Underwater acoustic communication has multipath error because of reflection by sea-level and sea-bottom. The multipath of UWA channel causes signal distortion and error floor. In this paper, we proposed the compensation method of multipath effect using the impulse response of the UWA channel. As shown in simulation results, the performance of proposed compensation method is better than the performance of conventional method.
Abstract Most single‐image super‐resolution (SR) models suffer from the degradation of image restoration performance when restoring a high‐resolution (HR) image from a low‐resolution (LR) image downscaled using an unknown blur kernel. The spatially invariant blur kernel estimators have been proposed to predict the blur kernel to address this issue. Nevertheless, the spatially variant blur exists in the real‐world; thus, these blur kernel estimators are unsuitable for real‐world applications. Although the spatially variant blur kernel estimators have been proposed, SR models still suffer from performance degradation because these estimators do neither consider the consistency between surrounding blur kernels nor refine non‐parametric blur kernels as parameters. To address this problem, the authors propose a multiregression spatially variant blur kernel estimation based on inter‐kernel consistency. The proposed estimator consists of three parts: non‐parametric regression, an inter‐kernel consistency block, and parametric regression. Specifically, it predicts spatially variant blur kernels while considering the inter‐kernel consistency between nearby blur kernels. Our source codes with pretrained models are available on https://github.com/alsgur0720/multiregression .
Abstract We aimed to determine whether vitamin D levels before prostate biopsy have diagnostic value for clinically significant prostate cancer. The study cohort included patients who underwent prostate biopsy. A total of 224 patients were enrolled in our study, and serum vitamin D levels were measured from February 2016 to December 2019 in routine laboratory tests. To determine the relationship between vitamin D levels and the aggressiveness of prostate cancer, we used multivariate analysis. Based on the histopathological results, the serum vitamin D level was marginally lower in the group with higher positive cores and pT3 or higher, and the serum vitamin D level was significantly lower in the large tumor volume group. In the univariate analysis, the prostate cancer diagnosis rate was associated with low vitamin D levels. In clinically significant prostate cancer diagnosis, low vitamin D levels were found in the univariate (odds ratio [OR], 0.955; P<0.001) and multivariate (OR, 0.944; P=0.027) analyses. In conclusion, we found that the incidence of prostate cancer tends to increase as the vitamin D level is lower in the Asian population, and this is particularly helpful in diagnosing clinically significant prostate cancer.
Purpose: Bladder capacity is an important parameter in the diagnosis of lower urinary tract dysfunction. We aimed to determine whether the maximum bladder capacity (MCC) measured during a urodynamic study was affected by involuntary detrusor contraction (IDC) in patients with Lower Urinary Tract Symptoms (LUTS)/Benign Prostatic Hyperplasia (BPH).Methods: Between March 2020 and April 2021, we obtained maximum voided volume (MVV) from a 3-day frequency-volume chart, MCC during filling cystometry, and maximum anesthetic bladder capacity (MABC) during holmium laser enucleation of the prostate under spinal or general anesthesia in 139 men with LUTS/BPH aged >50 years. Patients were divided according to the presence of IDC during filling cystometry. We assumed that the MABC is close to the true value of the MCC, as it is measured under the condition of minimizing neural influence over the bladder.Results: There was no difference in demographic and clinical characteristics between the non-IDC (n=20) and IDC groups (n=119) (mean age, 71.5±7.4) (P>0.05). The non-IDC group had greater bladder volume to feel the first sensation, first desire, and strong desire than the IDC group (P<0.001). In all patients, MABC and MVV were correlated (r=0.41, P<0.001); however, there was no correlation between MCC and MABC (r=0.19, P=0.02). There was no significant difference in MABC between the non-IDC and IDC groups (P=0.19), but MVV and MCC were significantly greater in the non-IDC group (P<0.001). There was no significant difference between MABC and MVV (MABC-MVV, P=0.54; MVV/MABC, P=0.07), but there was a significant difference between MABC and MCC between the non-IDC and IDC groups (MABC-MCC, P<0.001; MCC/MABC, P<0.001).Conclusions: Maximum bladder capacity from a urodynamic study does not represent true bladder capacity because of involuntary contractions.
The recent emerging significance of the Internet of Things (IoT) demands sensor devices to be integrated with many different functional structures and devices while conserving their original functionalities. To this end, optical transparency and mechanical flexibility of sensor devices are critical requirements for optimal integration as well as high sensitivity. In this work, a transparent, flexible, and sensitive gas sensor building platform is introduced by using multilevel self-assembly of block copolymers (BCPs) and polystyrene (PS) colloids. For the demonstration of an H2 gas sensor, a hierarchically porous Pd metal mesh structure is obtained by overlaying the two different patterned template structures with synergistic, distinctive characteristic length scales. The hierarchical Pd mesh shows not only high transparency over 90% but also superior sensing performance in terms of response and recovery time owing to enhanced Pd-to-hydride ratio and short H2 diffusion lengths from the enlarged active surface areas. The hierarchical morphology also endows high mechanical flexibility while securing reliable sensing performance even under severe mechanical deformation cycles. Our scalable self-assembly based multiscale nanopatterning offers an intriguing generalized platform for many different multifunctional devices requiring hidden in situ monitoring of environmental signals.
This paper proposes three kinds of simplified complexity-reduced algorithms for a low density parity check (LDPC) decoder. First, sequential decoding using a partial group is proposed. Second, an early detection method for reducing the computational complexity is proposed. Finally, in order to support the high-speed systems, we implemented LDPC decoder using three algorithms by N=648, R=1/2. And the decoder runs at a clock speed of 10ns. Therefore we implemented the LDPC decoder with the decoding speed of 110Mbps.
Recently, several arbitrary-scale models have been proposed for single-image super-resolution. Furthermore, the importance of arbitrary-scale single image super-resolution is emphasized for applications such as satellite image processing, HR display, and video-based surveillance. However, the baseline integer-scale model must be retrained to fit the existing network, and the learning speed is slow. This paper proposes a network to solve these problems, processing super-resolution by restoring the high-frequency information lost in the remaining arbitrary-scale while maintaining the baseline integer scale. The proposed network extends an integer-scaled image to an arbitrary-scale target in the discrete cosine transform spectral domain. We also modulate the high-frequency restoration weights of the depthwise multi-head attention to use memory efficiently. Finally, we demonstrate the performance through experiments with existing state-of-the-art models and their flexibility through integration with existing integer-scale models in terms of peak signal-to-noise ratio (PSNR) and similarity index measure (SSIM) scores. This means that the proposed network restores high-resolution (HR) images appropriately by improving the image sharpness of low-resolution (LR) images.