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Double-jacquard technique is referred as the most advanced technology for forming patterns on both layers of a 3D fabric knitted on a double-needle bar warp-knitting machine. In order to realize the computer-aided design and simulation of jacquard patterns, the purpose of this paper is to propose a mathematic model for representation of jacquard structures and an improved mass-spring model to improve the simulation of structural deformation behavior.

Primarily, it analyzes the jacquard patterning method and displacing principle to design jacquard structures on each layer and linking structures of two layers. Based on that, a loop geometry defined by six key points and segmental lines is built to transfer the jacquard bitmap and lapping movements into a fabric of loops and therefore realizing patterns visualization. Afterwards, an improved mass-spring model is built to simulate structural deformation, in which the fabric is simplified as a mesh of uniformly distributed mass particles. Each loop is treated as a massless particle while underlaps are referred as structural springs connecting loops particles. Elastic forces of these springs on each loop particle is calculated according to the Hook’s law and Newton’s second law, and then based on the explicit Euler’s equations, motion state of each particle is solved including the velocity and the shift.

Based on the above method, a simulator for double-layer jacquard fabrics is developed via Visual C++ language to visualize the patterned fabrics with pitting effects. With a jacquard shoe fabric as an example, this simulation model is proved to be practical and efficient by comparing the simulation result and real fabric.

Because of limited researches, 3D simulation modeling of this double-layer jacquard fabric will be studied in the further research.

The implement of this simulation method will offer the industries a time-saving and cost-saving approach for new fabrics development.

This approach can be used as a reference for simulating other knitted fabrics with jacquard patterns, such as jacquard garment fabrics and home textile fabrics.

The obtained simulation structures could reflect the appearances and the features of the fabrics. The purpose of this paper is to promote a lot for design and manufacturing of weft-knitted lace fabrics (WKLF).

The advantages of WKLF compared with warp-knitted ones were displayed. The formation mechanism of the WKLF was analyzed with employing the mechanics principles. Spring-mass model was proposed in this paper to achieve the simulation of the fabrics. End mass points and intermediate mass points were involved in the model. The displacement of end mass points was considered the dominance and the foundation to settle the positions of all the mass points.

A novel jacquard lace style fabric with pattern-background effect knitted on circular knitting machine were put forward, which were different from the traditional lace fabrics manufactured on the warp knitting machines.

First, as the manufacturing equipment, circular knitting machine costs much less than warp knitting machine; second, the elastic performance along weft direction of WKLF is more excellent than that of warp-knitted ones. Third, the excellent extensibility gives nice comfort; furthermore, long floating threads do not exist on the WKLF surface, so that the snag will be avoided.

The weft-knitted two-side jacquard fabric has the characteristics of complicated design principle and hard technical design. The purpose of this paper is to realize the computer-aided design of weft-knitted two-side jacquard fabric, and provide a certain reference for the development of this type of fabric.

The weft-knitted two-side jacquard fabric is divided into weft-knitted two-side similar pattern jacquard fabric and weft-knitted two-side independent pattern jacquard fabric. In order to achieve the purpose of this study, firstly, the structural characteristic of weft-knitted two-side jacquard fabric is analyzed. Then, the design principle of weft-knitted two-side jacquard fabric is studied. Next, the technical model of weft-knitted two-side jacquard fabric is established. Finally, the CAD flow chart of weft-knitted two-side jacquard fabric is proposed to realize the rapid product development.

Based on the above method, through the development example of weft two-side similar pattern jacquard fabric and weft two-side independent pattern jacquard fabric, the computer-aided design of the weft two-side jacquard fabric is verified.

Because of limited research studies, three-dimensional computer-aided design of weft-knitted two-side jacquard fabric loop structure will be studied in the further research, and the technical design speed needs to be improved to meet the needs of large patterns and positioning patterns.

The computer-aided design of weft-knitted two-side jacquard fabric will offer a certain reference for product development, technical principles, performance research and computer simulation for the in-depth study of the fabric.

The computer-aided design of weft-knitted two-side jacquard fabric will simplify the fabric design process and improve the efficiency of new fabric development, and provide the industries a time-saving and cost-saving approach for new fabrics development.

The author analyzes the structural characteristic of the fabric by the physical fabric, summarizes design principle of the fabric through production process, uses mathematical methods to establish a three-dimensional technical model of the fabric, and proposes the CAD flow chart of weft-knitted two-side jacquard fabric, which has good theoretical significance and practice of weft-knitted two-side jacquard fabric.

Realistic geometric description is essential for simulating physical properties of warp-knitted velvet fabrics, which are widely used for home-textiles and garments. The purpose of this paper is to provide an approach to the description of patterned piles and propose a customized simulation model to realize highly real-time simulation of warp-knitted velvet fabrics in three dimensions.

Based on knitting technology and structure features, a mathematical model to qualify forming possibility of piles is conducted by assessing underlaps of pattern bars and pile ground bars. When the pile areas and ground areas are classified, a three-dimensional (3D) space coordinate is built, of which the z-axis is divided into equal spaces to form certain multi-layer textured slices. Color and transparency of piles on each textured slice can be computed and generated by mapping to 3D geometrical grid layers with particular mapping relationship. Moreover, piles’ deflection and spatial collision are also taken into account to make sure high uniformity with real fabrics.

According to the models built, a simulator special for warp-knitted patterned velvet fabrics is programed via Visual C++ and the models are proven practical and easily implemented by comparing simulated effect of one sample with real fabric.

Because of present limited research, 3D simulation of patterned velvet fabrics knitted on double-needle bar Raschel machine as well as 3D shadow effect will be studied in the further research.

The paper includes implications for designing patterned velvet products and shows convenience to instantly see finished effect without sampling on machine.

This paper fulfills a featured simulation method for warp-knitted patterned velvet fabrics in 3D dimensions for the first time.

Bdellovibrio bacteriovorus is a gram-negative predatory bacterium which can potentially inhibit microbiologically influenced corrosion by preying on sulfate-reducing bacteria (SRB). However, no researches about the inhibition are reported according to the authors’ knowledge. The purpose of this paper was to investigate the Inhibition effect of B. bacteriovorus on the corrosion of X70 pipeline steel induced by SRB.

The effect of B. bacteriovorus on the growth of SRB was studied by measuring the optical density at 600 nm (OD600) and sulfate concentration in culture medium. X70 pipeline steel was used as the test material to investigate the anti-corrosion effect of B. bacteriovorus on SRB by conducting electrochemical analysis (including Tafel polarization curves and electrochemical impendence spectroscopy) and weight loss measurement.

B. bacteriovorus could inhibit the growth of SRB in culture medium by its predation on SRB, which led to decrease of OD600 value and increase of sulfate concentration. The results of electrochemical analysis indicated that B. bacteriovorus had positive inhibition efficiencies on SRB-induced corrosion of X70 pipeline steel. Moreover, corrosion rate of X70 pipeline steel was declined from 19.17 to 3.75 mg·dm-2·day-1 by the presence of B. bacteriovorus.

This is the first report about using B. bacteriovorus to inhibit the corrosion induced by SRB. Compared to other anti-corrosion methods, the microbial inhibition methods exhibit more considerable application value due to its low cost, high efficiency and non-pollution.

Sulfate-reducing bacteria (SRB) are recognized by scholars as the most important class of bacteria leading to corrosion of metal materials. It is important to use the properties of microorganisms to inhibit the growth of SRB in the corrosion protection of metal materials and to protect the environment.

In this work, the behavior of anaerobic Thiobacillus denitrificans (TDN) intracellular enzyme inhibition of SRB corrosion of EH36 steel was investigated with electrochemical impedance spectroscopy, biological detection technology and X-ray photoelectron spectroscopy.

Results showed that the SRB crude intracellular enzyme affected the corrosion behavior of EH36 steel greatly and the purified TDN intracellular enzyme inhibits SRB intracellular enzyme corrosion to EH36 steel.

A perfect enzyme activity inhibition mechanism will provide theoretical guidance for the selection and application of anticorrosion microorganisms, which is of scientific significance in the field of microbial anticorrosion research.

This paper aims to contribute to the performance improvement and the broader application of hot-dip galvanized coating.

First, the ability to provide barrier protection, galvanic protection, and corrosion product protection provided by hot-dip galvanized coating is introduced. Then, according to the varying Fe content, the growth process of each sublayer within the hot-dip galvanized coating, as well as their respective microstructures and physical properties, is presented. Finally, the electrochemical corrosion behaviors of the different sublayers are analyzed.

The hot-dip galvanized coating is composed of η-Zn sublayer, ζ-FeZn13 sublayer, δ-FeZn10 sublayer, and Γ-Fe3Zn10 sublayer. Among these sublayers, with the increase in Fe content, the corrosion potential moves in a noble direction.

There is a lack of research on the corrosion behavior of each sublayer of hot-dip galvanized coating in different electrolytes.

It provides theoretical guidance for the microstructure control and performance improvement of hot-dip galvanized coatings.

The formation mechanism, coating properties, and corrosion behavior of different sublayers in hot-dip galvanized coating are expounded, which offers novel insights and directions for future research.

The promotion of new energy vehicles (EVs) is an effective way to achieve low carbon emission reduction. This paper aims to investigate the optimal pricing of automotive supply chain members in the context of dual policy implementation while considering consumers' low-carbon preferences.

This article takes manufacturers, retailers and consumers in a main three-level supply chain as the research object. Stackelberg game theory is used as the theoretical guidance. A game model in which the manufacturer is the leader and the retailer is the follower is established. The author also considered the impact of carbon tax policies, subsidy policies and consumer preferences on the results. Furthermore, the author investigates the optimal decision-making problem under the profit maximization model.

Through model solving, it is found that the pricing of EVs is positively correlated with the unit price of carbon and the amount of subsidies. The following conclusions can be obtained by numerical analysis of each parameter. Changes in carbon prices have a greater impact on conventional gasoline vehicles. Based on the numerical analysis of parameter β, it is also found that when the government subsidizes consumers, supply chain members will increase their prices to obtain partial subsidies. Compared with retailers, low-carbon preferences have a greater impact on manufacturers.

The new energy automobile industry involves many policies, including tax cuts, tax exemptions and subsidies. The policy environment faced by the members of a supply chain is complex and diverse. Therefore, the analysis in this article is based only on partial policies.

The authors innovatively combine the three factors of subsidy policy, carbon tax policy and consumer low-carbon preference, with research on the pricing of EVs. The influence of policy factors and consumer preferences on the pricing of EVs is studied.

The purpose of this paper is to propose a high angle of attack short landing model for switched polytopic systems as well as to derive an equation for fluidic thrust vector deflection angle based on pressure to reduce the velocity during the landing phase of flight.

In this paper, robust control algorithm is proposed for a non-linear high angle of attack aircraft under the effects of non-linearities, tottering hysteresis, irregular and wing rock atmosphere. High angle of attack short landing flight under asynchronous switching is attained by using the robust controller method. Lyapunov function and the average dwell time scheme is used for obtaining the switched polytopic scheme. The asynchronous switching and loss of data are controlled asymptotically. The velocity of aircraft has been lucratively reduced during the landing phase of flight by using the robust controller technique.

The proposed algorithm based on robust controller including the effects of non-linearities guarantee the successful reduction of velocity for high angle of attack switched polytopic systems.

As the landing phase of an aircraft is one of the complicated stage, this algorithm plays a vital role in stable and short landing under the condition of high angle of attack (AOA).

In this paper, not only the velocity of flight has been reduced, but also the high angle of attack has been attained during the landing phase, because of which the duration of landing has been reduced as well, while in most of the previous research, it is based on low angle of attack and long landing duration.

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.