METHODS: Simultaneous optimization of biomass and protease biosynthesis by a local isolatedPseudomonassp. — Selection of main medium components and operating conditions

2011 ◽  
Vol 7 (1) ◽  
pp. 53-62 ◽  
Author(s):  
María Victoria Agüero ◽  
Catalina Elena Kotlar ◽  
Sara Inés Roura
Keyword(s):  
Operating Conditions ◽  
Simultaneous Optimization ◽  
Medium Components ◽  
Main Medium ◽  
Selection Of

A Solution Framework for Response Surface-Based Multiple Quality Characteristics Optimization

2018 ◽  
Vol 25 (05) ◽  
pp. 1850025
Author(s):  
Sasadhar Bera ◽  
Indrajit Mukherjee
Keyword(s):  
Response Surface ◽  
Optimization Problems ◽  
Real Life ◽  
Quality Characteristics ◽  
Operating Conditions ◽  
Simultaneous Optimization ◽  
Trade Off ◽  
Multiple Quality Characteristics ◽  
Pin On Disc ◽  
Application Potential

A common problem generally encountered during manufacturing process improvement involves simultaneous optimization of multiple ‘quality characteristics’ or so-called ‘responses’ and determining the best process operating conditions. Such a problem is also referred to as ‘multiple response optimization (MRO) problem’. The presence of interaction between the responses calls for trade-off solution. The term ‘trade-off’ is an explicit compromised solution considering the bias and variability of the responses around the specified targets. The global exact solution in such types of nonlinear optimization problems is usually unknown, and various trade-off solution approaches (based on process response surface (RS) models or without using process RS models) had been proposed by researchers over the years. Considering the prevalent and preferred solution approaches, the scope of this paper is limited to RS-based solution approaches and similar closely related solution framework for MRO problems. This paper contributes by providing a detailed step-by-step RS-based MRO solution framework. The applicability and steps of the solution framework are also illustrated using a real life in-house pin-on-disc design of experiment study. A critical review on solution approaches with details on inherent characteristic features, assumptions, limitations, application potential in manufacturing and selection norms (indicative of the application potential) of suggested techniques/methods to be adopted for implementation of framework is also provided. To instigate research in this field, scopes for future work are also highlighted at the end.

Adaptation Application to Engine Modelling

2007 ◽  
Author(s):  
Jude Iyinbor
Keyword(s):  
Measurement Data ◽  
Engine Performance ◽  
Performance Model ◽  
Operating Conditions ◽  
Adaptation Process ◽  
Design Point ◽  
Component Map ◽  
Important Measurement ◽  
Unknown Component ◽  
Selection Of

The optimisation of engine performance by predictive means can help save cost and reduce environmental pollution. This can be achieved by developing a performance model which depicts the operating conditions of a given engine. Such models can also be used for diagnostic and prognostic purposes. Creating such models requires a method that can cope with the lack of component parameters and some important measurement data. This kind of method is said to be adaptive since it predicts unknown component parameters that match available target measurement data. In this paper an industrial aeroderivative gas turbine has been modelled at design and off-design points using an adaptation approach. At design point, a sensitivity analysis has been used to evaluate the relationships between the available target performance parameters and the unknown component parameters. This ensured the proper selection of parameters for the adaptation process which led to a minimisation of the adaptation error and a comprehensive prediction of the unknown component and available target parameters. At off-design point, the adaptation process predicted component map scaling factors necessary to match available off-design point performance data.

Control Proxy Functions for Sequential Design and Control Optimization

2011 ◽  
Vol 133 (9) ◽  
Author(s):  
Diane L. Peters ◽  
P. Y. Papalambros ◽  
A. G. Ulsoy
Keyword(s):  
Simultaneous Optimization ◽  
Sequential Optimization ◽  
Control Optimization ◽  
Smart Products ◽  
System Solution ◽  
Optimal System Design ◽  
Problem Formulations ◽  
And Control ◽  
Sequential Strategy ◽  
Selection Of

Optimal system design of “smart” products requires optimization of both the artifact and its controller. When the artifact and the controller designs are independent, the system solution is straightforward through sequential optimization. When the designs are coupled, combined simultaneous optimization can produce system-optimal results, but presents significant computational and organizational complexity. This paper presents a method that produces results comparable with those found with a simultaneous solution strategy, but with the simplicity of the sequential strategy. The artifact objective function is augmented by a control proxy function (CPF), representing the artifact’s ease of control. The key to successful use of this method is the selection of an appropriate CPF. Four theorems that govern the choice and evaluation of a CPF are given. Each theorem is illustrated using a simple mathematical example. Specific CPFs are then presented for particular problem formulations, and the method is applied to the optimal design and control of a micro-electrical mechanical system actuator.

scholarly journals Material Origins of Accelerated Operational Wear of RD-33 Engine Blades

2020 ◽  
Author(s):  
Adam Kozakiewicz ◽  
Stanislaw Jóźwiak ◽  
Przemysław Jóźwiak ◽  
Stanisław Kachel
Keyword(s):  
Chemical Composition ◽  
Construction Material ◽  
Operating Conditions ◽  
Design Stage ◽  
Strength Analysis ◽  
Jet Engine ◽  
Emergency Situations ◽  
Low Pressure Turbine ◽  
Propulsion Unit ◽  
Selection Of

The structural and strength analysis of the material used to construct such an important engine element as the turbine is of great significance, both at the design stage as well as during tests and expertises related to emergency situations. Bearing in mind the conditions above mentioned, the paper presents the results of research on the chemical composition, morphology and phased structure of the metallic construction material used to produce the blades of the high and low pressure turbine of the RD-33 jet engine, which is the propulsion unit of the MiG-29 aircraft. The data obtained as a result of the material tests of the blades allowed, on the basis of the analysis of chemical composition and phased structure, to determine the grade of the alloy used to construct the tested elements of the jet engine turbine. The structural stability of the material was found to be lower in comparison with engine operating conditions, which manifested itself as a clear decrease in the resistance properties of the blade material. The results obtained can be used as a basis for analyzing the life span of an object or a selection of material replacements, which enable to produce the analyzed engine element.

scholarly journals The Business Service Sector in India, Ireland and Poland. A Comparative Analysis

2019 ◽  
Vol 22 (2) ◽  
pp. 159-172
Author(s):  
Arkadiusz Mroczek
Keyword(s):  
Comparative Analysis ◽  
Service Sector ◽  
Operating Conditions ◽  
Business Service ◽  
Literature Study ◽  
Location Factors ◽  
Current Growth ◽  
Characteristic Features ◽  
Selection Of ◽  
Made In

The fast growth of the service sector is one of the characteristic features of the contemporary economy. Amongst other CEE countries, Poland is one of the emerging locations for this sector. The aim of the paper is to examine and compare the business service sector in India, Ireland and Poland. Both India and Ireland are exceptional locations for this industry, so comparing the state and operating conditions in Poland with those countries can be insightful. A literature study is used to determine the motives of companies undertaking offshore investments, upon which a selection of location factors is made. In the empirical part, those factors are analyzed in a descriptive way. This allows us to draw conclusions concerning this sector in Poland. This country, to some extent, possesses selected positive features of both India and Ireland, which explains the current growth of the sector.

scholarly journals Selection of efficient ships according to the criterion of marginal price at the feasibility study

2021 ◽  
pp. 172-181
Author(s):  
Oksana Y. Vasileva ◽  
Marina V. Nikulina Nikulina ◽  
Juri I. Platov Platov
Keyword(s):  
Fuel Consumption ◽  
Feasibility Study ◽  
Information Technologies ◽  
Optimization Methods ◽  
Relevant Information ◽  
Operating Conditions ◽  
Initial Stage ◽  
Level Of Use ◽  
High Level ◽  
Selection Of

The article deals with the problem of selecting efficient ships by the feasibility study in which brake power, main dimensions, payload, speed and fuel consumption are determined. The necessity of using the proposed selection at the initial stage of the ship's design is justified; the problems that arise at the present time are denoted. The purpose of the article is to propose a criterion for the selection of efficient vessels, "tied" to the operating conditions, based on the marginal cost of the ship. A method for its determination is presented. At the same time, annual revenues and operating costs should be determined by modern methods of business planning for the operation of the fleet. When searching for the parameters of the ship, the optimal fuel consumption is determined. The rest of the costs can be found according to the coefficients "tied" to the fuel consumption and calculated on the basis of existing prototypes. The results of calculations by the proposed method are shown; its merits and opportunities for improvement are noted with the availability of relevant information. The conclusion is made about the convenience and applicability of the proposed option for selecting efficient ship for the feasibility study based on optimization methods for determining the parameters of vessels under conditions of a high level of use of information technologies.

scholarly journals A Proposed New Approach for the Assessment of Selected Operating Conditions of the High Voltage Cable Line

Energies ◽  
2020 ◽  
Vol 13 (20) ◽  
pp. 5275
Author(s):  
Michał Borecki
Keyword(s):  
Correction Factor ◽  
External Environment ◽  
Extreme Temperature ◽  
Operating Conditions ◽  
Positive Temperature ◽  
Cable Line ◽  
Line System ◽  
New Approach ◽  
Selection Of ◽  
Calculation Models

Calculation models for the selection of cable lines used for expansion and modernization in the energy system and energy transmission planning are recognized tools supporting decision-making in both the energy sector and energy policy. At the same time, the above calculation models contain a large number of correction factors taking into account the temperature of the external environment at various points, the mutual influence of which is not taken into account. This means limitations to today’s common approaches to solutions, especially with regard to the required safety buffer for cable line selection. To meet this challenge, this article presents a parameter that takes into account the change and difference in temperature at various points in the external environment in the analyzed cable line systems. The purpose of this paper was to develop a new approach to the selection of a cable line in order to minimize failure during operation. For this purpose, possible temperature cases that may occur during line operation in different countries and at different rated voltages have been identified. Simulation models for individual cable line layouts were developed and the extreme temperature cases of the line operation for the maximum negative and positive temperature difference between the cable core and the external environment were considered in detail. The development of the curve of the change of the correction factor for the difference in the operating temperature of the cable line will allow for a more precise selection of the cable line parameters and the shortening of the current calculation model in terms of cable selection. In addition, this article presents a comparison of the change in the value of the correction factor from the change in temperature of a selected phase of a cable line system.

scholarly journals A GTCC-Based Underwater HMM Target Classifier with Fading Channel Compensation

2018 ◽  
Vol 2018 ◽  
pp. 1-14 ◽  
Author(s):  
Shameer K. Mohammed ◽  
Supriya M. Hariharan ◽  
Suraj Kamal
Keyword(s):  
Fading Channel ◽  
Rayleigh Fading ◽  
Automatic Target Recognition ◽  
Operating Conditions ◽  
Real Field ◽  
Classifier Performance ◽  
Acoustic Target ◽  
Artificial Neural Network Ann ◽  
Underwater Target ◽  
Selection Of

Underwater acoustic target classifiers are found to have many applications in military and security areas where a higher degree of prediction accuracy is needed that makes classifier efficiency and reliability an interesting subject. Classifiers are often trained with known acoustic target specimens with their characteristic feature set and tested with measurements obtained from the sonar that is deployed in the surveillance or observation zone. The selection of source-specific deterministic features in automatic target recognition (ATR) system is very significant, since it determines the reliability, efficiency, and success rate of the classifier. The robustness of the gammatone cepstral coefficients (GTCC) in combination with the statistical Euclidean distance, artificial neural network (ANN), and hidden Markov model (HMM) classifiers has been investigated, and its performance is compared with that of other feature extraction schemes. The classifier performance has been analyzed in Rayleigh fading conditions, based on which the performance is enhanced by incorporating an autoregressive (AR) Rayleigh fading channel compensation. The performance of the classifier in different operating conditions is investigated, with underwater target signals consisting of the real field data collected during expedition, and the results are presented in this paper.

Analysis on the Performance Characteristics of SOFC/GT Hybrid Systems Based on a Commercially Available MW-Class Gas Turbine

2005 ◽  
Author(s):  
Tae Won Song ◽  
Jeong L. Sohn ◽  
Tong Seop Kim ◽  
Sung Tack Ro
Keyword(s):  
Gas Turbine ◽  
Hybrid System ◽  
Guide Vane ◽  
Control Strategies ◽  
Operating Conditions ◽  
Performance Characteristics ◽  
Inlet Guide Vane ◽  
Part Load ◽  
Optimal Power ◽  
Selection Of

To investigate the possible applications of the SOFC/MGT hybrid system to large electric power generations, a study for the kW-class hybrid power system conducted in our group is extended to the MW-class hybrid system in this study. Because of the matured technology of the gas turbine and commercial availability in the market, it is reasonable to construct a hybrid system with the selection of a gas turbine as an off-the-shelf item. For this purpose, the performance analysis is conducted to find out the optimal power size of the hybrid system based on a commercially available gas turbine. The optimal power size has to be selected by considering specifications of a selected gas turbine which limit the performance of the hybrid system. Also, the cell temperature of the SOFC is another limiting parameter to be considered in the selection of the optimal power size. Because of different system configuration of the hybrid system, the control strategies for the part-load operation of the MW-class hybrid system are quite different from the kW-class case. Also, it is necessary to consider that the control of supplied air to the MW-class gas turbine is typically done by the variable inlet guide vane located in front of the compressor inlet, instead of the control of variable rotational speed of the kW-class micro gas turbine. Performance characteristics at part-load operating conditions with different kinds of control strategies of supplied fuel and air to the hybrid system are investigated in this study.

Vibration Based Condition Monitoring of Helicopter Gearboxes Based on Cyclostationary Analysis

2019 ◽  
Author(s):  
Alexandre Mauricio ◽  
Linghao Zhou ◽  
David Mba ◽  
Konstantinos Gryllias
Keyword(s):  
Experimental Tests ◽  
Operational Reliability ◽  
Health Condition ◽  
Operating Conditions ◽  
False Alarms ◽  
Complex Structures ◽  
Planetary Gearbox ◽  
Bearing Defects ◽  
Envelope Spectrum ◽  
Selection Of

Abstract The core of a helicopter drivetrain is a complex planetary main gearbox (MGB) which reduces the high input speed generated by the engines in order to provide the appropriate torque to the main rotors and to other auxiliary systems. The gearbox consists of various shafts, planetary gears and bearings and operates under varying conditions under excessive friction, heat and high mechanical forces. The components are vulnerable to fatigue defects and therefore Health and Usage Monitoring Systems (HUMS) have been developed in order to monitor the health condition of the gearbox, focusing towards early, accurate and on time fault detection with limited false alarms and missed detections. The main aim of a HUM System is by health monitoring to enhance the helicopters’ operational reliability, to support the maintenance decision making, and to reduce the overall maintenance costs. The importance and the need for more advanced and accurate HUMS have been emphasized recently by the post-accident analysis of the helicopter LN-OJF, which crashed in Norway in 2016. During the last few decades various methodologies and diagnostic indicators/features have been proposed for the monitoring of rotating machinery operating under steady conditions but still there is no global solution for complex structures. A new tool called IESFOgram has been recently proposed by the authors, based on Cyclostationary Analysis, focusing on the accurate selection of a filtering band, under steady and varying speed conditions. Moreover the Cyclic Spectral Coherence is integrated along the selected frequency band leading to an Improved Envelope Spectrum. In this paper the performance of the tool is tested on a complex planetary gearbox, with several vibration sources. The method is tested, evaluated and compared to state of the art methods on a dataset captured during experimental tests under various operating conditions on a Category A Super Puma SA330 main planetary gearbox, presenting seeded bearing defects of different sizes.

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