Raziyeh Erfanifar and Masoud Hajarian
In this paper, the authors study the nonlinear matrix equation
Abstract
Purpose
In this paper, the authors study the nonlinear matrix equation
Design/methodology/approach
The authors present some theoretical results for the existence of the solution of this nonlinear matrix equation. Then the authors propose two iterative schemes without inversion to find the solution to the nonlinear matrix equation based on Newton's method and fixed-point iteration. Also the authors show that the proposed iterative schemes converge to the solution of the nonlinear matrix equation, under situations.
Findings
The efficiency indices of the proposed schemes are presented, and since the initial guesses of the proposed iterative schemes have a high cost, the authors reduce their cost by changing them. Therefore, compared to the previous scheme, the proposed schemes have superior efficiency indices
Originality/value
Finally, the accuracy and effectiveness of the proposed schemes in comparison to an existing scheme are demonstrated by various numerical examples. Moreover, as an application, by using the proposed schemes, the authors can get the optimal controller state feedback of $x(t+1) = A x(t) + C v(t)$.
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A. Hebeish, M. Hashem, M.A. Ramadan, B. Sadek and M. Abdel-Hady
Incorporation of either EDTA or β-cyclodextrin in the bioscouring treatments and its onset on the bioscoured fabrics performance was intensively studied. Biotreatments involved…
Abstract
Incorporation of either EDTA or β-cyclodextrin in the bioscouring treatments and its onset on the bioscoured fabrics performance was intensively studied. Biotreatments involved single use of alkaline pectinase enzyme or in combination with cellulase enzyme in a subsequent treatment. EDTA and β-cyclodextrin were entailed independently in the bioscouring by using two strategies: 1) they were applied to the fabrics as a pretreatment and; 2) they were added to the bioscouring treating solution. Fabrics used were enzymatically desized. Desized fabrics under investigation comprised cotton fabric, mercerized cotton fabric, cotton/polyester (50/50) blend fabric and cotton/polyester (35/65) blend fabric. Results showed that pretreatment of fabrics with EDTA followed by subsequent bioscouring by alkaline pectinase enzyme in single use or in combination with cellulase enzyme in a separate step decreases the performance of bioscoured fabrics. On the other hand, incorporation of EDTA in the bioscouring solution containing alkaline pectinase enzyme alone or together with an extra treatment in the bioscouring solution containing cellulase improves the performance of the bioscoured fabrics. It was also found that addition of β-cyclodextrin to the bioscouring solutions containing alkaline pectinase enzyme alone or supported by cellulase enzyme in a separate step acts in favour of the technical properties and performance of the bioscoured fabrics.
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A. Hebeish, M. A. Ramadan, M. Hashem, B. Sadek and M. Abdel-Hady
A thorough investigation into conditions appropriate for effecting combined eco-friendly scouring and bleaching of cotton based fabrics was undertaken. Loomstate cotton and blend…
Abstract
A thorough investigation into conditions appropriate for effecting combined eco-friendly scouring and bleaching of cotton based fabrics was undertaken. Loomstate cotton and blend fabrics were desized by α-amylase enzyme. Fabrics were the target for bioscouring using alkaline pectinase enzyme, bleaching by in-situ formed peracetic acid using TAED and H2O2 as well as concurrent bioscouring and bleaching which is considered by all means a new development. Also, practiced were the conventional scouring using NaOH followed by bleaching using H2O2 and other bleaching processes vis-à-vis the new current development. The comparison reveals unequivocally that the environmentally sound technology brought about by current development is by far the best. The new development involves a single-stage process for proper purification / preparation of cotton and blend fabrics . through removal of noncellulosic impurities and colouring matters . by padding the fabrics in a bath containing alkaline pectinase enzyme, TAED, H2O2, nonionic wetting agent and sodium silicate. In addition to the advantages related to major technical fabric properties, the new development is eco-friendly and reproducible, which advocates the new development for mill trials.
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Hamdy Mohamed Mohamed and Wael Sabry Mohamed
This study aims to offer an effective nanocomposite for potential use to consolidate and protect deteriorated archaeological pottery.
Abstract
Purpose
This study aims to offer an effective nanocomposite for potential use to consolidate and protect deteriorated archaeological pottery.
Design/methodology/approach
Three nanocomposites were used in the experimental study. This study used nano Primal AC33, silicon dioxide (SiO2) and montmorillonite (MMT) nanoparticles to protect and consolidate pottery specimens. Pottery specimens were made at 800°C for this investigation. Consolidation materials were applied with a brush. The properties of the treated pottery specimens were assessed using several methods such as digital and scanning electron microscopes, static water contact angle, color alteration, physical properties and compressive strength.
Findings
Microscopic examination indicated the ability of the nano Primal AC33/MMT nanocomposites to cover the outer surface well and bind the inner granules. Concerning specimens with code F treated with nano Primal AC33 5%/MMT 3% nanocomposites, it achieved an increase in contact angle (120°), density (1.23 g/cm3) and compressive strength (561 kg/cm2), as well as a decrease in color change (ΔE = 2.62), water absorption (4.45%) and porosity (5.46%). The novelty of the results is due to the characteristics of nano Primal AC33 5%/MMT 3% nanocomposites used in the current study.
Originality/value
This study describes the significant results of the analytical methods used for evaluating consolidation materials used in this study. The findings offer useful information for the protection of archaeological pottery. The investigation indicated that nano Primal AC33 5%/MMT 3% nanocomposites gave the best results. Therefore, it is recommended to use this nanocomposite to consolidate archaeological pottery. As a result, the current work provides a promising first step in conserving archaeological pottery for future studies.
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Kai Yu, Liqun Peng, Xue Ding, Fan Zhang and Minrui Chen
Basic safety message (BSM) is a core subset of standard protocols for connected vehicle system to transmit related safety information via vehicle-to-vehicle (V2V) and…
Abstract
Purpose
Basic safety message (BSM) is a core subset of standard protocols for connected vehicle system to transmit related safety information via vehicle-to-vehicle (V2V) and vehicle-to-infrastructure (V2I). Although some safety prototypes of connected vehicle have been proposed with effective strategies, few of them are fully evaluated in terms of the significance of BSM messages on performance of safety applications when in emergency.
Design/methodology/approach
To address this problem, a data fusion method is proposed to capture the vehicle crash risk by extracting critical information from raw BSMs data, such as driver volition, vehicle speed, hard accelerations and braking. Thereafter, a classification model based on information-entropy and variable precision rough set (VPRS) is used for assessing the instantaneous driving safety by fusing the BSMs data from field test, and predicting the vehicle crash risk level with the driver emergency maneuvers in the next short term.
Findings
The findings and implications are discussed for developing an improved warning and driving assistant system by using BSMs messages.
Originality/value
The findings of this study are relevant to incorporation of alerts, warnings and control assists in V2V applications of connected vehicles. Such applications can help drivers identify situations where surrounding drivers are volatile, and they may avoid dangers by taking defensive actions.
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Sultan Mohammed Althahban, Mostafa Nowier, Islam El-Sagheer, Amr Abd-Elhady, Hossam Sallam and Ramy Reda
This paper comprehensively addresses the influence of chopped strand mat glass fiber-reinforced polymer (GFRP) patch configurations such as geometry, dimensions, position and the…
Abstract
Purpose
This paper comprehensively addresses the influence of chopped strand mat glass fiber-reinforced polymer (GFRP) patch configurations such as geometry, dimensions, position and the number of layers of patches, whether a single or double patch is used and how well debonding the area under the patch improves the strength of the cracked aluminum plates with different crack lengths.
Design/methodology/approach
Single-edge cracked aluminum specimens of 150 mm in length and 50 mm in width were tested using the tensile test. The cracked aluminum specimens were then repaired using GFRP patches with various configurations. A three-dimensional (3D) finite element method (FEM) was adopted to simulate the repaired cracked aluminum plates using composite patches to obtain the stress intensity factor (SIF). The numerical modeling and validation of ABAQUS software and the contour integral method for SIF calculations provide a valuable tool for further investigation and design optimization.
Findings
The width of the GFRP patches affected the efficiency of the rehabilitated cracked aluminum plate. Increasing patch width WP from 5 mm to 15 mm increases the peak load by 9.7 and 17.5%, respectively, if compared with the specimen without the patch. The efficiency of the GFRP patch in reducing the SIF increased as the number of layers increased, i.e. the maximum load was enhanced by 5%.
Originality/value
This study assessed repairing metallic structures using the chopped strand mat GFRP. Furthermore, it demonstrated the superiority of rectangular patches over semicircular ones, along with the benefit of using double patches for out-of-plane bending prevention and it emphasizes the detrimental effect of defects in the bonding area between the patch and the cracked component. This underlines the importance of proper surface preparation and bonding techniques for successful repair.
Graphical abstract
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Faridah Zahra, Rildova Rildova, Sri Murti Adiyastuti and Fajrin Falahi
During its operation, vibrations in jacket platform due to high operational and environmental loads could reduce its productivity and endanger its safety. Tuned mass damper (TMD…
Abstract
Purpose
During its operation, vibrations in jacket platform due to high operational and environmental loads could reduce its productivity and endanger its safety. Tuned mass damper (TMD) is one of the vibration control devices commonly used in buildings to reduce their response. Basically, TMD is a device attached to a structure as a mass on properly tuned spring and damping elements. The purpose of this paper is to study the utilization of TMD to reduce the wave-induced vibration of platforms.
Design/methodology/approach
First, the study investigates the optimum TMD parameters to reduce the response of the platform. The effectiveness of the optimized TMD in reducing platform response due to wave load is then analyzed. Finally, the reduced response of the platform is attributed to an extension of platform service life. Cyclic load in the form of vibration is related to cyclic stress on the tubular connections on a jacket platform, which causes fatigue failure. Fatigue performance of a platform is quantified by its fatigue life, which should be at least twice the intended service life.
Findings
It is found that the optimized TMD cannot be achieved by simply adjusting the TMD damping as high as possible. The results show that the response of controlled platforms by properly tuned TMD could be reduced by about 20 percent from the uncontrolled case.
Originality/value
Although vibration of a structure can be reduced by increasing its stiffness, this approach is considered not economical since it increases the cost for material construction. With the falling of oil prices, an optimization of jacket platform structure is considered necessary to reduce its construction cost. TMD can be used as an alternate solution, even though the only recorded utilization of TMD on a jacket platform is known in Sakhalin Platform in Russia. This fact gives a motivation to carry out more studies about TMD application on jacket platform, as this device is already used in numerous of inland structures.
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Ya Guo, Zhenhua Sun, Xiaoqing Guo, Yanfen Zhou, Liang Jiang, Shaojuan Chen and Jianwei Ma
At present, the enzyme washing process is widely used in hemp garment in the industry. However, it has many disadvantages. First, it is inefficient and labor-intensive, which can…
Abstract
Purpose
At present, the enzyme washing process is widely used in hemp garment in the industry. However, it has many disadvantages. First, it is inefficient and labor-intensive, which can only be produced in small quantities and will take much time for workers to check. Second, its cost is high. The strength loss of the garment is up to 20 percent, with a bad damage. Presently, the enzyme washing process of the gray fabric is not industrialized. The purpose of this paper is to obtain a stable and efficient process for the enzyme washing of the gray fabric.
Design/methodology/approach
The whiteness, weight loss rate, strength, dyeing property and fabric style of enzyme washed gray fabrics were studied.
Findings
The results showed that the enzyme treated fabric has soft handle, smooth surface, good elasticity and high levelness, as well as low strength reduction rate under the optimized condition of bath ratio of 1:12, cellulase dosage of 0.3 percent, pectinase dosage of 1 g/L, treatment temperature of 55°C, treatment time of 80 min and pH of 6.
Originality/value
First, the process is environment friendly, green and sustainable and, second, it will make the industrialization of the enzyme washing process of gray fabrics, with a high commercial value.
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Gang Yu, Zhiqiang Li, Ruochen Zeng, Yucong Jin, Min Hu and Vijayan Sugumaran
Accurate prediction of the structural condition of urban critical infrastructure is crucial for predictive maintenance. However, the existing prediction methods lack precision due…
Abstract
Purpose
Accurate prediction of the structural condition of urban critical infrastructure is crucial for predictive maintenance. However, the existing prediction methods lack precision due to limitations in utilizing heterogeneous sensing data and domain knowledge as well as insufficient generalizability resulting from limited data samples. This paper integrates implicit and qualitative expert knowledge into quantifiable values in tunnel condition assessment and proposes a tunnel structure prediction algorithm that augments a state-of-the-art attention-based long short-term memory (LSTM) model with expert rating knowledge to achieve robust prediction results to reasonably allocate maintenance resources.
Design/methodology/approach
Through formalizing domain experts' knowledge into quantitative tunnel condition index (TCI) with analytic hierarchy process (AHP), a fusion approach using sequence smoothing and sliding time window techniques is applied to the TCI and time-series sensing data. By incorporating both sensing data and expert ratings, an attention-based LSTM model is developed to improve prediction accuracy and reduce the uncertainty of structural influencing factors.
Findings
The empirical experiment in Dalian Road Tunnel in Shanghai, China showcases the effectiveness of the proposed method, which can comprehensively evaluate the tunnel structure condition and significantly improve prediction performance.
Originality/value
This study proposes a novel structure condition prediction algorithm that augments a state-of-the-art attention-based LSTM model with expert rating knowledge for robust prediction of structure condition of complex projects.