Hybrid Perturbation Strategy for Semi-Supervised Crowd Counting.

A simple yet effective semi-supervised method is proposed in this paper based on consistency regularization for crowd counting, and a hybrid perturbation strategy is used to generate strong, diverse perturbations, and enhance unlabeled images information mining. The conventional CNN-based counting methods are sensitive to texture perturbation and imperceptible noises raised by adversarial attack, therefore, the hybrid strategy is proposed to combine a spatial texture transformation and an adversarial perturbation module to perturb the unlabeled data in the semantic and non-semantic spaces, respectively. Moreover, a cross-distribution normalization technique is introduced to address the model optimization failure caused by BN layer in the strong perturbation, and to stabilize the optimization of the learning model.

Robust Leaderless Time-Varying Formation Control for Nonlinear Unmanned Aerial Vehicle Swarm System With Communication Delays.

This article investigates the tracking-oriented robust leaderless time-varying formation (TVF) control problem for unmanned aerial vehicle swarm systems (UAVSSs) with Lipschitz nonlinear dynamics under directed topology, where external disturbances are random and bounded, and communication delays (CDs) are bounded. In this article, a state-feedback control approach is adopted to make sure that a UAVSS forms a desired TVF and follows a specified trajectory when CDs and external disturbances occur. First, a novel PD-like formation control protocol with several unknown parameters and CDs is designed.

A Miniature Triaxial Fiber Optic Force Sensor for Flexible Ureteroscopy.

Objective: Design and evaluate a miniature triaxial fiber optic sensor which is integrated into the confined space at the tip of a flexible ureteroscope to measure the contact force during ureteroscopy.

Methods: A notched flexure of multilayer continuous beams is deliberately designed to modulate the sensor sensitivity to axial stiffness but not to lateral bending and torsion, and to avoid the crosstalk between axial and lateral forces. Its structure parameters are optimized by the finite element method to meet the needs of miniaturization and performance.

Signal Feature Analysis of Contact Force at the Tip of a Flexible Ureteroscope.

This paper presents a signal analysis approach to identify the contact objects at the tip of a flexible ureteroscope. First, a miniature triaxial fiber optic sensor based on Fiber Bragg Grating(FBG) is devised to measure the interactive force signals at the ureteroscope tip. Due to the multidimensional properties of these force signals, the principal components analysis(PCA) method is introduced to reduce dimensions.

Biological tissues identification from their spectral signals acquired by a Raman needle.

In this paper, biological tissues are discriminated based on their intrinsic Raman spectral features. First, a Raman needle, which comprises of a Raman probe and a puncture needle, is devised to insert into biological tissues and acquire their Raman spectral data. The Savitzky-Golay filter is used to remove the data noise, and an adaptive iterative penalized least squares method to rectify the baseline.