Nonlinear Stochastic Drill-String Vibrations

2002 ◽  
Vol 124 (4) ◽  
pp. 512-518 ◽  
Author(s):  
P. D. Spanos ◽  
A. M. Chevallier ◽  
N. P. Politis
Keyword(s):  
System Analysis ◽  
Stochastic Dynamics ◽  
Moving Average ◽  
Equations Of Motion ◽  
Nonlinear Dynamic System ◽  
Drill String ◽  
Statistical Linearization ◽  
Oil Well ◽  
Analysis And Design ◽  
Measurement While Drilling

Lateral vibrations of drill-strings used in oil well operations are considered. A finite elements based discretization procedure leads to a nonlinear dynamic system which is used to represent the drill-string inertia and stiffness characteristics, as well as the elasticity of the wall of the well. Due to the erratic pattern and the uncertainty of the forces at the drill-bit, a stochastic dynamics approach is adopted in investigating the problem. The method of statistical linearization is used, and expressions for determining an equivalent linear system to model the drill-string dynamics are derived. Further, a Monte Carlo simulation of the system dynamics is conducted by means of an Auto Regressive Moving Average (ARMA) digital filter, and by integrating the equations of motion using the Newmark scheme. Numerical results pertaining to data obtained by measurement while drilling (MWD) tools are presented. It is hoped that this study will enhance the interest in using stochastic dynamics techniques in drilling system analysis and design, as they can capture quite appropriately the inherent uncertainty of the bit forces and, potentially, of other sources.

scholarly journals Versatility of constrained CRB for system analysis and design

2014 ◽  
Vol 50 (3) ◽  
pp. 1841-1863 ◽  
Author(s):  
Tarek Menni ◽  
Jerome Galy ◽  
Eric Chaumette ◽  
Pascal Larzabal
Keyword(s):  
System Analysis ◽  
System Analysis And Design ◽  
Analysis And Design

scholarly journals An automated system analysis and design tool for spacecrafts ceas space journal

2021 ◽  
Author(s):  
Manfred Ehresmann ◽  
Georg Herdrich ◽  
Stefanos Fasoulas
Keyword(s):  
Evolutionary Algorithms ◽  
Evolutionary Algorithm ◽  
Degrees Of Freedom ◽  
System Analysis ◽  
Propulsion System ◽  
Optimal System ◽  
Automated System ◽  
Processing Unit ◽  
Data Set ◽  
Analysis And Design

AbstractIn this paper, a generic full-system estimation software tool is introduced and applied to a data set of actual flight missions to derive a heuristic for system composition for mass and power ratios of considered sub-systems. The capability of evolutionary algorithms to analyse and effectively design spacecraft (sub-)systems is shown. After deriving top-level estimates for each spacecraft sub-system based on heuristic heritage data, a detailed component-based system analysis follows. Various degrees of freedom exist for a hardware-based sub-system design; these are to be resolved via an evolutionary algorithm to determine an optimal system configuration. A propulsion system implementation for a small satellite test case will serve as a reference example of the implemented algorithm application. The propulsion system includes thruster, power processing unit, tank, propellant and general power supply system masses and power consumptions. Relevant performance parameters such as desired thrust, effective exhaust velocity, utilised propellant, and the propulsion type are considered as degrees of freedom. An evolutionary algorithm is applied to the propulsion system scaling model to demonstrate that such evolutionary algorithms are capable of bypassing complex multidimensional design optimisation problems. An evolutionary algorithm is an algorithm that uses a heuristic to change input parameters and a defined selection criterion (e.g., mass fraction of the system) on an optimisation function to refine solutions successively. With sufficient generations and, thereby, iterations of design points, local optima are determined. Using mitigation methods and a sufficient number of seed points, a global optimal system configurations can be found.

Manufacturing Plant Management Information System Analysis and Design Based on UML

2010 ◽  
Vol 455 ◽  
pp. 237-241
Author(s):  
X.Y. Yang ◽  
H.B. Zheng ◽  
Z.W. Zhang
Keyword(s):  
Asset Management ◽  
System Analysis ◽  
Structural Model ◽  
System Development ◽  
Unified Modeling Language ◽  
Object Oriented ◽  
Plant Management ◽  
Management Information ◽  
Static Structure ◽  
Analysis And Design

With the development of manufacturing automation and intelligent increasing speed, the construction in plant management information has been important tasks to promote business innovation ability, improve competitiveness and manufacturing execution. In this paper, UML (Unified Modeling Language) and object-oriented modeling technology were applied to model the static structure and dynamic behavior of the plant management information from requirement analysis to system implementation, including functional requirement model, static structural model, asset management time sequence chart, system physical model and so on. The visualized system analysis method and technology better planned the system design and improved the efficiency of the system development. It will play a guiding role in the object-oriented software development.

OTEC Power System Modeling, Analysis and Design via Geometric Programming

1980 ◽  
Vol 102 (3) ◽  
pp. 154-159 ◽  
Author(s):  
A. Lavi
Keyword(s):  
Nonlinear Programming ◽  
Power System ◽  
Geometric Programming ◽  
Power Plants ◽  
System Analysis ◽  
System Modeling ◽  
Analytical Treatment ◽  
Transfer Energy ◽  
Analysis And Design ◽  
Operating Variables

A complex power system may be modeled by a system of inequalities representing the constraints imposed by the physical laws: heat transfer, energy balance, cycle efficiency and so forth. The nature of the resulting mathematical model is such that the terms contain complex expressions involving the design and operating variables of the process. With the addition of an objective function involving the cost of major system components, a multivariable nonlinear programming problem can be formulated. Seldom does the model lend itself to analytical treatment. This paper is concerned with a specific formulation and solution of nonlinear programming problems which arise in the design of ocean thermal energy conversion (OTEC) power plants. The technique used is geometric programming, GP. It is shown that GP serves as an excellent tool for system analysis because it provides sensitivity information essential to the designer.

SISTEM INFORMASI INVENTORY BARANG (SI RIANG) PADA PT SANGHIANG PERKASA

2021 ◽  
Vol 15 (4) ◽  
pp. 10-23
Author(s):  
Eka Chandra Ramdhani ◽  
Juniarti Eka Safitri ◽  
Selamat Abdurrahman Fahmi ◽  
Asep Asep
Keyword(s):  
System Analysis ◽  
System Development ◽  
Inventory System ◽  
Inventory Systems ◽  
Coding System ◽  
Process Data ◽  
Analysis And Design ◽  
Analysis System ◽  
Software Requirements Analysis

The inventory system is a system that has a very important role in a company. Inventory systems have been widely used or developed in a place with various technologies and systems. Problems at PT. Sanghiang Perkasa is due to the fact that the data has not been stored in a good file and the management and processing of inventory data is still processed in a conventional way, which has a very significant effect on the quality of the data and information produced. The main objective of this research is to produce an inventory system that is powerful and in accordance with the needs of the users associated with the inventory system. The system development method in this inventory system uses the waterfall method which consists of six stages. The stages are System Analysis and Design, software requirements analysis, system design, coding, system testing and maintenance. This system was built using the PHP programming language, DataBase MySQL. It is hoped that with the implementation of this inventory system at PT. Sanghiang Perkasa can make it easier to store and process data and information such as stock-taking data, information on incoming and outgoing goods transactions, purchase and sales return data, managing customer and supplier data to making product stock reports and assembly reports. Keywords: Information System; Inventory, Web

A Lumped Parameter Electromechanical Model for Describing the Nonlinear Behavior of Piezoelectric Actuators

1997 ◽  
Vol 119 (3) ◽  
pp. 478-485 ◽  
Author(s):  
M. Goldfarb ◽  
N. Celanovic
Keyword(s):  
System Analysis ◽  
Nonlinear Behavior ◽  
Piezoelectric Actuators ◽  
Bond Graph ◽  
Lumped Parameter Model ◽  
Input Output ◽  
Mechanical Stiffness ◽  
Analysis And Design ◽  
Lumped Parameter ◽  
Proposed Model

A lumped-parameter model of a piezoelectric stack actuator has been developed to describe actuator behavior for purposes of control system analysis and design, and in particular for control applications requiring accurate position tracking performance. In addition to describing the input-output dynamic behavior, the proposed model explains aspects of nonintuitive behavioral phenomena evinced by piezoelectric actuators, such as the input-output rate-independent hysteresis and the change in mechanical stiffness that results from altering electrical load. Bond graph terminology is incorporated to facilitate the energy-based formulation of the actuator model. The authors propose a new bond graph element, the generalized Maxwell resistive capacitor, as a lumped-parameter causal representation of rate-independent hysteresis. Model formulation is validated by comparing results of numerical simulations to experimental data.

scholarly journals Object Oriented VS Structured Analysis and Design in System Development Courses

2019 ◽  
Vol 8 (6S3) ◽  
pp. 82-88
Keyword(s):  
System Analysis ◽  
Survey Methodology ◽  
System Development ◽  
Object Oriented ◽  
Analysis And Design ◽  
Institutions Of Higher Learning ◽  
Structured Analysis ◽  
The One ◽  
Structured Analysis And Design

Objectives: The main aim of this study was to investigate the factors that influence students’, academicians’, clients’, as well as developer’s preferences in choosing their preferred approach in system development, namely structured analysis design (SAD) or object-oriented analysis and design (OOAD). Methods: The research design was based on a survey methodology and a case study. For the survey, questionnaires were administered to 30 students and 38 academicians, who were randomly selected from several Malaysian universities. For the case study, the requirements of the information system were modeled and presented to several clients to elicit their feedback. The survey data were analyzed using SPSS Findings: The result shows that students preferred the use of OOAD approach, which clearly outnumbered those who preferred the SAD approach, which stood at 33%. Interestingly, the majority (53%) of academicians preferred the use of a mixture of both approaches. Likewise, the clients shared a similar view with the academicians, whereas the developer preferred the OOAD approach. Application/Improvements: Clearly, the findings suggest that both approaches are essential, but the one that is widely used by developers and preferred by students is OOAD, and thus should be given priority when it comes to structured analysis and design. As such, curriculum designers and institutions of higher learning, particularly those offering system analysis and design and related courses, should make the necessary changes to the existing curriculum such that the academic programs offered will be able to produce highly competent and skilled analysts and designers as required by the industry.

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