Electromagnetic Imaging for Inhomogeneous Dielectric Cylinder Buried in a Slab Medium

[[abstract]]The electromagnetic imaging of inhomogeneous dielectric cylinders buried in a slab medium is investigated. Dielectric cylinders of unknown permittivities are buried in second space and scattered a group of unrelated waves incident from first space where the scattered field is recorded. By proper arrangement of the various unrelated incident field, the difficulties of ill-posedness and nonlinearity are circumvented, and the permittivity distribution can be reconstructed through simple matrix operations. The algorithm is based on the moment method and the unrelated illumination method. Numerical results are given to demonstrate the capability of the inverse algorithm. They also show that the permittivity distribution of the cylinders can be successfully reconstructed even when the permittivity is fairly large. Good reconstructed results are obtained even in the presence of additive Gaussian noise in measured data. In addition, the effect of noise on the reconstruction result is also investigated.[[notice]]補正完畢[[incitationindex]]EI[[booktype]]紙

Time Domain Image Reconstruction for a Buried 2D Homogeneous Dielectric Cylinder Using NU-SSGA

[[abstract]]This article presents an image reconstruction approach for a buried homogeneous cylinder with arbitrary cross-section in half space. The computational method combines the finite difference time domain (FDTD) method and non-uniform steady state genetic algorithm (NU-SSGA) to determine the shape and location of the subsurface scatterer with arbitrary shape. The FDTD-subgirdding technique is implemented for modeling the shape of the cylinder more closely. The inverse problem is reformulated into an optimization problem and the global searching scheme NU-SSGA with closed cubic-spline is then employed to search the parameter space. A set of representative numerical results is presented for demonstrating that the proposed approach is able to efficiently reconstruct the electromagnetic properties of homogeneous dielectric scatterer even when the initial guess is far from the exact one. In addition, the effects of Gaussian noises on imaging reconstruction are also investigated.[[incitationindex]]SCI[[incitationindex]]EI[[booktype]]紙

Image reconstruction of inhomogeneous biaxial dielectric cylinders buried in a slab medium

100學年度研究獎補助論文[[abstract]]The image reconstruction of inhomogeneous biaxial dielectric cylinders buried in a slab medium is investigated. A biaxial dielectric cylinder of unknown permittivities buried in a slab scatters a group of unrelated incident waves from outside. The scattered field is recorded outside the slab. By proper arrangement of the various unrelated incident fields, the difficulties of ill-posedness and nonlinearity are circumvented, and the permittivity distribution can be reconstructed through simple matrix operations. The algorithm is based on the moment method and the unrelated illumination method. Numerical results are given to demonstrate the capability of the inverse algorithm. Good reconstructed results are obtained even in the presence of additive Gaussian random noise in measured data. In addition, the effect of noise on the reconstruction result is also investigated.[[incitationindex]]SCI[[incitationindex]]EI[[booktype]]紙

Comparative Study of Some Population-based Optimization Algorithms on Inverse Scattering of a Two-Dimensional Perfectly Conducting Cylinder in Slab Medium

[[abstract]]The application of four techniques for the shape reconstruction of a 2-D metallic cylinder buried in dielectric slab medium by measured the cattered fields outside is studied in the paper. The finite-difference time-domain (FDTD) technique is employed for electromagnetic analyses for both the forward and inverse scattering problems, while the shape reconstruction problem is transformed into optimization one during the course of inverse scattering. Then, four techniques including asynchronous particle swarm optimization (APSO), PSO, dynamic differential evolution (DDE) and self-adaptive DDE (SADDE) are applied to reconstruct the location and shape of the 2-Dmetallic cylinder for comparative purposes. The statistical performances of these algorithms are compared. The results show that SADDE outperforms PSO, APSO and DDE in terms of the ability of exploring the optima. However, these results are considered to be indicative and do not generally apply to all optimization problems in electromagnetics.[[incitationindex]]SCI[[incitationindex]]EI[[booktype]]紙本[[booktype]]電子

Effects of natto extract on endothelial injury in a rat model

Vascular endothelial damage has been found to be associated with thrombus formation, which is considered to be a risk factor for cardiovascular disease. A diet of natto leads to a low prevalence of cardiovascular disease. The aim of the present study was to investigate the effects of natto extract on vascular endothelia damage with exposure to laser irradiation. Endothelial damage both in vitro and in vivo was induced by irradiation of rose bengal using a DPSS green laser. Cell viability was determined by MTS assay, and the intimal thickening was verified by a histological approach. The antioxidant content of natto extract was determined for the free radical scavenging activity. Endothelial cells were injured in the presence of rose bengal irradiated in a dose-dependent manner. Natto extract exhibits high levels of antioxidant activity compared with purified natto kinase. Apoptosis of laser-injured endothelial cells was significantly reduced in the presence of natto extract. Both the natto extract and natto kinase suppressed intimal thickening in rats with endothelial injury. The present findings suggest that natto extract suppresses vessel thickening as a synergic effect attributed to its antioxidant and anti-apoptosis properties

結合GBIF與MaxEnt預測臺灣赤楊之適宜生育地

選擇合宜的植物種類是植生復育的關鍵第一步，利用新興的物種分布模擬 (SDM) 將有助於正確選擇樹種及確定適宜生育地以提供科學決策。本文以臺灣赤楊為例，使用免費易得的全球生物多樣性資訊機構(GBIF) 物種資料庫、最大熵 (MaxEnt) 物種分布軟體進行其生育地適宜度分析，結果顯示預測模型之準確度評估屬於良好等級 (AUC = 0.842)，所得之預測出現機率可加以繪製臺灣赤楊之生育地適宜度 (HSI) 分布圖，經9 處崩塌地鄰近區域植群調查資料驗證十分吻合，同時本文對未來物種分布模擬尚待解決之相關議題加以討論，期使本地原生植物在水土保持植生復育中更具科學基礎與發揮其應用潛力。Selecting appropriate species is the first key step for vegetation rehabilitation. Novel species distribution modeling (SDM) can assist in making scientific decisions to support species selection and predict suitable habitat. In this paper, we combine the open-access Global Biodiversity Information Facility (GBIF) database and MaxEnt modeling software to predict Alnus formorsana distribution. The results reveal that the accuracy assessment of our model is good within an area of 0.842 according to the receiver operating characteristic curve. We transform the predicted occurrence probability, through ArcGIS, to map the habitat suitability index (HSI) of Alnus formorsana that approximately corresponds with the observed vegetation in 9 nearby landslide areas. Based on our findings, we discuss the future challenges related to SDM. The proposed approach can be used in the future to facilitate proper application of native plants in soil and water conservation

Design and implementation of a real-time global tone mapping processor for high dynamic range video

ABSTRACT As the development in high dynamic range (HDR

Neonauclea reticulata

In this study, we investigated whether the protective effects of Neonauclea reticulata water extract against ultraviolet B (UVB) irradiation in human skin fibroblast cell cultures (Hs68) are governed by its ability to protect against oxidative stress and expression of matrix metalloproteinases (MMPs). We found that Neonauclea reticulata extract exhibited DPPH scavenging activity and inhibited AAPH-induced haemolysis of erythrocytes in a dose- and time-dependent manner. We also found that pretreatment of fibroblasts with Neonauclea reticulata water extract resulted in markedly lower levels of MMP-1, -3, and -9 expressions. Furthermore, our results indicate that Neonauclea reticulata extract inhibits the expression of MMPs by inhibiting ERK, JNK, and p38 phosphorylation. Our results also demonstrate that treatment with Neonauclea reticulata extract protects against UVB-induced depletion of collagen. In addition, Neonauclea reticulata extract did not have a cytotoxic effect. These findings indicate that the antioxidant activity of Neonauclea reticulata extract resulted in inhibition of MMP-1, -3, and -9 expressions and in increased levels of collagen activity. Our results suggest that Neonauclea reticulata extract can protect against photoaging