Hepatitis C virus (HCV) NS5B polymerase is an important and attractive target for the development of anti-HCV drugs. Here we report on the design, synthesis and evaluation of twenty-four novel allosteric inhibitors bearing the 4-thiazolidinone scaffold as inhibitors of HCV NS5B polymerase. Eleven compounds tested were found to inhibit HCV NS5B with IC50 values ranging between 19.8 and 64.9 μM. Compound 24 was the most active of this series with an IC50 of 5.6 μM. A number of these derivatives further exhibited strong inhibition against HCV 1b and 2a genotypes in cell based antiviral assays. Molecular docking analysis predicted that the thiazolidinone derivatives bind to the NS5B thumb pocket-II (TP-II). Our results suggest that further optimization of the thiazolidinone scaffold may be possible to yield new derivatives with improved enzyme- and cell-based activity.

In this work, physical parameter-based modeling of small signal parameters for a metal-semiconductor field-effect transistor (MESFET) has been carried out as continuous functions of drain voltage, gate voltage, frequency, and gate width. For this purpose, a device simulator has been used to generate a big dataset of which the physical device parameters included material type, doping concentration and profile, contact type, gate length, gate width, and work function. Five state-of-the-art algorithms: multi-layer perceptron (MLP), IBk, K * , Bagging, and REPTree have been used for creating a regression model. The symbolic regression algorithm has been used to obtain analytical expressions of the real and imaginary parts of the Scattering (S) parameters using the physics-based generated dataset. The regression performances of all the benchmarks and the symbolic regression have been compared to references from the device simulator results. The results of the derived equations and the best algorithms have been then compared to the device simulator results, with case studies for validation. The DC performance characteristics of the MESFET have been also obtained. The proposed model can be used to predict the small signal parameters of new devices prior to development, and allows for both the device and circuit to be optimized for specific applications.

In this paper, various physical device simulation of pseudomorphic High Electron Mobility Transistors are realized to show the effect of aligning parameter on scattering parameters. S parameters are complex numbers, so both real and imaginer part of scattering parameters are plotted concerning frequency at different align parameters. In all figures, a brief explanation about the change of the S parameter for frequency and align parameter is provided. The effect of the align parameter, which has a value of 0.4 differs from other align parameter values such as 0.45, 0.5, 0.55 and 0.6 on scattering parameters of the transistor structure.

Bu çalışmada Ku alt frekans bandında mikro şerit dizi anten için eş genlikli ve eş faz olacak şekilde bir besleme ağı yapısı ortaya konmuştur. Besleme ağı 8x4 toplam 32 elemanı besleyecek şekilde paralel besleme ağı kullanılarak tasarlanmıştır. Paralel besleme ağı her bir birim antene eş faz sağlaması ve anten dizisinin ışıma paterninde geniş tarafı öne gelecek şekilde ışıma yapması sağlanmıştır. Besleme ağı yapısı yaklaşık 1 desibellik bir uyumsuzlukla her bir antene güç paylaşımı sağlamayı başarmıştır. Besleme ağının gerçek performansını sağlamak için anten dizisiyle birleştirilmesi gerekmektedir. Bunun için açıklık kuplaj ile beslenen mikro şerit birim anten en uygun kazanç, yan lob seviyesi, bant genişliği ve empedans uyumu olacak şekilde tasarlanmıştır. Tasarımlanan besleme ağı yapısı 32 elemanlı birim anten dizisiyle birleştirilmiştir. Sonuç olarak besleme ağı ve anten dizisi birleştirilmesiyle sistemin bant genişliği, kazancı ve giriş uyumsuzluk değeri istenilen seviyeye gelmiştir. Besleme ağı ve anten dizisinin 3 boyutlu olarak alttan ve üstten gösterimi verilmiştir.