Filters
total: 10359
filtered: 8011
-
Catalog
Chosen catalog filters
displaying 1000 best results Help
Search results for: ENERGY FIELD INTENSITY FATIGUE LIFE PREDICTION CRACK INITIATION SITES CRACK GROWTH DIRECTION BENDING-TORSION LOADING
-
Cogenerative micro power plants - a new direction for development of power engineering?
PublicationW pracy przedstawiono rozważania dotyczące perspektywy mikrosiłowni domowych w gospodarce rozproszonej. Przedstawiono oryginalne kryterium doboru czynnika roboczego w mikrosiłowni oraz przedstawiono sprawności cieplne i egzergetyczne obiegów Clausiusa-Rankina realizujących pracę mikrosiłowni.
-
New direction of education on mechanical engineering faculty in gdansk university of technology
PublicationW artykule opisano szczegółowo kierunki kształcenia wprowadzone w ostatnich latach na Wydziale Mechanicznym Pol. Gd. Przedstawiono ofertę kształcenia na nowych kierunkach takich jak Mechatronika, Inżynieria Mechaniczno-Medyczna oraz Zarządzanie i Inżynieria Produkcji dla studiów stacjonarnych pierwszego stopnia. Opisano również własne doświadczenia w implementacji procesu Bolońskiego trójstopniowego kształcenia w systemie European...
-
Fertility rebound and economic growth. New evidence for 18 countries over the period 1970-2011.
PublicationLong-run impact of economic growth on fertility trends is ambiguous and sensitive for in-time variations. Noticeably, over last decades, economic growth has led in many countries to significant falls in total fertility rates. However, recently, in high-income economies a kind of ‘fertility rebound’ emerged (Goldstein, 2009; Luci and Thevenon, 2011; Day, 2012), which supports the hypothesis that reversal trends in total fertility...
-
Optimisation and field assessment of poroelastic wearing course bond quality
PublicationCompared to typical asphalt mixtures, poroelastic mixtures are characterised by high porosity and high flexibility, which are desirable for traffic noise reduction. However, the same properties increase the risk of debonding from the lower layer, which is a significant source of premature damage. The study investigates which of the factors – tack coat agent, type and texture of the lower layer – have the greatest impact on interlayer...
-
Deformation Analysis of a Composite Bridge during Proof Loading Using Point Cloud Processing
PublicationRemote sensing in structural diagnostics has recently been gaining attention. These techniques allow the creation of three-dimensional projections of the measured objects, and are relatively easy to use. One of the most popular branches of remote sensing is terrestrial laser scanning. Laser scanners are fast and efficient, gathering up to one million points per second. However, the weakness of terrestrial laser scanning is the...
-
The Influence of Antitumor Unsymmetrical Bisacridines on 3D Cancer Spheroids Growth and Viability
PublicationThe culture of 3D spheroids is a promising tool in drug development and testing. Recently, we synthesized a new group of compounds, unsymmetrical bisacridines (UAs), which exhibit high cytotoxicity against various human cell lines and antitumor potency against several xenografts. Here, we describe the ability of four UAs—C-2028, C-2041, C-2045, and C-2053—to influence the growth of HCT116 and H460 spheres and the viability of HCT116...
-
The influence of moderate pressure and subzero temperature on the shelf life of minced cod, salmon, pork and beef meat
PublicationThe effect of moderate pressure at subzero temperature on natural microflora of minced cod, salmony, pork and beef meat was studied. Pressure of 193 MPa at –20 °C caused reduction of total bacterial count in pork and beef meat by 1.1 and 0.6 log cycles, respectively, and by about 1.5 log cycles in fish meat. Under these conditions the psychrophilic and psychrotophic bacteria were below the detection limit (<10CFU/g of sample) in...
-
Where/when/how did life begin? A philosophical key for systematizing theories on the origin of life
Publication -
Strength analysis of container ship subjected to torsional loading
PublicationThe objective of this work is to investigate the torsional response of a container ship, with particular consideration of the warping effect. Two different models are investigated. In the first case, the full length model of a ship is analyzed and a distributed load is applied with the use of a novel approach. The model is supported in the torsional centre of the cross-section, which is derived analytically. In the second case,...
-
Progress in the post weld residual stress evaluation using Barkhausen effect meter with a novel rotating magnetic field probe
PublicationWe report the progress in post weld residual stress evaluation using Barkhausen effect (BE) meter with rotating magnetic field probe. The novel probe of the BE meter contains two C-core electromagnets and searching coil with ferrite antenna. This meter allows automatic measurements of BE intensity envelopes at different angles of magnetizing field. The full process of measurement at given position of the probe takes about only...
-
Robust Parameter Estimation and Output Prediction for Reactive Carrier-Load Nonlinear Dynamic Networks
PublicationIn this paper an extension of on-line model simplification technique for a class of networked systems, namely reactive carrier-load nonlinear dynamic networked system (RCLNDNS), kept within point-parametric model (PPM) framework is addressed. The PPM is utilised to acquire a piece wise constant time-varying parameter linear structure for the RCLNDNS suitable for the on-line one step ahead prediction that may be applied to monitoring...
-
Disturbances of Earth magnetic field caused by eddy currents of airplane
PublicationThe uniform magnetic field of the Earth in the surrounding of a mobile, metallic object undergoes deformation by eddy currents. The influence of the moving, conducting object on the Earth's total magnetic field depends on the object's shape, position and speed of the changes relative to the magnetic field vector of the Earth, as well as the electric conductivity and the relative magnetic permeability of the material. Disturbances...
-
Experimental investigation and process parameter optimization of sheet metal bending by line heating method
PublicationThe present study is concerned with the experimental investigation of sheet metal deforming by line heating method that incorporates the combined effect of traverse speed of the torch, thickness of the sheet metal, and the number of passes of the torch. For the numerical analysis of metal bending by line heating, the
-
RECSYS CHALLENGE 2015: a BUY EVENT PREDICTION IN THE E-COMMERCE DOMAIN
PublicationIn this paper we present our approach to RecSys Challenge 2015. Given a set of e-commerce events, the task is to predict whether a user will buy something in the current session and, if yes, which of the item will be bought. We show that the data preparation and enrichment are very important in finding the solution for the challenge and that simple ideas and intuitions could lead to satisfactory results. We also show that simple...
-
Energy Yield Generated by a Small Building Integrated Photovoltaic Installation
PublicationIn the recent years photovoltaic (PV) industry has experienced a major growth, caused by the ever present annual decrease in module production prices and the expanding awareness of the general public in terms of renewable energy. There are numerous ways to implement PV modules as an additional energy source for a building, be it mounted on the rooftop, or building integrated (BIPV). An analysis of BIPV consisting of 8 modules with...
-
Intentional model of SMES growth
PublicationRozdział opisuje rolę intencji w funkcjonowaniu firmy. Autorzy opracowali intencyjny model wzrostu, który został opisany w oparciu o przeprowadzone badania w ramach Pomorskiego Obserwatorium Gospodarczego.
-
The role of trade in intra industry productivity growth - the case of old and new European Union countries.
PublicationThe purpose of this paper is to evaluate the role of trade in productivity growth in a sample of 30 sectors in 25 EU countries in the period of rapid East–West integration (1995–2007). Shift-share analysis is used to show that changes in value added per hour worked in these countries appear to be mainly due to positive developments (rising productivity) within single industries and only to a lower extent result from a shift towards...
-
Growth and Isolation of Large Area Boron‐Doped Nanocrystalline Diamond Sheets: A Route toward Diamond‐on‐Graphene Heterojunction
PublicationMany material device applications would benefit from thin diamond coatings, but current growth techniques, such as chemical vapor deposition (CVD) or atomic layer deposition require high substrate and gas‐phase temperatures that would destroy the device being coated. The development of freestanding, thin boron‐doped diamond nanosheets grown on tantalum foil substrates via microwave plasma‐assisted CVD is reported. These diamond...
-
Energy roadmaps for the city of Gdańsk
PublicationThe paper presents energy roadmaps for Gdansk in three time perspectives: short-term (the year 2012), medium-term (2020) and long-term (2050). The paper is a result of the research carried out under the PATH-TO-RES project, supported by European Commission programme SAVE Altener Intelligent Energy Europe.
-
Coastal Cliffs Monitoring and Prediction of Displacements Using Terrestial Laser Scanning
PublicationCoastal cliffs are very sensitive to degradation caused by erosion and abrasion. Thus, it is very important to monitor susceptibility of the cliffs in terms of slope angles and ground fall resulting from vertical morphology of the cliffs. The results could be used for example to establish the boundaries of the safe investments zone or retreat infrastructure buildings in case of real threat such as degradation of the objects of...
-
Electromagnetic interference frequencies prediction model of flyback converter for snubber design
PublicationSnubber design for flyback converters usually requires experimental prototype measurements or simulation based on accurate and complex models. In this study simplified circuit modelling of a flyback converter has been described to dimension snubbers in early stage of design process. Simulation based prediction of the transistor and diode ringing frequencies has been validated by measurements in a prototype setup. In that way obtained...
-
Integrated plant-wide modelling for evaluation of the energy balance and greenhouse gas footprint in large wastewater treatment plants
PublicationModern wastewater treatment plants (WWTPs) should maintain a balance between three combined sustainability criteria, including effluent quality, energy performance and greenhouse gas (GHG) emissions. All of these criteria were considered in the integrated plant-wide model developed in this study. The proposed model incorporates new features, including: (i) the addition of associated facilities to the overall energy balance and...
-
Isothermal Calorimetry and Compressive Strength Tests of Mortar Specimens for Determination of Apparent Activation Energy
PublicationThe hydration process of cementitious materials involves a thermally activated reaction that depends on the composition of the mixture and the curing temperature. The main parameter affecting the temperature variation of cast-in-place concrete is the apparent activation energy, which can be used for the efficient prediction of the temperature evolution and maturity index of hardening concrete. This paper discusses two methods to...
-
Breastfeeding as a regulating factor of the development of the intestinal microbiome in the early stages of life
PublicationSince the first bacterial inhabitants of the human gastrointestinal tract were identified, a lot of research into the study of the human microbiome and its effects on health has been conducted. Currently, it is accepted that humans have a symbiotic relationship with the gut microbiome, though the specifics of this relationship are not well understood. The microbiome of neonates constantly changes and appears to influence many facets...
-
Optimization of the UNRES Force Field by Hierarchical Design of the Potential-Energy Landscape. 2. Off-Lattice Tests of the Method with Single Proteins
Publication -
Growth, Crystal Structure and Magnetic Characterization of Zn-Stabilized CePtIn4
PublicationThe growth and characterization of CePtIn4, stabilized by 10% Zn substitution for In, is reported. The new material is orthorhombic, space group Cmcm (No. 63), with lattice parameters a = 4.51751(4) Å, b = 16.7570(2) Å, and c = 7.36682(8) Å, and the refined crystal composition has 10% of Zn substituted for In, i.e., the crystals are CePt(In0.9Zn0.1)4. Crystals were grown using a self-flux method: only growths containing Zn yielded...
-
Perturbation analysis of electric field around objects in sea water
PublicationThe paper presents an analytical approach to the perturbation analysis of electric field distribution caused by a sphere and an ellipsoid placed in a uniform electric field.
-
Conversion of waste biomass into activated carbon and evaluation of environmental consequences using life cycle assessment
PublicationIn this article, activated carbon was produced from Lantana camara and olive trees by H3PO4 chemical activation. The prepared activated carbons were analyzed by characterizations such as scanning electron microscopy, energy-dispersive X-ray spectroscopy, Brunauer–Emmett–Teller, X-ray diffraction, thermogravimetric analysis, and Fourier transform infrared spectroscopy. H3PO4 is used as an activator agent to create an abundant pore...
-
Green, blue and energy in cities
PublicationThe article refers to the implementation of blue-green infrastructure in cities, with particular emphasis on the aspect of rainwater and energy management. The article presents the advantages of water and greenery in the city and gives examples of engineering solutions used, both the more popular (including green and biosolar roofs), as well as experimental solutions, which are an interesting and necessary alternative in the era...
-
Determination of high-intensity sweeteners in beverages by high-performance liquid chromatography with mass spectrometry detection.
PublicationThe objective of the present study was to measure the concentration of nine high intensity sweeteners (acesulfame-K, aspartame, alitame, cyclamate, dulcin, neohesperidin dihydrochalcon, neotame, saccharin and sucralose) in different types of beverages available on the polish market. The proposed methodology reported here consists of a extraction with buffer composed of formic acid and N,N-diisopropylethylamine (pH 4.5) followed...
-
Thermodynamic analysis of the Compressed Air Energy Storage system coupled with the Underground Thermal Energy Storage
PublicationImprovement of flexibility is one of the key challenges for the transformation of the Polish Power System aiming at a high share of renewable energy in electricity generation. Flexible and dispatchable power plants will contribute to this ongoing transformation process as they compensate for fluctuations in electricity generation from renewable energy sources such as wind and photovoltaics. In this context, CAES storage tanks are...
-
Fatigue investigation of plain journal bearings
PublicationW artykule przedstawiono wybrane wyniki badań nad wytrzymałością zmęczeniową warstw ślizgowych w panwiach łozysk poprzecznych, prowadzonych w laboratorium tribologicznym Katedry Konstrukcji i Eksploatacji Maszyn Politechniki Gdańskiej. Opisano stanowiska badawcze i metodykę planowania eksperymentów oraz procedurę opracowywania wyników testów zmęczeniowych. Przedstawiono zamierzenia badawcze w zakresie przedmiotowych badań zmęczeniowych.
-
Efficiency of Biomass Energy used for Heating Purposes in a Residential Building in Comparison with other Energy Sources
PublicationThis paper discusses the results of analyses investigating the energy efficiency of biomass in comparison with other popular energy carriers used for heating, ventilation and water heating in residential buildings. The compared energy sources were lignite, natural gas, heating oil and electricity produced by conventional and integrated power generation plants. The most efficient variant relying on biomass and the least efficient...
-
Topography measurement methods evaluation for entire bending-fatigued fracture surfaces of specimens obtained by explosive welding
PublicationIn this paper, the methods of compensation of differences in the results of entire bending-fatigued fracture surface topographies were presented. The roughness evaluation was performed with a focus variation microscope and confocal surface topography measurement techniques. The differences in the ISO 25178 roughness parameters were investigated and procedures for their compensation were studied. It was found that various types...
-
Atmospheric degradation mechanism of anthracene initiated by OH•: A DFT prediction
PublicationDensity functional theory (DFT) calculations at the M06-2X/def2-TZVP level have been employed to investigate the atmospheric oxidation mechanism of anthracene (ANT) initiated by HO•. Direct hydrogen atom abstraction from the ANT using HO• takes place hardly at ambient conditions while the addition of HO• to the C1, C2, and C4 sites are thermodynamically and kinetically more advantageous. The addition reactions are controlled by...
-
Determination of Heavy Metals Concentration in Water and Soil at Various Locations in Lahore and their Harmful Impacts on Human and Plants life
PublicationHeavy metals poisoning of soil and water has resulted from industrial expansion in Lahore, Pakistan, creating a significant environmental hazard. As a result, monitoring the contamination of soil and water around industrial sites is critical. The fact that higher concentrations of heavy metals have a negative influence on both plants and human life and this cannot be ignored. Higher heavy metal concentrations have a direct impact...
-
Energy-Aware High-Performance Computing: Survey of State-of-the-Art Tools, Techniques, and Environments
PublicationThe paper presents state of the art of energy-aware high-performance computing (HPC), in particular identification and classification of approaches by system and device types, optimization metrics, and energy/power control methods. System types include single device, clusters, grids, and clouds while considered device types include CPUs, GPUs, multiprocessor, and hybrid systems. Optimization goals include various combinations of...
-
Performance Modeling and Prediction of Real Application Workload in a Volunteer-based System
PublicationThe goal of this paper is to present a model that predicts the real workload placed on a volunteer based system by an application, with incorporation of not only performance but also availability of volunteers. The application consists of multiple data packets that need to be processed. Knowing the computational workload demand of a single data packet we show how to estimate the application workload in a volunteer based system. Furthermore,...
-
FFT analysis of temperature modulated semiconductor gas sensor response for the prediction of ammonia concentration under humidity interference
PublicationThe increasing environmental contamination forces the need to design reliable devices for detecting of the volatile compounds present in the air. For this purpose semiconductor gas sensors, which have been widely used for years, are often utilized. Although they have many advantages such as low price and quite long life time, they still lack of long term stability and selectivity. Namely, environmental conditions have significant...
-
Assessment of Thermal Stresses in Asphalt Mixtures at Low Temperatures Using the Tensile Creep Test and the Bending Beam Creep Test
PublicationThermal stresses are leading factors that influence low-temperature cracking behavior of asphalt pavements. During winter, when the temperature drops to significantly low values, tensile thermal stresses develop as a result of pavement contraction. Creep test methods can be suitable for the assessment of low-temperature properties of asphalt mixtures. To evaluate the influence of creep test methods on the obtained low-temperature...
-
Measurement of expenditure efficiency of Polish cities with county rights in the context of quality of life
PublicationThe article is devoted to the measurement of efficiency of overall expenditures. The purpose of the study is to evaluate the efficiency of use of budget resources by local government units in the context of fostering quality of life. The subject of the study is 65 Polish cities with county rights (county status). Calculations were carried out using Data Envelopment Analysis (DEA). The results of analysis confirm the two research...
-
Promotion of MXene (Ti3C2Tx) as a robust electrocatalyst for oxygen evolution reaction via active sites of ZIF-67 - In situ mechanism investigations
Publication -
Flavin mononucleotide fluorescence intensity decay in concentrated aqueous solutions
PublicationCzasowo-rozdzielone widma absorpcji i fluorescencji FMN w roztworach wodnych zostały zmierzone dla szerokiego zakresu stężeń. Pokazano, że zaniki fluorescencji są silnie przyśpieszone przez obecność dimerów FMN, które stanowią niedoskonałe pułapki energii wzbudzenia. Wyniki doświadczalne porównano z rezultatami symulacji Monte-Carlo, uwzględniającej powrotny transfer energii od pułapek do donorów, stwierdzając dobrą zgodność modelu...
-
Investigation of the underwater noise produced by ships by means of intensity method
Publication -
Influence of bitumen type on cracking resistance of asphalt mixtures used in pavement overlays
PublicationCracking is one of the predominant distresses occurring in flexible pavements, especially in old pavements that were rehabilitated with an asphalt overlay. In such cases asphalt mixtures should be designed to ensure high resistance to reflective cracking because new asphalt layers are exposed to existing cracks of the old pavement. The nature of these cracks can be various (transverse, longitudinal as well as crazy cracking). One...
-
Field measurements
PublicationThe article presents the scope and methodologies used in the course of geodetic measurements accompanying archaeological excavations in the area of the Wisłoujście Fortress in Gdańsk
-
The impact of gasification wastewater on soil microorganisms and the growth of oat and red clover
Publication -
Attitude towards cigarette or e-cigarette use and the smoking initiation year among young European adults
Publication -
Justifying the prolongation of the service life of the bearing structure of a tank car when using Y25 bogies
PublicationThis paper substantiates the use of Y25 bogies under tank cars in order to prolong their service life. The reported study has been carried out for a tank car with rated parameters, as well as the actual ones, registered during full-scale research. Mathematical modeling was performed to determine the basic indicators of the tank car dynamics. The differential equations of motion were solved by a Runge-Kutta method using the Mathcad...
-
Comparative Analysis of CpG Sites and Islands Distributed in Mitochondrial DNA of Model Organisms
Publication