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Abstract

A real narrowband noise signal representation in the form of an analytical signal in the Hilbert space is presented in the paper. This analytical signal is illustrated in a variable complex plane as a mark with defined amplitude, phase, pulsation and instantaneous frequency. A block diagram of a broadband product detector in a quadrature system is presented. Measurement results of an autocorrelation function of a noise signal are shown and the application of such solution in a noise radar for precise determination of distance changes as well as velocities of these changes are also presented. Conclusions and future plans for applications of the presented detection technique in broadband noise radars bring the paper to an end.
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Authors and Affiliations

Waldemar Susek
Bronisław Stec
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Abstract

Due to insufficient operation efficiency, the studied treatment plant has undergone modernization. The aim of this study was to assess whether this modernization improved quality of the STP effluent and water quality in the receiver. The research period of fifty months covered time before and after the modernization. Samples were collected in four sites – upstream and downstream of the STP and by the sewage discharge. Electrolytic conductivity, water temperature and pH were measured onsite. Chemical analyzes were based on ion chromatography and determined the concentration of NH4+, NO3-, NO2-, PO43-, TDS. Microbiological analysis comprised serial dilutions to assess the number of mesophilic and psychrophilic bacteria and membrane filtration to enumerate E. faecalis, total and fecal coliforms as well as total and fecal E. coli. Values of most analyzed parameters did not improve after the modernization, or improved for a very short period of time (NH4+), while some of them even increased, such as PO43-, total and thermotolerant coliforms and E. coli. The maximum value of thermotolerant E. coli reached nearly 7 million CFU/100 ml and was observed after modernization. Also at the sites situated downstream of the STP some of analyzed parameters increased. The conducted modernization did not improve the quality of treated sewage and even a further deterioration was observed. It could have been a result of rapidly growing number of tourists visiting the studied area, thus generating large amounts of sewage causing STP overload coupled with poor water and wastewater management. Significant percentage of unregistered tourists hinders proper assessment of the STP target efficiency.

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Authors and Affiliations

Anna Lenart-Boroń
Anna Bojarczuk
Łukasz Jelonkiewicz
Mirosław Żelazny
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Abstract

The significance of the famous Shannon's publication "A mathematical theory of communication" is discussed. The author states that this theory was a breakthrough for the times it was created. The present-day communications is so highly developed, that some old maxims should be up-dated, particularly the definition of the lower bound of signal reception. The author claims that this bound is no longer a constant value, ln(2), as the Shannon's theory states, but depends on many factors such, as the ratio of bandwidth-to-information transmission rate, the class of a receiver (adaptive, cognitive, MIMO1), the kind of reception system (on-line or off-line), and - of course - on the characteristics of noise, including entropy. Then, an absolute limit (Eb/N0)abs = 0 is suggested. An example of an advanced adaptive system approaching this bound is given.

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Authors and Affiliations

J. Pawelec
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Abstract

Satellite-based positioning, which started being developed in the mid-1960s for military purposes, is now used in almost every area. For the studies single and/or double frequency receivers are used. The cost of a receiver and antenna couple that have capable of high coordinate accuracies ranges from $3000 to $15000. With the production of Original Equipment Manufacturer (OEM) receivers, the cost of satellite-based location determination decreases to approximately one in 10 for the civilian user compared to the operations performed with geodetic receivers and antennas. However, although these receivers collect data in multi-Global Navigation Satellite System (GNSS) and frequencies, the accuracy of the coordinate values estimated is not as high as geodetic receivers and antennas. Therefore, it is necessary to carry out an accuracy study to obtain information about which studies can be used in. In this study, measurements were made at the UZEL point located on the roof of the Yıldız Technical University Geomatics Engineering Department by using the ZED-F9P-02B OEM multi GNSS receiver and ANN-MB L1/L2 multi-band GNSS patch antenna. The performance of the test results has been examined by comparing the results from CSRS(Canadian Spatial Reference System)-PPP with the coordinates of the UZEL point. As a result of the comparison, the difference between the coordinate determined with collected 3.5 hr data and the coordinates of the UZEL point has been determined as – 1.4 cm, 2.8 cm, and 9.3 cm in the East, North, and Height directions, respectively
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Authors and Affiliations

Mustafa Fahri Karabulut
1
ORCID: ORCID
Nedim Onur Aykut
1
ORCID: ORCID
Burak Akpınar
1
ORCID: ORCID
Güldane Oku Topal
1
ORCID: ORCID
Zübeyir Bilal Çakmak
1
ORCID: ORCID
Bilge Doran
1
ORCID: ORCID
Ahmet Anıl Dindar
2
ORCID: ORCID
Cemal Özer Yiğit
2
ORCID: ORCID
Mert Bezcioğlu
2
ORCID: ORCID
Anıl Zafer
2
ORCID: ORCID

  1. Yildiz Technical University, Istanbul, Turkey
  2. Gebze Technical University, Gebze, Turkey
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Abstract

No adequate reaction has been observed of the decreased contaminant loads discharged by Łódź, particularly the loads of phosphorus, on its concentration in the Ner River. That’s why the im-pact of sediment on phosphorus content in the water was evaluated. Not only was the amount of phosphorus taken under consideration but also the equilibrium phosphate concentration (EPCo). The meaning of EPCo is that any phosphate concentration in the water below this value will lead to phos-phorus release from sediments. Performed study shows that in the Puczniew cross-section EPCo is higher then phosphorus concentration in water, thus with mean concentration of PO4 equal to 9.5 mg PO4·dm–3 phosphorus could be released from sediments. This concentration in Lutomiersk cross-section, however, equals 1.2 mg PO4·dm–3.

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Authors and Affiliations

Józef Mosiej
Hubert Komorowski
Agnieszka Karczmarczyk
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Abstract

A double balanced passive mixer-based receiver operating in the 3-5 GHz UWB for medical applications is described in this paper. The receiver front-end circuit is composed of an inductorless low noise amplifier (LNA) followed by a fully differential voltage-driven double-balanced passive mixer. A duty cycle of 25% was chosen to eliminate overlap between LO signals, thereby improving receiver linearity. The LNA realizes a gain of 25.3 dB and a noise figure of 2.9 dB. The proposed receiver achieves an IIP3 of 3.14 dBm, an IIP2 of 17.5 dBm and an input return loss (S11) below -12.5dB. Designed in 0.18μm CMOS technology, the proposed mixer consumes 0.72pW from a 1.8V power supply. The designed receiver demonstrated a good ports isolation performance with LO_IF isolation of 60dB and RF_IF isolation of 78dB.
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Authors and Affiliations

Thaar A. Kareem
1
Hatem Trabelsi
1

  1. Systems Integration & Emerging Energies Laboratory, Electrical Engineering Department, National Engineers School of Sfax, University of Sfax, Sfax, Tunisia
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Abstract

In the past it was usual to exert a huge effort in the design, simulation, and the real time implementation of the complicated electronic and communication systems, like GNSS receivers. The complexity of the system algorithms combined with the complexity of the available tools created a system that is difficult to track down for debugging or for redesign. So, the simulation and educational tools was different from the prototyping tools. In this paper the parallel search acquisition phase of a GPS receiver was simulated and implemented on FPGA using the same platform and through a graphical programming language. So this paper introduces the fruit of integrating the prototyping tools with the simulation tools as a single platform through which the complicated electronic systems can be simulated and prototyped.

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Authors and Affiliations

Mohamed Ibrahiem El Hawary
Gihan Gomah Hamza
Abdelhalim Zekry
Ibrahiem Mohamed Motawie
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Abstract

The paper analyzes the operation of innovative composite measurement instrumentation for spontaneous electromagnetic emission. The designed receiver measures and records both components of the EM field emitted by rocks subjected to increased mechanical stress. The range of signals transmitted by the receiver system and its dynamics were determined. A receiver was used to observe electromagnetic signals generated during a hard coal sample crushing in laboratory conditions. Test results confirmed the high dynamic range of the system at 98 dB and the ability to observe signals over a range of frequencies up to 50 kHz. The experimental results confirm the signal bandwidth characteristic of coal mine EM field emission obtained in earlier studies. The constructed autonomous receiver can be used in mine workings as a complementary warning system for emerging mine hazards.
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Bibliography

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Authors and Affiliations

Remigiusz Mydlikowski
1
ORCID: ORCID
Krzysztof Maniak
2
ORCID: ORCID

  1. Wroclaw University of Science and Technology, Faculty of Electronics, Photonics and Microsystems, ul. Janiszewskiego 11/17, 50-372 Wrocław, Poland
  2. National Institute of Telecommunications, ul. Szachowa 1, 04-894 Warsaw, Poland
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Abstract

The topic „The Bible and Christian Morality" was thoroughly studied by the Papal Biblical Commission. The article's author presents the originality of this concept. He proves why we ought to speak of „revealed morality" and not about Gospel ethics, the writings of St. Paul or OT and NT ethics. Morality - as opposed to ethics - does not rely on freely accepted initial assumptions, but is man's response to the gifts received from God: creation, covenant and fullness of revelation in Christ. It brings to light the criteria resulting from the Bible itself, which contemporary Christians should apply when dealing with problems that contemporary sciences, techniques and culture present, but about which the inspired books do not directly speak of. He stresses that the Bible itself, revealing what is unique and which does not undergo discussion, at the same time calls the faithful of God to dialogue with the world in which we live, particularly with believers of other religions.

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Authors and Affiliations

Ks. Henryk Witczyk
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Abstract

The paper presents verification of a peak detection method cooperating with infrared radiation detector module applications. The work has been divided into parts including SPICE simulations and presentation of results obtained with the constructed prototype. The design of the peak detector dedicated to applications with very short pulses requires a different approach than that for standard solutions. It is mainly caused due to the ratio of pulse width and time period. In the described application this ratio is less than 10%. The paper shows testing of an analogue circuit which is capable to be inserted in these applications.

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Authors and Affiliations

Krzysztof Achtenberg
Janusz Mikołajczyk
Dariusz Szabra
Artur Prokopiuk
Zbigniew Bielecki
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Abstract

Due to the extensive use of nonlinear power consumers, there is currently an urgent problem of high harmonic content in power supply networks. The paper provides experimental investigations and a study of the nature of the change in the main harmonic components of the current in the neutral working wire of a three-phase four-wire network with a voltage of 0.38 kV. The purpose of this study is to compare the load readings on the amplitude-phase-frequency characteristics of the current in the neutral working wire of the 0.38 kV network with the linear and non-linear load. To study the effect of load changes on the amplitude-phase-frequency characteristics of currents in the linear and zero working wires at the input of the load node, measurements were carried out by certified electrical measuring instruments. The analysis of the results obtained for the load node whose power was formed mainly by a lighting system with fluorescent and LED lamps and a system of office electrical receivers (computers, copiers, printers, scanners, etc.) was performed. It can be concluded that a current comparable to the currents of the linear wires of the network flows from the load node with the predominant nonlinear power receivers through the zero-working wire. At the same time, in the zero-working wire of the network, the third harmonic currents prevail over the main frequency currents.
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Bibliography

[1] Golub I., Boloev E., Methods of linear and nonlinear state estimation of distribution network, Proceedings of E3S Web of Conferences, Irkutsk, Russian Federation (2018).
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[9] Corasaniti V.F., Barbieri M.B., Arnera P.L., Valla M.I., Characteristics of the loads in medium voltage networks from the point of view using active filters, in IEEE PES Transmission and Distribution Conference and Exposition, pp. 1–7 (2006).
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[11] Szulborski M., Kolimas Ł., Łapczynski S., Szczęśniak P., Single phase UPS systems loaded with nonlinear circuits: Analysis of topology in the context of electric power quality, Archives of Electrical Engineering, vol. 68, no. 4, pp. 787–802 (2019).
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Authors and Affiliations

Igor V. Yudaev
1
Evgeny V. Rud
2
Mikhail A. Yundin
1
Tamara Z. Ponomarenko
2
Aleksandra M. Isupova
1

  1. Azov-Black Sea Engineering Institute of Don State Agrarian University, Russia
  2. ICPE Energy Institute for Advanced Studies of the PJSC “Kubanenergo”, Russia
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Abstract

In the era of continuous advancement in wireless technologies, path loss, also known as channel attenuation, is a drop in signal strength from the transmitter to the receiver. Path loss modelling is critical in designing fixed and mobile communication systems for various applications. This paper focuses on the received power (dBm) and free space path loss (FSPL) on various distances and frequencies such as 5240 MHz for wireless local area network (WLAN) and frequency such as 2100 MHz for the mobile network such as Celcom. As a result, able to analyze the correspondence between received power (dBm) and distance of each related frequency and the correspondence between FSPL (dB) and distance of each corresponding frequency and able to analyze the effect of obstacle on received power (dBm) and frequency.
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Authors and Affiliations

Kavinesh S Radhakrishna
1
Y.S. Lee
2
K.Y. You
3
K.M. Thiruvarasu
1
S.T. Ng
1

  1. Faculty of Electronic Engineering Technology, Universiti Malaysia Perlis (UniMAP), Perlis, Malaysia
  2. Faculty of Electronic Engineering Technology and Advanced Communication Engineering, Centre of Excellence (CoE), Universiti Malaysia Perlis (UniMAP), Perlis, Malaysia
  3. Faculty of Electrical Engineering, Universiti Teknologi Malaysia, 81310 UTM Skudai, Johor, Malaysia
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Abstract

Data security is one of the prime concerns in wireless networks. PLKG has been emerging as an attractive alternative to traditional cryptographic techniques. PLKG is more computationally efficient than cryptography. Moreover, PLKG using Principal component analysis (PCA) as pre-processing may further save computations. This paper proposes three mechanisms to select components of PCA which are based on Information content, Mean and Histfit. Bit Disagreement Rate (BDR) is compared for each mechanism. Histfit based method is found to be best. Since only two components are supposed to be processed for key generation, it is computationally efficient/ power efficient too.
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Authors and Affiliations

Tapesh Sarsodia
1
Uma Rathore Bhatt
1
Raksha Upadhyay
1
Vijay Bhat
2

  1. Institute of Engineering and Technology, Devi Ahilya University, Indore, India
  2. Sage University, Indore, Madhya Pradesh, India
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Abstract

The performance of free-space optical (FSO) communications that using an optical amplifier (OA) in the scheme of an amplify-received (AR)-relaying has a major drawback in the detection of input signal quality under the effects of turbulence. As an OA is based on a fiber-detection (FD) method to receive and delivers a signal at the amplification process stage, there is an opportunity to implement an optical spatial filter (OSF) to improve the quality of an input signal. In this paper, as the continuation of previous work on the direct-detection, the OSF is applied on the AR-relaying. The novelty proposed in this work is the improvement of FD method where the OSF is designed as the integration of cone reflector, pinhole and multi-mode fiber with an OA. The OSF produces an optical signal, the input of the OA, which minimizes the effects of turbulence, background noise and signal fluctuation. Thus, OA in AR-relaying produces signal output with high power and rise up below threshold level. Additionally, an OSF with a lower pinhole diameter produces the best quality of the signal spectral to be delivered into an EDFA. Through this implementation, the performance of optical relaying on FSO can be significantly improved.
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Authors and Affiliations

Ucuk Darusalam
1 2
Purnomo Sidi Priambodo
3
Fitri Yuli Zulkifli
3
Eko Tjipto Rahardjo
3

  1. Department of Informatics, Faculty of Information and Communications Technology, Universitas Nasional, Jakarta, Indonesia
  2. Universitas Siber Asia, Jakarta, Indonesia
  3. Department of Electrical Engineering, Universitas Indonesia, Depok, Indonesia
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Abstract

In the framework of the 4th International Polar Year Panel “Plate Tectonics and Polar Gateways” the international project “The Dynamic Continental Margin Between the Mid-Atlantic-Ridge System (Mohns Ridge, Knipovich Ridge) and the Bear Island Region” was undertaken in 2007-2008. As a part of this project a new three-component seismic broadband station was installed in September 2007 in the area of the Polish Polar Station Hornsund in Southern Spitsbergen . The new HSPB station has the coordinates: Φ = 77.0019°N, λ = 15.5332°E, H = 11 m a.s.l. During the first years of operation a number of good quality teleseismic events were recorded. This gives the opportunity for a first determination of crustal and mantle structure beneath the station by using receiver function (RF) and SKS splitting techniques. The Moho depth determined using RF is about 32 km beneath HSPB. Significant amplitudes on the transverse components of the RF indicate a shallowly dipping discontinuity (sedimentary-basement) towards the south-west. The fast polarization of SKS phases is near parallel to the border between the continental and the oceanic crust and the Hornsund fault (α = 151.8°). The average time delay dt between “fast” and “slow” directions is 0.68 s, which implies ca. 2% anisotropy in a 100- 200 km thick layer in the mantle.

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Authors and Affiliations

Monika Wilde-Piórko
Marek Grad
Paweł Wiejacz
Johannes Schweitzer

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