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Abstract

The article discusses the weldment to casting conversion process of rocker arm designed for operation in a special purpose vehicle to

obtain a consistency of objective functions, which assume the reduced weight of component, the reduced maximum effort of material

under the impact of service loads achieved through topology modification for optimum strength distribution in the sensitive areas, and the

development of rocker arm manufacturing technology. As a result of conducted studies, the unit weight of the item was reduced by 25%,

and the stress limit values were reduced to a level guaranteeing safe application.

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Authors and Affiliations

M. Maj
S. Pysz
R. Żuczek
J. Piekło
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Abstract

It has been found that the area where one can look for significant reserves in the procurement logistics is a rational management

of the stock of raw materials. Currently, the main purpose of projects which increase the efficiency of inventory management is to

rationalise all the activities in this area, taking into account and minimising at the same time the total inventory costs. The paper presents

a method for optimising the inventory level of raw materials under a foundry plant conditions using two different control models. The first

model is based on the estimate of an optimal level of the minimum emergency stock of raw materials, giving information about the need

for an order to be placed immediately and about the optimal size of consignments ordered after the minimum emergency level has

occurred. The second model is based on the estimate of a maximum inventory level of raw materials and an optimal order cycle.

Optimisation of the presented models has been based on the previously done selection and use of rational methods for forecasting the time

series of the delivery of a chosen auxiliary material (ceramic filters) to a casting plant, including forecasting a mean size of the delivered

batch of products and its standard deviation

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Authors and Affiliations

K. Nowacki
J. Szymszal
T. Lis
J. Przondziono
J. Kliś
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Abstract

A comparative analysis involving the evaluation of the effectiveness of investment projects can be based on various rules indicating

selection of the most favorable decisions. The dynamic methods for assessment of investment projects discussed in this article, which

consider the possibility of modifying the predetermined investment options, are quite complex and difficult to implement. They are used

both in the construction phase of the new company, as well as in its subsequent modernization. The assessments should be characterized

by a high coefficient of the economic efficiency. The, observed in practice, high dynamic variability of both the external and internal

conditions under which the company operates is the reason why in the process of calculating the economic efficiency of investment

projects, there is a significant number of random parameters affected by high uncertainty and risk. Investments in the metallurgical

industry are characterized by a relatively long cycle of implementation and operation. These are capital-intensive projects and often

mistakenly taken investment decisions end in failure of the investment project and, consequently, in the collapse of the company. In

addition, the applied methods of risk assessment of investment projects, especially the dynamic ones, should be fully understood by

managerial staff and constitute an easy to use, yet accurate tool for improving the efficiency of the company.

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Authors and Affiliations

J. Szymszal
T. Lis
B. Gajdzik
J. Kliś
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Abstract

The paper undertakes an important topic of evaluation of effectiveness of SCADA (Supervisory Control and Data Acquisition) systems,

used for monitoring and control of selected processing parameters of classic green sands used in foundry. Main focus was put on process

studies of properties of so-called 1st generation molding sands in the respect of their preparation process. Possible methods of control of

this processing are presented, with consideration of application of fresh raw materials, return sand (regenerate) and water. The studies

conducted in one of European foundries were aimed at pointing out how much application of new, automated plant of sand processing

incorporating the SCADA systems allows stabilizing results of measurement of selected sand parameters after its mixing. The studies

concerned two comparative periods of time, before an implementation of the automated devices for green sands processing (ASMS -

Automatic Sand Measurement System and MCM – Main Control Module) and after the implementation. Results of measurement of

selected sand properties after implementation of the ASMS were also evaluated and compared with testing studies conducted periodically

in laboratory.

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Authors and Affiliations

Z. Ignaszak
J. Kozłowski
M. Perzyk
R. Sika
A. Kochański
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Abstract

Conducting reliable and credible evaluation and statistical interpretation of empirical results related to the operation of production systems

in foundries is for most managers complicated and labour-intensive. Additionally, in many cases, statistical evaluation is either ignored

and considered a necessary evil, or is completely useless because of improper selection of methods and subsequent misinterpretation of the

results. In this article, after discussing the key elements necessary for the proper selection of statistical methods, a wide spectrum of these

methods has been presented, including regression analysis, uni- and multivariate correlation, one-way analysis of variance for factorial

designs, and selected forecasting methods. Each statistical method has been illustrated with numerous examples related to the foundry

practice.

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Authors and Affiliations

J. Szymszal
B. Gajdzik
G. Kaczmarczyk
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Abstract

The objective of studies presented in this publication was structuring of research knowledge about the ADI functional properties and

changes in these properties due to material treatment. The results obtained were an outcome of research on the selection of a format of

knowledge representation that would be useful in further work aiming at the design, application and implementation of an effective system

supporting the decisions of a technologist concerning the choice of a suitable material (ADI in this case) and appropriate treatment process

(if necessary). ALSV(FD) logic allows easy modelling of knowledge, which should let addressees of the target system carry out

knowledge modelling by themselves. The expressiveness of ALSV (FD) logic allows recording the values of attributes from the scope of

the modelled domain regarding ADI, which is undoubtedly an advantage in the context of further use of the logic. Yet, although the logic

by itself does not allow creating the rules of knowledge, it may form a basis for the XTT format that is rule-based notation. The difficulty

in the use of XTT format for knowledge modelling is acceptable, but formalism is not suitable for the discovery of rules, and therefore the

knowledge of technologist is required to determine the impact of process parameters on values that are functional properties of ADI. The

characteristics of ALSV(FD) logic and XTT formalism, described in this article, cover the most important aspects of a broadly discussed,

full evaluation of the applicability of these solutions in the construction of a system supporting the decisions of a technologist.

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Authors and Affiliations

S. Kluska-Nawarecka
K. Regulski
G. Rojek
D. Wilk-Kołodziejczyk
W.T. Adrian

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