The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
Co-prime arrays and samplers are popular sub-Nyquist schemes for estimating second order statistics at the Nyquist rate. This paper focuses on the perturbations in the array locations or sampling times, and analyzes its effect on the difference set. Based on this analysis we propose a method to estimate the autocorrelation which makes best use of the sampled data in order to improve the estimation...
Resistive crossbar arrays show significant improvement in terms of energy and area efficiency when compared to current SRAM based memory technologies. However, due to its resistive nature, it suffers from undesired current sneak-paths complicating read-out procedures. In this paper, we present a voltage-based reading technique in resistive memories. The simplicity of the readout circuit enables parallel...
A 4 kb fully differential 8-port SRAM bitcell array (6 read ports and 2 write ports) is presented in this paper. This 8-port SRAM provides simultaneous access, high system throughput and a great read static noise margin by isolating the read ports from storage nodes. At 0.4 V supply voltage, designed 8-port SRAM bitcell shows 123, 137 and 123 mV static noise margin during read, write and standby modes,...
Gradient errors in device arrays cause mismatch between device parameters, which in turn degrade linearity performance of data converters realized with these arrays. A practical “outputs averaging” technique for string DACs is presented to release complex routing problems in gradient reduction patterns. An N-bit string is divided into multiple substrings and the substrings' outputs are averaged to...
Computing machine learning models in the cloud remains a central problem in big data analytics. In this work, we introduce a cloud analytic system exploiting a parallel array DBMS based on a classical shared-nothing architecture. Our approach combines in-DBMS data summarization with mathematical processing in an external program. We study how to summarize a data set in parallel assuming a large number...
Graph algorithms such as breadth-first search (BFS) have been gaining ever-increasing importance in the era of Big Data. However, the memory bandwidth remains the key performance bottleneck for graph processing. To address this problem, we utilize processing-in-memory (PIM), combined with non-volatile metal-oxide resistive random access memory (ReRAM), to improve the performance of both computation...
The performance of superdirective beamforming of a practical circular hydrophone array is investigated. The received signal of a 16-element circular hydrophone array with radius of 0.25m are measured in the anechoic water tank. The array manifold at the frequency of 1.11kHz is obtained. The superdirective beamforming of the circular array is designed and realized. The correctness and effectiveness...
In this paper, we describe the development of a new L-band (1.4 GHz) Cryogenic Phased Array Feed (PAF) system, referred to as the GBT2 array. Results from initial measurements made with the GBT2 array are also presented. The PAF was developed for the Green Bank Telescope (GBT) as part of the Focal L-band Array for the GBT (FLAG) project. During the first stage of the development work (Phase I), a...
The objective of the work is to provide a recommender system through optimization. The users place orders to suppliers through email, requesting preferences based on cost and delivery date. Optimization algorithms are formulated to provide an optimal mix of the products to the users based on the cost and speed of delivery. The algorithm takes the availability and cost of the products with the suppliers...
Inverter is an integral part of any renewable energy conversion system. For a multilevel inverter, attempt is to obtain an output voltage which is near sinusoidal in shape. The switching angles and the voltage levels are decided in such a way so as to maximize the fundamental component with minimum THD. In this paper, it is shown how a simple method like Grey Analysis method can be used to decide...
In this paper the hardware designed for the SKA Low (Square Kilometre Array) correlator and beamformer (CBF) is discussed. SKA-Low is a low frequency aperture array (LFAA) to be located in remote Western Australia. The array is collecting radio signals in the frequency range from 50 to 350 MHz. The large number of dual polarization antennas (131072) are distributed over a total of 512 stations with...
In this paper, we present a greedy sensor selection algorithm for minimum variance distortionless response (MVDR) beamforming under a modular budget constraint. In particular, we propose a submodular set-function that can be maximized using a linear-time greedy heuristic that is near optimal. Different from the convex formulation that is typically used to solve the sensor selection problem, the method...
ASKAP has recently started its Early Science program with 12 MkII PAF-equipped antennas and 36 beams simultaneously covering a 30 square degree field of view. The first observations have focused on mapping extragalactic neutral hydrogen in galaxy groups and clusters selected by the ‘WALLABY’ Survey Science Team. Significant efforts from engineers, software designers, and scientists are overcoming...
This paper proposes the most efficient I/O-based out-of-core stencil algorithm for large-capacity type of non-volatile memory (NVM), such as flash. The paper evaluates the performances of various out-of-core stencil algorithms and implementations designed for flash. The algorithms for flash are very different from existing algorithms designed for memory-and-cache, host-and-GPU, and local-and-remote...
String objects, the most commonly used objects in Java programs, are immutable (read-only) and easily identified. Previous analysis of sharing string objects in the Java Virtual Machine showed promising results, however it is clear that sharing a wider set of objects would result in better performance. Automatic object selection for sharing is non-trivial, because in the current state, only read-only...
We experimentally demonstrate visible-light co ding/de co ding utilizing hexadecimal vector beam array for parallel communication link. The hexadecimal base mode is investigated and 128-ary is also available. We present vector beam array carrying 4×6/6×8/12×16 hexadecimal numbers and error-free data stream transmission performance is also demonstrated.
When a device on network communicates with copious other devices during a time window, this device is called a super point. Super points play important roles in network because they are usually servers, hosts running P2P applications, worms, DDos victims. Super points may change with the time. How to locating these super points from core network efficiently is a hard task. This paper proposed an algorithm...
In this paper, a systematic approach to finding an optimized switching sequence for a current steering DAC to reduce the static non-linearity is presented. A methodology for calculating the error patterns of a particular process is explained. Also, a novel algorithm is proposed to find an INL bounded optimized switching sequence for any gradient profile which can even compensate for the linear gradient...
With the development of cyber threats on the Internet, the number of malware, especially unknown malware, is also dramatically increasing. Since all of malware cannot be analyzed by analysts, it is very important to find out new malware that should be analyzed by them. In order to cope with this issue, the existing approaches focused on malware classification using static or dynamic analysis results...
Parity declustering is widely deployed in erasure coded storage systems so as to provide fast recovery and high data availability. However, to perform scaling on such RAIDs, it is necessary to preserve the parity declustered data layout so as to guarantee the RAID performance after scaling. Unfortunately, existing scaling algorithms fail to achieve this goal so they can not be applied for scaling...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.