High-Speed Decoding Algorithm of Data Codeword in Two-Dimensional PDF417 Bar Code

Background:: In the process of high-speed driving, the wheel hub is constantly subjected to the impact load from the ground. Therefore, it is important to estimate the fatigue life of the hub in the design and production process. Objective:: This paper introduces a method to study the fatigue life of car hub based on the road load collected from test site. Methods:: Based on interval analysis, the distribution characteristics of load spectrum are analyzed. The fatigue life estimation of one - dimensional and two - dimensional load spectra is compared by compiling load spectra. Results:: According to the S-N curve cluster and the one-dimensional program load spectrum, the estimated range fatigue life of the hub is 397,100 km to 529,700 km. For unsymmetrical cyclic loading, each level means and amplitude of load were obtained through the Goodman fatigue empirical formula, and then according to S-N curve clusters in the upper and lower curves and two-dimensional program load spectrum, estimates the fatigue life of wheel hub of the interval is 329900 km to 435200 km, than one-dimensional load spectrum fatigue life was reduced by 16.9% - 17.8%. Conclusion:: This paper lays a foundation for the prediction of fatigue life and the bench test of fatigue durability of auto parts subjected to complex and variable random loads. At the same time, the research method can also be used to estimate the fatigue life of other bearing parts or high-speed moving parts and assemblies.

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Accelerating laser processes with a smart two-dimensional polygon mirror scanner for ultra-fast beam deflection

Advanced Optical Technologies ◽

10.1515/aot-2021-0014 ◽

2021 ◽

Vol 0 (0) ◽

Author(s):

Florian Roessler ◽

André Streek

Keyword(s):

Energy Distribution ◽

Real Time ◽

Laser Processing ◽

High Speed ◽

Beam Deflection ◽

Two Dimensional ◽

Heat Accumulation ◽

Field Programmable ◽

Drill Holes ◽

Average Laser

Abstract In laser processing, the possible throughput is directly scaling with the available average laser power. To avoid unwanted thermal damage due to high pulse energy or heat accumulation during MHz-repetition rates, energy distribution over the workpiece is required. Polygon mirror scanners enable high deflection speeds and thus, a proper energy distribution within a short processing time. The requirements of laser micro processing with up to 10 kW average laser powers and high scan speeds up to 1000 m/s result in a 30 mm aperture two-dimensional polygon mirror scanner with a patented low-distortion mirror configuration. In combination with a field programmable gate array-based real-time logic, position-true high-accuracy laser switching is enabled for 2D, 2.5D, or 3D laser processing capable to drill holes in multi-pass ablation or engraving. A special developed real-time shifter module within the high-speed logic allows, in combination with external axis, the material processing on the fly and hence, processing of workpieces much larger than the scan field.

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An Efficient Match Search Approach Using Two-Dimensional Hash Function in Hardware-Based Dictionary Compression

Journal of Circuits System and Computers ◽

10.1142/s0218126619501068 ◽

2019 ◽

Vol 28 (06) ◽

pp. 1950106

Author(s):

Qian Dong ◽

Bing Li

Keyword(s):

Compression Ratio ◽

Hash Function ◽

High Speed ◽

Two Dimensional ◽

Time Data ◽

Search Result ◽

Compression Speed ◽

Real Time Data ◽

Real Time Data Processing ◽

Search Approach

The hardware-based dictionary compression is widely adopted for high speed requirement of real-time data processing. Hash function helps to manage large dictionary to improve compression ratio but is prone to collisions, so some phrases in match search result are not true matches. This paper presents a novel match search approach called dual chaining hash refining, which can improve the efficiency of match search. From the experimental results, our method showed obvious advantage in compression speed compared with other approach that utilizes single hash function described in the previous publications.

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