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The purpose of this paper is to propose a new acceleration/deceleration (acc/dec) algorithm for motion profiles. The motion efficiency, flexibility of the motion profiles and the residual vibration of the movement are discussed in this paper.

A dynamics model is developed to assess the residual vibration of these two kinds of motion profile. And a Simulink model is created to assess the motion efficiency and flexibility of the motion profiles with the proposed acc/dec algorithm.

Considering the flexibility of trigonometric motion profiles and the higher motion efficiency of S-curve motion profiles, the authors add the polynomial parts into the jerk profile of the cosine function acc/dec algorithm to hold the jerk when it reaches the maximum so that the motion efficiency can increase and decrease residual vibration at the same time. And the cyclical parameter k shows the decisive factor for the flexibility of trigonometric motion profiles.

Comparing with the traditional motion profiles, the proposed motion profiles have higher motion efficiency and excite less residual vibration. The acc/dec algorithm proposed in this paper is useful for the present motion control and servo system.

The purpose of this paper is to enhance the accuracy as well as efficiency of high-speed machining, avoid the speed fluctuation caused by acceleration/deceleration (ACC/DEC) and increase the smoothness of feedrate in continuous corners or curves machining. The Hbot kinematic system was analyzed and combined with fused deposition modeling-based (FDM) additive manufacturing (AM) technology. Then a real-time adaptive look-ahead speed control algorithm was proposed.

To validate the performance of Hbot kinematic system and the proposed speed control algorithm, the positioning accuracy of Hbot and cross structure was compared. Also, the experimental verification was conducted among FDM based 3-D printer with cross structure as well as open source speed control algorithm (FDM with cross-OS), cross structure and the proposed speed control algorithm (FDM with cross-PS) and Hbot structure, as well as the proposed speed control algorithm (FDM with Hbot-PS), respectively.

The results indicate that the Hbot kinematic system leads to the high stability of positioning accuracy due to the small motion inertia. Furthermore, the experimental verification shows that the efficiency, printing precision and surface finish of models for FDM with Hbot-PS are obviously higher than that for FDM with cross-PS as well as FDM with cross-OS, while FDM with cross-OS shows the worst performance. The contribution of Hbot kinematic system and the proposed speed control algorithm to FDM based AM technology was validated by this work.

The Hbot kinematic system and proposed speed control algorithm have the important implication of improving the accuracy of FDM machines, especially in the low-price range segment. Also, this work can help future system developers show a possible way of tackling the motion inertia problem.

The study of Hbot kinematic system and proposed algorithm are expected to advise the current research for improving the accuracy as well as the efficiency of FDM-based AM technology.

Trajectory tracking error of robotic manipulator has limited its applications in trajectory tracking control systems. This paper aims to improve the trajectory tracking accuracy of robotic manipulator, so a linear-extended-state-observer (LESO)-based prescribed performance controller is proposed.

A prescribed performance function with the convergence rate, maximum overshoot and steady-state error is derived for the output error transformation, whose stability can guarantee trajectory tracking accuracy of the original robotic system. A LESO is designed to estimate and eliminate the total disturbance, which neither requires a detailed system model nor a heavy computation load. The stability of the system is proved via the Lyapunov theory.

Comparative experimental results show that the proposed controller can achieve better trajectory tracking accuracy than proportional-integral-differential control and linear active disturbance rejection control.

In the LESO-based prescribed performance control (PPC), the LESO was incorporated into the PPC design, it solved the problem of stabilizing the complex transformed system and avoided the costly offline identification of dynamic model and estimated and eliminated the total disturbance in real-time with light computational burden. LESO-based PPC further improved control accuracy on the basis of linear-active-disturbance-rejection-control. The new proposed method can reduce the trajectory tracking error of the robotic manipulators effectively on the basis of simplicity and stability.

The purpose of this study is to examine the role of customer experience moderating the relationship between reputation (online consumer reviews) and price premium.

This paper collected half-year period transaction of Nokia 5230XM and Kingston SD card from Taobao.com, the largest e-commerce platform in China. This paper combined theoretical analysis and empirical analysis together. Two-stage regression and logistic regression analysis was applied in this empirical analysis. The sensitivity analyses (robustness check) were also conducted in this paper.

Customer experience negatively moderates reputation price premium; thus, the positive effect of the reputation system is weaker for the experienced customer than for the naïve customer. Customers with more experience are less likely to pay the price premium and rely on a reputation system.

The results help sellers to strategize in the online marketplace. Sellers that wish to compete in the e-market must understand the type of customers they are addressing and differentiate the way they treat customers based on the level of customer experience.

This research contributes to the reputation management and customer behavior literature by identifying the effects of customer experience on the relationship between the reputation system and price premium. The results address the conflicts found in previous studies by extending the explanation of the negative reputation price premium.

The glass substrate transfer robot uses flexible arm and fork to transport the glass substrate which will generate vibration. To reduce the settling time and increase productivity, the authors proposed a vibration suppression method that integrated the continuous input shaping into the S-curve feedrate profiling.

The quasi-optimal S-curve feedrate profiling is achieved by the robot model. Then the outputs of the S-curve are shaped by the continuous input shaper, which can greatly lower the vibration and shorten the settling time.

The robot produces vibrations because of the flexibility of the belt system and the forks; the vibration of the robot is especially obvious in the acceleration and deceleration stage and the low-speed operation stage. Because the fork fingers are flexible, vibration at the end of the fork is enlarged.

The effectiveness of the proposed method is verified by the comparative experiments conducted on a glass substrate transfer robot.

Sustainable transport has become a new paradigm offering efficient, equitable, and pro-environment transport services. Many intermodal freight systems, especially those for port-to-rail networks, consist of multiple routes starting from and ending at the same port in order to exploit economies of scale. It is of interest to railway operators, therefore, to improve the efficiency of the system by finding the optimal fleet size (the number of cars assigned to a route) and frequency for each route. This paper proposes a model which determines the optimal frequency of each route under the total fleet size constraint for the one-to-many distribution. Trains carry items from one port to their destinations on their predetermined routes. This paper focuses on situations in which items from one port are transported to many destinations via railroads. The tradeoffs between transportation and inventory costs determine optimal frequency under the total fleet size and capacity constraints. The optimal frequency and fleet size of each route are calculated and then updated at the end of each step of the model. The model that we have developed in this paper is validated by port-to-rail freight data from actual shipments in Korea. The results of the analysis show that the proposed model can provide a more reliable and realistic representation of the real one-to-many distribution than the other alternatives which are commonly used. This study not only forms the theoretical basis of an effective and rational freight operation, but it also contributes to the assessment of the existing and planned logistics systems.