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Social and Behavioral Sciences Commons

Open Access. Powered by Scholars. Published by Universities.®

Science and Technology Studies

University of Wollongong

2016

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Articles 1 - 4 of 4

Full-Text Articles in Social and Behavioral Sciences

Radar Imaging Of Stationary Indoor Targets Using Joint Low-Rank And Sparsity Constraints, Van Ha Tang, Abdesselam Bouzerdoum, Son Lam Phung, Fok Hing Chi Tivive Jan 2016

Radar Imaging Of Stationary Indoor Targets Using Joint Low-Rank And Sparsity Constraints, Van Ha Tang, Abdesselam Bouzerdoum, Son Lam Phung, Fok Hing Chi Tivive

Faculty of Engineering and Information Sciences - Papers: Part A

This paper introduces a joint low-rank and sparsity-based model to address the problem of wall-clutter mitigation in compressed through-the-wall radar imaging. The proposed model is motivated by two observations that wall reflections reside in a low-rank subspace, and target signals tend to be sparse. In the proposed approach, the task of segregating target returns from wall reflections is formulated as a joint low-rank and sparsity constrained optimization problem. Here, the low rank constraint is imposed on the wall component and the sparsity constraint is used to model the target component. An iterative soft thresholding algorithm is developed to estimate a …


Analysis Of Bacterial Diversity In Two Oil Blocks From Two Low-Permeability Reservoirs With High Salinities, Meng Xiao, Shan Shan Sun, Zhong Zhi Zhang, Junming Wang, Long Wei Qiu, Hua Yang Sun, Zhaozheng Song, Beiyu Zhang, De Li Gao, Guangqing Zhang, Wei Min Wu Jan 2016

Analysis Of Bacterial Diversity In Two Oil Blocks From Two Low-Permeability Reservoirs With High Salinities, Meng Xiao, Shan Shan Sun, Zhong Zhi Zhang, Junming Wang, Long Wei Qiu, Hua Yang Sun, Zhaozheng Song, Beiyu Zhang, De Li Gao, Guangqing Zhang, Wei Min Wu

Faculty of Engineering and Information Sciences - Papers: Part A

The community diversities of two oil reservoirs with low permeability of 1.81 x 10 '3 and 2.29 x 10 '3 1/4m 2 in Changqing, China, were investigated using a high throughput sequencing technique to analyze the influence of biostimulation with a nutrient activator on the bacterial communities. These two blocks differed significantly in salinity (average 17,500 vs 40,900 mg/L). A core simulation test was used to evaluate the effectiveness of indigenous microbial-enhanced oil recovery (MEOR). The results indicated that in the two high salinity oil reservoirs, one reservoir having relatively lower salinity level and a narrow salinity range had higher …


Indoor Scene Reconstruction For Through-The-Wall Radar Imaging Using Low-Rank And Sparsity Constraints, Van H. Tang, Abdesselam Bouzerdoum, Son Lam Phung, Fok Hing Chi Tivive Jan 2016

Indoor Scene Reconstruction For Through-The-Wall Radar Imaging Using Low-Rank And Sparsity Constraints, Van H. Tang, Abdesselam Bouzerdoum, Son Lam Phung, Fok Hing Chi Tivive

Faculty of Engineering and Information Sciences - Papers: Part A

This paper addresses the problem of indoor scene reconstruction in compressed sensing through-the-wall radar imaging. The proposed method is motivated by two observations that wall reflections reside in a low-rank subspace and the imaged scene tends to be sparse. The task of mitigating the wall reflections and reconstructing an image of the scene behind-the-wall is cast as a joint low-rank and sparsity constrained optimization problem, where a low-rank matrix captures the wall returns and a sparse matrix represents the formed image. An iterative algorithm is developed to estimate the low-rank matrix and the sparse scene vector from a reduced measurement …


Transient Cfd Modelling Of Low-Temperature Spontaneous Heating Behaviour In Multiple Coal Stockpiles With Wind Forced Convection, Jian Zhang, Yuntao Liang, Ting X. Ren, Zhongwei Wang, Gongda Wang Jan 2016

Transient Cfd Modelling Of Low-Temperature Spontaneous Heating Behaviour In Multiple Coal Stockpiles With Wind Forced Convection, Jian Zhang, Yuntao Liang, Ting X. Ren, Zhongwei Wang, Gongda Wang

Faculty of Engineering and Information Sciences - Papers: Part A

Spontaneous heating of coal stockpile has long been a thermal dynamic hazard during coal storage, processing, and transport. A transient non-equilibrium thermal CFD model has been developed to study the low-temperature self-heating behaviour of coal in multiple stockpiles under different prevailing wind conditions. Modelling results from the initial steady wind flow simulation indicate that a wake region can be induced on the leeward side of each coal stockpile. Pressure coefficient drops when the wind stream encounters or leaves a stockpile and the pressure coefficient profiles of multiple stockpiles tend to have more resemblance with a wider spacing. The first stockpile …