A coupling model and ADMM algorithm based on TGV and shearlet regularization term for MRI reconstruction

Rias-type bays are one of the most common coasts in Japan where aquacultures have been active due to sheltered geological shape with a deep bottom. The huge tsunami hit Sanriku Coast consisting of open rias-type bays near the epicenter facing Pacific Ocean on 11 March 2011. For recovering Sanriku Coast, it is important to include sustainability in its program. Satoumi is defined as the human use and management of coastal seas for high productivity while maintaining high biodiversity. Therefore, we proposed Satoumi approach to an open rias-type bay, Shizugawa Bay, in southern Sanriku Coast. We conducted scientific researches on mapping of coastal habitats and aquaculture facilities, hydrography, and material flows of nutrients, a minor element (Fe) and organic matters in the bay including those from the rivers and from the offshore waters. At the same time, Committee for Shizugawa Bay Management of Fishermen’s Cooperative of Miyagi Prefecture decided to decrease in aquaculture facilities for sustainable development of aquaculture. Based on these data, a physical-biological coupling model was used for calculating the number of aquaculture facilities that are suitable not only for yields but also for environments. These researches were established on strong collaborations among a fishermen’s’ cooperative, local governments and scientists. Results of this practice may help to realize sustainable coastal use of a rias-type bay.

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Systematic Analysis and Review of Magnetic Resonance Imaging (MRI) Reconstruction Techniques

Current Medical Imaging Formerly Current Medical Imaging Reviews ◽

10.2174/1573405616666210105125542 ◽

2021 ◽

Vol 16 ◽

Author(s):

Penta Anil Kumar ◽

R. Gunasundari ◽

R. Aarthi

Keyword(s):

Magnetic Resonance Imaging ◽

Magnetic Resonance ◽

Optimization Technique ◽

Motion Artifacts ◽

Reconstruction Technique ◽

Resonance Imaging ◽

Research Gaps ◽

Conventional Mri ◽

Mri Reconstruction ◽

Magnetic Resonance Imaging Mri

Background: Magnetic Resonance Imaging (MRI) plays an important role in the field of medical diagnostic imaging as it poses non-invasive acquisition and high soft-tissue contrast. However, the huge time is needed for the MRI scanning process that results in motion artifacts, degrades image quality, misinterpretation of data, and may cause uncomfortable to the patient. Thus, the main goal of MRI research is to accelerate data acquisition processing without affecting the quality of the image. Introduction: This paper presents a survey based on distinct conventional MRI reconstruction methodologies. In addition, a novel MRI reconstruction strategy is proposed based on weighted Compressive Sensing (CS), Penalty-aided minimization function, and Meta-heuristic optimization technique. Methods: An illustrative analysis is done concerning adapted methods, datasets used, execution tools, performance measures, and values of evaluation metrics. Moreover, the issues of existing methods and the research gaps considering conventional MRI reconstruction schemes are elaborated to obtain improved contribution for devising significant MRI reconstruction techniques. Results: The proposed method will reduce conventional aliasing artifacts problems, may attain lower Mean Square Error (MSE), higher Peak Signal-to-Noise Ratio (PSNR), and Structural SIMilarity (SSIM) index. Conclusion: The issues of existing methods and the research gaps considering conventional MRI reconstruction schemes are elaborated to devising an improved significant MRI reconstruction technique.

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An Algorithm Combining Analysis-based Blind Compressed Sensing and Nonlocal Low-rank Constraints for MRI Reconstruction

Current Medical Imaging Formerly Current Medical Imaging Reviews ◽

10.2174/1573405614666180130151333 ◽

2019 ◽

Vol 15 (3) ◽

pp. 281-291 ◽

Cited By ~ 1

Author(s):

Mei Sun ◽

Jinxu Tao ◽

Zhongfu Ye ◽

Bensheng Qiu ◽

Jinzhang Xu ◽

...

Keyword(s):

Compressed Sensing ◽

Signal Reconstruction ◽

Low Rank ◽

Mr Images ◽

Scanning Time ◽

Previous State ◽

Rank Approximation ◽

Mri Reconstruction ◽

Magnetic Resonance Imaging Mri ◽

Rank Constraints

Background: In order to overcome the limitation of long scanning time, compressive sensing (CS) technology exploits the sparsity of image in some transform domain to reduce the amount of acquired data. Therefore, CS has been widely used in magnetic resonance imaging (MRI) reconstruction. </P><P> Discussion: Blind compressed sensing enables to recover the image successfully from highly under- sampled measurements, because of the data-driven adaption of the unknown transform basis priori. Moreover, analysis-based blind compressed sensing often leads to more efficient signal reconstruction with less time than synthesis-based blind compressed sensing. Recently, some experiments have shown that nonlocal low-rank property has the ability to preserve the details of the image for MRI reconstruction. Methods: Here, we focus on analysis-based blind compressed sensing, and combine it with additional nonlocal low-rank constraint to achieve better MR images from fewer measurements. Instead of nuclear norm, we exploit non-convex Schatten p-functionals for the rank approximation. </P><P> Results & Conclusion: Simulation results indicate that the proposed approach performs better than the previous state-of-the-art algorithms.

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An alternative model of the vibronic coupling in octahedral complexes

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19881134 ◽

1988 ◽

Vol 53 (6) ◽

pp. 1134-1140

Author(s):

Martin Breza ◽

Peter Pelikán

Keyword(s):

Linear Regression ◽

Alternative Model ◽

Potential Surface ◽

Analytical Formula ◽

Coupling Model ◽

Regression Method ◽

Vibronic Coupling ◽

Linear Regression Method ◽

Active Systems ◽

Jahn Teller

It is suggested that for some transition metal hexahalo complexes, the Eg-(a1g + eg) vibronic coupling model is better suited than the classical T2g-(a1g + eg) model. For the former, alternative model, the potential constants in the analytical formula are evaluated from the numerical map of the adiabatic potential surface by using the linear regression method. The numerical values for 29 hexahalo complexes of the 1st row transition metals are obtained by the CNDO/2 method. Some interesting trends of parameters of such Jahn-Teller-active systems are disclosed.

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Development of an intermediate level cable coupling model

IET 7th International Conference on Computation in Electromagnetics (CEM 2008) ◽

10.1049/cp:20080259 ◽

2008 ◽

Author(s):

S.P. Watkins

Keyword(s):

Coupling Model ◽

Intermediate Level

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A Fusion Algorithm for Online Reliability Evaluation of Microgrid Inverter IGBT

Electronics ◽

10.3390/electronics9081294 ◽

2020 ◽

Vol 9 (8) ◽

pp. 1294 ◽

Cited By ~ 1

Author(s):

Chuankun Wang ◽

Yigang He ◽

Chenyuan Wang ◽

Xiaoxin Wu ◽

Lie Li

Keyword(s):

Aging Process ◽

Short Term Memory ◽

Coupling Model ◽

Reliability Evaluation ◽

Junction Temperature ◽

Stable Operation ◽

Practical Case ◽

Fusion Algorithm ◽

Insulated Gate Bipolar Transistor ◽

Damage Degree

Due to the diversity of distributed generation sources, microgrid inverters work under complex and changeable conditions. The core device of inverters, an insulated gate bipolar transistor (IGBT), bears a large amount of thermal stress impact, so its reliability is related to the stable operation of the microgrid. The effect of the IGBT aging process cannot be considered adequately with the existing reliability evaluation methods, which have not yet reached the requirements of online evaluation. This paper proposes a fusion algorithm for online reliability evaluation of microgrid inverter IGBT, which combines condition monitoring and reliability evaluation. Firstly, based on the microgrid inverter topology and IGBT characteristics, an electrothermal coupling model is established to obtain junction temperature data. Secondly, the segmented long short-term memory (LSTM) algorithm is studied, which can accurately predict the aging process of the IGBT and judge the aging state via the limited monitoring data. Then, the parameters of the electrothermal coupling model are corrected according to the aging process. Besides, the fusion algorithm is applied to the practical case. Finally, the data comparison verifies the feasibility of the fusion algorithm, whose cumulative damage degree and estimated life error are 5.10% and 5.83%, respectively.

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Predicting the number of fiber roots in lola drafting based on multi-field coupling

Textile Research Journal ◽

10.1177/0040517520930192 ◽

2020 ◽

Vol 90 (23-24) ◽

pp. 2769-2781

Author(s):

Xin rong Li ◽

LiuBo Wu ◽

Zhaoning Bu ◽

Lidong Liu

Keyword(s):

Change Point ◽

Production Efficiency ◽

Slip Rate ◽

Sharp Decrease ◽

Coupling Model ◽

Production Costs ◽

Weak Effect ◽

Field Coupling ◽

Theoretical Support ◽

New Type

Pullout theory is very important in improving efficiency, quality, and production costs. Because production efficiency is too low for mechanical drafting equipment, a simple multi-field coupling model of fiber mechanics based on conserving momentum is proposed that considers the distribution of the fiber speed point, slip rate, and friction mechanics. When the roller draft multiple is increased, the position near the rear roller clamp mouth in the draft area will show a sharp decrease of fiber, which is caused by the rapid movement of the front fiber to drive the floating fiber movement, and it is also the existence of the fiber change point. When the roller spacing increases, the draft efficiency decreases, although the pressure applied by the roller to the fibrous strip has a weak effect on the draft efficiency. This research increases our understanding of drawing and provides theoretical support for the design of a new type of drawing.

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Design and experiment of multi-mode steering system of agricultural machinery for hilly and mountainous area

Advances in Mechanical Engineering ◽

10.1177/16878140211034827 ◽

2021 ◽

Vol 13 (7) ◽

pp. 168781402110348

Author(s):

Kai Hu ◽

Wenyi Zhang

Keyword(s):

Negative Impact ◽

System Development ◽

Coupling Model ◽

Maximum Error ◽

Rear Wheel ◽

Steering System ◽

Mountainous Area ◽

Agricultural Machinery ◽

Hydraulic Cylinders ◽

Multi Mode

In order to improve the steering flexibility of agricultural machinery in hilly and mountainous areas, a multi-mode steering system with front wheel steering, rear wheel steering, and four-wheel steering has been developed. The hydraulic steering system based on load sensitivity principle and proportion-integration-differentiation (PID) controlling algorithm was designed, which overcomes the negative impact of external load changes on flow control accuracy. The mechanical-hydraulic-controlling coupling model established in the AMESim and the sequential quadratic combinatorial optimization algorithm (SQCOA) was adopted to obtain the optimal combination of PID parameters. The simulation results demonstrate that the parameters such as pressure, speed, displacement of hydraulic cylinders, etc. in different steering modes meet the design requirements. To examine and verify the system performance, the test platform was researched and developed for conducting steering radius and displacement measurement. The experimental data illustrated that the front and rear hydraulic cylinders have good synchronization accuracy in four-wheel steering mode, and the fast switch of steering mode can be realized. The maximum error rate of is steering radius 4.21% and 3.77%, respectively, in two-wheel steering and four-wheel steering modes. The research methods and conclusions can provide a theoretical basis and reference for the other steering system development.

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