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In this paper, estimation angle performance analysis of amplitude-comparison monopulse radar under additive noise effect is dealt with. When uncorrelated white noises are added to the squinted beams, the angle estimation performance is analyzed through the mean square error(MSE). The numerical integration-based mean square error result completely overlaps the Monte Carlo-based mean square error result, which corresponds to 99.8% of the Monte Carlo-based mean square error result. In addition, the mean square error analysis method based on numerical integration has a much faster operation time than the mean square error method based on Monte Carlo. the angle estimation performance of the amplitude comparison monopulse radar can be efficiently analyzed in various noise environments through the proposed numerical integration-based mean square error method. [ABSTRACT FROM AUTHOR]

The present study aims to evaluate the effects of satellite-based SST (OSTIA) assimilation on a regional ocean circulation model for the Yellow and East China Seas (YECS), using three different assimilation methods: the Ensemble Optimal Interpolation (EnOI), Ensemble Kalman Filter (EnKF), and 4-Dimensional Variational (4DVAR) techniques, which are widely used in the ocean modeling communities. The model experiments show that an improved initial condition by assimilating the SST affects the seasonal water temperature and water mass distributions of the YECS. In particular, the SST data assimilation influences the temperature structures horizontally and vertically in winter, thereby improving the behavior of the YS warm current water. This is due to the fact that during wintertime the water column is well mixed, which is directly updated by the SST assimilation. The model comparisons indicate that the SST assimilation can improve the model performance in resolving the subsurface structures in wintertime, but has a relatively small impact in summertime due to the strong stratification. The differences among the different assimilation experiments are obvious when the SST was sharply changed due to a typhoon passage. Overall, the EnKF and 4DVAR show better agreement with the observations than the EnOI. The relatively low performance of EnOI under storm conditions may be related with a limitation of EnOI method whereby an analysis is obtained from a number of climatological fields, and thus the typhoon-induced SST changes in short-time scales may not be adequately reflected in the data assimilation. [ABSTRACT FROM AUTHOR]

Purpose: This study compared and analyzed the risk factors that affect a wound healing group and healing failure group. Materials and Methods: From 2010 to 2018, 39 patients who had suffered a single toe amputation were evaluated retrospectively. The patients were divided into two groups (wound healing group and healing failure group - within at least 3 months following the amputation). Regarding the possible risk factors, age, gender, Wagner and Brodsky classifications, duration of diabetes mellitus, whether the patient had peripheral arterial occlusive disease (PAOD) or cardiovascular disease, body mass index, HbA1c, total cholesterol, estimated glomerular filtration rate (eGFR), blood urea nitrogen (BUN), smoking, and alcohol were investigated. Results: The mean duration of diabetes mellitus was 140 months in the healing group and 227 months in the healing failure group, and the duration of diabetes was significantly longer in the failure group (p=0.009). A significant difference in eGFR was observed between the two groups (59.17 mL/min/1.73 m² in the healing group and 31.1 mL/min/1.73 m² in the failure group) (p=0.022). Sixteen patients with PAOD were found, all 10 patients in the healing failure group were PAOD patients. Conclusion: To reduce the additional complications in single toe amputation patients, the underlying disease and appropriate treatment are the most important factors. In addition, a more proximal level of amputation also should be considered in cases of patients with PAOD, high BUN and low eGFR, and patients with long-term diabetes. [ABSTRACT FROM AUTHOR]

The SPICE (Sparse Iterative Covariance-based Estimation) algorithm estimates the azimuth angle by applying a sparse recovery method to the covariance matrix in the time domain. In this paper, we show how the SPICE algorithm, which was originally formulated in the time domain, can be extended to the frequency domain. Furthermore, we demonstrate, through numerical results, that the performance of the proposed algorithm is superior to that of the conventional frequency domain algorithm. [ABSTRACT FROM AUTHOR]

This paper is a study on PRF selection method to accurately detect the target in the target tracking mode of airborne radar. The proposed methods are an ‘optimization’ method to select the closest to the center of the allowable zone considering the uncertainty of the target distance and velocity prediction and a ‘quasi-optimization’ method to improve the real time performance. In addition, the characteristics of the proposed methods are compared and analyzed through cost function and calculation time [ABSTRACT FROM AUTHOR]

In general, users of design software such as Photoshop, search for information online when they want to obtain related knowledge. However, it is very difficult to find the exact information they want about designs because available knowledge sharing systems are very broad in what they manage, and it is rare that such systems would provide any design-specific Q&A or exchange of information functionality. In the paper we development a video based system for sharing design knowledge that supplies Q&A, lecture, knowledge trade function etc. utilizing multimedia like text, image and video reflecting the characteristics of design knowledge. The system are expected to contribute to the competitiveness of products through sharing design knowledge. In the near future the system will need to expand to a framework that can be shared with a variety of knowledge, as well as design knowledge. [ABSTRACT FROM AUTHOR]

The effect of new building on the HF direction finding(DF) is analyzed. Commercially available software is used to get array manifold of the HF DF system. The terrain, building and the array antenna system are modelled. New building near the antenna system is also modelled to see whether it actually has an effect on the performance of the DF system. MUSIC and interferometer DF algorithms have been employed. [ABSTRACT FROM AUTHOR]

There have been many studies on the direction-of-arrival(DOA) estimation algorithm using antenna arrays. Beamforming, Capon's method, maximum likelihood, MUSIC algorithms are the main algorithms for the DOA estimation. Recently, compressive sensing -based DOA estimation algorithm exploiting the sparsity of the incident signals has attracted much attention in the signal processing community. In this paper, the performance of the L1-SVD algorithm, which is based on fitting of the data matrix, is compared with that of the MUSIC algorithm. [ABSTRACT FROM AUTHOR]

Recently, there has been a growing interest in physical-biological ocean-modeling systems by communities in the fields of science and business. In this paper, we present preliminary results from a coupled physical-biological model for the Northwestern Pacific marginal seas. The ocean circulation component is an implementation of the Regional Ocean Modeling System (ROMS), and the lower trophic level ecosystem component is a Nutrient-Phytoplankton-Zooplankton-Detritus (NPZD) model. The ROMS-NPZD coupled system, with a 25 km resolution, is forced by climatological atmospheric data and predicts the physical variables and concentrations of nitrate, phytoplankton, zooplankton, and detritus. Model results are compared with remote-sensed sea surface temperature and chlorophyll, and with climatological sea surface salinity and nitrate. Our model adequately reproduces the observed spatial distribution and seasonal variability of nitrate and chlorophyll concentrations as well as physical variables, showing a high correlation in the East Sea (ES) and Kuroshio/Oyashio Extension (KOE) region but relatively low correlation in the Yellow Sea (YS) and East China Sea (ECS). Although some deficiencies were found in the biological components, such as the over/underestimation of the intensity of phytoplankton blooms in the ES and KOE/the YS and ECS, our system demonstrates the capability of the model to capture and record dominant seasonal variability in physical-biological processes and this holds out the promise of coming to a better understanding of such processes and making better predictions. [ABSTRACT FROM AUTHOR]

This paper presents a design method for thin but wideband absorbers using resistive sheets. Its equivalent circuit consists of a series RLC resonant circuit and a short-terminated transmission line. Based on this equivalent circuit, we presented the three conditions for an electromagnetic absorber which has a thickness less than a quarter wavelength and wide absorption bandwidth at center frequency. By using an root-finding algorithm, the equivalent resistance, capacitance, and inductance of the absorbers are obtained. These equivalent circuit values for the absorber surface can be realized by a 2D periodic cross-shaped structure which has required surface resistance. Using the design method, we have designed the absorber which has 18.75 mm( $67.5^{\circ}$ electrical length) thickness and 90 % absorption bandwidth of 116 % bandwidth at 3 GHz. [ABSTRACT FROM AUTHOR]