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This research examines the effects of input price discrimination on allocation efficiency and social welfare. Instead of assuming constant marginal costs, we allow downstream firms to produce under increasing marginal costs. When downstream firms operate in separate markets, even though total output remains unchanged, consumer surplus and social welfare could be greater under discriminatory pricing than under uniform pricing. Moreover, the social desirability of input price discrimination can still hold true when downstream firms compete either in Cournot or Bertrand fashion.

In this paper, a Lyapunov-based fuzzy logic control (FLC) system is developed for controlling of complicated as well as distinct nonlinear systems. According to Lyapunov Stability Theory, a candidate Lyapunov function with simple quadratic form is designed. Via constructing the fuzzy IF–THEN rules through referencing the statuses of errors states and error derivatives in each sub-space of the Lyapunov function derivatives, the proposed structure of FLC system is able to appropriately as well as flexibly adjust the control forces with minimum magnitude compensating the nonlinear systems in real-time. In addition, the designed FLC system can be applied to different kinds of control systems without further information and operation experience. Two nonlinear systems with distinct structures, classical Lorentz system and Mathieu-van der Pol system, are illustrated for simulation examples. In comparison of the previous research work, the simulation results reveal the effectiveness, flexibility and convenient-design of the proposed method.

Motion trajectory commands are usually generated using CAD/CAM software and a specified motion controller. At the CAD/CAM stage, the motion commands are generated with respect to the constrains on the contouring error and the application. These commands are also related to the motion controller, which incorporates an advanced blending interpolation method in its function core. Although, high-speed motion can be achieved using blending interpolation, the accuracy of the trajectory is decreased. This study proposes a new blending method that uses a predefined absolute accuracy to optimize both the speed and the accuracy of the generated motion trajectory. The proposed method uses two strategies: the first accelerates or decelerates the velocity profile and the second inserts an arc trajectory command and the corresponding blending accuracy in a critical segment, in order to achieve the speed and the contouring error that is predefined by the user. Four cases are used to determine the performance of the proposed method: (a) line-to-line, (b) line-to-arc, (c) arc-to-arc, and (d) arc-to-line interpolations. The experiments use a predefined speed and accuracy for the motion trajectory. The results demonstrate that the proposed motion trajectory planning process satisfies the needs of industrial applications such as laser cutting and dispensing.

In the implementation of robot motion control, it often requires complex forward and inverse kinematics calculation. However, this algorithm requires more CPU time in the software realization and apparently affects the response of robot movement. To solve this problem, the work is aimed at the development of the forward and inverse kinematics IP (intellectual property) based on FPGA (field programmable gate array) implementation and hoped to complete the overall computation less than ten microseconds for the purpose of enhancing the performance of the robot movement. In this paper, firstly, the forward and inverse kinematics for SCARA robot is derived. Secondly the circuit behavior using VHDL (Very-High-Speed-IC Hardware Description Language) is described. The design of VHDL code will apply the parameterized function to increase the code flexible and the FSM (Finite state machine) strategy is used to reduce the hardware resource usage. To verify the correctness of the proposed forward and inverse kinematics IP, a co-simulation work is constructed by ModelSim and Simulink. The forward and inverse kinematics IP is run by ModelSim and the Simulink models is taken as a test bench that generates stimulus to ModelSim and displays the output response. Finally, the developed forward and inverse kinematics IP will be downloaded to FPGA to further confirm its effectiveness.

In this paper, we propose an efficient algorithm based on the anisotropic diffusion model to detect defect in a low-contrast surface image, especially aimed at anti-reflective (AR) glass. The proposed algorithm has two important procedures: (1) a modified anisotropic diffusion model and (2) morphological directivity filter. The modified diffusion model based on an adaptive edge threshold, the standard score (Z-score), is proposed to quickly and efficiently enhance the low-contrast defects. It acts as the adaptive enhancement process. The pixels with both the low gradient and the high Z-score or the high gradient and the low Z-score will generate a high diffusion coefficient. It enhances the gray levels of suspected defective edges and also preserves the original gray levels of an internal area of suspected defects, as well as generates the slight smoothing process for the noisy background. A simple and efficient method can easily segment the defects, followed by the effective morphological directivity filter, which removes noise from the thresholding image. The proposed algorithm is evaluated by a set of 23 low-contrast surface images of AR glass in this study. The experimental results show that the proposed algorithm is superior to the four competitive approaches. The defect detection results demonstrate that the proposed algorithm can segment the complete defects. In addition, the computational advantage compared to the Perona and Malik model, C-T model 1, C-T model 2, and histogram statistics model are about 4.48, 2.26, 19.53, and 26.63 times, respectively. It can be concluded that the proposed algorithm not only provides reliable inspection results but also improves the inspection efficiency over 2 times.

This paper analyses the optimal licensing strategy of a licensor firm that competes with potential licensee firms in an industry with endogenous entry. The optimal licensing strategy of the licensor firm is to have zero royalty and positive fixed fees, which is a result that sharply contrasts with the existing literature whereby licensor firms tend to charge positive royalties to their rival licensees. Under the optimal licensing strategy, the licensor firm and the licensee firms are active in the market, but not the non-licensed firms. This equilibrium market structure is socially desirable if the fixed production cost is not too small.

In this paper, a set of novel fuzzy adaptive control strategy is proposed to control two totally different nonlinear systems with complicated structure and different numbers of nonlinear terms. This novel adaptive control strategy is composed of three main points—(1) novel fuzzy model, proposed via Li and Ge (IEEE Trans Syst Man Cybern Part B Cybern 41(4):1015–1026, 2011), provides a set of simple and effective modeling strategy to reduce the total numbers of fuzzy rules through modeling process, and only two linear subsystems are needed; (2) novel control Lyapunov function is set as an exponential form of error states and tries to speed up the variance of states in this article; and (3) pragmatical asymptotically stability theorem: this theorem can be applied to proof that the error of parameters can achieve the original point strictly. Mathieu–Van der Pol system and quantum cellular neural networks nanosystem are used for illustrations in numerical simulation results to show the effectiveness and feasibility of the new fuzzy adaptive approach. Traditional fuzzy modeling and adaptive control method are given for further comparison.

This paper examines the welfare effects of spatial price discrimination. In the model a monopolist sells its product to a continuum of consumers distributed uniformly along a line market in which the market boundary is endogenously determined. We find that the monopolist always serves more consumers and sells more outputs under discriminatory pricing than under uniform pricing. Nevertheless, the welfare ranking between the two pricing policies is ambiguous. Results show that uniform pricing is more socially desirable than discriminatory pricing as long as the production cost function is sufficiently convex. This result is in sharp contrast to the finding in the literature that spatial price discrimination is more socially desirable than uniform pricing.

Mesh membranes are widely used in nebulizers for inhalation therapy in the medical industry and in piezoelectric actuators for humidifiers, so the most important dimension of a mesh membrane is the diameter of the circular holes. Traditionally, a number of holes in a mesh membrane and non-coplanar mesh membrane array are manually inspected, which is expensive and time consuming. To address this problem, this study develops a novel auto-focus measurement system, which includes the hardware and software systems. The hardware system is composed of the modules for the motion stage and the auto-focus optical mechanism. The software system consists of two phases: (1) training the general regression neural network (GRNN) for auto-focus technology, in the offline phase, and (2) automatically capturing sharp mesh images using a GRNN and reliably measuring holes using the three measurement algorithms, in the online phase. The results of the experiments confirm that the proposed auto-focus technology, which uses a GRNN, obtains the correct focus position. The accuracy of the measurement of the diameter of a hole can reach 0.89 μm, the successful measure rate is almost 98 % and the average measurement time is 4.8 s per mesh. These results show that the proposed system is not only robust for auto-focus technology, but also efficient and effective for the measurement of mesh membrane arrays.

This paper examines the welfare effect of third-degree price discrimination in a vertically related market with one upstream monopolist that sells its input to a continuum of downstream markets. Assume that the market boundary of the monopolist is endogenously determined. It is found that social welfare is necessarily lower under discriminatory than uniform pricing, even if the market area of the former is greater than that of the latter. This finding is contrary to that in the extant literature on price discrimination in final goods markets.

The requirements for high-speed and high-precision defect inspection in semiconductor chip are growing rapidly because of the complicated surface in semiconductor chip. Due to manufacturing tolerance of IC tray, the misalignment from the chip positioning shift and rotation are always presented for the application of in-tray inspection. In the beginning, this paper focuses on compensating the positioning shift and rotation of in-tray chip by using the proposed image alignment algorithm before the defect detection. After applying the process of image alignment, a hybrid approach of defect detection is applied to detect the defects of in-tray chip. Furthermore, this hybrid approach simultaneously detects the defects based on its surface by the following two categories: (1) the complicated surface in the circuit and (2) the primitive surface on the bump. As mentioned above, the image alignment strategy and the adaptive image difference method are applied in the detection of complicated surface, and the design-rule strategy is adapted to detect the defects on bumps. Finally, the experimental results show that the proposed image alignment strategy and hybrid approach can accurately and rapidly inspect the defects of in-tray chip. This approach is superior to the traditional template matching in defect detection. In addition, the computational complexity can be efficiently reduced by the proposed hybrid strategy.

Rapid prototyping technology makes the manufacturing of functionally graded material (FGM) objects possible. The FGM production process requires concurrent applications of digital design and manufacturing methods. For this reason, it is imperative to construct and capture information and other critical data regarding the geometry and materials about FGM objects for use in the manufacturing process. This paper proposes a simplex-clear data format for modeling FGM objects. This proposed data format captures both the geometry and material information of an FGM object. It also presents a finite element-based slicing algorithm which slices the FGM object into layers and captures each layer’s information for rapid prototyping manufacturing of the object. An example is given at the end of the paper to validate the data format and demonstrate the adaptive slicing algorithm.

The literature on vertical integration has constantly assumed a linear demand for the final good market. In this paper, we instead assume the demand to be a general one and use it to derive the welfare effect of vertical integration toward an export-oriented industry. It is shown that the effect of vertical integration on the intermediate good price depends on the curvature of the derived demand curve. Moreover, vertical integration is welfare-improving only if it increases the price of the intermediate good.