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Search results for: HIP REPLACEMENT PROSTHESIS
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Late subclinical hemolysis and long-term outcomes after aortic valve replacement with On-X mechanical prostheses – a preliminary single-center report
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Viscoelastic lubrication of human hip joint for impulsive motion after injury. Lepkosprężyste smarowanie stawu biodrowego człowieka dla impulsywnego ruchu po urazie.
PublicationW pracy rozpatruje się urazy wywołujące zmniejszenie lub zwiększenie wysokości i zmiany kształtu szczeliny stawu, które to zmiany po pewnym określonym czasie po doznanym urazie mogą zanikać. W konsekwencji takich urazów i to w bardzo krótkim czasie rzędu mikrosekund następują bardzo istotne zmiany parametrów smarowania. Mamy tu na uwadze zmiany rozkładów wartości ciśnienia i sił nośnych. Takie zmiany warunków smarowania nieustalonego...
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Capacity and pressure calculations in hip joint for periodic stochastic effects. Obliczanie ciśnienia i nośności w stawie biodrowym dla periodycznych stochastycznych efektów.
PublicationPraca przedstawia konkretne wyniki numeryczne wartości ciśnienia i sił nośnych dla hydrodynamicznego smarowania stawu biodrowego człowieka w okresowym ruchu nieustalonym z uwzględnieniem stochastycznie zmiennej wysokości szczeliny stawu przy założeniu, że współpracujące powierzchnie głowy kostnej i panewki są całkowiecie oddzielone od siebie warstwą synowialnej cieczy smarującej. Smarowanie powierzchni stawowych odbywa się tu na...
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Unsteady periodic pressure and capacity for viscoelastic lubrication in spherical hip joint. Nieustalone okresowe ciśnienie i nośność w lepkosprężystym smarowaniu sferycznego stawu biodrowego.
PublicationNiniejsza praca przedstawia obliczenia numeryczne rozkładu wartości ciśnienia i siły nośnej podczas hydrodynamicznego smarowania w szczeliny stawu biodrowego człowieka przy uwzględnieniu okresowego ruchu niestacjonarnego oraz lepkosprężystych właściwości cieczy synowialnej, zmieniających się w czasie. Takie właściwości cieczy synowialnej nie były uwzględniane w dotychczasowych pracach naukowych przy modelowaniu numerycznym stawu...
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Comparative in vitro research of the Human Aortic Bioprosthesis
PublicationE valuate of the usefulness and reliability of structures based on the analysis of recorded parameters determining the flow through the Human Aortic Bioprosthesis (HAB) have been dealt with. By flow parameters changes determining the performance environment of prosthesis analyzed change of the motion dynamics of the valve leaflets as a function of pressure, thereby determining the degree of alignment of the prosthesis to the performance...
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The allergic and irritating reactions to metallic implants with trauma - orthopaedic patients
PublicationThe article presents the analysis of clinical operation complications after the treatment of long bones by mean of ostheosynthesis with the use of metal implants and endoprothesoplastic of hip joints.
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Biocompatibility and bioactivity of bearing loaded metallic implants
PublicationPresentation of developed titanium alloy base composite materials possessing better biocompatibility, longer lifetime and bioactivity behavior for bearing loaded implants, e.g. hip joint and knee joint endoproshtesis.
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BIOMATERIALS AND IMPLANTS IN CARDIAC AND VASCULAR SURGERY - REVIEW
PublicationCurrently, on prosthesis in cardiac blood vessels and heart valves are used materials of animal or synthetic origin. For animal materials include, among others pericardial sac in which is the heart. Materials such as this (natural) are characterized by a remarkable biocompatibility within the human body, but their main disadvantage is the relatively low durability. In turn, synthetic materials, which include the austenitic chromium-nickel-molybdenum...
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Rozmyty system wnioskowania do oszacowania maksymalnego naprężenia kontaktowego na powierzchni panewki endoprotezy stawu biodrowego w zależności od kąta Wiberga i masy ciała pacjenta = Fuzzy reasoning system for maximal contact stress estimation on acetabular surface in hip endoprosthesis based on Wiberg angle and weight of patient
PublicationPrzedstawiono możliwość wykorzystania systemu rozmytego, który wykorzystując rozumowanie przybliżone określa maksymalne naprężenie kontaktowe na powierzchni przenoszenia obciążeń panewki endoprotezy stawu biodrowego, biorąc pod uwagę kąt Wiberga oraz masę ciała pacjenta.
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Constitutive Modelling of Knitted Abdominal Implants in Numerical Simulations of Repaired Hernia Mechanics
PublicationThe paper presents a numerical approach to describe mechanical behavior of anisotropic textile material, which is a selected abdominal prosthesis. Two constitutive nonlinear concepts are compared. In the first one the material is considered composed from two families of threads (dense net model) and in the second one the material is homogeneous but anisotropic (as proposed by Gassel, Ogden, Holzapfel). Parameters of both models...
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Design aspects of a low-cost prosthetic arm for people with severe movement disabilities
PublicationIn this paper the main aspects of mechanical design behind the low-cost prosthetic arm are presented. The fundamentals of a proper design has been defined to obtain functional 3D printed 5 degree of freedom (DOF) prosthesis. The designed prosthetic arm is a part of the hybrid interface with eye tracking movement control. The main focus was to create affordable but usable prosthesis which corresponds in size and weights to the human...
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WYKORZYSTANIE TESTU MUSHRA W BADANIU KORZYŚCI UŻYTKOWANIA PROTEZ SŁUCHOWYCH
PublicationOcena jakości dopasowania aparatów słuchowych w kontekście korzyści, jakie może przy-nieść proteza jest złożonym zagadnieniem. Obiektywne parametry aparatów, które można wy-znaczyć (np. wzmocnienie czy pasmo przenoszenia) nie zawsze mają bezpośredni i decydujący wpływ w subiektywnej ocenie jakości dopasowania protezy słuchowej przez pacjenta. Pomiary efektywności aparatu słuchowego mogą dotyczyć wielu aspektów, między innymi kompensacji...
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DEEP LEARNING BASED ON X-RAY IMAGING IMPROVES COXARTHROSIS DETECTION
PublicationObjective: The purpose of the study was to create an Artificial Neural Network (ANN) based on X-ray images of the pelvis, as an additional tool to automate and improve the diagnosis of coxarthrosis. The research is focused on joint space narrowing, which is a radiological symptom showing the thinning of the articular cartilage layer, which is translucent to X-rays. It is the first and the most important of the radiological signs...
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A study on signal processing methods applied to hearing aids
PublicationThis paper presents a short survey on current technology available in hearing aids with a focus on digital signal processing techniques used. First, factors influencing the hearing aid effectiveness are introduced. Then, examples of the present DSP methods and strategies are provided. Also, a description of current limitations of hearing aids and future trends of development are shown. Finally, the notion of computational auditory...
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Surgical Site Infection after Breast Surgery: A Retrospective Analysis of 5-Year Postoperative Data from a Single Center in Poland
PublicationBackground and Objectives: Surgical site infection (SSI) is a significant complication of non-reconstructive and reconstructive breast surgery. This study aimed to assess SSI after breast surgery over five years in a single center in Poland. The microorganisms responsible for SSI and their antibiotic susceptibilities were determined. Materials and Methods: Data from 2129 patients acquired over five years postoperatively by the...
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Properties of surface layers of titanium alloy Ti6Al4V after laser melting processes
PublicationThe article presents the investigation results of titanium alloy Ti6Al4V surface layer after laser melting process. The process of laser melting was performed using Nd-YAG laser. The evaluation of structure of the alloy as well as hardness and chemical composition was performed. It was shown that laser melting changes the structure and properties of titanium alloy Ti6Al4V and process parameters as scanning speed affects the thickness...
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Polyurethanes as a carrier of drugs for gentamicin
PublicationGentamicin is one of the most popular drug and is widely used due to its antibiotic properties. 3% of world production of polyurethanes (PU) is dedicated to biomedical applications, where they can serve are parts of orthopedic prosthesis or artificial organs, disposable medical devices, wound and burn dressing, contact lenses among others. In the study, to obtain drug carriers, a combination of these two materials were prepared...
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Combined numerical and experimental approach to determine numerical model of abdominal scaffold
PublicationA proper junction of the prosthesis and the abdominal wall is important in successful hernia repair. The number of tacks should be balanced to assure appropriate mesh fixation and not to induce post-operative pain. Numerical simulations help to find this balance. The study is aimed at creating a proper numerical model of a knitted surgical mesh subjected to boundary conditions and load occurring in the abdominal cavity. Continuous,...
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Biocompatibility and Bioactivity of Load-Bearing Metallic Implants
PublicationThe main objective of here presented research is to develop the titanium (Ti) alloy base composite materials possessing better biocompatibility, longer lifetime and bioactivity behaviour for load-bearing implants, e.g. hip joint and knee joint endoprosthesis. The development of such materials is performed through: modeling the material behaviour in biological environment in long time and developing of new procedures for such evaluation;...
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Bypass kolejowy dla wiaduktu łukowego i kratownicowego w ciągu modernizowanej linii kolejowej E59 na odcinku Wronki – Dobiegniew
PublicationW artykule przedstawiono realizacje bypassu kolejowego, zlokalizowanego nieopodal miejscowości Krzyż Wielkopolski w ciągu linii kolejowej E59 na skrzyżowaniu z linią kolejową 203. Wariantowa analiza kilku zaproponowanych rozwiązań wykazała, ze wykonstruowanie bypassu na czas prowadzenia prac modernizacyjnych pozwoli na utrzymanie ciągłości ruchu kolejowego, nie stworzy nadmiernych problemów podróżnym, a jednocześnie pozwoli na...
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Composites in energy storing prosthetic feet
PublicationComposites reinforced with carbon and glass fibers have become the commonly used material in the production of energy storing prosthetic feet (ESPF/elastic feet prostheses). Their properties ensure a stable and light structure that allows for accumulation, storage and release of energy during walking, thus ensuring an increase in gait efficiency. Depending on the modification of the composite in terms of fiber selection, their...
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Nietypowa podziemna konstrukcja oporowa w technologii DSM jako zabezpieczenie głębokiej wymiany gruntu
PublicationW artykule przedstawiono nietypowe rozwiązanie podparcia i zabezpieczenia głębokiej wymiany gruntu z zastosowaniem przestrzennej konstrukcji oporowej w technologii DSM, ze względu na ograniczenie miejsca oraz zapewnienie stateczności nasypu drogowego. Opisano również realizację rozwiązania oraz prowadzony monitoring geotechniczny.
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Nietypowa podziemna konstrukcja oporowa w technologii DSM jako zabezpieczenie głębokiej wymiany gruntu
PublicationW artykule przedstawiono nietypowe rozwiązanie podparcia i zabezpieczenia głębokiej wymiany gruntu z zastosowaniem przestrzennej konstrukcji oporowej w technologii DSM, ze względu na ograniczenie miejsca oraz zapewnienie stateczności nasypu drogowego. Opisano również realizację rozwiązania oraz prowadzony monitoring geotechniczny.
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Optimal placement of IMU sensor for the detection of children activity
PublicationIn this paper an investigation to determine the optimal placement of IMU sensors for the purpose of children characteristic activity detection is presented. The article compares four different placement of two IMU sensors on human body. Ten healthy volunteers participated within the study. Data were collected firstly from two wireless 9-axial IMU sensors placed at the left and right wrists, then sensors were placed at lower back...
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Approach for Determination of Functioning of Lower Limb Muscles
PublicationThe purpose of the study is elaboration of approach for determination of functioning of chosen muscles that are essential for gait performance (Tibialis Anterior, Rectus Femoris, Gastrocnemius Medialis, Biceps Femoris). The scope of the study involves the analysis of the symmetric planar motion performing in the sagittal plane of the body by applying planar multibody model and electromyography signals (EMG) registered over normal...
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Quantitative Analysis of Biofilm Formed on Vascular Prostheses by Staphylococcus Epidermidis with Different ica and aap Genetic Status
PublicationOBJECTIVES: This study aims to examine biofilm formed on vascular prostheses by Staphylococcus epidermidis with different ica and aap genetic status, and to evaluate the effect of antibiotic-modified prostheses on bacterial colonization. METHODS: Biofilm formation was determined using fluorescence microscopy imaging. Quantitative analysis was conducted using the biofilm coverage ratio (BCR) calculations. RESULTS: Our investigations...
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Influence of the Addition of Recycled Aggregates and Polymer Fibers on the Properties of Pervious Concrete
PublicationThe aim of the study was to check the possibility of reusing aggregate from recycled concrete waste and rubber granules from car tires as partial substitution of natural aggregate. The main objective was to investigate the effects of recycled waste aggregate modified with polymer fibers on the compressive and flexural strength, modulus of elasticity and permeability of pervious concrete. Fibers with a multifilament structure and...
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Reconfiguring Minimum Dominating Sets in Trees
PublicationWe provide tight bounds on the diameter of γ-graphs, which are reconfiguration graphs of the minimum dominating sets of a graph G. In particular, we prove that for any tree T of order n ≥ 3, the diameter of its γ-graph is at most n/2 in the single vertex replacement adjacency model, whereas in the slide adjacency model, it is at most 2(n − 1)/3. Our proof is constructive, leading to a simple linear-time algorithm for determining...
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Introduction to the RSC Advances themed collection on nano and microscale modifications of biomaterials
PublicationThe dramatically increasing development of novel biomaterials, their manufacturing techniques, and surface modications, as well as their application in in vivo tests and clinical trials, is evident. It is interesting to note in what a relatively short time the well-known long-term implants have become medical standard: titanium dental implants started in 1965, and total hip arthroplasty (not very successful) was rst attempted...
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Environmental impact and industrial development of biorenewable resources for polyurethanes
PublicationPolyurethanes are among the most developed types of polymers. They are produced from the three primary components, i.e., polyols, low-molecular-weight glycols used as chain extenders, and diisocyanates. Until recently, all these substrates have been obtained via petrochemical processes. A decrease in petroleum-based resources and new ecological trends in chemistry, chemical technology, and materials engineering have generated increasing...
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Design of battery charging system update for glider launcher
PublicationThis paper presents an innovative solution for increasing life of lead-acid batteries used in a glider launcher. The study is focused on upgrading a charging system instead of a costly full replacement of it. Based on literature review, the advanced three-stage charging profile was indicated. The new topology of the power converter was proposed and a simulation model was developed. A simulation study was performed which leads to...
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The influence of time of hearing aid use on auditory perception in various acoustic situations
PublicationThe assessment of sound perception in hearing aids, especially in the context of benefits that a prosthesis can bring, is a complex issue. The objective parameters of the hearing aids can easily be determined. These parameters, however, do not always have a direct and decisive influence on the subjective assessment of quality of the patient’s hearing while using a hearing aid. The paper presents the development of a method for...
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The cement-bone bond is weaker than cement-cement bond in cement-in-cement revision arthroplasty. A comparative biomechanical study
PublicationThis study compares the strength of the native bone-cement bond and the old-new cement bond under cyclic loading, using third generation cementing technique, rasping and contamination of the surface of the old cement with biological tissue. The possible advantages of additional drilling of the cement surface is also taken into account. Femoral heads from 21 patients who underwent a total hip arthroplasty performed for hip arthritis...
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Usage of concentrated spectrogram for analysis of acoustical signals
PublicationA novel precise method of signal analysis in the time-frequency domain is presented. A signal energy distribution is estimated by discard and displacement of energy parts of the classical spectrogram. A channelized instantaneous frequency and a local group delay are used in order to energy replacement. Additionally, newly introduced representations such as: a channelized instantaneous bandwidth and a local group duration are used...
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A novel method of time-frequency analysis: an essential spectrogram
PublicationA novel precise method of time-frequency analysis is presented. In the algorithm, a new energy distribution is estimated by simultaneously discard or displacement of the classical spec- trogram energy. A channelized instantaneous frequency and a local group delay are used in order to replacement in the same manner as formulated by Kodera et al. [1, 2]. Additionally, new representations: a channelized instantaneous bandwidth and...
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The study on application of biopolyols obtained by cellulose biomass liquefaction performed with crude glycerol for the synthesis of rigid polyurethane foams
PublicationIn this work rigid polyurethane foams (PUR) were obtained by replacement of 0–70 wt% of petrochemical polyol with bio-polyol obtained via cellulose liquefaction in presence of crude glycerol. The foams with different content of a bio-polyol were prepared by single step method for NCO/OH ratio equals 1.5. The prepared materials were analyzed in terms of their morphology, chemical structure, thermal stability and basic physical and...
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Ocena wzmocnienia podłoża metodą wymiany dynamicznej na podstawie próbnych obciążeń kolumn
PublicationAnaliza wykonanego wzmocnienia słabego podłoża gruntowego pod nasyp drogowy w technologii kolumn DR na przykładzie obwodnicy Brodnicy. Omówienie warunków geotechnicznych podłoża i zastosowanych rozwiązań. Analiza wsteczna na podstawie wyników próbnych obciążeń kolumn oraz pomiarów osiadań wzmocnionego podłoża całego obszaru. Porównanie uzyskanych wyników i wnioski.
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PAYMENT TRANSACTIONS’ ENERGY EFFICIENCY
PublicationThe payment system and infrastructure is a sector that is not given enough attention today in the context of energy efficiency. This sector plays a big role in organizing and ensuring money circulation and funds. It has its value consisting on the one hand of the cost of payment equipment, infrastructure, payment instruments. On other hand, its value consists of the cost of energy for their manufacture and maintenance. The European...
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Smooth Particle Hydrodynamics (SPH) approach in simulating large penetration into soil
PublicationA study of Smooth Particle Hydrodynamics (SPH) approach for predicting large soil deformation is presented. Theoretical basics of SPH method, including the equations governing, discussion of the importance of smoothing function length, contact formulation, boundary treatment and finally utilization in hydrocodes simulations are presented. An application of SPH to a real case of large penetrations (crater creating) into soil caused...
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The role of EMG module in hybrid interface of prosthetic arm
PublicationNearly 10% of all upper limb amputations concern the whole arm. It affects the mobility and reduces the productivity of such a person. These two factors can be restored by using prosthetics. However, the complexity of human arm makes restoring its basic functions quite difficult. When the osseointegration and/or targeted muscle reinnervation (TMR) are not possible, different modalities can be used to control the prosthesis. In...
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Structural Factors Affecting Cytotoxic Activity of (E)-1-(Benzo[d ][1,3]oxathiol-6-yl)-3-phenylprop-2-en-1-one Derivatives
PublicationDerivatives of (E)-1-(5-alkoxybenzo[d][1,3]oxathiol-6-yl)-3-phenylprop-2-en-1-one (1) demonstrated exceptionally high in vitro cytotoxic activity, with IC50 values of the most active derivatives in the nanomolar range. To identify structural fragments necessary for the activity, several analogs deprived of selected fragments were prepared, and their cytotoxic activity was tested. It was found that the activity depends on combined effects...
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The Analysis and Solutions to the Problems of IPv6 Configuration Migration of Small Networks
PublicationThe paper analyzes the problems of IPv4 to IPv6 migration processes and indicates the areas in which migration can be done without expensive replacement of hardware, software and organizational changes. This paper presents the migration tools developed for the SOHO network administrators. The tools provide theoretical knowledge and practical advices on migrating to IPv6 and enable automation of the migration process. The article...
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Prediction of the fatigue lifetime of PUR structural elements using a combined experimental-numerical approach
PublicationThis paper presents a method for estimating the fatigue life of polyurethane elastomeric components. A rubber replacement - polyurethane of hardness 80ShA commonly used in vibration damping systems, for example, in motor vehicle suspensions, was used for the study. A metal-rubber bushing component was selected for analysis, and numerical analysis was carried out along with a fatigue model proposal based on a modification of the...
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SERVICE ORIENTED SCENARIOS FOR SUPPORT ENTERPRISE PROJECT MANAGEMENT
PublicationIn the paper, a service oriented architecture is used to describe various scenarios of human-oriented enterprises. They can be modeled by BPMN to show basic information flow. We consider business scenarios to present another modeling solution called service orchestration or service mashup. That approach gives an opportunity for the right management through taking the best possible choice of services, or composition of services....
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Study of Nanohydroxyapatite Coatings Prepared by the Electrophoretic Deposition Method at Various Voltage and Time Parameters
PublicationThe aim of the work is to compare the properties of nanohydroxyapatite coatings obtained using the electrophoretic deposition method (EDP) at 10 V, 20 V, and 30 V, and with deposit times of 2 and 5 min. The primary sedimentation was used to minimize the risk of the formation of particle agglomerates on the sample surface. Evaluation of the coating was performed by using a Scanning Electron Microscope (SEM), Energy-Dispersive Spectroscopy...
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Uniform sampling in constrained domains for low-cost surrogate modeling of antenna input characteristics
PublicationIn this letter, a design of experiments technique that permits uniform sampling in constrained domains is proposed. The discussed method is applied to generate training data for construction of fast replacement models (surrogates) of antenna input characteristics. The modeling process is design-oriented with the surrogate domain spanned by a set of reference designs optimized with respect to the performance figures and/or operating...
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Analysis of the Application of Horizontal Directional Drilling
PublicationConstruction works are often considered to be very intrusive for the environment. Project designers assume deep excavations, or a complete replacement of the ground within the investment, which sometimes changes the initial conditions drastically. The problem started to appear in places, where the terrain is complicated and the excavation is burdensome. Some of state authorities...
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Why is IPv6 Deployment Important for the Internet Evolution?
PublicationAbstract-Replacing the IPv4 protocol with IPv6 on the Internet is currently one of the aims of the European Union policy. The main reason for this replacement is the effeteness of the addresses pool in the IPv4 protocol, which can cause serious complications in the evolution of the Internet and its adaptation in new areas, e.g., in next generation mobile telephony or the so called Internet of Things. Simultaneously, the addressing...
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Role of methylation in electron scattering on X(CH3)4 (X= C, Si, Ge) molecules (2)
PublicationTo investigate how replacement of H atom with methyl group (CH3) – in tetrahedral compounds of carbon, silicon and germanium – affects electron scattering process, total cross sections (TCS) for electron scattering from C(CH3)4, Si(CH3)4 and Ge(CH3)4 molecules have been compared with data for CH4, SiH4 and GeH4 molecules. All examined data have been obtained with the same experimental setup. The shape of all discussed TCS energy...
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Mining Knowledge of Respiratory Rate Quantification and Abnormal Pattern Prediction
PublicationThe described application of granular computing is motivated because cardiovascular disease (CVD) remains a major killer globally. There is increasing evidence that abnormal respiratory patterns might contribute to the development and progression of CVD. Consequently, a method that would support a physician in respiratory pattern evaluation should be developed. Group decision-making, tri-way reasoning, and rough set–based analysis...