scholarly journals A Method for the Analysis of Interference from DME to ATCRBS in the Time Domain

Electronics ◽  
2019 ◽  
Vol 8 (4) ◽  
pp. 393 ◽  
Author(s):  
Guofeng Jiang ◽  
Yangyu Fan ◽  
Hongbo Yuan ◽  
Pengliang Yuan

Analysis of the coexistence of two or more types of equipment is increasingly important. However, at present studies on the analysis method in the time domain are scant. Therefore, the aim of this paper is to explore the characteristics of signals and relations between interfering and desired signals in the time domain. Based on the periodicity of a signal, this paper presents a Periodic Pulse Overlap Method (PPOM). Using PPOM to analyze the interference from Distance Measuring Equipment (DME) to Air Traffic Control Radar Beacon System (ATCRBS) in the time domain, we obtain almost the same result as that based on the Monte Carlo Method (MCM). Furthermore, we discover the measures to reduce or even avoid interference, such as changing the Pulse Recurrence Frequency (PRF), adjusting the difference of initial time, and switching the operating modes of the equipment.

2012 ◽  
Vol 2012 ◽  
pp. 1-7 ◽  
Author(s):  
Bing Li ◽  
Jing-song Hong

Two novel dual band-notched ultra-wideband (UWB) printed monopole antennas with simple structure and small size are presented. The size of both antennas is25×25×0.8 mm3. The bandwidth of one of the proposed antenna can be from 2.7 GHz to 36.8 GHz, except the bandwidth of 3.2–3.9 GHz for WiMAX applications and 5.14–5.94 GHz for WLAN applications. The bandwidth of the other is ranging for 2.7 to 41.1 GHz, except the bandwidth of 3.2–3.9 GHz for WiMAX applications and 4.8–5.9 GHz for WLAN applications. Bandwidths of the antennas are about 512% and 455% wider than those of conventional band-notched UWB antennas, respectively. In addition, the time-domain characteristics of the two antennas are investigated to show the difference between both antennas.


Energies ◽  
2020 ◽  
Vol 13 (11) ◽  
pp. 2759 ◽  
Author(s):  
Wojciech Uchman ◽  
Janusz Kotowicz ◽  
Leszek Remiorz

In this article, an investigation of a free-piston Stirling engine-based micro-cogeneration (μCHP) unit is presented. This work is a step towards making the system calculations more reliable, based on a data-driven model, which enables the time-domain simulation of the μCHP behavior. A laboratory setup was developed that allowed for the measurement of a micro-cogeneration unit during long-term operation with a variable thermal load. The maximum efficiency of electricity generation was equal to 13.2% and the highest overall efficiency was equal to 95.7%. A model of the analyzed μCHP system was developed and validated. The simulation model was based on the device’s characteristics that were obtained from the measurements; it enables time-domain calculations, taking into account the different operating modes of the device. The validation of the system showed satisfactory compliance of the model with the measurements: for the period modeled of 24 h, the error in the heat generation fluctuated in the range 0.31–4.50%, the error in the electricity generation was in the range 2.48–4.70%, the error in the natural gas consumption was in the range 0.26–4.59%, and the engine’s runtime error was in the range 0.14–8.58%. The modelling process is easily applicable to other energy systems for detailed analysis.


2014 ◽  
Vol 945-949 ◽  
pp. 1090-1093
Author(s):  
Hai Peng Zhang ◽  
Hong Wu Chen ◽  
Bin Hu ◽  
Cheng Tian

This paper simulated the unbalance vibration conditions by the vibration test platform, measuring some common characteristic parameters of unbalance vibration fault diagnosis. This paper chose the time-domain analysis method, processing the characteristic parameters of the test, so as to achieve the purpose of vibration diagnosis. Through a large number of experimental data, this paper verified the feasibility and the effectiveness of the proposed approach to the unbalance fault diagnosis. The method proposed in this paper not only can be applied to unbalance fault diagnosis, but also can be promoted to apply to the fault diagnosis of other rotating machinery.


2012 ◽  
Vol 479-481 ◽  
pp. 1186-1189
Author(s):  
Ping Liu ◽  
Hua Ma ◽  
Xue Wei Zhang ◽  
Xin Yu Sun ◽  
Fei Cao

The time domain wavenumber analysis method can directly delay and align signals before the superposition of signals in the time domain. In this paper, estimating the direction of wavefront propagation and the slowness for seismic signals which pass through the small-size dense seismic array is described in detail. The earthquake recorder sample adopted from US Geological Survey Parkfield Dense Seismograph Array (UPSAR array) of the U.S is used for analyzing. The results indicate that, the direction of wavefront propagation cannot be determined rashly only by the connecting line of the earthquake epicenter to the seismic array. The accuracy of the apparent velocity and the direction of wavefront propagation calculated using vertical seismic recorders is higher in West-East direction and in North-South direction.


Author(s):  
Yinglong Zhao ◽  
Lin He ◽  
Zhiqiang Lv ◽  
Yu Wang

Choosing the equipment with good shock-resistant performance and taking shock protection measures while designing the onboard settings, the safety of onboard settings can be assured when warships, especially submarine subjected to non-contact underwater explosion, that is, these means can be used to limit the rattlespace (i.e., the maximum displacement of the equipment relative to the base) and the peak acceleration experienced by the equipment. Using shock-resistant equipments is one of shock protection means. The shock-resistant performance of the shock-resistant equipments should be verified in the design phase of the equipments. The shock design analysis methods used before and now includes shock design number method (static g-method), dynamic analysis in the time domain and dynamic design analysis method (DDAM). The FEA (Finite Element Analysis) software, for example, MSC.NASTRAN®, can be used for shock design analysis of the shock-resistant equipments. MSC.NASTRAN are used for shock design analysis of floating raft vibration isolating equipment with dynamic analysis method in the time domain in this paper, and the analysis results are in agreement with the test results. The shock design analysis method used in this paper can be used to analyze the shock-resistant performance of onboard shock-resistant equipments.


1987 ◽  
Vol 109 (3) ◽  
pp. 244-248 ◽  
Author(s):  
H. Vogel ◽  
B. J. Natvig

The paper describes a highly effective method for computing the dynamics of the catenary-shaped suspension of flexible hose systems. The method accounts for a number of nonlinearities, it is 3-dimensional and it is performed in the time domain. The paper addresses the analysis method and demonstrates its effectiveness on a sample flexible riser analysis.


2020 ◽  
pp. 39-49
Author(s):  
A. Omelchuk ◽  
◽  
Y. Yarosh ◽  
V. Pryadko ◽  
O. Mashchenko ◽  
...  

The article investigates the parameters of setting up adjacent remote protections with remote start-up, taking into account the peculiarities of operating modes and operating conditions of partitioned branched distribution lines. The influence of parameters and modes of operation of such lines on the range of adjustment of settings on resistance and time of operation at the end of a zone of action and requirements to linearity of time characteristics that allows to define distances to a place of short circuit on operation time is defined. The results for setting up remote protections of partitioned lines with sources of distributed generation are obtained: the conditions for adjusting the protection settings for resistance to operation are determined taking into account the parameters of the partitioned lines and the limits of adjusting the settings for resistance to secondary values are determined. The conditions for adjusting the settings by the time of operation and the limits of the time of operation of protection for most lines are determined. For selective operation of protection at the selected settings on time of operation unambiguity of time characteristics at change of sizes of working currents of protection on condition of ten percent accuracy of work of protection on resistance of operation is provided. The conditions for ensuring the selective operation of adjacent protections in the selected range of settings by the time of operation, taking into account the ratio of resistances and the difference in the time of operation are determined. The initial time of protection protection is substantiated for debugging of protection on time of operation against operation of overvoltage limiters and against burnout of fusible insert of fuses of branches and unsoldering at short circuit directly behind the fuse. The use of modern microprocessor protection devices will ensure, on the one hand, the accuracy of the resistance, linear and unambiguous dependence of the operating time on the resistance of the short circuit at different levels of currents and voltages, etc., and on the other hand - ease of maintenance.


2021 ◽  
Vol 55 (1) ◽  
pp. 115-126
Author(s):  
Lifen Hu ◽  
Chen Yao ◽  
Wubin Li ◽  
Xiangyang Wang ◽  
Zhongyu Sun

AbstractThis study proposes a method for combining capsizing probability and flooding process to investigate the time-domain dead ship stability of a damaged ship. It focuses on a nonlinear righting lever GZ curve solution in the following aspects: one aspect subjects the influence of damaged tanks on a hull shape to the wind and wave, and the other aspect is based on a real-time calculation of the GZ curve. According to 1‐degree-of-freedom rolling equation, the damaged capsizing probability model is established through fourth-order Runge-Kutta algorithm and Monte Carlo simulation. Also, the model solution is applied on the basis of Visual Basic 6.0 language, and the results are compared with the NAPA platform. The most significant development in this study is combining time-domain flooding process and capsizing probability calculation. To verify the proposed methods, two damaged fishery bureau vessels are used as the sample ships. Results of time-domain capsizing probability under different loading conditions are compared, and the difference and its possible reasons are analyzed.


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