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Simulation of the response of base-isolated buildings under earthquake excitations considering soil flexibility
PublicationThe accurate analysis of the seismic response of isolated structures requires the incorporation of the flexibility of supporting soil. However, it is often customary to idealize the soil as rigid during the analysis of such structures. In the present paper, seismic response time history analyses of base-isolated buildings modelled as single degree-of-freedom (SDOF) and multi degree-of-freedom (MDOF) systems with linear and nonlinear...
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Buckling of braced frames
PublicationIn this paper the classical Winter model, developed originally for columns is applied for frame structures and compared with the results of parametric study of frame with bracing. Sensitivity analysis of critical loads of frame due to bracing stiffness is carried out and the threshold bracing stiffness for full bracing is found. In the non-linear statical analysis the forces in bracings are calculated.
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Frequently updated noise threat maps created with use of supercomputing grid
PublicationAn innovative supercomputing grid services devoted to noise threat evaluation were presented. The services described in this paper concern two issues, first is related to the noise mapping, while the second one focuses on assessment of the noise dose and its influence on the human hearing system. The discussed services were developed within the PL-Grid Plus Infrastructure which accumulates Polish academic supercomputer centers....
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A versatile and convenient preparation of unsymmetrical diaryl disulfides
PublicationWe have developed a convenient method for the synthesis of unsymmetrical diaryl disulfides under mild conditions in excellent yields. The described method is based on the straightforward preparation of 5,5-dimethyl-2-thioxo-1,3,2-dioxaphosphorinane-2-sulfenyl bromide from readily available 5,5-dimethyl-2-thiolo-2-thioxo-1,3,2-dioxaphosphorinane or bis(5,5-dimethyl-2-thioxo-1,3,2-dioxaphosphorinan-2-yl) disulfide. The unsymmetrical...
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Synthesis and biological activity of mycophenolic acid-amino acid derivatives
PublicationIn search of new immunosuppressants, mycophenolic acid (MPA) was coupled with amino acid methyl esters followed by hydrolysis to analogs bearing free carboxylic groups. The obtained compunds were tested in vitro as growth inhibitors of lymphoid cell line (Jurkat) and human peripheral blood mononuclear cells (PBMC) from healthy donors. According to obtained results recovering of free carboxylic group increased their activity. Additionally,...
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Numerical modelling and experimental verification of compressible squeeze film pressure
PublicationThe validity of using the Reynolds equation for compressible squeeze film pressure was tested with computational fluid dynamics (CFD). A squeeze film air bearing was instrumented with pressure sensors and non-contacting displacement probes to provide transient measurements of film thickness and pressure. The film thickness measurements also provided input parameters to the numerical prediction. However, numerical results showed...
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Influence of Gaps’ Geometry Change on Leakage Flow in Axial Piston Pumps
PublicationAxial piston pumps are the core elements of most medium and high-pressure hydraulic systems. High volumetric efficiency and high working pressures are the main advantages of this type of pumps. Therefore it is necessary to accurately calculate the leakage flow through the gaps to design efficient high-pressure pump. The main difficulty of such calculations is the fact, that the gaps change their geometry during pumping process....
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FIReWORK: FIR Filters Hardware Structures Auto-Generator
PublicationThe paper presents application called FIReWORK, that allows for automatic creation of the VHDL hardware structures of FIR filters. Automat- ically generated specialized hardware solutions dedicated to the FPGA and ASIC are commonly known as Intellectual Property Cores. The essential fu- ture of the application is easy initialization of FIR filter parameters in GUI, and then automatically design, calculate and generate the IP Core...
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Odmienność zachowania energetycznego silnika hydraulicznego liniowego - siłownika.
PublicationSilniki hydrauliczne liniowe - siłowniki, ze względu na zastosowane w ich konstrukcji uszczelnienia ruchowe, wykazują odmienne zachowanie energetyczne w porównaniu z silnikami obrotowymi. Przeprowadzone badania laboratoryjne wykazują kluczowe znaczenie struktury sterowania dławieniowego na wielkość strat tarcia w siłowniku. W pracy przedstawiono wyniki badań siłownika zasilanego w trzech strukturach sterowania dławieniowego szeregowego,...
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Wymiana ciepła w rozwiniętym filmie laminarnym powstałym z uderzenia strugi o powierzchnię.
PublicationZaproponowano prosty model wymiany ciepła w cienkich filmach cieczowych powstałych w wyniku uderzenia strug o powierzchnię. W modelu uwzględniono zminę grubości filmu cieczowego w przypadku braku oraz obecności sił bezwładności. Wyznaczono rozkłady prędkości i temperatury w filmie cieczowym, co umożliwiło obliczenie współczynników przejmowania ciepła odpowiadających tym przypadkom. Model oparty jest na rozwiązaniu równań masy,...
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Analysis of the Accuracy of Pulse Estimation Using Smart Watches
PublicationThe 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...
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Working Conditions in Global Value Chains: Evidence for European Employees
PublicationThis article investigates a sample of almost nine million workers from 24 European countries in 2014 to conclude how involvement in global value chains (GVCs) affects working conditions. We use employer–employee data from the Structure of Earnings Survey merged with industry-level statistics on GVCs based on the World Input-Output Database. Given the multidimensional nature of the dependent variable, we compare estimates of the...
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Difference in Perceived Speech Signal Quality Assessment Among Monolingual and Bilingual Teenage Students
PublicationThe user perceived quality is a mixture of factors, including the background of an individual. The process of auditory perception is discussed in a wide variety of fields, ranging from engineering to medicine. Many studies examine the difference between musicians and non-musicians. Since musical training develops musical hearing and other various auditory capabilities, similar enhancements should be observable in case of bilingual...
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System Supporting Speech Perception in Special Educational Needs Schoolchildren
PublicationThe system supporting speech perception during the classes is presented in the paper. The system is a combination of portable device, which enables real-time speech stretching, with the workstation designed in order to perform hearing tests. System was designed to help children suffering from Central Auditory Processing Disorders.
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Zastosowanie spowalniania wypowiedzi w celu poprawy rozumienia mowy przez dzieci w szkole
PublicationThis paper presents a time-scale modification algorithms that could be used for hearing impairment therapy supported by real-time speech stretching. In this paper the OLA based algorithms and Phase Vocoder were described. In the experimental part usability of those algorithms for real-time speech stretching was discussed
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4D Reconstruction and Visualisation of Krakow Fortress
PublicationThe specific aim of the European project named "Cultural Heritage Through Time" (CHT2) and reported in this paper is to fully integrate the fourth dimension (4D) into Cultural Heritage studies for analysing structures and landscapes over time. Krakow-the Fortress City (Poland) is the one of four case studies of the CHT2, which are used for the time varying reconstruction, analysis, visualization, and preservation. The goal of...
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Normal stress distribution in built‑up cold‑formed column in relation to interconnecting bolt spacing
PublicationIn order to increase a stiffness of cold-formed steel (CFS) elements it is practised to built-up the cross-section. In the analysed case, a main element is strengthened by adding extra chord in contact partially along the column. This additional chord acts as a longitudinal stiffener connected with the main section by series of bolts. Authors check whether rules applied over the years, for hot-rolled elements, can be indiscriminately...
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The use of a 4 PB strain sweep fatigue test to evaluate characteristics of carbon grid reinforced asphalt beams
PublicationThe article presents research results concerning pre-bituminized carbon grids for asphalt pavement reinforcement, which are used to prevent cracking and crack reflection thus increasing bearing capacity and durability of pavement. Research program involved testing of large sized double-layer samples, both reinforced and unreinforced. The advantage of using a carbon grid was especially visible after crack initiation. The energy...
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Catalytic Asymmetric Synthesis of Isochroman Derivatives
PublicationThe isochroman scaffold constitutes an important structural unit, which is present in various bioactive natural products and synthetic pharmaceutical compounds exhibiting wide arrays of biological properties. Hence the synthesis of this class of heterocyclic compounds in a stereoselective fashion is highly significant and desirable. In the last decade, a substantial advancement has been witnessed ln the catalytic asymmetric...
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The influence of anchoring group position in ruthenium dye molecule on performance of dye-sensitized solar cells
PublicationThe effect of anchoring group position and, in consequence, the orientation of the ruthenium dye molecule on titania surface on the performance of dye-sensitized solar cells has been studied intensively. Three model ruthenium sensitizing dyes bearing carboxylic anchoring group in ortho, meta or para position were synthesized and well characterized by spectroscopic, electrochemical, photophysical and photochemical measurements....
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Analysis of Ceramic Elements with Ring-Crack Defects in Lubricated Rolling Contact
PublicationThe properties of ceramics, specifically low density, high hardness, high temperature capability and low coefficient of thermal expansion are of most interest to rolling element manufacturers. Surface ring cracks on lubricating rolling contact fatigue failure has been studied using numerical fracture analysis. Such cracks are very often found on ceramic bearing balls and decrease fatigue life rapidly. The numerical calculations...
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Fundamenty palowe, obliczenia z zastosowaniem zasad Eurokodu 7 i doświadczeń krajowych
PublicationPrzedstawiono zagadnienia obliczania fundamentów palowych w nawiązaniu do zaleceń Eurokodu 7. Zwrócono uwagę, że zgodnie z założeniami Eurokodu 7, projektant i inżynier ma swobodę w wyborze metod obliczeniowych.Przytoczono i zarekomendowano metody i propozycje miedzy innymi obliczania statycznego układów palowych, określania nośności pali, prognozowania osiadań fundamentów palowych oraz charakterystyk obciążenie-osiadanie pali...
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Możliwości stosowania układów absorpcyjnych w racjonalnej gospodarce energetycznej
PublicationKierunki rozwoju nowoczesnej energetyki cieplnej określają europejskie dyrektywy, które promują nowoczesne rozwiązania. Racjonalna gospodarkę energetyczna wymaga ograniczenia strat energii poprzez pełniejsze jej wykorzystanie. Dobrym tego przykładem jest gospodarka skojarzona w która dobrze wpisują się układy absorpcyjne. W artykule ukazano ekonomiczną efektywność takich rozwiązań oraz potrzebę wykorzystania urządzeń absorpcyjnych...
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Układy sterowania bramkowego tranzystorów z węglika krzemu SiC JFET w falownikach napięcia
PublicationZastosowanie technologii węglika krzemu (SiC) w falownikach napięcia pozwala na zwiększenie częstotliwości przełączeń oraz temperatury pracy przyrządów półprzewodnikowych. W celu zapewnienia minimalizacji strat oraz określonych właściwości dynamicznych tranzystorów z węglika krzemu wymagane jest stosowanie zaawansowanych układów sterowania bramkowego. W referacie przedstawiono analizę teoretyczną, wyniki badań symulacyjnych oraz...
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Optymalizacja rozpływów mocy biernej w systemie elektroenergetycznym
PublicationReferat prezentuje zagadnienia związane ze sterowaniem poziomami napięć w systemie elektroenergetycznym. Rozważane są dwie metody optymalizacji rozpływu mocy biernej, prowadzące do poprawy warunków napięciowych w systemie elektroenergetycznym i ograniczenia strat mocy czynnej. Pierwsza z metod optymalizacyjnych poddanych weryfikacji została zaimplementowana w programie PLANS, a bazuje na autorskiej procedurze opartej o logikę rozmytą,...
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Uzyskanie standardu pasywnego
PublicationCelem artykułu jest ocena budynku mieszkalnego w zabudowie bliźniaczej w świetle obowiązujących przepisów dotyczących energooszczędności oraz analiza czasów i kosztów jego wykonania w dwóch wariantach klasy energetycznej. W ramach analizy wyliczono bilans strat oraz zysków ciepła, na podstawie którego utworzono wskaźniki charakterystyczne. Następnie zaproponowano rozwiązania pozwalające obniżyć te wskaźniki do poziomu dopuszczalnych...
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Badania podwójnego izolatora wykorzystujacego złącza ferrytowych sprzężonych linii mikropaskowych
PublicationW niniejszej pracy zbadano możliwości realizacji układu warstwowego izolatora podwójnego. Układ taki jest kaskadowym połączenie dwóch izolatorów wykonanych z cyrkulatorów FCL(Ferrite Coupled Line) zrealizowanych w technice linii mikropaskowych. W ramach przeprowadzonych badań wykonano projekty sekcji FCL oraz pozostałych układów tworzących układ izolatora, a następnie wyznaczono jego charakterystyki rozproszenia. Uzyskane numerycznie...
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Dietary intervention with beetroot juice during doxorubicin cancer chemotherapy in vivo reduces markers of oxidative stress
PublicationCancer chemotherapy with doxorubicin, despite high antitumor activity and broad spectrum of this drug, is on decline due to toxic side effects. The clinical efficacy of anthracyclines have continuously prompted the search for new adjuvants to alleviate undesirable side toxicity incurred by this group of cytostatics. The recent approaches involve the application of synthetic or purified natural antioxidants in combination with doxorubicin...
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Alphitobius diaperinus larvae (lesser mealworm) as human food – An approval of the European Commission – A critical review
PublicationDue to the increasing threat of climate change and the need for sustainable food sources, human consumption of edible insects or entomophagy has gained considerable attention globally. The larvae of Alphitobius diaperinus Panzer (Coleoptera: Tenebrionidae), also known as the lesser mealworm, have been identified as a promising candidate for mass-rearing as a food source based the on evaluation on several aspects such as the production...
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Impact of reclaimed asphalt pavement (RAP) on low-temperature properties of asphalt concrete
PublicationHot mix recycling is a practice which enables reusing materials from old asphalt pavements. Current Polish regulations allow usage of RAP only for binder and base courses, and its amount is limited. Asphalt mixtures with RAP material have to fulfil requirements stated for typical asphalt mixtures. The research presents low-temperature properties of twelve different asphalt concretes with RAP material, determined using three-point...
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Non-linear behaviour of base-isolated building supported on flexible soil under damaging earthquakes
PublicationSeismic isolation is a strategy to reduce damage of structures exposed to devastating earthquake excitations. Isolation systems, applied at the base of buildings, lower the fundamental frequency of the structure below the range of dominant frequencies of the ground motion as well as allow to dissipate more energy during structural vibrations. The effectiveness of the base-isolated buildings in damage reduction has been confirmed...
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Application of Shape Memory Alloys in Pipeline Couplings for Shipbuilding
PublicationThe aim of the study is to analyse shape memory alloy (SMA) pipeline joints in limited space applications for all kinds of ships. Generally, the space available in various areas on ships is strictly limited and service works usually meet many obstacles. If we consider a pipeline, the flange joints always require a larger free space around the pipe than the pipe alone. A simultaneous problem can occur with the propeller shaft line...
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Numerical analysis of crack propagation in silicone nitride
PublicationThe properties of ceramics, specifically low density, high hardness, high temperature capability and low coefficient of thermal expansion are of most interest to rolling element manufacturers. The influence of ring crack size on rolling contact fatigue failure has been studied using numerical fracture analysis. Such cracks are very often found on ceramic bearing balls and decrease fatigue life rapidly. The numerical calculation...
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Simple colorimetric copper(II) sensor – spectral characterization and possible applications
PublicationNew o-hydroxyazocompound L bearing pyrrole residue was obtained in the simple synthetic protocol. The structure of L was confirmed and analyzed by X-ray diffraction. It was found that new chemosensor can be successfully used as copper(II) selective spectrophotometric regent in solution and can be also applied for the preparation of sensing materials generating selective color signal upon interaction with copper(II). Selective colorimetric...
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ANALYSIS OF BRACE STIFFNESS INFLUENCE ON STABILITY OF THE TRUSS
PublicationThe paper is devoted to the numerical and experimental research of stability of a truss with side elastic supports at the top chord. The structure is a model of a real roof truss scaled by factor ¼. The linear buckling analysis and non-linear static analysis were carried out. The buckling length factor for the compressed top chord was calculated and the limit load for the imperfect truss shell model with respect to brace stiffness...
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Experimental Tests Of Sandwich Beams In The Design Process Of GFRP Shell Footbridge Structure
PublicationThe paper includes selected aspects of the study to elaborate architectural, material and construction design of pedestrian footbridge spans made of composite materials. The considered footbridge is a sandwich-type shell structure. The cooperation of PET foam core with outer lining surfaces is crucial for its load bearing capacity. The paper is aimed to experimental investigation of sandwich beams subjected to bending loading....
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Resonant DC link inverters for AC motor drive systems – critical evaluation
PublicationIn this survey paper, resonant and quasiresonant DC link inverters are reexamined for AC motor drive applications. Critical evaluation of representative topologies is based on simulation and waveform analysis to characterize current/voltage stress of components, control timing constraints and feasibility. A special concern over inverter common-mode voltage and voltage gradient du/dt limitation capacity is discussed for motor bearing...
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Metodyka projektowania łożysk ślizgowych z tamą hydrodynamiczną.
PublicationW artykule przedstawiono nową metodykę projektowania poprzecznych łożysk ślizgowych z tamą hydrodynamiczną. Zaproponowana metoda pozwala na wyznaczanie charakterystyk statycznych i dynamicznych dowolnych łożysk poprzecznych, w których wykonano jedną lub wiele tam hydrodynamicznych. W omawianej metodzie wykorzystano dwa niezależne programy komputerowe (BEARing i ArtBEAR). W celu oszacowania dokładności wybranej metody wykonano obliczenia...
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Analiza czynników niskotemperaturowych do instalacji grzewczej w jednorodzinnym budynku mieszkalnym
PublicationW niniejszej pracy przeprowadzono analizę projektową instalacji grzewczej opartej na sprężarkowej pompie ciepła. Instalacja ta zasila systemy centralnego ogrzewania i przygotowania ciepłej wody użytkowej w jednorodzinnym budynku mieszkalnym znajdującym się w miejscowości Koleczkowo. W analizie zawarto ocenę strat i zysków cieplnych budynku, obliczenia zapotrzebowania na moc cieplną analizowanego obiektu oraz koncepcyjne rozwiązania...
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Analiza wpływu wybranych odnawialnych źródeł energii na straty mocy czynnej i biernej w systemie elektroenergetycznym
PublicationMoc zainstalowana oraz produkcja energii elektrycznej z odnawialnych źródeł energii od kilkunastu lat systematycznie w Polsce wzrasta. Należy spodziewać się, że tendencja ta w najbliższych latach zostanie utrzymana. Dość dużym zainteresowaniem cieszą się źródła wiatrowe oraz źródła fotowoltaiczne, co sprawia, że przy znacznych ich mocach zainstalowanych konieczne staje się badanie wpływu tych źródeł na system elektroenergetyczny....
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Some approaches to the determination of saw blade stiffness.
PublicationW nowoczesnych zakładach przerobu drewna obserwuje się tendencję do redukcji rzazu w celu ograniczenia strat surowca. Jednakże, cienkie piły są bardziej wrażliwe na odziaływanie sił odporowych (bocznych). Dlatego też, znajomość sztywności statycznej pozwala użytkownikowi prognozować zachowanie się piły podczas pracy. W pracy przedstawiono metodykę wyznaczania sztywności statycznej początkowej i roboczej pił trakowych oraz taśmowych....
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Redevelopment of Gdynia waterfront - students' imagination
PublicationThe article presents the ideas of Gdynia waterfront redevelopment, proposed by students of the Faculty of Architecture, as diploma works. Gdynia is often a subject of diploma works - as a city of many needs, opportunities and challenges. It gives students the wide range of possibilities to create attractive, modern and unique development – concerning different functions, forms and meanings. Students works have been presented regarding...
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Low-coherence sensors with nanolayers for biomedical sensing
PublicationIn this paper, we describe the fiber optic low-coherence sensors using thin film. We investigated their metrological parameters. Presented sensors were made with the use of standard telecommunication single mode optical fiber (SMF28). Different materials were applied to obtain thick layers, such as boron doped diamond, silver and gold. The thickness of layers used in the experiments ranged from 100 nm to 300 nm. Measurements were...
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Screw displacement pile shaft deformations measured by vibrating wire and fiber optic systems during a static load test
PublicationThis paper describes a full scale static load test performed on a 400 mm diameter screw displacement pile equipped with four different strain measuring systems. Three types of vibrating wire strain gauges (VWSG) were used: global - retrievable, local attached to steel pipe and local concrete embedded. The fourth system was distributed fiber optic sensors based on Rayleigh back scattering (DFOS) - three in the pile cross section....
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Metoda i algorytmy modyfikacji sygnału do celu wspomagania rozumienia mowy przez osoby z pogorszoną rozdzielczością czasową słuchu
PublicationPrzedmiotem badań przeprowadzonych w ramach rozprawy są metody modyfikacji czasu trwania sygnału (ang. Time Scale Modification –TSM) mowy operujące w czasie rzeczywistym oraz ocena ich wpływu na rozumienie wypowiedzi przez osoby z pogorszoną rozdzielczością czasową słuchu. Pogorszona rozdzielczość słuchu jest jednym z symptomów związanych z ośrodkowymi zaburzeniami słuchu (ang. Cetnral Auditory Processing Disorder – CAPD). W odróżnieniu...
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Engineering Challenges in the Design of Cochlear Implants
PublicationHearing aids such as cochlear implants have been used by both adults and children for a long time. In addition, cochlear implants are used by patients who have severe hearing loss either by birth or after an accident. This paper aims to investigate the engineering challenges bounding the design of cochlear implants and present its possible solution...
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Approaches Towards Better Immunosuppressive Agents
PublicationSeveral classes of compounds are applied in clinics due to their immunosuppressive properties in transplantology and the treatment of autoimmune diseases. Derivatives of mycophe-nolic acid, corticosteroids and chemotherapeutics bearing heterocyclic moieties like methotrexate, azathioprine, mizoribine, and ruxolitinib are active substances with investigated mechanisms of action. However, improved synthetic approaches of known drugs...
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Study on 19th-century cast iron columns from the former financial office building in Kwidzyn
PublicationThe article presents the results for cast iron columns used as floor supports in the former financial office building in Kwidzyn (Poland).The stocktaking drawings provided the general and detailed data about the 19th century designer’s decisions. During the research, architectural and structural analysis was carried out. The graphics were used as a starting material for preparing 3D calculation models. The FEM-based numerical simulations...
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Improvement of the load capacity of the road overpass as a result of repairs after breakage caused by vehicle impacts
PublicationDamage of spans of the overpass caused by impact of underpassing vehicles are a frequent case. Objects that use prefabricated load-bearing elements that are not designed for such impacts are particularly exposed. After impact, such parts suffer extensive damage that need repair. Taking advantages of this recovery actions it is worth to perform strengthening that will protect object against possible future impacts. In this study...
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The mechanism of grouting action under the base of bored pile
PublicationThe grouting under the base of bored pile is carried out in order to reduce pile settlement and improve its bearing capacity. The principal aim of grouting is to introduce an initial force between the soil and the pile base. In non-cohesive soil, the grouting can also enlarge the pile base area and therefore improve the base resistance. The example of static load tests on instrumented bored piles installed with and without grouting...