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The purpose of this paper is to investigate the corrosion behaviors of 2A12 aluminum alloy in NaCl and EXCO solution, and establish the relationship between the corrosion depth and the time.

Alternate immersion corrosion test chamber was used to perform the corrosion test. The corrosion mediums were 3.5 percent NaCl solution and EXCO solution (NaCl 234 g/L, KNO3 50 g/L, 68 percent HNO3 6.8 mL/L). The surface morphology was studied using the digital microscope.

The average corrosion rate of aluminum alloy in NaCl solution decreased gradually at the initial stage and then went to a plateau value. The average corrosion rate of aluminum alloy in EXCO solution increased first, then showed a downward trend. The empirical function D=At B was verified.

The results could provide a reference for the establishment of accelerated environmental spectrum in the laboratory and give instructions on the application of aluminum alloy in alternated dry and wet environment.

Bankruptcy is a financial failure of a business or an organization. Different kinds of bankruptcy prediction techniques are proposed to predict it. But, they are restricted as techniques in predicting the bankruptcy and not addressing the associated activities like acquiring the suitable data and delivering the results to the user after processing it. This situation demands to look for a comprehensive solution for predicting bankruptcy with intelligence. The paper aims to discuss these issues.

To model Business Intelligence (BI) solution for BP the concept of reference model is used. A Reference Model for Business Intelligence to Predict Bankruptcy (RMBIPB) is designed by applying unit operations as hierarchical structure with abstract components. The layers of RMBIPB are constructed from the hierarchical structure of the model and the components, which are part of the reference model. In this model, each layer is designed based on the functional requirements of the Business Intelligence System (BIS).

This reference model exhibits the non functional software qualities intended for the appropriate unit operations. It has flexible design in which techniques are selected with minimal effort to conduct the bankruptcy prediction. The same reference model for another domain can be implemented with different kinds of techniques for bankruptcy prediction.

This model is designed using unit operations and the software qualities exhibited by RMBIPB are limited by unit operations. The data set which is applied in RMBIPB is limited to Indian banks.

A comprehensive bankruptcy prediction model using BI with customized reporting.

Organizations in many domains generate a considerable amount of heterogeneous data every day. Such data can be processed to enhance these organizations’ decisions in real time. However, storing and processing large and varied datasets (known as big data) is challenging to do in real time. In machine learning, streaming feature selection has always been considered a superior technique for selecting the relevant subset features from highly dimensional data and thus reducing learning complexity. In the relevant literature, streaming feature selection refers to the features that arrive consecutively over time; despite a lack of exact figure on the number of features, numbers of instances are well-established. Many scholars in the field have proposed streaming-feature-selection algorithms in attempts to find the proper solution to this problem. This paper presents an exhaustive and methodological introduction of these techniques. This study provides a review of the traditional feature-selection algorithms and then scrutinizes the current algorithms that use streaming feature selection to determine their strengths and weaknesses. The survey also sheds light on the ongoing challenges in big-data research.

The set-union knapsack problem is one of the most significant generalizations of the Non-deterministic Polynomial (NP)-hard 0-1 knapsack problem in combinatorial optimization, which has rich application scenarios. Although some researchers performed effective algorithms on normal-sized instances, the authors found these methods deteriorated rapidly as the scale became larger. Therefore, the authors design an efficient yet effective algorithm to solve this large-scale optimization problem, making it applicable to real-world cases under the era of big data.

The authors develop three targeted strategies and adjust them into the adaptive tabu search framework. Specifically, the dynamic item scoring tries to select proper items into the knapsack dynamically to enhance the intensification, while the age-guided perturbation places more emphasis on the diversification of the algorithm. The lightweight neighborhood updating simplifies the neighborhood operators to reduce the algorithm complexity distinctly as well as maintains potential solutions. The authors conduct comparative experiments against currently best solvers to show the performance of the proposed algorithm.

Statistical experiments show that the proposed algorithm can find 18 out of 24 better solutions than other algorithms. For the remaining six instances on which the competitor also achieves the same solutions, ours performs more stably due to its narrow gap between best and mean value. Besides, the convergence time is also verified efficiency against other algorithms.

The authors present the first implementation of heuristic algorithm for solving large-scale set-union knapsack problem and achieve the best results. Also, the authors provide the benchmarks on the website for the first time.

The purpose of this study is to theoretically discuss and empirically test the mediating effect of emotional exhaustion (EE) and the moderating effects of perceived coworker support (PCS) and positive affectivity (PA) in the relationship between abusive supervision (AS) and knowledge hiding (KH).

The authors adopted a three-wave survey to collect data from eight high-tech companies in north China. The final sample of 209 available responses was analyzed with hierarchical regression analyses and bias-corrected bootstrapping methods.

AS positively affected employees’ KH. EE fully mediated this positive relationship. PCS and PA attenuated the relationship between AS and EE, respectively, and the mediating effects of EE.

First, the study contributes to the knowledge management and leadership literature by examining the relationship between the following two dysfunctional workplace behaviors: AS and KH. Second, the authors explicitly tested the underlying psychological mechanism in the above relationship. Third, this study specified two ways – obtaining support from coworkers and generating positive emotions – to attenuate the toxic effects of AS on victims.

Continuum manipulators are often used in complex and narrow space in recent years because of their flexibility and safety. Vision is considered to be one of the most direct methods to obtain its spatial shape. However, with the improvement of the cooperation requirements of multiple continuum manipulators and the increase of space limitation, it is impossible to obtain the complete spatial shape information of multiple continuum manipulators only by several cameras.

This paper proposes a fusion method using inertial navigation sensors and cameras to reconstruct the shape of continuum manipulators in the whole workspace. The camera is used to obtain the position information, and the inertial navigation sensor is used to obtain the attitude information. Based on the above two information, the shape of the continuum manipulator is reconstructed by fitting Bézier curve.

The experiment result of single continuum manipulator shows that the cubic Bézier curves is applicable to curve fitting of variable curvature, the maximum fitting error is about 2 mm. Meanwhile, the experiment result shows that this method is not affected by obstacles and can still reconstruct the shape of the continuum manipulators in 3-D space by detecting the position and attitude information of the end.

According to the authors’ knowledge, this is the first study on spatial shape reconstruction of multiple continuum manipulators and the first study to introduce inertial navigation sensors and cameras into the field of shape reconstruction of multiple continuum manipulators in narrow space. This method is suitable for shape reconstruction of manipulator with variable curvature continuum manipulator. When the vision of multiple continuum manipulators is blocked by obstacles, the spatial shape can still be reconstructed only by exposing the end point. The structure is simple, but it has certain accuracy within a certain range.

The computing power of the legged robot is not enough to perform high-frequency updates for the full-body model predictive control (MPC) of the robot, which is a common problem encountered in the gait research of the legged robot. The purpose of this paper is to propose a high-frequency MPC control method for the bounding gait of a parallel quadruped robot.

According to the bounding gait characteristics of the robot, the quadruped robot model is simplified to an equivalent plane bipedal model. Under the biped robot model, the forces between the robot’s feet and the ground are calculated by MPC. Then, the authors apply a proportional differential controller to distribute these forces to the four feet of the quadruped robot. The robot video can be seen at www.bilibili.com/video/BV1je4y1S7Rn.

To verify the feasibility of the controller, a prototype was made, and the controller was deployed on the actual prototype and then fully analyzed through experiments. Experiments show that the update frequency of MPC could be stabilized at 500 Hz while the robot was running in the bounding gait stably and efficiently.

This paper proposes a high-frequency MPC controller under the simplified model, which has a higher working efficiency and more stable control performance.

Due to fierce competition in the mobile retailing market, it is desirable to identify the success factors driving consumers to reuse a mobile shopping application. This research intends to develop a model for mobile shopping app success by integrating an e-commerce systems success (ESS) model and sales promotion benefits and parasocial interaction literatures.

302 useable online questionnaires were obtained. The data analysis was conducted using the structural equation modelling.

The results indicate the validity of the ESS model in predicting consumers' reuse intention of mobile shopping apps where three quality dimensions of system, information and service facilitate both perceived value and user satisfaction, which in turn generates reuse intention. Furthermore, savings and entertainment denoting the utilitarian and hedonic sales promotion benefits have positive impact on perceived value but have no influence on satisfaction. Parasocial intention between consumers and sellers facilitates both value perception and satisfaction.

This research contributes to the mobile retailing literature by identifying the success factors driving consumers' continuance intention of mobile shopping apps. Theoretically, it validates and extends the ESS model in mobile shopping app context by identifying savings, entertainment and parasocial interaction as additional success factors. Based on the findings, two approaches are proposed to suggest mobile retailers design a successful mobile shopping app.

The purpose of this study is to test the mechanism of visionary leadership on subordinates' work withdrawal behavior through cognitive strain and psychological contract violation, and also to reveal the possible dark side of visionary leadership. The moderation effects of subordinates' facades of conformity and leader behavioral integrity in the cognition–affect dual-path process are also discussed.

This study conducted a three-wave longitudinal survey. The data were collected from 574 employees and their superiors in several Chinese enterprises. The authors used Mplus 7.4 and adopted a bootstrapping technique in the data analysis.

Visionary leadership has positive effects on cognitive strain and psychological contract violation; cognitive strain and psychological contract violation mediate the relationship between visionary leadership and work withdrawal behavior, respectively. Subordinates' facades of conformity and leader behavioral integrity moderate the positive effects of visionary leadership on cognitive strain and psychological contract violation, as well as the indirect effect of visionary leadership on subordinates' work withdrawal behavior through cognitive strain and psychological contract violation.

This study reveals the underlying mechanism of visionary leadership's negative impact on job outcome through the cognition and affective reaction of subordinates to visionary leadership, and broadens the scope of visionary leadership research. It also provides some practical suggestions on how to transmit the organizational vision effectively and reduce subordinates' work withdrawal behavior.