diagonal disorder exhibits super-thermal statistics (g(2) > 2) with a photonic thermalization gap at asymptotic propagation distances.
Mosaicked color filter arrays and demosaicking methods for multispectral images have been proposed in recent years. Several studies have evaluated the multispectral filter array (MSFA) pattern, but a method to optimize the pattern has not been proposed. We focus on the spatial arrangement of MSFAs to improve the demosaicked image quality. To evaluate the filter arrangement, we propose a new metric...
A novel sensing technique called diffused sensing which exploits homogeneous and isotropically reflected waves is applied for estimating wave intensity. By analyzing the observed signals with a sensor array, the intensity of the wave arriving from each source is estimated. However, it is difficult to estimate the wave intensity from a mixture of waves of various wavelengths. With diffused sensing,...
In this paper, we present a duality between two problems: the reconstruction of the angular periodogram from spatial-domain signals received at different time indices and that of the frequency periodogram from time-domain signals received at different wireless sensors. We assume the existence of a multiband structure in either the angular or frequency domain representation of the received spatial...
In most research of PN code acquisition performance of antenna array, the signal DOA is regarded as a constant. But in practice, the signal DOA always spreads to a certain extent, which affects PN code acquisition performance. In this paper, the angle extension is introduced into the direct-sequence spread-spectrum array signal model, and PN code acquisition performance is analyzed through CFAR algorithm...
To allow measurement of the equilibrium density fluctuations on a nanometer-length scale using small angle X-ray scattering, an asynchronous event-driven-address time-stamped (EDATS) pixelated array detector, operational over correlation time spans ranging from less than 10-6 to greater than 104 seconds, was designed, fabricated, and tested. Its performance was validated for use in X-ray photon correlation...
In this paper, we show that the generalization by D.S.Kim in 2010 for the construction of sequence family of period q−1 using the Sidelnikov sequences of period qd−1 can be further generalized by removing the condition that gcd(q − 1, d) = 1. It turned out that the correlation bound remains the same and the size of the family is almost the same as the one with the previous condition.
In this paper, a novel DOA estimation method without angles pre-estimating for Wideband Signals is proposed. The main idea is to design a novel Direction-Free focusing matrix using the decomposed representation of the array manifold matrix, where the angle parameter is separated from the array geometry and the frequency parameter. The focusing matrix is derived using a method similar to RSS. The novel...
In this paper a method for the accurate and fast determination of direction of arrival (DOA) of impinging electromagnetic signal radiated from stochastic sources in the far-field is proposed. The method is based on neural models using MLP (Multi-Layer Perceptron) artificial neural network. To illustrate the applicability of the proposed method, two MLP models for one-dimensional (1D) DOA estimation...
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