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Tytuł:
Antifungal activity of sodium chloride on Saprolegnia diclina and Aphanomyces sp.
Autorzy:
Ali, E H
Powiązania:
https://bibliotekanauki.pl/articles/67745.pdf
Data publikacji:
2009
Wydawca:
Polskie Towarzystwo Botaniczne
Tematy:
antifungal activity
sodium chloride
Saprolegnia diclina
Aphanomyces
zoosporic fungi
fungi
salinity
morphogenesis
biochemical activity
sporulation
Opis:
Sixteen identified and three unidentified species belonging to six genera of zoosporic fungi were isolated from forty water samples which were collected from different fish and fish hatcheries farms at Abbassa city, Sharkiya governorate, Egypt, using sesame seeds baiting technique at 20±2°C. Saprolegnia and Achlya contributed the broadest spectra of species diversity amongst the other genera of zoosporic fungi. Saprolegnia diclina and Aphanomyces sp. were the most prevalent species of zoosporic fungi. The abundance of zoosporic fungal species in these aquacultures was correlated with some physicochemical characteristics of the water samples. The two dominant species of zoosporic fungi were tested for their tolerance of NaCl solution and its impact on some morphological and metabolic activities of these fungi. Saprolegnia diclina tolerated concentrations of NaCl solution till 12000 μg/ml whereas the maximum resistance of Aphanomyces sp. was 8000 μg/ml. The examined morphological aspects of the two studied fungal species, which included the colony diameters, the vegetative hyphae, zoosporogenesis, zoospores discharge, sexual reproductive structures and gemmae formation, were generally affected depending upon the tested fungal species and the applied dose of NaCl solution. The low treatments of NaCl solution were significantly stimulative compared with the control for protease production by S. diclina but higher doses were significantly suppressive. A significant decline in protease activity at all applications was found when Aphanomyces sp. was treated with NaCl solution. The total free amino acids and total protein content of S. diclina and Aphanomyces sp. mycelia were almost significantly increased relative to untreated controls at the low dose of NaCl solution and they were significantly dropped at the higher concentrations by the two zoosporic fungi.
Źródło:
Acta Mycologica; 2009, 44, 1; 125-138
0001-625X
2353-074X
Pojawia się w:
Acta Mycologica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Biodiversity of zoosporic fungi in polluted water drainages across Niles Delta region, Lower Egypt
Autorzy:
Ali, E.H.
Powiązania:
https://bibliotekanauki.pl/articles/67773.pdf
Data publikacji:
2007
Wydawca:
Polskie Towarzystwo Botaniczne
Tematy:
biodiversity
zoosporic fungi
fungi
polluted water
water pollution
drainage
Nile River
Lower Egypt
Egypt
Nile Delta
Opis:
Thirty-four identified in addition to five unidentified species appertaining to ten genera of zoosporic fungi were identified and isolated from eighty four polluted water samples, which were randomly collected from different polluted sites of the water drainages along the Niles Delta in Lower Egypt. Baiting sesame seeds culture technique was employed at 20±2°C for the recovery of zoosporic fungi. The genera; Pythium and Saprolegnia (8 and 7 zoosporic fungal species, respectively) showed the broadest spectra of species diversity whereas Aqualinderella was only represented by one species (A. fermentans). Saprolegnia delica and Dictyuchus carpophorus(the greatest fungal populations) were the most dominant isolated zoosporic fungal species where they were highly occurred especially at the hyperpolluted waters with the heavy metals. These two species could be considered as indicators for the response of the structure and function of microbial communities for water pollution. Several zoosporic fungal species were rarely encountered. Both Aqualinderella fermentansand Pythium rostratumwere recovered in moderate frequency of occurrence. Water samples which had high concentrations in heavy metals were the poorest in the species diversity of zoosporic fungi. Despite that, fungal species belonging to the family Saprolegniaceaeflourished in hyper polluted water samples whilst those belonging to the family Pythiaceae predominated in more diluted water samples. Also, the prevalent species; S. delica andD. carpophoruswere not affected by heavy metals concentrations being as indicators for water pollution with the heavy metals. pH values of the polluted water samples had no influence on the occurrence of zoosporic fungi. Water samples characterized by high organic matter content and low total soluble salts were the richest in zoosporic fungal species.
Źródło:
Acta Mycologica; 2007, 42, 1
0001-625X
2353-074X
Pojawia się w:
Acta Mycologica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Energy efficiency analysis of styrene production by adiabatic ethylbenzene dehydrogenation using exergy analysis and heat integration
Autorzy:
Ali, E.
Hadj-Kali, M.
Powiązania:
https://bibliotekanauki.pl/articles/949461.pdf
Data publikacji:
2018
Wydawca:
Zachodniopomorski Uniwersytet Technologiczny w Szczecinie. Wydawnictwo Uczelniane ZUT w Szczecinie
Tematy:
Styrene production
Ethylbenzene dehydrogenation
Exergy analysis
Heat Integration
Pinch Analysis
Heat Recovery
Opis:
Styrene is a valuable commodity for polymer industries. The main route for producing styrene by dehydrogenation of ethylbenzene consumes a substantial amount of energy because of the use of high-temperature steam. In this work, the process energy requirements and recovery are studied using Exergy analysis and Heat Integration (HI) based on Pinch design method. The amount of steam plays a key role in the trade-off between Styrene yield and energy savings. Therefore, optimizing the operating conditions for energy reduction is infeasible. Heat integration indicated an insignificant reduction in the net energy demand and exergy losses, but 24% and 34% saving in external heating and cooling duties, respectively. When the required steam is generated by recovering the heat of the hot reactor effluent, a considerable saving in the net energy demand, as well as the heating and cooling utilities, can be achieved. Moreover, around 68% reduction in the exergy destruction is observed.
Źródło:
Polish Journal of Chemical Technology; 2018, 20, 1; 35-46
1509-8117
1899-4741
Pojawia się w:
Polish Journal of Chemical Technology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Involvement of ethylene synthetic inhibitors in regulating the senescence of cut carnations through membrane integrity maintenance
Autorzy:
Hassan, F.
Ali, E.
Mazrou, R.
Powiązania:
https://bibliotekanauki.pl/articles/1079037.pdf
Data publikacji:
2020
Wydawca:
Instytut Ogrodnictwa
Tematy:
cut flower
flower senescence
1-methylcyclopropene
silver nanoparticle
nitric oxide
sodium nitroprusside
vase life
membrane stability
cut carnation
Opis:
Postharvest senescence is a critical problem of carnation cut flowers, limiting their transportation and subsequent marketing chain. This study was designed to assess whether the application of 1-methylcyclopropene (1 MCP), silver nanoparticles (AgNPs), and nitric oxide (NO) released from donor sodium nitroprusside (SNP) could prolong the vase life of cut carnations through an influence on the physiological and biochemical mechanisms involved in aging process. 1-MCP was used in the concentrations of 0, 100, 200, and 300 mg·m-3; AgNPs in the concentrations of 0, 50, 100, and 150 mg·dm-3; and SNP in the concentrations of 0, 0.1, 0.2, 0.3, and 0.4 mM. All treatments significantly extended the cut flower life compared with untreated flowers, more so with 300 mg·m-3 of 1-MCP, 100 mg·dm-3 of AgNPs, or 0.3 mM of SNP. All these chemical compounds were able to considerably improve the relative water content (RWC), reduce the malondialdehyde (MDA) content and increase the membrane stability index (MSI) in petals and, therefore, maintain the membrane integrity. In addition, they decreased the activities of acetyl-CoA synthetase (ACS) and nitric oxide synthase (NOS) and, hence, depressed the production of ethylene in carnation cut flowers through downregulating the ethylene production, what prolonged the vase life. Altogether, the application of exogenous 1-MCP, AgNPs, or SNP may provide a promising avenue to improve the postharvest performance of carnation cut flowers.
Źródło:
Journal of Horticultural Research; 2020, 28, 1; 39-48
2300-5009
Pojawia się w:
Journal of Horticultural Research
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Linkage of two mutant allozymes for Amp2 and Aat2 with marker loci on barley [Hordeum vulgare L.] chromosomes 1 and 6
Autorzy:
Kucharska, M
Kaczorowska, K.
Ali, E.S.
Powiązania:
https://bibliotekanauki.pl/articles/2048291.pdf
Data publikacji:
1998
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
chromosome
starch
isoenzyme
barley
linkage
gel electrophoresis
mutant
allozyme
genetic analysis
Hordeum vulgare
genetic marker
Opis:
To saturate barley (Hordeum vulgare L.) genetic maps the linkage relationships of two isoenzyme loci Amp2 (aminopeptydase) and Aat2 (aspartate aminotransferase) with known genetic markers were investigated. Results of the genetic analysis support previous information on the localization of these loci on chromosome 1 and 6, respectively. The following recombination values were estimated: between locus Amp2 and T1-3b translocation break point 13.8 ± 2.1%, between locus Aat2 and translocation T6-7i, 17 ± 3.0% and between locus Aat2 and marker о 24.1 ± 3.0%.
Źródło:
Journal of Applied Genetics; 1998, 39, 2; 147-150
1234-1983
Pojawia się w:
Journal of Applied Genetics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Supplemental effects of silicon nutrition on growth, quality and some physiological characters of potted chrysanthemum grown in greenhouse
Suplementacyjny wpływ żywienia krzemem na wzrost, jakość i niektóre cechy fizjologiczne doniczkowych chryzantem uprawianych w szklarni
Autorzy:
Ali, E.F.
Hassan, F.A.S.
Powiązania:
https://bibliotekanauki.pl/articles/11543323.pdf
Data publikacji:
2016
Wydawca:
Uniwersytet Przyrodniczy w Lublinie. Wydawnictwo Uniwersytetu Przyrodniczego w Lublinie
Tematy:
supplementation effect
silicon
membrane stability
plant growth
plant quality
plant physiology
pot chrysanthemum
chrysanthemum
greenhouse
Opis:
Potted chrysanthemum is one of the most important floriculture plants which commercially produced in greenhouses where silicon (Si) is available in limited concentration because of using several substrates as growing media. Therefore, this study was conducted to investigate the supplemental effects of Si nutrition on growth, flowering, flower longevity as well as shelf life and nutrients content of potted chrysanthemum in relation to Si application. Moreover, the effects of Si treatment on some physiological parameters i.e. chlorophyll content, stomatal resistance, membrane stability index (MSI) and total carbohydrates were also investigated. Si application as K₂SiO₃ was added whether as foliar application at 25, 75 and 125 mg L⁻¹ Si or soil drenches at 50, 100 and 150 mg L⁻¹ Si. Except plant height and leaf area, the other vegetative growth and flowering characters were improved as a result of both Si supplementation methods compared with untreated control. Flowering was earlier and shelf life was longer in Si-supplemented than nonsupplemented plants. Generally, Si application increased the macro and micronutrients concentrations (except Ca) estimated in this study. Chlorophyll content, stomatal resistance, MSI and total carbohydrates were increased among Si treated plants. Improving the floricultural traits, extending longevity and shelf life of greenhouse grown chrysanthemum may give an impact of its greenhouse commercial production if appropriate level was used.
Chryzantema doniczkowa to jedna z najważniejszych roślin, które są komercyjnie produkowane w szklarniach, gdzie krzem (Si) jest dostępny w ograniczonym stężeniu, gdyż do uprawy używane są różne podłoża. Niniejsze badanie przeprowadzono w celu zbadania skutków suplementacyjnych żywienia Si na wzrost, kwitnienie, długość życia kwiatów, a także żywotność i zawartość składników odżywczych chryzantemy doniczkowej w stosunku do aplikacji Si. Ponadto zbadano skutki zabiegów z użyciem Si na niektóre parametry fizjologiczne, to znaczy zawartość chlorofilu, działanie aparatów szparkowych, wskaźnik stabilności błon (MSI) oraz całkowitą zawartość węglowodanów. Zastosowanie Si w postaci K₂SiO₃ dodano jako aplikację dolistną w ilości 25, 75 i 125 mg L⁻¹ Si lub do podłoża przy 50, 100 i 150 mg L⁻¹ Si. Z wyjątkiem wysokości roślin i obszaru liścia, w porównaniu z kontrolą bez żadnych zabiegów, wszystkie cechy wzrostu i kwitnienia polepszyły się w wyniku zastosowania obu metod suplementacji. Kwitnienie było wcześniejsze, a żywotność dłuższa u roślin z suplementacją Si niż u roślinach bez suplementacji. Generalnie zastosowanie Si zwiększało stężenie makro- i mikroskładników (z wyjątkiem Ca) ocenianych w niniejszym badaniu. Zawartość chlorofilu, działanie aparatów szparkowych, MSI oraz całkowita zawartość węglowodanów zwiększały się wśród roślin z zastosowaniem Si. Polepszenie cech kwiatowych, zwiększenie długości życia i żywotności chryzantem hodowanych w szklarni może mieć wpływ na komercyjną produkcję szklarniową, jeśli zastosuje się jego odpowiedni poziom.
Źródło:
Acta Scientiarum Polonorum. Hortorum Cultus; 2016, 15, 4; 85-98
1644-0692
Pojawia się w:
Acta Scientiarum Polonorum. Hortorum Cultus
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Beam Pattern Optimization Via Unequal Ascending Clusters
Autorzy:
Abdulqader, Ahmed Jameel
Mohammed, Jafar Ramadhan
Ali, Yessar E. Mohammad
Powiązania:
https://bibliotekanauki.pl/articles/2200966.pdf
Data publikacji:
2023
Wydawca:
Instytut Łączności - Państwowy Instytut Badawczy
Tematy:
beam pattern
clustered array
genetic algorithm
sidelobes
Opis:
In this paper, two different architectures based on completely and sectionally clustered arrays are proposed to improve the array patterns. In the wholly clustered arrays, all elements of the ordinary array are divided into multiple unequal ascending clusters. In the sectionally clustered arrays, two types of architectures are proposed by dividing a part of the array into clusters based on the position of specific elements. In the first architecture of sectionally clustered arrays, only those elements that are located on the sides of the array are grouped into unequal ascending clusters, and other elements located in the center are left as individual and unoptimized items (i.e. uniform excitation). In the second architecture, only some of the elements close the center are grouped into unequal ascending clusters, and the side elements were left individually and without optimization. The research proves that the sectionally clustered architecture has many advantages compared to the completely clustered structure, in terms of the complexity of the solution. Simulation results show that PSLL in the side clustered array can be reduced to more than −28 dB for an array of 40 elements. The PSLL was −17 dB in the case of a centrally clustered array, whereas the complexity percentage in the wholly clustered array method was 12 .5 %, while the same parameter for the partially clustered array method equaled 10%.
Źródło:
Journal of Telecommunications and Information Technology; 2023, 1; 1--7
1509-4553
1899-8852
Pojawia się w:
Journal of Telecommunications and Information Technology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
On a regularization method for variational inequalities with P0 mappings
Autorzy:
Konnov, I.
Mazurkevich, E.
Ali, M.
Powiązania:
https://bibliotekanauki.pl/articles/908486.pdf
Data publikacji:
2005
Wydawca:
Uniwersytet Zielonogórski. Oficyna Wydawnicza
Tematy:
nierówność wariacyjna
metoda regularyzacji
variational inequalitie
partial regularization approach
P0-mappings
Opis:
We consider partial Browder-Tikhonov regularization techniques for variational inequality problems with P0 cost mappings and box-constrained feasible sets. We present classes of economic equilibrium problems which satisfy such assumptions and propose a regularization method for these problems.
Źródło:
International Journal of Applied Mathematics and Computer Science; 2005, 15, 1; 35-44
1641-876X
2083-8492
Pojawia się w:
International Journal of Applied Mathematics and Computer Science
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Total vertex irregularity strength of disjoint union of Helm graphs
Autorzy:
Ahmad, Ali
Baskoro, E.
Imran, M.
Powiązania:
https://bibliotekanauki.pl/articles/743230.pdf
Data publikacji:
2012
Wydawca:
Uniwersytet Zielonogórski. Wydział Matematyki, Informatyki i Ekonometrii
Tematy:
vertex irregular total k-labeling
Helm graphs
total vertex irregularity strength
Opis:
A total vertex irregular k-labeling φ of a graph G is a labeling of the vertices and edges of G with labels from the set {1,2,...,k} in such a way that for any two different vertices x and y their weights wt(x) and wt(y) are distinct. Here, the weight of a vertex x in G is the sum of the label of x and the labels of all edges incident with the vertex x. The minimum k for which the graph G has a vertex irregular total k-labeling is called the total vertex irregularity strength of G. We have determined an exact value of the total vertex irregularity strength of disjoint union of Helm graphs.
Źródło:
Discussiones Mathematicae Graph Theory; 2012, 32, 3; 427-434
2083-5892
Pojawia się w:
Discussiones Mathematicae Graph Theory
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
On bi-criteria two-stage transportation problem: a case study
O dwukryterialnym, dwuetapowym problemie transportowym: studium przypadku
Autorzy:
Murad, A.
Al-Ali, A.
Ellaimony, E.
Abdelwali, H.
Powiązania:
https://bibliotekanauki.pl/articles/374839.pdf
Data publikacji:
2010
Wydawca:
Politechnika Śląska. Wydawnictwo Politechniki Śląskiej
Tematy:
problem transportowy dwuetapowy
problem transportowy dwukryterialny
two stage transportation problem
bi-criteria transportation problem
Opis:
The study of the optimum distribution of goods between sources and destinations is one of the important topics in projects economics. This importance comes as a result of minimizing the transportation cost, deterioration, time, etc. The classical transportation problem constitutes one of the major areas of application for linear programming. The aim of this problem is to obtain the optimum distribution of goods from different sources to different destinations which minimizes the total transportation cost. From the practical point of view, the transportation problems may differ from the classical form. It may contain one or more objective function, one or more stage to transport, one or more type of commodity with one or more means of transport. The aim of this paper is to construct an optimization model for transportation problem for one of mill-stones companies. The model is formulated as a bi-criteria two-stage transportation problem with a special structure depending on the capacities of suppliers, warehouses and requirements of the destinations. A solution algorithm is introduced to solve this class of bi-criteria two-stage transportation problem to obtain the set of non-dominated extreme points and the efficient solutions accompanied with each one that enables the decision maker to choose the best one. The solution algorithm mainly based on the fruitful application of the methods for treating transportation problems, theory of duality of linear programming and the methods of solving bi-criteria linear programming problems.
Analiza optymalnej dystrybucji towarów pomiędzy punktem początkowym a końcowym jest jednym z ważnych zagadnień w ekonomice projektów. Ma to znaczenie jako wynik minimalizacji kosztów transportu, rozkładu przewozów, czasu, etc. Klasyczny problem transportowy stanowi jedno z głównych zagadnień programowania liniowego. Rozwiązaniem tego problemu jest uzyskanie optymalnej dystrybucji towarów z różnych źródeł do różnych punktów przeznaczenia, co minimalizuje całkowity koszt transportu. Z praktycznego punktu widzenia problemy transportowe mogą się różnić od problemów w formie klasycznej. Mogą one zawierać jedną lub więcej funkcji celu, jedną lub więcej tras, jeden lub więcej rodzajów towarów przewożonych za pomocą jednego lub więcej środków transportu. Celem artykułu jest stworzenie modelu optymalizacyjnego, który rozwiązuje problem transportowy dla jednej z firm przewozowych, specjalizującej się w przewozie kruszyw. Model jest sformułowany jako dwukryterialny, dwuetapowy problem transportowy w celu pozyskania zbioru ekstremów lokalnych oraz skutecznych rozwiązań związanych z takimi, które pozwalają osobie podejmującej decyzję wybrać te najodpowiedniejsze. Algorytm rozwiązania bazuje głównie na efektywnej aplikacji metod rozwiązywania problemów transportowych, teorii dualizmu programowania liniowego oraz metodach poszukiwania rozwiązań dwukryterialnych problemów programowania liniowego.
Źródło:
Transport Problems; 2010, 5, 3; 103-114
1896-0596
2300-861X
Pojawia się w:
Transport Problems
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
An Approach to Design Broadband Air Backed Piezoelectric Sensor
Autorzy:
Ali, M. G. S.
Elsayed, N. Z.
Eid, E. A.
Powiązania:
https://bibliotekanauki.pl/articles/176360.pdf
Data publikacji:
2015
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
piezoelectric
equivalent circuits
impulse response
frequency response
matching layers
z-transform
Opis:
In this work, an approach to the design of broadband thickness-mode piezoelectric transducer is presented. In this approach, simulation of discrete time model of the impulse response of matched and backed piezoelectric transducer is used to design high sensitivity, broad bandwidth, and short-duration impulse response transducers. The effect of matching the performance of transmitting and receiving air backed PZT-5A transducer working into water load is studied. The optimum acoustical characteristics of the quarter wavelength matching layers are determined by a compromise between sensitivity and pulse duration. The thickness of bonding layers is smaller than that of the quarter wavelength matching layers so that they do not change the resonance peak significantly. Our calculations show that the −3 dB air backed transducer bandwidth can be improved considerably by using quarter wavelength matching layers. The computer model developed in this work to predict the behavior of multilayer structures driven by a transient waveform agrees well with measured results. Furthermore, the advantage of this this model over other approaches is that the time signal for optimum set of matching layers can be predicted rapidly.
Źródło:
Archives of Acoustics; 2015, 40, 1; 3-10
0137-5075
Pojawia się w:
Archives of Acoustics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A Simulation for Detecting Nonlinear Echoes from Microbubbles Packets
Autorzy:
Ali, M. G. S.
Elsayed, N. Z.
Eid, E. A.
Powiązania:
https://bibliotekanauki.pl/articles/177697.pdf
Data publikacji:
2015
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
microbubbles packets
harmonic component
acoustic
radial dynamic
pressure spectrum
Opis:
This work presents a simulation of the response of packets of microbubbles in an ultrasonic pulse-echo scan line. Rayleigh-Plesset equation has been used to predict the echo from numerically obtained radial dynamics of microbubbles. Varying the number of scattering microbubbles on the pulse wave form has been discussed. To improve microbubble-specific imaging at high frequencies, the subharmonic and second harmonic signals from individual microbubbles as well as microbubbles packets were simulated as a function of size and pressure. Two different modes of harmonic generation have been distinguished. The strength and bandwidth of the subharmonic component in the scattering spectrum of microbubbles is greater than that of the second harmonic. The pressure spectra provide quantitative and detailed information on the dynamic behaviour of ultrasound contrast agent microbubbles packet.
Źródło:
Archives of Acoustics; 2015, 40, 2; 151-157
0137-5075
Pojawia się w:
Archives of Acoustics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Evaluation of Forecasts Performance of ARIMA-GARCH-type Models in the Light of Outliers
Autorzy:
Akpan, Emmanuel Alphonsus
Lasisi, K. E.
Adamu, Ali
Rann, Haruna Bakari
Powiązania:
https://bibliotekanauki.pl/articles/1075685.pdf
Data publikacji:
2019
Wydawca:
Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Tematy:
ARIMA Model
Forecast
GARCH Model
Heteroscedasticity
Outlier
Volatility
Opis:
The carry-over effect of biased estimates of ARIMA-GARCH-type models parameters on forecasting accuracy is investigated in the presence of outliers by exploring the daily returns of share price series of three major banks in Nigerian. The banks considered are Diamond, United bank for Africa and Union. The data were collected from the Nigerian Stock Exchange and spanned from January 3, 2006 to December 30, 2016, comprises 2713 observations and were divided into two portions. The first portion which ranges from January 3, 2006 to November 24, 2016, comprises 2690 observations was used for model formulation and the second portion which ranges from November 25, 2016 to December 30, 2016, consisting of 23 observations was used for out-of-sample forecasting performance evaluation. The parametric bootstrap technique was used in computing the forecasts while Mean Squared Error (MSE), Root Mean Squared Error (RMSE), Mean Absolute Error (MAE) and Mean Error (ME) were the methods of forecast evaluation considered. The findings of this study showed that in the presence of outliers, the forecasts were found to be biased as indicated by ME and the accuracy reduced as shown by MSE, RMSE and MAE. However, adjusting for the outliers, only marginal improvement on the forecasts was observed, reason being that all the outliers were treated as innovations and they occurred before the forecasts origin.
Źródło:
World Scientific News; 2019, 119; 68-84
2392-2192
Pojawia się w:
World Scientific News
Dostawca treści:
Biblioteka Nauki
Artykuł
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