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Number of results: 28
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Abstract

The aim of this paper is the methodology of measurements executed in a radio link for the realization of radiolocation services in radiocommunication networks, particularly in cellular networks. The main results of the measurements obtained in the physical layer of the universal mobile telecommunications system (UMTS) are introduced. A new method for the utilization of the multipath propagation phenomenon to improve the estimation of the distance between the mobile station (MS) and the base station (BS) is outlined. This method significantly increases the quality of location services in systems which use a radio interface with direct sequence code division multiple access (DS CDMA).

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Authors and Affiliations

Jacek Stefanski
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Abstract

The article outlines how to use the convergence of collections to determine the position of a mobile device based on the WiFi radio signal strength with the use of fuzzy sets. The main aim is the development of the method for indoor position determination based on existing WiFi network infrastructure indoors. The approach is based on the WiFi radio infrastructure existing inside the buildings and requires operating mobile devices such as smartphones or tablets. An SQL database engine is also necessary as a widespread data interface. The SQL approach is not limited to the determination of the position but also to the creation of maps in which the system dening the position of the mobile device will operate. In addition, implementation issues are presented along with the distribution of the burden of performing calculations and the benets of such an approach for determining the location. The authors describe how to decompose the task of determining the position in a client-server architecture.

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Authors and Affiliations

Michał Socha
Wojciech Górka
Iwona Kostorz
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Abstract

The optimal decision regarding the place of production is an essential, sometimes determining factor of its effectiveness. The main drawback in substantiating the optimal location of production is the lack of a system approach to accounting in the analysis of potential sales markets. Orientation, when justifying the optimal location of production, only to some particular sales market (and orientation to specific sales markets is necessary both in terms of taking into account the costs of moving the benefit from the place of production to the places of consumption, and in terms of production capacity, since it depends unit cost of production) is erroneous because it does not take into account many other competitive options. The article develops a system approach to rationale optimal locations and production capacity, based on a comparison of combinations of locally optimal places, the total production capacity of which is equal to the total (system) demand. The variant of combinations of locally optimal places with minimal total costs is systemically optimal. The result of solving the problem will be information about 4 parameters of the production of benefit: “where?” (in what places), “how much?” (in each of these places), “how?” (with what technology in each of these places), “for whom?” (sales markets for each of these places). The system approach proposed in the article to rationale the optimal location of the production of a single benefit can be adapted to a more complex situation, when the optimal location of the production of several benefits is justified at the same time. Further research is promising in the direction of a clearer determination of the boundaries of the space of possible location of production, as well as in the direction of studying the possibility of aggregating potential sales markets.
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Authors and Affiliations

Jerzy Stadnicki
1
Andrii Terebukh
2

  1. Faculty of Management and Computer Modelling, Kielce University of Technology, Poland
  2. Department of Tourism, Lviv Polytechnic National University, Ukraine
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Abstract

Trade is one of the key factors determining sustainable city development and its surroundings. City development is a result of provision of goods and services to city inhabitants, and residents of its surrounding areas. Retail trade in Poland belongs to economy sectors in which the processes of market changes were started the earliest. Discount stores that apply the strategy of low prices in the in the process of market conquering are currently one of the most dynamically developing selling formats. These shopping facilities are located in many Polish cities, including small towns and rural areas. The aim of the article is to show the scale of investments in new discount shops in small towns and rural areas in Poland in 2012–2015. Research focused at devoted to this field is important from the point of view of choosing the location of new investments related to discount chains and of the small towns and rural areas development strategies. Identification of consequences of discount chains operations in chosen rural areas and small towns can impact the verification of the policy adopted by local authorities in relation to spatial planning and forming the functional structure of the space. It will result in more conscious (rational) decisions in terms of localizing new discounts, which will reduce the number of local conflicts related to location of such facilities.

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Authors and Affiliations

Małgorzata Twardzik
Katarzyna Bilińska-Reformat
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Abstract

The noise of motor vehicles is one of the most important problems as regards to pollution on main roads. However, this unpleasant characteristic could be used to determine vehicle speed by external observers. Building on this idea, the present study investigates the capabilities of a microphone array system to identify the position and velocity of a vehicle travelling on a previously established route. Such linear microphone array has been formed by a reduced number of microphones working at medium frequencies as compared to industrial microphone arrays built for location purposes, and operates with a processing algorithm that ultimately identifies the noise source location and reduces the error in velocity estimation
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Authors and Affiliations

Ramón Peral-Orts
Emilio Velasco-Sánchez
Nuria Campillo-Davó
Héctor Campello-Vicente
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Abstract

Seed-borne diseases of wheat such as Fusarium head blight (FHB), a fungal disease caused by several species of Fusarium, results in reduced yield and seed quality. The aim of this study was to identify the Fusarium species, the effect of Fusarium-infected seeds on germination and vigor indices and to determine the location of Fusarium spp. in seeds, as well as to investigate the pathogenicity and variability of aggressiveness of the isolates obtained from pre-basic seeds wheat fields in Iran. According to morphological and molecular characters, the species F. graminearum, F. culmorum, F. avenaceum and F. poae were identified. Among the isolates, F. graminearum was the predominant species with the highest frequency and relative density of 92.9% and 70.9%, respectively. We observed that germination and vigor indices were decreased due to increased Fusarium-infected seeds. Results indicated significant differences among cultivars and seed-borne Fusarium levels. While a higher infection level of Fusarium spp. most commonly occurred in the seed coat, only F. graminearum was observed in embryos. Our study about pathogenicity showed that 77.3% of the Fusarium spp. isolates were not pathogenic and 22.7% isolates of Fusarium spp. were pathogenic or weakly pathogenic. Our results indicated that variability in aggressiveness among isolates of a species and positive correlation may be determined by pathogenicity tests. This is the first time the location of Fusarium spp. in seeds has been identified. It is also the first time that Fusarium-infected seeds in pre-basic seeds wheat fields of Iran have been evaluated.

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Authors and Affiliations

Farshid Hassani
Leila Zare
Nima Khaledi
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Abstract

This paper presents the comparison of filtering methods – median filtration, moving average Kalman filtration and filtration based on a distance difference to determine the most accurate arm length for circular motion, as a model of wind turbine propellers movement. The experiments have been performed with the UWB technology system containing four anchors and a tag attached to 90cm arm that was rotated with speed up to 15.5 rad/s (as a linear speed of 50km/h). The trilateration concept based on the signal latency has been described in order to determinate the position of an object on circular trajectory. The main objective is the circle plane rotation (parallel and perpendicular) with respect to the anchors plane reference system. All research tasks have been performed for various cases of motion schemes in order to get the filtration method for object in motion under best accuracy goal. Filtration methods have been applied on one of two stages of the positioning algorithm: (1) on raw data got from the single anchor-tag (before trilateration); (2) on the position obtained from four anchors and tag (after trilateration). It has been proven that the appropriate filtering allows for higher location accuracy. Moreover, location capabilities with the use of UWB technology – shows prospective use of positioning of objects without access to other positioning forms (ex. GPS) in many aspects of life such as currently developing renewable, green energy sources like wind turbines where the circular motion plays an important role, and precise positioning of propellers is a key element in monitoring the work of the whole wind turbine.

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Authors and Affiliations

Damian Grzechca
Krzysztof Hanzel
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Abstract

This paper concerns measurement procedures on an emotion monitoring stand designed for tracking human emotions in the Human-Computer Interaction with physiological characteristics. The paper addresses the key problem of physiological measurements being disturbed by a motion typical for human-computer interaction such as keyboard typing or mouse movements. An original experiment is described, that aimed at practical evaluation of measurement procedures performed at the emotion monitoring stand constructed at GUT. Different locations of sensors were considered and evaluated for suitability and measurement precision in the Human- Computer Interaction monitoring. Alternative locations (ear lobes and forearms) for skin conductance, blood volume pulse and temperature sensors were proposed and verified. Alternative locations proved correlation with traditional locations as well as lower sensitiveness to movements like typing or mouse moving, therefore they can make a better solution for monitoring the Human-Computer Interaction.

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Authors and Affiliations

Agnieszka Landowska
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Abstract

In deep mines, since the broken surrounding rocks & high-stress level of a roadway being near a coal seam, the creep characteristics of surrounding rocks should be considered as the main influencing factor in the selection for the roadway’s location of the lower coal seam. Both VI15 and VI16-17 coal seams of the Pingdingshan No. 4 Coal Mine, in China, Henan province, are close coal seams with a depth of around 900 m. According to the traditional formula calculation results, when the lower coal seam roadway is staggered 10 m to the upper coal seam goaf, the roadway pressure behaviour is significant, and the support becomes difficult. In this paper, the properties of surrounding rock were tested and the influence of lower coal seam on the stress state of surrounding rock is analysed by numerical simulation, and systematic analysis on the stress and creep characteristics of the surrounding rock of the mining roadway and its effects on the deformation is performed. The results demonstrated that the roadway’s locations in the lower coal seam can be initially divided into three zones: the zone with accelerated creep, the transition creep zone and the insignificant creep zone. The authors believed that the roadway layout in an insignificant creep zone can achieve a better supporting effect. Based on the geological conditions of the roadway 23070 of the VI16-17 coal seam of the Pingdingshan No. 4 Coal Mine, combined with the above analysis, a reasonable location of roadway (internal offset of 30 m) was determined using numerical simulation method. The reliability of the research results is verified by field measurement. The above results can provide a reference for selecting the roadway’s location under similar conditions.
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Bibliography


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[4] Y . Zhang, C.L. Zhang, C.C. Wei, Y.D. Liu, S.Q. Zhang, J.J. Zhao,. The Study on Roadway Layout in Coordination of Mining Coal Seams Base on Failure of Floor Strata. Trans Tech Publications 889-890, 1362-1374 (2014). DOI: https://doi.org/10.4028/www.scientific.net/AMR.889-890.1362
[5] W. Yang, C.Y. Liu, B.X. Huang, Y. Yang, Determination on Reasonable Malposition of Combined Mining in Close- Distance Coal Seams. Journal of Mining & Safety Engineering 29 (1), 101-105 (2012). DOI: https://doi.org/10.3969/j.issn.1673-3363.2012.01.018
[6] G . Yan, Y.Q. Hu, X. Song, Y.P. Fu, Z. Liu, Y. Yang, Theory and Physical Simulation of Conventional Staggered Distance during Combined Mining of Ultra-close Thin Coal Seam Group. Chinese Journal of Rock Mechanics & Engineering 28 (03), 591-597 (2009). DOI: https://doi.org/10.3321/j.issn:1000-6915.2009.03.019
[7] Y . Yong, S.H. Tu, L.N. Lu, X.T. Ma, G. Jie, Unconventional staggered distance simultaneous mining theory in extremely close and thin coal seams and its application. Procedia Earth & Planetary Science 1 (1), 288-293 (2009). DOI: https://doi.org/10.1016/j.proeps.2009.09.046
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Authors and Affiliations

Xufeng Wang
1
ORCID: ORCID
Jiyao Wang
1
ORCID: ORCID
Xuyang Chen
1
ORCID: ORCID
Zechao Chen
1
ORCID: ORCID

  1. Jiangsu Engineering Laboratory of Mine Earthquake Monitoring and Prevention, School of Mines, China University of Mining and Technology, Xuzhou 221116, China
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Abstract

Ecology and life characteristics of overwintering larvae of the European corn borer (Ostrinia nubilalis Hbn.) (Lep.: Crambidea) are partly unexplored due to their hidden lifestyle. In plant protection research the best way to study these phenomena is to apply less used, non-destructive, in vivo methods. The objective of our CT survey was to examine the factors influencing the location of the overwintering O. nubilalis larvae in maize stalks. The findings obtained by CT-analysis can be used for monitoring the presence and location of O. nubilalis larvae in the stalk, as well as both their displacement and movement. Our results showed that both the location and the distance from the brace root of O. nubilalis larvae were significantly influenced by the sampling time, the number of larvae per plant, the stalk diameter and finally the prevailing temperature. The location of the larvae situated nearest to the brace roots (first larvae) was significantly lower in stalks containing several larvae, than those where only a single larva was found in the stalk. The thickness of stalks was related to the simultaneous presence of more larvae, and to the ground level position of the first larvae. These overwintering larvae were located closer to the brace root (and to the soil), possibly because of having moved downwards inside the stalk, where the temperature is slightly milder than in the upper part of the stalk.

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Authors and Affiliations

Keszthelyi Sándor
Gabriella Holló
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Abstract

The goal of multi-criteria decision making (MCDM) is to select the most appropriate of the alternatives by evaluating many conflicting criteria together. MCDM methods are widely available in the literature and have been used in various energy problems. The key problems studied in electrical power systems in recent years have included voltage instability and voltage collapse. Different flexible alternating current transmission systems (FACTS) equipment has been used for this purpose for decades, increasing voltage stability while enhancing system efficiency, reliability and quality of supply, and offering environmental benefits. Finding the best locations for these devices in terms of voltage stability in actual electrical networks poses a serious problem. Many criteria should be considered when determining the most suitable location for the controller. The aim of this paper is to provide a comparative analysis of MCDM techniques to be used for optimal location of a static VAR compensator (SVC) device in terms of voltage stability. The ideal location can be determined by means of sorting according to priority criteria. The proposed approach was carried out using the Power System Analysis Toolbox (PSAT) in MATLAB in the IEEE 14-bus test system. Using ten different MCDM methods, the most appropriate locations were compared among themselves and a single ranking list was obtained, integrated with the Borda count method, which is a data fusion technique. The application results showed that the methods used are consistent among themselves. It was revealed that the integrated model was an appropriate method that could be used for optimal location selection, providing reliable and satisfactory results to power system planners.
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Authors and Affiliations

Faruk Aydin
1
ORCID: ORCID
Bilal Gümüş
2
ORCID: ORCID

  1. Department of Electrical and Electronics Engineering, Faculty of Technology, Marmara University, İstanbul 34722, Turkey
  2. Department of Electrical and Electronics Engineering, Faculty of Engineering, Dicle University, Diyarbakır 21680, Turkey
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Abstract

Daylight character in a space can be defined as the manner in which daylight permeates and is dispersed in that space. The architectural elements related to daylighting under investigation in this study were rooted in Iranian-Isfahani heritage, considered traditional Iranian architecture (from the 16th to early 20th century). The establishment of a classification system for daylighting systems holds significant utility. This study aims to delineate the architectural components present in Isfahani-style structures that facilitate the ingress of daylight, thereby enhancing the indoors.
The methodology employed in this research relies on subjective observation and photographic documentation. Based on the findings of this study, architectural daylighting elements can be organized into four distinct categories: Controllers, Scatterers, Filterers, and Modifiers. This classification system delineated these categories based on the observed order in their complexity (in terms of both quantity and quality of daylight treatment), function (pertaining to lighting, view-out, or shading), material characteristics (including transparency, roughness, and brightness), and their impact on daylighting (such as distribution, colour rendition, and intensity). Daylight Controllers encompassed elements like the hurno (skylight), the ravaq, the sabat, and the tabesh-band/sarsayeh/kharakpoush (shading devices), while daylight Scatterers encompassed the shabak, the rozan, the pachang (windows and doors), and the muqarnas (an ornamental feature of skylight). Daylight Filterers, representing more advanced elements when compared to the previous two categories, included the goljam (windows) and the jam-khaneh (skylights). The most intricate daylight manipulation elements were the daylight Modifiers, exemplified by the orosi (windows) and the roshandan (skylight)
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Authors and Affiliations

Mosleh Ahmadi
1
ORCID: ORCID
Natalia Sokół
1
ORCID: ORCID
Joanna Francuzik
1
ORCID: ORCID
Justyna Martyniuk-Pęczek
1
ORCID: ORCID

  1. Gdańsk University of Technology Faculty of Architecture and Urban Planning
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Abstract

The main purpose of the article is to try to substantiate the advisability of classification

of benefits according to the criterion of factors of the location of their production and to

develop a matrix for such a classification. Morphological analysis is used as the main study

method. The existence of four groups and a number of subgroups of benefits is established,

in the location of production of which one pair of factors dominates: from the “production

of benefits” side and from the “place” side. The basics of the classification of benefits are

developed, the location of production of which should take into account several pairs of

factors. The result is a matrix for performing the classification of benefits by factors of the

location of production, the filling of which will improve the quality and speed up decisionmaking on the choice of optimal places for the production of benefits. This study, in addition

to being important for the theory of benefits and the theory of the spatial organization of

the economy, has significant practical and social consequences, since it makes an important

step in improving the justification for the location of production of benefits.

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Authors and Affiliations

Jerzy Stadnicki
Andrii Terebukh
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Abstract

Designed by the architect Louis I. Kahn, the Phillips Exeter Academy Library is renowned mostly for the quality of its inner spaces. Particularly, the image of the building's central void with its large circular openings giving an insight onto the bookshelves has almost become an archetype of the library. Following the building's design process, however, we will learn how many tangible factors participated in the actual shaping of its architecture. The uniqueness of this project relies not only on embodying the idea of the library as institution, but also on the compromises the architect took as well as on the building's adjustment to its environmental setting.
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Authors and Affiliations

Marta Pieczara
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Abstract

This paper presents an improved approach for locating and identifying faults for UHV overhead Transmission line by using GA-ANFIS. The proposed method uses one end data to identify the fault location. The ANFIS can be viewed either as a Fuzzy system, neural network or fuzzy neural network FNN. The integration with neural technology enhances fuzzy logic system on learning capabilities are proposed to analyze the UHV system under different fault conditions. The performance variation of two controllers in finding fault location is analyzed. This paper analyses various faults under different conditions in an UHV using Matlab/simulink. The proposed method is evaluated under different fault conditions such as fault inception angle, fault resistance and fault distance. Simulation results confirm that the proposed method can be used as an efficient for accurate fault location on the transmission line.

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Authors and Affiliations

G. Banu
S. Suja
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Abstract

This article presents combined approach to analog electronic circuits testing by means of evolutionary methods (genetic algorithms) and using some aspects of information theory utilisation and wavelet transformation. Purpose is to find optimal excitation signal, which maximises probability of fault detection and location. This paper focuses on most difficult case where very few (usually only input and output) nodes of integrated circuit under test are available.

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Authors and Affiliations

Ł. Chruszczyk
D. Grzechca
J. Rutkowski
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Abstract

The Act of July 5, 2018 on Facilitating of Preparation and Implementation of Housing and Accompanying Investments allows such investments irrespective of the existence of a local development plan or determination of use of land in the local development plan. In other words, the abovementioned investments may be implemented on land with a completely different designation according to the local development plan, as for example the mining of minerals. The location of the investment is decided by a resolution of the municipal council. If the planned location is to be situated within the boundaries of documented mineral deposits and the so-called „mining areas”, it needs, among others, to be agreed with the appropriate geological administration authority. Not taking a position within 21 days is considered as a consent. With reference to the deposits not covered by mining licenses, the Act does not indicate the premises that should be taken into consideration while providing such consent. There is a concern that this may lead to the development of the land in a way that will cause the subsequent extraction of the mineral impossible.

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Authors and Affiliations

Aleksander Lipiński
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Abstract

A geo-radar method is used for detection of underground installations with the use of electromagnetic waves. Results of investigations of installations depend on physical properties of soil media, which properties result in suppression, reflection and refraction of electromagnetic waves. Three parameters, electric permittivity E, magnetic permittivity μ and the medium conductivity a play the major role in establishing electric features of a material medium. Suppression of the electromagnetic wave has the basic influence on detection of underground installations with the use of the geo-radar, and, in particular, on the depth range of the method. Relation between designing parameters of the geo-radar equipment and its depth range is determined by the basic equation of the geo-radar method. Solution of the basic equation of the geo-radar method for the needs of detection of underground installations requires performing experimental measurements. Measurements of the maximum depth of detection of underground installations with the use of the geo-radar have been performed in media of known physical properties, i.e. in the air, water and water solutions of NaCl of various concentrations. Two steel pipes of diameters of</!= 0.03 m and O. l Om were the objects for testing. Measurements were performed with the use of antennae of frequencies of !OOO MHz and 200 MHz. The results obtained in the form of echograms were analysed in order to determine the maximum distances for which the tested pipes were recorded. Experiments allowed to state that the maximum measurements of the depth range of the geo-radar equipment is rapidly decreased with the decrease of the background's specific resistance below 50 Qm. An increase of the soil resistance above 500 Q m results in slight increase of the depth range of measurements. Tests and analyses performed concerned homogenous media, i.e. metal installations, for which the electromagnetic wave is fully reflected.
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Authors and Affiliations

Wiesław Nawrocki
Zbigniew Piasek
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Abstract

Among the FACTS device, the distributed power flow controller (DPFC) is a superior device. This can be evaluated after eliminating the dc capacitor between shunt and series convertors of the unified power flow controller (UPFC) and placing a number of low rating single phase type distributed series convertors in the line instant of using single large rating three phase series convertors as in the UPFC. The power flow through this dc capacitor as in the UPFC now takes place through the transmission line at a third harmonic frequency in the DPFC. The DPFC uses the D-FACTS that allows the replacement of a large three-phase converter as in the UPFC by several small-size series convertors present in the DPFC. The redundancy of several series convertors increases the system’s reliability of the power system. Also, there is no requirement for high voltage isolation as series convertors of the DPFC are hanging as well as single-phase types. Consequently, the DPFC system has a lower cost than the UPFC system. In this paper, the equivalent ABCD parameters of the latest FACTSdeviceDPFChave been formulated with the help of an equivalent circuit model of the DPFC at the fundamental frequency component. Further, the optimal location in the transmission line and maximum efficiency of the DPFC along with Thyristor Controlled Series Compensator (TCSC), Static Synchronous Shunt Compensator (STATCOM) and UPFC FACTS devices have been investigated using an iteration program developed in MATLAB under steady-state conditions. The results obtained depict that the DPFC when placed slightly off-center at 0.33 fraction distance from the sending end comes up with higher performance. Whereas, when the TCSC, STATCOM and UPFC are placed at 0.16, 0.2815, 0.32 fraction distances from sending end respectively give their best performance.
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Bibliography

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Authors and Affiliations

Santosh Kumar Gupta
Jayant Mani Tripathi
Mrinal Ranjan
Ravi Kumar Gupta
Dheeraj Kumar Gupta
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Abstract

This paper aims to address the problems of inaccurate location and large computation in hybrid transmission line traveling wave detection methods. In this paper, a new fault location method based on empirical Fourier decomposition (EFD) and the Teager energy operator (TEO) is proposed. Firstly, the combination of EFD and the TEO is used to detect the time difference between the arrival of the initial traveling wave of the fault at the two measurement ends of the hybrid line. Then, when the fault occurs at the midpoint of each line segment and at the connection point of the hybrid line, the time difference between the arrival of the fault traveling wave at the two measurement ends of the line is calculated according to the line parameters. By comparing the obtained time differences, it is determined whether the fault occurs in the first or second half of the line. Finally, the fault distance is calculated using the double-ended traveling wave method according to the fault section. The model was built on PSCAD and the proposed algorithm was simulated on MATLAB platform. The results demonstrate that the proposed method achieves an average fault location accuracy of 98.88% by adjusting transition resistances and fault distances and comparing with other location methods. After validation, the proposed method for locating faults has a high level of accuracy in location, computational efficiency, and reliability. It can accurately identify fault segments and locations in hybrid transmission line systems.
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Authors and Affiliations

Caixia Tao
1
Baosheng Xing
1
Taiguo Li
1

  1. School of Automation and Electrical Engineering, Lanzhou Jiaotong University, Gansu Province, China
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Abstract

When a single line-to-ground fault occurs in the ungrounded distribution system, the steady-state fault current is relatively small for fault analysis and the transient fault current is observable, which can be used for faulted feeder identification and location. The principal frequency component retains most of the characteristics of the transient current. The principal frequency is related to the distance from the fault point to the substation and can be used for fault location. This paper analyzes the sequence network model of a single line-to-ground fault in the distribution network, and gives a method for principal frequency calculation. Depending on the characteristics of the maximum amplitude of the principal frequency component of the faulted feeder, the method of faulted feeder identification is given. Based on the complementary characteristics of the phase angle of the principal frequency component of the fault current and the phase angle at the substation bus, the faulted section location is carried out. MATLAB simulation is used to verify the effectiveness of the faulted feeder identification and location method.

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Authors and Affiliations

Ling Liu
ORCID: ORCID
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Abstract

This paper proposes a new fault location method in radial medium voltage distribution networks. The proposed method only uses the measurement data at the feeder beginning to approximate the characteristic equation showing the dependence between the positive-sequence voltage and phase angle at the monitoring point with the distance to the fault location for each fault type on each line segment. To determine these characteristic equation coefficients, the entire distribution network will be modeled and simulated by four types of faults at different locations along the lines to build the initial database. Based on this database, the mathematical functions in MATLAB software are applied to approximate these coefficients corresponding to each type of fault for each line segment in the network. Then, from the current and voltage measurement data at the feeder beginning, the algorithms of global search, comparison, and fault ranking are used to find out where the fault occurs on the distribution network. Two types of distribution network with and without branches are studied and simulated in this paper to verify and evaluate the effectiveness of the proposed method.
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Authors and Affiliations

Truong Ngoc-Hung
1
ORCID: ORCID

  1. Department of I.T., FPT University – Quy Nhon A.I Campus, Dong Da ward, Quy Nhon city, Viet Nam
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Abstract

As the capacity and scale of distribution networks continue to expand, and distributed generation technology is increasingly mature, the traditional fault location is no longer applicable to an active distribution network and "two-way" power flow structure. In this paper, a fault location method based on Karrenbauer transform and support vector machine regression (SVR) is proposed. Firstly, according to the influence of Karrenbauer transformation on phase angle difference before and after section fault in a low-voltage active distribution network, the fault regions and types are inferred preliminarily. Then, in the feature extraction stage, combined with the characteristics of distribution network fault mechanism, the fault feature sample set is established by using the phase angle difference of the Karrenbauer current. Finally, the fault category prediction model based on SVR was established to solve the problem of a single-phase mode transformation modulus and the indistinct identification of two-phase short circuits, then more accurate fault segments and categories were obtained. The proposed fault location method is simulated and verified by building a distribution network system model. The results show that compared with other methods in the field of fault detection, the fault location accuracy of the proposed method can reach 98.56%, which can enhance the robustness of rapid fault location.
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Authors and Affiliations

Siming Wang
1
Zhao Kaikai
1

  1. School of Automation and Electrical Engineering, Lanzhou Jiaotong University, China
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Abstract

Accurate and reliable fault location is necessary for ensuring the safe and reliable operation of the VSC-HVDC transmission system. This paper proposed a single-terminal fault location method based on the fault transient characteristics of the two-terminal VSCHVDC transmission system. The pole-to-pole transient fault process was divided into three stages, the time-domain expression of the DC current during the diode freewheel stage was used to locate the fault point, and a criterion for judging whether the fault evolves to the diode freewheel stage was proposed. Taking into account the enhancing effect of the opposite system to the fault current, theDCside pole-to-ground fault networkwas equated to a fourth-order circuit model, the relationship of fault distance with the characteristic roots of fault current differential equationwas derived, and the Prony algorithmwas utilized for datafitting to extract characteristic roots to realize fault location. A two-terminal VSC-HVDC transmission system was modelled in PSCAD/EMTDC. The simulation result verifies that the proposed principle can accurately locate the fault point on the VSC-HVDC transmission lines.
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Authors and Affiliations

Yanxia Zhang
1
Anlu Bi
1
Jian Wang
1
Fuhe Zhang
1
Jingyi Lu
1

  1. School of Electrical and Information Engineering, Tianjin University, China

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