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2021 ◽  
Author(s):  
Jathurshan Pradeepkumar ◽  
Mithunjha Anandakumar ◽  
Vinith Kugathasan ◽  
Andrew Seeber ◽  
Dushan N Wadduwage

A key challenge in optical microscopy is to image fast at high-resolution. To address this problem, we propose "Physics Augmented U-Net", which combines deep learning and structured illumination microscopy (SIM). In SIM, the structured illumination aliases out-of-band high-frequencies to the passband of the microscope; thus SIM captures some high-frequencies even when the image is sampled at low-resolution. To utilize these features, we propose a three-element method: 1) a modified U-Net model, 2) a physics-based forward model of SIM 3) an inference algorithm combining the two models. The modified U-Net architecture is similar to the seminal work, but the bottleneck is modified by concatenating two latent vectors, one encoding low-frequencies (LFLV), and the other encoding high-frequencies (HFLV). LFLV is learned by U-Net contracting path, and HFLV is learned by a second encoding path. In the inference mode, the high-frequency encoder is removed; HFLV is then optimized to fit the measured microscopy images to the output of the forward model for the generated image by the U-Net. We validated our method on two different datasets under different experimental conditions. Since a latent vector is optimized instead of a 2D image, the inference mode is less computationally complex. The proposed model is also more stable compared to other generative prior-based methods. Finally, as the forward model is independent of the U-Net, Physics Augmented U-Net can enhance resolution on any variation of SIM without further retraining.


Author(s):  
N. E. Staroverov ◽  
A. Y. Gryaznov ◽  
I. G. Kamyshanskaya ◽  
N. N. Potrakhov ◽  
E. D. Kholopova

A method for processing microfocus X-ray images is described. It is based on high-frequency filtration and morphological image processing, which increases the contrast of the X-ray details. One of the most informative X-ray techniques is microfocus X-ray. In some cases, microfocus X-ray images cannot be reliably analyzed due to the peculiarities of the shooting method. So, the main disadvantages of microfocus X-ray images are most often an uneven background, distorted brightness characteristics and the presence of noise. The proposed method for enhancing the contrast of fine image details is based on the idea of combining high-frequency filtering and morphological image processing. The method consists of the following steps: noise suppression in the image, high-frequency filtering, morphological image processing, obtaining the resulting image. As a result of applying the method, the brightness of the contours in the image is enhanced. In the resulting image, all objects will have double outlines. The method was tested in the processing of 50 chest radiographs of patients with various pathologies. Radiographs were performed at the Mariinsky Hospital of St. Petersburg using digital stationary and mobile X-ray machines. In most of the radiographs, it was possible to improve the images contrast, to highlight the objects boundaries. Besides, the method was applied in microfocus X-ray tomography to improve the information content of projection data and improve the reconstruction of the 3D image of the research object. In both the first and second cases, the method showed satisfactory results. The developed method makes it possible to significantly increase the information content of microfocus X-ray images. The obtained practical results make it possible to count on broad prospects for the method application, especially in microfocus X-ray.


2021 ◽  
Vol 32 ◽  
pp. 179-193
Author(s):  
Artur Tworek

The aim of the following article is to analyze the pronunciation of Dutch surnames by Polish native speakers. The research material consists of journalistic statements from the communicative-semantic area of sport that are present in public audiovisual mass media. The selected material guarantees the high frequency of its production and the associated perception within the real acts of communication. In particular, the examination includes Dutch sounds which either do not exist in Polish or occur in a different graphical-distributional context. The exemplary research results (the mode of phonetic integration of foreign speech sounds) represent mechanisms that are interpreted in relation to typical communication models. The study also analyzes the potential placement of such phonetic forms in the target language, i.e. Polish.


2022 ◽  
Vol 15 (1) ◽  
pp. 1-31
Author(s):  
Philippos Papaphilippou ◽  
Jiuxi Meng ◽  
Nadeen Gebara ◽  
Wayne Luk

We present Hipernetch, a novel FPGA-based design for performing high-bandwidth network switching. FPGAs have recently become more popular in data centers due to their promising capabilities for a wide range of applications. With the recent surge in transceiver bandwidth, they could further benefit the implementation and refinement of network switches used in data centers. Hipernetch replaces the crossbar with a “combined parallel round-robin arbiter”. Unlike a crossbar, the combined parallel round-robin arbiter is easy to pipeline, and does not require centralised iterative scheduling algorithms that try to fit too many steps in a single or a few FPGA cycles. The result is a network switch implementation on FPGAs operating at a high frequency and with a low port-to-port latency. Our proposed Hipernetch architecture additionally provides a competitive switching performance approaching output-queued crossbar switches. Our implemented Hipernetch designs exhibit a throughput that exceeds 100 Gbps per port for switches of up to 16 ports, reaching an aggregate throughput of around 1.7 Tbps.


2021 ◽  
Vol 9 (34) ◽  
pp. 10566-10575
Author(s):  
Jeong Hwan Kim ◽  
Won Hyeok Choe ◽  
Sun-Young Lee ◽  
So Young Kwon ◽  
In-Kyung Sung ◽  
...  

Author(s):  
E. Paic ◽  
G. Vernardos ◽  
D. Sluse ◽  
M. Millon ◽  
F. Courbin ◽  
...  
Keyword(s):  

2021 ◽  
Vol 20 (3) ◽  
pp. 49-56
Author(s):  
A. A. Kazbanov ◽  
P. A. Dronov ◽  
O. O. Spivak ◽  
A. B. Derkachev

Testing of prototypes of equipment is the most important stage of their development. The article considers a low-power high-frequency ion engine RD0310 which was manufactured and tested at the production base of the KBHA joint-stock company. The tests were carried out in a vacuum chamber with a volume of 5.66 m3, the vacuum pumping system of which allows for a pressure inside the chamber of no more than 110-5mm Hg. with xenon consumption of up to 0.7 mg/s, which is as close as possible to space conditions. During the tests, the cyclogram of starting and stopping the engine was worked out, and the thrust dependences on the flow rate of the working fluid, the power of the high-frequency generator and the voltage at the emission electrode were obtained. According to the test results, stable engine operation was achieved and the following values were obtained: the thrust of 9.1mN at a specific impulse of 3740 s.


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