Comparison of different vector Preisach models for the simulation of ferromagnetic materials

2019 ◽  
Vol 38 (5) ◽  
pp. 1696-1710
Author(s):  
Michael Nierla ◽  
Michael Loeffler ◽  
Manfred Kaltenbacher ◽  
Stefan Johann Rupitsch
Keyword(s):  
Computational Time ◽  
Preisach Model ◽  
Practical Application ◽  
Content Type ◽  
Computational Costs ◽  
Evaluation Approach ◽  
The Cost ◽  
And Inversion ◽  
Magnetization Processes ◽  
Rotational Operator

Purpose The numerical computation of magnetization processes in moving and rotating assemblies requires the usage of vector hysteresis models. A commonly used model is the so-called Mayergoyz vector Preisach model, which applies the scalar Preisach model into multiple angles of the halfspace. The usage of several scalar models, which are optionally weighted differently, enables the description of isotropic as well as anisotropic materials. The flexibility is achieved, however, at the cost of multiple scalar model evaluations. For solely isotropic materials, two vector Preisach models, based on an extra rotational operator, might offer a lightweight alternative in terms of evaluation cost. The study aims at comparing the three mentioned models with respect to computational efficiency and practical applicability. Design/methodology/approach The three mentioned vector Preisach models are compared with respect to their computational costs and their representation of magnetic polarization curves measured by a vector vibrating sample magnetometer. Findings The results prove the applicability of all three models to practical scenarios and show the higher efficiency of the vector models based on rotational operators in terms of computational time. Originality/value Although the two vector Preisach models, based on an extra rotational operator, have been proposed in 2012 and 2015, their practical application and inversion has not been tested yet. This paper not only shows the usability of these particular vector Preisach models but also proves the efficiency of a special stageless evaluation approach that was proposed in a former contribution.

Stageless evaluation for a vector Preisach model based on rotational operators

2017 ◽  
Vol 36 (5) ◽  
pp. 1501-1516
Author(s):  
Michael Nierla ◽  
Alexander Sutor ◽  
Stefan Johann Rupitsch ◽  
Manfred Kaltenbacher
Keyword(s):  
Design Methodology ◽  
Computational Cost ◽  
Direct Application ◽  
Preisach Model ◽  
Machine Precision ◽  
Content Type ◽  
Model Based ◽  
Evaluation Scheme ◽  
Computational Resources ◽  
Rotational Operator

Purpose This paper aims to present a novel stageless evaluation scheme for a vector Preisach model that exploits rotational operators for the description of vector hysteresis. It is meant to resolve the discretizational errors that arise during the application of the standard matrix-based implementation of Preisach-based models. Design/methodology/approach The newly developed evaluation uses a nested-list data structure. Together with an adapted form of the Everett function, it allows to represent both the additional rotational operator and the switching operator of the standard scalar Preisach model in a stageless fashion, i.e. without introducing discretization errors. Additionally, presented updating and simplification rules ensure the computational efficiency of the scheme. Findings A comparison between the stageless evaluation scheme and the commonly used matrix approach reveals not only an improvement in accuracy up to machine precision but, furthermore, a reduction of computational resources. Research limitations/implications The presented evaluation scheme is especially designed for a vector Preisach model, which is based on an additional rotational operator. A direct application to other vector Preisach models that do not rely on rotational operators is not intended. Nevertheless, the presented methodology allows an easy adaption to similar vector Preisach schemes that use modified setting rules for the rotational operator and/or the switching operator. Originality/value Prior to this contribution, the vector Preisach model based on rotational operators could only be evaluated using a matrix-based approach that works with discretized forms of rotational and switching operator. The presented evaluation scheme offers reduced computational cost at much higher accuracy. Therefore, it is of great interest for all users of the mentioned or similar vector Preisach models.

Forklift truck performance simulation and fuel consumption estimation

2019 ◽  
Vol 18 (3) ◽  
pp. 689-703
Author(s):  
Luigi d'Apolito ◽  
Hanchi Hong
Keyword(s):  
Fuel Consumption ◽  
Experimental Tests ◽  
Computational Time ◽  
Large Set ◽  
Performance Simulation ◽  
Content Type ◽  
Driving Cycles ◽  
The Cost ◽  
Avl Cruise ◽  
Load Handling

Purpose Forklift trucks are generally operated with frequent accelerations and stops, reverse and operations of load handling. This way of operation increases the energy losses and consequently the need for reduction of fuel consumption from forklift customers. This study aims to build a model to replicate the performance of forklifts during real operations and estimate fuel consumption without building a real prototype. Design/methodology/approach AVL Cruise has been used to simulate forklift powertrain and hydraulic circuit. The driving cycles used for this study were in accordance with the standard VDI 2198. Artificial neural networks (ANNs), trained by the results of AVL Cruise simulations, have been used to forecast the fuel consumption for a large set of possible driving cycles. Findings The comparison between simulated and experimental data verified that AVL Cruise model was able to simulate the performance of real forklifts, but the results were only valid for the specified driving cycle. The ANNs, trained by the results of AVL Cruise for a certain number of driving cycles, have been found effective to forecast the fuel consumption of a larger number of driving cycles following the prescriptions of the standard VDI 2198. Originality/value A new method based on ANN, trained by AVL Cruise simulation results, has been introduced to forecast the forklift fuel consumption, reducing the computational time and the cost of experimental tests.

Multi-objective design optimization of hybrid renewable systems using UGF

2015 ◽  
Vol 34 (6) ◽  
pp. 1825-1844 ◽  
Author(s):  
Carmen Delgado ◽  
José Antonio Domínguez-Navarro
Keyword(s):  
State Model ◽  
Computational Time ◽  
Renewable Generation ◽  
Multi Objective Optimization ◽  
Generation System ◽  
Hybrid Generation ◽  
Content Type ◽  
Multi Objective ◽  
The Cost ◽  
The Impact

Purpose – Renewable generation is a main component of most hybrid generation systems. However, randomness on its generation is a characteristic to be considered due to its direct impact on reliability and performance of these systems. For this reason, renewable generation usually is accompanied with other generation elements to improve their general performance. The purpose of this paper is to analyze the power generation system, composed of solar, wind and diesel generation and power outsourcing option from the grid as means of reserve source. A multi-objective optimization for the design of hybrid generation system is proposed, particularly using the cost of energy, two different reliability indexes and the percentage of renewable energy as objectives. Further, the uncertainty of renewable sources and demand is modeled with a new technique that permits to evaluate the reliability quickly. Design/methodology/approach – The multi-state model of the generators and the load is modeled with the Universal Generating Function (UGF) to estimate the reliability indexes for the whole system. Then an evolutionary algorithm NSGA-II (Non-dominated Sorting Genetic Algorithm) is used to solve the multi-objective optimization model. Findings – The use of UGF methodology reduces the computation time, providing effective results. The validation of reliability assessment of hybrid generation systems using the UGF is carried out taking as a benchmark the results obtained with the Monte Carlo simulation. The proposed multi-objective algorithm gives as a result different generators combinations that outline hybrid systems, where some of them could be preferred over others depending on its results for each independent objective. Also it allows us to observe the changes produced on the resulting solutions due to the impact of the power fluctuation of the renewable generators. Originality/value – The main contributions of this paper are: an extended multi state model that includes different types of renewable energies, with emphasis on modeling of solar energy; demonstrate the performance improvement of UGF against SMC regarding the computational time required for this case; test the impact of different multi-states numbers for the representation of the elements; depict through multi-objective optimization, the impact of combining different energies on the cost and reliability of the resultant systems.

The cost-effectiveness of insulin analogs and regular insulin for diabetes control: a case study in Iran

2020 ◽  
Vol 33 (4/5) ◽  
pp. 323-331
Author(s):  
Mohsen pakdaman ◽  
Raheleh akbari ◽  
Hamid reza Dehghan ◽  
Asra Asgharzadeh ◽  
Mahdieh Namayandeh
Keyword(s):  
Cost Effectiveness ◽  
Cost Effective ◽  
Regular Insulin ◽  
Diabetes Control ◽  
Diabetic Patients ◽  
Insulin Analogs ◽  
Content Type ◽  
Patients With Diabetes ◽  
The Government ◽  
The Cost

PurposeFor years, traditional techniques have been used for diabetes treatment. There are two major types of insulin: insulin analogs and regular insulin. Insulin analogs are similar to regular insulin and lead to changes in pharmacokinetic and pharmacodynamic properties. The purpose of the present research was to determine the cost-effectiveness of insulin analogs versus regular insulin for diabetes control in Yazd Diabetes Center in 2017.Design/methodology/approachIn this descriptive–analytical research, the cost-effectiveness index was used to compare insulin analogs and regular insulin (pen/vial) for treatment of diabetes. Data were analyzed in the TreeAge Software and a decision tree was constructed. A 10% discount rate was used for ICER sensitivity analysis. Cost-effectiveness was examined from a provider's perspective.FindingsQALY was calculated to be 0.2 for diabetic patients using insulin analogs and 0.05 for those using regular insulin. The average cost was $3.228 for analog users and $1.826 for regular insulin users. An ICER of $0.093506/QALY was obtained. The present findings suggest that insulin analogs are more cost-effective than regular insulin.Originality/valueThis study was conducted using a cost-effectiveness analysis to evaluate insulin analogs versus regular insulin in controlling diabetes. The results of study are helpful to the government to allocate more resources to apply the cost-effective method of the treatment and to protect patients with diabetes from the high cost of treatment.

scholarly journals Simulation of Thermal and Electric Field Distribution in Packaged Sausages Heated in a Stationary Versus a Rotating Microwave Oven

Foods ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 1622
Author(s):  
Wipawee Tepnatim ◽  
Witchuda Daud ◽  
Pitiya Kamonpatana
Keyword(s):  
Temperature Distribution ◽  
Electric Field ◽  
Three Dimensional ◽  
Development Stage ◽  
Microwave Oven ◽  
Computational Time ◽  
Plastic Package ◽  
Heating Uniformity ◽  
The Cost ◽  
Good Agreement

The microwave oven has become a standard appliance to reheat or cook meals in households and convenience stores. However, the main problem of microwave heating is the non-uniform temperature distribution, which may affect food quality and health safety. A three-dimensional mathematical model was developed to simulate the temperature distribution of four ready-to-eat sausages in a plastic package in a stationary versus a rotating microwave oven, and the model was validated experimentally. COMSOL software was applied to predict sausage temperatures at different orientations for the stationary microwave model, whereas COMSOL and COMSOL in combination with MATLAB software were used for a rotating microwave model. A sausage orientation at 135° with the waveguide was similar to that using the rotating microwave model regarding uniform thermal and electric field distributions. Both rotating models provided good agreement between the predicted and actual values and had greater precision than the stationary model. In addition, the computational time using COMSOL in combination with MATLAB was reduced by 60% compared to COMSOL alone. Consequently, the models could assist food producers and associations in designing packaging materials to prevent leakage of the packaging compound, developing new products and applications to improve product heating uniformity, and reducing the cost and time of the research and development stage.

The 4Cs of mass customization in service industries: a customer lens

2020 ◽  
Vol 34 (4) ◽  
pp. 499-511 ◽  
Author(s):  
Jessica L. Pallant ◽  
Sean Sands ◽  
Ingo Oswald Karpen
Keyword(s):  
Boundary Conditions ◽  
Mass Customization ◽  
Design Methodology ◽  
Service Industries ◽  
Future Research ◽  
Practical Application ◽  
Theoretical Understanding ◽  
Content Type ◽  
Priority Areas ◽  
Research Priority

Purpose Increasingly, customers are demanding products that fit their individual needs. Many firms respond by cultivating product individualization via mass customization, often integrating this capability via interactive platforms that connect them with customers. Despite such customization, research to date has lacked cohesion, often taking the organizational, rather than customer, view. The purpose of this paper is to provide inconclusive theorizing in regard to customization from the consumers’ perspective. Design/methodology/approach The review and synthesis of the literature revealed that co-configuration is an underexplored domain of mass customization. Consequently, an initial conceptualization of co-configuration is developed and compared with current customization strategies. Specifically, the definition and boundary conditions of co-configuration are compared with three domains of mass customization, namely, co-production, co-construction and co-design. This led to the development of research priority areas to establish an agenda for future research on mass customization and its role in customer’ firm relationships. Findings This paper provides the delineation of four distinct consumer customization strategies, conceptualized in a matrix, and proposes separate customer journey visualizations. In advancing the theoretical understanding by means of a unifying typology, this paper identifies three existing Cs of mass customization (co-production, co-construction and co-design) and focuses specifically on a fourth (co-configuration), identified as an understudied mass customization strategy. Originality/value This paper extends the previous conceptualizations of mass customization comprising co-production, co-design and co-construction. The proposed typology establishes a foundation for four research priority areas that can improve both academic rigor and practical application.

Evaluating the cost and benefits of earthquake protection of buildings

2018 ◽  
Vol 11 (2) ◽  
pp. 263-278 ◽  
Author(s):  
Benedetto Manganelli ◽  
Marco Vona ◽  
Pierfrancesco De Paola
Keyword(s):  
Real Estate ◽  
Seismic Risk ◽  
Risk Mitigation ◽  
Tax Incentives ◽  
Seismic Retrofitting ◽  
Content Type ◽  
Seismic Risk Mitigation ◽  
The Cost ◽  
Earthquake Protection ◽  
Real Estate Assets

Purpose The purpose of this study is the evaluation of the cost and benefits of earthquake protection of buildings to verify whether the legislative push, through tax incentives, will produce results and lead to a redevelopment of private real estate assets. Design/methodology/approach Through contingent valuation, this research aims to measure the propensity of homeowners to invest in the seismic security of their properties. The sample of homeowners was selected in a southern Italy city, which was characterized by a medium-high seismic hazard. The willingness to pay, once made independent from the family income, was compared with the actual cost of a seismic retrofitting technique to assess its cost-effectiveness. Findings The analysis developed on an example case shows that the economic sustainability of the intervention is only verified when considering the current tax incentives for this type of intervention. Practical implications Choosing to introduce a system to compulsory insurance against seismic risk could certainly be a strong incentive for the implementation of retrofitting interventions on private real estate assets. In this direction, investigations like this can be fundamental to establish the fair risk premium. Originality/value The need for effective seismic risk mitigation policies is also based on the growing awareness of the, often fatal, effects of seismic events, emphasized by the recent medium and high intensity events that hit Italy. The issue of the security of residential buildings is therefore a very topical issue in view of their high seismic vulnerability and the vast number of buildings requiring major seismic retrofitting. Therefore, the propensity of owners to intervene in improving the seismic performance of their properties can be crucial in seismic risk mitigation.

The impact of labor freedom on geographic cost of living differentials

2017 ◽  
Vol 6 (3) ◽  
pp. 385-395
Author(s):  
Richard Cebula ◽  
James E. Payne ◽  
Donnie Horner ◽  
Robert Boylan
Keyword(s):  
Labor Market ◽  
State Level ◽  
The State ◽  
Annual Data ◽  
Significant Finding ◽  
Cost Of Living ◽  
Content Type ◽  
The Usa ◽  
The Cost ◽  
The Impact

Purpose The purpose of this paper is to examine the impact of labor market freedom on state-level cost of living differentials in the USA using cross-sectional data for 2016 after allowing for the impacts of economic and quality of life factors. Design/methodology/approach The study uses two-stage least squares estimation controlling for factors contributing to cost of living differences across states. Findings The results reveal that an increase in labor market freedom reduces the overall cost of living. Research limitations/implications The study can be extended using panel data and alternative measures of labor market freedom. Practical implications In general, the finding that less intrusive government and greater labor freedom are associated with a reduced cost of living should not be surprising. This is because less government intrusion and greater labor freedom both inherently allow markets to be more efficient in the rationalization of and interplay with forces of supply and demand. Social implications The findings of this and future related studies could prove very useful to policy makers and entrepreneurs, as well as small business owners and public corporations of all sizes – particularly those considering either location in, relocation to, or expansion into other markets within the USA. Furthermore, the potential benefits of the National Right-to-Work Law currently under consideration in Congress could add cost of living reductions to the debate. Originality/value The authors extend the literature on cost of living differentials by investigating whether higher amounts of state-level labor market freedom act to reduce the states’ cost of living using the most recent annual data available (2016). That labor freedom has a systemic efficiency impact on the state-level cost of living is a significant finding. In our opinion, it is likely that labor market freedom is increasing the efficiency of labor market transactions in the production and distribution of goods and services, and acts to reduce the cost of living in states. In addition, unlike previous related studies, the authors investigate the impact of not only overall labor market freedom on the state-level cost of living, but also how the three sub-indices of labor market freedom, as identified and measured by Stansel et al. (2014, 2015), impact the cost of living state by state.

The generation of adaptive assembly from predicting change propagation

2015 ◽  
Vol 35 (3) ◽  
pp. 269-280 ◽  
Author(s):  
Hu Qiao ◽  
Rong Mo ◽  
Ying Xiang
Keyword(s):  
Computer Aided Design ◽  
Three Dimensional ◽  
Original Method ◽  
Change Propagation ◽  
Assembly Model ◽  
Practical Application ◽  
Content Type ◽  
Design Structure ◽  
Aided Design ◽  
Practical Implications

Purpose – The purpose of this paper is to establish an adaptive assembly, to realize the adaptive changing of the models and to improve the flexibility and reliability of assembly change. For a three-dimensional (3D) computer-aided design (CAD) assembly in a changing process, there are two practical problems. One is delivering parameters’ information not smoothly. The other one is to easily destroy an assembly structure. Design/methodology/approach – The paper establishes associated parameters design structure matrix of related parts, and predicts possible propagation paths of the parameters. Based on the predicted path, structured storage is made for the affected parameters, tolerance range and the calculation relations. The study combines structured path information and all constrained assemblies to build the adaptive assembly, proposes an adaptive change algorithm for assembly changing and discusses the extendibility of the adaptive assembly. Findings – The approach would improve the flexibility and reliability of assembly change and be applied to different CAD platform. Practical implications – The examples illustrate the construction and adaptive behavior of the assembly and verify the feasibility and reasonability of the adaptive assembly in practical application. Originality/value – The adaptive assembly model proposed in the paper is an original method to assembly change. And compared with other methods, good results have been obtained.

A nonlinear magnetic circuit model for periodic eddy current problems using T,ϕ-ϕ formulation

2017 ◽  
Vol 36 (3) ◽  
pp. 649-664 ◽  
Author(s):  
Rene Plasser ◽  
Gergely Koczka ◽  
Oszkár Bíró
Keyword(s):  
Eddy Current ◽  
Magnetic Circuit ◽  
Iteration Process ◽  
Equation System ◽  
Circuit Model ◽  
Computational Time ◽  
Combined Method ◽  
3D Fem ◽  
Content Type ◽  
Transformer Model

Purpose A transformer model is used as a benchmark for testing various methods to solve 3D nonlinear periodic eddy current problems. This paper aims to set up a nonlinear magnetic circuit problem to assess the solving procedure of the nonlinear equation system for determining the influence of various special techniques on the convergence of nonlinear iterations and hence the computational time. Design/methodology/approach Using the T,ϕ-ϕ formulation and the harmonic balance fixed-point approach, two techniques are investigated: the so-called “separate method” and the “combined method” for solving the equation system. When using the finite element method (FEM), the elapsed time for solving a problem is dominated by the conjugate gradient (CG) iteration process. The motivation for treating the equations of the voltage excitations separately from the rest of the equation system is to achieve a better-conditioned matrix system to determine the field quantities and hence a faster convergence of the CG process. Findings In fact, both methods are suitable for nonlinear computation, and for comparing the final results, the methods are equally good. Applying the combined method, the number of iterations to be executed to achieve a meaningful result is considerably less than using the separated method. Originality/value To facilitate a quick analysis, a simplified magnetic circuit model of the 3D problem was generated to assess how the different ways of solutions will affect the full 3D solving process. This investigation of a simple magnetic circuit problem to evaluate the benefits of computational methods provides the basis for considering this formulation in a 3D-FEM code for further investigation.

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