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This paper aims to apply the spacing effect of capacitive imaging (CI) sensors to inspect and differentiate external flaws of the protective module, internal flaws of the protective module and external flaws of the metallic module in oil and gas pipelines simultaneously. Through experimental verification, a method for differentiating three distinct kinds of flaws derived from the spacing effect of CI sensors has been demonstrated.

A 3Dimensions (3D) model for simulating the inspection of these flaws was established by using COMSOL. A novel CI sensor with adjustable working electrode spacing was designed, and a modular CI system was developed to substantiate the theoretical findings with experimental evidence. A method for differentiating three distinct kinds of flaws derived from the spacing effect of CI sensors was established.

The results indicate that the method can successfully discriminate external flaws of the protective module, internal flaws of the protective module and external flaws of the metallic module using CI sensors.

The method for differentiating three distinct kinds of flaws derived from the spacing effect of CI sensors is vital for keeping the transportation safety of oil and gas pipelines.

This study aims to design and validate a theoretical model for capacitive imaging (CI) sensors that incorporates the interelectrode shielding and surrounding shielding electrodes. Through experimental verification, the effectiveness of the theoretical model in evaluating CI sensors equipped with shielding electrodes has been demonstrated.

The study begins by incorporating the interelectrode shielding and surrounding shielding electrodes of CI sensors into the theoretical model. A method for deriving the semianalytical model is proposed, using the renormalization group method and physical model. Based on random geometric parameters of CI sensors, capacitance values are calculated using both simulation models and theoretical models. Three different types of CI sensors with varying geometric parameters are designed and manufactured for experimental testing.

The study’s results indicate that the errors of the semianalytical model for the CI sensor are predominantly below 5%, with all errors falling below 10%. This suggests that the semianalytical model, derived using the renormalization group method, effectively evaluates CI sensors equipped with shielding electrodes. The experimental results demonstrate the efficacy of the theoretical model in accurately predicting the capacitance values of the CI sensors.

The theoretical model of CI sensors is described by incorporating the interelectrode shielding and surrounding shielding electrodes into the model. This comprehensive approach allows for a more accurate evaluation of the detecting capability of CI sensors, as well as optimization of their performance.

The principal aim of this study is to investigate the relationship between technological, marketing, organizational and commercialization risk management on new product development (NPD) performance.

Based on questionnaire, the data were collected from a sample of general automotive industry in Iran. Based on theoretical considerations, a model was proposed and descriptive statistic and hierarchical regression were used to measure the relationship between risk management factors and NPD performance.

Data analysis revealed that if organization can amplify their knowledge and information about risk and main factors that affect NPD process, not only can they do their work better but can also increase their ability to predict future happenings that affect performance.

First, due to the relatively small sample size, caution should be exercised when interpreting the results. Second, the data were collected from automotive producer in Iran, which may restrict to some extent generalizability of the findings.

The results suggest that managers should consider more attention to risk management. If managers spread the risk management in all aspects of the NPD project, total performance will be increased and it can develop the probability of NPD success. Also organizations should perform great market research due to best commercialization.

Past researches have presented complete information about NPD process. But identifying and considering the effect of the risk management parameters that are connected to the NPD process were the main thrusts to perform the study. In this paper, based on past research about risk management of NPD, the extra aspect of process that can improve total performance of NPD has been examined.

This study aims to study the influence of friction influencing factors between the wire rope and the liner on the safe use of the wire rope, which can provide guidance for the reliability design of the lifting system with strong dynamic response such as high speed, heavy load, etc., and improve the friction-driven stability of the system.

In this paper, the friction mechanism of wire rope and liner under the condition of excitation is investigated by means of wire rope-liner friction-vibration experimental platform and dynamic viscoelastic test of liner.

The results show that: With increasing excitation frequency, the friction between the three liner materials (G30, K25, PU) and the wire rope decreased, and the wear of the surface shape of the liners was greater. The dynamic thermomechanical analysis (DMA) test results showed that the viscoelasticity of the three liner materials increased when the frequency was increased.

Wire ropes are widely used in deep shaft hoisting and building elevators. Its operational reliability depends on whether there is sufficient friction between the wire rope and the friction liner, and whether the friction liner has good wear resistance. The study of the friction between the wire rope and the liner influencing factors is of great significance for the safe service of the wire rope.

The related results can provide guidance for the reliability design of lifting systems with strong dynamic response, such as high speed and heavy load, to improve the friction drive stability of the system.

With the increase of mining depth, to improve the transportation efficiency of the hoist used in deep and ultra-deep mines, as well as to ensure the safety and reliability of its operation, it is crucial that the large friction hoisting equipment has sufficient friction between the wire rope and the friction lining, as well as whether the friction lining has a good abrasion resistance.

The purpose of this paper is to systematically study the dynamic contact stress, frictional heat and temperature field of femoral head-on-acetabular cup contact pairs in a gait cycle.

In this paper, four common femoral head-on-acetabular cup contact pairs are used as the research objects, mathematical calculations and finite element simulations are adopted. The contact model of hip joint head and acetabular cup was established by finite element simulation to analyze the stress and temperature distribution of the contact interface.

The results show that the contact stress of the head-on-cup interface is inversely proportional to the contact area; high contact stress directly leads to greater frictional heat. However, hip joints with metal-on-polyethylene or ceramic-on-polyethylene paired interfaces have lower frictional heat and show a significant temperature rise in one gait cycle, which may be related to the material properties of the acetabular cup.

Previous studies about calculating the interface frictional heat always ignore the dynamic change process in the contact load and the contact area. This study considered the dynamic changes of the contact stress and area of the femoral head-on-acetabular cup interface, and four common contact pairs were systematically analyzed.

The purpose of this paper is to reveal the mechanism of graphene low-temperature friction and provide a theoretical basis for the application of graphene.

A probe etching model of graphene on the copper substrate was established to obtain the friction pattern of graphene with different layers in the temperature interval from 100 to 300 K. The friction mechanism was also explained from a microscopic perspective based on thermal lubrication theory. Low-temperature friction experiments of graphene were carried out by atomic force microscopy to further verify the graphene low-temperature friction law.

Graphene nanofriction experiments were conducted at 230–300 K. Based on this, more detailed simulation studies were performed. It is found that the combined effect of thermolubricity and thermal fluctuations affects the variation of friction. For monolayer graphene, thermolubricity is the main influence, and friction decreases with increasing temperature. For multilayer graphene, thermal fluctuations gradually become the main influencing factor as the temperature rises, and the overall friction becomes larger with increasing temperature.

Graphene with excellent mechanical properties provides a new way to reduce the frictional wear of metallic materials in low-temperature environments. The friction laws and mechanisms of graphene in low-temperature environments are of great significance for the expansion of graphene application environments.

The purpose of this paper is to research whether microstructure varieties of zones at welded joints pose a tremendous effect on its corrosion in SC-CO₂.

The interrelation between the corrosion and microstructure of base metal (BM), fine grain heat affected zone (FHAZ), coarse grain heat affected zone and weld metal (WM) in welded of X80 steel in water saturated supercritical CO₂ was studied by using optical microscope, weight loss test, electrochemical measurements and surface analytical techniques.

The all subzones of X80 weld joints were attacked by SC-CO₂ corrosion and showed flower-like corrosion scale spots consisted of granular FeCO₃. The most severe corrosion appeared at WM due to lower proportion of ferrite to pearlite, but the slightest corrosion displayed at BM. GHAZ with larger grains and more polygonal ferrite exhibited more severe corrosion than that at BM. Due to its smaller grain, FHAZ displayed comparatively more severe corrosion to that at BM.

There exists close interrelation between the corrosion and microstructure of the welded carbon steel in water saturated supercritical CO₂.

Contemporary stochastic optimal control by synergy of the probability density evolution method (PDEM) and conventional optimal controller exhibits less capability to guarantee economical energy consumption versus control efficacy when non-stationary stochastic excitations drive hysteretic structures. In this regard, a novel multiscale stochastic optimal controller is invented based on the wavelet transform and the PDEM.

For a representative point, a conventional control law is decomposed into sub-control laws by deploying the multiresolution analysis. Then, the sub-control laws are classified into two generic control laws using resonant and non-resonant bands. Both frequency bands are established by employing actual natural frequency(ies) of structure, making computed efforts depend on actual structural properties and time-frequency effect of non-stationary stochastic excitations. Gain matrices in both bands are then acquired by a probabilistic criterion pertaining to system second-order statistics assessment. A multi-degree-of-freedom hysteretic structure driven by non-stationary and non-Gaussian stochastic ground accelerations is numerically studied, in which three distortion scenarios describing uncertainties in structural properties are considered.

Time-frequency-dependent gain matrices sophisticatedly address non-stationary stochastic excitations, providing efficient ways to independently suppress vibrations between resonant and non-resonant bands. Wavelet level, natural frequency(ies), and ratio of control forces in both bands influence the scheme’s outcomes. Presented approach outperforms existing approach in ensuring trade-off under uncertainty and randomness in system and excitations.

Presented control law generates control efforts relying upon resonant and non-resonant bands, and deploys actual structural properties. Cost-function weights and probabilistic criterion are promisingly developed, achieving cost-effectiveness of energy demand versus controlled structural performance.

In modern China, sports and nationalism always have close connection, and nationalism is the important reason for the promotion of Chinese sports. However, the relationship between Chinese sports and nationalism in globalised China could be much more examined by academics, as well as its influencing factors. This chapter selects the Beijing 2008 Olympic Games as the context and representative three Chinese sports heroes in the period of globalisation to study. The findings show that in some extent, Beijing 2008 Olympic Games and three Chinese sports heroes represent the national image of China in the globalised world, also bearing the burden of washing away historical humiliation and pursuing national glory. Furthermore, it is manifested that China have a complex nationalism in the process of hosting the 2008 Olympic Games. Under the influence of mass media, market economy and sports professionalisation, nationalism still exists in Chinese sports, but people gradually start to reflect on the ‘Juguo Tizhi’, the traditional Chinese sports system and the concept of ‘winning glory for the nation’. The relationship between Chinese nationalism and sports shows the important implications of rapid Chinese sports development.