Filtry
wszystkich: 3299
wybranych: 1647
-
Katalog
Filtry wybranego katalogu
wyświetlamy 1000 najlepszych wyników Pomoc
Wyniki wyszukiwania dla: FEAR OF CHILDBIRTH
-
Sliding Wear Performance of AlCrN Coating on TiB2/Ti Composites at High Temperatures
Publikacja -
The Effect of WC/C Coating on the Wear of Bevel Gears Used in Coal Mines
Publikacja -
Spatio-Temporal Variation in Predation on Artificial Ground Nests: A 12-Year Experiment
Publikacja -
2D numerical simulation of tear film dynamics: Effects of shear-thinning properties
Publikacja -
A Study on Emission of Airborne Wear Particles from Car Brake Friction Pairs
PublikacjaThe emission of airborne wear particles from friction material / cast iron pairs used in car brakes was investigated, paying special attention to the influence of temperature. Five low-metallic materials and one non-asbestos organic material were tested using a pin-on-disc machine. The machine was placed in a sealed chamber to allow airborne particle collection. The concentration and size distribution of 0.0056 to 10 μm particles...
-
Quantification of ultrafine airborne particulate matter generated by the wear of car brake materials
PublikacjaThe wear of car brakes is one of the main sources of airborne particulate matter in urban environments. Ultrafine wear particles are of special environmental interest since they can easily penetrate the human body through inhalation and cause various diseases. In the present study, the contribution of ultrafine particles to airborne particulate matter emitted from car brake materials was investigated under different friction conditions....
-
Mechanical Properties and Sliding Wear Resistance of Suspension Plasma Sprayed YSZ Coatings
Publikacja -
An evaluation of endemic exposure of citizens living in near a Gdańsk Phosphatic Fertilizer Plant
PublikacjaPrzeprowadzono ocenę wpływu Gdańskich Zakładów Nawozów Fosforowych FOSFORY na mieszkańców różnych dzielnic Gdańska. Oznaczono - za pomocą Neutronowej Analizy Aktywacyjnej (NAA) stężenia Al, As, Au, Br, Ca, Cl, Cu, Dy, I, In, K, La, Mg, Mn, Mo, Na, S, Sb, Sm, U, V, Zn w próbkach włosów i paznokci stóp, zebranych od 22 osób mieszkających w sąsiedztwie Zakładów oraz od jedenastoosobowej grupy kontrolnej. Podstawowe różnice pomiędzy...
-
Wear estimation of current collector contact strips by analysis of a 3D scanning results
PublikacjaThe technical condition of current collector contact strips is very important when operational reliability of railway transportation is considered. The authors proposed a novel measurement system based on a 3D camera to register the shape and dimensions of the current collector contact strips surface. The system was installed above the railway track for tests in target ambient. During the trial operation a few dozen of contact...
-
Reclamation of phosphogypsum deposition site Wiślinka near Gdańsk with municipal sewage sludge.
PublikacjaOmówiono zastosowanie osadów ściekowych do rekultywacji składowiska fosfogipsów w Wiślince k. Gdańska. Głównie pojawiają się problemy ze stabilizacją stoków oraz z sukcesją roślinności i zwalczaniem erozji wiatrowej.
-
Wear and corrosion characteristics of the layers type (mn-p) formed on aluminium alloys
Publikacjaopisano multipleksową metodę wytwarzania warstw zawierających mangan i fosfor (mn-p) na stopach aluminium. przedstawiono wyniki badań mikrostruktury, właściwości tribologicznych i korozyjnych tych warstw. stwierdzono obecność tlenku manganu i fosforku manganu w wytworzonych warstwach oraz ich wysoką twardość, rzędu 1272 hv0,02. warstwy typu (mn-p) zmniejszają podatność stopu alsi13mg1cuni na korozję w 0,01 mh2so4.
-
Influence of geometrical and operational parameters on tooth wear in the working mechanism of a satellite motor
PublikacjaThis article describes the phenomena affecting the wear of the rotor of the working mechanism in a hydraulic satellite motor. The basic geometrical relationships that allow the calculation of the coordinates of the points of contact between the satellite and the rotor and the curvature are presented. A method for calculating the number of contacts of the satellite teeth with the rotor teeth and of the satellite teeth with the curvature...
-
MAPPING SOUTH BALTIC NEAR-SHORE BATHYMETRY USING SENTINEL-2 OBSERVATIONS
PublikacjaOne of the most promising new applications of remote observation satellite systems (RO) is the near-shore bathymetry estimation based on spaceborn multispectral imageries. In recent years, many experiments aiming to estimate bathymetry in optically shallow water with the use of remote optical observations have been presented. In this paper, optimal models of satellite derived bathymetry (SDB) for relatively turbid waters of the...
-
Ship course control system taking into account the steering gear dynamic properties
PublikacjaW artykule zostały przedstawione różne konfiguracje regulatorów nieliniowych do sterowania kursem statku. Zaprojektowane regulatory oparto na metodzie backstepping, regulatorze PD oraz sterowaniu ślizgowym. Algorytmy uwzględniają na etapie projektowania liniowe własności dynamiczne urządzenia wykonawczo - sterującego maszyny sterowej. Dokonano analizy porównawczej jakości pracy rozpatrywanych struktur sterowania podczas badań symulacyjnych...
-
Evaluation of Wear Resistance of Ti alloys used for elements friction of knee endoprosthesis
PublikacjaThe paper presents research results of resistance to abrasive wear of titanium alloys: Ti6Al4V (commonly used) and Til3Nb13Zr (alloy of new generation) in association with polyethylene (UHMW-PE) predisposed for elements on pair of the knee endoprosthesis. The results were analysed from the point of possibility of an use of new generation titanium alloys as components of such implants. The tests of resistance to abrasive wear of...
-
Numerical and experimental investigation of thermal convection near electric devices with vertical channels
PublikacjaThis paper presents the results of numerical and experimental investigation of thermal convection near heat emitting surfaces of an electric device. For the intensification of thermal convection, special vertical channels were formed near the heat emitting surfaces of the device. An experimental test has proved that there is an optimal length of the channels – thermal convection is the most intensive then. Air velocity vectors...
-
Influence of frame sawing machine´s kinematics on saw blade tooth wear.
PublikacjaW pracy przedstawiono wpływ kinematyki pilarki ramowej na zużycie ostrzy piłtrakowych.
-
Composite sandwich footbridge—measured dynamic response vs. FEA
Publikacja -
Peripheraln regions - how far is Poland from the rest of the Europe?
PublikacjaW rodziale w monografii autorka przeprowadza analizę statystyczną w celu oszacowania dystansu dzielącego Polskę od krajów Europy. W analizie wzięto pod uwagę dane z lat 2000-2008 w celu oceny zmiany pozycji Polski w Europie pod względem poziomu rozwoju społecznego i ekonomicznego.
-
On geometrically non-linear FEA of laminated FRP composite panels
PublikacjaThe paper presents a state-of-art review on Finite Element Analysis (FEA) of geometrically non-linear problems for laminated composite plates and shells made as fibre reinforced polymer (FRP) laminates. Besides a subjective overview of the historical development of geometrically non-linear FEA of laminated FRP composite panels, some remarks on possible future issues in this research area are given
-
Composite sandwich footbridge - measured dynamic response vs. FEA
PublikacjaThe paper describes a process of in situ dynamic tests of a composite sandwich footbridge before its accepta-tion for exploitation in real traffic conditions. It is only a part of a big research task that includes design, manufacture and introduce practical application of the bridge. The in situ measured natural modes and fre-quencies are compared with numerically determined ones. Finite element analysis is established to estimate...
-
Which Target Blood Pressure in Year 2018? Evidence from Recent Clinical Trials
Publikacja -
The impact of laser surface treatment on the microstructure, wear resistance and hardness of the AlMg5 aluminum alloy
Publikacja -
Ultraviolet to near-infrared down-conversion in Bi3+–Yb3+ co-doped YAM phosphor
Publikacja -
Safety of Bariatric Surgery in ≥ 65-Year-Old Patients During the COVID-19 Pandemic
Publikacja -
The Effect of a Gear Oil on Abrasion, Scuffing, and Pitting of the DLC-Coated 18CrNiMo7-6 Steel
Publikacja -
Amide/Amino-Based Functional Additives for Lubricants: Structure, Antimicrobial Activity and Wear Resistance
Publikacja -
Graffiti saves birds: A year-round pattern of bird collisions with glass bus shelters
Publikacja -
Patient with metastatic breast cancer presenting as acute cholecystitis with one-year survival on hormonotherapy
Publikacja -
A 5-Year Experience with Laparoscopic Adjustable Gastric Banding—Focus on Outcomes, Complications, and Their Management
Publikacja -
Creation of structures by 4, 5 and 6-year-old children, considering the conditions for the structure
Publikacja -
Increase in wear resistance of nickel plasma coatings under traditional and combined treatment conditions
Publikacja -
Use of personal knowledge of 8-year-old students in creative solving of technical tasks
Publikacja -
Arterial structure and function in subjects with acute coronary syndrome after one-year of treatment
Publikacja -
Wear Resistance Enhancement of Al6061 Alloy Surface Layer by Laser Dispersed Carbide Powders
PublikacjaIn this paper, results of the experimental study on improving wear resistance in sliding friction of Al-based alloy are presented. The technique used involves the formation of a metal matrix composite (MMC) in the alloy surface layer by laser dispersion of carbide powders such as WC, TiC and SiC. For WC and TiC MMC surface coatings fabricated under conditions typical for most of the technologically relevant solid-state lasers (wavelength...
-
Chemical, Physical, and Mechanical Properties of 95-Year-Old Concrete Built-In Arch Bridge
PublikacjaThis research aimed to determine the durability and strength of an old concrete built-in arch bridge based on selected mechanical, physical, and chemical properties of the concrete. The bridge was erected in 1925 and is located in Jagodnik (northern Poland). Cylindrical specimens were taken from the side ribs connected to the top plate using a concrete core borehole diamond drill machine. The properties of the old concrete were...
-
Methylene Blue Near-Infrared Fluorescence Imaging in Breast Cancer Sentinel Node Biopsy
PublikacjaIntroduction: Fluorescence-based navigation for breast cancer sentinel node biopsy is a novel method that uses indocyanine green as a fluorophore. However, methylene blue (MB) also has some fluorescent properties. This study is the first in a clinical series presenting the possible use of MB as a fluorescent dye for the identification of sentinel nodes in breast sentinel node biopsy. Material and methods: Forty-nine patients with...
-
Study on Dry Sliding Wear and Friction Behaviour of Al7068/Si3N4/BN Hybrid Composites
PublikacjaHybrid aluminium metal matrix composites have the potential to replace single reinforced aluminium metal matrix composites due to improved properties. Moreover, tribological performance is critical for these composites, as they have extensive application areas, such as the automotive, aerospace, marine and defence industries. The present work aims to establish the tribological characteristics of Al7068/Si3N4/BN hybrid metal matrix...
-
Tool Wear Monitoring Using Improved Dragonfly Optimization Algorithm and Deep Belief Network
PublikacjaIn recent decades, tool wear monitoring has played a crucial role in the improvement of industrial production quality and efficiency. In the machining process, it is important to predict both tool cost and life, and to reduce the equipment downtime. The conventional methods need enormous quantities of human resources and expert skills to achieve precise tool wear information. To automatically identify the tool wear types, deep...
-
Unusual dynamic properties of water near the ice-binding plane of hyperactive antifreeze protein
PublikacjaThe dynamical properties of solvation water of hyperactive antifreeze protein from Choristoneura fumiferana (CfAFP) are analyzed and discussed in context of its antifreeze activity. The protein comprises of three well-defined planes and one of them binds to the surface of ice. The dynamical properties of solvation water around each of these planes were analyzed separately; the results are compared with the dynamical properties...
-
A 95-Year-Old Concrete Arch Bridge: From Materials Characterization to Structural Analysis
PublikacjaThe structural analysis of a 95-year-old concrete arch bridge located in Jagodnik (Poland) is performed in this paper, in order to check its behavior under today’s traffic loads. The mechanical properties of both the concrete and the reinforcement are investigated by testing cores and bar stubs extracted from the bridge. Structural analysis confirms that the bridge meets today’s load requirements in terms of bearing capacity, serviceability...
-
A design concept of main propulsion system with hydrostatic transmission gear for inland waterways ship
PublikacjaCelem analizy jest przedstawienie koncepcji napędu głównego statku oraz określenie jego sprawności całkowitej. Zrealizowanie zamierzenia przedstawionego powyżej wymaga spojrzenia na opis strat i sprawności energetycznej przekładni hydrostatycznej, uwzględniający jak najdalej idącą jego prostotę. Obraz wzajemnego wpływu strat we wszystkich elementach układu hydraulicznego okazuje się bardzo złożony. Przy założeniu koniecznych uproszczeń...
-
Effect of chemical composition on corrosion and wear behaviour of the composite Ni-Fe-Al2O3 coatings.
PublikacjaPrzedstawiono wyniki badań powłoki kompozytowej otrzymanej przez osadzanie katodowe galwaniczne w roztworze zawierającym sole niklu, żelaza oraz cząstki ceramiki Al2O3 o różnej wielkości i stężeniu. Wykazano, że charakterystyka ceramiki posiada wpływ na szybkość korozji i zużycia ściernego. W szczególności, zawartość ceramiki wpływa dodatnio na odporność na zużycie ścierne, ale nieco obniża odporność na zużycie korozyjne.
-
EVALUATION OF SURFACE ROUGHNESS PARAMETERS OF TURNED GEAR WHEELS HOLES MACHINED BY BALL BURNISHING
PublikacjaW artykule zaprezentowano wyniki z badań eksperymentalnych dotyczących przygotowania powierzchni do obróbki wykończeniowej nagniataniem. Badania dotyczyły obróbki materiałów w stanie utwardzonym po hartowaniu. analizowano wpływ parametrów toczenia na twardo na uzyskiwane wartości parametrów chropowatości powierzchni jako wejściowych przed procesem nagniatania.
-
Influence of bush wear in water lubricated marine stern tube bearings with shaft misalignment
PublikacjaWater lubricated propeller shaft bearings are frequently employed on modern ships due to their advantages such as durability, simplicity and low price. Specific working conditions on ships cause shaft misalignment which often results in rapid wearing of bush and shaft. Shaft misalignment could be an effect of manufacturing or assembly faults but sometimes it appears due to hull or shaft deformation. The wearing process has influence...
-
Intensification of thermal convection near electric devices using flat screens – computer modelling
PublikacjaIntensification of natural thermal convection near electric devices is possible by application of additional elements as screens creating convection canals close to the device. In the earlier authors paper the results of the analysis of thermal convection with the use of only one additional screen close to the electric device were presented. This paper presents computer modelling of thermal convection when two screens near the...
-
Algorithm for Automatic Wear Estimation of Railway Contact Strips Based on 3D Scanning Results
PublikacjaElectric rail vehicles use current collection system which consists of overhead contact line and a current collector (pantograph) mounted on the roof of a vehicle. A pantograph is equipped with contact strips, which slide along the contact wire, ensuring steady electric contact. Contact strips are made of carbon layer, fixed to an aluminum carrier. The carbon layer wears down due to friction. Using overly worn contact strips increases...
-
Extraction of antenna pattern from near field antenna measurements distorted by undesired emission
PublikacjaIn this paper authors present experimental correction of antenna pattern obtained from near field measurements when they are distorted by determined electromagnetic emission. Such situation may be met e.g. when feeding or supply subsystem interacts with antenna radiation pattern due to self-emission. Presented results of experiments show effectiveness of extraction of antenna pattern utilizing near field antenna measurements.
-
Influence of pulse waves on the transmission of near-infrared radiation in outer-head tissue layers.
PublikacjaIn this study, we investigate the effect of pulse waves on the transmission of near-infrared radiation in the outer tissue layers of the human head. This effect is important in using optical radiation to monitor brain conditions based on measuring the transmission changes in the near-infrared radiation between the source and the detector, placed on the surface of the scalp. This is because the signal related to the changes in the...
-
Issue of changes in technical states of a diesel engiene as the result of wear of its tribological systems
PublikacjaWskazano na konieczność rozpatrywania procesów obciążeń i zużywania układów tribologicznych silników o zapłonie samoczynnym (a zatem również zmiany ich stanów) w warunkach rzeczywistych jako procesów losowych. Oznacza to, że matematycznymi modelami tych procesów mogą być funkcje losowe o argumencie, którym jest czas (t) i o wartościach, którymi są zmienne losowe takie jak obciążenia i zużycia poszczególnych układów tribologicznych....