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penalty factors, and data weights on the basis of the original fuzzy C-means clustering algorithm, thereby improving the generalization ability of the algorithm model and the credibility of the results. The optimized fuzzy C-means clustering algorithm had the highest level of accuracy value, with a value of 95.67%, which was 11.79% higher than the average accuracy of other algorithms. Meanwhile the optimized Fuzzy C-Means clustering algorithm improved the accuracy values of KNN, BP, SVM, and fuzzy C-means clustering algorithms by 19.65%, 12.26%, 3.55%, and 11.70%. The training set accuracy of the optimized fuzzy C-means clustering algorithm under four engine states was at the highest level, with an average improvement of 15.5%, 25%, 24%, and 16% in accuracy. The optimized fuzzy C-means clustering algorithm achieved an accuracy of 90.39% in the test set, with an average improvement of 16.13% in accuracy. The membership classification results indicated that the optimized fuzzy C-means clustering algorithm had a membership degree of 1.
została opracowana w silniku Unity.
Unity engine.
nawet dla interfejsów Wi-Fi 802.11 pracujących w paśmie mmWave z bardzo szerokimi kanałami częstotliwościowymi jest to możliwe. Wzorce zostały zaczerpnięte z rozwiązań stosowanych w dobrze rozpoznawalnym interfejsie CPRI (Common Public Radio Interface).
this is possible even for Wi-Fi 802.11 interfaces operating in the mmWave band with very wide frequency channels. The patterns were taken from solutions used in the well-recognized CPRI (Common Public Radio Interface).
CEN/TR 16639. W obecnej sytuacji prawnej użycie cementu CEM II/C m.in. do betonów klasy ekspozycji XC4 jest możliwe w świetle normy PN-B-06265:2022-08 jedynie po potwierdzeniu przydatności w drodze analizy równoważnych właściwości użytkowych wynikających z charakteru warunków eksploatacyjnych. Istota weryfikacji za pomocą równoważnych właściwości użytkowych betonu polega na porównaniu właściwości betonu referencyjnego rekomendowanego do zastosowania w danej klasie ekspozycji z właściwościami betonu testowego, zawierającego oceniany cement. Jako referencyjne przyjęto betony wykonane na cemencie CEMII/B-V 32,5R spełniające minimalne kryteria składu w przypadku klas ekspozycji XC2 lub XC4, a analizowane były betony wykonane na cemencie CEM II/C-M (W-LL) 32,5R.
the assessment of equivalent properties of both concretes. In the current legal situation, the use of CEM II/C cement, among others, for concrete of exposure class XC4, is possible of the PN-B-06265:2022-08 standard only after confirming its suitability by analyzing equivalent performance properties resulting from nature of the operating conditions. The essence of verification using equivalent performance properties of concrete is based on the comparison of the properties of reference concrete based on the solution recommended for use in a given exposure class to the properties of test concrete based on a new cement solution in terms of the assumed characteristics appropriate for the designed applications. The project included reference concretes made using CEM II/B-V 32.5R cement meeting the minimum composition criteria for exposure classes XC2 or XC4, and the tested concretes were concretes made using CEM II/C-M (W-LL) 32.5R cement.
technique that is compatible with long-distance communication systems. We demonstrate a long distance transmission of a 28 GHz 64 QAM signal via a single mode fiber (SMF) after modulating it with the use of two parallel Mach-Zehnder modulators, without any optical amplifiers. The results show that our prototype solution is capable of transferring data over distances of up to 140 km, via SMF, with a 10 Gbps data rate. The error vector magnitude (EVM) was found to be 7.709%. The proposed system offers exceptional capabilities in terms of supporting high bitrates, while ensuring that EVM remains within the 3GPP limits. Compared to other works, the proposed solution proves to be superior in terms of performance, making it an ideal choice for next generation long-haul communication systems.
response (FIR) of single-input single-output nonlinear systems under the influence of perturbations and binary-valued measurements. To overcome this challenge, we exploit two algorithms that leverage the framework of reproducing kernel Hilbert spaces (RKHS) to accurately identify the impulse response of the Proakis C channel. Additionally, we introduce the application of these kernel methods for estimating binary output data of nonlinear systems. We showcase the effectiveness of kernel adaptive filters in identifying nonlinear systems with binary output measurements, as demonstrated through the experimental results presented in this study.
pracy zbadano temperaturę przekroju w odległości a = 2, 4, 6, 8 cm od lica ogrzewanej powierzchni przekroju oraz określono położenie izotermy 500°C w sytuacji ogniowej R30-R240. Dodatkowo opracowano nomogramy, które mogą być pomocne do projektowania słupów lub belek żelbetowych w warunkach ogniowych z wykorzystaniem metody izotermy 500°C.
curve over a period from 0 to 240 minutes. The study investigated the temperature of the cross-section at distances of a = 2, 4, 6, 8 cm from the heated Surface of the cross-section and determined the location of the 500°C isotherm in fire scenarios R30-R240. Additionally, nomograms were developed that may be useful for designing reinforced concrete columns or beams under fire conditions using the 500°C isotherm method.
of the information and control (I&C) systems with two-cascade redundancy considering design faults manifestation during operation. The methodology of the research is based on Markov and semi-Markov chains with the utilization of multi-phase modeling. Several multi-phase models are developed and investigated considering different conditions of operation and failures caused by version faults. The case study of the research is based on the analysis of safety-critical nuclear power plant I&C systems such as the reactor trip systems developed using the programmable platform RadICS.
in the host rock of volcanic igneous rock, namely andesite. This study aims to determine the opal mineraloid host-rock’s microstructural characteristics and the elemental and compound content of the opal mineraloid host-rock’s geochemistry in the Rongkong area, Indonesia. The research took three samples in the field as large as hand specimens. The three samples were one host-rock sample and two opal mineraloid samples; the samples were then prepared and analyzed in the laboratory. Laboratory analysis was performed using SEM-EDS, XRF and petrographic analyses. The results of the SEM-EDS test analysis showed that most opal mineraloid carrier rock constituents are aluminum and oxide. This can be seen from the substantial Al and O content. In samples 1 and 2, Al, O, Ca and P with the highest composition of chemical compounds are Al2O3, CaO, and P2O5. The Rongkong opal mineraloid from Limbong Village, Rongkong District, North Luwu Regency, South Sulawesi, based on the results of XRF analysis, contains the chemical compounds SiO2, Al2O3, K2O, Fe2O3, CaO, TiO2, RuO2, SrO, MnO, V2O5, Rb2O, Ag2O and CuO. The content compound that is more dominant in opal mineraloids is SiO2 due to silicate enrichment in the forming of opal mineraloids.
Rongkong opal znajduje się w skale macierzystej wulkanicznej skały magmowej, a mianowicie w andezycie. Niniejsze badanie ma na celu określenie charakterystyki mikrostrukturalnej skały macierzystej opalu oraz zawartości pierwiastków i związków w geochemii skały macierzystej opalu w obszarze Rongkong w Indonezji. W ramach badań pobrano w terenie trzy próbki wielkości próbek ręcznych. Trzy próbki stanowiły jedną próbkę skały macierzystej i dwie próbki mineraloidu opalu; próbki zostały następnie przygotowane i przeanalizowane w laboratorium. Analiza laboratoryjna została przeprowadzona przy użyciu SEM-EDS, XRF i analiz petrograficznych. Wyniki analizy testowej SEM-EDS wykazały, że większość składników skały nośnej opalu to aluminium i tlenek. Widać to po znacznej zawartości Al i O. W próbkach 1 i 2 Al, O, Ca i P o najwyższym składzie związków chemicznych to Al2O3, CaO i P2O5. Minerał opalowy Rongkong z Limbong Village, Rongkong District, North Luwu Regency, South Sulawesi, w oparciu o wyniki analizy XRF, zawiera związki chemiczne SiO2, Al2O3, K2O, Fe2O3, CaO, TiO2, RuO2, SrO, MnO, V2O5, Rb2O, Ag2O i CuO. Składnikiem, który jest bardziej dominujący w mineraloidach opalowych, jest SiO2 ze względu na wzbogacenie krzemianów w tworzeniu mineraloidów opalowych.
then finally assembled into a completed airplane. Many parts of the completed airplane must be arranged so that they can be disassembled for shipping, inspection, repair or replacement and are usually joined by bolts or rivets. In order to facilitate the assembly and disassembly of the airplane, it is desirable for such bolted or riveted connections to contain as few fasteners as possible (which is guaranteed by composite structures). Nevertheless, the impact of birds or elements during the take-off or landing (the operation) of an aircraft sometimes generates a critical dispersion of impact energy in the composite structure due to the high heterogeneity (of resin or microbubbles) of the structure. For example, a metal wing usually resists bending stresses in numerous stringers and sheet elements distributed around the periphery of the wing cross sections. The wing cannot be made as one continuous riveted assembly. The new approach to design an inspection scope and schedule based on maintenance checks brings elements of novelty. Although the maintenance schedule can be obtained through simulation, the simulation results might not be accurate enough. The obtained results provide usable analytical solutions. However, without an additional wide data-collection program, the results can serve only advisory purpose for practicians.
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że na poziom wytrzymałości wczesnej większy wpływ ma stopień rozdrobnienia klinkieru portlandzkiego niż granulowanego żużla wielkopiecowego. Natomiast przemiał granulowanego żużla wielkopiecowego pozwala uzyskać znaczący przyrost wytrzymałości w późniejszym okresie dojrzewania, od 14 dnia. Najbardziej efektywnym rozwiązaniem jest połączenie efektu synergicznego uzyskanego z aktywacji mechanicznej [przemiału] granulowanego żużla wielkopiecowego i obniżonego współczynnika w/c z 0,5 do 0,3. Działanie takie znacznie zwiększa zakres stosowania niskoemisyjnych cementów żużlowych w budownictwie.
that the level of early strength is more influenced by the degree of grinding of Portland clinker than by granulated blast furnace slag. On the other hand, grinding of granulated blast furnace slag allows for significant increases in strength in the later maturation period, from the 14th day of maturation. The most effective solution is to combine the synergistic effect obtained from mechanical activation [grinding] of granulated blast furnace slag and a reduced w/c ratio from 0.5 to 0.3. Such action significantly increases the scope of application of low-emission slag cements in construction.
wytrzymałość na ściskanie zaczynów cementowych zawierających 0%, 5%, 10%, 15% i 20% masowych popiołu lotnego zastępującego cement portlandzki. Proces hydratacji, twardnienie i mikrostrukturę zaczynu cementowego analizowano z użyciem kalorymetrii, XRD, TG-DTG, SEM i MIP. Wyniki wykazały, że wraz ze wzrostem zawartości popiołu lotnego rozpływ zaczynu się zwiększył, czas wiązania najpierw skrócił, a następnie wydłużył się, a dodatek popiołu ograniczył skurcz zaczynu na późniejszym etapie. Gdy zawartość popiołu wynosiła 10%, rozpływ zwiększył się o 9.6%, a czas początku i końca wiązania uległ skróceniu odpowiednio o 23,4% i 12,1%. Jednocześnie efekt zarodkowania FA zapewnia powierzchnię dla wytrącania Ca(OH)2 i fazy C-S-H, co dysperguje wytworzone produkty hydratacji, przyspieszając hydratację i generując więcej AFt, poprawiając wytrzymałość na ściskanie. Na późniejszym etapie hydratacji efekt mikrowypełniacza sprawił, że nieuwodnione cząstki popiołu przecinają duże pory w zaczynie cementowym na małe połączone ze sobą pory, co poprawia ogólną zwartość zaczynu. Powyższe wyniki jeszcze bardziej rozwijają wartość użytkową FA i skutecznie rozszerzają zastosowanie trójskładnikowego systemu cementowego w inżynierii szybkich napraw.
fraction] fly ash substituted for OPC cement were tested. The hydration process, hardening, and microstructure of the cement slurry were analyzed by hydration heat, XRD, TG-DTG, SEM, and MIP test techniques. The results showed that with increasing FA content, the flowability of cement slurry improved, the setting time was shortened first and then lengthened, and the doping of FA can inhibit the shrinkage of the volume of the cementitious system at the later stage. When the FA content was 10 %, the flowability increased by 9.6 %, and the initial and final setting times were shortened by 23.4 % and 12.1 %, respectively. Simultaneously, the nucleation effect of FA provides a precipitation surface for Ca(OH)2 and C-S-H, which spreads the generated hydration products, accelerating the early hydration reaction rate and generating more AFt, improved its compressive strength. At the later stage of hydration, the micro-filler effect of FA made the unhydrated particles cut the large pores in the cement pore space into small interconnected pores, which improves the overall compactness of the slurry. The above results further develop the utilization value of FA and effectively expand the application of the ternary cementitious system in rapid repair engineering.
layer were tested and analyzed. The surfacing test plate was processed into a pulling specimen, and the bonding strength between the surfacing layer and the 45 steel base metal was tested with a self-designed pulling test method. The fracture location of the pulling specimen and fracture characteristics were observed by a metallurgical microscope and a scanning electron microscope. The result shows that with the increase of the amount of high carbon chromium iron added to flux-cored welding wire, the content of C and Cr in the surfacing layer increases, and the NbC hard phase disperses. The microstructure of the steel matrix changes from mixed martensite + residual austenite to high carbon martensite + residual austenite, and then independent austenite appears. The hardness of the surfacing layer first increases and then decreases. The bonding strength between the surfacing alloy and the 45 steel base metal first decreases and then increases, and the fracture location is at the bottom of the surfacing layer or the fusion zone with mostly quasi-cleavage characteristics. When the additional amount of high carbon chromium iron reaches 13%, thee pulling specimen exhibits significant deformation with the highest bonding strength, and the fracture is close to the fusion line, where there are numerous tearing edges and shallow dimples.
Halpin–Tsai model to capture the small-scale heterogeneity, which can simultaneously consider the grading effects of the matrix and reinforcement phases along with the dispersion distribution through the plate thickness. To meet the C1 continuity requirements of the couple stress theory, a four-node rectangular element is adopted by using the Hermitian approach and in the way of a sub-parametric manner. The element has 20 degrees of freedom (DOF) at each node, which is reduced to 12 DOF in a bending mode without stretching deformation. FG-NC plates’ bending, free vibration, and buckling behaviour are investigated. Graphene oxide (GO), reduced graphene oxide (rGO), and silver-reduced graphene oxide (Ag-rGO) are considered for the dispersed phase. Size-dependent optimal values for the material and geometrical properties of the FG-NC plate model are presented, which minimize its mass with the frequency constraint. The effects of various parameters such as grading index, weight fraction, dispersion pattern, filler aspect/thickness ratio, and length scale parameter are examined, and benchmark examples are provided.
cutting power, and material removal rate. To do so, the study relies on three approaches: (i) Pareto statistical analysis, (ii) multiple linear regression modeling, and (iii) optimization using the genetic algorithm. To conduct the investigation, mathematical models are developed using response surface methodology based on the Taguchi 𝐿16 orthogonal array. The results indicate that feed rate, nose radius, and cutting edge angle significantly influence surface quality, while depth of cut, feed, and speed have a notable impact on other machinability parameters. The developed mathematical models have determination coefficients greater than or very close to 95%, making them very useful for the industry as they allow predicting response values based on the chosen cutting parameters. Finally, the optimization using the genetic algorithm proves to be promising and effective in determining the optimal cutting parameters to maximize productivity while improving surface quality.
[1]. Mówi się, że witamina C jest niezbędna do prawidłowego funkcjonowania organizmu. Przyspiesza ona proces gojenia się ran, aktywuje liczne enzymy, zapobiega powstawaniu zmarszczek, wyrównuje naturalny koloryt skóry, czy także wzmacnia zęby i dziąsła dodatkowo zwalczając bakterie powodujące próchnicę [2]. Czego możemy się spodziewać, gdy włączymy witaminę młodości do codziennej pielęgnacji? Jak wpływa ona na nasz organizm i o czym należy pamiętać stosując ją? Na te i inne pytania odpowiedź będzie można znaleźć w niniejszym artykule.
Vitamin C is said to be essential for the body to function properly. It speeds up the healing process of wounds, activates numerous enzymes, prevents the formation of wrinkles, evens out the natural skin tone, or strengthens teeth and gums by additionally fighting the bacteria that cause decay [2]. What can we expect when we include the youth vitamin in our daily care? How does it affect our body and what should we keep in mind when taking it? These and other questions will be answered in this article.
40, 50, and 60°C with vacuum pressure levels of 0, 40, and 80 kPa. The average drying time decreased by 18.9% and 32.7% as the vacuum pressure and temperature increased, respectively. Six thinlayer models underwent assessment to explain the kinetic process involved in moisture removal using the vacuum heat pump set to provide differing experimental circumstances, and fitted to experimental data. Results showed that the characteristics of moisture removal from the green banana slices could most appropriately be explained by the Page model. There is in increase in effective moisture diffusivity, which ranged from 1.1658×10-10 to 1.9717×10-10 m2 ‧s-1, with increases in temperature and vacuum pressure. Energy of activation ranged from 15.99 to 19.73 kJ‧mol-1, which was explained by an exponential expression based on the Arrhenius models. The drying temperature of 50°C under a vacuum pressure of 80 kPa could preserve the vitamin C content by a maximum of 55.9%, which is the optimal drying condition for obtaining good product quality.
poziomach podciśnienia wynoszących 0,40 i 80 kPa. Średni czas suszenia zmniejszył się o 18,9 i 32,7% gdy podciśnienie i temperatura odpowiednio wzrosły. Sześć modeli o cienkich warstwach poddano ocenie w celu wyjaśnienia procesu kinetycznego, który towarzyszy procesowi usuwania wilgoci za pomocą próżniowej pompy ciepła ustawionej tak, aby zapewnić różnorodne okoliczności doświadczenia i dopasować ją do danych eksperymentalnych. Wyniki pokazały, że właściwości usuwania wilgoci z plastrów zielonego banana mogą być najdokładniej wyjaśnione przy pomocy modelu Page’a. Wystąpił wzrost efektywnej dyfuzji wilgoci, który wahał się w zakresie 1,1658×10-10 do 1,9717×10-10 m2‧s-1, ze wzrostem temperatury i podciśnienia. Energia aktywacji wahała się w zakresie od 15,99 do 19,73 kJ‧mol-1 co zostało wyjaśnione wyrażeniem wykładniczym na podstawie Model Arrheniusa. Temperatura suszenia 50°C w podciśnieniu wynoszącym 80kPa było w stanie zachować witaminę C w 55, 9% co stanowi optymalne warunki suszenia do osiągnięcia wysokiej jakości produktu.
with nitrogen, phosphorus, potassium (NPK) on soils degraded as a result of sulfur extraction. The effectiveness of reclamation was assessed on the basis of changes in the total organic carbon (TOC) content and the properties of humic compounds. The obtained results showed that the use of effective microorganisms in relation to mineral wool and wool used in combination with sewage sludge or NPK causes significant changes in the content and quality of soil organic matter. The observed decrease in the content of TOC, humins and an increase in the share of carbon of labile fractions and free and loosely bound with silicate-free (R2O3) and calcium (Ca) humus forms indicate, that in the soils in which effective microorganisms were used, mineralization processes dominated in the transformation of soil organic matter. The humification process resulted in more durable humic compounds with a higher content of humic acids and humic acids to fulvic acids ratio (C-HA:C-FA). Supplementing commonly used materials in soil reclamation with the introduction of effective microorganisms is a promising technology. Further research is necessary to determine the composition of these biofertilisers and the optimal doses at which they should be used.
safe operation of the aircraft, their assemblies, and units. In some cases, the implementation of inspection or diagnostic is accompanied by the emergence of technical difficulties caused by the large size of the aircraft assemblies or units and limited access to their local places. Under such conditions, ensuring the possibility of diagnosis in hard-to-reach places of the object becomes especially important. The problem can be solved by applying wireless technologies. It allows spatial separation of the probes and the signal processing units, which simplifies the scanning of the surfaces of the large assemblies and units in hard-to-reach places. In this article, the description of the developed wireless system of eddy current inspection for aircraft structural materials is given. Experimental results of object scanning are given in the form of a distribution of the values of probe signal informative parameters (amplitude, frequency and decrement) along the object coordinates.
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