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The purpose of this paper is to establish a simple and practical elastica model for the deflection of weft (warp) in a plain wave fabric.

The weft yarn is considered as an elastic beam fixed supported at the ends and deflected in the middle by a vertical load. An analytical model, based on the elastic theory and small deflection case is adopted to study the factors affecting the deflection of the yarn. To investigate the model, yarns with different rigidities are used. A total of five different yarn counts are produced in the same ring spinning system and then used as weft yarn in a plain weave fabric. All other parameters of the yarns and the fabrics are kept identical. Fresh fabrics are analyzed and the maximum deflection of the weft is measured using the microscope. The actual curves of the deflected weft are then compared with the theoretical curves.

The experimental curves show to agree well with the theoretical model. The results also show that as yarn linear density decreases, the deflection increases.

The paper shows that while the large deformation “elastica” theory is typically used for woven fabric modeling, the small deflection theory can be useful for rapid computation.

Fabric fuzziness is a property which affects the appearance, handle, thermal insulation and other fabric features; it also leads to pilling that is a serious problem for the apparel industry. Fuzz on fabric surface has been measured mostly by subjective methods (human vision) rather than objective methods. In this study, an objective method using image analysis techniques is developed for the measurement of fuzz on fabric surface. The effects of fibers blend ratio and abrasion on fabric fuzziness are evaluated. For this purpose, several blended plain fabrics including polyester/viscose fibers with different blend ratios were produced and abraded under various cycles of traversing abrasion. Yarn hairiness was also measured using an Uster tester 4 apparatus before weaving. High correlation between Uster 4 data and the results obtained from the fuzz measurement of fabrics demonstrates that this method has high accuracy and great potential for the determination of fabric fuzziness levels in a quantitative and reliable manner.

The study aims to monitor the status of open access (OA) journals published in Developing 8 (D-8) countries, i.e. Bangladesh, Egypt, Indonesia, Iran, Malaysia, Nigeria, Pakistan and Turkey.

The authors' web-based data sources for journal-based metrics were the Directory of Open Access Journals (DOAJ), Thomson Reuters (Journal Citation Reports [JCR], which provided journal impact factors [JIF]) and Scopus (source normalized impact per paper [SNIP] and SCImago journal rank [SJR]). The authors obtained information about journals published before 2000 to 2014. From the JCR, JIF, Rank in Category, Total Journals in Category, Journal Rank in Category, and Quartile in Category were used.

The authors' identified 1,407 OAJ published in D-8 countries. Egypt published the most journals (490) and Bangladesh the fewest (29). Egypt, Iran and Turkey accounted for approximately 73.5 per cent of all journals. At the time of study, 10,162 journals were registered in DOAJ, and 13.8 per cent of them were published in D-8 countries. The mean JIF for all journals from individual countries was highest for Pakistan (0.84), followed by Iran (0.74) and Turkey (0.57). The mean SNIP for all journals from each country was highest for Nigeria (0.57), followed by Egypt (0.57) and Pakistan (0.51).

The widespread use of OA publishing models in D-8 countries will boost accessibility of their journals’ content and ultimately impact research in D-8 states.

Journals published in Egypt, Iran and Turkey account for approximately three-fourths of all OA journals published in D-8 countries. More than one-third (38 per cent) of the journals the authors studied used a Creative Commons (CC) BY license, a hallmark of OA research findings. Most of the journals with a JIF were in the JCR Medical Sciences category (60 per cent). As the number of journals in D-8 countries increases, publishers should attempt to make their journals eligible for indexing in-citation databases. The authors recommend efforts to improve the quality of journals in other subject categories, so that as many as possible become eligible for indexing in JCR.

The purpose of this paper is to examine the dimensions of e-service quality, its effects on e-satisfaction and e-trust and its impact on behavioural and attitudinal loyalty in Jordanian youth users of online retailing.

The scale proposed in this study has been specifically constructed using the four models most recognised for measuring e-service quality: E-S-QUAL, WebQual, eTransQual and eTailQ. The dimensions used in this study are efficiency, privacy, reliability, emotional benefit and customer service. The research model was statistically tested by students in Jordan, using Amazon.com.

It is found that privacy, reliability, emotional benefit and customer service are important elements to measure the e-service quality, but efficiency is not. E-trust was found to be an antecedent of e-satisfaction, and behavioural loyalty an antecedent of attitudinal loyalty.

The contribution of this study is thus the investigation of the causal relationship between the e-service quality dimensions, e-satisfaction, e-trust, behavioural loyalty and attitudinal loyalty, where it is necessary to consider the subject in more depth and to examine e-service quality dimensions based on a proposed model constructed from the four most common models.

A fabric can be modeled as an elastic beam supported by simple supports subjected to its own weight. The maximum deflection in the middle can be measured accurately. Different types of fabrics are tested and the bending modulus of the fabrics is then calculated in both small and large deflection cases. In the case of large deflection, the finite element method is used to solve the governing differential equation. The difference between the values of the bending modulus obtained from the small and large deflection cases increases as the length of the bent fabric is increased. The reason is less accuracy of the small deflection equations in longer lengths of the beam. However, the results reveal that even in the longest length of the tested beam (fabric), the differences between the values of the bending modulus from small and large deflection cases are in an acceptable range. It can be concluded that the case of the small deflection can be used to calculate the bending modulus of the fabrics in a simply supported beam method with an acceptable accuracy.

The objective of this research is to investigate various neural network (NN) observer techniques for sensors fault identification and diagnosis of nonlinear system in consideration of numerous faults, failures, uncertainties and disturbances. For the importunity of increasing the faults diagnosis and reconstruction preciseness, a new technique is used for modifying the weight parameters of NNs without enhancement of computational complexities.

Various techniques such as adaptive radial basis functions (ARBF), conventional radial basis functions, adaptive multi-layer perceptron, conventional multi-layer perceptron and extended state observer are presented. For increasing the fault detection preciseness, a new technique is used for updating the weight parameters of radial basis functions and multi-layer perceptron (MLP) without enhancement of computational complexities. Lyapunov stability theory and sliding-mode surface concepts are used for the weight-updating parameters. Based on the combination of these two concepts, the weight parameters of NNs are updated adaptively. The key purpose of utilization of adaptive weight is to enhance the detection of faults with high accuracy. Because of the online adaptation, the ARBF can detect various kinds of faults and failures such as simultaneous, incipient, intermittent and abrupt faults effectively. Results depict that the suggested algorithm (ARBF) demonstrates more confrontation to unknown disturbances, faults and system dynamics compared with other investigated techniques and techniques used in the literature. The proposed algorithms are investigated by the utilization of quadrotor unmanned aerial vehicle dynamics, which authenticate the efficiency of the suggested algorithm.

The proposed Lyapunov function theory and sliding-mode surface-based strategy are studied, which shows more efficiency to unknown faults, failures, uncertainties and disturbances compared with conventional approaches as well as techniques used in the literature.

For improvement of the system safety and for avoiding failure and damage, the rapid fault detection and isolation has a great significance; the proposed approaches in this research work guarantee the detection and reconstruction of unknown faults, which has a great significance for practical life.

In this research, two strategies such Lyapunov function theory and sliding-mode surface concept are used in combination for tuning the weight parameters of NNs adaptively. The main purpose of these strategies is the fault diagnosis and reconstruction with high accuracy in terms of shape as well as the magnitude of unknown faults. Results depict that the proposed strategy is more effective compared with techniques used in the literature.

The purpose of this paper is twofold: first, the authors empirically examine the effect of the perceived values of mobile banking (MB) applications on customers’ e-trust, e-satisfaction and e-loyalty and second, the authors investigate the moderating role of customers’ age in the relationship between perceived value of MB and e-trust.

A survey was conducted on a sample of 361 Tunisian banks’ customers using mobile applications. Structural equation modeling method was performed to test the research hypotheses.

The results of this research revealed that quality, price and emotional perceived values’ dimensions of MB applications are predictors of customers’ e-trust. Within this spectrum, age acts as a moderator in these latter relationships. Findings also suggested that e-trust has positive effects on e-satisfaction and e-loyalty.

This paper presented a reading grid for bank marketers allowing them to identify the levers they must focus their efforts on so as to retain the customers using MB applications. It also permits them to identify the needs and values of three generation of customers, namely baby boomers, generation X and generation Y, so that they can offer better services for each group.

This paper sheds light on an innovative and unexplored topic in the literature. The authors broaden understanding of the relationship between the perceived values of MB applications, e-loyalty, e-trust and e-satisfaction. Research devoted to investigate these different links through an integrative model does exist, yet embryonic. This study also highlights differences between three group of customer, namely baby boomers, generation X and generation Y in terms of perceived values that builds their trust in the context of MB applications use.

This paper aims to design an adaptive nonlinear strategy capable of timely detection and reconstruction of faults in the attitude’s sensors of an autonomous aerial vehicle with greater accuracy concerning other conventional approaches in the literature.

The proposed scheme integrates a baseline nonlinear controller with an improved radial basis function neural network (IRBFNN) to detect different kinds of anomalies and failures that may occur in the attitude’s sensors of an autonomous aerial vehicle. An integral sliding mode concept is used as auto-tune weight update law in the IRBFNN instead of conventional weight update laws to optimize its learning capability without computational complexities. The simulations results and stability analysis validate the promising contributions of the suggested methodology over the other conventional approaches.

The performance of the proposed control algorithm is compared with the conventional radial basis function neural network (RBFNN), multi-layer perceptron neural network (MLPNN) and high gain observer (HGO) for a quadrotor vehicle suffering from various kinds of faults, e.g. abrupt, incipient and intermittent. From the simulation results obtained, it is found that the proposed algorithm’s performance in faults detection and estimation is relatively better than the rest of the methodologies.

For the improvement in the stability and safety of an autonomous aerial vehicle during flight operations, quick identification and reconstruction of attitude’s sensor faults and failures always play a crucial role. Efficient fault detection and estimation scheme are considered indispensable for an error-free and safe flight mission of an autonomous aerial vehicle.

The proposed scheme introduces RBFNN techniques to detect and estimate the quadrotor attitude’s sensor faults and failures efficiently. An integral sliding mode effect is used as the network’s backpropagation law to automatically modify its learning parameters accordingly, thereby speeding up the learning capabilities as compared to the conventional neural network backpropagation laws. Compared with the other investigated techniques, the proposed strategy achieve remarkable results in the detection and estimation of various faults.

Design of bedding textiles that contact the human body affects the sleep quality. Bedding textiles contribute to comfort sense during the sleep duration, in addition to ambient and bed microclimate. The purpose of this study is to evaluate the effects of different layer properties on the compression recovery and thermal characteristics of multilayer bedding textiles.

In this study, woven and knitted multilayer bedding textiles were manufactured from fabric, fiber, sponge and interlining, respectively. Different sponge thickness, fiber and interlining weight were used in the layers of samples. Later, the pilling resistance, compression and recovery, air permeability and thermal conductivity of multilayer bedding textiles were investigated.

The results indicated that samples with the higher layer weight and thickness provide better compression recovery and lower air permeability properties. It was also found that knitted surfaces show the higher air permeability than the woven surfaces depending on the fabric porosity. Layer properties have insignificant effect on the thermal conductivity values.

While researchers mostly focus on thermal comfort properties of garments, there are limited studies about comfort properties of bedding textiles in the literature. Furthermore, compression recovery properties of bedding textiles have also a great importance in terms of comfort. Originality of this study is that these properties were analyzed together.

Open access journals (OAJs) offer immediate, free and unrestricted online access to the scholarly literature. The purpose of this study is to trace the status and characteristics of OAJs published across the globe. Various trends that have evolved in OAJ market have been studied.

The study is based on data collected from one of the largest OA journal directory – Directory of Open Access Journals (DOAJ). The data were downloaded on 02 January 2018 and details of OAJs added to DOAJ till 31 December 2018 were harvested, codified and further analyzed in SPSS software. A Microsoft-Excel template application – MAKESENS – developed by Finnish Meteorological Institute (Finland) in 2002, was explored to perform Mann–Kendall Test and Sen’s Slope Estimates.

A less score of OAJs offer access to their archival content. An increasing trend is witnessed in the OAJ publishing with Elsevier, Sciendo and BioMed Central (BMC) as the top publishers. Majority of publishers are from high-income zone countries, followed by upper-middle and lower-middle zone countries. Majority of OA publishers are from the UK, Indonesia and Brazil. A lesser score of journals offer article processing charges and/or author submission charges. Majority of OAJs from high- and lower-middle-income zone countries levy submission/processing charge to authors compared to OA journals from upper-middle- and lower-income zone countries (p < 0.01). OJS stays a prioritized platform for hosting OA journal content. Portico and CLOCKSS/LOCKSS are mostly used for long-term preservation purposes. Majority of OAJs from high-income zone countries participate in digital arching initiatives compared to ones from other income zones. Majority of the journals adopt a peer review (double-blind peer review, blind peer review, peer review and open peer review) process for validation of their scholarly content. The time lag between submission and publication ranges from one to 53 weeks, with majority of OAJs having a time lag of 11-20 weeks. Creative Commons Licenses are mainly adopted by OAJs.

As the study is based on the data offered by DOAJ, any gaps in the DOAJ data will also get reflected in the study. Further, there might be other OAJs also that have yet to show compliance with DOAJ standards and get indexed with it.

The study tries to showcase the current status and characteristics of OAJs.