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Tytuł:
A New Approach of an Error Detecting and Correcting Circuit by Arithmetic Logic Blocks
Autorzy:
Kavitha, S.
Hashim, Fazida Hanim
Kamal, Noorfazila
Powiązania:
https://bibliotekanauki.pl/articles/226549.pdf
Data publikacji:
2019
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
EDAC
ALU
speed
block reduction
power
slew rate
Opis:
This paper proposes a unique method of an error detection and correction (EDAC) circuit, carried out using arithmetic logic blocks. The modified logic blocks circuit and its auxiliary components are designed with Boolean and block reduction technique, which reduced one logic gate per block. The reduced logic circuits were simulated and designed using MATLAB Simulink, DSCH 2 CAD, and Microwind CAD tools. The modified, 2:1 multiplexer, demultiplexer, comparator, 1-bit adder, ALU, and error correction and detection circuit were simulated using MATLAB and Microwind. The EDAC circuit operates at a speed of 454.676 MHz and a slew rate of -2.00 which indicates excellence in high speed and low-area.
Źródło:
International Journal of Electronics and Telecommunications; 2019, 65, 2; 313-318
2300-1933
Pojawia się w:
International Journal of Electronics and Telecommunications
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Assessment on the Physical, Mechanical Properties and Leaching Behaviour of Fired Clay Brick Incorporated with Steel Mill Sludge
Autorzy:
Sarani, Noor Amira
Hashim, Azini Amiza
Kadir, Aeslina Abdul
Hissham, Nur Fatin Nabila
Hassan, Mohd Ikhmal Haqeem
Nabiałek, Marcin
Jeż, Bartłomiej
Powiązania:
https://bibliotekanauki.pl/articles/2048828.pdf
Data publikacji:
2022
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
building materials
leachability
fired clay brick
steel mill sludge
brick properties
Opis:
The disposal of industrial steel mill sludge in landfills has frequently received significant concern as the sludge has a very notable potential to contaminate soil surface and groundwater in the long run. Recently, the incorporation of industrial steel mill sludge into fired clay brick has become one of the promising alternative methods as it could produce a lightweight product while minimizing the environmental impact of the waste used. In this study, fired clay bricks as the most common building material were incorporated with 0%, 5%, 10% and 15% of steel mill sludge and fired at 1050°C (heating rate of 1°C/min). The manufactured bricks were subjected to physical and mechanical properties such as firing shrinkage, dry density, and compressive strength while the Toxicity Characteristic Leaching Procedure (TCLP) was conducted to analyze leaching behavior from the manufactured bricks. The results demonstrated that incorporation up to 15% of steel mill sludge reduces the properties up to 27.3% of firing shrinkage, 8.1% of dry density and 67.3% of compressive strength. The leaching behavior of Zn and Cu from steel mill sludge was reduced up to 100% from 7414 to 9.22 ppm (Zn) and 16436 to 4.654 ppm (Cu) after 15% of sludge incorporation. It was observed that high temperature during the firing process would improve the properties of bricks while immobilizing the heavy metals from the waste. Therefore, recycling steel mill sludge into construction building materials could not only alleviate the disposal problems but also promote alternative new raw materials in building industries.
Źródło:
Archives of Metallurgy and Materials; 2022, 67, 1; 209-214
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Characterization of Magnetosomes After Exposure to the Effect of the Sonication and Ultracentrifugation
Autorzy:
Molčan, M.
Hashim, A.
Kováč, J.
Rajňák, M.
Kopčanský, P.
Makowski, M.
Gojzewski, H.
Molokáč, M.
Hvizdák, L.
Timko, M.
Powiązania:
https://bibliotekanauki.pl/articles/1368025.pdf
Data publikacji:
2014-07
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
81.07.-b
75.60.-d
87.50.Y-
68.37.-d
Opis:
Magnetosomes are intracellular organelles of widespread aquatic microorganisms called Magnetotactic bacteria. At present they are under investigation especially in biomedical applications. This ability depends on the presence of intracellular magnetosomes which are composed of two parts: first, nanometer-sized magnetite $(Fe_{3}O_{4})$ or greigite $(Fe_{3}S_{4})$ crystals (magnetosome crystal), depending on the bacterial species; and second, the bilayer membrane surrounding the crystal (magnetosome membrane). The magnetosomes were prepared by biomineralization process of magnetotactic bacteria Magnetospirillum Magnetotacticum sp. AMB-1. The isolated magnetosome chains (sample M) were centrifugated at speed of 100000 rpm for 4 hours (sample UM) and sonicated at power of 120 W for 3 hours (sample SM), respectively. The prepared suspensions were investigated with respect to morphological, structural and magnetic properties. The results from scanning electron microscopy showed that isolated chains of magnetosomes were partially broken to smaller ones after ultracentrifugation. On the other hand the application of the sonication process caused the formation of individual magnetosomes (unordered in chain). These results were confirmed by coercivity and magnetization saturation measurements.
Źródło:
Acta Physica Polonica A; 2014, 126, 1; 198-199
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Design of a Predictive PID Controller Using Particle Swarm Optimization
Autorzy:
Mustafa, Norhaida
Hashim, Fazida Hanim
Powiązania:
https://bibliotekanauki.pl/articles/1844451.pdf
Data publikacji:
2020
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
proportional integral derivative controller
particle swarm optimization (PSO) algorithm
optimization
predictive PID
Opis:
The proportional-integral-derivative (PID) controller is widely used in various industrial applications such as process control, motor drives, magnetic and optical memory, automotive, flight control and instrumentation. PID tuning refers to the generation of PID parameters (Kp, Ki, Kd) to obtain the optimum fitness value for any system. The determination of the PID parameters is essential for any system that relies on it to function in a stable mode. This paper proposes a method in designing a predictive PID controller system using particle swarm optimization (PSO) algorithm for direct current (DC) motor application. Extensive numerical simulations have been done using the Mathwork’s Matlab simulation environment. In order to gain full benefits from the PSO algorithm, the PSO parameters such as inertia weight, iteration number, acceleration constant and particle number need to be carefully adjusted and determined. Therefore, the first investigation of this study is to present a comparative analysis between two important PSO parameters; inertia weight and number of iteration, to assist the predictive PID controller design. Simulation results show that inertia weight of 0.9 and iteration number 100 provide a good fitness achievement with low overshoot and fast rise and settling time. Next, a comparison between the performance of the DC motor with PID-PSO, with PID of gain 1, and without PID were also discussed. From the analysis, it can be concluded that by tuning the PID parameters using PSO method, the best gain in performance may be found. Finally, when comparing between the PID-PSO and its counterpart, the PI-PSO, the PID-PSO controller gives better performance in terms of robustness, low overshoot (0.005%), low minimum rise time (0.2806 seconds) and low settling time (0.4326 seconds).
Źródło:
International Journal of Electronics and Telecommunications; 2020, 66, 4; 737-743
2300-1933
Pojawia się w:
International Journal of Electronics and Telecommunications
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Design of Municipal Solid Waste Landfill for Baghdad City
Autorzy:
Takrid, Munaem Nafae
Haydar, Ahmed Al-Najar
Nabeel, Hashim Ameen Al-Tameemi
Huda, Nassar Karkoush
Powiązania:
https://bibliotekanauki.pl/articles/1178769.pdf
Data publikacji:
2017
Wydawca:
Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Tematy:
Municipal solid waste generation rate
landfill
Opis:
Accumulation of municipal solid waste in residential areas is one of the public health problems in Iraq. In the other hand, accurate and reliable information on solid waste generation rate are very important elements to plan and implement solid waste management system. The volume and surface area required for a landfill to dispose the municipal solid wastes generated in Baghdad city is evaluated in this study. The per capita solid wastes generation rates are measured for a family consists of 10 individuals by using portable balance (Salter, 0 to 130 kg). Probability sampling is used to determine the minimum number of measurements needed to evaluate the mean of per capita solid wastes generation rate with a certain level of precision (a specified error level of 5% is selected corresponds to 95% confidence that the mean value is in accurate estimate of the true value). The results indicate that an area of approximately 1603 m on a side is required for the next 20 years as a sanitary landfill for disposing the municipal solid wastes generated in Baghdad city.
Źródło:
World Scientific News; 2017, 90; 1-10
2392-2192
Pojawia się w:
World Scientific News
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Distribution of total petroleum hydrocarbons and polycyclic aromatic hydrocarbons in Musa Bay sediments (northwest of the Persian Gulf)
Autorzy:
Tehrani, G. M.
Hashim, R.
Sulaiman, A. H.
Sany, S. B. T.
Salleh, A.
Jazani, R. K.
Savari, A.
Barandoust, R. F.
Powiązania:
https://bibliotekanauki.pl/articles/207391.pdf
Data publikacji:
2013
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
polycyclic aromatic hydrocarbons
PAH
petroleum chemistry
coastal area
hydrocarbon contamination
Persian Gulf
special economic zones
petroleum hydrocarbons
wielopierścieniowe węglowodory aromatyczne
WWA
ropa naftowa
pas przybrzeżny
zanieczyszczenia węglowodorami
Zatoka Perska
specjalna strefa ekonomiczna
węglowodory ropopochodne
zanieczyszczenia ropopochodne
zanieczyszczenia substancjami ropopochodnymi
Opis:
Sediment samples were collected from the coastal area of the Petrochemical Special Economic Zone of Musa Bay. The samples were analyzed to determine the degree of hydrocarbon contamination and identify the sources of PAHs which were evaluated by employing the ratios of specific PAHs compounds and principal component analysis (PCA). The levels of TPH concentration in the studied area were relatively moderate compared to the world-wide chronically oil-contaminated locations. The concentration of total PAHs was lower than those in other parts of the Musa Bay but approached the NOAA sediment quality guideline value.
Źródło:
Environment Protection Engineering; 2013, 39, 1; 115-128
0324-8828
Pojawia się w:
Environment Protection Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effect of Composition on Melt Flow and Density of Polypropylene Copolymer/Kaolin Geo-Filler Composites
Autorzy:
Zulkifli, Zulaikha
Daud, Yusrina Mat
Zainal, Farah Farhana
Hashim, Mohammad Firdaus Abu
Aygörmez, Yurdakul
Powiązania:
https://bibliotekanauki.pl/articles/2203755.pdf
Data publikacji:
2023
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
geo-filler
kaolin
composites
polypropylene
rheological
Opis:
This study examined the effects rheological properties of different composition kaolin and kaolin geo-filler in polypropylene composites. Polypropylene composites with varying composition of kaolin geo-filler 0 wt%, 2 wt%, 4 wt%, 6 wt%, 8 wt%, and 10 wt% was prepared and compared with polypropylene composite with raw kaolin. Kaolin is an aluminosilicate based mineral filler was used to prepare geopolymer paste by combining with alkaline activator solution. The polypropylene composite was compounded using a twin-screw extruder and the melt flow index was determined by a constant weight pressure of 2.16 kg at 230°C in 10 min. Knowing the melt flow index is necessary to predict and control the process, the study has demonstrated that the composition of kaolin filler and kaolin geo-filler affects the melt flow, melt density and surface morphology at varies composition. Composites with kaolin geo-filler have demonstrated high melt flow index process and having better distribution and flow.
Źródło:
Archives of Metallurgy and Materials; 2023, 68, 1; 369--373
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effect of KCl on the optical and structural properties of CaZnO3 perovskite thin films
Wpływ KCl na właściwości optyczne i strukturalne cienkich warstw perowskitu CaZnO3
Autorzy:
Al-Saqa, Read Hashim
Jassim, Ismail Kalil
Uonis, Mohammad Mahmood
Powiązania:
https://bibliotekanauki.pl/articles/41159232.pdf
Data publikacji:
2023
Wydawca:
Wydawnictwo SIGMA-NOT
Tematy:
CaZnO3
perovskite
energy gap
diameter’s grain
perowskit
przerwa energetyczna
średnica ziarna
cienkie warstwy
Opis:
The primary goal of this study is to determine whether the produced CaZnO3 perovskite compound may be used in the production of solar cells and diodes. CaZnO3 perovskite thin films have been prepared and examined using scanning electron microscopy (SEM), X-ray spectroscopy, and UV spectroscopy. The films were made using the chemical spray pyrolysis deposition (CSPD) method; they were prepared from a mixture of 0.6 g of CaCl2 and ZnCl2 with 1.2 g of KOH, and CaZnO3 thin films were deposited on a glass substrate at a temperature of 150°C. Optical properties such as transmittance (T), absorbance (A), reflectance (R), the refractive index (n), and extinction coefficient (k) were studied. The energy gap varied from 3.19 eV for films without KCl to 3.22 eV for films with KCl, indicating that the presence of KCl had an impact on the energy gap; furthermore, the average particle’s diameter for films with KCl was about 112.28 nm and decreased to 53.86 nm when KCl was removed from the solutions to obtain pure in CaZnO3 perovskite thin films.
Wpływ KCl na właściwości optyczne i strukturalne cienkich warstw perowskitu CaZnO3 Głównym celem badania było określenie, czy wytworzony perowskitowy związek CaZnO3 może zostać wykorzystany do produkcji ogniw fotowoltaicznych i diod. Przygotowano cienkie warstwy perowskitu CaZnO3, które zostały zbadane za pomocą skaningowego mikroskopu elektronowego (SEM), spektrometru rentgenowskiego i spektrometru UV. Warstwy zostały wykonane przy użyciu metody chemicznego osadzania pirolitycznego (CSPD); przygotowano je z mieszaniny 0,6 g CaCl2 i ZnCl2 z 1,2 g KOH, cienkie warstwy CaZnO3 osadzono na szklanym podłożu w temperaturze 150°C. Zbadano właściwości optyczne, takie jak transmitancja (T), absorbancja (A), współczynnik odbicia (R), współczynnik załamania światła (n) i współczynnik ekstynkcji (k). Przerwa energetyczna wynosiła od 3,19 eV w wypadku warstw bez KCl do 3,22 eV dla warstw z KCl, co świadczy o tym, że obecność KCl miała wpływ na przerwę energetyczną. Średnica cząstek w warstwach zawierających KCl wynosiła średnio 112,28 nm i zmniejszyła się do 53,86 nm, gdy z roztworów usunięto KCl w celu uzyskania czystych postaci cienkich warstw CaZnO3.
Źródło:
Ochrona przed Korozją; 2023, 8; 243-246
0473-7733
2449-9501
Pojawia się w:
Ochrona przed Korozją
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effect of vortex runner gating system on the mechanical strength of Al-12SI alloy castings
Wpływ kanału układu wlewowego na wytrzymałość mechaniczną odlewów ze stopu Al-12Si
Autorzy:
Ahmad, R.
Hashim, M. Y.
Powiązania:
https://bibliotekanauki.pl/articles/352629.pdf
Data publikacji:
2011
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
odlewy piaskowe
wytrzymałość mechaniczna
analiza Weibulla
układ wlewowy
gating systems
sand casting
mechanical strength
Weibull analysis
Opis:
Gating system design is an essential element in casting process which affects significantly the molten metal flow behavior, heat transfer and solidification of the melt. Optimum gating design will lead to a good quality of casting product. One of the major components in gating system is runner. This study was conducted to determine the effect of vortex runner diameter gating system on the mechanical strength of Al-12Si alloy casting. Simulation was conducted to study the behavior of the fluid flow and the results obtained showed close agreement with the results obtained from the experiment. Experimental results showed that the casting product with bigger vortex runner diameter gating system led to the improvement of average bending strength.
Układ wlewowy to podstawowy element w procesie odlewania, który znacząco wpływa na płynięcie ciekłego metalu, transport ciepła oraz krzepnięcie metalu. Optymalny układ wlewowy gwarantuje dobra jakość odlanego produktu. Jednym z głównych elementów układu wlewowego jest kanał wlewowy. Celem pracy było zbadanie wpływu średnicy kanału układu wlewowego na wytrzymałosc mechaniczna odlewów ze stopu Al-12Si. Celem zbadania zachowania przecieczy przeprowadzono symulacje i otrzymane wyniki wykazują dobrą zgodność z wynikami otrzymanymi doświadczalnie. Wyniki doswiadczeń pokazały, że zastosowanie większej srednicy kanału układu wlewowego prowadzi do poprawy średniej wytrzymałości odlewów na zginanie.
Źródło:
Archives of Metallurgy and Materials; 2011, 56, 4; 991-991
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effects of Intra-Row Spacing of Pearl Millet (Pennisetum glaucum (L.) R.Br.) and Cropping Systems on Growth and Yields of Soybean-Pearl Millet Intercrop, in the Southern Guinea Savanna, Nigeria
Autorzy:
Ijoyah, Michael Ojore
Hashim, Ishaya Kunzan
Idoko, Joseph Adakole
Powiązania:
https://bibliotekanauki.pl/articles/1190199.pdf
Data publikacji:
2016
Wydawca:
Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Tematy:
spacing
intercropping
pearl millet
soybean
Nigeria
Opis:
Field experiments were separately conducted from June to November, in year 2012 at the Research Farm, University of Agriculture, Makurdi, Nigeria and at a Farm in Ibi, Nigeria, to evaluate the effects of intra-row spacing of pearl millet and cropping systems on growth and yields of soybean-pearl millet intercrop, as well as assessing the yield advantages of the intercropping system. The experiment was a 2 x 4 factorial combination of treatments, fitted in a randomized complete block design (RCBD), with four replications. The cropping systems constitute the soles and the intercrop, while the intra-row spacing of pearl millet into soybean were at 15 cm, 20 cm, 25 cm and 30 cm. Results of study showed that sowing pearl millet into soybean at the intra-row spacing of 30 cm produced the highest pearl millet yields of 4.7 t ha-1 and 4.9 t ha-1 respectively, at Makurdi and Ibi locations, as well as producing the highest soybean yields at both locations. In Makurdi, intercropping pearl millet with soybean significantly (P ≤ 0.05) decreased yield of pearl millet by 32.4 % and that of soybean by 29.4 % compared to sole cropping of the component crops, while at Ibi, intercrop yields of pearl millet and soybean were respectively reduced by 35.9 % and 30.0 % compared to their sole yields. Sowing pearl millet into soybean at the intra-row spacing of 30 cm also gave the highest total intercrop yields, highest land equivalent coefficient (LEC) values, highest land equivalent ratio (LER) values of 2.97 and 2.71 and highest percentage (%) land saved (66.3 % and 63.1 % respectively, recorded at Makurdi and Ibi locations). The implication of study showed that it is most advantageous having both crops in intercrop when pearl millet was sown into soybean at the intra-row spacing of 30 cm. This should therefore, be recommended for the southern guinea savanna, Nigeria.
Źródło:
World Scientific News; 2016, 44; 78-99
2392-2192
Pojawia się w:
World Scientific News
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Efficient FPGA Implementation of Recursive Least Square Adaptive Filter Using Non-Restoring Division Algorithm
Autorzy:
Thannoon, Harith H.
Hashim, Ivan A.
Powiązania:
https://bibliotekanauki.pl/articles/27311979.pdf
Data publikacji:
2023
Wydawca:
Polska Akademia Nauk. Czasopisma i Monografie PAN
Tematy:
Adaptive filter
RLS
AP
CORDIC
non-restoring
Opis:
In this paper, Recursive Least Square (RLS) and Affine Projection (AP) adaptive filters are designed using Xilinx System Generator and implemented on the Spartan6 xc6slx16- 2csg324 FPGA platform. FPGA platform utilizes the non-restoring division algorithm and the COordinate Rotation DIgital Computer (CORDIC) division algorithm to perform the division task of the RLS and AP adaptive filters. The Non-restoring division algorithm demonstrates efficient performance in terms of convergence speed and signal-to-noise ratio. In contrast, the CORDIC division algorithm requires 31 cycles for division initialization, whereas the non-restoring algorithm initializes division in just one cycle. To validate the effectiveness of the proposed filters, a set of ten ECG records from the BIT-MIT database is used to test their ability to remove Power Line Interference (PLI) noise from the ECG signal. The proposed adaptive filters are compared with various adaptive algorithms in terms of Signal-to-Noise Ratio (SNR), convergence speed, residual noise, steady-state Mean Square Error (MSE), and complexity.
Źródło:
International Journal of Electronics and Telecommunications; 2023, 69, 4; 811--817
2300-1933
Pojawia się w:
International Journal of Electronics and Telecommunications
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Enhancing Responsivity of Porous GaN Metal-Semiconductor-Metal Ultraviolet Photodiodes by Using Photoelectrochemical Etching
Autorzy:
Al-Heuseen, K.
Hashim, M.
Powiązania:
https://bibliotekanauki.pl/articles/1490759.pdf
Data publikacji:
2012-01
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
78.67.Rb
42.79.Pw
Opis:
In this paper porous and as-grown GaN metal-semiconductor-metal photodiodes with Ni contact electrodes were fabricated. Structural and optical properties were studied of the both samples. Both detectors show a sharp cut-off wavelength at 370 nm, with a maximum responsivity of 0.14 A/W and 0.065 A/W achieved at 360 nm for porous GaN and as-grown metal-semiconductor-metal photodetectors, respectively. The metal-semiconductor-metal photodiode based on porous GaN shows enhanced twice magnitude of responsivity relative to the as-grown GaN metal-semiconductor-metal photodiode. Enhancement of responsivity can be attributed to the relaxation of stress and reduction of surface pit density in the porous sample. The porous sample showed a significantly low dark current at 5 V as compared to as grown sample.
Źródło:
Acta Physica Polonica A; 2012, 121, 1; 71-73
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Evaluation of Rainfall-Runoff Erosivity Factor for Cameron Highlands, Pahang, Malaysia
Autorzy:
Abdulkadir, T. S.
Mustafa, M. R.
Yusof, K. W.
Hashim, A. M.
Powiązania:
https://bibliotekanauki.pl/articles/123050.pdf
Data publikacji:
2016
Wydawca:
Polskie Towarzystwo Inżynierii Ekologicznej
Tematy:
rainfall
erosivity factor
soil erosion
USLE/RUSLE
runoff
Opis:
Rainfall-runoff is the active agent of soil erosion which often resulted in land degradation and water quality deterioration. Its aggressiveness to induce erosion is usually termed as rainfall erosivity index or factor (R). R-factor is one of the factors to be parameterized in the evaluation of soil loss using the Universal Soil Loss Equation and its reversed versions (USLE/RUSLE). The computation of accurate R-factor for a particular watershed requires high temporal resolution rainfall (pluviograph) data with less than 30-minutes intensities for at least 20 yrs, which is available only in a few regions of the world. As a result, various simplified models have been proposed by researchers to evaluate R-factor using readily available daily, monthly or annual precipitation data. This study is thus aimed at estimating R-factor and to establish an approximate relationship between R-factor and rainfall for subsequent usage in the estimation of soil loss in Cameron highlands watershed. The results of the analysis showed that the least and peak (critical) R-factors occurred in the months of January and April with 660.82 and 2399.18 MJ mm ha-1 h-1year-1 respectively. Also, it was observed that erosivity power starts to increase from the month of January through April before started falling in the month of July. The monthly and annual peaks (critical periods) may be attributed to increased rainfall amount due to climate change which in turn resulted to increased aggressiveness of rains to cause erosion in the study area. The correlation coefficient of 0.985 showed that there was a strong relationship rainfall and R-factor.
Źródło:
Journal of Ecological Engineering; 2016, 17, 3; 1-8
2299-8993
Pojawia się w:
Journal of Ecological Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Experimental Study of Failure Analysis in Notched and Repaired Fiberglass Epoxy Composite
Autorzy:
Hassoon, Omar Hashim
Enzi, Abass
Kashkool, Lujain H.
Powiązania:
https://bibliotekanauki.pl/articles/2172353.pdf
Data publikacji:
2022
Wydawca:
Stowarzyszenie Inżynierów i Techników Mechaników Polskich
Tematy:
damage analysis
GFRP
repaired GFRP
finite element analysis
FEA
Opis:
The composite materials are remarkably increasing in many industry sectors like aircraft, automobiles, oil pipes, and marine boats. This attention comes from their excellent properties, such as lightweight and high strength. However, these materials expose many damages like fiber-matrix debonding, matrix crack, and delamination. The composite structures risked damage through the service life and therefore need to repair to achieve their function with a good performance. This paper focuses on the analysis during the tensile test of samples of fiberglass epoxy composite materials exposed to damage before and after repair. Experimental and numerical investigations are performed to determine and identify mechanical properties and failure analysis between repaired and unrepaired composite plates. Five samples are selected: without hole, 4 mm hole-repaired, stepped hole from 4 to 8 mm, and stepped hole from 4 to 8 mm-repaired. Simulation models are created using the finite element (FE) method to compare them with Abaqus's practical experiments to predict damage during the tensile test. To simulate damage models, interlaminar and intralaminar damage, were used to study initiation and propagation of the samples failure. Results show that the experimental and numerical investigations of the repaired samples have a significant effect on the mechanical properties and failure behavior of the holed and stepped plates compared with unrepaired samples. Also, maximum stress and strain are concentrated around and on both sides of the hole, while the most significant damage occurs around the hole and the axial direction.
Źródło:
Advances in Science and Technology. Research Journal; 2022, 16, 2; 99--108
2299-8624
Pojawia się w:
Advances in Science and Technology. Research Journal
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Factors influencing the transformation of Iraqi holy cities: the case of Al-Najaf
Autorzy:
Farhan, Sabeeh L.
Antón, Daniel
Akef, Venus S.
Zubaidi, Salah L.
Hashim, Khalid S.
Powiązania:
https://bibliotekanauki.pl/articles/35535689.pdf
Data publikacji:
2021
Wydawca:
Szkoła Główna Gospodarstwa Wiejskiego w Warszawie. Wydawnictwo Szkoły Głównej Gospodarstwa Wiejskiego w Warszawie
Tematy:
urban transformation factor
traditional urban pattern
heritage
Al-Najaf
Iraqi holy cities
Islamic culture
Opis:
The historic centre of the Iraqi city of Al-Najaf embraces a seasonal pilgrimage to its holy sites that forces unusual urban conditions. This paper examines the impact of development projects and studies on the heritage integrity of the public (religious). This paper, therefore, recommends raising public awareness to adopt design approaches to face the overflow of visitors and the loss of heritage identity.
Źródło:
Scientific Review Engineering and Environmental Sciences; 2021, 30, 2; 365-375
1732-9353
Pojawia się w:
Scientific Review Engineering and Environmental Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Wyświetlanie 1-15 z 41

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