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Abstract

The problem of consolidation of soil has been widely investigated. The basic approach was given by Terzaghi who assumed soil of constant physical and mechanical parameters. In the case of peat consolidation, the permeability coefficient of soil and the elasticity modulus are functions of the settlement which is an important additional factor. The model proposed here assumes varying the elasticity and permeability coefficients. Moreover, the settlement is described by the so-called elementary curve which was approximated empirically based upon laboratory tests. The model allows to consider the case when the filtration in the peat body goes in horizontal direction. It happens so when the charging layer does not receive outgoing water from the pores. The model includes also the case when the load involving consolidation varies in time i.e. the charging layer grows up gradually. The model has been applied practically in several cases and it comes that there is a good agreement between calculated and measured settlement of the consolidated peat layer.

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Authors and Affiliations

Z. Meyer
R. Coufal
M. Kowalów
T. Szczygielski
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Abstract

This paper presents a method for assessing the degree of approaching the paper output of the Clausius-Rankine cycle to the Carnot cycle. The computations to illustrate its use were performed for parameters characteristic of the current state of development of condensing power plants as well as in accordance with predicted trends for their further enhancing. Moreover there are presented computations of energy dissipation in the machines and devices working in such a cycle.

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Authors and Affiliations

Henryk Łukowicz
Tadeusz Chmielniak
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Abstract

Many business offices around the world are organized as open plan offices. Therefore, studies about the acoustic comfort of the people who work in them have become increasingly important. The focus of this work is the acoustic evaluation of an open plan office combining several architectural characteristics and levels of ambient noise. This evaluation was performed through a computational model calibrated from a real office. The rate of spatial decay of sound pressure levels per distance doubling (DL2) and the speech transmission index (STI) were simulated for the acoustic evaluation of the office, allowing for the determination of the radius of distraction (rD). These parameters were simulated for 6 situations using different floor and ceiling covering materials and inserting or withdrawing screens between workstations. In addition, STI and rD were simulated under two conditions of ambient noise. The results indicated that the DL2 and rD are adequate acoustic parameters for the acoustic evaluation and improvement of an open plan office. The DL2 was strongly influenced by the presence or absence of screens between workstations and by the ceiling covering material. The rD was more sensitive to changes in ambient noise.

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Authors and Affiliations

Carolina Passero
Paulo Zannin
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Abstract

In a reality of global competition, companies have to minimize production costs and increase productivity in order to boost com-petitiveness. Facility layout design is one of the most important and frequently used efficiency improvement methods for reducing operational costs in a significant manner. Facility layout design deals with optimum location of facilities (workstation, machine, etc.) on the shop floor and optimum material flow between these objects. In this article, the objectives and procedure of layout design along with the calculation method for layout optimization are all introduced. The study is practice-oriented because the described case study shows how the layout of an assembly plant can be modified to form an ideal re-layout. The research is novel and innovative because the facility layout design and 4 lean methods (takt-time design, line balance, cellular design and one-piece flow) are all combined in order to improve efficiency more significantly, reduce costs and improve more key performance indicators. From the case study it can be concluded that the layout redesign and lean methods resulted in significant reduction of the following seven indicators: amount of total workflow, material handling cost, total travel distance of goods, space used for assembly, number of workers, labor cost of workers and the number of Kanban stops.

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Authors and Affiliations

G. Kovács
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Abstract

Lean has established itself as the primordial approach to obtain operational excellence. Its simple and intuitive techniques focus on reducing lead time through continuous improvement, involving all levels of employees in the organization. However, the rate of successful implementations has remained low. This paper contributes to the understanding of continuous improvement in a Lean context, by analyzing a database of almost 10.000 improvement actions, from 85 companies, covering the time frame 2010–2018. It discusses categories of actions, their impact and cost, as well as key characteristics of the companies. It proposes an objective criterion to identify “success” and “failure” in Lean implementation and tries to link these to operational results. It is probably the first time an analysis of this magnitude on the subject has been performed.

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Authors and Affiliations

Hendrik Van Landeghem
Dieter Claeys
Thomas Van Landeghem
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Abstract

The purpose of the paper is to present the author’s reflections on the origin and popularity

of various approaches to maintenance and improvement of production processes, their

terminological consistency, understanding, and practical application of their principles. The

author’s reflections are based on his observations made over his many years of activity as

a lecturer and consultant in the area of production engineering and management. It was

shown that there is a need to make scientists and practitioners aware of the relatively large

degree of freedom in defining the scope and way of application of strategies of continuous

improvement. The author’s proposal is to refer to all approaches to maintenance and improvement

of production processes with the title “Strategies of Efficient Action” and all

supporting methods as “Practices of Efficient Action”.

Considerations presented in the paper can be useful in more and more efficiently applying

the power of TQM, Six Sigma, Lean Manufacturing and other strategies of processes

maintenance and improvement in the daily activities of companies.

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Authors and Affiliations

Adam Hamrol
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Abstract

The material presents a real problem inherent in the management of computer systems, namely that of finding the appropriate system settings and thus being able to achieve the expected perfor- mance. The material also presents a prototype which aims to adapt the system in such a way as to achieve the objective, defined as the application efficiency. The prototype uses a resource-oriented mechanism that is built into the OS Workload Manager and is focused on a proposed goal-oriented subsystem based on fuzzy logic, managing resources to make the best use of them, and pursuing translation to the use of system resources, including nondeterministic technology-related factors such as duration of allocation and release of the resources, sharing the resources with the uncapped mode, and the errors of performance measurement.
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Authors and Affiliations

Maciej Młyński
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Abstract

The paper presents the technology and organization of the artistic cast production. On the basis of the actual cast production system, the

manufacturing process was shown, in particular sand–piece moulding, which is a very important process and a time-consuming part of the

entire manufacture of the casts. The current state of the production process as well as the organization of the work and production

technology were analysed with the use of methods and techniques of production improvement, the Lean Manufacturing concept and

computer systems. The results of the analysis and studies were shown with use of schemes and graphs of the layout of the production

resources, a flow chart of the production process, value stream mapping, and a costs table for the production and modernization of the

moulding stage. The work has shown that there are possibilities to improve the artistic cast production system. This improvement leads to

increased productivity, lower production costs of artistic casts and increased competitiveness of the foundry.

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Authors and Affiliations

R. Władysiak
T. Pacyniak
J. Trzoska
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Abstract

Six Sigma as the continuation of comprehensive quality management TQM is of interest to many enterprises. Unfortunately, not everybody successfully implements quality improvement projects using Six Sigma tools. This approach requires proper preparation in many areas of the company’s operation, including: organization of processes, establishing measures, employee engagement and creating conditions for continuous improvement. The goal of the article is to present on the case study the idea of using the organizational maturity model for production management to assess a readiness of organization to implement Six Sigma. The case study presents a company maturity level diagnosis and a successful project of quality and productivity improvement using the Six Sigma concept, confirming that the organization’s maturity model is the appropriate tool for assessing multi-faceted preparation for successful implementation of Six Sigma projects.
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Authors and Affiliations

Anna Kosieradzka
Olga Ciechańska
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Abstract

This study demonstrates application of Lean techniques to improve working process in

a sewing machine factory, focusing on the raw material picking process. The value stream

mapping and flow process chart techniques were utilized to identify the value added activities,

non-value activities and necessary but non-value added activities in the current

process. The ECRS (Eliminate, Combine, Rearrange and Simplify) in waste reduction was

subsequently applied to improve the working process by (i) adjusting the raw material picking

procedures and pre-packing raw material as per demand, (ii) adding symbols onto the

containers to reduce time spent in picking material based on visual control principle, and

(iii) developing and zoning storage area, identifying level location for each row and also

applying algorithms generated from a solver program and linear programming to appropriately

define the location of raw material storage. Improvement in the raw material picking

process was realized, cutting down six out of 11 procedures in material picking or by 55%,

reducing material picking time from 24 to 4 min or by 83%. The distance to handle material

in the warehouse can be shortened by 120 m per time or 2,400 m per day, equal to 86%

reduction. Lean techniques

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Authors and Affiliations

Kotcharat Srisuk
Korrakot Y. Tippayawong
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Abstract

Today’s agriculture is facing a range of challenges, the most important of which is the adjustment to the changing climate. In this context, water management is particularly vital. Droughts in Poland are becoming more and more frequent. That fact adds to the significance of irrigation and drainage systems.
This paper is an attempt at diagnosing the condition of (in 2016) and changes in (over the period of 2006–2016) irrigation and drainage systems in the Kujawsko-Pomorskie Voivodship (analysed by communes, until 2016 – according to Local Administrative Units – LAU level 2). The multidirectional analysis involves a comprehensive description of ameliorated lands, including the allocation of the EU funds dedicated for the support of flood protection and land improvement ventures.
It has been demonstrated that the present condition of land improvement does not reflect the needs of the agriculture in the studied area and that the changes implemented on the ongoing basis fail to make the situation better. In 2016, slightly over 40% of agricultural acreage was ameliorated, while the level at which land improvement needs would be satisfied approximated 70%. In over 1/5 of the ameliorated area, facilities needed reconstruction or modernisation. Drainage systems were in the majority, which indicates that the current needs, i.e. water scarcity, are not addressed.
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Authors and Affiliations

Roman Rudnicki
1
ORCID: ORCID
Łukasz Wiśniewski
1
ORCID: ORCID

  1. Nicolaus Copernicus University in Toruń, Faculty of Earth Sciences and Spatial Management, ul. Gagarina 11, 87-100 Toruń, Poland
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Abstract

Workpiece surface roughness measurement based on traditional machine vision technology faces numerous problems such as complex index design, poor robustness of the lighting environment, and slow detection speed, which make it unsuitable for industrial production. To address these problems, this paper proposes an improved YOLOv5 method for milling surface roughness detection. This method can automatically extract image features and possesses higher robustness in lighting environments and faster detection speed. We have effectively improved the detection accuracy of the model for workpieces located at different positions by introducing Coordinate Attention (CA). The experimental results demonstrate that this study’s improved model achieves accurate surface roughness detection for moving workpieces in an environment with light intensity ranging from 592 to 1060 lux. The average precision of the model on the test set reaches 97.3%, and the detection speed reaches 36 frames per second.
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Authors and Affiliations

Xiao Lv
1
Huaian Yi
1
Runji Fang
1
Shuhua Ai
1
Enhui Lu
2

  1. School of Mechanical and Control Engineering, Guilin University of Technology, Guilin, 541006,People’s Republic of China
  2. School of Mechanical Engineering, Yangzhou University, Yangzhou, 225009, People’s Republic of China
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Abstract

PID controllers are crucial for industrial control because of their simple structure and good robustness. In order to further improve the accuracy of PID controllers, this paper proposes an improved sparrow search algorithm (ISSA) to prevent the problem of the algorithm being prone to falling into the local optimum at the late stage of iteration. Based on the standard sparrow search algorithm, the position update formula and the step size control parameter are optimized to help quickly jump out of the local, and to obtain the optimal solution in the whole domain. Finally, to verify the accuracy and stability of the improved algorithm, nine standard test functions are first simulated. Then, the PID parameter optimization tests are finished with the chilled water and battery charging systems, where the lifting load and applying perturbation are carried out. Both the simulation and test results show that ISSA improves the convergence speed and accuracy, and performs better in terms of stability.
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Authors and Affiliations

Mingfeng Zhang
1
Chuntian Xu
1
ORCID: ORCID
Deying Xu
1
Guoqiang Ma
1
Han Han
2
Xu Zong
3

  1. School of Mechanical Engineering and Automation, University of Science and Technology Liaoning, Anshan, Liaoning, China
  2. College of Science – Computer Science, University of Arizona, Tucson, Arizona, USA
  3. Angang Steel Co. LTD, Anshan Iron & Steel, Anshan, Liaoning, China
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Abstract

In the present study, the evolution of different failure mechanisms in carbon fiber reinforced polymer composites is being investigated using acoustic emission technique, unsupervised clustering technique and improved b-value analysis. The experimental part involved the realization of tensile tests of different materials, namely samples with [0/90]2S uniaxial layer configuration and [0/90]2S twill fabric samples. Both types of tests were monitored using one wideband acoustic emission sensor, while the tensile tests of twill fabric samples were additionally supplemented with resonant acoustic emission sensor to perform a comparative analysis between datasets from resonant/wideband acoustic emission sensor. The comparative study itself was preceded by the failure mechanisms characterization process, which has been performed on the tensile test dataset of [0/90]2S layer configuration with the contribution of clustering technique. The subsequent analysis of the twill fabric resonant/wideband acoustic emission sensor datasets included the improved b-value technique, which relates the magnitude of fracture with the slope of the amplitude distribution. The presented results, especially in terms of the improved b-value technique applied to individual clusters, show enhanced ability to assess in more detail the actual structural integrity depending on the applied load.
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Authors and Affiliations

M. Šofer
1
ORCID: ORCID
P. Kwiatoń
2
ORCID: ORCID
P. Pavlíček
1
ORCID: ORCID

  1. VŠB-Technical University of Ostrava, Faculty of Mechanical Engineering, Department of Applied Mechanics, 17. listopadu 15/2127, 708 33 Ostrava-Poruba, Czech Republic
  2. Czestochowa University of Technology, Faculty of Mechanical Engineering and Computer Science, Department of Mechanics and Machine Design Fundamentals, 73 Dąbrowskiego Str., 42-201 Częstochowa, Poland
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Abstract

The aim of the article is to present an exemplary system for recording and analyzing quality costs and to demonstrate that it is helpful in planning and assessing the effectiveness of continuous improvement processes at the operational and strategic level. Various approaches to defining quality costs are described, followed by indicators for assessing effectiveness and tools to collect data on the values of individual groups of quality costs and compare them with financial indicators. The practical part presents a case study on the quality cost accounting system in a medical company and the possibility of using quality cost accounting to plan and evaluate continuous improvement processes and make managerial decisions.
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Authors and Affiliations

Ilona Herzog
Marta Grabowska
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Abstract

Drilled displacement columns, constructed in the form of unreinforced or reinforced concrete elements, are currently a very commonly used method of improving soft subsoil, creating an alternative to more expensive pile foundations. A frequently used solution for improving soft soils of road or railway embankments is to design a regular pattern of columns of relatively small diameter. Columns along the perimeter of the improved area are reinforced with rigid steel profiles, while the internal ones are made as concrete elements. Column heads are usually covered with a load transfer platform (layer of compacted granular fill) which is additionally reinforced with geosynthetics.
The application of soil improvement with displacement columns is not always successful. It is due to the errors and shortcomings occurring at the design stage, including simplifications in modelling, to construction faults, which may include insufficient experience of contractors and/or improper supervision.
Referring to the real object that failed, the article provides the results of numerical parametric analyses taking into account the influence of the key design parameters such as: the stiffness of the load transfer layers, the amount and stiffness of the geosynthetic reinforcement as well as the column spacing. The article presents comparisons of numerical results obtained with the finite element analyses for various approaches to geometry modelling (axisymmetric, 2D and 3D). The simulations indicate that the use of the axisymmetric model of a single column in routine design may lead to the deformations exceeding the serviceability limit states.
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Authors and Affiliations

Waldemar Szajna
1
ORCID: ORCID
Liudmyla Bondareva
2
ORCID: ORCID
Bartosz Szatanik
3
ORCID: ORCID

  1. University of Zielona Góra, Institute of Civil Engineering, Prof. Zygmunta Szafrana 1 Street, 65-516 Zielona Góra, Poland and TPA – Technical Research Institute, Parzniewska 8 Street, 05-800 Pruszków, Poland
  2. Kyiv National University of Construction and Architecture, 31 Povitroflotski avenue, 03037, Kyiv, Ukraine and TPA – Technical Research Institute, Parzniewska 8 Street, 05-800 Pruszków, Poland
  3. TPA – Technical Research Institute, Parzniewska 8 Street, 05-800 Pruszków, Poland and MSc., Eng., TPA – Technical Research Institute, Parzniewska 8 Street, 05-800 Pruszków, Poland
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Abstract

The radial distribution system is a rugged system, it is also the most commonly used system, which suffers by loss and low voltage at the end bus. This loss can be reduced by the use of a capacitor in the system, which injects reactive current and also improves the voltage magnitude in the buses. The real power loss in the distribution line is the I2R loss which depends on the current and resistance. The connection of the capacitor in the bus reduces the reactive current and losses. The loss reduction is equal to the increase in generation, necessary for the electric power provided by firms. For consumers, the quality of power supply depends on the voltage magnitude level, which is also considered and hence the objective of the problem becomes the multi objective of loss minimization and the minimization of voltage deviation. In this paper, the optimal location and size of the capacitor is found using a new computational intelligent algorithm called Flower Pollination Algorithm (FPA). To calculate the power flow and losses in the system, novel data structure load flow is introduced. In this, each bus is considered as a node with bus associated data. Links between the nodes are distribution lines and their own resistance and reactance. To validate the developed FPA solutions standard test cases, IEEE 33 and IEEE 69 radial distribution systems are considered.

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Authors and Affiliations

V. Tamilselvan
T. Jayabarathi
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Abstract

Lean manufacturing [LM], quality management system and environmental management system are clear initiatives with a goal of improving effectiveness and efficiencies of organizations. Many organisations tackle lean philosophy, ISO standards individually but this kind of attempt do not focus on the synergy and the advantage from the potential collaboration. This paper aims to present the possibility of integration Lean Management concept with ISO management systems – Quality Management System [QMS] ISO 9001and Environmental Management System [EMS] ISO 14001 already implemented in the enterprises. The integration of these three concepts can be obtain due to improvement of main KPI’s defined in the organization. Based on critical research literature and participant observation presented as a case study (one of the author of the paper works as a consultant and is being implemented Lean Manufacturing concept in different organization since ten years) authors defined concept of integration of EMS and QMS (already implemented in the organization) with chosen Lean Management tools. Concept has been developed based on literature analysis and experience of the authors. Results and summary from concept implementation has been described in last chapter of the paper.
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Authors and Affiliations

Marek Wirkus
Anna Chmielarz
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Abstract

World Class Manufacturing system consists of ten technical and ten managerial pillars.

These, impacting directly and indirectly on each other, generate the flow of internal processes. Two of the mentioned pillars, Early Product Management (EPM) and Cost Deployment

(CD) play a special role in the system, because they create a future strategic management

of a company influencing design engineering, manufacturing and economy [1, 2]. Referring

to the author’s previous publications on Early Product Management methodology [3, 4], the

role of Cost Deployment pillar in the new product launch remains an important issue. Additionally, there is a noticeable lack of publications in this specific field of the WCM system.

Therefore, a proper understanding of the relationship between these two technical pillars

is the basis for effective project management for the implementation of new products. In

this article, the correlation between EPM and CD will be highlighted whereas some critical

remarks will be indicated. The main part of the article will describe: the current approach to

project management according to the standards set by the WCM system and recommended

improvements originated from EPM and CD pillars. The quality scientific methods used in

this article are based on a case study of internal processes in an international plant specializing in agriculture machinery production and include elements of direct observation and

theoretical analysis and synthesis. This paper refers to the presented issues in practical terms

on the example of the methodology of managing of new launch product projects in terms of

cost management. The purpose of this paper is to draw attention to the problem of the cost

factor generated during the design phase and early implementation of the new product into

production, which will enable effective cost management of new implementation projects.

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Authors and Affiliations

Andrzej Mróz
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Abstract

The main purpose of this article is to present an author’s methodology of production levelling

and to show the impact of levelling on the time during which the product passes

through the process and on staff performance. The article presents the analysis of literature

concerning the method of improving the production process, especially taking production

levelling into consideration. The authors focussed on the definition and methodologies of

production levelling. A diagram of interrelations showing determinants and efficiency measures

of production levelling as well as an author’s production levelling methodology have

been presented. An example of the implementation of production levelling in one of the departments

of a company manufacturing surgical instruments has also been shown. Analysis

of the current state, stages of implementation and end effects have been presented. Attention

was focussed on the time during which the product passes through the process and on staff

performance.

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Authors and Affiliations

Paulina Rewers
Mariusz Bożek
Wojciech Kulus
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Abstract

There is a general agreement that remembering depends not only on the memory processes as such but rather that encoding, storage and retrieval are under the constant influence of the overarching, metacognitive processes. Moreover, many interventions designed to improve memory refer in fact to metacognition. Most attempts to integrate the very different theoretical and experimental approaches in this domain focus on encoding, whereas there is relatively little integration of approaches that focus on retrieval. Therefore, we reviewed the studies that used new ideas to improve memory retrieval due to a “metacognitive intervention”. We concluded that whereas single experimental manipulations were not likely to increase metacognitive ability, more extensive interventions were. We proposed possible theoretical perspectives, namely the Source Monitoring Framework, as a means to integrate the two, so far separate, ways of thinking about the role of metacognition in retrieval: the model of strategic regulation of memory, and the research on appraisals in autobiographical memory. We identified venues for future research which could address, among other issues, integration of these perspectives.

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Authors and Affiliations

Ewa Skopicz-Radkiewicz
Agnieszka Niedzwienska
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Abstract

Commutation reactance is an important component in the voltage-source converter- based high-voltage direct current (VSC–HVDC) transmission system. Due to its connection to the converter, when there is a fault occurring on the valve-side bushing of a converter transformer, the nonlinearity operation of the converter complicates the characteristics of current flowing through commutation reactance, which may lead to maloperation of its overcurrent protection. It is of great significance to study the performance of commutation reactance overcurrent protection under this fault condition and propose corresponding improvement measures to ensure the safe and stable operation of AC and DC systems. In the VSC–HVDC system with the pseudo-bipolar structure of a three-phase two-level voltage source converter, the valve has six working periods in a power frequency cycle, and each period is divided into five working states. According to the difference between the fault phase and non-fault phase of the conductive bridge arms at the time of fault occurrence, these five working states are merged into two categories. On this basis, various faults of the valve-side bushing of a converter transformer are analyzed, and the conclusion is drawn that the asymmetric fault of valve-side bushing can lead to the maloperation of the commutation reactance overcurrent protection. Based on the characteristics that the current flowing through the commutation reactance after the asymmetric fault of the valve-side bushing contains decaying aperiodic components in addition to the fundamental frequency wave, a scheme to prevent the maloperation of commutation reactance overcurrent protection is proposed, which uses the unequal of two half cycle integral values with different starting points to realize the blocking of commutation reactance overcurrent protection, and it makes up the deficiency of existing protection in this aspect. Finally, this paper builds a VSC–HVDC system simulation model in the PSCAD/EMTDC platform to verify the effectiveness of the scheme.
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Authors and Affiliations

Yanxia Zhang
1
Guanghao Dong
1
ORCID: ORCID
Le Wei
1
Jinting Ma
1
Shanshan Du
1

  1. School of Electrical and Information Engineering, Tianjin University, No. 92 Weijin Road, Nankai District, Tianjin, China
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Abstract

A transformer is an important part of power transmission and transformation equipment. Once a fault occurs, it may cause a large-scale power outage. The safety of the transformer is related to the safe and stable operation of the power system. Aiming at the problem that the diagnosis result of transformer fault diagnosis method is not ideal and the model is unstable, a transformer fault diagnosis model based on improved particle swarm optimization online sequence extreme learning machine (IPSO-OS-ELM) algorithm is proposed. The improved particle swarmoptimization algorithm is applied to the transformer fault diagnosis model based on the OS-ELM, and the problems of randomly selecting parameters in the hidden layer of the OS-ELM and its network output not stable enough, are solved by optimization. Finally, the effectiveness of the improved fault diagnosis model in improving the accuracy is verified by simulation experiments.

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Authors and Affiliations

Yuancheng Li
Longqiang Ma
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Abstract

The evolution of microstructured optical fibers with hexagonal array (H-MOFs) of air-holes rooted in the background of undoped silica has led to the realization of an ideal host for encouraging and technologically entitled optical properties. We focus to explore the divergence of radiation into free space from the end-facet of solid-core H-MOFs by using the improved theoretical model. Also, we investigated the wavelength dependence of beam divergence angle for principal core mode of H-MOFs under step-index fiber approximation (SIFA). Experimental results have been included for comparison.

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Authors and Affiliations

D.K. Sharma
S.M. Tripathi

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