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This paper aims to investigate the causal inferences between mobile application adoption and changes in travelers’ purchasing behavior regarding services supported by the travel and tourism industry.

Using a quasi-experiment conducted by an airline, data sets from more than 10,000 travelers were collected, and hypotheses were tested using propensity score matching and difference-in-difference methods.

Mobile application adoption has a significant positive effect on the total purchasing frequency of services and a significant adverse effect on booking tickets in advance and purchasing frequency from self-owned websites. Besides, this finding also suggested that members or travelers who had high average purchases in the past tend to buy more air tickets on average after mobile application adoption, while the number of days to book tickets in advance and purchase auxiliary services declined after mobile application adoption. However, males purchased more auxiliary services via mobile applications.

The study is based on the causal effect of mobile application adoption on purchasing behavior. Nevertheless, the theoretical basis remains relatively weak. Furthermore, the underlying mechanisms that cause the changes in purchasing behavior via mobile applications need to be elucidated.

This study enriches the hospitality and tourism literature on mobile application adoptions, multichannel purchasing behavior and revenue management. First, a quasi-experimental design is used to verify a causal relationship between mobile applications’ adoption and travelers’ purchasing behavior in the travel and tourism industry. Second, this study adds to examining travelers’ multichannel purchasing behavior in the travel and tourism industry. Third, this work enriches the current literature that explores auxiliary services and revenue management in the travel industry.

Mobile application adoption significantly impacted the travel and tourism industry. Besides, To the best of the authors’ knowledge, this is one of the first empirical studies that examined changes in purchasing behavior due to mobile application adoption from the perspective of service type. The findings provide the first evidence of the impact of mobile application adoption on service purchasing in the travel industry.

This paper aims to improve calibration and force measurement accuracy of multi-sensors’ piezoelectric dynamometer used in thrust measurement of rocket/air vehicle engine.

This paper presents a mapping solution method of sensors’ outputs based on the Kirchhoff thin plate theory, builds force-deformation differential equations with specific boundary conditions, uses finite difference (FD) method to solve the equations and analyzes outputs in offset loading forces in four-sensor square layout in main direction. The resultant force deviations calculated by the Kirchhoff theory are optimized with sequence quadratic program (SQP) method, and a calibration method of multiple loading points (MLP) based on the Kirchhoff theory is presented. Experiments of static calibration and verification are complemented to contrast the novel and single loading point (SLP) calibration method.

Experiments of static calibration and its verification show that at a loading force of 5,000N, the average resultant force deviations with MLP is 17.87N (0.35% FS) compared with single loading point method 26.45N (0.53% FS), improving calibration and measurement precision.

A novel calibration method with MLP is presented. Force distributions of multiple sensors of main direction in piezoelectric dynamometer with offset loading force are solved with the Kirchhoff theory. The resultant force deviations calculated by Kirchhoff theory are optimized with the SQP method.

The purpose of this paper is to achieve the trajectory tracking measurement of a moving target based on double position sensitive detectors (PSDs).

In this paper, first, a double PSD-based measurement system including hardware system and software system is built up. Then, the working principle is studied to calculate parameters, and calibration experience is conducted. Finally, this double PSD-based measurement system is used to test angular displacement and axial displacement on the tool magazine and automatic tool changer.

In the experiment, the maximum position error of a space point based on double PSD measurement system is 0.8566 mm, and the average error is 0.4716 mm. These results show that the built double PSD-based measurement system of trajectory tracking of a moving target is reasonable.

Combining the characteristics of the PSD and principles of binocular visual measurement, a non-contact three-dimensional measuring system based on double PSDs is developed. The designed double-based measurement system is quite suitable for measurement of a fast-changing illuminant or in the case that the tracking accuracy is not tight.

The jet impingement usually accompanying large interface movement is studied by the in-house solver MLParticle-SJTU based on the modified moving particle semi-implicit (MPS) method, which can provide more accurate pressure fields and deformed interface shape. The comparisons of the pressure distribution and the shape of free surface between the presented numerical results and the analytical solution are investigated. The paper aims to discuss these issues.

To avoid the instability in traditional MPS, a modified MPS method is employed, which include mixed source term for Poisson pressure equation (PPE), kernel function without singularity, momentum conservative gradient model and highly precise free surface detection approach. Detailed analysis on improved schemes in the modified MPS is carried out. In particular, three kinds of source term in PPE are considered, including: particle number density (PND) method, mixed source term method and divergence-free method. Two typical kernel functions containing original kernel function with singularity and modified kernel function without singularity are analyzed. Three kinds of pressure gradient are considered: original pressure gradient (OPG), conservative pressure gradient (CPG) and modified pressure gradient (MPG). In addition, particle convergence is performed by running the simulation with various spatial resolutions. Finally, the comparison of the pressure fields by the modified MPS and by SPH is presented.

The modified MPS method can provide a reliable pressure distribution and the shape of the free surface compared to the analytical solution in a steady state after the water jet impinging on the wall. Specifically, mixed source term in PPE can give a reasonable profile of the shape of free surface and pressure distribution, while PND method adopted in the traditional MPS is not stable in simulation, and divergence-free method cannot produce rational pressure field near the wall. Two kernel functions show similar pressure field, however, the kernel function without singularity is preferred in this case to predict the profile of free surface and pressure on the wall. The shape of free surface by CPG and MPG is agreement with the analytical solution, while a great discrepancy can be observed by OPG. The pressure peak by MPG is closer to the analytical solution than that by CPG, while the pressure distribution on the right hand side of the pressure peak by latter is better match with the analytical solution than that by former. Besides, fine spatial resolution is necessary to achieve a good agreement with analytical results. In addition, the pressure field by the modified MPS is also quite similar to that by SPH, and this can further validate the reliable of current modified MPS.

The present modified MPS appears to be a stable and reliable tool to deal with the impinging jet flow problems involving large interface movement. Mixed source term in PPE is superior to PND adopted in the traditional MPS and divergence-free method. The kernel function without singularity is preferred to improve the computational accuracy in this case. CPG is a good choice to obtain the shape of free surface and the pressure distribution by jet impingement.

The corrosion of buried steel pipelines is becoming more serious because of stress corrosion, stray current corrosion and other reasons. This paper aims to study the various alternating current (AC) interference densities on the stress corrosion cracking behaviors of X80 steel samples under cathodic protection (CP) in the simulated soil electrolyte environment by using an electrochemical method.

The change of corrosion rate and surface morphology of the X80 steel samples at various AC current densities from 0 to 150 A/m² or CP potential between −750 and −1,200 mV in the soil-simulating environment was revealed by the electrochemical methods and slow strain rate testing methods.

The results revealed that with the increase of interference density, the corrosion potential of the X80 steel samples shifted to the negative side, and the corrosion pitting was observed on the surface of the sample, this may cause a danger of energy leak. Moreover, the corrosion rate was found to follow a corresponding change with the stress–strain curve. Besides, with the introduction of the CP system, the corrosion rate of the X80 steel working electrode decreased at a low cathodic potential, while showed an opposite behavior at high cathodic potential. In this study, the correlation between AC stray current, cathodic potential and stress was established, which is beneficial to the protection of oil and gas pipeline.

Investigation results are of benefit to provide a new CP strategy under the interference of AC stray current corrosion and stress corrosion to reduce the corrosion rate of buried pipelines and improve the safety of pipeline transportation.

The purpose of this paper is to analyze the influence of particle motion on the lubrication characteristics. The dynamics of the particle in the lubricant is also studied.

The dynamics of the particle is studied using Newton's second law. The particle dynamic equation is solved to determine the particle velocity, angular velocity, and location. The modified Reynolds equation is solved in couple with particle motion to determine the film pressure and velocity.

The motion of a particle suspended in the lube oil is clarified. The initial relative velocity between the particle and the fluid has a significant effect on the lubrication. For the same particle location and velocity, the larger particle or the closer distance between particle center and lower plate has greater effects on the film pressure.

The influence of the particle geometry on the lubrication is neglected in the study because of the small size of the particle, this neglect is idealized. Further study will take the effects of the particle geometry into consideration.

The paper provides the motion of the particle in the lubricant, and the modified Reynolds equation considering the particle translation as well as rotation is derived.

This study aims to explore the relative importance of the subdimensions of total rewards satisfaction in predicting research and development (R&D) employee creativity. In addition, the study examines the indirect effects of the subdimensions of total rewards satisfaction on creativity via work engagement and the moderating role of challenge-related work stress in the first stage.

A two-wave design was used, in which total rewards satisfaction and challenge-related work stress were measured in the first wave. Work engagement and creativity were measured in the second wave. Dominance analysis and the latent moderated mediation model were used for the data analyses.

The analyses show that nonfinancial rewards satisfaction completely dominates indirect and direct financial rewards satisfaction when predicting creativity. Indirect financial rewards satisfaction completely dominates direct financial rewards satisfaction when predicting creativity. Work engagement mediates the relationships between the subdimensions of total rewards satisfaction and creativity. Challenge-related work stress moderates the relationships between the subdimensions of total rewards satisfaction and work engagement and the indirect effects of the subdimensions of total rewards satisfaction on creativity via work engagement.

The results imply that managers should set challenge demands for R&D employees and try to improve their total rewards satisfaction, especially their nonfinancial and indirect financial rewards satisfaction, for them to be more creative.

This empirical study contributes to the literature by comparing the relative importance of the different dimensions of total rewards satisfaction in predicting creativity. The study also clarifies how (through work engagement) and when (based on challenge-related work stress) the subdimensions of total rewards satisfaction are positively related to R&D employees' creativity.

Organizations can greatly benefit from the transfer of knowledge from older employees to younger generations. However, older workers often hesitate to share their expertise with their younger colleagues. Grounded in conservation of resources theory and the stereotype threat framework, this study aims at examining the negative impact of age-based stereotype threat on organizational knowledge management.

The authors developed a moderated mediation model and collected data from 219 older workers with a time-lagged design to explore the effect of age-based stereotype threat on older workers’ knowledge hiding.

The results showed that age-based stereotype threat could lead to knowledge hiding behaviors among older workers due to increased job insecurity, and leader-member exchange can potentially mitigate these effects.

The findings underscore the detrimental effect of age-based stereotype threat on organizational knowledge management and suggest that organizations should foster an age-inclusive environment to facilitate effective intergenerational knowledge transfer.

Class imbalance learning, which exists in many domain problem datasets, is an important research topic in data mining and machine learning. One-class classification techniques, which aim to identify anomalies as the minority class from the normal data as the majority class, are one representative solution for class imbalanced datasets. Since one-class classifiers are trained using only normal data to create a decision boundary for later anomaly detection, the quality of the training set, i.e. the majority class, is one key factor that affects the performance of one-class classifiers.

In this paper, we focus on two data cleaning or preprocessing methods to address class imbalanced datasets. The first method examines whether performing instance selection to remove some noisy data from the majority class can improve the performance of one-class classifiers. The second method combines instance selection and missing value imputation, where the latter is used to handle incomplete datasets that contain missing values.

The experimental results are based on 44 class imbalanced datasets; three instance selection algorithms, including IB3, DROP3 and the GA, the CART decision tree for missing value imputation, and three one-class classifiers, which include OCSVM, IFOREST and LOF, show that if the instance selection algorithm is carefully chosen, performing this step could improve the quality of the training data, which makes one-class classifiers outperform the baselines without instance selection. Moreover, when class imbalanced datasets contain some missing values, combining missing value imputation and instance selection, regardless of which step is first performed, can maintain similar data quality as datasets without missing values.

The novelty of this paper is to investigate the effect of performing instance selection on the performance of one-class classifiers, which has never been done before. Moreover, this study is the first attempt to consider the scenario of missing values that exist in the training set for training one-class classifiers. In this case, performing missing value imputation and instance selection with different orders are compared.

The purpose of this paper is to provide an integrated semantic information retrieval (IR) solution based on an ontology-improved vector space model for situations where a digital collection is established or curated. It aims to create a retrieval approach which could return the results by meanings rather than by keywords.

In this paper, the authors propose a semantic term frequency algorithm to create a semantic vector space model (SeVSM) based on ontology. To support the calculation, a multi-branches tree model is created to represent the ontology and a set of algorithms is developed to operate it. Then, a semantic ontology-based IR system based on the SeVSM model is designed and developed to verify the effectiveness of the proposed model.

The experimental study using 30 queries from 15 different domains confirms the effectiveness of the SeVSM and the usability of the proposed system. The results demonstrate that the proposed model and system can be a significant exploration to enhance IR in specific domains, such as a digital library and e-commerce.

This research not only creates a semantic retrieval model, but also provides the application approach via designing and developing a semantic retrieval system based on the model. Comparing with most of the current related research, the proposed research studies the whole process of realizing a semantic retrieval.