2018 - Repozytorium publikacji - Politechnika Gdańska

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Analysis of IMS/NGN Call Processing Performance Using Phase-Type Distributions Based on Experimental Histograms
- Sylwester Kaczmarek
- Maciej Sac
2018 Advances in Intelligent Systems and Computing
The paper describes our further research done with the proposed analytical and simulation traffic models of the Next Generation Network (NGN), which is standardized for delivering multimedia services with strict quality and includes elements of the IP Multimedia Subsystem (IMS). The aim of our models of a single IMS/NGN domain is to evaluate two standardized call processing performance parameters, which appropriate values are very important for satisfaction of users and overall success of the IMS/NGN concept. These parameters are mean Call Set-up Delay E(CSD) and mean Call Disengagement Delay E(CDD). Our latest investigations concern improving the conformity of the analytical results and experimental results obtained using the simulation model, which implements the operation of real network elements according to current standards and research. In this paper the results of calculations using PH/PH/1 queuing systems are presented, in which arrival and service distributions are phase-type distributions computed using maximum likelihood and distance minimization fitting algorithms based on experimental histograms. Presented latest results are compared to these obtained using other, previously investigated queuing systems. Additionally, computational complexity of all examined queuing systems is analyzed. As a result, some general remarks concerning all tested queuing systems and their applicability to NGN are provided.
Analysis of load carrying capacity and destruction mechanism of an intermediate anchorage steel plate for pillar jib crane
- Małgorzata Gordziej-Zagórowska
- Wojciech Migda
2018 Pełny tekst MATEC Web of Conferences
Pillar jib cranes are often mounted to existing floors with the use of an intermediate anchorage steel plate instead of using independent foundations, what is shown in the figure. Standards for steel design provide only basic rules for the design of such an intermediate plate. This study presents a simple design approach by using a numerical model in order to analyze different parameters that have significant influence in the anchorage of a interme-diate steel plate to a concrete floor. The goal was to show how to safely design a intermedi-ate plate but also to highlight important design parameters and also to present possible failure mechanisms in reference to the main design parameters.
Analysis of Lombard speech using parameterization and the objective quality indicators in noise conditions
- Krzysztof Kąkol
- Grazina Korvel
- Bożena Kostek
2018
The aim of the work is to analyze Lombard speech effect in recordings and then modify the speech signal in order to obtain an increase in the improvement of objective speech quality indicators after mixing the useful signal with noise or with an interfering signal. The modifications made to the signal are based on the characteristics of the Lombard speech, and in particular on the effect of increasing the fundamental frequency F0. The recording session includes sets of words and sentences in Polish, recorded in silence, as well as in the presence of interfering signals, i.e. pink noise and so-called bustle (called babble speech), also referred to as the “cocktail-party” effect. Research on the Lombard speech often focuses on subjective studies of speech intelligibility. There are, however, objective indicators such as PESQ (Perceptual Evaluation of Speech Quality) and P.563, which are used in studies of quality of telecommunication channels. The study shows that increasing the fundamental frequency results in increased values of the speech quality index, measured using the PESQ (Perceptual Evaluation of Speech Quality) standard. The research carried out consists of several stages: (1) recording speech samples (words and sentences) without and in the presence of pink noise and babble speech (the so-called cocktail party effect), i.e. the reference signal (“clean” speech), and then recording the same words/sentences in the presence of additional disturbances forcing the Lombard effect in speech recordings to occur; (2) analyzing differences between “clean” speech and the Lombard speech based on objective audio parameters; (3) mixing speech recordings with pink noise with a different signal to 36 10th International Workshop on noise ratio (SNR) in order to measure PESQ MOS coefficients; (4) measuring the PESQ coefficients of the reference files (“clean speech”) that are processed by increasing the F0 value and sound intensity level, and then the same files mixed with pink noise and babble speech interfering signals; (5) repeating step (2), i.e. analyzing the difference in objective parameters and indicating whether these differences are statistically significant.
Analysis of luminance distribution uniformity in CAVE-type virtual reality systems
- Adam Mazikowski
2018 Pełny tekst OPTO-ELECTRONICS REVIEW
In recent years, many scientific and industrial centers in the world developed a virtual reality systems or laboratories. The effect of user “immersion” into virtual reality in such systems is largely dependent of optical properties of the system. In this paper, problems of luminance distribution uniformity in CAVE-type virtual reality systems are analyzed. For better characterization of CAVE luminance nonuniformity corner and edge CAVE nonuniformity were introduced. Based on described CAVE-type virtual reality laboratory, named Immersive 3D Visualization Lab (I3DVL) just opened at the Gdansk University of Technology luminance nonuniformity of the system is evaluated and discussed. Data collection of luminance distribution allows for software compensation of intensity distribution of individual images projected onto the screen (luminance non-uniformity minimization) in the further research.
Analysis of odour interactions in model gas mixtures using electronic nose and fuzzy logic
- Bartosz Szulczyński
- Jacek Namieśnik
- Jacek Gębicki
2018 Pełny tekst CHEMICAL ENGINEERING TRANSACTIONS
Measurement and monitoring of air quality in terms of odour nuisance is an important problem. Although the source of these nuisances is different (e.g. wastewater treatment plants, municipal landfills), their common feature is that they are a complex mixture of odorants with different odour thresholds. An additional problem is occurrence of the odour interactions between mixture components. From a practical point of view, it would be most valuable to directly link the odour intensity with the results of analytical air monitoring. This would allow the on-line odour monitoring using electronic noses, which perform a holistic analysis of the gas mixtures composition (like olfactometric methods). The paper presents the possibility of application of fuzzy logic to determine the odour intensity and indicate odour interactions in model, five-component gas mixtures (acetone, α-pinene, formaldehyde, toluene and triethylamine) using electronic nose prototype. As the results of the studies, it was found the electronic nose prototype along with the fuzzy logic pattern recognition system can be successfully used for this application. The results obtained using fuzzy logic are consistent with sensory analysis results in 80%.
Analysis of pavement structure sensitivity to passage of oversized heavy duty vehicle in terms of bearing capacity
- Dawid Ryś
- Piotr Jaskuła
2018 Pełny tekst IOP Conference Series: Materials Science and Engineering
Oversized heavy duty vehicles occur in traffic very rarely but they reach extremely high weights, even up to 800 tonne. The detrimental impact of these vehicles on pavement structure is much higher than in case of commercial vehicles that comprise typical traffic, thus it is necessary to assess the sensitivity of pavement structure to passage of oversized vehicles. The paper presents results of sample calculations of load equivalency factor of a heavy duty oversized vehicle with usage of mechanistic-empirical approach. The effects of pavement thickness, type of distress (cracking or rutting) and pavement condition (new or old with structural damage) were considered in the paper. Analysis revealed that a single pass of an 800 tonne oversized vehicle is equivalent to pass of up to 377 standard 100 kN axles. Load equivalency factor calculated for thin structures is almost 3 times lower than for thick structures, however, the damage effect caused by one pass of an oversized vehicle is higher in the case of thin structure. Bearing capacity of a pavement structure may be qualified as sufficient for passage of an oversized heavy duty vehicle when the measured deflection, for example in an FWD test, does not exceed the maximum deflections derived from mechanistic-empirical analysis. The paper presents sample calculation of maximum deflections which allow to consider passage of an oversized vehicle as safe over different pavement structures. The paper provides road administration with a practical tool which helps to decide whether to issue a permit of passage for a given oversized vehicle.
Analysis of Reasons of Accidents Between Cyclists and Public Transport Vehicles in Cities
- Marek Bauer
- Wiesław Dźwigoń
- Romanika Okraszewska
2018
In European cities, a bicycle is now or is systematically becoming an equal means of transport. Unfortunately, the growth of bicycle traffic is associated with an increase in the number of accidents involving cyclists. Some of these accidents, are events with cyclists and public transport vehicles - and therefore means of transport, which together are to constitute a serious alternative to a car. Although the share of these kind of accidents is relatively small - each such event has a very negative impact on the perception of ecological forms of transport. The paper discusses types of events between cyclists and public transport vehicles, with the identification of dangerous behaviours of cyclists and drivers. The most frequent reasons of these events are discussed, taking into account the places of occurrence of accidents, type and condition of bicycle and public transport infrastructure and types of behaviours of traffic participants. The research part of the paper presents statistical analyses of the number of accidents between cyclists and public transport vehicles, as well as statistics describing the number of victims in accidents in the six largest Polish cities. Based on detailed descriptions of events - using statistical tools - accidents were analysed in terms of identifying the most important reasons of their occurrence and circumstances conducive to the occurrence of accidents. The article was crowned with the recommendations for the application of solutions reducing the risk of accidents.
Analysis of results of large-scale multimodal biometric identity verification experiment
- Piotr Hoffmann
- Andrzej Czyżewski
- Piotr Szczuko
- Adam Kurowski
- Michał Lech
- Maciej Szczodrak
2018 Pełny tekst IET Biometrics
An analysis of a large set of biometric data obtained during the enrolment and the verification phase in an experimental biometric system installed in bank branches is presented. Subjective opinions of bank clients and of bank tellers were also surveyed concerning the studied biometric methods in order to discover and to explore relations emerging from the obtained multimodal dataset. First, data acquisition and identity verification methods are described in the paper. Then, relationships between ratios of successful and failed verifications between pairs, triplets, and quartets of biometric modalities are studied. An analysis of the sentiment of clients and of banking tellers related to each identity verification attempt was performed based on linguistic methods. The data mining process is described, based on the rough sets methodology, aimed at deriving rules pertaining to consecutive identity verification attempts.
Analysis of temporary steel grandstand with different bracing systems exposed to crowd load
- Natalia Lasowicz
- Tomasz Falborski
- Robert Jankowski
2018 Pełny tekst Journal of Measurements in Engineering
Grandstands are structures which are regularly subjected to dynamic loads generated by crowd motions. It is a dangerous situation when spectators induce rhythmic jumping, dancing, stamping, etc. If the synchronized movement of spectators excites a natural frequency of the structure, resonant response might occur. To avoid such situations, temporary steel grandstands are commonly strengthened using additional elements that create bracing system which is selected depending on the size of the structure, type of the event, acting load, etc. It was proved that not only the use but also the arrangement of such structural members is crucial for the dynamic structural resistance. The aim of the present study is to determine the most effective arrangement of bracing system for a typical example of the temporary steel grandstand which is exposed to dynamic load induced by spectators. Three different arrangements of bracing systems have been analysed using five criteria recommended in the literature. The results of the study clearly show that the dynamic parameters of the grandstand are substantially different for various types of bracing systems. The largest improvement in the structural behaviour has been obtained for the grandstand equipped with the bracing system satisfying all proposed criteria. The peak accelerations for this case have been found to be nearly twice as low as for structures with other bracing arrangements. The application of such a system for the grandstand which is exposed to human-induced vibrations allows for safe use of the structure as well as improves comfort of spectators.
Analysis of the Accuracy of Pulse Estimation Using Smart Watches
- Kamila Wasilewska
- Jacek Rumiński
2018
The purpose of this paper is to perform an analysis of the accuracy of the pulse estimation by comparing readings from a smartwatch with readings from medical devices. The study required writing applications that allow continuous pulse measurement. As a result, two applications were created for the smartwatch. The first one is dedicated to Android Wear devices, while the other one is compatible with Tizen watches. The next step was to create another application using a phone with a camera and a flashlight. The current heart rate value could be obtained by putting a finger to the lens of the camera and its flashlight, followed by a suitable pulse calculation algorithm. At the end of the experiment, a short and non-obligatory form for the gender, age and cardiovascular diseases of the person could be filled and the results are recorded in the database in a way that they could be compared with the measurements from watches. After collecting the intended amount of measurements, it was necessary to send a measurement file to a computer that could calculate the heart rate estimations. Obtaining these values has allowed to draw conclusions about the accuracy and reliability of pulse measurement using a mobile devices.
Analysis of the cyclic load-unload-reload tests of VALMEX aged fabric
- Krzysztof Żerdzicki
- Paweł Kłosowski
- Krzysztof Woźnica
2018 Pełny tekst
The paper presents mechanical response of the VALMEX fabric during the cyclic loading-unloading and re-loading experiments. Two types of the aged material used for nearly 20 years as the roofing of the Forest Opera in Sopot (Poland) have been tested. The results have been separately obtained for the warp and fill di-rections. The comparative analysis has revealed that the material aged in service is more durable in the fill di-rection, but less durable in the warp direction. It has been also shown, that the material aged in service has kept its high strength properties and could be longer used in the real structure
Analysis of the impact of socio-economic development on road safety based on the example of Baltic Sea Region countries
- Kazimierz Jamroz
- Aleksandra Romanowska
- Marcin Budzyński
2018 Pełny tekst
Baltic Sea Region (BSR) is a specific region of Europe, bringing together countries with different levels of socio-economic development. The main common point is territorial access to the Baltic Sea and the importance of maritime transport in the transportation of goods. The region consists of 9 countries, including Germany, Poland, Lithuania, Latvia, Estonia, Finland, Sweden, Denmark and Russia (more specifically, Kaliningrad and Leningrad Oblast), of which all, except Russia, are members of the European Union. BSR is an extremely important European region. With the most competitive economies of the world (Scandinavian countries, Germany, Finland), the region (excluding Russia) generates 30% of European GDP. The specificity of BSR is, however, very diverse. The countries differ in almost every way, economic, political, social or cultural. For many years Eastern Europe countries (EEC) versus Western Europe and Scandinavian countries (WEC) have been shared by a large economic and social distance. These differences, although diminishing in result of political transformations, are not without impact on other areas of life. Although Europe is the continent with the lowest level of danger regarding fatal road crashes, when analysing road safety data of the BSR countries we can observe the impact that the socio-economic situation has on road safety. Against the backdrop of other countries, highly developed WEC countries can be clearly distinguished having the lowest road fatality rates. Sweden, in result of implementing Vision Zero, achieved one of the world lowest road fatality rates. On the other hand, Russia can be distinguished with more than twice higher road fatality rate than in other EEC and with the same indicator 5-8 times higher than in WEC countries. Base on the data collected for BSR countries, attempts were made to analyze and assess the impact of the level of socio-economic development on road safety in the road network of analyzed countries. The results are discussed in the paper.
ANALYSIS OF THE LOAD-CARRYING CAPACITY OF A HYDRODYNAMIC WATER-LUBRICATED BEARING IN A HYDROELECTRIC POwER PLANT
- Artur Olszewski
- Tomasz Żochowski
- Grzegorz Gołębiewski
2018 Pełny tekst TRIBOLOGIA
The paper presents an analysis of the load-carrying capacity of a historic hydrodynamic water-lubricated radial bearing of an unconventional segment design installed in the Braniewo Hydroelectric Power Plant. The aim of the calculations was to determine whether the bearing operates in the conditions of hydrodynamic or mixed lubrication, as well as to establish the optimal geometry of the axial grooves allowing for the highest load-carrying capacity. Computer simulations were performed using proprietary ARTbear software developed at Machine Design and Vehicles Department of Gdańsk University of Technology. The calculation results led to the creation of the technical documentation of the bearing’s modernization serving to increase its lifespan and reliability.
Analysis of the relationship between the length of eye fixation and the parameters of advertisements visible from the road
- Tomasz Mackun
- Joanna Żukowska
2018 Pełny tekst MATEC Web of Conferences
In Poland, many advertising signs addressed to motorists are located along the roadside. Advertisements do not serve any traffic related purpose and can distract drivers making them less reliable and as a consequence, reduce road safety. The existing regulations only apply to the carriageway. The research is conducted as part of the RID project. The objective of the RID project is to create a "Manual for positioning roadside advertising signs". The research aims to establish whether drivers look at roadside advertising and for how long. An additional goal is to investigate the correlation between the number and duration of the driver's eye fixation and the parameters of advertising media. In their work the authors use a mobile eye tracker. The study included a group of 60 drivers who drove on a section of about 110 km which included roads of various technical classes, different cross-sections and featured a varied roadside development pattern. 2,900 advertising carriers were inventoried on the route. Almost 30% of all advertising media drew the gaze. The billboards on which fixations were registered in the studied group were inventoried in detail for their geometrical, location or content parameters. The authors of the article present the relations between the parameters and their ability to attract the attention of drivers depending on the number of fixations and their duration.
Analysis of turnouts with non-linear curvature of diverging track for different train running speeds
- Władysław Koc
2018 Pełny tekst Problemy Kolejnictwa
The paper deals with the issue of shaping a variable curvature in the diverging track of the railway turnout. Solution without a circular arc in the central zone, comprising two zones of non-linear curvature, of the same length, having zero curvature values at the end points, was adopted as a model, on the basis of the previously conducted dynamic tests. Optimum type of curvature was selected from the point of view of the kinematic conditions. An analytical record of the curvature and of the tangent inclination angle along the diverging track and of the Cartesian coordinates of the diverging track are presented. Obtained theoretical correlations were verified by computing. Verified correlations were used to determine geometrical parameters of some turnouts with non-linear curvature of the diverging track for different assumed train running speeds on the diverging track. The criterion was to minimize the length of the entire turnout having predefined ordinate of the end of its diverging track.
Analysis of volatile fraction of sweetie (Citrus maxima × Citrus paradisi) and its parent fruit using proton transfer reaction mass spectrometry
- Anna Różańska
- Dorota Sieńska
- Tomasz Dymerski
- Jacek Namieśnik
2018 Pełny tekst MONATSHEFTE FUR CHEMIE
The quality of the fruit is affected by several main ingredients and the aroma plays a fundamental role during the selection of fruit by consumers. In the case where several fruit have similar aromas and only one of them has specific health properties, it is very important to find the differences in the volatile organic compounds (VOCs) composition to distinguish these samples. Such situations are often found for hybrid fruit. Sweetie is a hybrid of grapefruit and pummelo. Sweetie fruit is characterized by high antioxidant potential and a positive effect on human health. The aim of this study was to verify the unique volatile compositional traits of three species of citrus fruit. Proton transfer reaction Time-of-Flight mass spectrometry (PTR-TOF-MS) was utilized to obtain the mass-resolved fingerprints of VOCs. The chemical formula of these VOC masses was tentatively identified. Principal component analysis was performed to evaluate the differences between the groups.
Analytical and legislative challenges of sewage sludge processing and management
- Bartłomiej Cieślik
- Lesław Świerczek
- Piotr Konieczka
2018 Pełny tekst MONATSHEFTE FUR CHEMIE
This article presents the most popular methods of sewage sludge management and analytical techniques which could be a powerful tool in designing new sewage sludge management methods. Chemical analysis is also described as a vital point at the subsequent stages of technological processes control and sewage sludge quality assessment. It is also an instrument essential to maintaining control of processed sewage sludge introduced to the environment as ready-to-use materials. The sludge management method is conditioned by the compliance with legal acts concerning sludge management. The most important of these contain information regarding allowable concentrations of pollutants which can be released into the environment, and the most important declarations concerning sewage sludge management. Various analytical techniques and preparation methods that can be used during the monitoring of the managed and processed sewage sludge are described. The most important are chromatographic techniques, methods based on inductively coupled plasma, and mass spectrometry based methods.
Analytical Steady-State Model of the Pipeline Flow Process
- Zdzisław Kowalczuk
- Marek Sylwester Tatara
2018 Pełny tekst
The paper addresses the issue of modeling the flow process in transmission pipelines. A base model used for numerical simulation is introduced. Under certain assumptions concerning steady state analysis, the differential equations describing the process are solved analytically for two cases: zero and nonzero inclination angle α. These equations describe a constant flow rate and a corresponding distribution of the pressure along the considered pipeline for both cases. The pipe length at which the pipeline is choking (the mass flow is equal zero) for given boundary pressures and inclination angle, is also derived. Convergence of the proposed solution for inclination angle α → 0 to the zero tilt solution, is proved. An exemplary practical relationship based on obtained equations is provided as a 3D chart. A test pipeline with adjustable inclination angles of its selected parts is considered. The analytic solution for the effective angle is compared with numerical solutions, which show relevant discrepancies between the results obtained for nonzero angles. Clearly, the numerical solution for a straight pipeline (with the increasing number of segments) is convergent to the analytic solution. Moreover, up to 16◦, the analytic approximation (using an effective inclination angle) is sufficient, and produces similar results as the numerical simulation.
Analyzing energy/performance trade-offs with power capping for parallel applications on modern multi and many core processors
- Adam Krzywaniak
- Jerzy Proficz
- Paweł Czarnul
2018 Pełny tekst Annals of Computer Science and Information Systems
In the paper we present extensive results from analyzing energy/performance trade-offs with power capping observed on four different modern CPUs, for three different parallel applications such as 2D heat distribution, numerical integration and Fast Fourier Transform. The CPU tested represent both multi-core type CPUs such as Intel⃝R Xeon⃝R E5, desktop and mobile i7 as well as many-core Intel⃝R Xeon PhiTM x200 but also server, desktop and mobile solutions used widely nowadays. We show that using enforced power caps we can find points of lower than default energy consumption but mostly for desktop and mobile solutions at the cost of increased execution time. We show with particular numbers how energy consumed, power consumption and execution time change for the point of minimum energy used versus the default configuration with no power limit, for each application and each tested CPU.
Annual variability of heavy metal content in Svalbard reindeer faeces as a result of dietary preferences
- Michał Węgrzyn
- Paulina Wietrzyk
- Sara Lehmann-Konera
- Stanisław Chmiel
- Żaneta Polkowska
2018 Pełny tekst ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
During both winter and summer, Svalbard reindeer selectively feed on different types of vegetation that are not only a source of nutritional value, but also a place of heavy metal accumulation. In the present study, the content of cadmium, chromium, copper, iron, lead, nickel, manganese, and zinc in reindeer excrement was measured. The main aims were to determine the seasonal content of several heavy metals in Svalbard reindeer faeces, and to compare their values in terms of dietary preferences during the year. Summer and winter reindeer excrement was gathered along a designated linear transect running through Bolterdalen and the vegetation described on 1 m2 plots. All of the analysed heavy metals were detected in the reindeer faeces and this fact seems to be connected with the incomplete content of these elements in an animal’s tissue after forage digestion. Analysis showed differences between summer and winter excrement in terms of concentrations of cadmium, chromium, iron, and nickel, but no differences were found for the other four elements analysed (manganese, lead, zinc, and copper). However, concentrations of heavy metals in faeces are rather low in comparison with both the levels in the vegetation that may be grazed by reindeer and in reindeer tissue.