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Abstract

Refined Schwarz-Christoffel (SC) conformal transformations allow us to perform reliable quantitative evaluation of the accuracy of local computation of electric and magnetic fields with limited effort, which can be useful to complement well known comparisons of global results. In this paper some examples are presented for mesh point potentials obtained by means of finite difference (FD) methods, but it is possible that similar considerations will be useful in the case of finite element methods (FEM) or meshless computations too.

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Authors and Affiliations

Eugenio Costamagna
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Abstract

The aim of this paper is to present methods of digitally synthesising the sound generated by vibroacoustic systems with distributed parameters. A general algorithm was developed to synthesise the sounds of selected musical instruments with an axisymmetrical shape and impact excitation, i.e., Tibetan bowls and bells. A coupled mechanical-acoustic field described by partial differential equations was discretized by using the Finite Element Method (FEM) implemented in the ANSYS package. The presented synthesis method is original due to the fact that the determination of the system response in the time domain to the pulse (impact) excitation is based on the numerical calculation of the convolution of the forcing function and impulse response of the system. This was calculated as an inverse Fourier transform of the system’s spectral transfer function. The synthesiser allows for obtaining a sound signal with the assumed, expected parameters by tuning the resonance frequencies which exist in the spectrum of the generated sound. This is accomplished, basing on the Design of Experiment (DOE) theory, by creating a meta-model which contains information on its response surfaces regarding the influence of the design parameters. The synthesis resulted in a sound pressure signal in selected points in space surrounding the instrument which is consistent with the signal generated by the actual instruments, and the results obtained can improve them.
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Authors and Affiliations

Andrzej Gołaś
Roman Filipek
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Abstract

An automated procedure based on evolutionary computation and Finite Element Analysis (FEA) is proposed to synthesize the optimal distribution of nanoparticles (NPs) in multi-site injection for a Magnetic Fluid Hyperthermia (MFH) therapy. Evolution Strategy and Non dominated Sorting Genetic Algorithm (NSGA) are used as optimization procedures coupled with a Finite Element computation tool.

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Authors and Affiliations

Paolo Di Barba
Fabrizio Dughiero
Elisabetta Sieni
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Abstract

The classic relationships concerning the harmonic content in the air gap field of three-phase machines are presented in form of series of rotating waves. The same approach is applied to modeling of permanent magnet motors with fractional phase windings. All main reasons of non-sinusoidal shape of flux density distribution, namely, magnets’ shape and their placement, slotting, magnetic saturation and eccentricity are also related to their counterparts in modal-frequency spectrum. The Fourier 2D spectrum of time-stepping finite element solution is confronted with results of measurements, with special attention paid to accuracy of both methods.

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Authors and Affiliations

Pawel Witczak
Witold Kubiak
Marcin Lefik
Jacek Szulakowski
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Abstract

In the paper, methodologies for the magnetic field simulation in an axial flux permanent magnet coreless (AFPMC) motor have been proposed and discussed. Two approaches have been considered and investigated, both based on representing the 3D field distribution by superimposing axisymmetric 2D patterns. The first of studied approaches applies directly to the Biot-Savart law while the second uses a 2D axisymmetric finite element method. The selected results of magnetic field distributions and electromagnetic torque characteristics for the considered AFPMC motor have been presented and compared with results obtained using the commercial FEM package 'Maxwell'. The elaborated algorithms have been incorporated into the design routines allowing multi-parameter optimisation of the considered motor construction.

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Authors and Affiliations

Rafał M. Wojciechowski
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Abstract

The paper presents methods of analytical and measurement-based determination of pressures acting on sheet metal in the process of electrodynamic forming by means of flat inductors generating pulse magnetic field. Pressures are determined for sheet metal of different thicknesses processed by means of circular and elliptical spiral inductors. The paper describes also examples of copper and aluminium sheet metal forming conducted by means of the analysed inductors and shaped forming dies.
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Authors and Affiliations

Józef Bednarski
Gerard Głuch
Andrzej Kot
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Abstract

It is not easy to make the insulators of the railway catenary for the dry and cold environment of the icy Qinghai-Tibet plateau, without causing serious ice-related flashover accidents. To study the operating status of catenary icing insulators, a two-dimensional icing model of catenary cantilever insulators was established based on the winter environmental characteristics of the Golmud station on the Qinghai-Tibet Railway. Compared different directions of ice growth, the spatial electric field distribution, and surface temperature distribution characteristics of icing insulatorswere analyzed by multi-physical field coupling simulation. The results show that as the thickness of the ice layer increases and the length of the icicle increases, the field intensity of the insulator gradually increases, and the surface temperature continues to rise. When the ice edge grows vertically downward, the electric field intensity of the insulator is the smallest, and the electric field intensity is the largest when the ice edge grows horizontally. Although the surface temperature of the insulator will rise with the increase of icing degree, it is lower than the freezing point and will not have a great impact on insulation performance. Secondly, when the cantilever insulator is arranged obliquely, the increase in the inclination angle will cause the electric field to increase and the temperature to rise slightly, so the inclination angle of the oblique cantilever should be reduced as much as possible during installation. Finally, the insulator with better insulation performance is obtained by optimizing the structure of the flat cantilever insulator.
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Bibliography

[1] Meng Hong, Qinghai-Tibet Railway: The Magical "Sky Road" on the Roof of theWorld, Party Member’s Digest, no. 11, pp. 38–40 (2019).
[2] Fofana I., Farzaneh M. et al., Dynamic Modeling of Flashover Process on Insulator under Atmospheric Icing Conditions, 2001 Annual Report Conference on Electrical Insulation and Dielectric Phenomena, Toronto, Canada, pp. 605–608 (2001).
[3] Tavakoli C., Farzaneh M., Fofana I. et al., Dynamics and Modeling of AC Arc on Surface of Ice, IEEE Transactions on Dielectrics and Electrical Insulation, vol. 13, no. 06, pp. 1278–1283 (2006).
[4] Zhao Jiayao, Study on AC Flashover Characteristics of Nature Icing Suspension Insulator (Short) Strings, PhD Thesis, Chongqing University, Chongqing (2019).
[5] Zhang Zhijin, Cheng Yang, Zhao Jiayao et al., AC Flashover Performances of Artificial Icing and Nature Icing for XP-160 Insulator String, High Voltage Engineering, vol. 44, no. 09, pp. 2777–2784 (2018).
[6] Ciesielka W., Gołas A. et al., Reliability improvement of power distribution line exposed to extreme icing in Poland, Archives of Electrical Engineering, vol. 68, no. 05, pp. 1113–1125 (2020).
[7] Mhaguen N., Development of Dynamic Models for Predicting the Critical Flashover Voltage of Insulators Covered with Ice Based on Finite Element Method, Thesis of Master’s Degree, University of Québec, Canada (2011).
[8] Volat C., Farzaneh M. et al., Improved FEM models of one- and two-arcs to predict AC critical flashover voltage of ice-covered insulators, IEEE Transactions on Dielectrics and Electrical Insulation, vol. 18, no. 02, pp. 393–400 (2011).
[9] Lu Jiazheng, Xie Pengkang et al., Electric field simulation and sheds optimization of anti- icing and anti- lightning insulator under heavy icing condition, Electric Power Automation Equipment, vol. 38, no. 03, pp. 199–204 (2018).
[10] Tu Yewei, Xia Qiangfeng, Simulation of Space Electric Field Distribution Around 220 kV Porcelain Insulator String (XP-160) and the Influencing Factors, High Voltage Apparatus, vol. 48, no. 03, pp. 67–74 (2012).
[11] Qi Guiming, Wang fake, He Haicheng et al., Surface and low altitude wind field characteristics in Golmud city, Journal of Arid Land Resources and Environment, vol. 24, no. 06, pp. 118–120 (2010).
[12] Hu Yuyao, Study on Dynamic Model for Icing with Wet Growth Process and Ice Flashover Voltage Prediction of Suspension Insulators, Master Thesis, Chongqing University, Chongqing (2017).
[13] Luo Jian, The Optimization of the System Parameters and Cantilever and Positioning Device of Overhead Contact System of High-speed Railway, PhD Thesis, Southwest JiaotongUniversity, Chengdu (2017).
[14] Zhang Yuexin, Study on Catenary’s Construction Techniques in High-speed Electric Railway, PhD Thesis, Southwest Jiaotong University, Chengdu (2006).
[15] Sharma R.P., Seema Tinker et al. Effect of Convective Heat and Mass Conditions in Magnetohydrodynamic Boundary Layer Flow with Joule Heating and Thermal Radiation, International Journal of Applied Mechanics and Engineering, vol. 25, no. 03 (2020).
[16] Liao Jiajun, Yang Lin, Hao Yanpeng, Simulation of Electric Field for 110 kV Iced Composite Insulator in Melting Period, High Voltage Apparatus, vol. 51, no. 03, pp. 47–54 (2015), DOI: 10.13296/ j.l001-1609.hva.2015.03.008.
[17] Ravisha M., Raghunatha K.R., Mamatha A.L., B oundary effects on electrothermal convection in a dielectric fluid layer, Archives of Electrical Engineering, vol. 40, no. 1, pp. 3–19 (2019).
[18] Van Brunt R.J., Stochastic properties of partial-discharge phenomena, Electrical Insulation, IEEE Transactions, vol. 26, iss. 5 (1991), DOI: 10.1109/14.99099.
[19] An Dawei, Study on Needle-plate corona Discharge and Migration Characteristics of Ion Space Charge, PhD Thesis, Chongqing University, Chongqing (2017).

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Authors and Affiliations

Sihua Wang
1
ORCID: ORCID
Junjun Wang
1
Lijun Zhou
1
Long Chen
1
ORCID: ORCID
Lei Zhao
1

  1. Lanzhou Jiaotong University, China
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Abstract

Mixed boundary-value problem for periodic baffles in acoustic medium is solved with help of the method developed earlier in electrostatics. The nice feature of the method is that the resulting matrices are relatively easy for computations and that the results satisfy exactly the energy conservation law. Illustrative numerical examples present the wave-beam steering (in the far-field) in a baffle system that may be considered as a model of one-dimensional ultrasonic transducer array.

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Authors and Affiliations

Yuriy Tasinkevych
Eugeniusz Danicki
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Abstract

This article presents a reappraisal of the concept of the 1890–1918 literary period from the perspective of sociology of literature, and in particular Pierre Bourdieu’s theory of literary field ( le champ littéraire), set out in his Les règles de l’art (1992). It goes without saying that the turn of the 19th century saw the emergence of a modernist movement, or, an autonomous literary field, dedicated to ‘pure’ art and literature, divorced from any social obligations. Within the Bourdieuesque perspective the dynamics of the literary field can be examined from a number of perspectives with the aim of assessing the success or failure of its strategies of consecration (i.e. the building of legitimacy and prestige), the habitus of its key figures, or its role as a space of mediation between external forces ( les logiques externs) and the autonomy of literary production. The ultimate aim of conducting all those probes is to validate the claim that the 1890–1910 modernist literary field was indeed autonomous. In fact, its emergence in Poland bore a marked resemblance to the developments in mid-19th century French literature, as described by Bourdieu. The peculiar character of the Polish literary field resulted mainly from the one external factor, Poland’s political status until the declaration of independence in 1918.
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Bibliography

● Berent W., Próchno, oprac. J. Paszek, wyd. II, Wrocław 1998.
● Bourdieu P., Dystynkcja. Społeczna krytyka władzy sądzenia, przeł. P. Biłos, Warszawa 2005.
● Bourdieu P., Reguły sztuki. Geneza i struktura pola literackiego, przeł. A. Zawadzki, Kraków 2001.
● Brzozowski S., My młodzi, [w:] Programy i dyskusje literackie Młodej Polski, oprac. M. Podraza-Kwiatkowska, wyd. III, Wrocław 2000.
● Casanova P., Światowa republika literatury, przeł. E. Gałuszka, A. Turczyn, Kraków 2017.
● Czabanowska-Wróbel A., „Kolega, rówieśnik, towarzysz i przyjaciółka”. Miejsce Maryli Wolskiej wśród lwowskich Płanetników, „Ruch Literacki”, 2019, nr 2.
● Czabanowska-Wróbel, A., Wacław Rolicz-Lieder niewczesny i nowoczesny, „Wiek XIX” 2017.
● Franczak J., Błądzące słowa. Jacques Rancière i filozofia literatury, Warszawa 2017.
● Franczak J., Jacques Rancière: historia literatury i polityka, „Teksty Drugie”, 2012, nr 3.
● Głowiński M., Ekspresja i empatia. Studia o młodopolskiej krytyce literackiej, Kraków 1997.
● Heinich N., Być artystą. Rzecz o przekształceniach statusu malarzy i rzeźbiarzy, przeł. L. Mazur, Warszawa 2007.
● Heinich N. , Socjologia sztuki, przekład A. Karpowicz, Warszawa 2010.
● Jankowicz G., Marecki P., Palęcka A., Sowa J., Warczok T., Literatura polska po 1989 roku w świetle teorii Pierre’a Bourdieu, Kraków 2014.
● Kaufman J., Ego. Socjologia jednostki, przeł. K. Wakar, Warszawa 2004.
● Kluba A., Autotelizm, [w:] Słownik polskiej krytyki literackiej 1764–1918. Pojęcia, terminy, zjawiska, przekroje, t. 1, red. J. Bachórz, G. Borkowska, T. Kostkiewiczowa, M. Rudkowska, M. Strzyżewski, Toruń 2016.
● Lahire B., La Condition littéraire. La double vie des écrivains, Paryż 2006.
● Lahire B. , Podwójne życie pisarzy, przeł. I. Okulska, [w:] Socjologia literatury. Antologia, red. G. Jankowicz, M. Tabaczyński, Kraków 2015.
● Leśmian B., Szkice literackie, oprac. J. Trznadel, Warszawa 2011.
● Matuchniak-Krasuska A., Zarys socjologii sztuki Pierre’a Bourdieu, Warszawa 2010.
● Matuszek G., Stanisław Przybyszewski – pisarz nowoczesny, Kraków 2008.
● Miodońska-Brookes E., „Sprzykrzyły mi się biedne słowa…” czyli krytyk przeciw poecie, [w:] K.M. Górski, Wiersze wybrane, Kraków 1987.
● Niedźwiedź D., Jak Tadeusz Żeleński stworzył Boya. Strategie, autokreacje, wizerunki, rozprawa doktorska, Uniwersytet Jagielloński 2021.
● Okulicz-Kozaryn M., Okulicz-Kozaryn R., Tropami Bractwa Wielkiego Dzwonu. Szkice o literaturze przełomu XIX i XX wieku, Poznań 2020.
● Paczoska E., Stolica nowoczesności? W poszukiwaniu „tekstu lwowskiego”, [w:] Moder-nistyczny Lwów. Teksty życia, teksty sztuki, pod red. E. Paczoskiej i D.M. Osińskiego, Warszawa 2009.
● Popiel M., Wyspiański. Mitologia nowoczesnego artysty, Kraków 2007.
● Potocki A., Polska literatura współczesna, cz. I, Kult zbiorowości 1860–1890, Warszawa 1911.
● Rancière J., Polityka literatury, przeł. J. Franczak, [w:] Socjologia literatury. Antologia, red. G. Jankowicz, M. Tabaczyński, Kraków 2015.
● Rolicz-Lieder W., Poezje wybrane, wstęp, wybór i oprac. M. Podraza-Kwiatkowska, Kraków 2003.
● Siwiec M., Norwid, Baudelaire i reguły sztuki, „Teksty Drugie”, 2020, nr 5.
● Skucha M., Niesytość pragnienia. W kręgu młodopolskiej liryki kobiet, Kraków 2016.
● Szczepańska A., Chimera. Tekstowa kolekcja Zenona Przesmyckiego, Gdańsk 2009.
● Wolska M., Obertyńska B., Wspomnienia, Warszawa 1974.
● Wyspiański S., Dzieła zebrane, t. 11, Rapsody, hymny, wiersze, Kraków 1961.
● Zabawa K., „Cień niesytej duszy”, [w:] M. Wolska, Poezje wybrane, Kraków 2002.
● Zarychta P., Widzialność tłumacza jako kapitał. O działalności Ryszarda Wojnakowskiego na przykładzie serii „Śpiewać to być. Współcześni poeci austriaccy znani i nieznani”, [w:] Wyjść tłumaczowi naprzeciw. Miejsce tłumacza w najnowszych badaniach translato-logicznych, red. J. Kita-Huber, R. Makarska, Kraków 2020.
● Ziejka F., Paryż młodopolski, Warszawa 1995.
● Zięba J., Pieniądz i słowo. Nowoczesne paradoksy Leśmianowskiego języka poetyckiego, „Teksty Drugie”, 2010, nr 6.
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Authors and Affiliations

Anna Czabanowska-Wróbel
1
ORCID: ORCID

  1. Uniwersytet Jagielloński, Kraków
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Abstract

The main thesis of this paper is the assertion that, in contrast to the prevailing opinion about the decline or deep crisis of the intelligentsia, it is precisely this social group—and especially its elite—that is the dominant actor in social life. This thesis emerges from an analysis of the role of the intelligentsia, using ‘longue durée’ categories and also the broader international perspective of ‘world system theory’, in which Poland is assigned to the (semi)-periphery. Elements of Pierre Bourdieu’s theory, particularly the idea of cultural capital and the field of power, are an important theoretical poin in the author’s argument. In this view, the structurally privileged position of the intelligentsia in Poland is understood as an aspect of the specific configuration of the Polish field of power, in which—at least since the end of the First World War—cultural capital turns out to be the strongest and most stable dimension in the creation and reproduction of elite social positions.

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Authors and Affiliations

Tomasz Zarycki
Tomasz Warczok
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Abstract

The article presents scientific achievements of Alfred Nobel Memorial Prize Laureates in economic sciences in 2019: Esther Duflo, Abhijit Banerjee, and Michael Kremer. The paper describes their contribution to the research on the sources of poverty in the world and the ways of alleviating it, and their contribution to the development of experimental research in social sciences using randomized control trials (RCT). In this context, the authors explain the reasons for growing popularity of this approach in development economics and discuss its strengths and weaknesses.

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Authors and Affiliations

Dominik Buttler
Jan Szambelańczyk
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Abstract

A novel method of active noise control using adaptive radiation sound sources is investigated. A finite element model of a modal enclosed sound field is excited harmonically, representing a noise field in the low-frequency range. The control sources are comprised of elementary dipole sources for which the driving signals are adjusted by an optimization method. Two set-up cases of the proposed compound sources are investigated. The coupling of the control sources with the modal sound field is discussed. The simulated performance of the proposed method is compared with that of a system with distributed simple sources and the results show the effectiveness of the sources with adaptive radiation for active noise control in small enclosures.

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Authors and Affiliations

Marios Giouvanakis
Christos Sevastiadis
George Papanikolaou
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Abstract

Dolichos ( Lablab purpureus L.) is a drought tolerant legume used as food/feed and improvement of soil fertility. The production of dolichos in Kenya, Nakuru County is however limited by insect pests like bean aphids, pod borers and whiteflies. Field studies were conducted to determine the effect of cropping systems (dolichos monocrop and maize-dolichos intercrop) and field margin vegetation on bean aphids and their natural enemies. The experiment was conducted in Njoro (high field margin vegetation) and Rongai (low field margin vegetation) during May- December 2019 and MarchNovember 2020 cropping seasons. Bean aphid percent incidence, severity of damage and abundance was assessed at seedling, early vegetative, late vegetative and flowering dolichos growth stages. The populations of natural enemies in the plots and field margin vegetation were monitored using pan traps and sweep nets. Species diversity and composition of the field margin vegetation was determined using a quadrat. Results showed that location and cropping system had significant effects on bean aphid infestations. A high bean aphid incidence (38.13%) was observed in Njoro compared to Rongai (31.10%). Dolichos monocrop had significantly higher bean aphid infestation (51.63%) than the maize-dolichos intercrop system (24.62%). A highly diverse Shannon-weaver index was observed in Rongai (1.90) compared to Njoro (1.67). Dolichos monocrop had a more diverse Shannon-weaver index (1.8) than the maize-dolichos intercrop system (1.7). Rongai had the most abundant annual and perennial field margin vegetation species. The field margin species richness and diversity were higher in Rongai (81%) than in Njoro (54%). The findings of this study have demonstrated that a maize-dolichos intercrop in Rongai can reduce bean aphid damage in dolichos.
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Bibliography


Abate T., van Huis A., Ampofo J.K.O. 2000. Pest management strategies in traditional agriculture: an African perspective. Annual Review of Entomology 45 (1): 631-659. DOI: https://doi.org/10.1146/annurev.ento.45.1.631
Amaral D.S., Venzon M., Duarte M.V., Sousa F.F, Pallini A., Harwood J.D. 2013. Non-crop vegetation associated with chili pepper agroecosystems promote the abundance and survival of aphid predators. Biological Control 64 (3): 338-346. DOI: https://doi.org/10.1016/j.biocontrol.2012.12.006
Arnett R.H., Jacques R.L. 1981. Simon and Schuster's guide to insects. Simon and Schuster.
Asbjornsen H., Hernandez-Santana V., Liebman M., Bayala J., Chen J., Helmers M., Ong C.K., Schulte L.A. 2014. Targeting perennial vegetation in agricultural landscapes for enhancing ecosystem services. Renewable Agriculture and Food Systems 29 (2): 101-125. DOI: https://doi.org/10.1017/S1742170512000385
Bajwa A.A., Mahajan G., Chauhan B.S. 2015. Nonconventional weed management strategies for modern agriculture. Weed Science 63 (4): 723-747. DOI: https://doi.org/10.1614/WS-D-15-00064.1
Balzan M.V., Moonen A.C. 2014. Field margin vegetation enhances biological control and crop damage suppression from multiple pests in organic tomato fields. Entomologia Experimentalis et Applicata 150 (1): 45-65. DOI: https://doi.org/10.1111/eea.12142
Cheruiyot E.K., Mumera L.M., Nakhone L.N., Mwonga S.M. 2003. Effect of legume-managed fallow on weeds and soil nitrogen in following maize ( Zea mays L.) and wheat ( Triticum aestivum L.) crops in the Rift Valley highlands of Kenya. Australian Journal of Experimental Agriculture 43 (6): 597-604. DOI: https://doi.org/10.1071/EA02033
Cullis C., Kunert K.J. 2017. Unlocking the potential of orphan legumes. Journal of Experimental Botany 68 (8): 1895-1903. DOI: https://doi.org/10.1093/jxb/erw437
Damalas C.A., Eleftherohorinos I.G. 2011. Pesticide exposure, safety issues, and risk assessment indicators. International Journal of Environmental Research and Public Health 8 (5): 1402-1419. DOI: https://doi.org/10.3390/ijerph8051402
De Bello F., Lepš J., Sebastià, M.T. 2006. Variations in species and functional plant diversity along climatic and grazing gradients. Ecography 29 (6): 801-810. DOI: https://doi.org/10.1111/j.2006.0906-7590.04683.x
Dixon A.F.G. 2012. Aphid ecology an optimization approach. Springer Science & Business Media.
Dixon A.F.G., Agarwala B.K. 1999. Ladybird-induced life-history changes in aphids. Proceedings of the Royal Society of London. Series B: Biological Sciences 266 (1428): 1549-1553.
Dostálek T., Rokaya M.B., Münzbergová Z. 2018. Altitude, habitat type and herbivore damage interact in their effects on plant population dynamics. PloS One 13 (12): e0209149. DOI: https://doi.org/10.1371/journal.pone.0209149
Elsharkawy M.M., El-Sawy, M.M. 2015. Control of bean common mosaic virus by plant extracts in bean plants. International Journal of Pest Management 61 (1): 54-59. DOI: https://doi.org/10.1080/09670874.2014.990947
Farkas Á., Molnár R., Morschhauser T., Hahn I. 2012. Variation in nectar volume and sugar concentration of Allium ursinum L. ssp. ucrainicum in three habitats. The Scientific World Journal 2012: 138579. DOI: https://doi.org/10.1100/2012/138579
Farooq M., Jabran K., Cheema Z.A., Wahid A., Siddique K.H. 2011. The role of allelopathy in agricultural pest management. Pest Management Science 67 (5): 493-506. DOI: https://doi.org/10.1002/ps.2091
Forrest J.R. 2016. Complex responses of insect phenology to climate change. Current Opinion in Insect Science 17: 49-54. DOI: https://doi.org/10.1016/j.cois.2016.07.002
Glaze-Corcoran S., Hashemi M., Sadeghpour A., Jahanzad E., Afshar R.K., Liu X., Herbert S.J. 2020. Understanding intercropping to improve agricultural resiliency and environmental sustainability. Advances in Agronomy 162: 199-256. DOI: https://doi.org/10.1016/bs.agron.2020.02.004
González E., Salvo A., Valladares G. 2020. Insects moving through forest-crop edges: a comparison among sampling methods. Journal of Insect Conservation 24 (2): 249-258. DOI: https://doi.org/10.1007/s10841-019-00201-6
Grez A.A., Gonzalez R.H. 1995. Resource concentration hypothesis: effect of host plant patch size on density of herbivorous insects. Oecologia 103 (4): 471-474.
Guerrieri E., Digilio M.C. 2008. Aphid-plant interactions: a review. Journal of Plant Interactions 3 (4): 223-232.
He H.M., Liu L.N., Munir S., Bashir N.H., Yi W.A.N.G., Jing Y.A.N.G., Li C.Y. 2019. Crop diversity and pest management in sustainable agriculture. Journal of Integrative Agriculture 18 (9): 1945-1952. DOI: https://doi.org/10.1016/S2095-3119(19)62689-4
Hrček J., McLean A.H., Godfray H.C.J. 2016. Symbionts modify interactions between insects and natural enemies in the field. Journal of Animal Ecology 85 (6): 1605-1612. DOI: https://doi.org/10.1111/1365-2656.12586
Jaetzold R., Hornetz B., Shisanya C.A., Schmidt H. 2012. Farm management handbook of Kenya Vol I-IV (Western Central Eastern Nyanza Southern Rift Valley Northern Rift Valley Coast). Nairobi: Government Printers.
Khan Z.R., Pickett J.A. 2004. The ‘push-pull’strategy for stemborer management: a case study in exploiting biodiversity and chemical ecology. Ecological engineering for pest management: Advances in Habitat Manipulation for Arthropods. p. 155-164. In: “Ecological Engineering for Pest Management: Advances in Habitat Manipulation for Arthropods” (S.D. Wratten, M.A. Altieri, G.M. Gurr, eds.). CABI International, Wallingford, Oxon (CABI)
Leksono A.S., Batoro J., Zairina A. 2018. Abundance and composition of arthropods in a paddy field collected by pan traps. In: AIP Conference Proceedings. AIP Publishing LLC, 2019, No. 1, p. 04002
Li J., Wang Z., Tan K., Qu Y., Nieh J.C. 2014. Giant Asian honeybees use olfactory eavesdropping to detect and avoid ant predators. Animal Behaviour 97: 69-76. DOI: https://doi.org/10.1016/j.anbehav.2014.08.015
Lopes T., Hatt, S. Xu, Q., Chen J., Liu Y. Francis F. 2016. Wheat (Triticum aestivum L.)‐based intercropping systems for biological pest control. Pest Management Science 72 (12): 2193-2202. DOI: https://doi.org/10.1002/ps.4332
Mahajan M., Fatima S. 2017. Frequency, abundance, and density of plant species by list count quadrat method. International Journal of Multidisciplinary Research 3 (7): 1-8.
Mbata G.N., Shu S., Phillips T.W. Ramaswamy S.B. 2004. Semiochemical cues used by Pteromalus cerealellae (Hymenoptera: Pteromalidae) to locate its host, Callosobruchus maculatus (Coleoptera: Bruchidae). Annals of the Entomological Society of America 97 (2): 353-360. DOI: https://doi.org/10.1093/aesa/97.2.353
Mkenda P., Mwanauta R., Stevenson P.C., Ndakidemi P., Mtei K. Belmain S.R. 2015. Extracts from field margin weeds provide economically viable and environmentally benign pest control compared to synthetic pesticides. PLoS One 10 (11): e0143530. DOI: https://doi.org/10.1371/journal.pone.0143530
Nahashon C.K., Benson M.M., Stephen M.M. 2016. Effects of irrigated and rain-fed conditions on infestation levels of thrips (Thysanoptera: Thripidae) infesting Dolichos lablab (L.) in Eastern Kenya. African Journal of Agricultural Research 11 (18): 1656-1660. DOI: https://doi.org/10.5897/AJAR2015.10721
Njarui D.M.G. Mureithi J.G. 2010. Evaluation of lablab and velvet bean fallows in a maize production system for improved livestock feed supply in semiarid tropical Kenya. Animal Production Science 5 (3): 193-202. DOI: https://doi.org/10.1071/AN09137
Novgorodova T.A., Gavrilyuk A.V. 2012. The degree of protection different ants (Hymenoptera: Formicidae) provide aphids (Hemiptera: Aphididae) against aphidophages. European Journal of Entomology 109 (2): 187-196.
Perdikis D., Fantinou A., Lykouressis D. 2011. Enhancing pest control in annual crops by conservation of predatory Heteroptera. Biological Control 59 (1): 13-21. DOI: https://doi.org/10.1016/j.biocontrol.2011.03.014
Pielou E.C. 1966. The measurement of diversity in different types of biological collections. Journal of Theoretical Biology 13: 131-144.
Quicke D.L. 2015. The Braconid and Ichneumonid Parasitoid Wasps: Biology, Systematics, Evolution and Ecology. John Wiley & Sons, 740 pp. DOI: https://doi.org/10.1002/9781118907085
Rekha C., Mallapur C.P. 2009. Studies on pests of dolichos beans in northern Karnataka. Agricultural Science 2: 407-409.
Root R.B. 1973. Organization of a plant-arthropod association in simple and diverse habitats: the fauna of collards (Brassica oleracea). Ecological Monograph 43 (1): 95-124. DOI: https://doi.org/10.2307/1942161
SAS Institute inc. 2002. SAS for Windows v. 8. Cary, NC, U.S.A.
Saunders M.E., Luck G.W. 2013. Pan trap catches of pollinator insects vary with habitat. Australian Journal of Entomology 52 (2): 106-113. DOI: https://doi.org/10.1111/aen.12008
Soetan K.O., Fafunso M.A. 2010. Studies on the proximate and mineral composition of three varieties of lablab beans (Lablab purpureus). International Journal of Applied Agricultural Research 5 (3): 291-300.
Songa J.M., Jiang N., Schulthess F., Omwega C. 2007. The role of intercropping different cereal species in controlling lepidopteran stem borers on maize in Kenya. Journal of Applied Entomology 131 (1): 40-49. DOI: https://doi.org/10.1111/j.1439-0418.2006.01116.x
Spafford R.D., Lortie C.J. 2013. Sweeping beauty: is grassland arthropod community composition effectively estimated by sweep netting? Ecology and Evolution 3 (10): 3347-3358. DOI: https://doi.org/10.1002/ece3.688
Sujayanand G.K., Sharma R.K., Shankarganesh K., Saha S. Tomar R.S. 2015. Crop diversification for sustainable insect pest management in eggplant (Solanales: Solanaceae). Florida Entomologist 98 (1): 305-314. DOI: https://doi.org/10.1653/024.098.0149
Thejaswi L., Mohan I., Naik M., Majunatha M. 2007. Studies of population dynamics of pests’ complex of field beans (Lablab purpureus L.) and natural enemies of pod borers. Karnataka Agriculture Science 3: 399-402.
Tiroesele B., Obopile M., Karabo O. 2019. Insect diversity and population dynamics of natural enemies under sorghum-legume intercrops. Transactions of the Royal Society of South Africa 74 (3): 258-267. DOI: https://doi.org/10.1080/0035919X.2019.1658654
Vellichirammal N.N., Gupta P., Hall T.A., Brisson J.A. 2017. Ecdysone signaling underlies the pea aphid transgenerational wing polyphenism. Proceedings of the National Academy of Sciences 114 (6): 1419-1423. DOI: https://doi.org/10.1073/pnas.1617640114
Wäckers F.L., Romeis J., van Rijn P. 2007. Nectar and pollen feeding by insect herbivores and implications for multitrophic interactions. Annuals Review Entomology 52: 301-323. DOI: https://doi.org/10.1146/annurev.ento.52.110405.091352
Webster B., Cardé R.T. 2017. Use of habitat odour by host‐seeking insects. Biological Reviews 92 (2): 1241-1249. DOI: https://doi.org/10.1111/brv.12281
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Authors and Affiliations

Christine N. Mwani
1
ORCID: ORCID
Jane Nyaanga
1
Erick K. Cheruiyot
1
Joshua O. Ogendo
1
Philip K. Bett
2
Richard Mulwa
1
Philip C. Stevenson
3
Sarah E.J. Arnold
3 4
Steven R. Belmain
3

  1. Crops, Horticulture and Soils, Egerton University, Kenya
  2. Biological Sciences, Egerton University, Kenya
  3. Jodrell Laboratory, Royal Botanic Gardens Kew, Richmond, UK
  4. Nelson Mandela African Institute of Science and Technology, Arusha, Tanzania
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Abstract

The Exodus method is applied to solve Fourier-Kirchoff's equation in heat transfer problems for flat plate solar collectors. Probabilistic models have been presented for the steady and non-steady conditions. The mathematical description of these models has been derived on the basis of the analogy between the conduction difference equation and the equation describing walking particle movement. The results of computations performed by the Exodus method have been compared to the results obtained by the Equivalent Thermal Network and the Finite Difference methods. The Exodus procedure allows the influence of changeable weather and operating conditions to be considered in calculations.
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Authors and Affiliations

Alicja Siuta-Olcha
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Abstract

Complex gaps may be formed when carrying out live working in substations, while the discharge characteristics of complex gaps are different from those of single gaps. This paper focuses on the prediction of critical 50% positive switching impulse breakdown voltage ( U 50–crit + of phase-to-phase complex gaps formed in 220 kV substations. Firstly, several electric field features were defined on the shortest discharge path of the complex gap to reflect the electric field distribution. Then support vector machine (SVM) prediction models were established according to the connection between electric field distribution and breakdown voltage. Finally, the U 50–crit¸+ data of the complex gap were obtained through twice electric field calculations and predictions. The prediction results show that the minimum U 50–crit + of phase-to-phase complex gaps is 1147 kV, and the critical position is 0.9 m away from the high voltage conductor, accounting for 27% of the whole gap. Both critical position and voltage are in good agreement with the values provided in IEC 61472.
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Authors and Affiliations

Zhenpeng Tang
1
Yuancheng Qin
2
ORCID: ORCID
Changsheng Wu
1
Ronghuan Mai
1

  1. Jiangmen Power Supply Bureau Co., Ltd., China
  2. School of Automation, Wuhan University of Technology, China
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Abstract

The practical applications of bacteriophages are associated with the problems related to the intensification, optimization of process production of this biomaterial and the search for new methods of production. The production of bacteriophages requires a fine balance between the dynamic growth of the bacteriophage and the host. The electromagnetic field (EMF) is a promising biotechnological method for the process production of bacteriophages. This study evaluates the use of various types of EMF to enhance the process. It was found that the process production of bacteriophages is divided into two stages. In the first stage, the influence of various types of EMF on the proliferation process of bacteria (host) was analyzed. Secondly, the process production of bacteriophage was implemented for the optimal infection conditions under the action of the various types of EMF. Moreover, the study demonstrated that the most effective bacteriophage production was the process with the application of the rotating magnetic field (RMF), pulsed magnetic field (PMF) and the static magnetic field (SMF) with negative polarity.
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Authors and Affiliations

Rafał Rakoczy
1
ORCID: ORCID
Maciej Konopacki
1 2
ORCID: ORCID
Marian Kordas
1
ORCID: ORCID
Bartłomiej Grygorcewicz
2
ORCID: ORCID

  1. West Pomeranian University of Technology in Szczecin, Faculty of Chemical Technology and Engineering, Department of Chemical and Process Engineering, al. Piastów 42,71-065 Szczecin, Poland
  2. Pomeranian Medical University in Szczecin, Chair of Microbiology, Immunology and Laboratory Medicine, Department of Laboratory Medicine, al. Powstanców Wielkopolskich 72, 70-111 Szczecin, Poland
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Abstract

A ship built from ferromagnetic steel disturbs the uniformity of the Earth’s magnetic field. Changes of ship’s signature are due to the magneto-mechanical interaction of the hull with the Earth’s magnetic field. The ship’s magnetic field can be detected by a magnetic naval mine. For this reason, the vessel has to be demagnetized. There are several methods of ship’s de-perming. The results of experimental and computer simulations of the ship’s de-perming process using coils lying on the seabed are presented in this paper. The simulation of the de-perming process with a hysteresis model of ship’s steel was carried out in Opera-3d 18R2. The laboratory experiments were carried out using a physical ship’s model, several Helmholtz coils, magneto-resistive sensors, etc. The experiments and computer simulations have shown that ship’s de-perming with coils lying on the seabed is possible. The values of coil currents are over dozen times greater than those used in the standard method.

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Authors and Affiliations

Mirosław Wołoszyn
Piotr Jankowski
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Abstract

The Kibble balance experiment is used to redefine the kilogram as a unit of mass based on the Planck constant. To demonstrate and understand the basic principle of the Kibble balance, the National Institute of Standards (NIS)-Egypt has constructed a prototype Kibble balance that can measure gram-level masses with 0.01% relative uncertainty. Through the construction of this prototype, the challenges can be studied and addressed to overcome the weaknesses of NIS’s prototype. This study presents the design and construction of the prototype Kibble balance. It also focuses on the design and performance of the magnetic system, which is a crucial element of the Kibble balance. Analytical modeling and finite element analysis were used to evaluate and improve the magnet system. Several other aspects were also discussed, including the yoke’s material and enhancing the magnetic profile within the air gap of the magnet system. Over a vertical distance of 30 mm inside the air gap, the magnetic flux density was found to be 0.3 T, and the uniformity was found to be 8 x 10 -5.
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Authors and Affiliations

Sayed Emira
1
E.R. Shaaban
2
M.M. Rashad
3
Shaker A. Gelany
1

  1. National Institute of Standards (NIS), Tersa St, El-Haram, PO Box 136, Code 12211, Giza, Egypt
  2. Department of Physics, Faculty of Science, Al-Azhar University, Assiut 71542, Egypt
  3. Central Metallurgical Research and Development Institute (CMRDI), P.O. BOX. 87 Helwan, Egypt 11421
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Abstract

Here One important aspect of the process of anaerobic stabilisation of sewage sludge in medium and large sewage treatment plants, in addition to sludge mineralisation, is the acquisition of a valuable source of energy, which is biogas. There are well-known methods of intensifying the process of methane fermentation by subjecting sludge to disintegration using physical factors, i.e. ultrasonic field. Acetate production is the ratelimiting step in the acetate consumption pathway and affects the efficiency of the anaerobic stabilisation process. The product of the first stage of the process is also the substrate for the next stage. Therefore, it is advisable to subject sewage sludge to disintegration, which increases its susceptibility to biodegradation. Sludge modification with the above-mentioned method causes a significant increase in the concentration of organic substances in the supernatant liquid. The reflection of the physical and chemical transformations of sludge in the disintegration processes is the change in their structure expressed by the increase in the degree of particle dispersion. The disintegration of sludge using sonolysis is an effective process solution, both in terms of technology and energy, in terms of obtaining biogas, which is a valuable source of energy.
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Authors and Affiliations

Iwona Zawieja
1
ORCID: ORCID

  1. Faculty of Infrastructure and Environment, Czestochowa University of Technology,Dąbrowskiego 73, 42-201, Czestochowa, Poland, ORCID 0000-0002-4480-8736
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Abstract

Influence of magnetic field on parameters of normal detonation wave and cumulation process of cylindrical detonation wave in gaseous explosive mixture was examined. A review of applications of generalised Chester-Chisnell-Whitham (CCW) method used for analysis of implosion processes of detonation waves is presented.
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Authors and Affiliations

Jerzy Tyl
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Abstract

Seed coating technology combined with biopolymers offers an alternative method to reduce environmental contamination. However, when biological agents are incorporated, biopolymers would have diverse properties and effects. This underscores the necessity of exploring the optimal dosages and formulations of biopolymers to ensure the survival of beneficial microorganisms, seed quality, and proper storage. This study aimed to explore the effects of different sodium alginate and chitosan coating formulations on Trichoderma harzianum viability and canola seeds quality. The coating process involved mixing T. harzianum powder with sodium alginate, talc and chitosan in different doses, sequences and formulations. Trichoderma harzianum viability was assessed through colony-forming units per ml over time. Canola seed quality was evaluated by measuring radicle emergence, germination percentage, seedling growth, and field emergence. Sodium alginate, both alone and in combination with talc, improved T. harzianum viability immediately after treatment and during storage. These coatings did not impair seed germination and improved canola root growth. Among the different chitosan formulations, a 1 : 100 ratio in talc improved strain survival and root growth without affecting germination, radicle, and field emergence. Coating canola seeds is a practical alternative to the application of T. harzianum, sodium alginate and talc, as it preserves their viability over time and improves seedling performance. Chitosan formulations in acetic acid should be carefully developed to prevent negative effects on seeds or biological agents.
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Authors and Affiliations

Cyntia Lorena Szemruch
1
ORCID: ORCID
Marta Monica Astiz Gassó
2
Federico Augusto García
1
Carola Gonçalves Vila Cova
3
Silvia Sanchez
3
Yanina Ibáñez
4
Antonella Colinas
3

  1. Faculty of Agricultural Sciences, Institute of Research on Agricultural Production, Environment, and Health (IIPAAS), National University of Lomas de Zamora, Llavallol, Argentina
  2. Phytotechnical Institute of Santa Catalina, National University of La Plata, La Plata, Argentina
  3. Faculty of Agricultural Sciences, National University of Lomas de Zamora, Llavallol, Argentina
  4. Faculty of Agricultural Sciences, Institute of Research on Agricultural Production,Environment, and Health (IIPAAS), National University of Lomas de Zamora, Llavallol, Argentina
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Abstract

In this work we discussed the safety of the electric field environment in the No.3 carriage where the pantograph is located. DSA380 pantograph, CRH5 EMU carriage and passengers’ models were established to study the electric field exposure of passengers at different positions. The results showed that Emax in the carriage without passengers is 1.173 x 10 6 mV/m. Then we set the passengers’ positions according to the electric field distribution in the carriage without passengers and obtained that Emax in the carriage with passengers is 3.195 x 10 6 mV/m. It can be seen that the maximum induced electric field intensity of passengers at different positions appears on the soles of shoes, the maximum value is 3.028 x 105 mV/m, the maximum induced current density occurs at the ankle, its maximum value is 3.476 x 10 -5 A/m 2. It can be concluded that the maximum induced electric field intensity of passenger’s head appears in the cerebrospinal fluid area, with a maximum value of 202.817 mV/m, and the maximum induced electric field intensity of passenger’s head at the door is larger than that in the middle of the carriage. The maximum values of the induced electric field intensity in all tissues of passengers are much smaller than the basic limits of electromagnetic exposure to the public set by the International Commission on Non-Ionizing Radiation Protection (ICNIRP). This study indicated that the pantograph has little influence on the electric field environment in the carriage under working state, and will not cause any health hazard to the passengers in this working frequency electric field environment.
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Authors and Affiliations

Rui Tian
1
Jia-qi Zhang
1
Mai Lu
1
ORCID: ORCID

  1. Key Laboratory of Opto-Electronic Technology and Intelligent Control of Ministry of Education, Lanzhou Jiaotong University, Gansu Province, China

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