Characterization of Counter-Surface Substrates for a Laboratory Abrasion Tester (LAT100) Compared with Asphalt and Concrete to Predict Car Tire Performance

Tire performance is determined based on the interaction between the tire and the road as a counter-surface, and is of the utmost importance for driving safety. When studying tire friction and abrasion, the characteristics of the roads/counter-surfaces are crucial. The excitations on the tire come from the road asperities. A proper characterization of the counter-surface texture is, therefore, an absolute necessity in order to optimize tire performance. The present study provides the required knowledge over the counter-surfaces employed as common substrates in a Laboratory Abrasion Tester (LAT100), which are typically based on embedded corundum particles for dry/wet friction and abrasion experiments. All surfaces are scanned and characterized by laser microscopy. The surface micro and macro roughness/textures are evaluated and compared with asphalt and concrete as the real roads by power spectral densities (PSD). The reliability of the high-frequency data based on the device type should be considered carefully. The reliable cut-off wavenumber of the PSDs is investigated based on image analyses on the range of tested frequency for micro and macro textures obtained by optical scanning devices. The influence of the texture wavelength range on the rubber−surface interaction is studied on a laboratory scale.

Asymmetric Cryptosystem Based on Optical Scanning Cryptography and Elliptic Curve Algorithm

We propose an asymmetric cryptosystem based on optical scanning cryptography (OSC) and elliptic curve cryptography (ECC) algorithm. In the encryption stage of OSC, an object is encrypted to cosine and sine holograms by two pupil functions calculated via ECC algorithm from sender’s biometric image, which is sender’s private key. With the ECC algorithm, these holograms are encrypted to ciphertext, which is sent to the receiver. In the stage of decryption, the ciphered holograms can be decrypted by receiver’s biometric private key which is different from the sender’s private key. The approach is an asymmetric cryptosystem which solves the problem of the management and dispatch of keys in OSC and has more security strength than it. The feasibility of the proposed method has been convincingly verified by numerical and experiment results.

Effects of Water Cooling on the Microstructure of Electron Beam Additive-Manufactured Ti-6Al-4V

The inferior mechanical properties of EBAM Ti-6Al-4V samples are due to the coarse columnar grains containing coarse lamellar structures. One can expect that water cooling of the build platform will increase the cooling rate of the molten pool during the build-up process, causing microstructure refinement. In the present work, the substrate cooling effects on the microstructure and phase composition of EBAM Ti-6Al-4V samples are studied using optical, scanning electron, and scanning transmission microscopy, as well as X-ray diffraction analysis. It is shown that the microstructure of the EBAM Ti-6Al-4V samples built on the substrate without water cooling consists predominantly of columnar prior β grains with lateral sizes ranging up to 2000 µm, while cooling of the build platform causes the appearance of equiaxed prior β grains measuring 1000 µm. Moreover, the refinement of the martensite structure and the precipitation of α″ martensite platelets within a laths occur in the EBAM Ti-6Al-4V samples built on the water-cooled build platform. An explanation of the mechanisms underlying the α′→α + β and α′→α + α″ + β transformations during the building process is provided based upon ab initio calculations. The fragmentation of the a laths under the residual compressive stresses is discussed.

Case Study on Large Ingots Cracking Failure

Use of Metal and its alloys have become the need of this world. high strength pipes and equipment are required for the extraction of bituminous oil from soil. For this High strength Low Alloy Steel (Micro-alloyed steels) can be used. HSLA required large size ingots for its manufacturing therefore in recent years, large size ingots demand is increased. Large size ingots are subjected to cracking while manufacturing during open die forging process. Optical Scanning Electron Microscopies and Energy dispersion Spectroscopy techniques are carried out for the investigation of root causes of the cracking during forging of large size ingots. Microstructure of large size ingots sample are reviewed at different locations and grain boundaries. Results of these chemical techniques shows the enrichment of chromium and oxygen content at the boundaries which clearly differentiated a cracked boundary and non-cracked locations. This writing comprises the literature study, test procedures and analyzing the results to review that abnormal grain growth was the cause of cracking of large size ingots during forging process. The report also reviewed, alternate heat treatments and possible solution.

Deep Convolutional Sequence Approach Towards Real-Time Intelligent Optical Scanning

Visual text recognition is the most dynamic computer vision application due to its rising demand in several applications like crime scene detection, assisting blind people, digitizing, book scanning, etc. However, numerous research works were executed on static visuals having organized text and on captured video frames in the past. The key objective of this study is to develop the real-time intelligent optical scanner that will extract every sequence of text from high-speed video, noisy visual input, and offline handwritten script. The scientific work has been carried out with the combination of multiple deep learning approaches, namely EAST, CNN, and Bi-LSTM with CTC. The system is trained and tested on four public datasets (i.e., ICDAR 2015, SVT, Synth-Text, IAM-3.0) and measured on the basis of recall, precision, and f-measure. Based on the challenges, performance has been examined under three different categories, and the outcomes are optimistic and encouraging for future advancement.