Bulletin of the Polish Academy of Sciences-Technical Sciences最新文献_第8页

Theory II: Deep learning and optimization 理论二:深度学习和优化

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.2018.125925

T. Poggio, Q. Liao

{"title":"Theory II: Deep learning and optimization","authors":"T. Poggio, Q. Liao","doi":"10.24425/BPAS.2018.125925","DOIUrl":"https://doi.org/10.24425/BPAS.2018.125925","url":null,"abstract":"Bull. Pol. Ac.: Tech. 66(6) 2018 Abstract. The landscape of the empirical risk of overparametrized deep convolutional neural networks (DCNNs) is characterized with a mix of theory and experiments. In part A we show the existence of a large number of global minimizers with zero empirical error (modulo inconsistent equations). The argument which relies on the use of Bezout theorem is rigorous when the RELUs are replaced by a polynomial nonlinearity. We show with simulations that the corresponding polynomial network is indistinguishable from the RELU network. According to Bezout theorem, the global minimizers are degenerate unlike the local minima which in general should be non-degenerate. Further we experimentally analyzed and visualized the landscape of empirical risk of DCNNs on CIFAR-10 dataset. Based on above theoretical and experimental observations, we propose a simple model of the landscape of empirical risk. In part B, we characterize the optimization properties of stochastic gradient descent applied to deep networks. The main claim here consists of theoretical and experimental evidence for the following property of SGD: SGD concentrates in probability – like the classical Langevin equation – on large volume, ”flat” minima, selecting with high probability degenerate minimizers which are typically global minimizers.","PeriodicalId":55299,"journal":{"name":"Bulletin of the Polish Academy of Sciences-Technical Sciences","volume":"9 1","pages":""},"PeriodicalIF":1.2,"publicationDate":"2023-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81102459","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: 8

Road vehicle sequencing problem in a railroad intermodal terminal – simulation research 铁路多式联运码头道路车辆排序问题的仿真研究

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.2020.134643

M. Jacyna, R. Jachimowski, E. Szczepański, M. Izdebski

{"title":"Road vehicle sequencing problem in a railroad intermodal terminal – simulation research","authors":"M. Jacyna, R. Jachimowski, E. Szczepański, M. Izdebski","doi":"10.24425/BPASTS.2020.134643","DOIUrl":"https://doi.org/10.24425/BPASTS.2020.134643","url":null,"abstract":"The paper presents the issue of container handling processes at a railroad intermodal terminal. The main purpose of this paper is the assessment of the handling equipment utilization and the associated energy consumption. The authors analyze how the road vehicle availability at the moment specified in the containers loading schedule influences the total handling equipment operation time as well as the necessary number of handling equipment. It is assumed that vehicles planned for loading of import containers may be late for loading, which causes some interruptions in the loading schedule. Such interruptions are identified with the necessity to handle the next container for which the road vehicle is already waiting, which influences the handling equipment utilization and, finally, energy consumption. The general mathematical model of the problem developed in the FlexSim simulation software was presented. Based on the simulation research, it pointed out that proper road vehicles loading sequencing can significantly reduce handling equipment operation time, and thus energy consumption, costs, and CO2 emissions. The literature analysis presented in the paper indicates that most of the research in the field of intermodal transport is focused on operations optimization in container ports. There are differences between two types of intermodal terminals in operation procedures and rules. That is why the authors decided to undertake the problem of road vehicle sequencing including their random availability and its influence on handling device operation time, which has not been considered in the literature so far.","PeriodicalId":55299,"journal":{"name":"Bulletin of the Polish Academy of Sciences-Technical Sciences","volume":"85 1","pages":""},"PeriodicalIF":1.2,"publicationDate":"2023-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75844581","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: 10

Stationary supercapacitor energy storage operation algorithm based on neural network learning system 基于神经网络学习系统的固定式超级电容器储能运行算法

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.2020.134176

W. Jefimowski, A. Nikitenko, Z. Drążek, M. Wieczorek

{"title":"Stationary supercapacitor energy storage operation algorithm based on neural network learning system","authors":"W. Jefimowski, A. Nikitenko, Z. Drążek, M. Wieczorek","doi":"10.24425/BPASTS.2020.134176","DOIUrl":"https://doi.org/10.24425/BPASTS.2020.134176","url":null,"abstract":"The paper proposes to apply an algorithm for predicting the minimum level of the state of charge (SoC) of stationary supercapacitor energy storage system operating in a DC traction substation, and for changing it over time. This is done to insure maximum energy recovery for trains while braking. The model of a supercapacitor energy storage system, its algorithms of operation and prediction of the minimum state of charge are described in detail; the main formulae, graphs and results of simulation are also provided. It is proposed to divide the SoC curve into equal periods of time during which the minimum states of charge remain constant. To predict the SoC level for the subsequent period, the learning algorithm based on the neural network could be used. Then, the minimum SoC could be based on two basic types of data: the first one is the time profile of the energy storage load during the previous period with the constant minimum SoC retained, while the second one relies on the trains’ locations and speed values in the previous period. It is proved that the use of variable minimum SoC ensures an increase of the energy volume recovered by approximately 10%. Optimum architecture and activation function of the neural network are also found.","PeriodicalId":55299,"journal":{"name":"Bulletin of the Polish Academy of Sciences-Technical Sciences","volume":"1 1","pages":""},"PeriodicalIF":1.2,"publicationDate":"2023-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76072366","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

Static load test curve analysis based on soil field investigations 基于土壤现场调查的静载试验曲线分析

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.2019.128607

P. Siemaszko, Z. Meyer

引用次数: 9

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":"20 1","pages":""},"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

Influence of contact gaps on the conditions of vehicles supply and wear and tear of catenary wires in a 3 kV DC traction system 3kv直流牵引系统接触间隙对车辆供电条件及接触网导线磨损的影响

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.2020.133373

T. Maciołek, M. Lewandowski, A. Szeląg, M. Steczek

引用次数: 2

Stator winding fault diagnosis of induction motor operating under the field-oriented control with convolutional neural networks 基于卷积神经网络的定向磁场控制异步电动机定子绕组故障诊断

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.2020.134660

M. Skowron, M. Wolkiewicz, G. Tarchała

引用次数: 6

Application of extended Kalman filter for estimation of periodic disturbance and velocity ripple reduction in PMSM drive 扩展卡尔曼滤波在永磁同步电机周期扰动估计和速度纹波抑制中的应用

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.2020.134649

Ł. Niewiara, T. Tarczewski, L. Grzesiak

引用次数: 5

Energy-based spectrum sensing with copulas for cognitive radios 基于能量的频谱感知与认知无线电的copula

4区工程技术

Bulletin of the Polish Academy of Sciences-Technical Sciences Pub Date : 2023-11-06 DOI: 10.24425/bpasts.2020.134177

F.Y. Ilgin

引用次数: 5

Current harmonic controller in multiple reference frames for series active power filter integrated with 18-pulse diode rectifier 18脉冲二极管整流器串联有源滤波器多参考系电流谐波控制器

4区工程技术

Bulletin of the Polish Academy of Sciences-Technical Sciences Pub Date : 2023-11-06 DOI: 10.24425/bpas.2018.125336

W. Śleszyński, A. Cichowski, P. Mysiak

引用次数: 6