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Wigner transform approach to dynamic-variable partially coherent laser beam characterization 动态变量部分相干激光束表征的Wigner变换方法
IF 1.2 4区 工程技术
Bulletin of the Polish Academy of Sciences-Technical Sciences Pub Date : 2023-11-06 DOI: 10.24425/BPASTS.2020.131840
J. Jabczynski, P. Gontar, Ł. Gorajek
{"title":"Wigner transform approach to dynamic-variable partially coherent laser beam characterization","authors":"J. Jabczynski, P. Gontar, Ł. Gorajek","doi":"10.24425/BPASTS.2020.131840","DOIUrl":"https://doi.org/10.24425/BPASTS.2020.131840","url":null,"abstract":"1) Background: the modeling, characterization, transformation and propagation of high-power CW laser beams in optical (including fiberoptic) trains and in the atmosphere have become hot topics in laser science and engineering in the past few years. Single-mode output is mandatory for high-power CW laser applications in the military field. Moreover, an unstationary, dynamic operation regime is typical. Recognized devices and procedures for laser-beam diagnostics could not be directly applied because of dynamic behavior and untypical non-Gaussian profiles. 2) Methods: the Wigner transform approach was proposed to characterize dynamically variable high-power CW laser beams with significant deterministic aberrations. Wavefront-sensing measurements by means of the Shack-Hartmann method and decomposition into an orthogonal Zernike basis were applied. 3) Results: deterministic aberration as a result of unstationary thermal-optic effects depending on the averaged power of the laser output was found. Beam quality determined via the Wigner approach was changed in the same way as the measurements of the beam diameter in the far field. 4) Conclusions: such an aberration component seems to be the main factor causing degradation in beam quality and in brightness of high-power CW laser beams.","PeriodicalId":55299,"journal":{"name":"Bulletin of the Polish Academy of Sciences-Technical Sciences","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2023-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87021575","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 3
Center of circles intersection, a new defuzzification method for fuzzy numbers 圆心相交，一种新的模糊数去模糊化方法
IF 1.2 4区 工程技术
Bulletin of the Polish Academy of Sciences-Technical Sciences Pub Date : 2023-11-06 DOI: 10.24425/BPASTS.2020.131850
H. Zarzycki, W. Dobrosielski, Ł. Apiecionek, T. Vince
{"title":"Center of circles intersection, a new defuzzification method for fuzzy numbers","authors":"H. Zarzycki, W. Dobrosielski, Ł. Apiecionek, T. Vince","doi":"10.24425/BPASTS.2020.131850","DOIUrl":"https://doi.org/10.24425/BPASTS.2020.131850","url":null,"abstract":"The article introduces a new proposal of a defuzzif ication method, which can be implemented in fuzzy controllers. The f irst chapter refers to the origin of fuzzy sets. Next, a modern development based on this theory is presented in the form of ordered fuzzy numbers (OFN). The most important characteristics of ordered fuzzy numbers are also presented. In the following chapter, details about the defuzzif ication process are given as part of the fuzzy controller model. Then a new method of defuzzif ication is presented. The method is named center of circles intersection (CCI). The authors compare this method with a similar geometric solution: triangular expanding (TE) and geometric mean (GM). Also, the results are compared with other methods such as center of gravity (COG), f irst of maxima (FOM) and last of maxima (LOM). The analysis shows that the proposed solution works correctly and provides results for traditional fuzzy numbers as well as directed fuzzy numbers. The last chapter contains a summary, in which more detailed conclusions are provided and further directions of research are indicated.","PeriodicalId":55299,"journal":{"name":"Bulletin of the Polish Academy of Sciences-Technical Sciences","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2023-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88314421","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 3
Sensorless five-phase induction motor drive with third harmonic injection and inverter output filter 无传感器五相感应电机驱动与三次谐波注入和逆变器输出滤波器
IF 1.2 4区 工程技术
Bulletin of the Polish Academy of Sciences-Technical Sciences Pub Date : 2023-11-06 DOI: 10.24425/BPASTS.2020.133369
P. Strankowski, J. Guzinski, M. Morawiec, A. Lewicki, F. Wilczyński
{"title":"Sensorless five-phase induction motor drive with third harmonic injection and inverter output filter","authors":"P. Strankowski, J. Guzinski, M. Morawiec, A. Lewicki, F. Wilczyński","doi":"10.24425/BPASTS.2020.133369","DOIUrl":"https://doi.org/10.24425/BPASTS.2020.133369","url":null,"abstract":"The paper presents a sensorless control approach for a five-phase induction motor drive with third harmonic injection and inverter output filter. In the case of the third harmonic injection being utilised in the control, the physical machine has to be divided into two virtual machines that are controlled separately and independently. The control system structure is presented in conjunction with speed and rotor flux observers that are required for a speed sensorless implementation of the drive. The last section is dedicated to experimental results of the drive system in sensorless operation, and the uninterrupted drive operation for two open-phase faults.","PeriodicalId":55299,"journal":{"name":"Bulletin of the Polish Academy of Sciences-Technical Sciences","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2023-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90221538","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 3
The pointwise completeness and the pointwise degeneracy of fractional descriptor discrete-time linear systems 分数阶广义离散线性系统的点完备性和点退化性
IF 1.2 4区 工程技术
Bulletin of the Polish Academy of Sciences-Technical Sciences Pub Date : 2023-11-06 DOI: 10.24425/BPASTS.2019.130891
T. Kaczorek
{"title":"The pointwise completeness and the pointwise degeneracy of fractional descriptor discrete-time linear systems","authors":"T. Kaczorek","doi":"10.24425/BPASTS.2019.130891","DOIUrl":"https://doi.org/10.24425/BPASTS.2019.130891","url":null,"abstract":"The Drazin inverse of matrices is applied to analysis of the pointwise completeness and of the pointwise degeneracy of the fractional descriptor linear discrete-time systems. Necessary and sufficient conditions for the pointwise completeness and the pointwise degeneracy of the fractional descriptor linear discrete-time systems are established. It is shown that every fractional descriptor linear discrete-time systems is not pointwise complete and it is pointwise degenerated in one step (for i = 1).","PeriodicalId":55299,"journal":{"name":"Bulletin of the Polish Academy of Sciences-Technical Sciences","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2023-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90508115","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 2
Missing-data imputation using wearable sensors in heart rate variability 在心率变异性中使用可穿戴传感器的缺失数据输入
IF 1.2 4区 工程技术
Bulletin of the Polish Academy of Sciences-Technical Sciences Pub Date : 2023-11-06 DOI: 10.24425/BPASTS.2020.133118
A. Tlija, K. Wegrzyn-Wolska, D. Istrate
{"title":"Missing-data imputation using wearable sensors in heart rate variability","authors":"A. Tlija, K. Wegrzyn-Wolska, D. Istrate","doi":"10.24425/BPASTS.2020.133118","DOIUrl":"https://doi.org/10.24425/BPASTS.2020.133118","url":null,"abstract":"The objective of this work is to set up a methodology that considers missing data from a connected heartbeat sensor in order to propose a good replacement methodology in the context of heart rate variability (HRV) computation. The framework is a research project, which aims to build a system that can measure stress and other factors influencing the onset and development of heart disease. The research encompasses studying existing methods, and improving them by use of experimental data from case study that describe the participant’s everyday life. We conduct a study to modelize stress from the HRV signal, which is extracted from a heart rate monitor belt connected to a smart watch. This paper describes data recording procedure and data imputation methodology. Missing data is a topic that has been discussed by several authors. The manuscript explains why we choose spline interpolation for data values imputation. We implement a random suppression data procedure and simulate removed data. After that, we implement several algorithms and choose the best one for our case study based on the mean square error.","PeriodicalId":55299,"journal":{"name":"Bulletin of the Polish Academy of Sciences-Technical Sciences","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2023-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79621227","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 2
Super-resolution reconstruction of face images based on pre-amplification non-negative restricted neighborhood embedding 基于预放大非负约束邻域嵌入的人脸图像超分辨率重建
IF 1.2 4区 工程技术
Bulletin of the Polish Academy of Sciences-Technical Sciences Pub Date : 2023-11-06 DOI: 10.24425/bpas.2018.125937
Xin Yang, D. Liu, Dake Zhou, S. Fei
{"title":"Super-resolution reconstruction of face images based on pre-amplification non-negative restricted neighborhood embedding","authors":"Xin Yang, D. Liu, Dake Zhou, S. Fei","doi":"10.24425/bpas.2018.125937","DOIUrl":"https://doi.org/10.24425/bpas.2018.125937","url":null,"abstract":"Bull. Pol. Ac.: Tech. 66(6) 2018 Abstract. The traditional super-resolution (SR) reconstruction algorithm based on neighborhood embedding preserves the local geometric structure of image block manifold to reconstruct high-resolution (HR) manifold. However, when the magnification is large, the low resolution (LR) image is seriously degraded and most of the information is lost after down-sampling. The neighborhood relation of the LR manifold can not reflect the inherent data structure. In order to solve the problem effectively, we propose a face image SR algorithm based on pre-amplification non-negative restricted neighborhood embedding. In the training phase, the LR image is pre-amplified so that there are more similar manifold structures between the HR and LR resolution images. The constraints of the reconstructed coefficients are loosened and the HR image blocks are iteratively updated to obtain the reconstructed weights. The experimental results show that the proposed method has a better reconstruction effect compared with some traditional learning algorithms.","PeriodicalId":55299,"journal":{"name":"Bulletin of the Polish Academy of Sciences-Technical Sciences","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2023-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90616611","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 3
On evaluation of influence coefficients for edge and intermediate boundary elements in 3D problems involving strong field concentrations 强场集中三维问题中边缘和中间边界元影响系数的评价
IF 1.2 4区 工程技术
Bulletin of the Polish Academy of Sciences-Technical Sciences Pub Date : 2023-11-06 DOI: 10.24425/BPAS.2019.125435
L. Rybarska-Rusinek
{"title":"On evaluation of influence coefficients for edge and intermediate boundary elements in 3D problems involving strong field concentrations","authors":"L. Rybarska-Rusinek","doi":"10.24425/BPAS.2019.125435","DOIUrl":"https://doi.org/10.24425/BPAS.2019.125435","url":null,"abstract":"The paper presents a tool for accurate evaluation of high field concentrations near singular lines, such as contours of cracks, notches and grains intersections, in 3D problems solved the BEM. Two types of boundary elements, accounting for singularities, are considered: (i) edge elements, which adjoin a singular line, and (ii) intermediate elements, which while not adjoining the line, are still under strong influence of the singularity. An efficient method to evaluate the influence coefficients and the field intensity factors is suggested for the both types of the elements. The method avoids time expensive numerical evaluation of singular and hypersingular integrals over the element surface by reduction to 1D integrals. The method being general, its details are explained by considering a representative examples for elasticity problems for a piecewise homogeneous medium with cracks, inclusions and pores. Numerical examples for plane elements illustrate the exposition. The method can be extended for curvilinear elements.","PeriodicalId":55299,"journal":{"name":"Bulletin of the Polish Academy of Sciences-Technical Sciences","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2023-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90467031","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 1
Application of X-ray tomography to assess fatigue structural changes in asphalt mixtures 应用x射线断层扫描评估沥青混合料的疲劳结构变化
IF 1.2 4区 工程技术
Bulletin of the Polish Academy of Sciences-Technical Sciences Pub Date : 2023-11-06 DOI: 10.24425/BPAS.2019.128604
P. Mackiewicz, A. Szydło
{"title":"Application of X-ray tomography to assess fatigue structural changes in asphalt mixtures","authors":"P. Mackiewicz, A. Szydło","doi":"10.24425/BPAS.2019.128604","DOIUrl":"https://doi.org/10.24425/BPAS.2019.128604","url":null,"abstract":"The article presents an analysis of the change in air voids in asphalt mixtures subjected to fatigue tests at three temperatures of 0°C, 10°C and 25°C. The X-ray computerized tomography imaging method, XCT, was used to identify the air voids in the samples. The research allowed to determine changes in the content of air voids in subsequent fatigue cycles in the sample area. The relationship between air voids volume and the stiffness modulus value was also determined during fatigue for three temperatures. The largest changes were found in samples with notches at 0°C. The analysis of the change in the content of air voids showed that the micro-cracking nucleation processes develop with the number of fatigue cycles. Using the numerical model finite element method we determined the distribution and change in fatigue damage in the extreme areas of the sample during various stages of fatigue. We found clear relationship between the damage and the increased content of air voids.","PeriodicalId":55299,"journal":{"name":"Bulletin of the Polish Academy of Sciences-Technical Sciences","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2023-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87210147","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 2
Analytical calculations of surges caused by direct lightning strike to underground intrusion detection system 直接雷击对地下入侵探测系统浪涌的分析计算
4区 工程技术
Bulletin of the Polish Academy of Sciences-Technical Sciences Pub Date : 2023-11-06 DOI: 10.24425/bpas.2019.128118
K. Aniserowicz
{"title":"Analytical calculations of surges caused by direct lightning strike to underground intrusion detection system","authors":"K. Aniserowicz","doi":"10.24425/bpas.2019.128118","DOIUrl":"https://doi.org/10.24425/bpas.2019.128118","url":null,"abstract":"The paper presents an analysis of overvoltages caused by a direct lightning strike in intrusion detection system equipped with underground radiating cable sensors. Waveforms of currents and voltages in the system components are calculated using analytical formulas basing on a transmission-line model in the frequency domain. The time-domain waveforms are computed using the inverse fast Fourier transform (IFFT). Three network configurations of the intrusion detection system are analyzed.","PeriodicalId":55299,"journal":{"name":"Bulletin of the Polish Academy of Sciences-Technical Sciences","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135636164","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 4
Finite control set MPC of LCL-filtered grid-connected power converter operating under grid distortions 电网畸变下lcl滤波并网电源变换器的有限控制集MPC
4区 工程技术
Bulletin of the Polish Academy of Sciences-Technical Sciences Pub Date : 2023-11-06 DOI: 10.24425/bpasts.2020.134655
{"title":"Finite control set MPC of LCL-filtered grid-connected power converter operating under grid distortions","authors":"","doi":"10.24425/bpasts.2020.134655","DOIUrl":"https://doi.org/10.24425/bpasts.2020.134655","url":null,"abstract":"Most of the basic control methods of the grid-connected converter (GCC) are defined to work with a sine wave grid voltage. In that case if the grid voltage is distorted by higher harmonics, the grid current may be distorted too, which, in consequence, may increase the value of the THD of the grid voltage. The paper deals with an improved finite control set model predictive control (FCS-MPC) method of an LCL-filtered GCC operating under distorted grid conditions. The proposed method utilizes supplementary grid current feedback to calculate the reference converter current. The introduced signal allows to effectively improve the operation when the grid is subject to harmonic distortion. The paper shows a simulation analysis of the proposed control scheme operating with and without additional feedback under grid distortions. To validate the practical feasibility of the proposed method an algorithm was implemented on a 32-bit microcontroller STM32F7 with a floating point unit to control a 10 kW GCC. The laboratory test setup provided experimental results showing properties of the introduced control scheme.","PeriodicalId":55299,"journal":{"name":"Bulletin of the Polish Academy of Sciences-Technical Sciences","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135636167","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 5
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