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In practical engineering, oil filters often work under asymmetric cyclic loading. In order to improve the prediction accuracy of fatigue life of the oil filters under asymmetric cyclic loading, the effect of strain ratio and low cycle fatigue plastic deformation on fatigue life need to be considered. This paper aims to discuss the aforementioned objective.

First, strain-controlled fatigue tests with strain ratios of 0, 0.5 and −1 were carried out on the oil filter material 2A70-T6 aluminum alloy, and the test data were used to obtain strain fatigue life curves at three strain ratios. Then, based on the idea of the constant life curve method, the average value of the ratio of the strain amplitude corresponding to different strain ratios under the same partial life was defined as the strain ratio factor. Finally, the elastic-plastic factor was modified by the strain ratio factor, and a new fatigue life prediction model considering the effect of strain ratio was proposed.

The proposed model was validated, respectively, by fatigue test data of 2A70-T6 aluminum alloy, 2124-T851 aluminum alloy and oil filter and the results of the proposed model were compared with the Coffin–Manson equation, Morrow model and Smith–Watson–Topper (SWT) model, showing that the proposed model had higher applicability and accuracy.

In this work, a strain ratio factor is established based on the idea of the constant life curve method, and the strain ratio factor is used to modify the introduced elastic-plastic factor, and then a new fatigue life prediction model considering the influence of strain ratio and low cycle fatigue plastic deformation on material fatigue damage accumulation is proposed. The results show that the prediction results of the proposed model are in good agreement with the experimental data, and the proposed model has good fatigue life prediction ability considering the influence of strain ratio and lays a foundation for the fatigue life prediction of the oil filter.

The stress state near the notch affects fatigue damage directly, but quantifying the stress field is difficult. The purpose of this study is to provide a mathematical description method of the stress field near the notch to achieve a reliable assessment of the fatigue life of notched specimens.

Firstly, the stress distribution of notched specimens of different materials and shapes under different stress levels is investigated, and a method for calculating the stress gradient impact factor is presented. Then, the newly defined stress gradient impact factor is used to describe the stress field near the notch, and an expression for the stress at any point along a specified path is developed. Furthermore, by combining the mathematical expressions for the stress field near the notch, a multiaxial fatigue life prediction model for notched shaft specimens is established based on the damage mechanics theory and closed solution method.

The stress gradient factor for notched specimens with higher stress concentration factors (V60-notch, V90-notch) varies to a certain extent when the external load and material change, but for notched specimens with relatively lower stress concentration factors (C-notch, U-notch, stepped shaft), the stress gradient factor hardly varies with the change in load and material, indicating that the shape of the notch has a greater influence on the stress gradient. It is also found that the effect of size on the stress gradient factor is not obvious for notched specimens with different shapes, there is an obvious positive correlation between the normal stress gradient factor and the normal stress concentration factor compared with the relationship between the shear stress gradient factor and the stress concentration factor. Moreover, the predicted results of the proposed model are in better agreement with the experimental results of five kinds of materials compared with the FS model, the SWT model, and the Manson–Coffin equation.

In this paper, a new stress gradient factor is defined based on the stress distribution of a smooth specimen. Then, a mathematical description of the stress field near the notch is provided, which contains the nominal stress, notch size, and stress concentration factor which is calculated by the finite element method (FEM). In addition, a multiaxial fatigue life prediction model for shaft specimens with different notch shapes is established with the newly established expressions based on the theory of damage mechanics and the closed solution method.

With the continuous increase of users, resources and tags, social tagging systems gradually present the characteristics of “big data” such as large number, fast growth, complexity and unreliable quality, which greatly increases the complexity of recommendation. The contradiction between the efficiency and effectiveness of recommendation service in social tagging is increasingly becoming prominent. The purpose of this study is to incorporate topic optimization into collaborative filtering to enhance both the effectiveness and the efficiency of personalized recommendations for social tagging.

Combining the idea of optimization before service, this paper presents an approach that incorporates topic optimization into collaborative recommendations for social tagging. In the proposed approach, the recommendation process is divided into two phases of offline topic optimization and online recommendation service to achieve high-quality and efficient personalized recommendation services. In the offline phase, the tags' topic model is constructed and then used to optimize the latent preference of users and the latent affiliation of resources on topics.

Experimental evaluation shows that the proposed approach improves both precision and recall of recommendations, as well as enhances the efficiency of online recommendations compared with the three baseline approaches. The proposed topic optimization–incorporated collaborative recommendation approach can achieve the improvement of both effectiveness and efficiency for the recommendation in social tagging.

With the support of the proposed approach, personalized recommendation in social tagging with high quality and efficiency can be achieved.

As a multinational corporation (MNC) implements a new innovation campaign at its worldwide operations, varying degrees of success stories are reported. The extent of how an innovation campaign and methodology can be transferred from its corporate office to its overseas operations has been the subject of considerable debate. Implementing an innovation methodology such as the total quality management (TQM) can be challenged by the organizational culture unique to each operation. The purpose of this paper is to investigate the relationship between organizational culture stemming from national culture and TQM implementation performance.

In total, 186 managers of MNCs are surveyed in their cultural orientations and TQM implementation experiences. The survey result is analyzed by regressing cultural elements on TQM elements.

Our result suggests that an organization's TQM practices are significantly influenced by the organization culture. However, each dimension of organization culture is related to TQM in different fashions. For instance, power distance influences all the TQM elements, but masculinity has positive impact on business performance of TQM practice only.

Our findings may assist MNCs in explaining varying success stories of quality management implementation efforts. Furthermore, MNCs can focus their efforts towards improving certain organizational culture that is more significantly related to a certain quality management element.

No previous research has reported on how organizational culture stemming from national culture affects quality management methodology implementation.

The purpose of this paper is to establish an accurate model to quantify the effect of conductor roughness on insertion loss (IL) and provide improved measurements and suggestions for manufacturing good conductive copper lines of printed circuit board.

To practically investigates the modified model of conductor roughness, three different kinds of alternate oxidation treatments were used to provide transmission lines with different roughness. The IL results were measured by a vector net analyzer for comparisons with the modified model results.

An accurate model, with only a 1.8% deviation on average from the measured values, is established. Compared with other models, the modified model is more reliable in industrial manufacturing.

This paper introduces the influence of tiny roughness structures on IL. Besides, this paper discusses the effect of current distribution on IL.

The color painting of ancient buildings has high historical and artistic value but is prone to aging due to long-term outdoor exposure. The purpose of this study is to develop a new type of sealing coating to mitigate the impact of ultraviolet (UV) light on color painting.

The new coating was subjected to a 500-h UV-aging test. Compared with the existing acrylic resin Primal AC33, the UV aging behavior of the new coating, such as color difference and gloss, was studied with aging time. The Fourier infrared spectra of the coatings were analyzed after the UV-aging test.

Compared with AC33, the antiaging performance of SF8 was substantially improved. SF8 has a lower color difference value and better light retention and hydrophobicity. The Fourier transform infrared spectroscopy results showed that the C-F bond and Si-O bonds in the resin of the optimized sealing coating protected the main chain C-C structure from degradation during the aging process; thus, the resin maintained good stability. The hindered amine light stabilizer TN292 added to the coating inhibited the antiaging process by trapping active free radicals.

To address the problem of UV aging of oil-decorated colored paintings, a new type of sealing coating with excellent antiaging properties was developed, laying the foundation for its demonstration application on the surface of ancient buildings.

The authors position security measures and payment culture as key determinants of perceived security (PS) and trust. The purpose of this paper is to empirically investigate how PS and trust affect users’ attitude toward mobile payment use and why mobile payment has developed differently in the USA and in China.

Empirical data were collected from a survey conducted both in China and in the USA. The whole sample consists of 186 Chinese and 196 Americans. Partial least squares analysis was conducted to test the proposed relationships and multigroup comparison analysis was performed to examine the differences in the coefficients of those relationships between Chinese and the US model.

The findings show that payment culture (measured by coverage of mobile payment context (CMPC) and uncertainty avoidance (UA)) and security measures (measured by security technology protection (STP), security rules and policies (SRP), and security responsibility commitment (SRC)) have significantly positive impacts on the PS and trust, except that the positive impact of security on trust is not supported. The impacts of CMPC and PS on trust in the USA are significantly smaller than those in China, whereas the impacts of security measures and UA on PS and trust do not show significant differences between the two countries.

Respondents of this study are selected from young educated population, the major users of mobile payment in 2015. However, recently with the increasing penetration of mobile payment, major mobile payment users are not only limited to young educated population, and thus there may be new findings after extending the range of respondents’ age. Since the research subjects in this study are the mobile payment of China and the USA, the authors could also expect different findings when the research subjects are extended or changed to other countries because of different mobile payment cultures across countries.

Findings in this paper will help mobile payment service providers to know the determinants of their users’ behavior intention and to take measures to improve these determinants, and these findings can also provide mobile payment service providers with insights into the differences in mobile payment use between the two countries and suggestions of measures that they can take to increase users’ attitude toward mobile payment use. Furthermore, the findings of this paper also help these providers globalize efficiently by paying more attention to those antecedents.

The findings in this paper show that there is no difference in the impacts of UA and security measures on PS and trust between China and the USA. However, the impacts of PS and CMPC on trust in China are significantly higher than those in the USA. This is because that globalization has made people from different countries hold similar UA, whereas the CMPC, a construct refers to the business environment of mobile payment, is still very different between China and the USA.

This study extends prior studies of attitude toward mobile payment use through proposing that security measures and payment culture are key determinants of PS and trust and examining the role of PS and trust on the attitude. Furthermore, the empirical findings will not only provide mobile payment service providers with important insights into the differences in mobile payment adoption between the two countries, but also help these providers globalize efficiently by paying more attention to those antecedents.

Biometric systems are widely used for face recognition. They have rapidly developed in recent years. Compared with other approaches, such as fingerprint recognition, handwriting verification and retinal and iris scanning, face recognition is more straightforward, user friendly and extensively used. The aforementioned approaches, including face recognition, are vulnerable to malicious attacks by impostors; in such cases, face liveness detection comes in handy to ensure both accuracy and robustness. Liveness is an important feature that reflects physiological signs and differentiates artificial from real biometric traits. This paper aims to provide a simple path for the future development of more robust and accurate liveness detection approaches.

This paper discusses about introduction to the face biometric system, liveness detection in face recognition system and comparisons between the different discussed works of existing measures.

This paper presents an overview, comparison and discussion of proposed face liveness detection methods to provide a reference for the future development of more robust and accurate liveness detection approaches.

The purpose of this paper is to measure the high-quality development level of China's marine economy and analyze corresponding spatial and temporal distribution characteristic.

Design and optimize the index system of high-quality development level of marine economy and use entropy and TOPSIS method for comprehensive evaluation.

The research finds that from 2017 to 2019, the high-quality development tendency of China's marine economy is on the rise, but the overall level is still low. The level of each subsystem has different distribution characteristics in different provinces and cities. Guangdong, Shandong and Shanghai have a high comprehensive level. According to the comprehensive level of high-quality development of marine economy, 11 coastal provinces are divided into three types: leading, general and backward.

This paper clarifies the temporal and spatial distribution law of high-quality development level of China's marine economy, providing basis for promoting comprehensive and coordinated improvement of coastal provinces and cities.

An indicator system for the high-quality development level of the marine economy has been established, including social development guarantee, marine economic foundation, marine science and technology drive and green marine sustainability.