•Biomass energy pellets were pyrolysed to produce fuels in the Pyroformer system.•Barley straw oil has a higher calorific value, but reduced yield and quality.•Wood and barley straw produce similar ...permanent gas and char.•The overall product energy yields are over 73% for wood and barley straw.
This work describes the use of intermediate pyrolysis system to produce liquid, gaseous and solid fuels from pelletised wood and barley straw feedstock. Experiments were conducted in a pilot-scale system and all products were collected and analysed. The liquid products were separated into an aqueous phase and an organic phase (pyrolysis oil) under gravity. The oil yields were 34.1wt.% and 12.0wt.% for wood and barley straw, respectively. Analysis found that both oils were rich in heterocyclic and phenolic compounds and have heating values over 24MJ/kg. The yields of char for both feedstocks were found to be about 30wt.%, with heating values similar to that of typical sub-bituminous class coal. Gas yields were calculated to be approximately 20wt.%. Studies showed that both gases had heating values similar to that of downdraft gasification producer gas. Analysis on product energy yields indicated the process efficiency was about 75%.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
This study proposes an optimization-based strategy to select the best electrical stacking configuration of microbial fuel cells to achieve the highest power output and chemical oxygen demand removal ...under the lowest operating costs. Three similar wastewater-fed continuous flow microbial fuel cells are electrically connected in four different modes and concentrations of fuel substrate and buffer in anolyte, as main operating cost items, are optimized using two-level factorial design with the dual objective of maximizing power density and minimizing operating costs. In series connection the lowest ratio of operating costs to maximum power $0.048.mW−1.d−1 is achieved that is comparable to the ratio of $0.046.mW−1.d−1 for an individual unit as control. Optimization reduces operating costs 61% with only 37% reduction in maximum power compared to maximum attainable power. At the optimized concentrations, the lowest operating costs to chemical oxygen demand removal ratio $2.01.COD−1 is observed in series connection. This suggests that the cheapest way to stack microbial fuel cells to gain the highest power output and chemical oxygen demand removal is serial electrical connection.
•A new optimization-based strategy for stacking MFC units is proposed.•Any number of MFC units in any configuration can be tested to find out the best stacking configuration.•The best stacking configuration is separately optimized in terms of minimum cost for maximum power output and COD reduction.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Despite the rapid evolution of Internet protocol-based messaging services, SMS still remains an indisputable communication service in our lives until today. For example, several businesses consider ...that text messages are more effective than e-mails. This is because 82% of SMSs are read within 5 min., but consumers only open one in four e-mails they receive. The importance of SMS for mobile phone users has attracted the attention of spammers. In fact, the volume of SMS spam has increased considerably in recent years with the emergence of new security threats, such as SMiShing. In this paper, we propose a hybrid deep learning model for detecting SMS spam messages. This detection model is based on the combination of two deep learning methods CNN and LSTM. It is intended to deal with mixed text messages that are written in Arabic or English. For the comparative evaluation, we also tested other well-known machine learning algorithms. The experimental results that we present in this paper show that our CNN-LSTM model outperforms the other algorithms. It achieved a very good accuracy of 98.37%.
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CEKLJ, DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
A new aromatic Schiff base with azo linkage has been synthesized and characterized by FT-IR,
1
H-NMR, and
13
C-NMR spectroscopy. The new compound ...2-(((5-mercapto-1,3,4-thiadiazol-2-yl)imino)methyl)-4-(p-tolyldiazenyl)phenol (5, denoted as AT) was tested as a carbon steel corrosion inhibitor in 1 M H
2
SO
4.
The presence of AT in 0.04 mM concentration at 303 K achieved excellent inhibition efficiency values, 96.6 and 97.4% by potentiodynamic polarization and weight loss measurements, respectively. The adsorption process of AT on carbon steel surface was found to obey Langmuir adsorption isotherm with the highest K
ads
value 476,190 M
−1
at 313 K, and ΔG values −25.53, −26.49, −25.97, and −25.78) kJ mol
−1
over the studied range of temperatures 303-333 K, indicating the spontaneous formation of stable protection film through a strong adsorption process. Density function theory (DFT) studies were employed for further investigations about the nature of the interaction between the molecules of AT (both of its tautomers) and metal surface. SEM and AFM analysis were used to confirm the inhibition by comparing the morphology of the corroded surface with the inhibited one.
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BFBNIB, DOBA, GIS, IJS, IZUM, KILJ, KISLJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
This qualitative exploratory study assesses the technological disruptions in restaurant services caused by innovations in food delivery. A systematic review of the restaurant classification for the ...past two decades showed that the use of the term “restaurant delivery service” increased significantly since 2014 and is now used as often as “fast food service.” An improved typology of services as affected by technology is presented. A hypothetical model was developed to show the hierarchical progression of restaurant services as affected by technological innovations. Technological disruptions were categorized at different stages. The theory of disruptive innovation was assessed, and a hypothesis is presented to relate the impact on delivery services. Major disruptions identified are in the restaurant terminology/classification, widening of the distance between the service provider and customer contact points, and the potential collateral disruption to the service quality. Opportunities and challenges related to disruptions are identified.
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NUK, OILJ, SAZU, UKNU, UL, UM, UPUK
New Azo Schiff compound namely 4-((4-hydroxy-3-((pyridine-2-ylimino)methyl)phenyl)diazenyl)benzonitrile (5) which is denoted as AS was synthesized and characterized using FT-IR, 13C NMR and 1H NMR ...spectroscopy. The new compound was evaluated as corrosion inhibitor for carbon steel in 1 M H2SO4, using electrochemical and gravimetric techniques. Tween-80 surfactant was added to enhance the solubility of AS in the acidic medium. The inhibition efficiency was found to be dependent on the concentration of AS and temperature, the highest inhibition efficiency values (91.32% and 90.30% by potentiodynamic and weight loss measurements respectively) were recorded in the presence of relatively low concentration of AS (0.08 mM) at 303 K, and it acts as anodic inhibitor. To understand the mechanism of the corrosion inhibition, the adsorption of AS onto carbon steel surface was studied, the results indicated that the adsorption process obeys Langmuir adsorption isotherm, the calculated ΔGads values were found to be around −37 kJ mol−1 which indicates that AS is adsorbed on the carbon steel surface by chemical and physical interactions. For further investigations DFT studies were employed to explain the nature of interaction between the AS molecules (neutral and protonated) and metal surface. Finally, the morphology of both corroded and inhibited surfaces were studies by scanning electron microscopy (SEM) and atomic force microscopy (AFM) techniques which confirmed the high inhibition efficiency of AS at the optimum conditions, a significant reduction in the distortion and roughness of the surface were observed (the surface roughness was reduced from 17.10 nm to 2.15 nm as measured by AFM).
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•New aromatic Azo-Schiff (AS) compound is synthesized via two steps.•The new compound is evaluated as carbon steel corrosion inhibitor in 1 M H2SO4.•A nonionic surfactant Tween-80 is used to enhance the solubility of the inhibitor.•Electrochemical, gravimetric, SEM and AFM data confirms that AS is an excellent anodic carbon steel corrosion inhibitor.•The adsorption of AS on carbon steel surface obeys Langmuir adsorption isotherm.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Recently, smart home devices have been widely used to assist and facilitate the lives of human beings. Human activity recognition (HAR) aims to identify human activities using sensors in smartphones. ...Therefore, it can be employed in many applications, such as remote health monitoring for disabled and elderly people. This paper proposes a granular computing-based approach to classifying human activities using wearable sensing devices. The approach has two main phases: feature selection and classification. In the feature selection phase, the approach attempts to remove redundant and irrelevant attributes. At the same time, the classification phase makes use of granular computing concepts to build the granules and find the relationships between granules at different levels. To evaluate the approach, we applied the dataset to five famous machine learning models. For the comparative evaluation, we also tested other well-known machine learning methods. The experimental results presented in this paper show that the approach outperformed common traditional classifiers in terms of classification precision recall, f-measure, and MCC for most recognized human activities by approximately 97.3%, 94%, 95.5%, and 94.8%, respectively. However, in terms of processing time, it performs comparably.
•This paper is a result of a pursuit to systematically and comparatively assess the collaboration or a lack of between academia and hospitality industry, primarily in relation to research during the ...past 30 years.•Six different gaps were identified between academic and hospitality industry research and described in detail.•Recommendations for bridging the gaps between academia and hospitality industry are listed.
This paper is an outcome of a pursuit to assess the collaboration or a lack of, between academia and hospitality industry during the past 30 years. The primary objective was to investigate if there are any gaps between the academic research and hospitality industry collaboration, using a qualitative assessment of selected data for the past several years. Sources of information include: (a) all published papers in peer-reviewed hospitality journals from 1988 to 2017 and (b) a secondary systematic review of all papers (161) published in the Journal of Hospitality & Tourism Research from the year 2013–2017 for analyses of practical/managerial implications mentioned by authors. As a result of systematic assessment, six different gaps were identified which are described in detail. Finally, possible ideal collaboration between academe and hospitality industry is discussed considering the existing gaps. Possible recommendations for bridging the gaps are listed.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Mobile ad hoc networks (MANETs) are being used more and more in a variety of fields, including the environment, energy efficiency, smart transportation, intelligent agriculture, and in Internet of ...Things (IoT) ecosystems. They are also anticipated to play an increasingly significant role in the future of the Internet due to the strong evolution of wireless technology in recent years. Nevertheless, this inter-node communication is vulnerable to various security attacks such as Man–In-The-Middle (MITM) attacks, which are considered to be the main challenge in MANETs. This happens when a harmful node intercepts data shared by legal nodes. Therefore, the main goal of this work is to investigate the impact of attackers’ strategies to execute MITM assaults in MANETs, such as message-delayed and message-dropped assaults. The output of this work shows that these assaults have a severe impact on legal entities in MANETs as the network experiences a high number of compromised messages as well as high E2ED and PLD. Finally, by using symmetry or asymmetry cryptographies, our proposal will avoid MITM attacks that intercept the communication between legal nodes.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Fifth-generation (5G)-enabled vehicular fog computing technologies have always been at the forefront of innovation because they support smart transport like the sharing of traffic data and ...cooperative processing in the urban fabric. Nevertheless, the most important factors limiting progress are concerns over message protection and safety. To cope with these challenges, several scholars have proposed certificateless authentication schemes with pseudonyms and traceability. These schemes avoid complicated management of certificate and escrow of key in the public key infrastructure-based approaches in the identity-based approaches, respectively. Nevertheless, problems such as high communication costs, security holes, and computational complexity still exist. Therefore, this paper proposes an efficient certificateless authentication called the ECA-VFog scheme for fog computing with 5G-assisted vehicular systems. The proposed ECA-VFog scheme applied efficient operations based on elliptic curve cryptography that is supported by a fog server through a 5G-base station. This work conducts a safety analysis of the security designs to analysis the viability and value of the proposed ECA-VFog scheme. In the performance ovulation section, the computation costs for signing and verification process are 2.3539 ms and 1.5752 ms, respectively. While, the communication costs and energy consumption overhead of the ECA-VFog are 124 bytes and 25.610432 mJ, respectively. Moreover, comparing the ECA-VFog scheme to other existing schemes, the performance estimation reveals that it is more cost-effective with regard to computation cost, communication cost, and energy consumption.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
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