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The purpose of this study is to reduce the gloss of the surface of silk fabrics, by treating the fabrics with tea and matting agent, to imitate the aging and retro effects of silk artefacts.

Silk fabrics were treated with different processing techniques. The aged appearance and surface gloss of the silk fabrics were characterised by sensory analysis, measurement of reflectivity, scanning electron microscopy, measurement of brightness and chroma to identify the influential factors.

The application of matting agent on silk fabrics could reduce the lustre of silk fabrics. Treated with matting agent and tea pigments, silk fabrics could be “aged” to achieve retro effects within a relatively short period of time. A number of other factors and mechanisms that affect the reflectivity of the silk fabrics were also identified.

There is no definite index to evaluate the antique effect of fabrics.

The method developed through this study provided a simple and practical solution to achieving aging and retro effects on silk fabrics.

The method for reducing the lustre of silk fabrics by treating them with matting agent is novel and the finding of the relationships among reflectivity and brightness and chroma is original.

The data protection is always a vital problem in the network era. High-speed cryptographic chip is an important part to ensure data security in information interaction. This paper aims to provide a new peripheral component interconnect express (PCIe) encryption card solution with high performance, high integration and low cost.

This work proposes a System on Chip architecture scheme of high-speed cryptographic chip for PCIe encryption card. It integrated CPU, direct memory access, the national and international cipher algorithm (data encryption standard/3 data encryption standard, Rivest–Shamir–Adleman, HASH, SM1, SM2, SM3, SM4, SM7), PCIe and other communication interfaces with advanced extensible interface-advanced high-performance bus three-level bus architecture.

This paper presents a high-speed cryptographic chip that integrates several high-speed parallel processing algorithm units. The test results of post-silicon sample shows that the high-speed cryptographic chip can achieve Gbps-level speed. That means only one single chip can fully meet the requirements of cryptographic operation performance for most cryptographic applications.

The typical application in this work is PCIe encryption card. Besides server’s applications, it can also be applied in terminal products such as high-definition video encryption, security gateway, secure routing, cloud terminal devices and industrial real-time monitoring system, which require high performance on data encryption.

It can be well applied on many other fields such as power, banking, insurance, transportation and e-commerce.

Compared with the current strategy of high-speed encryption card, which mostly uses hardware field-programmable gate arrays or several low-speed algorithm chips through parallel processing in one printed circuit board, this work has provided a new PCIe encryption card solution with high performance, high integration and low cost only in one chip.

This paper aims to comprehensively clarify the research status of thermal transport of supercritical aviation kerosene, with particular interests in the effect of cracking on heat transfer.

A brief review of current research on supercritical aviation kerosene is presented in views of the surrogate model of hydrocarbon fuels, chemical cracking mechanism of hydrocarbon fuels, thermo-physical properties of hydrocarbon fuels, turbulence models, flow characteristics and thermal performances, which indicates that more efforts need to be directed into these topics. Therefore, supercritical thermal transport of n-decane is then computationally investigated in the condition of thermal pyrolysis, while the ASPEN HYSYS gives the properties of n-decane and pyrolysis products. In addition, the one-step chemical cracking mechanism and SST k-ω turbulence model are applied with relatively high precision.

The existing surrogate models of aviation kerosene are limited to a specific scope of application and their thermo-physical properties deviate from the experimental data. The turbulence models used to implement numerical simulation should be studied to further improve the prediction accuracy. The thermal-induced acceleration is driven by the drastic density change, which is caused by the production of small molecules. The wall temperature of the combustion chamber can be effectively reduced by this behavior, i.e. the phenomenon of heat transfer deterioration can be attenuated or suppressed by thermal pyrolysis.

The issues in numerical studies of supercritical aviation kerosene are clearly revealed, and the conjugation mechanism between thermal pyrolysis and convective heat transfer is initially presented.

The MoS₂/graphite composite coatings modified by La₂O₃ through spraying technique were successfully prepared on the inner rings of spherical plain bearings. As a comparison, unmodified coatings were also prepared. This paper aims to study the La-modified MoS₂/graphite composite coating experimentally and improve the tribological performance of self-lubricating spherical plain bearings.

The performance of La₂O₃ toward the friction coefficient, temperature rise and wear rate of the coatings was studied by a self-made tribo-tester under different swing cycles. And the texture, surface morphology and element composition of the coatings were characterized by scanning electron microscope, energy dispersive spectroscopy and X-ray diffractometry.

The additives La₂O₃ refined the coatings’ microstructure and improved the tribological properties of the coatings. The oxidation of Mo + 4 to Mo + 6 was effectively inhibited. And the amount of abrasive grains, peeling pits and local cracks on the coatings surface decreased and homogeneous lubricating films formed, which were attributed to the existence of La₂O₃. The wear mechanisms of unmodified coatings were severe abrasive wear, adhesive wear and delamination wear. However, it exhibited superior wear resistance of the La-modified coatings to unmodified coatings, presenting slight abrasive wear and adhesive wear. The service life of bearings was prolonged under the protection of the modified coatings.

The paper proposed a new modified MoS₂/Graphite composite coating for the self-lubricating spherical plain bearings. The investigation on the friction, wear and temperature increase behaviors and the wear mechanisms of the coatings are beneficial to prolonging the service life of the self-lubricating spherical plain bearings.

Blended wing body (BWB) is a very advantageous design in terms of low fuel consumption, low emission and low noise levels. Because of these advantages, the BWB is a candidate to become the commercial passenger aircraft of the future by providing a paradigm shift in conventional designs. This paper aims to propose a key design parameter for wing sizing of subsonic BWB and a performance parameter for calculating the lift/drag ratio values of BWBs.

The parameter proposed in the study is based on the square/cube law, that is, the idea that the wetted area is proportional to the power of 2/3 of the weight. Data on the weight, wing area, wingspan, lift-to-drag (L/D) ratio for 19 BWB used in the analyzes were compiled from the published literature and a theoretical methodology was developed to estimate the maximum lift to drag ratio of BWBs. The accuracy of the proposed key design parameter was questioned by comparing the estimated L/Dmax values with the actual values.

In the current study, it is claimed that the wingspan/(take-off gross weight)^(1/3) parameter provides an L/D efficiency coefficient regardless of aircraft size. The proposed key design parameter is useful both for small-scale BWB, that is unmanned aerial vehicles BWB and for large-scale BWB designs. Therefore, the b/Wg^(1/3) parameter offers a dimensionless L/D efficiency coefficient for BWB designs of different scales. The wetted aspect ratio explains how low aspect ratio (AR)-BWB designs can compete with high AR-tube-and-wing designs. The key parameter is also useful for getting an idea of good or bad BWB with design and performance data published in the literature. As a result, reducing the blending area and designing a smaller central body are typical features of aerodynamically efficient BWB.

As the role of the square/cube law in the conceptual aircraft design stage has not been sufficiently studied in the literature, the application of this law to BWBs, a new generation of designs, makes the study original. Estimation of the wetted area ratio using only wingspan and gross weight data is an alternative and practical method for assessing the aerodynamic performance of the BWB. According to the model proposed in the current study, reducing the take-off gross weight of the BWBs using lighter building materials and designing with a larger wingspan (b) are the main recommendations for an aerodynamically efficient BWB.

The purpose of this paper is to solve the capacitated location routing problem (CLRP), which is an NP-hard problem that involves making strategic decisions as well as tactical and operational decisions, using a hybrid particle swarm optimization (PSO) algorithm.

PSO, which is a population-based metaheuristic, is combined with a variable neighborhood strategy variable neighborhood search to solve the CLRP.

The algorithm is tested on a set of instances available in the literature and gave good quality solutions, results are compared to those obtained by other metaheuristic, evolutionary and PSO algorithms.

Local search is a time consuming phase in hybrid PSO algorithms, a set of neighborhood structures suitable for the solution representation used in the PSO algorithm is proposed in the VNS phase, moves are applied directly to particles, a clear decoding method is adopted to evaluate a particle (solution) and there is no need to re-encode solutions in the form of particles after applying local search.

As measuring flight performance by experimental methods requires a lot of effort and cost, theoretical models can bring new perspectives to aircraft design. This paper aims to propose a model on the direct calculation of wetted area and L/D_max.

Model is based on idea that the wetted area is proportional to aircraft gross weight to the power of 2/3 (W_g^2/3). Aerodynamic underpinning of this method is based on the square–cube law and the claim that parasitic drag is related to the S_wet/S_wing. The equation proposed by Raymer was used to find the L/D_max estimate based on the calculated wetted area. The accuracy of the theoretical approach was measured by comparing the L/D_max values found in the reference literature and the L/D_max values predicted by the theoretical approach.

Proposed theoretical L/D_max estimate matches with the actual L/D_max data in different types of aircraft. Among the conventional tube-wing design, only the sailplanes have a very low S_wet/S_wing. The S_wet/S_wing of flying wings, blended wing bodies (BWBs) and large delta wings are lower than conventional tube-wing design. Lower relative wetted area (S_wet/S_wing) is the key design criterion in high L/D_max targeted designs.

The proposed model could be used in wing sizing according to the targeted L/D_max value in aircraft design. The approach can be used to estimate the effect of varying gross weight on L/D_max. In addition, the model contributes to the L/D_max estimation of unusual designs, such as variable-sweep wing, large delta wings, flying wings and BWBs. This study is valuable in that it reveals that L/D_max value can be predicted only with aspect ratio, gross weight (W_g) and wing area (S_wing) data.