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Number of results: 6
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Abstract

The issue of maximizing penetration depth with concurrent retaining or enhancement of image resolution constitutes one of the time invariant challenges in ultrasound imaging. Concerns about potential and undesirable side effects set limits on the possibility of overcoming the frequency dependent attenuation effects by increasing peak acoustic amplitudes of the waves probing the tissue. To overcome this limitation a pulse compression technique employing 16 bits Complementary Golay Sequences (CGS) Code was implemented at 4 MHz. In comparison with other, earlier proposed, coded excitation schemes, such as chirp, pseudo-random chirp and Barker codes, the CGS allowed virtually side lobe free operation. Experimental data indicate that the quality — resolution, signal penetration and contrast dynamics — of CGS images is better than the one obtain for standard ultrasonography using short burst excitation.

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Authors and Affiliations

A. Nowicki
W. Secomski
I. Trots
J. Litniewski
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Abstract

This work describes a 4-bit Flash ADC with low power consumption. The performance metrics of a Flash ADC depend on the kind of comparator and encoder used. Hence openloop comparator and mux-based encoder are used to obtain improved performance. Simulation results show that the simulated design consumes 0.265mW of power in 90nm CMOS technology using cadence-virtuoso software. The circuit operates with an operating frequency of 100MHz and a supply voltage of 1V.
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Authors and Affiliations

D. S. Shylu Sam
1
P. Sam Paul
1
Diana Jeba Jingle
2
P. Mano Paul
3
Judith Samuel
1
J. Reshma
1
P. Sarah Sudeepa
1
G. Evangeline
1

  1. Karunya Institute of Technology & Sciences, Coimbatore, India
  2. Christ (Deemed to be University), Bangalore, India
  3. Alliance University, Bangalore, India
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Abstract

The article addresses the relation between the grammatical gender and the linguistic encoding of sex distinction (natural gender). Our goal is to problematize the category of gender as a multipart and multifunctional linguistic phenomenon operating in diverse dimensions of a language. The analysis of Italian and Polish languages illustrates that grammatical gender – whose main function is to signal syntactic relations between text constituents – and natural gender – whose main function is to encode information about the sex of a referent – are in principle autonomous and independent linguistic phenomena which are however strongly interrelated in a linguistic system through a morphological and syntactic interface.

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Authors and Affiliations

Agnieszka Latos
ORCID: ORCID
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Abstract

Dynamic angle measurement (DAM) plays an important role in precision machining, aerospace, military and artificial intelligence. Because of its advantages including high sensitivity, solid state and miniaturization, fibre-optic gyroscope (FOG) has great application prospects in the field of DAM. In this paper, we propose a dynamic angle metrology method based on FOG and a rotary table to evaluate the DAMaccuracy with FOG. The system synchronously collects data from the FOG and rotary table, and analyses the DAM accuracy of the FOG for different sway conditions compared with that of the angle obtained from the rotary table. An angle encoder in the rotary table provides absolute or incremental angular displacement output with angular displacement measurement accuracy of 10′′ (0:0028◦) and angular displacement repeat positioning accuracy of 3′′ (0:00083◦), and can be used as an angle reference. The experimental results show that the DAM accuracy of the FOG is better than 0:0028◦ obtained with the angular encoder, and the absolute DAM accuracy of the FOG is better than 0:0048◦ for given conditions. At the same time, for the multi-path signal synchronization problem in the metrology field, this paper proposes a signal delay measurement method combining test and algorithm procedures, which can control a delay within 25 μs.

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Authors and Affiliations

Lei Chen
Yilan Zhou
Dengwei Zhang
Xiaowu Shu
Cheng Liu
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Abstract

Optimization of encoding process in video compression is an important research problem, especially in the case of modern, sophisticated compression technologies. In this paper, we consider HEVC, for which a novel method for selection of the encoding modes is proposed. By the encoding modes we mean e.g. coding block structure, prediction types and motion vectors. The proposed selection is done basing on noise-reduced version of the input sequence, while the information about the video itself, e.g. transform coefficients, is coded basing on the unaltered input. The proposed method involves encoding of two versions of the input sequence. Further, we show realization proving that the complexity is only negligibly higher than complexity of a single encoding. The proposal has been implemented in HEVC reference software from MPEG and tested experimentally. The results show that the proposal provides up to 1.5% bitrate reduction while preserving the same quality of a decoded video.
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Authors and Affiliations

Olgierd Stankiewicz
Krzysztof Wegner
Damian Karwowski
Jakub Stankowski
Krzysztof Klimaszewski
Tomasz Grajek
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Abstract

The telemetry data are essential in evaluating the performance of aircraft and diagnosing its failures. This work combines the oversampling technology with the run-length encoding compression algorithm with an error factor to further enhance the compression performance of telemetry data in a multichannel acquisition system. Compression of telemetry data is carried out with the use of FPGAs. In the experiments there are used pulse signals and vibration signals. The proposed method is compared with two existing methods. The experimental results indicate that the compression ratio, precision, and distortion degree of the telemetry data are improved significantly compared with those obtained by the existing methods. The implementation and measurement of the proposed telemetry data compression method show its effectiveness when used in a high-precision high-capacity multichannel acquisition system.

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Authors and Affiliations

Xiaopu Shang
Yongfeng Ren
Guoyong Zheng
Kaiqun Wang

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