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The control of vibration in helicopters which consists of reducing vibration levels below the acceptable limit is one of the key problems. Active control of helicopter vibrations, with actuators in the air frame structure, is appealing in terms of simplicity, airworthiness, and effectiveness. In the field of active control of structural response (ACSR), actuator locations have an important influence...
The attitude control is the key of the automatic flight for a quad-rotor aircraft. In order to guarantee the robustness of the quad-rotor aircraft for various uncertainties, a new design method of the robust optimal control that integrates the sliding mode control theory with state-dependent Riccati equation (SDRE) is proposed in this paper. First, the whole attitude kinematical model is obtained...
The main purpose of this work is to design and implement a PLC-based control system framework for the beer fermentation process. Firstly, the technological process of beer brewing production is analyzed briefly. Furthermore, the details of the control demand for beer fermentation process are introduced as well. On the basis of actual beer production projects in breweries, this paper investigate automation...
For the problem of attitude control during UAV envelope flight, the parameter uncertainty in full envelope flight was treated as a model uncertainty robustness problem. This paper select the UAV pitch angle as the control object. In order to guarantee the robust performance of the control system, height from 500m to 1000m and speed from 80m/s to 220m/s, we chose 18 trim points, so we have 18 transfer...
Automated carrier landing of an Unmanned Air Vehicle is a complex process. To successfully complete the task of landing on carrier, firstly the guidance system should give UAV flight control system a proper landing trajectory, then the flight control system according to the instructions given by the guidance system of UAV make the UAV fly on the right track, finally realizing automatic landing on...
Quantitative feedback theory (QFT) is a robust control design method. QFT quantitatively mirror the system uncertainty and design performance target to the Nichols chart, so the designed control system could ensure the performance. Due to the parameter uncertainty in tiltrotor conversion process, using QFT method design the flight control system for tiltrotor conversion. Simulation shows that the...
The purpose of this paper is to confirm a scientific and reasonable core enterprise of tourism supply chain in China. First, with historical evolutionism and taxology methods we divided the development of Chinese tourism supply and demand system into two phases, one is a singleness frame phase with travel agency as the core, and the other is a doubleness frame phase with travel agency and tourist...
The purpose of this paper is to advance general theory of screen tourism marketing, and correct unreasonable behaviors of some tourist attractions on it. Based on comparison marketing and product lifecycle theories, we analyzed how Zhangjiajie and Huangshan spots do screen tourism marketing unscientifically with “Avatar”, and found the reason that screen marketing enhancing spots attraction is spots'...
The purpose of this paper is to establish a tourism environmental protection pattern including actively protection, developing protection and rebuilding protection, considered the fragile environment regions' characteristic. We employed inference and contrast analysis methods, exposed the disadvantage of traditional tourism environmental protection that environmental protection is disjoined with tourism...
There are three parts of this study. Firstly, we comprehensively surveyed the existing scientific and educational tourism resources, and analyzed its characteristics and comparative advantages. Secondly, we explored high-quality development model of the scientific and educational tourism resources in Wuhan from resources, products, and market. Finally, we designed three themes and six kinds of scientific...
The purpose of this paper is to propose a way for scientifically solving culture problems of tourism souvenir development based on cultural sociology. We employed deduction and induction methods to analyze from cultural mode, cultural conflict, cultural spread, and cultural flux, and found: tourism souvenir development should not only display cultural mode of tourist destination, but also consider...
The study on the coupling relationship between the variation of soil erosion and geomorphological factors in watershed scale will contribute to the effectiveness of soil and water conservation. Based on soil erosion database, the topographic variations of soil erosion in watershed and the relationship between it with different geomorphologic factors were analyzed in the paper, with a case study of...
The complexity of technology and structure of equipments increasing significantly raise challenges in equipment diagnosis. Extensive researches make us recognize that Design for Testability (DFT) must be carried out concurrently with functional design of equipments in order to fundamentally solve these problems. Diagnostic strategy design, as an important aspect during DFT, is crucial for reducing...
The purpose of this paper is to solve a controversial issue in Chinese tourism academia that which is optimum to be core node of tourism supply chain between tourist attraction and travel agency. Based on supply chain management theory and complied with the research paradigm "self-analysis-competition negation-practice test", the study analyzed the optimum qualification and advantages of...
This paper aims to improve efficiency in permanent magnet synchronous (PM) motor drives. The authors of this paper present a new algorithm of minimum input power search for vector-controlled interior permanent-magnet synchronous motor drives, through analysis and simulation show that the algorithm has faster convergence rate than existing methods.
Survivability of information system is different with various techniques in dynamic work conditions, and which can be classified into multiple grades according to corresponding capability. In an information system, customer needs to pay different service fee at different survivability grade and provider must invest considerable money so as to keep a particular survivability grade. A game-theory based...
A novel circularly polarized microstrip antenna which is designed based on the single complementary split ring resonator (SCSRR) is proposed. The analysis of current distribution on the patch using the complementary split ring resonator (CSRR) has enlightened on the design. The rules about parameters adjustment is studied through parametric analysis. One group of optimized parameters can be determined...
In this paper, a nonlinear PI controller is developed to control speed of PMSM, it can adjustment of controller parameters automatically in order to achieve the best control effect in control process. Simulation results show that it was faster than the traditional controller response and have a smaller overshoot.
A mechanism of survivability recovery, whereby component is the basic unit of being fixed, is presented for information system in this paper in order to overcome the deficiencies existed in approach on survivability recovery. Services provided in information system are classified into complete service, acceptable service and interrupted service by the degree of dependence on disable failed critical...
The purpose of this paper is systematically studying the problems of pro-poor tourism (PPT) in China based on supply chain management theory. By constructing the PPT supply chain, theoretically prescribed the general development direction and special role of PPT object in the chain, and advanced two strategies, adding assistant nodes and establishing e-business flat of PPT supply chain to improve...
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