Blind Separation of Coherent Signals Based on Toeplitz Matrix Reconstruction

A new blind beamforming algorithm for separating and estimating coherent signals arriving at an antenna array is proposed in this paper. This algorithm is implemented through arranging the received data’s correlation function of each array element and reference array element (the first array element), to form the Hermitian Toeplitz matrix first. Then through the singular value decomposition of the matrix the signal subspace and noise subspace can be get, in order to achieve the direction vector of coherent sources to beamform, which can separate the independent signals from different directions effectively without knowing the transcendent knowledge of the signals. The new approach can estimate the coherent signals’ direction-of-arrival(DOA) on the basis of separation, and has good performance under the low SNR. The simulation results show that the proposed method is effective．

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Fast detection of coherent signals using pre-conditioned root-MUSIC based on Toeplitz matrix reconstruction

2015 IEEE 11th International Conference on Wireless and Mobile Computing, Networking and Communications (WiMob) ◽

10.1109/wimob.2015.7347957 ◽

2015 ◽

Cited By ~ 5

Author(s):

A. Goian ◽

M. I. AlHajri ◽

R. M. Shubair ◽

L. Weruaga ◽

A. R. Kulaib ◽

...

Keyword(s):

Toeplitz Matrix ◽

Coherent Signals ◽

Fast Detection ◽

Matrix Reconstruction

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Localization of Coherent Signals Based on Toeplitz Matrix Reconstruction in Spatially Colored Nosie

2019 IEEE 2nd International Conference on Electronic Information and Communication Technology (ICEICT) ◽

10.1109/iceict.2019.8846348 ◽

2019 ◽

Author(s):

Ying-Ming Wang ◽

Shuai Liu ◽

Ming Jin

Keyword(s):

Toeplitz Matrix ◽

Coherent Signals ◽

Matrix Reconstruction

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On the Modular Operator of Mutli-component Regions in Chiral CFT

Communications in Mathematical Physics ◽

10.1007/s00220-021-04054-6 ◽

2021 ◽

Author(s):

Stefan Hollands

Keyword(s):

Field Theory ◽

Integral Equation ◽

Hilbert Problem ◽

Matrix Elements ◽

New Approach ◽

Conformal Field ◽

The Matrix ◽

Kms Condition ◽

Modular Operator ◽

Riemann Hilbert Problem

AbstractWe introduce a new approach to find the Tomita–Takesaki modular flow for multi-component regions in general chiral conformal field theory. Our method is based on locality and analyticity of primary fields as well as the so-called Kubo–Martin–Schwinger (KMS) condition. These features can be used to transform the problem to a Riemann–Hilbert problem on a covering of the complex plane cut along the regions, which is equivalent to an integral equation for the matrix elements of the modular Hamiltonian. Examples are considered.

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Development of High-Performance SiCp/Al-Si Composites by Equal Channel Angular Pressing

Metals ◽

10.3390/met8100738 ◽

2018 ◽

Vol 8 (10) ◽

pp. 738 ◽

Cited By ~ 5

Author(s):

Qiong Xu ◽

Aibin Ma ◽

Junjie Wang ◽

Jiapeng Sun ◽

Jinghua Jiang ◽

...

Keyword(s):

Wear Resistance ◽

Equal Channel Angular Pressing ◽

High Performance ◽

Adhesive Wear ◽

Processing Route ◽

Matrix Composites ◽

New Approach ◽

Angular Pressing ◽

The Matrix ◽

Industry Applications

Relatively low compactness and unsatisfactory uniformity of reinforced particles severely restrict the performance and widespread industry applications of the powder metallurgy (PM) metal matrix composites (MMCs). Here, we developed a combined processing route of PM and equal channel angular pressing (ECAP) to enhance the mechanical properties and wear resistance of the SiCp/Al-Si composite. The results indicate that ECAP significantly refined the matrix grains, eliminated pores and promoted the uniformity of the reinforcement particles. After 8p-ECAP, the SiCp/Al-Si composite consisted of ultrafine Al matrix grains (600 nm) modified by uniformly-dispersed Si and SiCp particles, and the composite relative density approached 100%. The hardness and wear resistance of the 8p-ECAP SiCp/Al-Si composite were markedly improved compared to the PM composite. More ECAP passes continued a trend of improvement for the wear resistance and hardness. Moreover, while abrasion and delamination dominated the wear of PM composites, less severe adhesive wear and fatigue mechanisms played more important roles in the wear of PM-ECAP composites. This study demonstrates a new approach to designing wear-resistant Al-MMCs and is readily applicable to other Al-MMCs.

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Internet Photogrammetry for Inspection of Seaports

Polish Maritime Research ◽

10.1515/pomr-2017-0036 ◽

2017 ◽

Vol 24 (s1) ◽

pp. 174-181 ◽

Cited By ~ 4

Author(s):

Zygmunt Paszotta ◽

Malgorzata Szumilo ◽

Jakub Szulwic

Keyword(s):

Fundamental Matrix ◽

Laser Scanning ◽

3D Models ◽

Digital Cameras ◽

Correct Orientation ◽

The Matrix ◽

Transport Safety ◽

Left And Right ◽

Value Decomposition ◽

The Relationship

Abstract This paper intends to point out the possibility of using Internet photogrammetry to construct 3D models from the images obtained by means of UAVs (Unmanned Aerial Vehicles). The solutions may be useful for the inspection of ports as to the content of cargo, transport safety or the assessment of the technical infrastructure of port and quays. The solution can be a complement to measurements made by using laser scanning and traditional surveying methods. In this paper the authors recommend a solution useful for creating 3D models from images acquired by the UAV using non-metric images from digital cameras. The developed algorithms, created and presented software allows to generate 3D models through the Internet in two modes: anaglyph and display in shutter systems. The problem of 3D image generation in photogrammetry is solved by using epipolar images. The appropriate method was presented by Kreiling in 1976. However, it applies to photogrammetric images for which the internal orientation is known. In the case of digital images obtained with non-metric cameras it is required to use another solution based on the fundamental matrix concept, introduced by Luong in 1992. In order to determine the matrix which defines the relationship between left and right digital image it is required to have at least eight homologous points. To determine the solution it is necessary to use the SVD (singular value decomposition). By using the fundamental matrix the epipolar lines are determined, which makes the correct orientation of images making stereo pairs, possible. The appropriate mathematical bases and illustrations are included in the publication.

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Curating Metal-Organic Frameworks to Compose Robust Gas Sensor Arrays in Dilute Conditions

10.26434/chemrxiv.8179244.v2 ◽

2019 ◽

Author(s):

Arni Sturluson ◽

Rachel Sousa ◽

Yujing Zhang ◽

Melanie T. Huynh ◽

Caleb Laird ◽

...

Keyword(s):

Sensor Array ◽

Gas Sensing ◽

Metal Organic Frameworks ◽

Sensor Arrays ◽

Gas Composition ◽

Composition Space ◽

The Matrix ◽

Metal Organic ◽

Analyte Detection ◽

Value Decomposition

Metal-organic frameworks (MOFs)-- tunable, nano-porous materials-- are alluring recognition elements for gas sensing. Mimicking human olfaction, an array of cross-sensitive, MOF-based sensors could enable analyte detection in complex, variable gas mixtures containing confounding gas species. Herein, we address the question: given a set of MOF candidates and their adsorption properties, how do we select the optimal subset to compose a sensor array that accurately and robustly predicts the gas composition via monitoring the adsorbed mass in each MOF? We first mathematically formulate the MOF-based sensor array problem under dilute conditions. Instructively, the sensor array can be viewed as a linear map from gas composition space to sensor array response space defined by the matrix H of Henry coefficients of the gases in the MOFs. Characterizing this mapping, the singular value decomposition of H is a useful tool for evaluating MOF subsets for sensor arrays, as it determines the sensitivity of the predicted gas composition to measurement error, quantifies the magnitude of the response to changes in composition, and recovers which direction in gas composition space elicits the largest/smallest response. To illustrate, on the basis of experimental adsorption data, we curate MOFs for a sensor array with the objective of determining the concentration of CO2 and SO2 in the gas phase.

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Impact Study on Social Accounting Matrix by Intrabusiness Analysis

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph182312547 ◽

2021 ◽

Vol 18 (23) ◽

pp. 12547

Author(s):

Monica Laura Zlati ◽

Romeo-Victor Ionescu ◽

Valentin Marian Antohi

Keyword(s):

Economic Systems ◽

Input Output ◽

Economic Sectors ◽

Output Analysis ◽

Regional Economic ◽

New Approach ◽

The Matrix ◽

The Government ◽

Current Concerns

According to the current concerns about social welfare and environmental protection, integrated in a model assimilated to intrabusiness relations, our research started from the analysis of the initial model SAM, which will be transformed in order to develop the SAMI model under six research objectives. The need of improving SAM matrix started to connect it directly to the regional economic systems and continued to a new approach on Input-Output Analysis. Nowadays, SAM describes the intraregional connections between regional economic actors using the role of different income categories. Moreover, SAM can quantify different regional multipliers. All deficiencies previously identified in connection to SAM model have been reviewed and resolved within the proposed SAMI model by the authors of this paper. The purpose of this research is the launch of an absolutely new mathematical model (SAMI) and its practical testing at regional level. This model is able to systematize the links between the local and regional businesses, under the matrix (SAMI) flow, for all kinds of companies and to assist the regional decision, as well. Czamanski was not able to escape from the input-output prison’s approach. This is why he continued to use the linear interdependencies between the industries, economic sectors and economic actors. The income is able only to approximate the individuals and other economic actors’ welfare. If the increase in the average and aggregate income is doubled by an unfair distribution of income in two countries which have the same average income, the effects on welfare vary a lot. A relatively similar effect comes from the government policy differences in income distribution and redistribution.

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Laser direct writing of nanocompounds

MRS Proceedings ◽

10.1557/opl.2011.1221 ◽

2011 ◽

Vol 1365 ◽

Author(s):

Andreas Ostendorf ◽

M’Barek Chakif ◽

Qingchuan Guo

Keyword(s):

Polymer Materials ◽

Polymerization Process ◽

Direct Writing ◽

Laser Direct Writing ◽

Bioactive Materials ◽

New Approach ◽

Photosensitive Polymer ◽

The Matrix ◽

Inorganic Nanomaterials ◽

Huge Variety

ABSTRACTLaser direct polymerization has been proven as a powerful tool to generate microstructures. Often photosensitive polymer materials are used because they can be tuned by photoactive molecules to be susceptible to a specific wavelength of light to initiate the polymerization process. One of the main drawbacks of this technique is the lack of functional polymers, e.g. conductive, magnetic, mechanical, optical or bioactive materials. Nanocomposites (nanocompounds), i.e. polymers with inorganic nanomaterials incorporated in the matrix offer a huge variety of new functionalities. A new approach will be presented how functional nanocomposite polymers can be generated and used for laser direct writing techniques. This can open the door for completely new MEMS and MOEMS devices comprising active and passive subcomponents.

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