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Abstract

The purpose of this article is to present three theses – (1) a cultural one: cyberspace is an advanced technical and cultural creation – it is an embodiment of dreams of numerous creators, inventors and engineers; (2) a technical one: security and cyberspace are inseparable components (hence cybersecurity); (3) and a paranoid one: complete security, if achievable, is not a permanent state (hence cyber(in)security). Cyberspace is conceived as a set of digital techniques used to exchange information but also as a new type of social space, partially virtual, which may constitute a being entirely separated from a physical one. A pivotal date for arising of cyberspace may be considered the year 1968 in which routing in the ARPANET network appeared and so did the first programmable logical controller (PLC). For cyberspace this will be the year 1976 – publishing of the key agreement protocol by Witfield Diffie and Martin Hellman. Development of security is correlated with warfare and armament – the military sector has historically made the most significant investments in this area.

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Authors and Affiliations

Krzysztof Szczypiorski
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Abstract

Backchannel responses (BChs) have been an important research topic in conversation analysis since Yngve (1970) drew a distinction between speech produced by the person holding the turn and talking in the ‘main’ channel, while the listener occupying the ‘back’ channel of the communication. However, much less is known about the acoustic-phonetic characteristics of BChs.
The aim of the present study is twofold: 1. it seeks to provide a general analysis of BChs as a formal group in 10 Hungarian conversations, using a formal, phonetic approach. 2. Additionally, another sub-study was conducted concerning the contextual variability of BChs investigating their change, according to the age of the conversation partner in three-party conversations.
The age of the subject did not significantly affect the frequency and duration of the fieldworker1’s BCh or the other acoustic parameters, however it did make some difference in pause patterns. In contrast, gender-related changes were detected in the fieldworker1’s utterance: having produced more BChs when talking to older women. This may be explained by the possible intimacy in female conversations as well as by the influence of politeness. The results might offer new insights of the conversation’s structure with regard to their age and gender.
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Authors and Affiliations

Valéria Krepsz
1 2
Viktória Horváth
1
Ágnes Hámori
1
Dorottya Gyarmathy
1
Csilla Ilona Dér
3

  1. Hungarian Research Centre for Linguistics
  2. Humboldt-Universität zu Berlin
  3. Károli Gáspár University of the Reformed Church in Hungary
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Abstract

Analog-to-Digital Converters (ADCs) are devices that transform analog signals into digital signals and are used in various applications such as audio recording, data acquisition, and measurement systems [1]. Prior to the development of actual chip, there is a need for prototyping, testing and verifying the performance of ADCs in different scenarios. Analog macros cannot be tested on an FPGA. In order to ensure the macros function properly, the emulation of the ADC is done first. This is a digital module and can be designed in System Verilog. This paper demonstrates the design of the module on FPGA for Analog to Digital Converter (ADC) emulation. The emulation is done specific to the ADC macro which has programmable resolutions of 12/10/8/6 bit.
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Authors and Affiliations

Huma Tabassum
1
Krishna Prathik BV
1
Sujatha S Hiremath
1

  1. RV College of Engineering, India
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Abstract

This article discusses the issue of hypermodernity, which was studied as part of the research project Poles in the World of Late Capitalism. The article presents biographical models of hypermodernity and strategies of coping with hypermodern ideology, that is, cyclothymias, conversions, and hypermodern episodes.

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Authors and Affiliations

Kamila Biały
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Abstract

The aim of the study was to evaluate the biochemical possibilities of converting waste lignocellulosic biomass to second generation bioethanol. Three substrates were used in the research: barley straw, rye straw and triticale straw. In the first stage of the research bacterial strains capable of converting waste biomass to produce sugars used to produce energy-useful ethanol were selected. Of the eight strains isolated the three with the highest potential were selected on the basis of activity index value. The raw materials were subjected to enzymatic hydrolysis using the simultaneous saccharifi cation and fermentation method (SSF process). Based on the conducted research, it was found that the examined waste biomass is suitable for the production of cellulosic bioethanol. As a result of distillation 10% and 15% (v/v) ethanol was obtained, depending on the strain and the type of raw material. It was demonstrated that the bacterial strain had a greater impact on the effectiveness of the process than the type of straw used.
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Authors and Affiliations

Małgorzata Hawrot-Paw
1
Adam Koniuszy
1
Grzegorz Zając
2
Joanna Szyszlak-Bargłowicz
2
Julia Jaklewicz
1

  1. West Pomeranian University of Technology, Department of Renewable Energy Engineering, Poland
  2. University Of Life Sciences in Lublin, Department of Power Engineering and Transportation, Poland
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Abstract

Phosphating is the process of depositing, by conversion, a layer of insoluble phosphate compounds, on the metal’s surface. Although phosphate coatings have been studied since the early nineteenth century, they are not only still being studied, but are an area of interest due to their many applications. The advantages of these types of coatings are well known, such as the low cost of the deposition process, the improvement of corrosion resistance properties, and the improvement of wear resistance and adhesion of further deposited layers such as paint. All this, leads to studies on the constant improvement of the properties of the phosphate coating, by modifying the parameters of the phosphating process, as well as by modifying/replacing the substances used in the phosphating solutions with “environmentally friendly” solutions. Also due to these advantages, several researchers are studying the possibility of using phosphate coatings in fields such as civil engineering or medicine (biomaterials coatings). This paper aims to present some essential aspects of phosphating and to bring to the fore the latest research on “eco-friendly” phosphating solutions and the possibility of using the phosphating process in other fields, such as the medical field. Also, the paper aims to discuss the possibility of eliminating/reducing the harmful effect that the use of phosphating has on the environment.
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Authors and Affiliations

D.-P. Burduhos-Nergis
1
ORCID: ORCID
A.V. Sandu
1
ORCID: ORCID
D.D. Burduhos-Nergis
1
ORCID: ORCID
P. Vizureanu
1
ORCID: ORCID
C. Bejinariu
1
ORCID: ORCID

  1. “Gheorghe Asachi” Technical University of Iasi, Faculty of Materials Science and Engineering, 41 “D. Mangeron” Street, 700050, Iasi, Romania
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Abstract

The aim of this article is to assess the potential of converting gasoline-powered passenger cars into electric vehicles in Poland. Based on the available literature data, the vehicle structure was classified using the following criteria: vehicle age, engine capacity, car segment, type of fuel used, and curb weight. The average fuel and electric energy consumption values per vehicle before and after conversion were determined using specially developed statistical models. The conversion and operation costs of a conventionally fueled vehicle and an electric vehicle (after conversion) were estimated using a stochastic simulation model employing probability density distributions of vehicle parameters and the Monte Carlo method. Vehicle parameters were estimated to reflect the real structure of passenger cars in Poland. The estimated costs of converting a gasoline-powered vehicle to an electric vehicle (including the purchase and installation of an electric motor and battery) and its subsequent operating costs enabled the assessment of the economic efficiency of the car conversion process. The potential for converting gasoline-powered cars to electric vehicles was estimated by comparing the operating costs of the vehicle before and after conversion, taking into account the costs of the conversion itself. The potential of the studied conversion process amounted to 535,000 vehicles, which would generate an annual electricity demand of 1,746.36 GWh with electricity prices of 0.6 PLN/kWh. The conversion is economically viable mainly in passenger cars with a spark engine (more than 90% of cases).
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Authors and Affiliations

Dominik Kryzia
1
ORCID: ORCID
Katarzyna Kryzia
2
ORCID: ORCID

  1. The Mineral and Energy Economy Research Institute of the Polish Academy of Sciences, Kraków, Poland
  2. Faculty of Civil Engineering and Resource Management, AGH University of Science and Technology, Poland
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Abstract

Wave motion in pipe bends is much more complicated than that in straight pipes, thereby changing considerably the propagation characteristics of guided waves in pipes with bends. Therefore, a better understanding of how guided waves propagate in pipe bends is essential for inspecting pipelines with bends. The interaction between a pipe bend and the most used non-dispersive torsional mode at low frequency in a small-bore pipe is studied in this paper. Experiments are conducted on a magnetostrictive system, and it is observed that T(0,1) bend reflections and mode conversions from T(0,1) to F(1,1) and F(2,1) occur in the pipe bend. The magnitude of the T(0,1) bend reflections increases with increasing propagation distance and excitation frequency. The amplitude of the mode-converted signals also increases with increasing propagation distance, but it decreases with increasing excitation frequency. Because of their longer bent path, the test signals for a pipe bend with a bending angle of 180X are much more complicated than those for one with a bending angle of 90X. Therefore, it is even more difficult to scan a bent pipe with a large bending angle. The present findings provide some insights into how guided waves behave in pipe bends, and they generalize the application of guided-wave inspection in pipelines.

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Authors and Affiliations

Wenjun Wu
Junhua Wang
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Abstract

The neutral point clamped (NPC) three-level inverter is widely used in highvoltage and high-power applications. However, neutral point voltage oscillation (NPVO) and common-mode voltage (CMV) problems exist in the NPC three-level inverter. In this paper, an improved virtual space vector modulation (VSVM) is proposed based on the reconstruction of a virtual small vector and a virtual medium vector. Compared with the traditional VSVM, an improved VSVM can effectively reduce the CMV. On this basis, a vector conversion method is proposed to further reduce the NPVO in the whole range. Simulation results verify the effectiveness and superiority of the improved VSVM.
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Bibliography

[1] Zhang X.,Wu X., Geng C., Ping X., Chen S., Zhang H., An Improved Simplified PWM for Three-Level Neutral Point Clamped Inverter Based on Two-Level Common-Mode Voltage Reduction PWM, IEEE Trans. Power Electronics, vol. 35, no. 10, pp. 11143–11154 (2020).
[2] Kaniewski J.Z., Power flow controller based on bipolar direct PWM AC/AC converter operation with active load, Archives of Electrical Engineering, vol. 68, no. 2, pp. 341–356 (2019).
[3] Beniwal N., Townsend C., Farivar G., Pou J., Ceballos S., Tafti H., Band-Limited Three-Level Modulation for Balancing Capacitor Voltages in Neutral-Point-Clamped Converters, IEEE Trans. Power Electronics, vol. 35, no. 9, pp. 9737–9752 (2020).
[4] Pham K., Nguyen N., A Reduced Common-Mode-Voltage Pulsewidth Modulation Method With Output Harmonic Distortion Minimization for Three-Level Neutral-Point-Clamped Inverters, IEEE Trans. Power Electronics, vol. 35, no. 7, pp. 6944–6962 (2020).
[5] Li C., Yang T., Kulsangcharoen P., Lo Calzo G., Bozhko S., Gerada C., Wheeler P., A Modified Neutral-Point Balancing Space Vector Modulation for Three-Level Neutral Point Clamped Converters in High Speed Drives, IEEE Trans. Ind. Electronics, vol. 66, no. 2, pp. 910–921 (2019).
[6] Jordi Z., Josep P., Salvador C., A Comprehensive Study of a Hybrid Modulation Technique for the Neutral-Point-Clamped Converter, IEEE Trans. Ind. Electronics, vol. 56, no. 2, pp. 294–304 (2009).
[7] Nguyen T.K.T., Nguyen N.-V., Prasad N.R., Eliminated common mode voltage pulse width modulation to reduce output current ripple for multilevel inverters, IEEE Trans. Power Electronics, vol. 31, no. 8, pp. 5952–5966 (2016).
[8] Lee J.S., Lee K.B., Time-Offset Injection Method for Neutral-Point AC Ripple Voltage Reduction in a Three-Level Inverter, IEEE Trans. Power Electronics, vol. 31, no. 3, pp. 1931–1941 (2016).
[9] McGrath B.P., Holmes D.G., Meynard T., Reduced PWM harmonic distortion for multilevel inverters operating over a wide modulation range, IEEE Trans. Power Electronics, vol. 21, no. 4, pp. 941–949 (2006).
[10] Chen J., He Y., Hasan S.U., Liu J., A comprehensive study on equivalent modulation waveforms of the SVM sequence for three-level inverters, IEEE Trans. Power Electronics, vol. 30, no. 12, pp. 7149–7158 (2015).
[11] Choi U.M., Lee J.S., Lee K.B., New modulation strategy to balance the neutral-point voltage for threelevel neutral-clamped inverter systems, IEEE Trans. Energy Conversion, vol. 29, no. 1, pp. 91–100 (2014). 218 Junlong Fang et al. Arch. Elect. Eng.
[12] Choi U.M., Lee K.B., Blaabjerg F., Method to minimize the low frequency neutral-point voltage oscillations with time-offset injection for neutral-point-clamped inverters, IEEE Trans. Ind. Appl., vol. 51, no. 2, pp. 1678–1691 (2015).
[13] Busquets-Monge S., Bordonau J., Boroyevich D., Somavilla S., The nearest three virtual space vector PWM – A modulation for the comprehensive neutral-point balancing in the three-level NPC inverter, IEEE Power Electron. Lett., vol. 2, no. 1, pp. 11–15 (2004).
[14] Xiang C.Q., Shu C., Han D., Improved Virtual Space Vector Modulation for Three-Level Neutral- Point-Clamped Converter with Feedback of Neutral-Point Voltage, IEEE Trans. Power Electronics, vol. 33, no. 6, pp. 5452–5464 (2018).
[15] Mukherjee S., Giri S., Banerjee S., An Improved Adjustable Modulation Strategy for Three-Level NPC Inverters Considering Dynamic Loading Applications, IEEE Trans. Ind. Electronics, vol. 65, no. 10, pp. 3915–3925 (2018).
[16] Yonglong Zhang, Yuejun An, Guangyu Wang, Xiangling Kong, Multi motor neural PID relative coupling speed synchronous control, Archives of Electrical Engineering, vol. 69, no. 1, pp. 57–68 (2020).
[17] Peng S., Zhang G., Qin C., Zhou Z., Gu X., Xia C., MPTC of NP-clamped three-level inverter-fed permanent-magnet synchronous motor system for NP potential imbalance suppression, IET Electric Power Applications, vol. 14, no. 4, pp. 658–667 (2020).
[18] Qin C., Zhang C., Chen A., Xing X., A space vector modulation scheme of the quasi-Z-source threelevel T-type inverter for common-mode voltage reduction, vol. 65, iss. 10, pp. 8340–8350 (2018).
[19] Pham K., Nguyen N., A Reduced Common-Mode-Voltage Pulsewidth Modulation Method with Output Harmonic Distortion Minimization for Three-Level Neutral-Point-Clamped Inverters, IEEE Trans. Ind. Electronics, vol. 35, no. 7, pp. 6944–6962 (2020).
[20] Xu X., Zheng Z., Wang K., Yang B., Li Y., A Comprehensive Study of Common Mode Voltage Reduction and Neutral Point Potential Balance for a Back-to-Back Three-Level NPC Converter, IEEE Trans. Power Electronics, vol. 35, no. 8, pp. 7910–7920 (2020).
[21] Jiang W., Wang P., Ma M., A Novel Virtual Space Vector Modulation with Reduced Common-Mode Voltage and Eliminated Neutral Point Voltage Oscillation for Neutral Point Clamped Three-Level Inverter, IEEE Trans. Ind. Electronics, vol. 67, no. 2, pp. 884–894 (2020).
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Authors and Affiliations

Junlong Fang
1
ORCID: ORCID
Guangya Wang
1
Ran Li
1
Siyuan Liu
1
Shuyu Wang
1

  1. School of Electricity and Information, Northeast Agricultural University, China
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Abstract

Dye-sensitized solar cells (DSSCs) were prepared using various food dyes. Food dyes are economically superior to organometallic dyes since they are nontoxic and inexpensive. The spectrophotometric evaluation of chosen food dyes in solution and on a TiO2 substrate show that the dyes form J-aggregation on the photoelectrode substrate. Oxidation of potential measurements for used food dyes ensured an energetically permissible and thermodynamically favorable charge transfer throughout the continuous cycle of a photo-electric conversion. The performance of dye-sensitized solar cells based on food dyes was studied. The results illustrate that the dye containing carboxylic acid and sulfonic acid as the acceptor group gave the maximum conversion efficiency 4.20%.

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Authors and Affiliations

M. Hosseinnezhad
S. Rouhani
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Abstract

This work presents a theoretical study for the distribution of nanocomposite structure of plasmonic thin-film solar cells through the absorber layers. It can be reduced the material consumption and the cost of solar cell. Adding nanometallic fillers in the absorber layer has been improved optical, electrical characteristics and efficiency of traditional thin film solar cells (ITO /CdS/PbS/Al and SnO2/CdS/CdTe/Cu) models that using sub micro absorber layer. Also, this paper explains analysis of J-V, P-V and external quantum efficiency characteristics for nanocomposites thin film solar cell performance. Also, this paper presents the effect of increasing the concentration of nanofillers on the absorption, energy band gap and electron-hole generation rate of absorber layers and the effect of volume fraction on the energy conversion efficiency, fill factor, space charge region of the nanocomposites solar cells.

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Authors and Affiliations

Ahmed Thabet
Safaa Abdelhady
A.A. Ebnalwaled
A.A. Ibrahim
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Abstract

Communication with authorities belongs to a field of research with a long and intensive research tradition. The present paper focuses on the process of understanding in oral institutional communication. It will present some mechanisms by which common understanding is achieved by using different resources. In contrast to the numerous papers dealing with written institutional communication, little work has been carried out on conversations in the administration. Based on Becker-Mrotzek’s (1999, 2001) classification of oral institutional communication into three different types: discourse on con-sultation, objection and application, the present paper focuses on data collection interviews or application discourses (Ger. Datenerhebungsgespräche), which form “the major part of citizen-administration-discourses” (Becker-Mrotzek 1999: 1399). Despite the frequency of these types of discourse, they are the subject of remarkably few studies.

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Authors and Affiliations

Anna Khalizova
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Abstract

Adjustable-width pulse signals are widely used in systems such as test equipment for hold time, response time and radar testing. In this study, we proposed a pulse generation method based on virtual sampling with ultra-high pulse width resolution. In the proposed method, the sampling rate of a digital-to-analogue converter (DAC) was adjusted to considerably improve pulse width resolution. First, the sampling rate was matched with the target pulse width resolution to digitally sample the ideal signal and generate digital waveform sampling points. Next, the signal bandwidth of the DAC was matched using a low-pass digital filter. Finally, the waveform sampling points were downsampled using an integer factor and output after digital-to-analogue conversion. The waveform pulse width information generated by high-frequency digital sampling was passed step by step and retained in the final output analogue signal. A DAC with a sampling rate of 1.25 GSa/s was used, and the pulse width resolution of the pulse signal was 0.1 ns. Theoretically, a sampling rate of 10 GSa/s is required to achieve 0.1 ns resolution. This method is simple, has a low cost, and exhibits excellent performance.
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Authors and Affiliations

Hanglin Liu
1
Zaiming Fu
1
Dexuan Kong
1
Houjun Wang
1
Yindong Xiao
1

  1. University of Electronic Science and Technology of China, School of Automation Engineering, Chengdu 611731, China
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Abstract

The article presents the developed IT solutions supporting the material and technological conversion process in terms of the possibility of using the casting technology of selected alloys to produce products previously manufactured with the use of other methods and materials. The solutions are based on artificial intelligence, machine learning and statistical methods. The prototype module of the information and decision-making system allows for a preliminary assessment of the feasibility of this type of procedure. Currently, the selection of the method of manufacturing a product is based on the knowledge and experience of the technologist and constructor. In the described approach, this process is supported by the proprietary module of the information and decision-making system, which, based on the accumulated knowledge, allows for an initial assessment of the feasibility of a selected element in a given technology. It allows taking into account a large number of intuitive factors, as well as recording expert knowledge with the use of formal languages. Additionally, the possibility of searching for and collecting data on innovative solutions, supplying the knowledge base, should be taken into account. The developed and applied models should allow for the effective use and representation of knowledge expressed in linguistic form. In this solution, it is important to use methods that support the selection of parameters for the production of casting. The type, number and characteristics of data have an impact on the effectiveness of solutions in terms of classification and prediction of data and the relationships detected.
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Authors and Affiliations

D. Wilk-Kołodziejczyk
1 2
ORCID: ORCID
K. Jaśkowiec
2
ORCID: ORCID
A. Bitka
2
ORCID: ORCID
Z. Pirowski
2
ORCID: ORCID
M. Grudzień-Rakoczy
2
ORCID: ORCID
K. Chrzan
2
ORCID: ORCID
M. Małysza
2
ORCID: ORCID
M. Doroszewski
1
ORCID: ORCID

  1. AGH University of Science and Technology, Faculty of Metals Engineering and Industrial Computer Science, Al. Mickiewicza 30, 30-059 Kraków, Poland
  2. Centre of Casting Technology, The Łukasiewicz Research Network – Cracow Technology Institute, Poland
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Abstract

The authors of this article were guided by the desire to show the profitability of using renewable energy sources and to facilitate decisions for future investors as to their choice. The article classifies energy sources and methods for converting renewable energy sources (RES) and presents a technical comparison of two electricity supply systems: a photovoltaic system and a household wind farm for a selected building. A residential, single-family building, inhabited by a family of three, was adopted for analysis. Photovoltaics, the use of solar radiation energy to produce electricity, is classified next to wind farms as the most dynamically developing renewable energy technology. When analysing in terms of technology renewable conversion methods that provide us with electricity, the better installation is the photovoltaic installation. By analysing the cost of renewable energy conversion technologies that provide us with electricity, the photovoltaic system becomes more beneficial, because with a similar investment price we get a much shorter payback period than in the case of a backyard wind power station.
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Authors and Affiliations

Wojciech Drozd
1
ORCID: ORCID
Marcin Kowalik
1
ORCID: ORCID

  1. Department of Construction Management, Tadeusz Kościuszko Cracow University of Technology, Warszawska 24 St., 31-155 Kraków, Poland
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Abstract

Tunnel construction survey must be necessary to be very quick so that the results can be known as soon as possible. This aim can be achieved through the intelligent positioning method of tunnel excavation face. In this study, the plane parameters of the tunnel cross-section were transformed into the coordinates of the points on the cross-section to realize the automatic transformation of graphic data. According to the theoretical calculation of the lofting point accuracy, the appropriate measurement control network level and measurement accuracy and the appropriate measurement instruments were selected. The fast and intelligent positioning and setting out of tunnel excavation face was realized base on the technology of data communication between computer and measuring instruments. The intelligent positioning method of tunnel excavation face could greatly reduce the time of measurement and positioning, speed up the project progress, reduce the project risk, shorten the construction period and reduce the project cost.
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Bibliography

[1] K. Rabensteiner, “Automated surveying speeds construction”, Tunnels & Tunnelling, 1996, vol. 28, no. 1, pp. 40–41.
[2] H.E. Bin, “Application of CASIO Measurement Program Assisted by Total Station in Survey of Tunnel Cross-Section”, Tunnel Construction, 2009, vol. 29, no. 1, pp. 120–122.
[3] Z. Lei, “Application of Total Station ’s Surrounding Measurement Function in Highway Survey and Design”, Peak Data Science, 2017, vol. 6, no. 4, pp. 105–107.
[4] L.F. Geng, “Analysis of mechanical properties of full section excavation of single arch four-lane highway tunnel”, Shanxi Architecture, 2009, vol. 2.
[5] Y.H. Deng, “Determination of full section excavation boundary of transition curve tunnel”, Mine Surveying, 2004, vol. 2004, no. 2, pp. 34–36.
[6] W.W. Yan, “Application of CASIO Series Programming Calculator in the Measurement of Tunnel Sections”, Shanxi ence and Technology, 2011, vol. 26, no. 4, pp. 123–124.
[7] W.B. Luo, “The realization of real-time communication between mobile intelligent equipment and total station under net environment”, Surveying and mapping equipment, 2007, vol. 9, no. 4, pp. 42–43.
[8] C.X. Niu, “Construction Survey of Tanba No. 4 Spiral Tunnel on Xiaohe-Ankang Highway”, Tunnel Construction, 2014, vol. 34, no. 2, pp. 163–166, DOI: 10.3973/j.issn.1672-741X.2014.02.013.
[9] L.H. Luo, S.L. Wei, “Application of Surveying Robot in Pipe Jacking Crossing Subway Tunnel Project”, Jiangsu Construction, 2018, vol. 2018, no. 6, pp. 65–66.
[10] W. He, C. Song, B. Du, “Chinese Longest Sea-crossing Metro Tunnel: Wuyuan Bay Station-Liuwudian Station Section of Xiamen Metro Line 3”, Tunnel Construction, 2018, vol. 38, no. 3, pp. 501–505.
[11] Y.X. Hu, Y. Yue, H.D. Zhang, et al., “Application of Gyroscope in Directional Measurement of Long Distance Cross Sea Metro Tunnel”, Urban Geotechnical Investigation & Surveying, 2019, vol. 2019, no. 6, pp. 172–175.
[12] Y. Zhou, S. Wang, M. Xi, et al., “Railway Tunnel Clearance Inspection Method Based on 3D Point Cloud from Mobile Laser Scanning”, Sensors, 2017, vol. 17, no. 9, DOI: 10.3390/s17092055.
[13] W.Wei, “3D Laser scanning technique is applied to the measurement of tunnel section deformation”, Beijing Surveying and Mapping, 2020, vol. 34, no. 4, pp. 561–565.
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Authors and Affiliations

Jiesheng Zhang
1
ORCID: ORCID
Yongzheng Qi
2
ORCID: ORCID

  1. The First Engineering Co., LTD. of CTCE Group, No. 434 Fuyang North Road, Hefei 230041, China
  2. Jiangsu University of Science and Technology, School of Civil Engineering and Architecture, No. 2 Mengxi Road, Zhenjiang 212003, China
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Abstract

The article presents the issues related to ecological security of the Baltic Sea. The issue was taken from the perspective of Poland as one of the Baltic States, and also as a Member State of the European Union. The authors discussed the mechanisms and legal instruments which are crucial for the ecological security of the Baltic Sea (i.e. Helsinki Convention of 1974, or Agenda 21 for the Baltic Sea Region “Baltic 21”). The importance of cross-border cooperation has also been emphasized as an essential element of the security policy in the Baltic Sea area. The article also indicated threats to the protection of Baltic waters, among others, eutrophication.

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Authors and Affiliations

Janina Ciechanowicz-McLean
ORCID: ORCID
Paulina Bielawska-Srock
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Abstract

The paper presents a method of determining the efficiency of the slewing drive system applied in tower cranes. An algorithm for the proper selection of a permanent magnet synchronous motor (PMSM) for crane applications is presented. In the first stage of our research the proper PMSM was proposed on the basis of the simulation calculation. Next, the PM motor was examined on a special test bench. The experimental setup allows determining major electrical and mechanical parameters of the motor drive system. The applied slewing system consists of: an inverter, gear, cable drum and a permanent magnet motor. The performance and efficiency of the system were experimentally determined. Selected results of the experimental measurement are presented and discussed.
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Bibliography

[1] Gansen A.U., Chokkalingam L.N., Self-start synchronous reluctance motor new rotor designs and its performance characteristic, International Transaction on Electrical Energy Systems, vol. 29, no. 11, pp. 1–22 (2019).
[2] Resa J., Cortes D., Marquez-Rubio J.F., Navarro D., Reduction of induction motor energy consumption via variable velocity and flux references, Electronics, vol. 8, no. 740, pp. 1–14 (2019).
[3] Belmans R., Bisschots F., Trimmer R., Practical design considerations for braking problems in overhead crane drives, Annual Meetings of IEEE Industry Applications Society – IAS, vol. 1, pp. 473–479 (1993).
[4] Baranski M., FE analysis of coupled electromagnetic-thermal phenomena in the squirrel cage motor working at hight ambient temperature, COMPEL, vol. 38, no. 4, pp. 1120–1132 (2019).
[5] Kometani H., Sakabe S., Nakanishi K., 3-D electro-magnetic analyses of a cage induction motor with rotor skew, IEEE Transactions on Energy Conversion, vol. 11, no. 2, pp. 331–337 (1996).
[6] Torrent M., Perat J.I., Jimenez J.A., Permanent magnet synchronous motor with different rotor structures for traction motor in high speed trains, Energies, vol. 11, no. 1549, pp. 1–17 (2018).
[7] Knypinski Ł., Nowak L., Demenko A., Optimization of the synchronous motor with hybrid permanent magnet excitation system, COMPEL, 2015, vol. 34, no. 2, pp. 448–455 (2015).
[8] Zawilak T., Influence of rotor’s cage resistance on demagnetization process in the line start permanent magnet synchronous motor, Archives of Electrical Engineering, vol. 69, no. 2, pp. 249–258 (2020).
[9] Knypinski Ł., Pawełoszek K., Le Manech Y., Optimization of low-power line-start PM motor using gray wolf metaheuristic algorithm, Energies, vol. 13, no. 5, pp. 1–11 (2020).
[10] Dorell D.G., Popescu M., Evans L., Staton D.A., Knight A.M., Comparison of the permanent magnet drive motor with a cage induction motor design for a hybrid electric vehicle, Proceedings of International Power Electronics Conference – ICCE ASIA, pp. 1–6 (2010), DOI: 10.1109/IPEC.2010.5543566.
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Authors and Affiliations

Łukasz Knypiński
1
ORCID: ORCID
Jacek Krupiński
2

  1. Poznan University of Technology, Poland
  2. Krupinski Cranes, Poland
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Abstract

In the paper the analysis of up-conversion (UC) luminescence in 0.5Yb2O3/(0.25-1)Eu2O3 (mol.%) co-doped germanate glass and optical fibre has been investigated. Up-conversion emission of bands at 591, 616, 652, 701 nm to which correspond Eu3+: 5D07F1, 5D07F2, 5D07F3, 5D07F4 transitions, respectively was obtained as a result of cooperative energy transfer between Yb3+ and Eu3+ ions. The highest up-conversion emission (Yb3+ → Eu3+ energy transfer efficiency η = 24%) was obtained in 0.5Yb2O3/0.75Eu2O3 co-doped glass. Comparison of up-conversion and down-conversion luminescence spectra of bulk glass, glass fibre and different length double-clad optical fibre (up to 5 m) showed subtle differences in shape of the spectrum. In comparison to down – conversion emission (λexc = 405 nm) main UC luminescence band is red-shifted by 2 nm and is characterized by 5 nm greater full – width half – maximum (FWHM).

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Authors and Affiliations

M. Kochanowicz
J. Zmojda
T. Ragin
P. Miluski
P. Jelen
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Abstract

Dye sensitized solar cells (DSSCs) based on indigo dyes exhibit suitable conversion efficiency. These organic dyes have been undergone for aggregation. Electron transfer process is reduced due to an aggregation of molecular dyes. Therefore, anti-aggregation agent is commonly utilized in fabrication of DSSCs. In the present study, two anti-aggregation agents namely as 3α,7α-dihydroxy-5β-cholanic acid (cheno) and 3α,7α,12α-trihydroxy-5β-cholanic acid (cholic acid) were added to indigo dye solution in DSSCs in order to determine the photovoltaic parameters such as short circuit photocurrent, open circuit voltage and conversion efficiency of each individual dye in the absence and presence of anti-aggregation agents. The results show that the conversion efficiencies are improved with reduced aggregation. Spectrophotometric evaluations of the indigo dyes in solution and on a TiO2 substrate were carried out in the absence and presence of anti-aggregation agents in order to estimate changes in the status of the dyes in different environments. J-type aggregates on the nano TiO2 are reduced in the presence of anti-aggregation agents.

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Authors and Affiliations

M. Hosseinnezhad
S. Moradian
K. Gharanjig
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Abstract

Erbium-doped lead silicate glass has been investigated for near-infrared emission and up-conversion applications. Near-infrared emission due to 4I13/24I15/2 transition of Er3+ is relatively broad (70.5 nm) and long-lived (3.7 ms). Also, up-conversion luminescence spectra of Er3+ ions in lead silicate glass have been examined as a function of temperature. The relative intensities of luminescence bands corresponding to 2H11/24I15/2 and 4S3/24I15/2 transitions of Er3+ were determined with temperature. The fluorescence intensity ratio and temperature sensitivity were calculated. The maximum sensitivity for Er3+ doped lead silicate glass is close to 26.4 × 10−4 K−1 at T = 590 K.

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Authors and Affiliations

W.A. Pisarski
J. Pisarska
R. Lisiecki
W. Ryba-Romanowski
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Abstract

Clean and cheap device, namely dye-sensitized solar cells (DSSCs) were fabricated using a natural dye extracted from Sambucus ebulus. We prepared five sample solutions with various pH in the extraction process to improve power conversion efficiency. The UV–visible absorption investigation of sample solutions and on photoanode show the dyes from J-type aggregation on a photoanode substrate. Redox properties of all sample solutions certify thermodynamically a charge transfer from excited state to conduction band TiO2. The optical properties of various dye solutions were investigated and results showed darkness and bluish tint effect of dye solutions extracted in basic environment rather than those extracted in acidic condition. Moreover, in comparison to the basic condition, the dye solutions extracted in acidic environment were more saturated and colorimetrically less different from that one which extracted in neutral condition. Photophysical and photoelectrochemical performance of natural extraction dyes have been studied in dye-sensitized solar cell devices. The results show the rather high conversion efficiency of 0.57%, 1.15%, 1.02%, 0.35% and 0.15% of each individual dye extraction, respectively.

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Authors and Affiliations

M. Hosseinnezhad
R. Jafari
K. Gharanjig
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Abstract

Pretreatment is aimed at making lignin structures, which in turn causes decrystallisation and depolymerisation of cellulose. This treatment allows to increase the energy potential of substrates. A properly selected method allows for obtaining larger amounts of biogas with a high content of biomethane. The aim of the study was to analyse selected pretreatment methods (ultrasonic and hydrothermal) for biogas yield, including biomethane, and to demonstrate the effectiveness of obtaining additional electricity and heat from these methods. It was based on the literature data. On basis the study, the following information was obtained: average yield of biogas and biomethane before and after treatment, difference in yield of biogas and biomethane after treatment, and the effect of treatment on the substrate used. Moreover, an estimate was made of the effectiveness of obtaining additional electricity and heat from selected pretreatment methods compared to hard coal. Based on the analysis of the ultrasonic treatment analysis, it was shown that the best result was obtained with the ultrasound treatment of the mixture of wheat straw and cattle manure with the following parameters: frequency 24 kHz, temperature 44.30°C, time 21.23 s. This allowed a 49% increase in biogas production. The use of pretreatment would therefore allow the production of more electricity and heat capable of replacing conventional heat sources such as coal.
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Authors and Affiliations

Milena Piątek
1
ORCID: ORCID
Anna M. Bartkowiak
2
ORCID: ORCID

  1. International Academy of Applied Sciences in Łomża, Faculty of Agricultural Sciences and Engineering and Technology, Studencka St 19, 18-402 Łomża, Poland
  2. Institute of Technology and Life Sciences – National Research Institute, Hrabska Av. 3, Falenty, 05-090 Raszyn, Poland
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Abstract

We present two main ways to precisely create the equivalent transfer function of picosecond time-to-digital converters based on commonly used method with tapped time coding delay lines. The ways consist either in evaluation of the quantization steps boundaries of the delay lines or in summation of numbers of the line quantization steps. The paper contains results of comprehensive analysis of both methods. The advantage and high versatility of the addition method is demonstrated.
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Bibliography

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Authors and Affiliations

Dominik Sondej
1
Rafał Szymanowski
1
Ryszard Szplet
1

  1. Military University of Technology, Faculty of Electronics, Institute of Communication Systems, gen. S. Kaliskiego 2, 00-908 Warsaw 46, Poland

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