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Tytuł:
Consequences of Mercury Used by Artisanal and Small-Scale Gold Mining Processes a Case of River Nile State Sudan
Autorzy:
Ahmed, Ali M.A.
Purwanto, Purwanto
Sunoko, Henna Rya
Powiązania:
https://bibliotekanauki.pl/articles/124413.pdf
Data publikacji:
2019
Wydawca:
Polskie Towarzystwo Inżynierii Ekologicznej
Tematy:
artisanal gold mining
small-scale gold mining
workers occupationally exposed
WOE
residents in surrounding communities
RSC
distribution of mercury concentration
surface soil
surface water
meteorological factors
topographical factors
Opis:
On the discovery of gold reserves in 14 states in Sudan, traditional gold mining suddenly started to flourish and hundreds of thousands of laymen became engaged in gold extraction. The new source of revenue generation added much to the empty treasury and the loss in petroleum revenue due to cessation of the south in 2011 could thus be compensated. Since gold extraction by artisanal and small-scale gold mining does not require much finance or advanced technology, it suited unskilled workers and many young people found their way into the new business. Although gold extraction generates high revenues, the use of mercury in gold extraction poses much threat to the environment and general health of miners and the surrounding areas. The research tries to investigate the effects of traditional gold mining in Alebedia area, Berber Locality in the River Nile State. The investigation includes A/ the effects of extraction methods on the environment and general health. B/ the level of education and its distribution within the miners and how it affected the awareness of the miners about the dangers of mining activities. C/ the period of stay that miners spend in the mining area its contribution on the awareness about the dangers and diseases inflicted on the miners, D/ the effects of traditional gold mining activities on natural environmental impacts and E/ the effects of the meteorological and topographical factors, the distribution and concentration of mercury in the area and their effects on the environment and general health. The research adopted the techniques of using random sampling and quantitative qualitative in addition to the analytical techniques. The research finally concluded that traditional gold mining has positive effects on the economic side and negative effects on the environment and general health.
Źródło:
Journal of Ecological Engineering; 2019, 20, 2; 106-115
2299-8993
Pojawia się w:
Journal of Ecological Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Social benefits of solar energy: Evidence from Bangladesh
Autorzy:
Salah Uddin, Gazi
Abdullah-Al-Baki, Chowdhury
Park, Donghyun
Ahmed, Ali
Tian, Shu
Powiązania:
https://bibliotekanauki.pl/articles/19905143.pdf
Data publikacji:
2023
Wydawca:
Instytut Badań Gospodarczych
Tematy:
energy transition
solar adaption
clean energy
education
welfare
Bangladesh
Opis:
Research background: The Bangladeshi government has set a plan to generate one-tenth of its electricity from solar and other renewable sources by 2030. Solar adoption surged in Bangladesh up until 2015, setting a global precedent for electrifying areas that were previously unconnected. The enhanced lighting offered by solar systems provides immediate benefits, including additional hours for household and business activities and extended study hours for school-going children. Purpose of the article: This study seeks to identify the determinants and welfare gains of solar adoption in rural areas by analysing three rounds of the Bangladesh Integrated Household Survey from 2011–12, 2015, and 2018–19. In addition to presenting new estimates of economic, environmental, and educational welfare gains, our research offers insights into how solar adoption relates to rural employment and the nutrition of children under five. Methods: We utilized both ordinary least squares and propensity score matching techniques to estimate the welfare effects of solar adoption. Only households that do not use electricity as their primary lighting source, such as those relying on solar or kerosene, are considered in our sample. Findings & value added: We have discovered that adopting solar is linked to higher income, increased expenditure, and growth in asset value. Additionally, there is a significant reduction in kerosene expenditure among adopters compared to non-adopters. Other observations reveal that households with solar setups tend to transition from sharecropping to trading and poultry farming. Children in these households also benefit from solar adoption in terms of education and nutrition. This study illustrates how solar energy can effectively address various welfare concerns in areas where the government cannot supply electricity. Given that recent global events have rendered underdeveloped countries more vulnerable to providing consistent electricity to their entire populations, this research suggests solar energy as a resilient electrification solution during crises.
Źródło:
Oeconomia Copernicana; 2023, 14, 3; 861-897
2083-1277
Pojawia się w:
Oeconomia Copernicana
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Artificial Neural Network for Estimation of Local Scour Depth Around Bridge Piers
Autorzy:
Shakir Ali Ali, Ahmed
Günal, Mustafa
Powiązania:
https://bibliotekanauki.pl/articles/2097766.pdf
Data publikacji:
2021
Wydawca:
Polska Akademia Nauk. Instytut Budownictwa Wodnego PAN
Tematy:
artificial neural network
bridge pier
hydraulics
local scour
Opis:
Local scour around bridge piers impairs the stability of bridges’ structures. Therefore, a delicate estimation of the local scour depth is vital in designing the bridge piers foundations. In this research, MATLAB software was used to train artificial neural network (ANN) models with four hundred laboratory datasets from different laboratory studies, including five parameters: pier diameter, flow depth flow velocity, critical sediment velocity, sediment particle size, and equilibrium local scour depth. The outcomes present that the ANN model with the Levenberg-Marquardt algorithm and 11 nodes in the single hidden layer gives an accurate estimation better than other ANN models trained with different training algorithms based on the regression results and mean squared error values. Besides, the ANN model accurately provides predicted local scour depth and is better than linear and nonlinear regression models. Furthermore, sensitivity analysis shows that removing pier diameter from training parameters diminishes the reliability of prediction.
Źródło:
Archives of Hydro-Engineering and Environmental Mechanics; 2021, 68, 2; 87--101
1231-3726
Pojawia się w:
Archives of Hydro-Engineering and Environmental Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Designing an upper stage steering system for a formula FSAE car
Autorzy:
Wheatley, Greg
Ali, Ahmed
Powiązania:
https://bibliotekanauki.pl/articles/2091236.pdf
Data publikacji:
2021
Wydawca:
Politechnika Śląska. Wydawnictwo Politechniki Śląskiej
Tematy:
design
steering
race car
projekt
układ kierowniczy
samochód wyścigowy
Opis:
The objective of this work is to design an upper stage steering system for the Formula FSAE car “Omega” that will effectively translate driver input force to the rack and pinion. The system consists of a steering wheel, steering shafts, universal joints, a quick release mechanism, and connection points to the car. Critical loads have been determined, and the final design has been validated using finite element analysis to ensure the safety of the assembly during normal operation and worst-scenario cases. The design key factors were performance, weight, cost, ergonomics, maintainability, manufacturability and reliability.
Źródło:
Zeszyty Naukowe. Transport / Politechnika Śląska; 2021, 113; 205--218
0209-3324
2450-1549
Pojawia się w:
Zeszyty Naukowe. Transport / Politechnika Śląska
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Shifter mechanism design for FSAE motor sports vehicle JCU
Autorzy:
Wheatley, Greg
Ali, Ahmed
Powiązania:
https://bibliotekanauki.pl/articles/2091242.pdf
Data publikacji:
2021
Wydawca:
Politechnika Śląska. Wydawnictwo Politechniki Śląskiej
Tematy:
mechanical shifter
solid linkage
spline attachments
FEA
mechaniczna skrzynia biegów
trwałe połączenie
mocowanie wielowypustowe
MES
Opis:
This report provides a design analysis of a replacement’s shifter mechanism for the 2014 model JCU Motorsports FSAE vehicle. Common FSAE shifter mechanisms were researched and reviewed to provide a better understanding of the needs required. A design approach was constructed to ultimately design a mechanism that conformed to all existing constraints and FSAE rules. Realistic load cases were identified and employed in the FEA analysis of the design. Supporting hand calculations were developed, proving the analysis to be accurate. Results showed the shifter mechanism does not fail under infinite life, with some parts of the design having a reasonably high safety factor, ensuring stability.
Źródło:
Zeszyty Naukowe. Transport / Politechnika Śląska; 2021, 113; 219--229
0209-3324
2450-1549
Pojawia się w:
Zeszyty Naukowe. Transport / Politechnika Śląska
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Enhancing the flexural load capacity of the reinforced concrete simply supported slabs using damaged tires strips (DTS)
Autorzy:
Ali, Saba
Alalikhan, Ahmed
Powiązania:
https://bibliotekanauki.pl/articles/35556446.pdf
Data publikacji:
2022
Wydawca:
Szkoła Główna Gospodarstwa Wiejskiego w Warszawie. Wydawnictwo Szkoły Głównej Gospodarstwa Wiejskiego w Warszawie
Tematy:
flexural strength
reinforced concrete slabs
damaged tires strips
Opis:
Damaged tires or ended-life tires represent a difficult problem due to their ability to sustain for a long time which are not able to be dissolved easily. Present study focuses on the ability of using the damaged tires strips (DTS) in the field of structural engineering as an innovative reinforcing material used additionally with the main reinforcement. The adopted technique in the present work represents a clean solution to reuse and recycle DTS to increase the ultimate flexural capacity of the reinforced concrete one-way and two-way slabs used in structural systems satisfying clean environment and economic considerations. The tests were conducted upon eight specimens of reinforced concrete one-way slabs (RCOWS) and two specimens of reinforced concrete two-way slabs (RCTWS) reinforced by the DTS as an additional reinforcement. Experimentally obtained results exhibited enhancement for the ultimate flexural load capacity of the RCOWS and RCTWS models reinforced by the DTS in the range of 16–80 and 14.28% respectively, compared to the original reference specimens.
Źródło:
Scientific Review Engineering and Environmental Sciences; 2022, 31, 2; 101-112
1732-9353
Pojawia się w:
Scientific Review Engineering and Environmental Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Improved CSE with DLS-MMSE Criteria in TH-UWB System
Autorzy:
Djebbari, Ali
Elahmar, Sid Ahmed
Powiązania:
https://bibliotekanauki.pl/articles/2058501.pdf
Data publikacji:
2022
Wydawca:
Instytut Łączności - Państwowy Instytut Badawczy
Tematy:
channel shortening equalizer
inter-symbol interferences
rake receiver
time hopping
ultra-wide band
ZF-MMSE
Opis:
This article presents a study on the use of deter ministic least squares criteria combined with the minimum mean square error method for the purpose of computing filter coefficients of the channel shortening equalizer. This method is well known to alleviate inter-symbol interference in time hopping UWB systems. The validity of this method is applied to shorten the impulse response of the effective UWB channels and, therefore, reduce the complexity of the rake receiver. Results show a very promising advantage compared to partial rake (P-Rake), selective-rake (S-Rake) and optimal maximum shortening signal-to-noise ratio methods.
Źródło:
Journal of Telecommunications and Information Technology; 2022, 1; 93--98
1509-4553
1899-8852
Pojawia się w:
Journal of Telecommunications and Information Technology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Evaluating the connectivity level of Fayoum city roads network: a new method using GIS
Ocena poziomu spójności sieci dróg miejskich Fayoum: nowa metoda wykorzystująca GIS
Autorzy:
Saleh, Ahmed Younes
Abdu, Saeed Ahmed
Ali, Hanaa Nazer
Powiązania:
https://bibliotekanauki.pl/articles/2089773.pdf
Data publikacji:
2018
Wydawca:
Uniwersytet Gdański. Komisja Geografii Komunikacji Polskiego Towarzystwa Geograficznego
Tematy:
connectivity level
GIS
map algebra
network analysis
urban road network
poziom spójności
algebra mapy
analiza sieci
sieć dróg miejskich
Opis:
Road networks within cities are a vital component of the socio-economic development processes. Many countries have sought to examine and evaluate the efficiency of road networks within urban areas because of the increasing demand for transportation. Thus, networks should be evaluated to guide the development of transport systems and infrastructure within cities. This study evaluates the connectivity level of the road network parts in Fayoum city, Egypt, through the application of some indicators of connectivity measurement, such as Beta, Alpha, Gamma, Connectivity degree, and the density of edges and nodes. The study follows a new method for evaluation; it does not apply the indicators on the network as a whole; however, it divides the city into zones and calculates the indicators of each zone using the Arc GIS 10.2.1 program. The authors applied the map Algebra method to map the results of the six indicators in one index called the Total Connectivity Index (TCI). The TCI gives more consistent results than other indices, and it is more related to different spatial patterns of roads. According to this indicator, most of the city road network seem to have a good connectivity level, whereas the city marginal areas prove to have a poor connectivity level. Therefore, any efforts to develop or construct new roads should be in the marginal areas of the city.
Źródło:
Prace Komisji Geografii Komunikacji PTG; 2018, 21(4); 60-72
1426-5915
2543-859X
Pojawia się w:
Prace Komisji Geografii Komunikacji PTG
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Desulfurization of Crude Oil by Laboratory Developed Multipumping Flow Injection Analysis System with Optimization by Response Surface Methodology
Autorzy:
Hadi, Ahmed Abdulrazzaq
Ali, Ali Abdulkhabeer
Khathi, Mohammed Turki
Powiązania:
https://bibliotekanauki.pl/articles/2202370.pdf
Data publikacji:
2023
Wydawca:
Polskie Towarzystwo Inżynierii Ekologicznej
Tematy:
multi-pumping flow system
desulfurisation
response surface
optimal conditions
Opis:
Sour crude oil is the crude oil that contains a high level of sulfur impurity. It can be toxic and corrosive. Before this lower-quality crude can be processed into other crude oil derivatives, the sulfur content must be reduced, raising the processing cost. A homemade semi-automated multipumping flow analysis system was constructed, consisting of several parts available on the local markets and at low economic costs to decrease the sulfur content of crude oil samples collected. The central composite design (CCD) and response surface methodology (RSM) have been used for modeling and optimization. The effects of the operational parameters, including polar and nonpolar solvent types, solvent flow rates (10–40 ml/min), mixing coil lengths (120–200 min), temperature (30–60 °C), and solvent entry time to the system (0–60 sec) were studied. Experimental and theoretical applications were made to determine the optimal sulfur content, which came out to be 1.438 and 1.395 wt.%, respectively. This system evaluated the effectiveness of the sulfur removal content for actual heavy crude oil by experimentally and theoretically to be 65.73 and 66.75% respectively. The semi-automated system was applied successfully to reduce the sulfur content in a highly sensitive and accurate way.
Źródło:
Journal of Ecological Engineering; 2023, 24, 2; 328--339
2299-8993
Pojawia się w:
Journal of Ecological Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Novel approach for big data classification based on hybrid parallel dimensionality reduction using spark cluster
Autorzy:
Ali, Ahmed Hussein
Abdullah, Mahmood Zaki
Powiązania:
https://bibliotekanauki.pl/articles/305766.pdf
Data publikacji:
2019
Wydawca:
Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH
Tematy:
big data
dimensionality reduction
parallel processing
Spark
PCA
LDA
Opis:
The big data concept has elicited studies on how to accurately and efficiently extract valuable information from such huge dataset. The major problem during big data mining is data dimensionality due to a large number of dimensions in such datasets. This major consequence of high data dimensionality is that it affects the accuracy of machine learning (ML) classifiers; it also results in time wastage due to the presence of several redundant features in the dataset. This problem can be possibly solved using a fast feature reduction method. Hence, this study presents a fast HP-PL which is a new hybrid parallel feature reduction framework that utilizes spark to facilitate feature reduction on shared/distributed-memory clusters. The evaluation of the proposed HP-PL on KDD99 dataset showed the algorithm to be significantly faster than the conventional feature reduction techniques. The proposed technique required >1 minute to select 4 dataset features from over 79 features and 3,000,000 samples on a 3-node cluster (total of 21 cores). For the comparative algorithm, more than 2 hours was required to achieve the same feat. In the proposed system, Hadoop’s distributed file system (HDFS) was used to achieve distributed storage while Apache Spark was used as the computing engine. The model development was based on a parallel model with full consideration of the high performance and throughput of distributed computing. Conclusively, the proposed HP-PL method can achieve good accuracy with less memory and time compared to the conventional methods of feature reduction. This tool can be publicly accessed at https://github.com/ahmed/Fast-HP-PL.
Źródło:
Computer Science; 2019, 20 (4); 411-429
1508-2806
2300-7036
Pojawia się w:
Computer Science
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Differential designing for FSAE motor sports vehicle JCU
Autorzy:
Marciano, Pieta
Wheatley, Greg
Ali, Ahmed
Powiązania:
https://bibliotekanauki.pl/articles/2173482.pdf
Data publikacji:
2022
Wydawca:
Politechnika Śląska. Wydawnictwo Politechniki Śląskiej
Tematy:
torque transition
shaft system
FEA
przejście momentu obrotowego
układ wałów
Opis:
The objective of this work was to design a differential assembly for an FSAE motor sports vehicle. The designed differential system consists of 3 braces made of AISI 1045 steel. The output shafts were made of AISI 4140 steel with hardened splines. These shafts were initially going to drive 94 mm constant velocity shafts. A 75 mm tripod joint was used to minimize the weight and cost of the system. The housing was held together with grade 12.8 hex head bolts, and the shafts were bolted onto the tri-pod joints using bolts of grade 8.8 which complies with FSAE rules. The input shaft which acts on the differential itself is made of EN36A steel and is where the drive sprocket is bolted to. All components were modeled using Finite Element Analysis to determine stresses and displacements under operating conditions.
Źródło:
Zeszyty Naukowe. Transport / Politechnika Śląska; 2022, 114; 67--78
0209-3324
2450-1549
Pojawia się w:
Zeszyty Naukowe. Transport / Politechnika Śląska
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Rola ultrasonografii w rozpoznawaniu utajonych złamań kości łódeczkowatej
The role of ultrasonography in the diagnosis of occult scaphoid fractures
Autorzy:
Ali, Mohammed
Ali, Mujtaba
Mohamed, Ahmed
Mannan, Syed
Fallahi, Farshid
Powiązania:
https://bibliotekanauki.pl/articles/1032202.pdf
Data publikacji:
2018
Wydawca:
Medical Communications
Tematy:
złamanie kości łódeczkowatej
Opis:
Background: Ultrasonography is widely utilized by emergency physicians and radiologists to diagnose various orthopaedic diseases, including fractures. We aim to derive a definitive estimate of the diagnostic accuracy of ultrasonography in clinically suspected scaphoid fractures. Methods: We undertook a systematic review and meta-analysis of included diagnostic cohort studies that discussed the use of ultrasonography in the diagnosis of occult scaphoid fractures. We searched the National Institute for Health and Care Excellence database using the Healthcare Databases Advanced Search tool. In addition, we utilized the PubMed database to search the Medical Literature Analysis and Retrieval System Online, Excerpta Medica database, Cumulative Index of Nursing and Allied Health and Allied and Complimentary Medicine databases. Studies were included if they discuss the role of ultrasound imaging in the diagnosis of scaphoid fractures based on cortical interruption, radio-carpal effusion and scapho-trapezium-trapezoid effusion. Quality assessment was performed using the methodological index for non-randomized studies scoring system. Results: 6 non-randomized control studies met the inclusion criteria. Collectively, these included 236 patients with a mean age ranging from 18 to 41.2 years. The quality of these articles ranged between moderate and high based on the methodological index for nonrandomized studies score. The mean sensitivity was 88.95% (standard deviation 10.03) and mean specificity was 89.50% (standard deviation 12.21). Conclusion: The current literature reveals high sensitivity and specificity in the use of ultrasonography in scaphoid fracture diagnosis. However, multiple factors including technical differences in ultrasound machines and probes, small sample sizes and variability of subsequent confirmatory tests have created a challenge in determining the ultimate reliability of ultrasonography in the diagnosis of occult scaphoid fractures. Considering these factors and limitations, large-sample and high-quality clinical trials are needed to adequately assess its reliability for this purpose. One stop clinics, in the authors’ opinion, would be an ideal setting for its introduction as well as for future trials.
Wprowadzenie: Ultrasonografia jest szeroko wykorzystywana w medycynie ratunkowej i radiologii do diagnozowania różnych schorzeń narządu ruchu, w tym złamań. Celem pracy jest jednoznaczne ustalenie stopnia dokładności badania ultrasonograficznego w przypadku klinicznego podejrzenia złamania kości łódeczkowatej. Metody: W pracy podjęto się przeglądu systematycznego i metaanalizy wybranych badań kohortowych, które dotyczą wykorzystania ultrasonografii w rozpoznawaniu utajonych złamań kości łódeczkowatej. Przeszukano bazę National Institute for Health and Care Excellence z wykorzystaniem narzędzia wyszukiwania Healthcare Databases Advanced Search. Wykorzystano również bazę PubMed do przeszukania baz danych Medical Literature Analysis and Retrieval System Online, Excerpta Medica, Cumulative Index of Nursing and Allied Health oraz Allied and Complimentary Medicine Database. Do analizy włączano te badania, które dotyczą roli badania ultrasonograficznego w rozpoznawaniu złamań kości łódeczkowatej na podstawie przerwania ciągłości istoty zbitej, wysięku w stawie promieniowo-nadgarstkowym oraz wysięku w stawie łódeczkowato-czworobocznym. Oceny jakości analizowanych prac dokonywano na bazie klasyfikacji punktowej badań nierandomizowanych. Wyniki: Kryteria włączenia spełniło 6 badań porównawczych bez randomizacji. Badania te obejmowały łącznie 236 pacjentów o średniej wieku od 18 lat do 41,2 roku. Jakość artykułów wahała się pomiędzy średnią a wysoką na podstawie wyniku w klasyfikacji punktowej badań nierandomizowanych. Średnia czułość badania w analizowanych pracach wynosiła 88,95% (odchylenie standardowe: 10,03), a średnia swoistość 89,50% (odchylenie standardowe: 12,21). Wnioski: Najnowsze doniesienia literaturowe mówią o wysokiej czułości i swoistości badania ultrasonograficznego w rozpoznawaniu złamania kości łódeczkowatej. Ustalenie wiarygodności badania ultrasonograficznego w rozpoznawaniu utajonych złamań kości łódeczkowatej jest jednak trudne ze względu na liczne czynniki, takie jak różnice techniczne pomiędzy stosowanymi aparatami i głowicami ultrasonograficznymi, niska liczebność badanych prób oraz różnice w typie badania stosowanego do potwierdzenia rozpoznania. Ze względu na te czynniki i ograniczenia do właściwej oceny wiarygodności badania ultrasonograficznego stosowanego do omawianego celu potrzebne są badania kliniczne wysokiej jakości. Według autorów ośrodki kompleksowej diagnostyki typu „one stop clinic” byłyby idealnym miejscem na wprowadzenie badań ultrasonograficznych do diagnostyki złamań kości łódeczkowatej oraz na prowadzenie badań klinicznych w przyszłości.
Źródło:
Journal of Ultrasonography; 2018, 18, 75; 325-331
2451-070X
Pojawia się w:
Journal of Ultrasonography
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Structural analysis of functionally graded material using sigmioadal and power law
Autorzy:
Abd-Ali, Nabel Kadum
Madeh, Ahmed Raee
Powiązania:
https://bibliotekanauki.pl/articles/1955209.pdf
Data publikacji:
2021
Wydawca:
Polska Akademia Nauk. Polskie Towarzystwo Diagnostyki Technicznej PAN
Tematy:
FGM shell
sigmoidal law
power law
Hamilton’s principle
stress analysis
prawo sigmoidalne
zasada Hamiltona
analiza naprężeń
Opis:
The stress-strain relations, displacement distribution, stress resultants and mid plane strain resultants of a functionally graded material plate are studied using Hamilton’s principle. A simply supported rectangular thick shell direct stress, inplane shear stress, transverse stress and displacement are investigated. The analysis and modeling of five layers FGM shell is carried out using MATLAB19 code with ABAQUS20 software. Using distinct materials on the top and bottom layers of the shell, a transverse uniform load in five degrees - of - freedom is applied with a specific Poisson's ratio and Young's modulus in a power and sigmoidal law function through the thickness direction. A power law was used to determine the distribution of properties through shell thickness. The results showed that the bottom layer affected significantly most stress due to subjected to the most in-plane stress while the displacement is greatest at the top layer.
Źródło:
Diagnostyka; 2021, 22, 4; 59-65
1641-6414
2449-5220
Pojawia się w:
Diagnostyka
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The stress analysis effect on structural health monitoring in functionally graded shell
Autorzy:
Madeh, Ahmed Raee
Abd-Ali, Nabel Kadum
Powiązania:
https://bibliotekanauki.pl/articles/2096204.pdf
Data publikacji:
2022
Wydawca:
Polska Akademia Nauk. Polskie Towarzystwo Diagnostyki Technicznej PAN
Tematy:
health monitoring
FG shell
power law
sigmoidal law
virtual energy method
thickness ratio
monitorowanie konstrukcji
prawo energetyczne
prawo sigmoidalne
Opis:
The common damage in engineering structures, especially in functionally graded materials, such as failure resulting from fiber breaking or cracking in the matrix or deboning between fibers and matrix, as well as the delamination between the composite material plies and between its layers, may be due to thermal effects, vibration, load concentration as a result of stress and strain for provides information’s about structural health monitoring. Virtual energy method such as Hamilton's was used to investigate the effect of the design parameters such as side to thickness and modular as well as material graduation index ratio on the stress-strain relationships, displacement, resultants of stresses, and resultants of mid plane strain. The analysis and simulation of the FGM shells is done in this paper utilizing MATLAB19 code and ABAQUS20 programs. The distribution of characteristics across shell thickness had also been determined using a power law. Normal stress was varied gradually from 5.74 MPa to 9.55 MPa with material index (n) from 0 to 10 respectively, while shear stress varied from 4.2 to 8.23 MPa for the same value of (n). The strain percent increased slightly from 0.00059 to 0.0012 with displacement 0.22 and 1.2 respectively for the same value of (n).
Źródło:
Diagnostyka; 2022, 23, 3; art. no. 2022302
1641-6414
2449-5220
Pojawia się w:
Diagnostyka
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Health monitoring of composite car roof failure under effect of different impact velocity
Autorzy:
Madeh, Ahmed Raee
Abd-Ali, Nabel Kadum
Powiązania:
https://bibliotekanauki.pl/articles/27313827.pdf
Data publikacji:
2023
Wydawca:
Polska Akademia Nauk. Polskie Towarzystwo Diagnostyki Technicznej PAN
Tematy:
failure index
Tsai-Wu
health monitoring
car roof
stress analysis
wskaźnik uszkodzeń
dach samochodu
analiza naprężeń
uderzenie
Opis:
During this work, the roof of the car was used as an engineering application to study and monitor the occurrence of failures under the influence of various loads. The shells are made of multilayer composite materials using epoxy resin reinforced with carbon fiber and aluminium oxide granules as reinforcing materials to increase the impact resistance that vehicles may be exposed to while driving, in addition to other loads and conditions such as vibration and constant exposure to moisture and sunlight. The simulation program was used the finite elements method through software Abaqus program in addition to the program MATLAB v.2020a to process the data obtained from the method that used in this study. The results showed that the specified failure criteria work well for predicting the overall structural response such as strain, stress, maximum force and displacement. The losses of energy of impact collision increase as an increase in impact velocity. The dissipation of energy which depend on the stress and strain distribution during elastic deformations. The effect of thickness of the lamina plays an important role in health monitoring the structure.
Źródło:
Diagnostyka; 2023, 24, 4; art. no. 2023406
1641-6414
2449-5220
Pojawia się w:
Diagnostyka
Dostawca treści:
Biblioteka Nauki
Artykuł
Wyświetlanie 1-15 z 56

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