APPLICATION OF AN MEMETIC ALGORITHM TO PLACEMENT OF SENSORS FOR ACTIVE NOISE-VIBRATION CONTROL

For successful active control of a vibrating structure it is essential to appropriately place sensors. One of the most important criteria is to make the system observable, so any control objectives can be achieved. In this paper the observability-oriented placement of sensors is undertaken. First, a theoretical model of a fully clamped plate is presented. Optimization criterion based on maximization of observability of the system is developed. A memetic algorithm is used to find the optimal solution. Obtained results are compared with those obtained by the genetic algorithm. The configuration is also validated experimentally

Application of an memetic algorithm to placement of sensors for active noise-vibration control Zastosowanie algorytmu memetycznego do rozmieszczenia czujników w celu aktywnej redukcji drgań i hałasu /

Tyt. z nagłówka.Bibliogr. s. 127-[128].For successful active control of a vibrating structure it is essential to appropriately place sensors. One of the most important criteria is to make the system observable, so any control objectives can be achieved. In this paper the observability-oriented placement of sensors is undertaken. First, a theoretical model of a fully clamped plate is presented. Optimization criterion based on maximization of observability of the system is developed. A memetic algorithm is used to find the optimal solution. Obtained results are compared with those obtained by the genetic algorithm.The configuration is also validated experimentally.W celu skutecznej aktywnej redukcji drgań i hałasu konstrukcji konieczne jest odpowiednie rozmieszczenie czujników. Jednym z najważniejszych kryteriów jest uczynienie obiektu obserwowalnym, aby jakiekolwiek cele sterowania mogły zostać osiągnięte.W pracy podjęte zostało zagadnienie rozmieszczenia czujników w oparciu o analizę obserwowalności. Zaprezentowany został model teoretyczny płyty o brzegach całkowicie utwierdzonych. Wyprowadzone zostało kryterium optymalizacji w oparciu o maksymalizacje miary obserwowalności. Do znalezienia rozwiązania optymalnego zastosowano algorytm memetyczny. Otrzymane wyniki zostały porównane z wynikami uzyskanymi za pomocą algorytmu genetycznego. Wyznaczone rozmieszczenie czujników zostało zweryfikowane eksperymentalnie.Dostępny również w formie drukowanej.SŁOWA KLUCZOWE: aktywna redukcja drgań i hałasu, elastyczne struktury, rozmieszczenie czujników, macierz Grama obserwowalności, algorytm genetyczny, algorytm memetyczny. KEYWORDS: active control, flexible structures, sensor placement, observability Gramian, genetic algorithm, memetic algorithm

Bentonite granulates as a seals for mobile flood barriers

Bentonity i inne surowce smektytowe są szeroko stosowane w wielu gałęziach przemysłu. Autorzy niniejszej pracy dokonali analizy przydatności bentonitowych granulatów pęczniejących w celu ich użycia jako uszczelnień w mobilnych zaporach przeciwpowodziowych. Do tego celu dokonano analizy porównawczej parametrów pęcznienia i uziarnienia trzech dostępnych na rynku granulatów a następnie wykonano próbę makroskopową pęcznienia na specjalnie do tego celu przygotowanym stanowisku badawczym. Wykonane badania wykazały, że nie tylko udział składnika pęczniejącego – smektytu – znacząco wpływa na doszczelnianie układu, ale determinuje go przede wszystkim rozkład wielkości granul i rodzaj smektytu.Bentonites and other smectite raw materials are widely used in many industries. The authors of the study analyzed the suitability of swelling granulates for their use as a seals in mobile flood barriers. For this purpose, a comparative analysis of the swelling and granulation parameters of three samples available on the market was performed. This results was compared with a macroscopic swelling test, which was realized on the specially prepared test stand. The carried out research shows that not only the content of the swelling minerals – mainly smectite – affect on the sealing of the system, but also they are determine by granules size distribution and the type of smectite

Dynamic Knowledge Management in an Agent-Based Extended Green Cloud Simulator

Cloud infrastructures operate in highly dynamic environments, and today, energy-focused optimization become crucial. Moreover, the concept of extended cloud infrastructure, which, among others, uses green energy, started to gain traction. This introduces a new level of dynamicity to the ecosystem, as “processing components” may “disappear” and “come back”, specifically in scenarios where the lack/return of green energy leads to shutting down/booting back servers at a given location. Considered use cases may involve introducing new types of resources (e.g., adding containers with server racks with “next-generation processors”). All such situations require the dynamic adaptation of “system knowledge”, i.e., runtime system adaptation. In this context, an agent-based digital twin of the extended green cloud infrastructure is proposed. Here, knowledge management is facilitated with an explainable Rule-Based Expert System, combined with Expression Languages. The tests were run using Extended Green Cloud Simulator, which allows the modelling of cloud infrastructures powered (partially) by renewable energy sources. Specifically, the work describes scenarios in which: (1) a new hardware resource is introduced in the system; (2) the system component changes its resource; and (3) system user changes energy-related preferences. The case study demonstrates how rules can facilitate control of energy efficiency with an example of an adaptable compromise between pricing and energy consumption

Influence of Double-Panel Structure Modification on Vibroacoustical Properties of a Rigid Device Casing

Nowadays, noise generated by devices is a serious issue in industry and in everyday life, because it may cause health damage to humans. In this research, a cubic rigid device casing built of double-panel thin steel walls is employed to reduce noise emitted from an enclosed noise source. Double-panel structure is used because of good sound insulation it provides. There exist three main groups of noise reduction methods, i.e. passive, semi-active and active. In this paper, a semi-active modification of double-panel structure is applied and examined. The bistable actuator (solenoid) mounted between incident and radiating plates changes its state due to applied constant voltage, causing the coupling of plates. Experimentally measured natural frequencies and modeshapes of the structure are compared to the simulation results. The influence of proposed modification on dynamical properties of the structure is analyzed and discussed

The Lack of Association between the Polymorphism of Codon 650 in gamma Subunit of Epithelial Sodium Channel and Sodium-sensitivity of Blood Pressure

Wstęp: W patogenezie nadciśnienia tętniczego odgrywają rolę zarówno czynniki środowiskowe, jak i genetyczne. Nadmierna reabsorpcja sodu w dalszym kanaliku nerkowym, wywołana konstytutywną aktywacją nabłonkowego kanału sodowego (NKS), prowadzi do rozwoju sodowrażliwego nadciśnienia tętniczego w zespole Liddle'a. Konstytutywna aktywacja NKS jest wynikiem mutacji genów podjednostek beta i gamma tego kanału. W 1998 roku odkryto polimorfizm ostatniego, 650 kodonu (CTC) genu podjednostki gammaNKS. Polimorfizm gamma650 dotyczył występowania transwersji C na G w trzeciej pozycji kodonu. Dlatego też cele naszej pracy obejmowały: opracowanie metody wykrywania tej transwersji oraz próbę oceny związku polimorfizmu gamma650 NKS z cechą sodowrażliwości ciśnienia tętniczego. Metody: Badania przeprowadzono u 76 dorosłych, szczupłych (BMI < 25 kg/m2) chorych rasy kaukaskiej z samoistnym nadciśnieniem tętniczym klasy I wg WHO. Chorzy zostali podzieleni na dwie grupy: 50 chorych na nadciśnienie tętnicze sodowrażliwe (SS) i 26 chorych na nadciśnienie tętnicze sodoniewrażliwe (SR). Genomowy DNA z leukocytów krwi obwodowej amplifikowano w łańcuchowej reakcji polimerazowej (PCR) z primerami flankującymi obszar polimorficzny kodonu gamma 650. Obecność transwersji C na G identyfikowano na podstawie utraty miejsca restrykcyjnego Sac I. Wyniki: Nie stwierdzono istotnych różnic pomiędzy badanymi grupami w częstości występowania zarówno poszczególnych genotypów, jak i apeli kodonu gamma650 (odpowiednio genotypy: 60,0% CC, 38,0% CG i 2,0% GG w grupie SS, a 53,8% CC, 42,3% CG i 3,8% GG w grupie SR oraz allele: 79,0% C+ 21,0% G w grupie SS i 75,0% C + 25,0% G w grupie SR). W porównaniu z grupą SR, u chorych na nadciśnienie sodowrażliwe stwierdzono istotnie wyższe wartości filtracji kłębkowej (GFR) oraz istotnie niższą wydalaną frakcję filtrowanego sodu (FENa). Dodatkowo w obrębie grupy SS u chorych z apelem G odnotowano istotnie niższe wartości GFR w porównaniu z chorymi z genotypem typu dzikiego (CC). Wnioski: Wstępne wyniki naszej pracy sugerują duże rozpowszechnienie polimorfizmu kodonu gamma650 genu podjednostki gammma nabłonkowego kanału sodowego w populacji chorych z samoistnym nadciśnieniem tętniczym oraz brak związku tego polimorfizmu z cechą sodowrażliwości ciśnienia tętniczego.Background Both enviromental and genetic factors have been implicated in the pathogenesis of essential hypertension. The excessive sodium reabsorption due to the constitutive activation of the renal epithelial channel (ESC) leads to the development of sodiusensitive hypertension in Liddle's syndrome. The constitutive activation of ESC is caused by the truncating or missense mutations of genes for ß or gamma ESC subunits. The common polymorphism in the codon 650 of gamma ESC has been identified last year. The gamma 650 ESC polymorphism concerns the C to G transversion of the third nucleotide in the last 650 codon. Therefore, the aims of our study were to establish the method for detection of gamma 650 ESC polymorphism and subsequently to evaluate the association between gamma650 ESC polymorphism and the sodium-sensitivity of blood pressure. Methods The study was carried out in 76 adult, lean (BMI < 25 kg/m2) Caucasian patients with essential hypertension (WHO I stage). The patients were divided into two groups: 50 subjects with sodiu-sensitive hypertension (SS) and 26 subjects with sodium-nonsensitive hypertension (SR). Genomic DNA isolated from peripheral blood nuclear cells was amplified by PCR method with primers flanking the polymorphic region. The gamma650ESC polymorphism was identified by loss of Sac I restriction site. Results No significant differences in genotype frequency as well as allele frequency have been found between both groups (genotypes: 60.0% CC, 38.0% and 2.0% GG in SS versus 53.8% CC, 42.3% CG and 3.8% GG in SR, and alleles: 79.0% C+ 21.0% G in SS versus 75.0% C + 25.0% G in SR, respectively). The significantly higher glomerular filtration rate (GFR) and significantly lower excreted fraction of filtered sodium (FENa) have been observed in SS patients as compared with SR group. In addition, within the SS group the significantly lower GFR has been found in patients with G allele as compared with patients with wild type genotype (CC homozygotes). Conclusions Our preliminary results suggest the high prevalence of gamma650 ESC polymorphism in Caucasians with essential hypertension and the lack of association between the gamma650ESC polymorphism and sodium-sensitivity of blood pressure

Ni–Cr Powders Modified with Rhenium as a Novel Coating Material—Physical Properties, Microstructure, and Behavior in Plasma Plume

The aim of this work was to develop a new coating material based on Ni20Cr alloy modified with up to 50%wt. rhenium. The modification was carried out by the mechanical mixing of the base powder and ammonium perrhenate with the subsequent thermoreduction in an H2 atmosphere. The obtained powder consists of a nickel–chromium core surrounded by a rhenium shell. The characterization of the powders—including their microstructure, phase and chemical composition, density, flowability, particle size distribution, and specific surface area—was performed. The influence of plasma current intensity and hydrogen gas flow on in-flight particle temperature and velocity were investigated. The results indicate that there is interdiffusion between the base Ni20Cr and the rhenium shell, resulting in intermediary solid solution(s). The modified powders have a higher specific surface area and a lower flowability, but this does not prevent them from being used as feedstock in plasma spraying. In-flight measurements reveal that increasing the content of rhenium allows for the higher temperature of particles, though it also reduces their speed

Pulmonary Embolism Response Team — a multidisciplinary approach to pulmonary embolism treatment. Polish PERT Initiative Report

Background: A pulmonary embolism response team (PERT) is a multidisciplinary team established to improve clinical care for patients with pulmonary embolism (PE). However, data regarding detailed institutional experience and clinical outcomes from such teams are sparse.Aims: We aim to assess the frequency of activations, patients’ characteristics, PE severity, applied treatments, and outcomes of PE patients treated by Polish PERTs.Methods: The survey registry was conducted between June 2018 and July 2020. All consecutive PERT activations of four institutionalized PERTs in Poland were analyzed. Patients’ characteristics, therapies applied, and in-hospital outcomes were evaluated.Results: There were 680 unique PERT activations. The majority of activations originated from emergency departments (44.9%), and the remaining originated from internal medicine/cardiology units (31.1%), surgery/orthopedics (9.1 %), oncology (6.3%), intensive care units (6.0%), and others (2.5%). The origin of activation varied significantly between institutions (P &lt;0.01). Most PERT cases were patients with intermediate-high risk PE (42.9%), whereas high-risk PE occurred in 10% of patients. Anticoagulation alone was delivered to 80.3% patients, and 23.3% patients received at least one advanced therapy: catheter directed therapies (11.3%), systemic thrombolysis (5.3%), surgical embolectomy (2.4%), vena cava filter placement (3.7%), and extracorporeal membrane oxygenation (0.6%). In-hospital mortality in the whole study group was 5.1%, with significant differences between institutions (P = 0.01).Conclusions: The frequency of PE severity, type of delivered catheter-directed treatment, and in-hospital mortality varies between institutions without significant discrepancies in PERT activations. This variation between expert centers highlights the local differences in PERTs’ organizational and operational forms