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Abstrakt

This paper presents the bases of a new method of monitoring technical condition of turbomachine blades during their operation. The method utilizes diagnostic models such as a quotient of amplitude amplification and a phase shift of diagnostic signal y(t) which is a result of blade operation as well as a signal x(t) of blade environment while a blade tip approaches a sensor, amplitude amplification and phase shift of these signals while the blade tip moves away from the sensor. The adopted diagnostic models indirectly take into account the existing environment of a blade, represented by the signal x(t), without the need to measure it. Thus, the model is sensitive to the changes in technical condition of blades and practically intensive to a change in environment. The suggested method may prove very important in diagnostics of rotor blades during turbomachines operation (compressors, turbines etc.).

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Autorzy i Afiliacje

Paweł Lindstedt
Rafał Grądzki

Abstrakt

Structures and characteristics ofwideband small-size phase shiftersmade with the use of single parallel stubs are presented in this paper. The stubs can be short-circuited or open-circuited on termination. Such devices arewell known, but are primarily used as components of filters ormatching circuits. The novelty, then, comes from the establishment of simple, but helpful formulae, which enable to describe the insertion phase shift and differential phase shift of a line with short and open stubs connected in parallel. These equations can be very useful for designing complex microwave multi-ports. The results of simulations and measurements of the devices, which were designed and made, are shown herein. It was also proved that the presented devices have several usable operating frequency sub-bands, and that the differential phase shift values in the higher sub-bands are greater than those in the lower operating frequency ranges. Thanks to this, the described phase shifters can be used in more than one frequency sub-band. It was stated that in the conditions under analysis, larger phase shifts can be achieved using open-circuited stubs rather than short-circuited stubs. However, the phase shifters with shorted parallel stubs can operate in a wider frequency band.

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Autorzy i Afiliacje

Adam Rutkowski

Abstrakt

In this paper, we design and analyse the Circuit for Grover’s Quantum Search Algorithm on 2, 3 and 4-qubit systems, in terms of number of gates, representation of state vectors and measurement probability for the state vectors. We designed, examined and simulated the quantum circuit on IBM Q platform using Quantum Programming Studio. We present the theoretical implementation of the search algorithm on different qubit systems. We observe that our circuit design for 2 and 4-qubit systems are precise and do not introduce any error while experiencing a small error to our design of 3-qubit quantum system.
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Autorzy i Afiliacje

Diana Jingle
1
Shylu Sam
2
Mano Paul
3
Ananth Jude
4
Daniel Selvaraj
4

  1. Christ University, Bangalore, India
  2. Karunya Institute of Technology and Sciences, Coimbatore, India
  3. Alliance University, Bangalore, India
  4. Sri Krishna College of Engineering and Technology, Coimbatore, India

Abstrakt

This paper deals with the phase-shift fault analysis of stream cipher Grain v1. We assume that the attacker is able to desynchronize the linear and nonlinear registers of the cipher during the keystream generation phase by either forcing one of the registers to clock one more time, while the other register is not clocked, or by preventing one of the registers from clocking, while the other register is clocked. Using this technique, we are able to obtain the full inner state of the cipher in reasonable time (under 12 hours on a single PC) by using 150 bits of unfaulted keystream, 600 bits of faulted keystreams and by correctly guessing 28 bits of the linear register.
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Autorzy i Afiliacje

Viliam Hromada
Pethő Tibor

Abstrakt

In order to meet the operation requirements of the beam supply with multiworking conditions, multi-modes and high efficiency, a dual-mode hybrid output control method combining phase-shifting and pulse-width dual-mode modulation technology with secondary side series-parallel operation is proposed. In this paper, the structure and working mode of the new dual full-bridge topology are firstly analyzed. Secondly, the main circuit parameters are designed according to the power performance indicators, and the losses under two control modes of phase shift and pulse width are calculated. Finally, comparing the losses of these two control methods, and combining the series-parallel operation mode of the secondary side of the transformer, a dual-mode switching control method of the beam supply is designed. In order to verify the rationality of the dual-mode mixed output control method, a principle prototype with a rated capacity of 2 kW, a rated voltage of 1 800 V and a switching frequency of 50 kHz was used for verification. Experiments show the effectiveness and superiority of the dual-mode hybrid output control method.
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Autorzy i Afiliacje

Changzu An
1
ORCID: ORCID
Hongxia Lu
2

  1. CCCC Ruitong Road & Bridge Maintenance Technology Co. Ltd., China
  2. Xi‘an Railway Vocational & Technical Institute, China

Abstrakt

Due to the skin effect of eddy currents, the depth of cracks which can be detected by the traditional eddy current probe is very limited. In order to improve the ability of eddy current probes to inspect deep cracks in metal thick-walled structures, a new eddy current probe using an excitation system with phase shifted fields was proposed. Its feasibility for detecting deep cracks was verified by simulation and experiments. The results showed that the penetration depth of eddy currents in austenitic stainless steel is effectively enhanced by using the new probe.

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Autorzy i Afiliacje

Meixian Wu
Dongli Zhang
Chuanglong Wang

Abstrakt

Phase shift interferometry (PSI) derived from interference technique as greater surface characterization technique based on the interference information recorded during a controlled phase shift. This research shows the development of micro/nano structures using phase shift interferometry. (PSI) is the process of developing the complex pattern structure using variable phase angle between two or more beams aligned to obtain functional aperiodic arrays. We have designed and modelled the PSI and simulated through MATLAB in 2D and 3D pattern structures. The PSI was performed in two process analysis. First, without PSI referring normal interference technique. Second, with PSI referring position of laser beams in quadrant-based alignment. The obtained results show the minimum feature structure was measured as 12 nm. This feature size developed under phase shift interferometry (PSI) produces minimum feature size compared to the existing interferometry technique. This study gives the promising increased fabrication area could develop large area arrays structures.
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Autorzy i Afiliacje

Pearly Princess. J
1
A. Alfred Kirubaraj
1
S. Christina Sophia
1
S. Senith
1
S.R. Jino Ramson
2

  1. Karunya Institute of Technology and Sciences, Karunya Nagar, India
  2. VIT Bhopal University, Bhopal, India

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