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This study aims to investigate the design and optimization of landing gear buffers to improve the landing-phase comfort of civil aircraft.

The vibration comfort during the landing and taxiing phases is calculated and evaluated based on the flight-testing data for a type of civil aircraft. The calculation and evaluation are under the guidance of the vibration comfort standard of GB/T13441.1-2007 and related files. The authors establish here a rigid-flexible coupled multibody dynamics finite element model of one full-size aircraft. Furthermore, the authors also implement a dynamic simulation for the landing and taxiing processes. Also, an analysis of how the main parameters of the buffers affect the vibration comfort is presented. Finally, the optimization of the single-chamber and double-chamber buffers in the landing gear is performed considering vibration comfort.

The double-chamber buffer with optimized parameters in landing gear can improve the vibration comfort of the aircraft during the landing and taxiing phases. Moreover, the comfort index can be increased by 25.6% more than that of a single-chamber type.

To the best of the authors’ knowledge, this study first investigates the evaluation methods and evaluation indexes on the aircraft vibration comfort, then further conducts the optimization of the parameters of landing gear buffer with different structures, so as to improve the comfort of aircraft passengers during landing process. Most of the current studies on aircraft landing gear have focused on the strength and safety of the landing gear, with very limited research on cabin vibration comfort during landing and subsequent taxiing because of the coupling of runway surface unevenness and airframe vibration.

Strain sensors have been widely used to measure the strain of the structure. However, the ordinary sensing elements are not suitable for measuring large deformation on an irregular surface, which limits their applications. Recently, flexible sensors have attracted extensive interest because they can overcome the shortage of the ordinary sensing elements. The paper aims to discuss this issue.

In this paper, the whole measurement process of strain sensing behavior and the dimension design of fle3xible strain sensing system use the macroscopic measurement method of material tensile test to accurately measure the resistance change with strain. Afterwards, combining electrical components, the flexible strain sensors are produced for two biomedical applications: the wearable data-collecting gloves and rehabilitation training system.

The results show that the developed conductive fabric can exhibit high sensitivity, large workable strain range (>50 percent) under simple and repeated tension and good stability. Both applications demonstrate that the polypyrrole-coated fabric sensor can successfully measure the large and repeat strain, capture the motion of body and display corresponding information almost in real time.

The limitation lies in the lack of a holistic strain sensing mechanism study, and the lack of a corresponding theoretical model to explain the experimental results.

The purpose of this paper is to improve the tribological properties of aluminum cylinder liner. Higher martensite contents were closely related to the higher hardness and excellent wear resistance of Fe-based coatings. Furthermore, the grain size of the Fe-based coating was approximately 40 nm, which provides an excellent fine grain strengthening effect.

To improve the tribological properties of aluminum cylinder liners, a Fe-based martensite coating was prepared by internal plasma spraying technology, whose microstructure and tribological properties were then investigated.

Sprayed Fe-based coating possessed a low contact angle and strong adhesion with lubricating oil. In a simulated engine condition, Fe-based coating exhibited a decreased friction coefficient and increased wear resistance under oil lubrication, which was dominated by a stronger adhesive force with lubricating oil, higher martensite contents on the worn surface, higher hardness and higher H/E value than those of the reference HT 200 and Al-19Si cylinder material.

Nanostructure Fe-based martensite coating was sprayed on an aluminum cylinder liner, which demonstrated remarkable advantages over the reference cylinder material.

The purpose of the paper is to improve the calculability of a continuum damage failure model of composite laminates based on Tsai-Wu criteria.

A technique based on viscous regularization, a characteristic element length and fracture energies of fiber and matrix are used in the model.

The calculability of the material model is improved. The modified model can predict the behavior of composite structure better.

The convergence problem and the mesh softening problem are main concern in the calculability of numerical model. In order to improve the convergence, a technique based on viscous regularization of damage variable is used. Meanwhile, characteristic element length and fracture energies of fiber and matrix are added into the damage constitutive equation to reduce the mesh sensitivity of numerical results. Finally, a laminated structure with damages is implemented using a User Material Subroutine in ABAQUS/Standard. Mesh sensitivity and value of viscosity are discussed.

An interferogram is produced by modulating the difference between the extraordinary refractive index and the ordinary refractive index for photoelastic crystals in photoelastic-modulated Fourier transform spectrometers (PEM-FTs). Due to the influence of the refractive index dispersion characteristics on the maximum optical path difference of the interferogram, it is necessary to study wavelength calibration methods.

A wavelength calibration method for PEM-FTs was proposed based on the modulation principle of the photoelastic-modulated interferometer and the relationship between the maximum optical path difference and the refractive index difference. A 632.8 nm narrow-pulse laser was used as a reference source to measure the maximum optical path difference () of the interferogram, and the parameter was used to calculate the discrete frequency points in the frequency domain. To account for the influence of refractive index dispersion on the maximum optical path difference, the refractive index curve for the photoelastic crystal was used to adjust the discrete frequency coordinates.

The error in the reconstructed spectral frequency coordinates clearly decreased. The maximum relative error was 2.5%. A good solar absorption spectrum was obtained with a PEM-FT experimental platform and the wavelength calibration method.

The interferogram is produced by adjusting the difference between extraordinary refractive index and ordinary refractive index for the photoelastic crystal in the PEM-FTs. Given the wavelength dependence on the refractive indices, in view of the modulation principle of the photoelastic modulated interferometer, the relationship between the maximum optical path difference and the refractive index difference, the variation law of the refractive index of the photoelastic crystal and the process of spectral reconstruction is presented in this paper.

The purpose of this paper is to accurately obtain the deformation of a hybrid robot and rapidly enable real-time compensation in friction stir welding (FSW). In this paper, a prediction algorithm based on the back-propagation neural network (BPNN) optimized by the adaptive genetic algorithm (GA) is presented.

Via the algorithm, the deformations of a five-degree-of-freedom (5-DOF) hybrid robot TriMule800 at a limited number of positions are taken as the training set. The current position of the robot and the axial force it is subjected to are used as the input; the deformation of the robot is taken as the output to construct a BPNN; and an adaptive GA is adopted to optimize the weights and thresholds of the BPNN.

This algorithm can quickly predict the deformation of a robot at any point in the workspace. In this study, a force-deformation experiment bench is built, and the experiment proves that the correspondence between the simulated and actual deformations is as high as 98%; therefore, the simulation data can be used as the actual deformation. Finally, 40 sets of data are taken as examples for the prediction, the errors of predicted and simulated deformations are calculated and the accuracy of the prediction algorithm is verified.

The entire algorithm is verified by the laboratory-developed 5-DOF hybrid robot, and it can be applied to other hybrid robots as well.

Robots have been widely used in FSW. Traditional series robots cannot bear the large axial force during welding, and the deformation of the robot will affect the machining quality. In some research studies, hybrid robots have been used in FSW. However, the deformation of a hybrid robot in thick-plate welding applications cannot be ignored. Presently, there is no research on the deformation of hybrid robots in FSW, let alone the analysis and prediction of their deformation. This research provides a feasible methodology for analysing the deformation and compensation of hybrid robots in FSW. This makes it possible to calculate the deformation of the hybrid robot in FSW without external sensors.

The purpose of this paper is to demonstrate how food waste management can affect both retail and distribution operators’ efficiency performance and their ability to create value. In particular, the paper shows how optimizing food waste management characterizes best practices and favors the development of sustainability.

Based on a survey of 196 outdoor market operators (including farmers and street food traders) from 27 outdoor markets, the authors analyzed unsold food/food wastage processes vis-à-vis the operators’ behavior and attitude. To provide accurate definitions of the satisfaction levels, a consumer perception survey was carried out, with a usable sample of 2,107 questionnaires. The efficiency performance was evaluated according to data envelopment analysis.

The results showed that farmers operate more efficiently than street food traders and that the traditional management of unsold food/food waste is an important competitive element in this sector.

The sample represents the Greater Turin Area in Italy, i.e., thus, limiting generalizability of the results. In addition, the variables analyzed were limited to certain aspects of selling processes and food waste management.

The results provide some indicators on how a more rational style of unsold food management can improve an operators’ performance and help make a social impact.

To the best of the authors’ knowledge, this is the first study that analyses outdoor market operators’ efficiency, based on the use of food waste as a variable affecting their performance.

Examines the tenth published year of the ITCRR. Runs the whole gamut of textile innovation, research and testing, some of which investigates hitherto untouched aspects. Subjects discussed include cotton fabric processing, asbestos substitutes, textile adjuncts to cardiovascular surgery, wet textile processes, hand evaluation, nanotechnology, thermoplastic composites, robotic ironing, protective clothing (agricultural and industrial), ecological aspects of fibre properties – to name but a few! There would appear to be no limit to the future potential for textile applications.

Examines the ninth published year of the ITCRR. Runs the whole gamut of textile innovation, research and testing, some of which investigates hitherto untouched aspects. Subjects discussed include cotton fabric processing, asbestos substitutes, textile adjuncts to cardiovascular surgery, wet textile processes, hand evaluation, nanotechnology, thermoplastic composites, robotic ironing, protective clothing (agricultural and industrial), ecological aspects of fibre properties – to name but a few! There would appear to be no limit to the future potential for textile applications.

The paper's aim is to study tribological performances of two 2‐mercaptobenzothiazole derivatives which are ashless and lacking in phosphorous as lubricating oil additives in HVIW H150 base oils.

The two 2‐mercaptobenzothiazole derivatives were synthesized; their tribological performances were evaluated with a four‐ball machine, and the worn surface was analyzed with a X‐ray photoelectron spectroscopy (XPS).

The two compounds possess good anti‐wear properties and excellent load‐carrying capacity. According to the XPS results, the additive reacted with counter‐face metal and generated a sulphur‐containing inorganic film consisting of FeS, FeS₂ and FeSO₄, and a complex N‐containing resin polymer film.

Their antioxidant properties are not estimated, and their anti‐wear action mechanism need to be further explored.

Two useful ashless AW lubricating oil additives were synthesized, and may be has potential as gas engine lubricating oil additives.

This paper provides a study of some N, S‐containing heterocyclic compounds as lubricating oil additives.