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The charge collection probability is one of the most important parameters of a solar cell. We derived two kinds of special functions to fit the external quantum efficiency and use then to reconstruct the charge collection probability. The simulation results of gallium arsenide and silicon solar cells are put into comparison.
The advent of low-cost, functional robots has promoted swarm robotics research. However, an area of research that is yet untouched is how these types of robots could aid in teaching STEM subjects. In particular, there is little work concerning mathematics at the elementary level. The Kilobot robot's size, cost, and functionality offers a good test-bed to explore its use as a pedagogical tool. This...
In this paper, a flexible in-vessel inspection robot for inspecting the first wall inside the vacuum vessel of Experimental Advanced Superconducting Tokamak (EAST) is modeled using the absolute nodal coordinate formulation. The robot is a macro-micro robot including three curved telescopic booms. When the curved telescopic booms are extracted and retracted during the operation process, its overall...
Considering nonlinear and energy dissipation characteristics of STATCOM, realization of the generalized Hamiltonian system based on the model of system, and design nonlinear controller. This paper discussed the generalized Hamiltonian system and its realization, and established nonlinear dynamic model according to the work principle of STATCOM, completed realization of the generalized Hamiltonian...
This paper proposes two methods for solving the expert finding problem. In order to enhance the correctness, a C-value method is applied to these methods for query expansion. After query expansion, proposed system calculates correlation between all query terms and experts, and finally outputs a list of experts. The experiment results show that the proposed methods can provide higher precision than...
This paper presents a prognosis algorithm for the tension on ice-coated AC transmission lines. Firstly, the difference time sequences are built with the collected tension data on ice-coated AC transmission lines. Then the autoregressive model is applied on the obtained difference sequences and the model parameters are estimated through the Yule-Walk method. Finally, we can predict the tension on ice-coated...
Service providers of SNSs (Social networking services) offer new alternatives for users. The SNSs providers offer integrated service platforms supporting many devices and services. This study tries to discuss the driving forces of the value of SNSs. The issue of SNS has become more and more important and researchers began to put emphasis on the user behavior in SNSs platforms and how the SNSs change...
It has important theoretical and practical significance for urban agglomerationSs functional integration. Based on functional integration in the urban agglomeration and its effect with qualitative analysis¡Ataking Yunnan central urban agglomeration for example, this paper examins and measurements the development effects of functional integration, by building co-integration equation and spatial convergence...
By analyzing node equations in gas network, a mathematical model of steady-state calculation in urban pipeline with node method was established. Computer programs using MATLAB have been written. The algorithm can be used for hydraulic adjustment calculation in multi-circle city transmission and distribution pipeline networks, for optimization and for analysis of operating and accident conditions,...
This study aims to determine customers' needs, determine their desired music services, and propose suitable development strategies and operation models for digital music service providers. This study generated selected aspects/criteria for customers to evaluate their music platform preferences and their willingness to use digital music services. In this study, the Fuzzy cognitive map (FCM) was employed...
According to characteristics of mixed vehicle routing problem with backhauls, a mathematical model is constructed. An Adaptive Memory Programming Algorithm is proposed to solve this problem. Experiments are done and analyzed to prove the rationality of the model and effectiveness of the given algorithm.
This article contributes to solve time optimal path planning of robot applied remote real-time snooker match. According to characteristics of this problem, difficulties and key points, a new method is proposed in this paper for near minimum-time path planning of this problem which converts actual model 1 based on the problem into abstract model 2. And then Matlab program is written to calculate solution...
In this paper, the author make the grey forecast united with the fuzzy synthetic assessment to determine the regional classification problems for regulating and planning groundwater. In this case, the following models are adopted to forecast the water quality system: GM(1, 1) model groups, GM(1, 1) residual difference model, GM(1, N), GM(1, 1) Weighted model.
As an agricultural country, there are many nature disasters taken place in successive years, and they caused great loss to the peasant-household. But our compensation mechanism is distempered currently, so it is necessary to construct a compensation mechanism which is fit to the situation of China. The system entropy is about the complexity of the system, the relations of orderly structure and the...
The stick-slip oscillation in the drilling process can stall the drill bit and cause the equipment failure. In order to eliminate the stick-slip oscillation of the bit, the paper presents the adaptive PID control strategy of the drilling rotary system. The identification of adaptive control can ensure the drilling rotary system's output tracking and maintain the optimal work condition during the wide...
In the paper, the principle of speed governor of synchronous machine is discussed firstly. Based on this, mathematical models of the speed governors of BPA and PSS/E are compared to find the corresponding relationship of the speed governor models between BPA and PSS/E. The corresponding models have been validated by simulation of a single machine infinite bus system and the quantitative analysis of...
Due to the enhancement of web service and people's love needs, social networking service is emerging and getting more and more popular in recent years. Recently, social games have been drawing much attention. Social games contributed more people to play online games, and to extend their social networks. The popularity of social games also changed the operation model of online games. High production...
It is the more difficult to control when system is at low speed, the delay in speed measurement is a potential risk to controller stability, and friction as well. When controlling a super-low speed device, the stick-slip phenomenon appears. The precision and stability of speed are the key indexes. The mathematical model of PMSM and the system step response are analyzed, the Stribeck nonlinear friction...
With rapid development of wind power generation, the large capacity wind farms are built up and integrated into transmission network. The effect of wind farms on the grid becomes more serious and more extensive. In order to investigate the dynamic performances of the grid-connected wind farm and the interaction of the wind farms, it is necessary to present the appropriate models of wind farms, which...
Precision linearization control of IPMSM system is realized with nonlinear state feedback and coordinates transformation. The IPMSM is decomposed into two linear subsystems, d-axis flux subsystem and rotation speed subsystem. Simulation results show that IPMSM control system based on the design of input and output decoupling and linearization achieves high dynamic performance than the ordinary field...
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