A Survey on Digital Image Copy-Move Forgery Localization Using Passive Techniques

Digital images can be tampered easily with simple image editing software tools.Therefore,image forensic investigation on the authenticity of digital images’content is increasingly important.Copy-move is one of the most common types of image forgeries.Thus,an overview of the traditional and the recent copy-move forgery localization methods using passive techniques is presented in this paper.These methods are classified into three types:block-based methods,keypoint-based methods,and deep learning-based methods.In addition,the strengths and weaknesses of these methods are compared and analyzed in robustness and computational cost.Finally,further research directions are discussed.

Anti-Corrosion and Reconstruction of Surface Crystal Plane for Zn Anodes by an Advanced Metal Passivation Technique

For the aqueous Zn-ion battery,dendrite formation,corrosion,and interfacial parasitic reactions are major issues,which greatly inhibits their practical application.How to develop a method of Zn construction or treatment to solve these issues for Zn anodes are still great challenges.Herein,a simple and cheap metal passivation technique is proposed for Zn anodes from a corrosion science perspective.Similar to the metal anticorrosion engineering,the formed interfacial protective layer in a chemical way can sufficiently solve the corrosion issues.Furthermore,the proposed passivity approach can reconstruct Zn surface-preferred crystal planes,exposing more(002)planes and improving surface hydrophilicity,which inhibits the formation of Zn dendrites and hydrogen evolution effectively.As expected,the passivated Zn achieves outstanding cycling life(1914 h)with low voltage polarization(<40 mV).Even at 6 mA cm^(−2) and 3 mA h cm^(−2),it can achieve stable Zn deposition over 460 h.The treated Zn anode coupled with MnO_(2) cathode shows prominently reinforced full batteries service life,making it a potential Zn anode candidate for excellent performance aqueous Zn-ion batteries.The proposed passivation approach provides a guideline for other metal electrodes preparation in various batteries and establishes the connections between corrosion science and batteries.

Target-oriented Passive Localization Techniques Inspired by Terrestrial Arthropods: A Review

For centuries,researchers have been fascinated by how simple-minded arthropods pick up definite cues and locate a potential target in an instant.Contrary to the active echolocation of classical creatures,arthropods exhibit passive characteristics.They use spatially separated sensilla to cooperatively pinpoint target-generated signal sources such as sound,light,ground vibration,air disturbance,and thermal radiation.The paper introduces the localization mechanisms of typical terrestrial arthropods with diverse survival habits.Focusing on these special mechanisms,a series of theoretical models and advanced bionic equipment have been reviewed,and some key challenges and future directions are proposed.We believe that intensive study on arthropods can promote innovative development of miniaturized,low power-dissipation,and high-performance localization equipment,thereby enhancing and expanding current localization techniques.

Measurement of the echo reduction for underwater acoustic passive materials by using the time reversal technique

A measuring method of the echo reduction of passive materials by using the time reversal（TR） technique is presented. To measure the echo reduction of a sample with this approach, the received signals are firstly focused according to the TR theory. Then, the sample is removed and the TR processing is again employed to realize the focus of the received signal.Finally, the echo reduction of the sample is evaluated with these focusing signals. Besides, to calibrate the measured echo reduction via the TR technique, a standard sample is employed to measure a constant coefficient that only depends on the measurement environment. An aluminum plate sample and a steel plate sample with the same size of 1.1 mxl.O m x0.005 m axe tested in a wave guide tank. The experimental results show that the calibrated values are well consistent with theoretical results under the free field at the measured frequency range of0.5-20 kHz. The relative errors of all the measured values are less than 10% and the values of the expanded uncertainty are less than 1.5 dB. The TR processing focuses the energy in spatial domain and temporal domain, so it can be used to measure the echo reduction of passive materials in the environments with reflections induced by boundaries and low frequency sources.

Measurement of insertion loss for underwater acoustic passive materials with the time reversal technique

A method using the time reversal（TR） technique to measure the insertion loss（IL） of passive materials is presented.Firstly the received signals are focused according to the TR theory when there is not a sample between the source and the received array.Then,the sample is placed near the received array and the TR processing is again employed to realize the focus of the received signal.Finally,the IL of the sample is evaluated from these focusing signals.Because the TR processing can focus the energy in spatial domain and time domain,the method can be used to measure acoustic properties of passive materials in a waveguide tank with reflections induced by boundaries or with low source frequencies.Two samples with the same size of 1.1 m×1.0 m×5 mm are tested in the waveguide tank.The method is demonstrated by the comparison of the theoretical and the experimental results in the measured frequency range of 1-20 kHz.

Passivation method of 317L stainless steel used in medicine

The electrochemical performance of 317L stainless steel used in medicineunder different conditions of passivation (different contents of HNO_3 solution, differentpassivation time and different passivation temperatures) was studied. The results show that thepitting potential of 317L stainless steel used in medicine can reach about 1.0 V (SCE) whenelectrochemically tested in 0.9% NaCl solution after the steel was passivated in 30% HNO_3 solutionat 35℃ for 6 h, which indicates that the passivation film has a relatively strong resistance tocorrosion. The results also show that the corrosion resistance of the passivation film on thesurface of 317SS can be increased after suitable amount of K_2Cr_2O_7 is added into HNO_3passivation solution.