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The size and shape of the foveal avascular zone (FAZ) have a strong positive correlation with several vision-threatening retinovascular diseases. The identification, segmentation and analysis of FAZ are of great significance to clinical diagnosis and treatment. We presented an adaptive watershed algorithm to automatically extract FAZ from retinal optical coherence tomography angiography (OCTA) images. For the traditional watershed algorithm, “over-segmentation” is the most common problem. FAZ is often incorrectly divided into multiple regions by redundant “dams”. This paper analyzed the relationship between the “dams” length and the maximum inscribed circle radius of FAZ, and proposed an adaptive watershed algorithm to solve the problem of “over-segmentation”. Here, 132 healthy retinal images and 50 diabetic retinopathy (DR) images were used to verify the accuracy and stability of the algorithm. Three ophthalmologists were invited to make quantitative and qualitative evaluations on the segmentation results of this algorithm. The quantitative evaluation results show that the correlation coefficients between the automatic and manual segmentation results are 0.945 (in healthy subjects) and 0.927 (in DR patients), respectively. For qualitative evaluation, the percentages of “perfect segmentation” (score of 3) and “good segmentation” (score of 2) are 99.4% (in healthy subjects) and 98.7% (in DR patients), respectively. This work promotes the application of watershed algorithm in FAZ segmentation, making it a useful tool for analyzing and diagnosing eye diseases.

In this brief, the silicon nanowire transistor (SNWT)-based circuits of current mirrors (NWCMs) have been successfully fabricated for the first time. The key figures of merit of current mirrors (CMs) are experimentally studied, including output voltage coefficient (OVC), output resistance, and dc matching error e. The experimental results indicate that, due to the unique quasi-1-D transport properties of the SNWTs, NWCMs exhibit superior performance than planar metal-oxide-semiconductor-field-effect-transistor-based CMs (PCMs) in the inversion operation region. Furthermore, NWCMs operating in the subthreshold region shows even better performance than PCMs. With the inherent advantages of the gate-all-around structure, the SNWT is very promising for analog and mixed-signal integrated circuits and particularly has its unique potential at subthreshold operation for low-power applications.

Shape controllable silicon nanowires (SiNWs) have been fabricated with CMOS compatible top-down fabrication process by carefully designing the oxidation temperature, time, and the original shape of Si wires. Higher oxidation temperature favors the formation of circular SiNWs, since the impact of oxidation retardation on the oxidation rate at sharp corners is reduced, and the discrepancy between the oxidation rates of different SiNW planes is minimized. In our work, high quality circular SiNWs with diameter of 5 nm have been successfully fabricated at high oxidation temperature of 950 °C. Pentagonal, triangular, and circular SiNWs with diameter around 10 nm have also been obtained at 950 °C by controlling the oxidation time and the original shape of the wires.

The deteriorated radiation effects of very deep-sub-micron (VDSM) MOS transistors with multi-finger are experimentally investigated for the first time. The results show that due to the interaction between reverse narrow channel effect and radiation induced edge effect, multi-finger transistors are more sensitive to radiation in comparison with standard MOSFETs. Larger threshold-voltage shift and higher leakage current are observed. The mechanisms responsible for the effects are briefly discussed. The results demonstrate that special radiation hardening technology should be adopted for multi-finger transistors operating in the radiation environment.

The gate-all-around (GAA) silicon nanowire transistor (SNWT) is considered as one of the best candidates for ultimately scaled CMOS devices. This paper discusses the process impact on nanowire LER/LWR, as well as the impact of 2D nanowire LER on performance variation and degradation. And it is found that SNWTs, which is immune to channel RDF(random dopant fluctuation), exhibit SDE-RDF which is enhanced by diameter-dependent annealing. In addition, the different impacts of the experimentally extracted variation sources in SNWTs on the threshold voltage and on current flucturation is discussed, as well as the variability impact on SNWT based SRAM cells compared with planar SRAM cells.

This paper discusses self-heating effect and variability behavior of GAA SNWTs. Due to the 1-D nature of nanowire and increased phononboundary scattering in GAA structure, the selfheating effect in SNWTs based on bulk substrate is comparable or even a little bit worse than SOI devices, which may limit the ultimate performance of SNWT-based circuits and thus special design consideration is expected. On the other hand, random variation has become a practical problem at nano-scale. The characteristic variability of SNWTs is experimentally extracted and studied in detail. And the impacts of nanowire LER, the diameter-dependent annealing enhanced nanowire This paper discusses self-heating effect and variability behavior of GAA SNWTs. Due to the 1-D nature of nanowire and increased phononboundary scattering in GAA structure, the selfheating effect in SNWTs based on bulk substrate is comparable or even a little bit worse than SOI devices, which may limit the ultimate performance of SNWT-based circuits and thus special design consideration is expected. On the other hand, random variation has become a practical problem at nano-scale. The characteristic variability of SNWTs is experimentally extracted and studied in detail. And the impacts of nanowire LER, the diameter-dependent annealing enhanced nanowire

With the comprehensive development of Next Generation Network (NGN), voice calls on IPv6 (VoIP over IPv6) is the general trend. This paper studies the core Signalling Conrol Protocol of NGN-SIP features and structure, analyzes the model based on SIP, researches the framework of voice within SIP, eventually proposed the way to complete VoIP in the environment of IPv6 with VC++.

Vertical Si nano-rings with a uniform thickness of about 100 nm have been fabricated by conventional optical photolithography with a low cost based on Poisson diffraction. Moreover, the roughness of the Si nano-rings can be effectively reduced by sacrificial oxidation. In order to increase the density of the nano-rings, coaxial twin Si nano-rings have been fabricated by the Poisson diffraction method combined with the spacer technique. The thickness of both the inner and outer Si nano-rings is about 60 nm, and the gap between the twin nano-rings is about 100 nm.