Stability Analysis Research Papers - Academia.edu (original) (raw)

In this work an automatic impedance matching for wireless communication systems is proposed. A Takagi-Sugeno (T-S) fuzzy logic controller is used to change adaptively the value of one capacitor in the π matching network. Asymptotic... more

In this work an automatic impedance matching for wireless communication systems is proposed. A Takagi-Sugeno (T-S) fuzzy logic controller is used to change adaptively the value of one capacitor in the π matching network. Asymptotic stability is established via a common Lyapunov function for all the subsystems of the T-S fuzzy system. Results obtained using Verilog-A and a Least Mean Square (LMS) impedance matching approach are presented.

Abstract:- This paper details an original method for the stability analysis of mechatronic systems driven by asynchronous machines. The mathematical basis of the method and a few characteristics obtained with an adequate Matlab program... more

Abstract:- This paper details an original method for the stability analysis of mechatronic systems driven by asynchronous machines. The mathematical basis of the method and a few characteristics obtained with an adequate Matlab program are presented. The windows of the program for monitoring of the experimental tests are also depicted. Finally a series of experimental tests and the conclusions confirming the validity of the proposed method are presented. Key-Words:- stability, mechatronic system, asynchronous machine, variable frequency, parameters, software. 1

This article describes the use of GPR in urban slopes stability analysis. The studied slopes, located at Belo Horizonte County, Brazil, were named Planetóides and Rio Acima and, respectively, are composed by talus over phyllites and talus... more

This article describes the use of GPR in urban slopes stability analysis. The studied slopes, located at Belo Horizonte County, Brazil, were named Planetóides and Rio Acima and, respectively, are composed by talus over phyllites and talus over schist. Successive landslides have been occurred in these sites during rainy season. At Planetóides slope was possible to observe the talus depth and the presence of more than two circular landslide surface scars. At Rio Acima slope the geophysics profile made possible to observe the depth, orientation and intensity of the schistosity and fractures. These discontinuities are responsible for planar failures of the rock mass. The results of the GPR analysis together with other geotechnical studies made possible the detection of the main parameters used during stability analysis and helped in establishment of the failure mechanisms that had occurred in these slopes.

Robotic operations carried out via the Internet face several challenges and difficulties. These range from human-computer interfacing and human-robot interaction to overcoming random time delay and task synchronization. These limitations... more

Robotic operations carried out via the Internet face several challenges and difficulties. These range from human-computer interfacing and human-robot interaction to overcoming random time delay and task synchronization. These limitations are intensified when multi-operators at multisites are collaboratively teleoperating multirobots to achieve a certain task. In this paper, a new modeling and control method for Internet-based cooperative teleoperation is developed. Combining Petri net model and event-based ...

This paper investigates the system stability of a sampled-data fuzzy-model-based control system, formed by a nonlinear plant and a sampled-data fuzzy controller connected in a closed loop. The sampled-data fuzzy controller has an... more

This paper investigates the system stability of a sampled-data fuzzy-model-based control system, formed by a nonlinear plant and a sampled-data fuzzy controller connected in a closed loop. The sampled-data fuzzy controller has an advantage that it can be implemented using a microcontroller or a digital computer to lower the implementation cost and time. However, discontinuity introduced by the sampling activity complicates the system dynamics and makes the stability analysis difficult compared with the pure continuous-time fuzzy control systems. Moreover, the favourable property of the continuous-time fuzzy control systems which is able to relax the stability analysis result vanishes in the sampled-data fuzzy control systems. A Lyapunov-based approach is employed to derive the LMI-based stability conditions to guarantee the system stability. To facilitate the stability analysis, a switching fuzzy model consisting of some local fuzzy models is employed to represent the nonlinear plant to be controlled. The comparatively less strong nonlinearity of each local fuzzy model eases the satisfaction of the stability conditions. Furthermore, membership functions of both fuzzy model and sampled-data fuzzy controller are considered to alleviate the conservativeness of the stability analysis result. A simulation example is given to illustrate the merits of the proposed approach.

Measurements of converter input and output impedances are conducted to verify that the power system has been correctly modeled and designed. Many impedance measurement setups presented in the past are useful for tutorial purposes, but in... more

Measurements of converter input and output impedances are conducted to verify that the power system has been correctly modeled and designed. Many impedance measurement setups presented in the past are useful for tutorial purposes, but in practice their application is limited to low-power supplies. This paper presents practical impedance measurement circuits, which provide reliable measurements for a wide class of power supplies. The measured impedance data was applied to stability analysis of the computer distributed power system

Normalized Difference Vegetation Index (NDVI) is a crucial land surface characteristic derived from satellite data. NDVI derived from AVHRR/NOAA is now the most widely used in medium to large scale studies to determine vegetation-climate... more

Normalized Difference Vegetation Index (NDVI) is a crucial land surface characteristic derived from satellite data. NDVI derived from AVHRR/NOAA is now the most widely used in medium to large scale studies to determine vegetation-climate interactions. Experiments with MSG (METEOSAT 8/9) SEVIRI data have demonstrated a good potential for new generation imaging instruments onboard geostationary satellites to provide routine monitoring of the vegetation state through NDVI. In this study, we present pre-operational daily and weekly NDVI products derived from MSG SEVIRI data. Full disc MSG coverage red and near infrared bands are processed and the products are masked using the derived Cloud Mask products. Validation is performed against Land SAF fractional vegetation cover (FVC) products. Additionally, MSG NDVI products are compared with METOP AVHRR based NDVI products. Temporal stability analysis (diurnal change) is also performed.

In fixture design, a workpiece is required to remain stable throughout the fixturing and machining processes in order to achieve safety and machining accuracy. This requirement is verified by a function of the computer-aided fixture... more

In fixture design, a workpiece is required to remain stable throughout the fixturing and machining processes in order to achieve safety and machining accuracy. This requirement is verified by a function of the computer-aided fixture design verification (CAFDV) system. This paper presents the methodologies of fixturing stability analysis in CAFDV. A kinetic fixture model is created to formulate the stability problem, and a fixture stiffness matrix (FSM) is derived to solve the problem. This approach not only verifies fixturing stability, but also finds the minimum clamping forces, fixture deformation, and fixture reaction forces. The clamping sequence can also be verified with this approach.