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In many measurement applications using multicameras, there is often a nonoverlapping field of view (nFOV) between multicameras. It benefits greatly from having all of the cameras unified in a single coordinate frame by means of common spatial constraints. However, it is very difficult to establish common spatial constraints for accurate and quick calibration of the extrinsic parameters between multicameras in the case of long working distance, asymmetric working angle, or limited working space. To overcome these issues, we propose a flexible calibration method using a camera rig, which can be easily modeled as a hand–eye calibration problem and solved by only several sets of calibration images. To further improve the calibration accuracy, the camera intrinsic parameters, lens distortion coefficients, and extrinsic parameters are optimized simultaneously, similar to binocular calibration. However, this causes calculation instability of multiparameters. We extend the epipolar constraint to two images with an nFOV and add it into the optimization objective function together with the reprojection error, which ensures the basic consistency of intrinsic parameters before and after optimization, and reduce the fluctuation caused by the number of images involved in calibration. Experiments and application have proved that the proposed new methods are feasible and effective. [ABSTRACT FROM AUTHOR]

This paper proposed, for the first time, that the band-edge effective work functions (EWFs) are achieved by employing PH3 plasma doping (PLAD) TiN metal gate for nMOS device application under replacement metal gate and high dielectric constant (k) dielectric/metal gate last nMOS device. The effects of PLAD energy, dose, gas mixture, and postdoping cleaning procedure on the EWF, EOT, and properties of TiN/HfO2/ILSiO2 gate-stack are investigated; the corresponding possible mechanisms are discussed. Suitable low threshold voltages of nMOSFETs are obtained, while shrinking the EOT. It reduces the corner effect on trench gate doping uniformity, which is induced by shadowing effect in the beam-line implantation technology, to a minimum. It has the potential for the further aggressively scaled 3-D CMOS device and beyond application. [ABSTRACT FROM AUTHOR]

Most distributed parameter systems (DPS) have a strongly nonlinear spatiotemporal nature and are affected by disturbance. However, most of the existing DPS modeling methods only consider the linear relation between the spatial positions, but neglect the nonlinear one. Additionally, they also do not account for the influence of disturbance. Thus, in this paper, a robust spatiotemporal least squares support vector machine (LS-SVM) modeling method for DPS with disturbance is proposed. First, a spatial kernel function is constructed in order to describe the nonlinear relation between spatial positions. An optimal fusion method is then developed to derive a robust temporal coefficient, from which the influence of disturbance can be rejected. Through the integration of the spatial kernel function and the robust temporal coefficient, a robust spatiotemporal LS-SVM model is constructed. Since this modeling not only considers the nonlinear nature but also takes the influence of disturbance into account, it has the ability to adapt well to the nonlinear spatiotemporal dynamics, even when disturbance is presented. The analysis and proof show that the proposed robust spatiotemporal LS-SVM modeling method has the better robust performance as compared to the existing ones. Case studies not only demonstrate the effectiveness of the proposed method, but also demonstrate its superior robustness than other conventional modeling methods. [ABSTRACT FROM AUTHOR]

Deals with a study which examined the use of unipolar codes with ideal in-phase cross-correlation in spectral amplitude-coding optical code-division multiple-access systems. Background on the theoretical analyses of optical code-division multiple-access systems; Information on the modified quadratic congruence code; Code evaluation and comparison.

In the existing millimeter-wave (mmWave) wireless positioning systems, the method based on sparse Bayesian learning (SBL) uses the channel sparsity to estimate the parameters required for positioning, such as angle of arrival (AOA) and time delay, but most existing SBL solutions only consider the angle sparsity. In this paper, we consider the joint sparsity of the angle domain and time delay domain to propose an improved SBL algorithm by using a new two-dimensional adaptive grid refinement method in the SBL framework. This algorithm solves the grid mismatch problem caused by the fixed grid in the traditional SBL method, and reduces the algorithm complexity of the off-grid SBL (OGSBL) algorithm. We also obtain the Cramér-Rao bound (CRB) of AOA, time delay and position estimation based on the mmWave multipath signals to analyze the estimation errors. Simulation results show that the performance of the proposed algorithm is better than existing algorithms and can approach CRB. [ABSTRACT FROM AUTHOR]

This article focuses on automatic inspection for the commonly used component called spring-wire socket. An automatic inspection system is built that adopts an endoscope to improve the imaging quality. To detect the low contrast targets in complex background, we adopt the pipeline of Faster R-CNN but with several improvements. The improved network specifies the targets in the form of quadrangular bounding box as opposed to previous methods that specify them by rectangular bounding box. With the quadrangular representation, additional shape and pose information is provided and unexpected overlaps and background disturbance could be avoided. In the network, an eight-dimensional (8-D) vector is designed to represent the quadrangular bounding box followed by the improved anchor mechanism in the region proposal network. And also, a novel overlap score calculation method is proposed. On the basis of the detection result, rules arisen from expertise are provided to determine the quality of the component in which way automatic quality inspection could be accomplished. The superiority of our detection network over existing ones is sufficiently demonstrated with the detection result of irregular targets in images captured in the industrial scenario. Meanwhile, successful inspection result proves that the system meets the industrial requirements in terms of both accuracy and speed and thus is of practical significance to industrial applications. [ABSTRACT FROM AUTHOR]

Plasma doping (PLAD), a high-throughput ion implantation technique capable of achieving ultrashallow junctions and conformal doping of 3-D structures such as fin field-effect transistors, is investigated as an alternative to conventional beam-line ion implantation for InGaAs at advanced technology nodes. The PLAD at an elevated substrate temperature (ET-PLAD) is studied and reported for InGaAs for the first time. The ET-PLAD can give lower sheet resistance than room-temperature PLAD due to enhanced dopant incorporation. More crucially, an ET can help to prevent amorphization. After dopant activation anneal, residual corner defects are observed in small fins that are amorphized during plasma ion implantation, whereas fins that remain crystalline during plasma ion implantation are free of corner defects. [ABSTRACT FROM PUBLISHER]