scholarly journals A Methodological Approach to Assessment and Reporting of the Model Adequacy in Simulation Studies

Author(s):  
Michael Sony ◽  
V. Marriapan

Assessment and Reporting of Model Adequacy is an important step in the simulation modelling process. It stipulates the level of precision and accuracy, which are important features of the model predictions. In an academic research activity, an important step for model development is the process of the identification or accepting whether the model is wrong. The evaluation of the adequacy of developed models is not possible through a single statistical test. This paper delineates a technique to implement model adequacy. A live case is demonstrated on the proposed methodology by evaluating a simulation model which was designed by us to simulate a well-established mathematical model. A step by step methodological approach is delineated in this paper along with a case study of investigation of a simulation model with a mathematical model is used to demonstrate this methodology. The paper concludes with an Algorithm and a flow chart for performing model adequacy for assessing the adequacy of the developed model with existing models.

Assessment and Reporting of Model Adequacy is an important step in the simulation modelling process. It stipulates the level of precision and accuracy, which are important features of the model predictions. In an academic research activity, an important step for model development is the process of the identification or accepting whether the model is wrong. The evaluation of the adequacy of developed models is not possible through a single statistical test. This paper delineates a technique to implement model adequacy. A live case is demonstrated on the proposed methodology by evaluating a simulation model which was designed by us to simulate a well-established mathematical model. A step by step methodological approach is delineated in this paper along with a case study of investigation of a simulation model with a mathematical model is used to demonstrate this methodology. The paper concludes with an Algorithm and a flow chart for performing model adequacy for assessing the adequacy of the developed model with existing models.


Author(s):  
Dumitru Cernelev ◽  
Allan Chegus ◽  
Frank Lin

The problem of identifying and removing bottlenecks in a multi-terminal oil & gas pipeline network while achieving quality and delivery targets is a very real and complex problem. The most effective way to meet the above business objective is to develop a terminal network simulation model. This paper is a case study describing the approach in designing a complex multi-nodal pipeline network simulation model with objective to resolve a critical inter-company storage problem for a major refiner. Various complex system modeling techniques and approaches are elaborated with a focus on practical application. A case study is also presented to demonstrate the practical application of the modeling techniques for terminal network simulation model development.


2021 ◽  
Author(s):  
Janka Saderova ◽  
Andrea Rosova ◽  
Annamaria Behunova ◽  
Marcel Behun ◽  
Marian Sofranko ◽  
...  

AbstractThe paper deals with the simulation of selected activities in the warehouse. Routine logistics activities are the receipt of the goods, the control of the goods, and the goods’ storage in the warehousing system on the side of the entry into the warehouse. On the output side, these are activities such as picking, packing and shipping. The economy of warehouse operations depends on the efficiency of the logistics activities performed and on deployed the technical means. The paper’s main goal is to present a created simulation model for a selected warehouse activity—receipt of goods into the warehouse. This operation involves unloading the goods from the trucks, moving them to the physical receipt, where the quantitative and qualitative control of the goods is performed (acceptance of goods). An analysis of this activity preceded the creation of the simulation model under operating conditions. The research was performed by observing and measuring the forklift’s work cycle, which unloaded pallets from the trucks. The obtained data from the analysis were the input to the simulation model. The EXTENDSIM8 simulation system was used to create a simulation model. The several experiments were performed on the model after its creating and verifying the functionality. The paper evaluates 3 experiments and analyzes their results. The main benefit, novelty, of the article is the simulation of a selected activity for a specific company’s conditions. The experiments results are a reasonable basis for the creation of an operational tool for the company.


Author(s):  
I. I. Kravchenko

The paper considers the mathematical model development technique to build a vector field of the shape deviations when machining flat surfaces of shell parts on multi-operational machines under conditions of anisotropic rigidity in technological system (TS). The technological system has an anisotropic rigidity, as its elastic strains do not obey the accepted concepts, i.e. the rigidity towards the coordinate axes of the machine is the same, and they occur only towards the external force. The record shows that the diagrams of elastic strains of machine units are substantially different from the circumference. The issues to ensure the specified accuracy require that there should be mathematical models describing kinematic models and physical processes of mechanical machining under conditions of the specific TS. There are such models for external and internal surfaces of rotation [2,3], which are successfully implemented in practice. Flat surfaces (FS) of shell parts (SP) are both assembly and processing datum surfaces. Therefore, on them special stipulations are made regarding deviations of shape and mutual arrangement. The axes of the main bearing holes are coordinated with respect to them. The joints that ensure leak tightness and distributed load on the product part are closed on these surfaces. The paper deals with the analytical construction of the vector field F, which describes with appropriate approximation the real surface obtained as a result of modeling the process of machining flat surfaces (MFS) through face milling under conditions of anisotropic properties.


2008 ◽  
Vol 59 (10) ◽  
Author(s):  
Delia Perju ◽  
Harieta Pirlea ◽  
Gabriela-Alina Brusturean ◽  
Dana Silaghi-Perju ◽  
Sorin Marinescu

The European laws and recently the Romanian ones impose more and more strict norms to the large nitrogen dioxide polluters. They are obligated to continuously improve the installations and products so that they limit and reduce the nitrogen dioxide pollution, because it has negative effects on the human health and environment. In this paper are presented these researches made within a case study for the Timi�oara municipality, regarding the modeling and simulation of the nitrogen dioxide dispersion phenomenon coming from various sources in atmosphere with the help of analytical-experimental methods. The mathematical model resulting from these researches is accurately enough to describe the real situation. This was confirmed by comparing the results obtained based on the model with real experimental values.


2013 ◽  
Vol 3 (2) ◽  
pp. 79-95
Author(s):  
Zuzana Vlachová

The paper presents a qualitative empirical research project, research design and research methods used in the preparation of a dissertation which deals with music therapy interventions in children with autism. The reason for examining this issue is a considerable lack of research activity in this area, and thus also a lack of relevant results on which clinical practice could rely. The results of future investigations should bring answers to the question of how children with autism receive and experience music therapy intervention and also what the effect of music therapy intervention in the social interaction of children is; research will be directed to a deeper understanding of this influence and its characteristics using the multiple case study design.


2019 ◽  
Vol 9 (1) ◽  
pp. 65-93 ◽  
Author(s):  
Alberto Arenal ◽  
Claudio Feijoo ◽  
Ana Moreno ◽  
Cristina Armuña ◽  
Sergio Ramos

Purpose Academic research into entrepreneurship policy is particularly interesting due to the increasing relevance of the topic and since knowledge about the evolution of themes in this field is still rather limited. The purpose of this paper is to analyse the key concepts, topics, trends and shifts that have shaped the entrepreneurship policy research agenda during the period 1990–2016. Design/methodology/approach This paper uses text mining techniques, cluster analysis and complementary bibliographic data to examine the evolution of a corpus of 1,048 academic papers focused on entrepreneurship-related policies and published during the period 1990–2016 in ten relevant journals. In particular, the paper follows a standard text mining workflow: first, as text is unstructured, content requires a set of pre-processing tasks and then a stemming process. Then, the paper examines the most repeated concepts within the corpus, considering the whole period 1990–2016 and also in five-year terms. Finally, the paper conducts a k-means clustering to divide the collection of documents into coherent groups with similar content. The analyses in the paper also include geographical particularities considering three regional sub-corpora, distinguishing those articles authored in the European Union (EU), the USA and South and Eastern Asia, respectively. Findings Results of the analysis show that inclusion, employment and regulation-related papers have largely dominated the research in the field, evolving from an initial classical approach to the relationship between entrepreneurship and employment to a wider, multidisciplinary perspective, including the relevance of management, geographies and narrower topics such as agglomeration economics or internationalisation instead of the previous generic sectorial approaches. The text mining analysis also reveals how entrepreneurship policy research has gained increasing attention and has become both more open, with a growing cooperation among researchers from different affiliations, and more sophisticated, with concepts and themes that moved the research agenda forward, closer to the priorities of policy implementation. Research limitations/implications The paper identifies main trends and research gaps in the field of entrepreneurship policy providing actionable knowledge by presenting the spectrum of both over-explored and understudied research themes in the field. In practical terms the results of the text mining analysis can be interpreted as a compass to navigate the entrepreneurship policy research agenda. Practical implications The paper presents the heterogeneity of topics under research in the field, reinforcing the concept of entrepreneurship as a multidisciplinary and dynamic domain. Therefore, the definition and adoption of a certain policy agenda in entrepreneurship should consider multiple aspects (needs, objectives, stakeholders, expected outputs, etc.) to be comprehensive and aligned with its complexity. In addition, the paper shows how text mining techniques could be used to map the research activity in a particular field, contributing to the challenge of linking research and policy. Originality/value The exploratory nature of text mining allows us to obtain new knowledge and reveals hidden patterns from large quantities of documents/text data, representing an opportunity to complement other qualitative reviews. In this sense, the main value of this paper is not to advise on the future configuration of entrepreneurship policy as a research topic, but to unwrap the past by unveiling how key themes of the entrepreneurship policy research agenda have emerged, evolved and/or declined over time as a foundation on which to build further developments.


Solar Energy ◽  
2017 ◽  
Vol 146 ◽  
pp. 264-275 ◽  
Author(s):  
Laura Romero Rodríguez ◽  
Eric Duminil ◽  
José Sánchez Ramos ◽  
Ursula Eicker

Sign in / Sign up

Export Citation Format

Share Document