An Intelligent Real Time Design Methodology for Component Selection: An Approach to Managing Uncertainty

1994 ◽  
Vol 116 (4) ◽  
pp. 980-988 ◽  
Author(s):  
S. R. Bradley ◽  
A. M. Agogino
Keyword(s):  
Real Time ◽  
Design Methodology ◽  
Limited Resources ◽  
Rolling Element Bearings ◽  
Component Selection ◽  
Rolling Element ◽  
Improved Design ◽  
The Cost ◽  
Component Database ◽  
Selection Of

An Intelligent Real Time Design (IRTD) methodology is presented for component selection applications under the reality of uncertain and incomplete information. A decision analytic approach is developed with the goal of assisting designers in making decisions that balance the cost of the limited resources consumed during the design process, such as the designer’s time, against the benefit to be derived from the utilization of those resources in terms of expectations of an improved design. This approach is shown to complement other formal methods for design based on interval arithmetic and qualitative optimization, and a general methodology is proposed for performing component selection utilizing a combination of these methods. An example application to the selection of rolling element bearings is presented to clarify the methodology and demonstrate its effectiveness in providing guidance to designers when selecting elements from a component database.

An Intelligent Real Time Design Methodology for Catalog Selection

1991 ◽  
Author(s):  
S. R. Bradley ◽  
Alice M. Agogino
Keyword(s):  
Real Time ◽  
Design Methodology ◽  
Analytic Approach ◽  
Limited Resources ◽  
Rolling Element Bearings ◽  
Time Problem ◽  
Rolling Element ◽  
Improved Design ◽  
The Cost ◽  
Selection Of

Abstract An Intelligent Real Time Problem Solving (IRTPS) methodology is presented for catalog selection applications. A decision analytic approach is developed with the goal of assisting designers in making decisions during catalog selection that balance the cost of the limited resources consumed during the design process, such as the designer’s time, against the benefit to be derived from the utilization of those resources in terms of expectations of an improved design. This decision analytic approach is shown to complement other formal methods for design based on interval arithmetic and qualitative optimization, and a general methodology is proposed for performing catalog selection utilizing a combination of these methods. An example application to the selection of rolling element bearings is presented to clarify the methodology.

A PEAK ENERGY CRITERION (P. E.) FOR THE SELECTION OF RESONANCE BANDS IN COMPLEX SHIFTED MORLET WAVELET (CSMW) BASED DEMODULATION OF DEFECTIVE ROLLING ELEMENT BEARINGS VIBRATION RESPONSE

2009 ◽  
Vol 07 (04) ◽  
pp. 387-410 ◽  
Author(s):  
KONSTANTINOS C. GRYLLIAS ◽  
IOANNIS ANTONIADIS
Keyword(s):  
Energy Criterion ◽  
Vibration Response ◽  
Frequency Resolution ◽  
Center Frequency ◽  
Index Number ◽  
Rolling Element Bearings ◽  
Time Frequency ◽  
Peak Energy ◽  
Rolling Element ◽  
Selection Of

Complex Shifted Morlet Wavelets (CSMW) present a number of advantages when used for the demodulation of the vibration response of defective rolling element bearings: (A) They present the optimally located window simultaneously in the time and in the frequency domains; (B) They allow for the maximal time-frequency resolution; (C) The magnitudes of the complex wavelet coefficients in the time domain lead directly to the required envelope; (D) They allow for the optimal selection of both the center frequency and the bandwidth of the requested filter. A Peak Energy criterion (P. E.) is proposed in this paper for the simultaneous automatic selection of both the center frequency and the bandwidth of the relevant wavelet window to be used. As shown in a number of application cases, this criterion presents a more effective behavior than other criteria used (Crest Factor, Kurtosis, Smoothness Index, Number of Peaks), since it combines the advantages of energy based criteria, with criteria characterizing the spikiness of the response.

Innovative sustainable methodology for managing in-house software development in SMEs

2018 ◽  
Vol 25 (3) ◽  
pp. 1085-1103 ◽  
Author(s):  
Abbas Tarhini ◽  
Manal Yunis ◽  
Abdul-Nasser El-Kassar
Keyword(s):  
Design Methodology ◽  
Development Process ◽  
System Development ◽  
Content Type ◽  
Agile Methodology ◽  
The Past ◽  
Database Technology ◽  
The Cost ◽  
Selection Of

Purpose The purpose of this paper is to present an innovative agile methodology that proposes fundamental changes in managing the development of in-house information systems in small- and medium-sized enterprises (SMEs) and benchmarks it with one of two database technologies enabling these systems to be both efficient and competitive. Design/methodology/approach The objectives are achieved by presenting an elaborated design of the agile methodology that manages the system development process by addressing three basic components: roles played by system players, process needed to fulfill the system development, and artifacts to document the project. A case study is conducted as a proof of the effectiveness of the proposed methodology and measures whether the selection of the database technology affects the effectiveness of the system development process. Findings Results show that, compared with traditional methodologies, the proposed methodology reduced the cost of system development and testing by 30 percent and enhanced the IT – business alliance. Further, this work found that the selection of a suitable database technology is strongly related to the complexity and interrelationships between the data used. Originality/value Such research did not receive the needed attention (Hunter, 2004) even in the past decade. Successful adoption of IT by companies could be in the form of customized IS which could be expensive for SMEs to adopt due to a lack in technical expertise and financial resources. The proposed methodology has the potential to promote sustainable development through helping SMEs in reducing the time and cost of IT project development.

Feasibility Analysis for the Rotordynamic Performance of API617

2005 ◽  
Vol 127 (2) ◽  
pp. 418-424 ◽  
Author(s):  
Hyeong-Joon Ahn ◽  
Eric H. Maslen ◽  
Tetsuya Iwasaki
Keyword(s):  
Transfer Functions ◽  
Control Design ◽  
Rolling Element Bearings ◽  
Worst Case ◽  
Direct Assessment ◽  
Rolling Element ◽  
Speed Range ◽  
Direct Guidance ◽  
Bearing Dynamics ◽  
Selection Of

The rotordynamic performance of API 617 standards provides two primary requirements. First, the standard stipulates system damping near the expected operating speed range. Second, the standard requires a specific bound of the worst case unbalance response. The problem this poses for machine designers is (1) feasibility: can bearings be designed for a given rotor to meet API 617 and (2) if so, how can these bearings be designed? Our primary effort in this research is to convert the API requirements to a control design objective for a bearing. This permits direct assessment of the feasible design problem as well as providing a means to synthesize optimal bearing dynamics. In addition to providing synthesis of magnetic bearings, the resulting bearing transfer functions give direct guidance to selection of more conventional fluid film or rolling element bearings.

Optimal Frequency Band Selection for the Square Envelope Spectrum in the Diagnostics of Rolling Element Bearings

2014 ◽  
Author(s):  
S. Chatterton ◽  
P. Borghesani ◽  
P. Pennacchi ◽  
A. Vania
Keyword(s):  
Frequency Band ◽  
Vibration Signal ◽  
Band Selection ◽  
Rolling Element Bearings ◽  
Optimal Frequency ◽  
Simple Method ◽  
Rolling Element ◽  
Envelope Spectrum ◽  
Bearing Damage ◽  
Selection Of

Diagnostics of rolling element bearings is usually performed by means of a second-order cyclostationary tool applied to the vibration signal, due to the stochastic nature of the contact between the defect and the bearing rolling elements. The most used and simple method is the Envelope Analysis that is based on the identification of bearing damage frequency components in the so-called Square Envelope Spectrum. The main critical point of this technique is the selection of a suitable frequency band for the demodulation of the vibration signal. The most used approach for the frequency band selection is based on the evaluation of the band-Kurtosis index by mean of diagrams as the frequently used Fast Kurtogram or the more recent Protrugram. Both of them may fail in the selection of the optimal frequency band when other vibration sources affect the Kurtosis index. Also critical is the constancy in the time of this optimal band. In the paper, an experimental case of a bearing damage is investigated and an alternative approach for the filter band selection, the so-called “PeaksMap”, will be proposed by the authors and compared with the ones available in the literature.

Diagnostics of Rolling Element Bearings by Means of the Higuchy Fractal Dimension

2015 ◽  
Author(s):  
Steven Chatterton ◽  
Paolo Pennacchi ◽  
Andrea Vania ◽  
Phuoc Vinh Dang ◽  
Filippo Cangioli
Keyword(s):  
Fractal Dimension ◽  
Critical Point ◽  
Rolling Element Bearing ◽  
Rolling Element Bearings ◽  
Damage Indicator ◽  
Rolling Element ◽  
Element Bearing ◽  
The Common ◽  
Higuchi Fractal Dimension ◽  
Selection Of

In the field of rolling element bearing, the degradation of bearing health could be detected by means of suitable damage indexes. Band-Kurtosis index, that is the kurtosis value of the band-filtered signal, is often assumed. The critical point of this approach is the selection of a suitable filter band. In the paper, the use of a chaos metrics, namely the Higuchi fractal dimension as damage indicator is described. The trend of this index is compared with the common approach of band-kurtosis indicator for an experimental case of a rolling element bearing in which the defect developed until a permanent failure.

Feasibility Analysis for the Rotordynamic Performance of API617

2003 ◽  
Author(s):  
Hyeong-Joon Ahn ◽  
Eric H. Maslen ◽  
Tetsuya Iwasaki
Keyword(s):  
Transfer Functions ◽  
Control Design ◽  
Rolling Element Bearings ◽  
Worst Case ◽  
Direct Assessment ◽  
Rolling Element ◽  
Speed Range ◽  
Direct Guidance ◽  
Bearing Dynamics ◽  
Selection Of

The rotordynamic performance of API 617 standards provides two primary requirements. First, the standard stipulates system damping near the expected operating speed range. Second, the standard requires a specific bound of the worst case unbalance response. The problem this poses for machine designers is 1) feasibility: can bearings be designed for a given rotor to meet API 617 and 2) if so, how can these bearings be designed? Our primary effort in this research is to convert the API requirements to a control design objective for a bearing. This permits direct assessment of the feasible design problem as well as providing a means to synthesize optimal bearing dynamics. In addition to providing synthesis of magnetic bearings, the resulting bearing transfer functions give direct guidance to selection of more conventional fluid film or rolling element bearings.

Is it worth doing fieldwork with this organisation? A method for considering context before conducting fieldwork research in Sport for development and peace.

2020 ◽  
Author(s):  
Tegwen Gadais ◽  
Laurie Décarpentrie ◽  
Andrew Webb ◽  
Marie Belle Ayoub ◽  
Mariann Bardocz-Bencsik ◽  
...  
Keyword(s):  
Sustainable Development ◽  
Research Method ◽  
Sustainable Development Goals ◽  
Field Work ◽  
Limited Resources ◽  
Limited Time ◽  
Sport For Development ◽  
Development Goals ◽  
The Cost ◽  
Existing Data

Much has been written about sport as a tool for development and peace. But more research on Sport for Development and Peace (SDP) organizations, is needed to better understand their actual contributions to the UNs sustainable development goals. Yet, the unstable, risky, and restricted contexts in which many NGOs and SDP agencies operate often leaves researchers struggling to find effective yet feasible methods through which to examine agencies in these fields. Indeed, conducting field work on and with SDP agency often implies allocating significant quantities of researcher’s limited time, funding, and other vital resources. And as limited resources need to be invested wisely, SDP researchers will clearly need to prepare their fieldwork. Nevertheless, there are but a handful of methodological papers that address the question of how to prepare for SDP field work. In other words, the question of how we know if it is worthwhile, and safe enough, to proceed with SDP field work remains. Building on previous research, the purpose of this study is to raise important ontological and epistemological questions about what can be known about a given context, before setting off on fieldwork. We further explore the use of the Actantial Model as a research method for analyzing existing data before deciding whether to conduct fieldwork in complex and frequently insecure situations. In other words, will the cost (material, temporal, financial, and physical) of conducting fieldwork be worth it? By applying the Actantial Model, with the specific aim of informing decisions regarding subsequent fieldwork, to one specific case, contributions regarding the pertinence of conducting fieldwork are provided.

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