Mainlobe jamming suppression method based on beamspace orthogonal cancellation for distributed array radar

The Saudi Arabian Glass Earth Pilot Project is a geophysical exploration program to explore the upper crust of the Kingdom for minerals, groundwater, and geothermal resources as well as strictly academic investigations. The project began with over 8000 km2 of green-field area. Airborne geophysics including electromagnetic (EM), magnetics, and gravity were used to develop several high priority targets for ground follow-up. Based on the results of airborne survey, a spectral induced polarization (SIP) survey was completed over one of the prospective targets. The field data were collected with a distributed array system, which has the potential for strong inductive coupling. This was examined in a synthetic study, and it was determined that with the geometries and conductivities in the field survey, the inductive coupling effect may be visible in the data. In this study, we also confirmed that time domain is vastly superior to frequency domain for avoiding inductive coupling, that measuring decays from 50 ms to 2 s allow discrimination of time constants from 1 ms to 5 s, and the relaxation parameter C is strongly coupled to intrinsic chargeability. We developed a method to fully include all 3D EM effects in the inversion of induced polarization (IP) data. The field SIP data were inverted using the generalized effective-medium theory of induced polarization (GEMTIP) in conjunction with an integral equation-based modeling and inversion methods. These methods can replicate all inductive coupling and EM effects, which removes one significant barrier to inversion of large bandwidth spectral IP data. The results of this inversion were interpreted and compared with results of drill hole set up in the survey area. The drill hole intersected significant mineralization which is currently being further investigated. The project can be considered a technical success, validating the methods and effective-medium inversion technique used for the project.

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Cluster-Type Photovoltaic Inverter Resonance Suppression Method Based on Adaptive Notch

Proceedings of the 2nd International Conference on Information Technologies and Electrical Engineering ◽

10.1145/3386415.3387048 ◽

2019 ◽

Author(s):

Shengqing Li ◽

Zhichao Shen ◽

Ziran Peng ◽

Yuanming He ◽

Xinpeng Gu ◽

...

Keyword(s):

Suppression Method ◽

Cluster Type

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Disentangled generative adversarial network for low-dose CT

EURASIP Journal on Advances in Signal Processing ◽

10.1186/s13634-021-00749-z ◽

2021 ◽

Vol 2021 (1) ◽

Author(s):

Wenchao Du ◽

Hu Chen ◽

Hongyu Yang ◽

Yi Zhang

Keyword(s):

Network Architecture ◽

Low Dose ◽

Noise Suppression ◽

State Of The Art ◽

Visual Quality ◽

Ct Images ◽

Generative Adversarial Network ◽

Low Dose Ct ◽

Adversarial Network ◽

Suppression Method

AbstractGenerative adversarial network (GAN) has been applied for low-dose CT images to predict normal-dose CT images. However, the undesired artifacts and details bring uncertainty to the clinical diagnosis. In order to improve the visual quality while suppressing the noise, in this paper, we mainly studied the two key components of deep learning based low-dose CT (LDCT) restoration models—network architecture and adversarial loss, and proposed a disentangled noise suppression method based on GAN (DNSGAN) for LDCT. Specifically, a generator network, which contains the noise suppression and structure recovery modules, is proposed. Furthermore, a multi-scaled relativistic adversarial loss is introduced to preserve the finer structures of generated images. Experiments on simulated and real LDCT datasets show that the proposed method can effectively remove noise while recovering finer details and provide better visual perception than other state-of-the-art methods.

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