Semantic Product Requirement Network as Approaches for a Requirement Terminology and Tool for Linguistic Analysis of Requirements in Continuous Text

2008 ◽  
Author(s):  
Youssef Chahadi ◽  
Herbert Birkhofer
Keyword(s):  
Mathematical Model ◽  
Graph Theory ◽  
Sheet Metal ◽  
Collaborative Research ◽  
Linguistic Analysis ◽  
Customer Requirements ◽  
Identification Process ◽  
Metal Construction ◽  
Continuous Text ◽  
Branched Structures

The Collaborative Research Center 666 (CRC666) is concentrated on the research of methods and procedures for the optimized illustration of branched structures in integral sheet metal construction by regarding their functions and strains [1]. The virtual development of such branched structures emphasizes the found methods and procedures with regard to make them based on algorithms. This paper describes several approaches, which help to identify customer requirements based on algorithms. A standardized structure for the requirements is developed that builds the basis for a system of requirement terms. Product requirements can have relations among themselves. To make these relations directly and automatically available for the stakeholders during the identification process a semantic product requirement network was developed. This network helps the stakeholders to clearly identify and handle the requirements. This semantic product requirement network is based on the graph theory. A mathematical model for the access to the graph nodes (requirement) is introduced in the system for requirement terms that helps with the identification of requirements by using algorithms. Today requirements for a product are also collected in the form of a continuous text. For this case an approach is shows how requirements can be extracted from the continuous text by using linguistic procedures within the semantic product requirement network.

Study on the Generalized Holo-Factors Mathematical Model of Dimension-Error and Shape-Error for Sheet Metal in Stamping Based on the Back Propagation (BP) Neural Network

2016 ◽  
Vol 138 (6) ◽  
Author(s):  
Lizhi Gu ◽  
Tianqing Zheng
Keyword(s):  
Neural Network ◽  
Mathematical Model ◽  
Sheet Metal ◽  
Bp Neural Network ◽  
Back Propagation ◽  
Shape Error ◽  
Back Propagation Algorithm ◽  
Minor Strain ◽  
Major Strain ◽  
Forming Precision

Precision improvement in sheet metal stamping has been the concern that the stamping researchers have engaged in. In order to improve the forming precision of sheet metal in stamping, this paper devoted to establish the generalized holo-factors mathematical model of dimension-error and shape-error for sheet metal in stamping based on BP neural network. Factors influencing the forming precision of stamping sheet metal were divided, altogether ten factors, and the generalized holo-factors mathematical model of dimension-error and shape-error for sheet metal in stamping was established using the back-propagation algorithm of error based on BP neural network. The undetermined coefficients of the model previously established were soluble according to the simulation data of sheet punching combined with the specific shape based on the BP neural network. With this mathematical model, the forecast data compared with the validate data could be obtained, so as to verify the fine practicability that the previously established mathematical model had, and then, it was shown that the generalized holo-factors mathematical model of size error and shape-error had fine practicality and versatility. Based on the generalized holo-factors mathematical model of error exemplified by the cylindrical parts, a group of process parameters could be selected, in which forming thickness was between 0.713 mm and 1.335 mm, major strain was between 0.085 and 0.519, and minor strain was between −0.596 and 0.319 from the generalized holo-factors mathematical model prediction, at the same time, the forming thickness, the major strain, and the minor strain were in good condition.

The Automatic Generation of a Mathematical Model for Machinery Systems

1973 ◽  
Vol 95 (2) ◽  
pp. 629-635 ◽  
Author(s):  
D. A. Smith ◽  
M. A. Chace ◽  
A. C. Rubens
Keyword(s):  
Mathematical Model ◽  
Graph Theory ◽  
Computer Program ◽  
Mechanical System ◽  
Input Data ◽  
Automatic Generation ◽  
Electrical Networks ◽  
Lagrange’S Equation ◽  
Detailed Explanation ◽  
Independent Loops

This paper presents a detailed explanation of a technique for automatically generating a mathematical model for machinery systems. The process starts from a relatively small amount of input data and develops the information required to model a mechanical system with Lagrange’s equation. The technique uses elements of graph theory which were developed for electrical networks. The basic identifications required for mechanical systems are: paths from ground to mass centers, the independent loops of parts, if any, and paths associated with applied force effects. The techniques described in this paper have been used successfully in a generalized computer program, DAMN.

scholarly journals Cryptographic Recursive Control of Integrity of Metadata Electronic Documents. Part 1. Mathematical Model

2020 ◽  
pp. 2-18
Author(s):  
Dmitry Tali ◽  
◽  
Oleg Finko ◽  
◽  
Keyword(s):  
Mathematical Model ◽  
Graph Theory ◽  
Information Systems ◽  
Control Method ◽  
Research Result ◽  
Document Management ◽  
Technical Solution ◽  
Electronic Document ◽  
Electronic Documents ◽  
Electronic Document Management

The purpose of the research is to increase the level of security of electronic document metadata in the face of destructive influences from authorized users (insiders). Research methods: new scientific results allowed using a combination of data integrity control method based on the «write once» method and of authentication of HMAС messages (hash-based message authentication, as well as graph theory methods. Research result: a method of cryptographic recursive 2-D control of the integrity of electronic documents metadata is proposed. The analysis of the object of the study was carried out, based on the results of which it was concluded that it is necessary to effectively protect the metadata of electronic documents processed by automated information systems of electronic document management. Developed and described a mathematical model of the proposed method, based on graph theory. The developed technical solution makes it possible to implement the functions of cryptographic recursive twodimensional control of the integrity of the metadata of electronic documents, as well as to provide the possibility of localizing modified (with signs of violation of integrity) metadata records, in conditions of destructive influences of authorized users (insiders). This, in turn, reduces the likelihood of collusion between trusted parties by introducing mutual control over the results of their actions. The proposed solution makes it possible to ensure control of the integrity of data processed by departmental automated information systems of electronic document management, where, due to the peculiarities of their construction, it is impossible to effectively use the currently popular blockchain technology.

Research and Application of Adaptive Technology in Equipment Installation

2014 ◽  
Vol 596 ◽  
pp. 94-99
Author(s):  
Bin Luo ◽  
Li Ye
Keyword(s):  
Mathematical Model ◽  
Paper Analysis ◽  
Current Situation ◽  
Customer Requirements ◽  
Adaptive Technology ◽  
The Mathematical Model

Based on the current situation that the accuracy of stress , displacement and trip in the traditional equipment installation can’t satisfy customer requirements. First, this paper analysis the principle of adaptive technology . Then , by establishing the mathematical model of stress and displacement ,the equipment automatically select the appropriate pressure and displacement values to ensure parts assembly optimal.

scholarly journals Application of Linear and Nonlinear Graphs in Structural Synthesis of Kinematic Chains

1973 ◽  
Vol 95 (2) ◽  
pp. 525-532 ◽  
Author(s):  
M. Huang ◽  
A. H. Soni
Keyword(s):  
Mathematical Model ◽  
Graph Theory ◽  
Structural Analysis ◽  
Three Dimensional ◽  
Structural Synthesis ◽  
Kinematic Chains ◽  
Piston Cylinder ◽  
General Constraints ◽  
Analysis And Synthesis ◽  
Linear And Nonlinear

Using graph theory and Polya’s theory of counting, the present paper performs structural synthesis and analysis of planar and three-dimensional kinematic chains. The Section 2 of the paper develops a mathematical model that permits one to perform structural analysis and synthesis of planar kinematic chains with kinematic elements such as revolute pairs, cam pairs, springs, belt-pulley, piston-cylinder, and gears. The theory developed is applied to enumerate eight-link kinematic chains with these kinematic elements. The Section 3 of the paper develops a mathematical model that permits one to perform structural analysis and synthesis of multi-loop spatial kinematic chains with higher and lower kinematic pairs. The theory developed is applied to enumerate all possible two-loop kinematic chains with or without general constraints.

scholarly journals The improvement of bolted joints model via finite element model updating method

2021 ◽  
Vol 15 (4) ◽  
pp. 8635-8643
Author(s):  
M. A. Yunus ◽  
M.N. Abdul Rani ◽  
M.A.S. Aziz Shah ◽  
M.S.M. Sani ◽  
Z. Yahya
Keyword(s):  
Mathematical Model ◽  
Sheet Metal ◽  
Dynamic Behaviour ◽  
Model Updating ◽  
Thin Sheet ◽  
Local Deformation ◽  
Bolted Joints ◽  
Fe Model ◽  
Thin Sheet Metal ◽  
Fe Model Updating

Efficient schemes to represent mathematical model of thin-sheet metal structures jointed by bolted joints for accurately predict the structure dynamic behaviour has been a significant unresolved issue in structural dynamics community. The biggest challenge is to efficiently incorporate the joints local deformation effects on the developed mathematical model via finite element (FE) method. Generally, the joints local deformation typically exerts on the joints mating area. To solve this issue, this paper proposes efficient schemes to represent mathematical model of thin-sheet metal structures jointed by bolted joints with application to accurately calculate the structure dynamic behaviour using FE model updating method. The initial FE model of the assembled structure was developed by employed Fastener Connector (CFAST) in MSC NASTRAN software to represent the bolted joints while, the inclusion of the local deformation effects at the bolted joints mating area was represented by contact elements. Then, the responses obtained from the FE model was evaluated by weight up with experimental data. FE model updating (FEMU) method then was utilised for minimising prediction discrepancies originated from the initial FE model based on the experimental data. The proposed scheme shows the accuracy of the initial prediction was improved from 25.03 % to 14.65 %  while the accuracy of the predicted mode shapes via modal assurance criterion (MAC) analysis were above 0.8. Therefore, the findings offer useful schemes for improving the quality of predicted dynamic behaviour, particularly in the thin-sheet metal jointed structure and the developed model can be used with confident for any subsequence dynamic analyses.

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