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Abstract

The energy efficiency of photovoltaic modules is one of the most important aspects in energetic and economic aspects of the project related to system installations. The efficiency of modules and the electricity produced by photovoltaic conversion in solar modules is affected by many factors, both internal, related to the module structure itself and its technical and external factors related to the energy infrastructure, which includes: cabling, inverters, climate conditions prevailing at the micro-installation location and the orientation and angle of inclination of the solar modules. The installation of photovoltaic modules should be preceded by an energy efficiency analysis, which will help to indicate the optimal solution adapted to the given conditions. The article presents a comparative analysis of the amount of energy produced under real and simulated conditions. Analyzes were made on the basis of research carried out in the Wind and Solar Energy Laboratory located at the AGH University of Science and Technology, data from solar irradiation data-bases and computer software for estimating energy resources. The study examined the correlation of the solar irradiation on the modules and the amount of electricity generated in the photovoltaic module. The electricity produced by the module was compared under real conditions and simulated based on two sources of data. The comparison and analysis of the amount of energy of the module were also made, taking simulated different angles of the module’s inclination into account.

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Authors and Affiliations

Bartosz Soliński
Monika Stopa
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Abstract

The paper presents the results of the energy analysis of the conversion of solar radiation energy into electrical energy in Polish weather conditions. The effect of sunlight and working temperature on the photovoltaic module on its power curve P = f(U) is shown. STC and NOCT conditions are described for which the manufacturers specify the parameters of the photovoltaic modules. The manufacturers of photovoltaic panels should give the PPV = f(E) characteristic for the different values of the operating temperature of the modules. An analysis of the economic efficiency of a photovoltaic power plant investment of 1 MWp taking the current legal regulations for the three variants into account was presented. Variant I – the investor benefits from the support of public aid of operational only, Variant II – the investor benefits from the support of public aid for investment in the amount of PLN 1 million, Variant III – the investor benefits from the support of public aid for investment in the amount of PLN 2 million. For all variants, indicators for assessing the economic effectiveness of the investment and the value of the auction price from the maximum price to the price at which the project loses its profitability are determined.

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Authors and Affiliations

Bartosz Ceran
Radosław Szczerbowski
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Abstract

Wykorzystanie wyników sejsmicznych badań offsetowych do interpretacji złożowej jest powszechnie stosowane w poszukiwaniach złóż węglowodorów. Podstawowa interpretacja ilościowa parametrów związanych z właściwościami złożowymi oparta jest na analizach zmian amplitudy z offsetem (AVO). W tym wypadku analizowana jest amplituda sygnału odbitego od stropu złoża. Efekty anomalne obserwowane w offsetowej analizie amplitud (zmiana amplitudy z offsetem) wywołane obecnością węglowodorów powodowane są anomalną wartością współczynnika Poissona w warstwie złożowej (obecność np. gazu istotnie zaniża wartość współczynnika Poissona). Dysponując zapisem offsetowym (tzw. składowymi) można z zapisu sejsmicznego pozyskać znacznie bogatszą informację niż tylko sam efekt anomalny widoczny na przekrojach sejsmicznych. Dodatkowymi atrybutami zapisu sejsmicznego korelowanymi z właściwościami warstwy złożowej a obliczanymi na podstawie zmienności amplitud z offsetem są impedancja fali P, impedancja fali S, wskaźnik fluid factor, parametry geomechaniczne λ⋅ρ, μ⋅ρ oraz współczynnik Poissona. W prezentowanym artykule autorzy przedstawiają wyniki pierwszej próby zastosowania szacowania parametrów geomechanicznych w aspekcie oceny właściwości złoża siarki. Do oceny tych parametrów niezbędne są informacje o parametrach petrofizycznych pozyskanych z badań geofizyki otworowej. W tym przypadku autorzy dysponowali danymi dotyczącymi porowatości, gęstości, zawartości siarki, oraz prędkości fali podłużnej P z dwóch otworów. Pomiar wartości prędkości fali poprzecznej S w warunkach produkcyjnych jest niezmiernie utrudniony i autorzy wykorzystali tu zależności opracowane na podstawie wcześniejszych badań opisanych w monografii autorstwa Jerzego Deca pt. Wysokorozdzielcze badania sejsmiczne w celu rozpoznania złoża siarki Osiek oraz określania zmian dynamicznych zachodzących w wyniku eksploatacji. Wieloletnie badania geofizyczne wskazują, że wraz ze spadkiem porowatości obserwuje się wzrost zawartości siarki. Jednocześnie w przypadku podwyższonych koncentracji siarki szkielet wapienny złoża jest bardziej sztywny, a złoże określane jest jako zbite. Dla takich warunków petrofizycznych złoże siarki wykazywać będzie wysokie wartości impedancji fali P i S, co skutkować będzie również wzrostem właściwości geomechanicznych λ⋅ρ i μ⋅ρ. Uzyskane wyniki zaprezentowane są na przykładzie profilu sejsmicznego wykonanego w kopalni siarki w Osieku. Profil ten przebiegał w linii otworów, w których określono podstawowe parametry złoża na podstawie geofizycznych badań otworowych.

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Authors and Affiliations

Jerzy Dec
Kamil Cichostępski
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Abstract

W ramach technologii fotowoltaicznych wyróżniamy obecnie trzy generacje. Pierwsza z nich to ogniwa z mono- i polikrystalicznego krzemu (c-Si), druga obejmuje ogniwa wykonane na bazie technologii cienkowarstwowej, zarówno z krzemu amorficznego (a-Si), jak i diseleneku indowo-miedziowo-galowego (CIGS), tellurku kadmu (CdTe) oraz arsenku galu (GaAs). Trzecia generacja to najnowsze technologie, takie jak: organiczne ogniwa słoneczne, ogniwa uczulane barwnikami czy ogniwa hybrydowe. Przyjmuje się, że średnia długość życia modułu fotowoltaicznego wynosi około 17 lat, co w połączeniu ze wzrastającym zainteresowaniem technologią fotowoltaiczną wiąże się ze zwiększona ilością odpadów, trafiających na składowiska. Oszacowano, że w 2026 roku liczba odpadowych modułów fotowoltaicznych osiągnie 5 500 000 ton. Będą to zarówno pozostałości po procesie produkcji, elementy uszkodzone podczas użytkowania oraz zużyte moduły fotowoltaiczne. Rozwój technologii fotowoltaicznych prowadzi również do doskonalenia istniejących i badań nad opracowaniem nowych metod recyklingu, dostosowanych do procesów produkcji modułów. W pracy zaprezentowano stan wiedzy na temat opracowanych technologii recyklingu modułów, wykonanych z krystalicznego krzemu oraz modułów cienkowarstwowych. Przedstawiono wyniki badań własnych nad procesem delaminacji modułów oraz roztwarzania elementów ogniw wykonanych w obu technologiach. W wyniku przeprowadzonych badań określono minimalną temperaturę, która powinna zostać zastosowana podczas dekompozycji materiału laminującego. U dowodniono, że folie wykonane przez różnych producentów ulegają procesom delaminacji w różnym stopniu, co może być spowodowane różnicami w stopniu usieciowana i stosunkowi polietylenu do polioctanu winylu. Przy wykorzystaniu metody trawienia sekwencyjnego podczas usuwania metalizacji można odzyskać nawet 1,6 kg srebra na 1 t połamanych mono- i polikrystalicznych ogniw krzemowych.
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Authors and Affiliations

Anna Kuczyńska-Łażewska
Ewa Klugmann-Radziemska
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Abstract

Obowiązująca dyrektywa IED, a co za tym idzie bardzo rygorystyczne wymagania względem rtęci (Hg) stawiane przez BAT/BREF, zmuszają polską energetykę do poszukiwania nowych wydajnych technologii oczyszczania spalin z gazowych jej form. Obecnie żadne z metod pierwotnych ani wtórych usuwania związków Hg w kraju nie jest w stanie sprostać tym restrykcjom. Wymagań tych nie spełniają nawet powszechnie stosowane metody z wykorzystaniem węgla aktywnego modyfikowanego bromem lub jodem czy też nowoczesne metody stosowane w innych krajach wykorzystujące moduły polimerowe. Związane jest to z dużym zanieczyszczeniem rtęcią paliw kopalnych stosowanych w krajowej energetyce. Dlatego też w ramach projektu pt. „Hybrydowe układy adsorpcyjne do redukcji emisji rtęci z zastosowaniem wysokoefektywnych komponentów polimerowych”, akronim HYBREM, podjęte zostały próby zbudowania innowacyjnej linii technologicznej łączącej kilka technik oczyszczania spalin ze szkodliwych związków rtęci. Do budowy instalacji pilotażowej wykorzystano technologie bazujące na modułach polimerowych oraz iniekcji różnych sorbentów stałych. Zaletą budowanej instalacji będzie jej mobilność, przez co może być testowana na różnych obiektach energetycznych. Otrzymane wyniki oczyszczania spalin przy użyciu zaprojektowanej instalacji pilotażowej pozwolą określić czy zbudowany prototyp jest efektywny w każdych warunkach dla polskich elektrowni opalanych węglem. Wiedza na ten temat pozwoli efektywnie rozwinąć technologie przemysłowe pod kątem oczyszczania spalin z rtęci spełniając jednocześnie wymagania stawiane przez konkluzje BAT/BREF.
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Authors and Affiliations

Magdalena Wdowin
Robert Żmuda
Wojciech Adamczyk
Łukasz Lelek
Sergiusz Mandrela
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Abstract

In order to assess the influence of hydrodynamic effects on the recovery of n-butanol by means of pervaporation, a commercial PERVAP 4060 membrane was investigated. Laboratory pervaporation experiments were carried out providing a comparison of the permeation fluxes and enrichment factors. While the enrichment factors achieved in both modules under the same process conditions were comparable, the permeation fluxes differed from each other. In order to explain the observed differences, hydrodynamic conditions in the membrane module were examined by means of CFD simulation performed with ANSYS Fluent 14.5 software. Two different modules having membrane diameters of 80 mm and 150 mm were analyzed. As a result, different velocity profiles were obtained, which served to estimate the mass transfer coefficients of butanol, ethanol and acetone.
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Authors and Affiliations

Joanna Marszałek
Michał Tylman
Paulina Rdzanek
Władysław Kamiński
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Abstract

MIMO technology has become very popular in a wireless communication system because of the many advantages of multiple antennas at the transmitting end and receiving end. The main advantages of MIMO systems are higher data rate and higher reliability without the need of extra power and bandwidth. The MIMO system provides higher data rate by using spatial multiplexing technique and higher reliability by using diversity technique. The MIMO systems have not only advantages, but also have disadvantages. The main disadvantage of MIMO system is that the multiple antennas required extra high cost RF modules. The extra RF modules increase the cost of wireless communication systems. In this research, the antenna selection techniques are proposed to minimize the cost of MIMO systems. Furthermore, this research also presents techniques for antenna selection to enhance the capacity of channel in MIMO systems.

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Authors and Affiliations

Dalveer Kaur
Neeraj Kumar
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Abstract

A cast iron is gradient material. This means that depending on the cooling rate it is possible, at the same chemical composition and the physicochemical state of molten metal, to obtain material with a different structure. The connection between the wall thickness of the casting and the speed of its cooling expresses the casting module. Along with the module escalation a cooling rate of the casting is reducing what can cause changes of the microstructure and the increased tendency to the crystallization of distorted graphite forms. Inspections of experimental castings from nodular cast iron with different modules were conducted to the graphite form.

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Authors and Affiliations

M. Hosadyna
St.M. Dobosz
J. Kusiński
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Abstract

Light-weight Self-Compacting Concrete (LWSCC) might be the answer to the increasing construction requirements of slenderer and more heavily reinforced structural elements. However there are limited studies to prove its ability in real construction projects. In conjunction with the traditional methods, artificial intelligent based modeling methods have been applied to simulate the non-linear and complex behavior of concrete in the recent years. Twenty one laboratory experimental investigations on the mechanical properties of LWSCC; published in recent 12 years have been analyzed in this study. The collected information is used to investigate the relationship between compressive strength, elasticity modulus and splitting tensile strength in LWSCC. Analytically proposed model in ANFIS is verified by multi factor linear regression analysis. Comparing the estimated results, ANFIS analysis gives more compatible results and is preferred to estimate the properties of LWSCC.

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Authors and Affiliations

B. Vakhshouri
S. Nejadi
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Abstract

The possibility of a normal distribution indicates that few particles are in the same phase during a breath and their reflections can be observed on the chest wall, then a few explosive waves with relatively large power occurr occasionally. Therefore, the one-cycle sine wave which is simulated as a single burst of the explosive effect phenomenon penetrates through the chest wall and was analysed to explore the reason of the crackle sounds. The results explain the differences between the definitions of crackle proposed by Sovijärvi et al. (2000a). The crackles in the lungs were synthesised by a computer simulation. When the coarse crackles occur, the results indicate that higher burst frequency carriers (greater than 100 Hz) directly penetrate the bandpass filter to simulate the chest wall. The simulated coarse crackle sounds were low pitched, with a high amplitude and long duration. The total duration was greater than 10 ms. However, for a lower frequency carrier (approximately 50 Hz), the fundamental frequency component was filtered out. Therefore, the second harmonic component of the lower frequency carrier, i.e., the fine crackle, penetrated the chest wall. Consequently, it is very possible that the normal lung sounds may contain many crackle-shaped waves with very small amplitudes because of the filtering effects of the chest wall, environment noises, electric devices, stethoscopes, and human ears, the small crackles disappear in the auscultations. In addition, our study pointed out that some unknown crackles of the very low frequency under the bandwidth of the human ears cannot penetrate the airways and be detected by medical doctors. Therefore, it might be necessary to focus advanced electronic instrumentation on them in order to analyse their possible characteristics for diagnosis and treatment of the respiration system.
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Authors and Affiliations

Bing-Yuh Lu
1 2
Meng-Lun Hsueh
3
Huey-Dong Wu
4

  1. Faculty of Automation, Guangdong University of Petrochemical Technology, No. 139, Sec. 2, Guando Road, Maoming City, Guangdong 525000, China
  2. Department of Electronic Engineering, Tungnan University, No. 152, Sec. 3., BeiShen Rd., ShenKeng Dist., New Taipei City 22202, Taiwan (R.O.C.)
  3. Department of Electronic Engineering, Hwa Hsia University of Technology, No. 111, Gongzhuan Rd., Zhonghe Dist., New Taipei City 235, Taiwan (R.O.C.)
  4. Section of Respiration Therapy, Department of Integrated Diagnostics and Therapeutics, National Taiwan University Hospital, No. 7, Zhongshan S. Rd., Zhongzheng Dist., Taipei City 100, Taiwan (R.O.C.)
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Abstract

Due to the multifold growth in demands of multimedia services and mobile data, the request for increased channel capacity in mobile and wireless communication has been quickly increasing. Developing a wireless system with more spectral efficiency under varying channel condition is a key challenge to provide more bit rates with limited spectrum. Multiple Input Multiple Output (MIMO) system with Orthogonal Frequency Division Multiplexing (OFDM) gives higher gain by using the direct and the reflected signals, thus facilitating the transmission at high data rate. An integration of Spatial Modulation (SM) with OFDM (SM OFDM) is a newly evolved transmission technique and has been suggested as a replacement for MIMO -OFDM transmission. In practical scenarios, channel estimation is significant for detecting transmitted data coherently. This paper proposes pilot based, Minimum Mean Square Error (MMSE) channel estimation for the SM OFDM communication system. We have focused on analyzing Symbol Error Rate (SER) and Mean Square error (MSE) under Rayleigh channel employing International Telecommunication Union (ITU) specified Vehicular model of Pilot based MMSE channel estimator using windowed Discrete Fourier Transform (DFT) and MMSE weighting function. Simulation output shows that proposed estimator’s SER performance lies close to that of the MMSE optimal estimator in minimizing aliasing error and suppressing channel noise by using frequency domain data windowing and time domain weighting function. Usage of the Hanning window eliminates error floor and has a compact side lobe level compared to Hamming window and Rectangular window. Hanning window has a larger MSE at low Signal to Noise Ratio (SNR) values and decreases with high SNR values. It is concluded that data windowing technique can minimize the side lobe level and accordingly minimize channel estimation error when interpolation is done. MMSE weighting suppresses channel noise and improves estimation performance. Since Inverse Discrete Fourier Transform (IDFT)/DFT transforms can be implemented with fast algorithms Inverse Fast Fourier Transform( IFFT)/Fast Fourier Transform (FFT) computational complexity can be remarkably reduced.
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Authors and Affiliations

Anetha Mary Soman
1
R. Nakkeeran
1
Mathew John Shinu
2

  1. Department of Electronics Engineering, School of Engineering and Technology, Pondicherry Central University, Pondicherry, India
  2. Department of Computer Science, St.ThomasCollege of Engineering & Technology, Kannur, Kerala, India
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Abstract

The performance of the multi-input multi-output (MIMO) systems can be improved by spatial modulation. By using spatial modulation, the transmitter can select the best transmit antenna based on the channel variations using channel state information (CSI). Also, the modulation helps the transmitter to select the best modulation level such that the system has the best performance in all situations. Hence, in this paper, two issues are considered including spatial modulation and information modulation selection. For the spatial modulation, an optimal solution for obtaining the probability of selecting antenna is calculated and then Huffman coding is used such that the transmitter can select the best transmit antenna to maximize the channel capacity. For the information modulation, a multi quadrature amplitude modulation (MQAM) strategy is used. In this modulation, the modulation size is changed based on the channel state variations; therefore, the best modu- lation index is used for transmitting data in all channel situations. In simulation results, the optimal method is compared with Huffman mapping. In addition, the effect of modulation on channel capacity and a bit error rate (BER) is shown.

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Authors and Affiliations

Bahar Ghaderi
Naser Parhizgar
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Abstract

In this paper we propose a new sliceable bandwidth variable transponder (SBVT) architecture with the separate analysis on the transmitter and receiver section. In transmission section we propose a distance module (DM) which is a programmable module. It divides a data stream/main stream (which employs a super-channel) into sub-stream and assigned modulation technique to each sub-stream based on their light path distance detailing the concept of sub-channel. In this paper, we have also proposed an algorithm for the distance module. Next we propose a modulation and transmission module (M&TM), where, planar light wave circuit (PLC) is used for enabling three modulation techniques (PM-16QAM, PM-QPSK and PM-BPSK). Finally, we propose the receiving section, which is designed to support three modulation techniques. It consists of two demodulator circuits, one for PM-16QAM/PM-QPSK and the other for PM-BPSK. In this proposed work, we focus on the multi-mode interference (MMI) devices (MMI coupler and MMI splitter) because of their photonic integration technology which is necessary for the implementation of SBVT. Lastly, we propose an elastic optical node architecture which removes the limitations of previously discussed node architecture for long distance communication.

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Authors and Affiliations

Ujjwal
T. Jaisingh
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Abstract

An alternative approach of the determining of conditions of safe stability loss of rectilinear motion of a wheeled vehicle model with controlled wheel module in the sense of N.N. Bautin is considered. The slipping forces are presented accurate within cubic expansion terms in the skid angles. Terms and conditions of safe stability loss depend on the ratio between the coefficients of resistance to the skid, the adhesion coefficients in the transverse direction of the axes and the parameter of torsional stiffness of the controlled wheel module. The presented approach to the analysis of real bifurcations related to the divergent loss of rectilinear motion mode stability has a clear geometric pattern: if in the vicinity of rectilinear motion at subcritical speed, there are additionally two unstable circular stationary states, then the stability limit is of dangerous nature in the sense of N.N. Bautin; if two circular stationary modes exist at supercritical speed, the limit of the stability loss in the parameter space of the longitudinal velocity is safe in the sense of N.N. Bautin. Analysis of the number of stationary modes in the vicinity of the critical velocity of rectilinear motion is performed for the obtained determining equation - cubic binomial.
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Authors and Affiliations

Alexandr Kravchenko
Vladimir Verbitskii
Valery Khrebet
Natalia Velmagina
Andrey Muranov
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Abstract

Perception takes into account the costs and benefits of possible interpretations of incoming sensory data. This should be especially pertinent for threat recognition, where minimising the costs associated with missing a real threat is of primary importance. We tested whether recognition of threats has special characteristics that adapt this process to the task it fulfils. Participants were presented with images of threats and visually matched neutral stimuli, distorted by varying levels of noise. We found threat superiority effect and liberal response bias. Moreover, increasing the level of noise degraded the recognition of the neutral images to higher extent than the threatening images. To summarise, recognising threats is special, in that it is more resistant to noise and decline in stimulus quality, suggesting that threat recognition is a fast ‘all or nothing’ process, in which threat presence is either confirmed or negated.

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Authors and Affiliations

Ewa Magdalena Król
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Abstract

The paper presents the results of research work on the development of a rapidprototyping test stand for testing: servo control algorithms, trajectory generation, algorithms for increasing overall quality of the feed-drive modules within two axis (X-Y) table of the milling machine. Open architecture interface of the prepared control system lets the potential user test functionality of integration of diagnostic tools within the motion controller - directly, without taking into account communication with top-level CNC system.

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Authors and Affiliations

Krzysztof Pietrusewicz
Michał Bonisławski
Rafał Pajdzik
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Abstract

We propose building a new PKC in a ring structure, the classification of rings being an open problem. The difficulty of the scheme is based on retrieving the eigenvalues of endomorphism on a finite type module over a non-commutative ring. It is resistant to a chosen cipher text attack. Working in the fraction ring of a non-commutative ring makes our scheme a zero-knowledge proof of knowledge, result indistinguishable, in the Naor-Yung model. Finally, a dramatic improvement in security is obtained through the drawing with uniform probability of the working ring at high frequency.
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Jean-François Geneste
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Abstract

In this study, the effect of electroless Pd-P plating on the bonding strength of the Bi-Te thermoelectric elements was investigated. The bonding strength was approximately doubled by electroless Pd-P plating. Brittle Sn-Te intermetallic compounds were formed on the bonding interface of the thermoelectric elements without electroless Pd-P plating, and the fracture of the bond originated from these intermetallic compounds. A Pd-Sn solder reaction layer with a thickness of approximately 20 µm was formed under the Pd-P plating layer in the case of the electroless Pd-P plating, and prevented the diffusion of Bi and Te. In addition, the fracture did not occur on the bonding interface but in the thermoelectric elements for the electroless Pd-P plating because the bonding strength of the Pd-Sn reaction layer was higher than the shear strength of the thermoelectric elements.

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Authors and Affiliations

Sung Hwa Bae
Se Hun Han
Injoon Son
Kyung Tae Kim
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Abstract

The research project “Railcab” designs a shuttle-based transportation system, which combines innovative mechatronic technologies with existing railway tracks. The traction and braking forces are generated by a linear electromagnetic drive while the tracking and guidance is performed using classical wheel/rail technology. By adopting different mechatronic modules, a modular structuring of the overall system, the driving safety, vehicle dynamics and the travelling comfort can be increased.

In the present paper, we concentrate on the development of the active tracking module which reduces the sensitivity of the system behaviour with respect to the friction in the wheel/rail contact. Basic ideas of the tracking module are self-optimizing active tracking, camber adjustment, and mechanical locking device. Based on a-priori identified risks, like e.g. strong cross-wind, frosted rails and crossing of switches, the safety concepts are described in detail together with the methodology that was used in the design process.

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Authors and Affiliations

Michael Walther
Thomas Muller
Jorg Wallaschek
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Abstract

This study focuses to develop a new hybrid Engineered Cementitious Composite (ECC) and assesses the performance of a new hybrid ECC based on the steel short random fiber reinforcement. This hybrid ECC aims to improve the tensile strength of cementitious material and enhance better flexural performance in an RC beam. In this study, four different mixes have been investigated. ECC with Poly Vinyl Alcohol (PVA) fiber and PolyPropylene (PP) fiber of 2.0% volume fraction are the two Mono fiber mixes; ECC mix with PVA fiber of 0.65% volume fraction hybridized with steel fiber of 1.35% volume fraction, PP fiber of 0.65% volume fraction hybridized with steel of 1.35% volume fraction are the two additional different hybrid mixes. The material properties of mono fiber ECC with 2.0 % of PVA is kept as the reference mix in this study. The hybridization with fibers has a notable achievement on the uniaxial tensile strength, compressive strength, Young’s modulus, and flexural behavior in ECC layered RC beams. From the results, it has been observed that the mix with PVA fiber of 0.65% volume fraction hybrid with steel fiber of 1.35% volume fraction exhibitimprovements in tensile strength, flexural strength, andenergy absorption. ThePP fiber of 0.65% volume fraction hybridized with steel of 1.35% volume fraction mix has reasonable flexural performance and notable achievement in displacement ductility overthe reference mix.

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Authors and Affiliations

A.R. Krishnaraja
Dr.S. Kandasamy
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Abstract

Amplitude modulation increases the annoyance caused by wind turbine noise. One gets the improved annoyance when a penalty is added to the measured or calculated time-average sound level. The amplitude modulated wind turbine noise consists of pulses. Each of them could be characterized by the short timeaverage sound level and the modulation depth. The latter determines the pulse penalty. This paper shows how to calculate the improved annoyance of amplitude modulated wind turbine noise, when the short time-average sound level and the penalty for each pulse are known. A special case of identical pulses is discussed. The proposed methodology needs to be tested by research.
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Authors and Affiliations

Rufin Makarewicz
1

  1. Chair of Acoustics, Faculty of Physics, Adam Mickiewicz University, Poznan, Poland
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Abstract

Amplitude modulated noise from a single wind turbine is considered. The time-varying modulation depth D_m and the short time-average sound level L_Aeq,τ (with τ = 20 s) are measured at the reference distance d_*. Due to amplitude modulation, a penalty has to be added to L_Aeq,τ. The paper shows how to calculate the corrected long-term time-average sound level L ̂_AeqT (with T >> 20 s), which accounts for amplitude modulation, at any distance d ≠ d_* from the wind turbine. The proposed methodology needs to be tested by research
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Authors and Affiliations

Rufin Makarewicz
1
Maciej Buszkiewicz
1

  1. Faculty of Physics, Adam Mickiewicz University, Poznan, Poland
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Abstract

The main focus of the article is an advanced actuator, designed and optimized for small dynamic legged robots. The presented actuator prototype is unique, as the market lacks similar solutions when dimensions and weight of the module are considered. The actuator has a modular structure, which makes it easy to replace in case of malfunction and simplifies the overall structure of the robot. High torque bandwidth, achieved by the module, is crucial to agile locomotion, obstacle avoidance and push recovery of the quadrupedal robot. The Authors have conducted a solution review aimed at similar small-size modules. It was found that there are no advanced actuators suitable for sub 5 kg quadruped robots. The unique design presented in this paper is described in all three aspects: mechanical, electrical and software. The mechanical section depicts the solutions implemented in the module, especially the low gear ratio gearbox. The custom brushless motor driver is presented in the electrical section, together with detailed diagrams and hardware descriptions. The last section depicts solutions implemented in the software, the main motor control algorithm and auxiliary modules such as automatic motor parameter identification and encoder misalignment correction. Tests performed in the last part of this paper validated the design goals established for the actuator. The results confirmed the high torque capability and exhibited the motor saturation region. Continuous and peak torque were measured based on the thermal characteristics of the module. Moreover, the automatic motor parameter identification process carried out by the controller itself was validated by manual measurements.
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Authors and Affiliations

Piotr Wasilewski
1
Rafał Gradzki
2
ORCID: ORCID

  1. Bialystok University of Technology, Faculty of Electrical Engineering, Wiejska 45D, 15-351 Bialystok, Poland
  2. Bialystok University of Technology, Faculty of Mechanical Engineering, Department of Robotics and Mechatronics, Wiejska 45C, 15-351, Bialystok, Poland

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