609 research outputs found
A new methodology for designing PID controllers
It is known that it is impossible to select fixed gains for a PD controller that will critically damp the response to disturbances for all configurations of a given robot system. Because of this the potential for overshoot is always present and cannot be avoided unless the system is severely overdamped. This is not necessarily a practical solution and can be an economically unacceptable approach. On the other hand, however, if overshoot is permissible to some degree for some systems in the case of conventional Serial robots it is still prohibited in the case of Parallel robots as it may easily bring the robot to one of its possible singular configurations, causing damage to the system. This paper introduces a new algorithm for the design of PD controllers that ensures uniform and fast dynamic responses, which are free from overshoots for all robot configurations. The technique also satisfies general stability requirements for the system
Typology and microprobe analysis of zircons as an indicator to evolution and genesis of Abu El-Hasan granitoids, Northern-Eastern Desert, Egypt
Geochemistry, Tectonic setting and classification of some granitoids, Gebel Abu El-Hasan, North Eastern Desert, Egypt
Zeros of polynomials orthogonal with respect to a signed weight
AbstractIn this paper we consider the monic polynomial sequence (Pnα,q(x)) that is orthogonal on [â1,1] with respect to the weight function x2q+1(1âx2)α(1âx),α>â1,qâN; we obtain the coefficients of the tree-term recurrence relation(TTRR) by using a different method from the one derived in Atia et al. (2002) [2]; we prove that the interlacing property does not hold properly for (Pnα,q(x)); and we also prove that, if xn,nα+i,q+j is the largest zero of Pnα+i,q+j(x), x2nâ2j,2nâ2jα+j,q+j<x2nâ2i,2nâ2iα+i,q+i,0â€i<jâ€nâ1
VHDL Based Maximum Power Point Tracking of Photovoltaic Using Fuzzy Logic Control
It is important to have an efficient maximum power point tracking (MPPT) technique to increase the photovoltaic (PV) generation system output efficiency. This paper presents a design of MPPT techniques for PV module to increase its efficiency. Perturb and Observe method (P&O), incremental conductance method (IC), and Fuzzy logic controller (FLC) techniques are designed to be used for MPPT. Also FLC is built using MATLAB/ SIMULINK and compared with the FLC toolbox existed in the MATLAB library. FLC does not need knowledge of the exact model of the system so it is easy to implement. A comparison between different techniques shows the effectiveness of the fuzzy logic controller techniques. Finally, the proposed FLC is built in very high speed integrated circuit description language (VHDL). The simulation results obtained with ISE Design Suite 14.6 software show a satisfactory performance with a good agreement compared to obtained values from MATLAB/SIMULINK. The good tracking efficiency and rapid response to environmental parameters changes are adopted by the simulation results
Recommended from our members
Dynamic web forms development using RuleML. Building a framework using metadata driven rules to control Web forms generation and appearance.
Web forms development for Web based applications is often expensive, laborious, error-prone, time consuming and requires a lot of effort. Web forms are used by many different people with different backgrounds and a lot of demands. There is a very high cost associated with the need to update the Web application systems to achieve these demands.
A wide range of techniques and ideas to automate the generation of Web forms exist. These techniques and ideas however, are not capable of generating the most dynamic behaviour of form elements, and make Insufficient use of database metadata to control Web formsÂż generation and appearance.
In this thesis different techniques are proposed that use RuleML and database metadata to build rulebases to improve the automatic and dynamic generation of Web forms.
First this thesis proposes the use of a RuleML format rulebase using Reaction RuleML that can be used to support the development of automated Web interfaces. Database metadata can be extracted from system catalogue tables in typical relational database systems, and used in conjunction with the rulebase to produce appropriate Web form elements. Results show that this mechanism successfully insulates application logic from code and suggests that
Abstract
iii
the method can be extended from generic metadata rules to more domain specific rules.
Second it proposes the use of common sense rules and domain specific rules rulebases using Reaction RuleML format in conjunction with database metadata rules to extend support for the development of automated Web forms.
Third it proposes the use of rules that involve code to implement more semantics for Web forms. Separation between content, logic and presentation of Web applications has become an important issue for faster development and easy maintenance. Just as CSS applied on the client side to control the overall presentation of Web applications, a set of rules can give a similar consistency to the appearance and operation of any set of forms that interact with the same database. We develop rules to order Web form elements and query forms using Reaction RuleML format in conjunction with database metadata rules. The results show the potential of RuleML formats for representing database structural and active semantics.
Fourth it proposes the use of a RuleML based approach to provide more support for greater semantics for example advanced domain support even when this is not a DBMS feature. The approach is to specify most of the semantics associated with data stored in RDBMS, to overcome some RDBMSs limitations. RuleML could be used to represent database metadata as an external format
Forecasting Remission Time of a Treatment Method for Leukemia as an Application to Statistical Inference Approach
In this paper, Weibull-Linear Exponential distribution (WLED) has been investigated whether being it is a well - fit distribution to a clinical real data. These data represent the duration of remission achieved by a certain drug used in the treatment of leukemia for a group of patients. The statistical inference approach is used to estimate the parameters of the WLED through the set of the fitted data. The estimated parameters are utilized to evaluate the survival and hazard functions and hence assessing the treatment method through forecasting the duration of remission times of patients. A two-sample prediction approach has been applied to obtain a predictive sample based on the Bayes estimates of the parameters. The statistical inference approach is applied to the case of censored data namely Type-II hybrid censoring scheme, which is common in clinical studies
Association between Low Adiponectin Level and Cardiovascular Complications in Diabetic and non Diabetic Patients with End Stage Renal Disease
Introduction: Adiponectin is a collagen-like protein synthesized by adipose tissue that has anti-inflammatory and anti-atherogenic properties. We aimed to evaluate adiponectin levels in end stage renal disease (ESRD) patients with and without diabetes mellitus and its relation to the presence of cardiovascular complications (CVC).
Methods: The study included 20 healthy subjects who served as controls (group I), 20 non-diabetic ESRD patients without CVC (group IIA), 20 non-diabetic ESRD patients with CVC (group IIB), 20 diabetic ESRD patients without CVC (group IIIA) and 20 diabetic ESRD patients with CVC (group IIIB). Evaluation included mean arterial blood pressure (MABP), body mass index (BMI), fasting plasma glucose, fasting plasma insulin, homeostasis model assessment for insulin resistance (HOMA-IR), lipid profile, and serum adiponectin levels.
Results: Adiponectin level in the control group was 6.4±1.2 mcg/ml, and was significantly lower than both group II and III (
Modeling and Control PV-Wind Hybrid System Based On Fuzzy Logic Control Technique
As energy demands around the world increase, the need for a renewable energy sources that will not harm the environment is increased. The overall objective of renewable energy systems is to obtain electricity with competitive cost and even benefit with respect to other energy sources. The optimal design of renewable energy system can significantly improve the economical and technical performance of power supply. This paper presents the power management control using fuzzy logic control technique. Also, a complete mathematical modeling and MATLAB/Simulink model for the proposed the electrical part of an aquaculture system is implemented to track the system performance. The simulation results show the feasibility of control technique
- âŠ