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Tytuł:
The deployment of performance measurement system under the supply chain management environment: the case of Malaysian manufacturing companies
Autorzy:
Ahmad, K.
Zabri, S. M.
Powiązania:
https://bibliotekanauki.pl/articles/407217.pdf
Data publikacji:
2018
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
performance measures
supply chain management
manufacturing sector
performance
Malaysia
Opis:
Performance measurement system in supply chain management (SCM) has been receiving increasing attention by business organizations as a way to evaluate efficiency in supply chain activities. Assessing the performance of supply chain uncovers the gap between planning and actual performance as to trace the potential problems thus ascertain necessary areas for improvement. This research aims to investigate the application of performance measurement system in SCM as well as exploring its relationship with organization’s performance among Malaysian manufacturing firms. By utilizing the questionnaire method, respondents involved were requested to indicate the extent to which they use a number of 24 selected performance measures that are related to SCM. The results show that the majority of the observed manufacturing firms utilize specific performance measurement tools in evaluating the supply chain performance. The current performance measurement techniques, the Balanced Score Card is adopted by around a quarter of the total responding firms followed by Supply Chain Operations References Model – SCOR, which attracts total users of only a fifth of the total respondents. In particular, performance measures under customer service category recorded the highest number of usage followed by cost-based performance measures and operations management. The results of this investigation also unveil few major points that are important to be highlighted. Firstly, the obtained outcomes of this study bring to light the significant relationships between the utilization of supply chain performance measures under customer service, operations management and organizational performance. In addition, this study discovered a significant correlation between the size of the organization and the extent of use of supply chain performance measures and how these two variables positively correlated. Lastly, the findings also suggested that the performance measures for SCM has been playing a crucial role in enhancing the performance of the organizations and is increasingly operated as the firms grow in size. Based on the brief highlighted points listed above, it is not an exaggeration to say that this research contributes new information to the body of knowledge in performance measurement system in SCM and its associations with organizational performance.
Źródło:
Management and Production Engineering Review; 2018, 9, 1; 3-12
2080-8208
2082-1344
Pojawia się w:
Management and Production Engineering Review
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Limit cycle oscillation prediction based on Finite Element-Modal approach
Autorzy:
Ahmad, K.
Wu, Z.
Rahman, H.
Powiązania:
https://bibliotekanauki.pl/articles/140294.pdf
Data publikacji:
2018
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
geometrical nonlinearity
unsteady aerodynamics
bending mode
torsional mode
aeroelasticity
flexible structure
nieliniowość geometryczna
aerodynamika niestabilna
tryb zginania
tryb skrętny
aeroelastyczność
struktura elastyczna
Opis:
The central theme of this work was to analyze high aspect ratio structure having structural nonlinearity in low subsonic flow and to model nonlinear stiffness by finite element-modal approach. Total stiffness of high aspect ratio wing can be decomposed to linear and nonlinear stiffnesses. Linear stiffness is modeled by its eigenvalues and eigenvectors, while nonlinear stiffness is calculated by the method of combined Finite Element-Modal approach. The nonlinear modal stiffness is calculated by defining nonlinear static load cases first. The nonlinear stiffness in the present work is modeled in two ways, i.e., based on bending modes only and based on bending and torsion modes both. Doublet lattice method (DLM) is used for dynamic analysis which accounts for the dependency of aerodynamic forces and moments on the frequency content of dynamic motion. Minimum state rational fraction approximation (RFA) of the aerodynamic influence coefficient (AIC) matrix is used to formulate full aeroelastic state-space time domain equation. Time domain dynamics analyses show that structure behavior becomes exponentially growing at speed above the flutter speed when linear stiffness is considered, however, Limit Cycle Oscillations (LCO) is observed when linear stiffness along with nonlinear stiffness, modeled by FE-Modal approach is considered. The amplitude of LCO increases with the increase in the speed. This method is based on cantilevered configuration. Nonlinear static tests are generated while wing root chord is fixed in all degrees of freedom and it needs modification if one requires considering full aircraft. It uses dedicated commercial finite element package in conjunction with commercial aeroelastic package making the method very attractive for quick nonlinear aeroelastic analysis. It is the extension of M.Y. Harmin and J.E. Cooper method in which they used the same equations of motion and modeled geometrical nonlinearity in bending modes only. In the current work, geometrical nonlinearities in bending and in torsion modes have been considered.
Źródło:
Archive of Mechanical Engineering; 2018, LXV, 4; 497-514
0004-0738
Pojawia się w:
Archive of Mechanical Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Ethnobotanical investigation of wild vegetables used among local communities in northwest Pakistan
Autorzy:
Ahmad, K.
Weckerle, C.S.
Nazir, A.
Powiązania:
https://bibliotekanauki.pl/articles/57306.pdf
Data publikacji:
2019
Wydawca:
Polskie Towarzystwo Botaniczne
Opis:
Wild vegetables can contribute to people’s food security and health. In northwest Pakistan, almost 40% of the households are classified as food insecure, due to increasing population and natural and man-made catastrophes. There is an urgent need to get an overview of still existing practices of wild vegetable use and to incorporate such knowledge into agricultural policies. The present study, therefore, aims to collect and analyze information on the most widely and commonly used wild vegetables in northwest Pakistan. Semistructured interviews were performed with 126 informants (26–78-year old) from all 24 districts of the Khyber Pakhtunkhwa Province. Information on culinary and medicinal use, cooking methods, and growing and harvest season were collected. A rating scale was used to get the opinion on quality, abundance, and use frequency of wild vegetables. Information on trading was gathered on local and regional markets. Transect walks were done with key informants for specimen collection. A total of 25 wild vegetable species (21 genera, 13 families) were documented. Most of them are herbs (22 spp.). One third of the species needs processing or detoxification prior to cooking. Taste and food quality as perceived by the local people are the main driver for use frequency and commercialization. Length of availability varies from 2 to 7 months with Rumex dentatus and Vicia faba also available during the winter season. Overall, 21 spp. are also used medicinally, mainly for gastrointestinal diseases. Leaves are the preferred plant part for both vegetables and medicines. Nine species are sold in markets, Bauhinia variegata and Caralluma tuberculata throughout the whole province. Local communities in northwest Pakistan have a broad knowledge of local plant use, especially on wild vegetables and their adequate processing. The present study suggests that the most commonly used wild vegetables should be promoted to reinforce food safety and most of them may also be commercialized. Conservation priority has to be given to the commercially harvested Caralluma tuberculata, which is presently overexploited.
Źródło:
Acta Societatis Botanicorum Poloniae; 2019, 88, 1
0001-6977
2083-9480
Pojawia się w:
Acta Societatis Botanicorum Poloniae
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Boundary value problems for n-th order differential inclusions with four-point integral boundary conditions
Autorzy:
Ahmad, B.
Ntouyas, S. K.
Powiązania:
https://bibliotekanauki.pl/articles/255975.pdf
Data publikacji:
2012
Wydawca:
Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH
Tematy:
differential inclusions
four-point integral boundary conditions
existence
nonlinear alternative of Leray Schauder type
fixed-point theorems
Opis:
In this paper, we discuss the existence of solutions for a four-point integral boundary value problem of n-th order differential inclusions involving convex and non-convex multivalued maps. The existence results are obtained by applying the nonlinear alternative of Leray Schauder type and some suitable theorems of fixed point theory.
Źródło:
Opuscula Mathematica; 2012, 32, 2; 205-226
1232-9274
2300-6919
Pojawia się w:
Opuscula Mathematica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Numerical simulation of flow and heat transfer in hydromagnetic micropolar fluid between two stretchable disks with viscous dissipation effects
Autorzy:
Ali, K.
Ahmad, S.
Ashraf, M.
Powiązania:
https://bibliotekanauki.pl/articles/279778.pdf
Data publikacji:
2016
Wydawca:
Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej
Tematy:
MHD
micropolar fluid
stretchable disk
viscous dissipation
couple stress
heat transfer rate
Opis:
A study of magnetohydrodynamic (MHD) flow with viscous dissipation and heat transfer in an electrically conducting laminar steady viscous incompressible micropolar fluid between two infinite uniformly stretching disks is presented. The transformed self similar nonlinear ODEs are first linearized using a quasi linearization method and then solved by employing a combination of a direct and an iterative method. The study may be beneficial to flow and thermal control of polymeric processing.
Źródło:
Journal of Theoretical and Applied Mechanics; 2016, 54, 2; 633-643
1429-2955
Pojawia się w:
Journal of Theoretical and Applied Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Revitalization and preservation of biodiversity. Focus on water bodies in the Cracow region
Autorzy:
Wagner, Aleksandra
Gholami, Ahmad
Maletz, Katharina
Talmo, Ina K.
Powiązania:
https://bibliotekanauki.pl/articles/2064416.pdf
Data publikacji:
2019
Wydawca:
STE GROUP
Tematy:
pond
revitalization
birds
biodiversity loss
staw
akwen wodny
rewitalizacja
ptaki
różnorodność biologiczna
Opis:
The studies included 2 water bodies in Cracow (Kraków), 6 water bodies in the commune of Zabierzów (Cracow County) and 4 in the commune of Niepołomice (Wieliczka County). The studies were carried out in June 2018 and May 2019. The ways on management of the water bodies were compared. Problems related to revitalization were identified. One of these problems is the preservation of biodiversity. In some cases revitalization reduces biodiversity. This can happen due to the liquidation or limitation of the reed bed zone. Such a situation was observed in the water bodied of Zelków and Karniowice (com. Zabierzów). Both have ornamental functions now. Removal of most of reed does not disturb mallards (Anas platyrhynchos), but makes it impossible to nest for other birds such as moorhen (Galinula chloropus). Moorhens were observed in two former fish ponds in Staniątki (com. Niepołomice) and in the pond of the Kaczeńcowa street. In one of them revitalization caused the diminishing of the water area, but did not change the character of the water body. Bird species were recorded at water bodies.
Źródło:
New Trends in Production Engineering; 2019, 2, 1; 496--504
2545-2843
Pojawia się w:
New Trends in Production Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Prediction of protein subcellular localization using support vector machine with the choice of proper kernel
Autorzy:
Hasan, M.A.M.
Ahmad, S.
Molla, M.K.I.
Powiązania:
https://bibliotekanauki.pl/articles/81150.pdf
Data publikacji:
2017
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
subcellular localization
protein
prediction
support vector machine
model selection
kernel
radial base function
Źródło:
BioTechnologia. Journal of Biotechnology Computational Biology and Bionanotechnology; 2017, 98, 2
0860-7796
Pojawia się w:
BioTechnologia. Journal of Biotechnology Computational Biology and Bionanotechnology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Foliar application of salicylic acid with salinity stress on physiological and biochemical attributes of sunflower (Helianthus annuus L.) crop
Autorzy:
Noreen, S.
Siddiq, A.
Hussain, K.
Ahmad, S.
Hasanuzzama, M.
Powiązania:
https://bibliotekanauki.pl/articles/11543526.pdf
Data publikacji:
2017
Wydawca:
Uniwersytet Przyrodniczy w Lublinie. Wydawnictwo Uniwersytetu Przyrodniczego w Lublinie
Opis:
The potential agricultural lands are falling prey to salinity in the world over including Pakistan. The limited water supply is also becoming a serious problem to feed the humans and livestock production. Therefore, research studies were undertaken to enhance the growth and development of sunflower (Helianthus annuus L.) on saline soils to increase productively of crop. The treatments consisted of (a) two lines of sunflower (Hysun-33 and LG-56-63), (b) two levels of salinity (0, 120 mM (NaCl)) and (c) two levels of salicylic acid (0, 200 mg L-1) and were arranged in a completely randomized design with four replications. The results showed that biological yield was significantly reduced due to imposition of salinity at the rate of 120 mM (NaCl) on both sunflower lines (Hysun -33, LG 56-63). The stem length was also reduced due to decrease in biological yield in response to salinity. However, the exogenous application of salicylic acid at the rate of 200 mg L-1 mitigated the adverse effects of salts and improved the biological yield and stem length under saline and non-saline environments. The quantity of chlorophyll (SPAD) values were impacted negatively in response to salt stress, however, the phenomenon was recovered by foliar spray of salicylic acid. The nutrient concentration of K+, Cl- and Na+ were altered because of presence of excess quantity of NaCl in the substrate. The translocation of K+ ion was reduced substantially, while higher amount of Na+ and Cl- ions were absorbed, thus creating ionic imbalance in the plant system. The foliar spray of salicylic acid (200 mg L-1) enhanced the uptake of K+ from the soil medium. The salicylic acid proved a potential phytoprotectant to mitigate the adverse effects of salinity and thereby improving the physiological and biochemicals attributes, stem length and also enhanced uptake of K+ ion while depressing Na+ and Cl- ions in plant system.
Źródło:
Acta Scientiarum Polonorum. Hortorum Cultus; 2017, 16, 2; 57-74
1644-0692
Pojawia się w:
Acta Scientiarum Polonorum. Hortorum Cultus
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Mechanical Behaviour of Hybrid Composites Developed from Textile Waste
Ocena właściwości mechanicznych kompozytów hybrydowych wytworzonych z odpadów włókienniczych
Autorzy:
Masood, Z.
Ahmad, S.
Umair, M.
Shaker, K.
Nawab, Y.
Karahan, M.
Powiązania:
https://bibliotekanauki.pl/articles/231976.pdf
Data publikacji:
2018
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Biopolimerów i Włókien Chemicznych
Tematy:
hybrid composite
textile waste
dynamic mechanical analysis
mechanical properties
kompozyt hybrydowy
odpady włókiennicze
dynamiczna analiza mechaniczna
właściwości mechaniczne
Opis:
The current study focused on the use of textile industry waste (cotton and jute) and glass fabric for the development of hybrid composites. Composites were fabricated using either a single reinforcement or different fractions of cotton, jute and glass fabric. A good fibre-matrix interface was observed using Scanning Electronic Microscopy (SEM). The mechanical performance of the composites developed was analysed under certain loads. The tensile and flexural properties of the composites developed from waste material was found lower as compared to the glass fiber composites, while hybrid composites had comparable properties. Regression equations were also developed to predict the mechanical properties of the hybrid composites. Dynamic Mechanical Analysis (DMA) results revealed that after some pre-treatment (mercerization and desizing) textile waste materials can be used with virgin material in the reinforcement part of the composite to decrease the cost, but with optimum mechanical properties.
Przeprowadzone badania koncentrowały się na wykorzystaniu odpadów włókienniczych (bawełna i juta) oraz wyrobów z włókien szklanych do rozwoju kompozytów hybrydowych. Otrzymane kompozyty poddano ocenie przy użyciu skaningowej mikroskopii elektronowej (SEM), a także zbadano ich właściwości mechaniczne. Wytrzymałość na rozciąganie i zginanie kompozytów wytworzonych z materiału odpadowego były niższe w porównaniu z kompozytami z włókna szklanego, podczas gdy kompozyty hybrydowe miały porównywalne właściwości. W celu przewidywania właściwości mechanicznych kompozytów hybrydowych opracowano równania regresji. Wyniki dynamicznej analizy mechanicznej (DMA) wykazały, że po pewnym wstępnym przygotowaniu (merceryzacja i usuwanie klejonki) odpady włókiennicze mogą być z powodzeniem stosowane w połączeniu z nieużywanym materiałem w części wzmacniającej kompozytu, przyczyniając się do zmniejszenia kosztów produkcji, przy zachowaniu optymalnych właściwości mechanicznych kompozytów. Wytwarzanie kompozytów hybrydowych może śmiało przyczynić się do rozwiązania problemów związanych z usuwaniem odpadów tekstylnych.
Źródło:
Fibres & Textiles in Eastern Europe; 2018, 1 (127); 46-52
1230-3666
2300-7354
Pojawia się w:
Fibres & Textiles in Eastern Europe
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Impact of family-based selection on growth performance and immune response of Japanese quail
Autorzy:
Rehman, A.
Hussain, J.
Mahmud, A.
Javed, K.
Ghayas, A.
Ahmad, S.
Powiązania:
https://bibliotekanauki.pl/articles/2087135.pdf
Data publikacji:
2021
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
weight base selection
egg base selection
growth performance
immune response
Źródło:
Polish Journal of Veterinary Sciences; 2021, 24, 4; 479-486
1505-1773
Pojawia się w:
Polish Journal of Veterinary Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Hyperelastic models for the description and simulation of rubber subjected to large tensile loading
Autorzy:
Jebur, Q.H.
Jweeg, M.J.
Al-Waily, M.
Ahmad, H.Y.
Resan, K.K.
Powiązania:
https://bibliotekanauki.pl/articles/2175788.pdf
Data publikacji:
2021
Wydawca:
Stowarzyszenie Komputerowej Nauki o Materiałach i Inżynierii Powierzchni w Gliwicach
Tematy:
rubber
carbon black
filler
hyperelastic models
Abaqus
FEM
guma
sadza
wypełniacz
modele hiperelastyczne
MES
Opis:
Purpose: Rubber is widely used in tires, mechanical parts, and user goods where elasticity is necessary. Some essential features persist unsolved, primarily if they function in excessive mechanical properties. It is required to study elastomeric Rubber's performance, which is operational in high-level dynamic pressure and high tensile strength. These elastomeric aims to increase stress breaking and preserve highly pressurised tensile strength. Design/methodology/approach: The effects of carbon black polymer matrix on the tensile feature of different Rubber have been numerically investigated in this research. Rubber's material characteristics properties were measured using three different percentages (80%, 90%and 100%) of carbon black filler parts per Hundreds Rubber (pphr). Findings: This study found that the tensile strength and elongation are strengthened as the carbon black filler proportion increases by 30%. Practical implications: This research study experimental tests for Rubber within four hyperelastic models: Ogden's Model, Mooney-Rivlin Model, Neo Hooke Model, Arruda- Boyce Model obtain the parameters for the simulation of the material response using the finite element method (FEM) for comparison purposes. These four models have been extensively used in research within Rubber. The hyperelastic models have been utilised to predict the tensile test curves—the accurate description and prediction of elastomer rubber models. For four models, elastomeric material tensile data were used in the FEA package of Abaqus. The relative percentage error was calculated when predicting fitness in selecting the appropriate model—the accurate description and prediction of elastomer rubber models. For four models, elastomeric material tensile data were used in the FEA package of Abaqus. The relative percentage error was calculated when predicting fitness in selecting the appropriate model. Numerical Ogden model results have shown that the relative fitness error was the case with large strains are from 1% to 2.04%. Originality/value: In contrast, other models estimate parameters with fitting errors from 2.3% to 49.45%. The four hyperelastic models were tensile test simulations conducted to verify the efficacy of the tensile test. The results show that experimental data for the uniaxial test hyperelastic behaviour can be regenerated effectively as experiments. Ultimately, it was found that Ogden's Model demonstrates better alignment with the test data than other models.
Źródło:
Archives of Materials Science and Engineering; 2021, 108, 2; 75--85
1897-2764
Pojawia się w:
Archives of Materials Science and Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Granulometric and facies analysis of Middle–Upper Jurassic rocks of Ler Dome, Kachchh, western India: an attempt to reconstruct the depositional environment
Autorzy:
Ghaznavi, Asma A.
Quasim, M. A.
Ahmad, A. H. M.
Ghosh, Sumit K.
Powiązania:
https://bibliotekanauki.pl/articles/94565.pdf
Data publikacji:
2019
Wydawca:
Uniwersytet im. Adama Mickiewicza w Poznaniu
Tematy:
grain size analysis
hydrodynamic conditions
microtexture
sedimentation
marine environment
analiza wielkości ziarna
warunki hydrodynamiczne
mikrotekstura
sedymentacja
środowisko morskie
Opis:
Grain size analysis is an important sedimentological tool used to unravel hydrodynamic conditions, mode of transportation and deposition of detrital sediments. For the present study, detailed grain size analysis was carried out in order to decipher the palaeodepositional environment of Middle–Upper Jurassic rocks of the Ler Dome (Kachchh, western India), which is further reinforced by facies analysis. Microtextures were identified as grooves, straight steps and V-shaped pits, curved steps and solution pits suggesting the predominance of chemical solution activity. Grain size statistical parameters (Graphic and Moment parameters) were used to document depositional processes, sedimentation mechanisms and conditions of hydrodynamic energy, as well as to discriminate between various depositional environments. The grain size parameters show that most of the sandstones are medium- to coarse-grained, moderately to well sorted, strongly fine skewed to fine skewed and mesokurtic to platykurtic in nature. The abundance of medium- to coarse-grained sandstones indicates fluctuating energy levels of the deposition medium and sediment type of the source area. The bivariate plots show that the samples are mostly grouped, except for some samples that show a scattered trend, which is either due to a mixture of two modes in equal proportion in bimodal sediments or good sorting in unimodal sediments. The linear discriminant function analysis is predominantly indicative of turbidity current deposits under shallow-marine conditions. The C-M plots indicate that the sediments formed mainly by rolling to bottom suspension and rolling condition in a beach subenvironment. Log probability curves show that the mixing between the suspension and saltation populations is related to variable energy conditions.
Źródło:
Geologos; 2019, 25, 1; 51-73
1426-8981
2080-6574
Pojawia się w:
Geologos
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The Site Preference Analysis and Ordering Characteristics of Ternary Cu0.5(Zn1–xMx)0.5 (M = Transition Metals) Alloys
Autorzy:
Ahmad, N.
Ziya, A. B.
Atiq, S.
Saifullah, K.
Hashim, M.
Saleem, M.
Powiązania:
https://bibliotekanauki.pl/articles/352693.pdf
Data publikacji:
2018
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
ternary alloy systems
order-disorder transformations
site occupancy
ab-initio calculations
ordering energies
Opis:
The site preference of some transition metals during B2-type ordering has been investigated in the ternary Cu0.5 (Zn1-x Mx )0.5 alloys with M = Ti, V, Ag, Au, Cr, Mn, Fe, Co, Ni, Nb, Mo, Hf, Ta, W, Re or Pt (x ≤ 0.01). The statistic-o-thermodynamical theory combined with the electronic theory of alloys has been used to calculate the partial ordering energies, partial short range order parameters and the order-disorder transformation temperatures. The values of partial short range order parameters have been used to determine the site preference of the metal M. The analysis shows that the metals M can be divided into two groups with regard to lattice site occupancy. One group comprising of Cr, Mn, Fe, Co, Ni, Nb, Mo, Hf, Ta, W, Re or Pt was found to prefer Zn sublattice sites, while the second group of Ti, V, Ag or Au atoms prefer Cu sublattice sites. It is found that order-disorder transformation temperature and the site preference of metal M both depend strongly on the partial ordering energies and ternary alloying addition of metal M.
Źródło:
Archives of Metallurgy and Materials; 2018, 63, 3; 1531-1535
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Statistical Estimation and Mathematical Modelling of Tropospheric Radio Refractivity Based on Meteorological Data
Autorzy:
Alimgeer, K. S.
Awais, M.
Ijaz, B.
Khan, S. A.
Subhan, F.
Ahmad, N.
Powiązania:
https://bibliotekanauki.pl/articles/221069.pdf
Data publikacji:
2018
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
radio refractivity
statistical estimation
ITU
mathematical modelling
Opis:
To obtain optimal performance, estimation of radio refractivity is essential in planning and design of radio links/systems. The dependence of radio refractivity on different climatic parameters such as temperature, pressure, humidity and scale height is studied. The method proposed by International Telecommunication Union (ITU) is used in calculation of tropospheric radio refractivity. The main objective of this work is to formulate a mathematical equation/expression which can be used to predict/estimate the value of radio refractivity for an arbitrary day of any year, with a low error of estimation, in a local environment. Sensitivity of radio refractivity to temperature, pressure and humidity has been evaluated for a period of 5 years from 2008 to 2012, in a particular area under consideration. The results presented for tropospheric radio refractivity take into consideration both the location height and scale height parameters. The results are analysed in terms of statistical measures such as the moving averages, probability density function, monthly mean values, and their corresponding standard deviations. Finally, a mathematical model is formulated to calculate the radio refractivity for any day of a whole year. Reliability of error analysis in respect to accuracy is also shown. It was implemented in the industrial enterprise.
Źródło:
Metrology and Measurement Systems; 2018, 25, 1; 115-128
0860-8229
Pojawia się w:
Metrology and Measurement Systems
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Preparation of Conductive Polyethylene Terephthalate Yarns by Deposition of Silver & Copper Nanoparticles
Otrzymywanie poliestrowych przędz przewodzących poprzez nanoszenie nanocząstek srebra i miedzi
Autorzy:
Ahmad, S.
Ashraf, M.
Ali, A.
Shaker, K.
Umair, M.
Afzal, A.
Nawab, Y.
Rasheed, A.
Powiązania:
https://bibliotekanauki.pl/articles/233073.pdf
Data publikacji:
2017
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Biopolimerów i Włókien Chemicznych
Tematy:
coatings
nanoparticles
technical yarn
smart textiles
powlekanie
nanocząsteczki
przędza
inteligentne tekstylia
Opis:
The assemblage of textiles and electronics in a single structure has led to the development of smart textiles for functional purposes and special products. Conductive yarn as a necessary component of smart textiles is being developed by a number of techniques. The objective of the current study was to impart conductivity to yarn by coating the silver and copper nanoparticles on the surface of multifilament polyester textile fibres. The surface morphology and electrical conductivity of the coated yarns were investigated. The wash ability of the conductive yarns developed was also studied. The yarns showed good retention of the nanoparticles, as proven by the very small loss of the conductivity of the material.
Połączenie tekstyliów i elektroniki w jednej strukturze doprowadziło do rozwoju inteligentnych tekstyliów znajdujących zastosowanie w celach funkcjonalnych i produktach specjalnych. Przędza przewodząca, jako niezbędny składnik inteligentnych wyrobów włókienniczych, może być otrzymywana za pomocą szeregu różnych technik. Celem badania było nadanie przewodnictwa przędzy poliestrowej poprzez powlekanie jej nanocząsteczkami srebra i miedzi. Zbadano morfologię powierzchni i przewodnictwo elektryczne powleczonych przędz, a także ich odporność na pranie. Przędze wykazywały dobrą retencję nanocząstek, co potwierdzała bardzo mała utrata przewodności materiału.
Źródło:
Fibres & Textiles in Eastern Europe; 2017, 5 (125); 25-29
1230-3666
2300-7354
Pojawia się w:
Fibres & Textiles in Eastern Europe
Dostawca treści:
Biblioteka Nauki
Artykuł
Wyświetlanie 1-15 z 19

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