21 research outputs found

    Effectiveness of stretching exercises in conservative therapy of plantar fasciitis (PF)

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    Introduction and objective: Plantar fasciitis affects both young active patients and older people leading a sedentary lifestyle. It is result from chronic overload of the plantar fascia. About 80% of patients with plantar fasciitis improve within 12 months with non-surgical treatment. Nonsurgical management includes e.g. activity modification, cooling, non-steroidal anti-inflammatory drugs, stretching and strengthening exercises and manual therapy.   Materials and methods: PubMed database was searched. The criteria for qualifying the articles for the review were the following keywords: plantar fasciitis, muscle stretching, exercise, manual therapy, heel spur. 11 articles from 2017 to 2022 were analyzed.   Description of the state of knowledge: Calf stretching is one of the treatments for plantar fasciitis with the best results in the long run. In turn, strengthening exercises turn out to be more effective in a short time. One should also not forget about influence other methods of conservative treatment, such as cooling, orthoses or physical therapy, that support and accelerate the treatment process.   Summary: Strengthening exercises of the plantar fascia are more effective than stretching in terms of reducing pain and improving function in the short term, while stretching exercises show better results in the long term. The best results are obtained by combining stretching of the triceps calf muscle with other methods of conservative treatment. There are no studies supporting the hypothesis that stretching alone is more effective in the treatment process than other methods and placebo

    Structure and some magnetic properties of (BiFeO3)x-(BaTiO3)1-x solid solutions prepared by solid-state sintering

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    This paper presents the results of the study on structure and magnetic properties of the perovskite-type (BiFeO3)x-(BaTiO3)1-x solid solutions. The samples differing in the chemical composition (x = 0.9, 0.8, and 0.7) were produced according to the conventional solid-state sintering method from the mixture of powders. Moreover, three different variants of the fabrication process differing in the temperatures and soaking time were applied. The results of X-ray diffraction (XRD), Mössbauer spectroscopy (MS), and vibrating sample magnetometry (VSM) were collected and compared for the set of the investigated materials. The structural transformation from rhombohedral to cubic symmetry was observed for the samples with x = 0.7. With increasing of BaTiO3 concentration Mössbauer spectra become broadened reflecting various configurations of atoms around 57Fe probes. Moreover, gradual decreasing of the average hyperfine magnetic field and macroscopic magnetization were observed with x decreasing

    ANALIZA NIEZAWODNOŚCI SYSTEMU ZABEZPIECZENIA REAKTORA TYPU PWR

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    The aim of this work was to assess the probability of the Westinghouse PWR reactor protection system (RPS) unavailability. The reference facility for which the analysis has been made was Surry Nuclear Power Plant located in the United States. This work includes RPS fault tree development and qualitative analysis using the SAPHIRE code, as well as the uncertainty assessment by applying the Monte Carlo techniques.Celem niniejszej pracy było określenie prawdopodobieństwa niedostępności systemu zabezpieczenia reaktora typu PWR firmy Westinghouse. Obiektem referencyjnym, dla którego wykonano analizę była Elektrownia Jądrowa Surry zlokalizowana w Stanach Zjednoczonych. Praca ta obejmuje utworzenie drzewa uszkodzeń i wykonanie analizy ilościowej w programie SAPHIRE oraz oszacowanie niepewności za pomocą metod Monte Carlo

    ANALIZA NIEZAWODNOŚCI AWARYJNEGO ODBIORU CIEPŁA POWYŁĄCZENIOWEGO W REAKTORZE TYPU PWR

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    The aim of this work was to assess the failure probability of the Westinghouse PWR auxiliary feedwater system (AFWS). The reference facility for which the analysis has been made was Surry Nuclear Power Plant located in the United States. This work includes AFWS fault tree development and qualitative analysis using the SAPHIRE code, as well as the uncertainty assessment by applying the Monte Carlo techniques.Celem niniejszej pracy było określenie prawdopodobieństwa awarii pomocniczego systemu wody zasilającej reaktora typu PWR firmy Westinghouse. Obiektem referencyjnym, dla którego wykonano analizę była Elektrownia Jądrowa Surry (USA). Praca ta obejmuje utworzenie drzewa uszkodzeń i wykonanie analizy ilościowej w programie SAPHIRE oraz oszacowanie niepewności za pomocą metod Monte Carlo

    ZINTEGROWANY PROCES DECYZYJNY UWZGLĘDNIAJĄCY RYZYKO W PRZEMYŚLE JĄDROWYM

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    The regulatory body, established to ensure safety of nuclear facilities, is expected to make right decisions and provide appropriate regulations for the nuclear industry. The traditional manner of its activity has been based on a deterministic approach to safety analyses. However, increased maturity of Probabilistic Safety Assessment (PSA) makes it complementary to deterministic studies. The new IAEA concept, described in this article, is to apply an integrated approach by combining both deterministic and probabilistic insights with other requirements affecting the decision making process.Organ regulacyjny, powołany w celu zapewnienia bezpieczeństwa jądrowego, jest odpowiedzialny za podejmowanie decyzji i wprowadzanie rozporządzeń dla przemysłu jądrowego. Tradycyjny sposób jego funkcjonowania opiera się na deterministycznym podejściu do analiz bezpieczeństwa. Rozwój analiz probabilistycznych (PSA) sprawia jednak, iż są one traktowane jako podejście komplementarne. Nowa koncepcja IAEA, opisana w tym artykule, polega na zintegrowanym podejściu, uwzględniającym analizy deterministyczne, probabilistyczne i inne aspekty procesu decyzyjnego

    ZASTOSOWANIE IRIDM W PROCESIE DECYZYJNYM DOTYCZĄCYM KONWERSJI PALIWA W REAKTORZE MARIA

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    Poland, when acceded to GTRI (Global Threat Reduction Initiative) in 2004, has committed to convert the nuclear fuel of the Research Reactor MARIA, operated by the National Centre for Nuclear Research (NCBJ) in Świerk. The conversion means giving up of high enriched uranium fuel containing 36% of U-235, which was used so far, and replacing it with the low enriched uranium fuel (19.7% U-235). This article describes the potential usability of the Integrated Risk Informed Decision Making (IRIDM) methodology in optimization of the fuel conversion procedure.Polska, przystępując w 2004 roku do programu GTRI (Inicjatywa Redukcji Zagrożeń Globalnych), zobowiązała się do konwersji paliwa jądrowego w reaktorze badawczym MARIA, eksploatowanym przez Narodowe Centrum Badań Jądrowych (NCBJ) w Świerku. Konwersja ta oznacza rezygnację z dotychczas użytkowanego paliwa, zawierającego 36% U-235 i zastąpienie go paliwem nisko wzbogaconym (19.7% U-235). Niniejszy artykuł opisuje potencjalne zastosowanie zintegrowanego procesu decyzyjnego (IRIDM) w optymalizacji procedury konwersji paliwa

    Magnetoelectric effect in (BiFeO3)x-(BaTiO3)1-x solid solutions

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    The aim of the present work was to study magnetoelectric effect (ME) in (BiFeO3)x-(BaTiO3)1-x solid solutions in terms of technological conditions applied in the samples fabrication process. The rapidly growing interest in these materials is caused by their multiferroic behaviour, i.e. coexistence of both electric and magnetic ordering. It creates possibility for many innovative applications, e.g. in steering the magnetic memory by electric field and vice versa. The investigated samples of various chemical compositions (i.e. x = 0.7, 0.8 and 0.9) were prepared by the solid-state sintering method under three sets of technological conditions differing in the applied temperature and soaking time. Measurements of the magnetoelectric voltage coefficient αME were performed using a dynamic lock-in technique. The highest value of αME was observed for 0.7BiFeO3-0.3BaTiO3 solid solution sintered at the highest temperature (T = 1153 K) after initial electrical poling despite that the soaking time was reduced 10 times in this case

    ZALEŻNOŚĆ CZĘSTOTLIWOŚCIOWA NAPIĘCIOWEGO WSPÓŁCZYNNIKA MAGNETOELEKTRYCZNEGO W CERAMIKACH (BiFeO3)x-(BaTiO3)1-x

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    Composition-dependent magnetoelectric properties of sintered (BiFeO3)x-(BaTiO3)1-x ceramics have been recently observed and reported in the literature. Measurements of the magnetoelectric effect (ME) for these materials have been performed by usage of the dynamic method. The samples with x = 0.9, 0.8 and 0.7 were placed in a static (DC) magnetic field created by an electromagnet on which a sinusoidal (AC) magnetic field with a frequency of 1 kHz produced by Helmholtz coils was superimposed. In this work the theory of the dynamic measurement was presented and the optimal frequency of the AC field was determined in order to minimize the processes causing undesired reduction of the measured voltage signal.Zależność właściwości magnetoelektrycznych od składu chemicznego w ceramikach (BiFeO3)x-(BaTiO3)1-x została w ostatnim czasie zaobserwowana i odnotowana w literaturze. Pomiary efektu magnetoelektrycznego (ME) w tych materiałach wykonywane były metodą dynamiczną. Próbki o x = 0,9, 0,8 i 0,7 umieszczano w stałym (DC) polu magnetycznym generowanym przez elektromagnes, na które nałożono zmienne (AC) pole magnetyczne o częstotliwości f = 1kHz wytwarzane przez cewki Helmholtza. W niniejszej pracy przedstawiono podstawy teoretyczne tego rodzaju pomiarów oraz wyznaczono optymalną częstotliwość pola AC, która minimalizuje procesy powodujące redukcję mierzonego sygnału napięciowego

    Magnetoelectric Effect in Ceramics Based on Bismuth Ferrite

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    Solid-state sintering method was used to prepare ceramic materials based on bismuth ferrite, i.e., (BiFeO3)1 − x–(BaTiO3)x and Bi1 − xNdxFeO3 solid solutions and the Aurivillius Bi5Ti3FeO15 compound. The structure of the materials was examined using X-ray diffraction, and the Rietveld method was applied to phase analysis and structure refinement. Magnetoelectric coupling was registered in all the materials using dynamic lock-in technique. The highest value of magnetoelectric coupling coefficient αME was obtained for the Bi5Ti3FeO15 compound (αME ~ 10 mVcm−1 Oe−1). In the case of (BiFeO3)1 − x–(BaTiO3)x and Bi1 − xNdxFeO3 solid solutions, the maximum αME is of the order of 1 and 2.7 mVcm−1 Oe−1, respectively. The magnitude of magnetoelectric coupling is accompanied with structural transformation in the studied solid solutions. The relatively high magnetoelectric effect in the Aurivillius Bi5Ti3FeO15 compound is surprising, especially since the material is paramagnetic at room temperature. When the materials were subjected to a preliminary electrical poling, the magnitude of the magnetoelectric coupling increased 2–3 times

    X-ray diffraction, Mossbauer spectroscopy, and magnetoelectric effect studies of (BiFeO3)x-(BaTiO3)1-x solid solutions

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    In this work the hyperfine interactions in (BiFeO3)x-(BaTiO3)1–x solid solutions with relation to their structural properties have been investigated. X-ray diffraction, Mössbauer spectroscopy and magnetoelectric effect measurements have been used for studies of sintered (BiFeO3)x-(BaTiO3)1–x solid solutions with x = 0.9, 0.8 and 0.7. With increasing contents of BaTiO3, the structural transformation from rhombohedral to cubic was observed. The weakening of the hyperfine magnetic fields accompanied by this transformation. On the other hand, the increasing amount of BaTiO3 caused an increase of the magnetoelectric effect
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