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1

Modelling the Natural Gas Transportation Process using the Factorial Experiment Method

Țîțu Aurel Mihail, Pop Alina Bianca, Nabiałek Marcin

Archives of Metallurgy and Materials

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2023

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Vol. 68, iss. 3

961--966

EN

The research presented in detail in this scientific paper refers to the modelling of process parameters for natural gas transmission in a centralized system. The method of the factorial experiment was used to model some parameters considered to be vital, namely the gas temperature, the air temperature as well as a certain correction factor on the flow delivered to the population. The study was conducted by accessing information provided by a regulation-measurement station that delivers gas to an important locality in a locality in central Romania. Experimental data collected over 24 hours on a summer day but also on a winter day were used. After a previous study with classical experimental research methods, the factorial experiment was used, which allows the delivery of much more detailed information and the graphical representations are much more precise and detailed, in other words, relevant and useful conclusions can be obtained on objective studied in the research approached.

2

Development of Turboshaft Engine Adaptive Dynamic Model: Analysis of Estimation Errors

Yepifanov Sergiy, Bondarenko Oleksiy

Transactions on Aerospace Research

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2022

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Nr 4 (269)

59--71

EN

One of the most perspective directions of aircraft engine development is related to implementing adaptive automatic electronic control systems (ACS). The significant elements of these systems are algorithms of matching of mathematical models to actual performances of the engine. These adaptive models are used directly in control algorithms and are a combination of static and dynamic sub-models. This work considers the dynamic sub-models formation using the Least Square method (LSM) on a base of the engine parameters that are measured in-flight. While implementing this function in the (ACS), the problem of checking the sufficiency of the used information for ensuring the required precision of the model arises. We must do this checking a priori (to determine a set of operation modes, the shape of the engine test impact and volume of recorded information) and a posteriori. Equations of the engine models are considered. Relations are derived that determine the precision of parameters of these models’ estimation depending on the precision of measurement, the composition of the engine power ratings, and durability of observations, at a stepwise change of fuel flow. We present these relations in non-dimensional coordinates that make them universal and ready for application to any turboshaft engine.

3

Design of experiments for the adjustment of fuzzy logic-based controls of an electrostatic separation process

Bouleriah Mohamed Elamine, Medles Karim, Dahou Omar

Przegląd Elektrotechniczny

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2022

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R. 98, nr 7

171--177

EN

The main objective of this paper is to design an intelligent control to improve the separator process of electrostatic rotating electrode separator by fuzzy logic. Where the methodology of designing experiments was used to form a knowledge base, and from it extract the important variables and the way they affect the outputs, as well as the interaction between them and established the mathematical model by using Minitab 18 software, while the MTLAB programs were used to simulate the fuzzy control system. The results showed the ability of the controller to improve the separation process in a good time, which will lead to saving time and energy.

PL

Głównym celem tego artykułu jest zaprojektowanie inteligentnego sterowania usprawniającego proces separatora elektrostatycznego separatora elektrody wirującej za pomocą logiki rozmytej. Tam, gdzie metodyka projektowania eksperymentów została wykorzystana do stworzenia bazy wiedzy, z której wyodrębniono ważne zmienne i sposób, w jaki wpływają one na wyniki, a także interakcje między nimi i ustalono model matematyczny za pomocą oprogramowania Minitab 18, natomiast MTLAB programy zostały wykorzystane do symulacji rozmytego systemu sterowania. Wyniki wykazały zdolność sterownika do usprawnienia procesu separacji w odpowiednim czasie, co przełoży się na oszczędność czasu i energii.

4

An approach to identify the interactions between the control factors in a Mahalanobis-Taguchi System

Labidi Amal, Tanabe Ikuo, Tanabe Yuko, Isobe Hiromi

Journal of Machine Engineering

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2022

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Vol. 22, No. 1

96--110

EN

The Mahalanobis-Taguchi System (MTS) is, today, widely used to define the optimal conditions for the design stage of product development especially, in the field of Artificial Intelligence (AI) considering the non-linear properties and non-digital data. In this paper, an approach to identify the several interactions in a MTS is proposed. The MTS contains four methods; Mahalanobis-Taguchi (MT) method, Mahalanobis Taguchi Adjoint (MTA) method, Recognition Taguchi (RT) method and Taguchi (T) method. The method to use for the analysis is selected based on the system’s properties. For the case of study used in this research, the unit space is created through the RT method and used to calculate the Mahalanobis-Taguchi distances (MTD). For the method proposed in this paper, the relationships between control factors and MTDs were firstly clarified by MTS (RT), then the same relationships were clarified using a modified design of experiments method, and the several interactions between control factors in MTS (RT) were finally identified by comparing the two relationships. Then effectiveness of the proposed method was evaluated by using a mathematical model.

5

Influence of Sawdust Ash Addition on Molding Sand Properties and Quality of Iron Castings

Khuengpukheiw R., Veerapadungphol S., Kunla V., Saikaew Charn

Archives of Foundry Engineering

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2022

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Vol. 22, iss. 4

53--64

EN

Sand molding casting has been widely used for a long time. But, one of its main drawbacks is that surface quality of the castings is not good enough for some applications. The purposes of this research were to investigate the effect of addition of sawdust ash of rubber wood (SARW) on molding sand properties and the surface quality of iron castings and to find an appropriate level of SARW with the appropriate properties of the iron castings. The molding sand compositions for making a sand mold consisted of the recycled molding sand, bentonite, water and SARW. The percentage levels of SARW were 0%, 0.1%, 0.2%, 0.3% and 0.4%. The different proportions of molding sand samples were investigated for the molding sand properties including permeability, compression strength and hardness. The results showed that addition of SARW had an effect on the molding sand properties. The appropriate percentage proportion of molding sand was obtained at 95.8% recycled molding sand, 0.8% bentonite, 3% water and 0.4% SARW. There were statistically significant differences of mean surface roughness and hardness values of the iron castings made from molding sand samples without SARW addition and the appropriate percentage proportion of molding sand. In addition, the average surface roughness value of the iron castings made from the sand mold with the appropriate percentage proportion of molding sand was ~40% lower than those of the iron castings made from molding sand samples without SARW addition.

6

Optymalizacja procesów jednostkowych w technologii organicznej

Balicki Sebastian

Przemysł Chemiczny

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2021

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T. 100, nr 5

490--497

PL

Wykorzystanie metod projektowania eksperymentów oraz optymalizacji operacji jednostkowych znajduje coraz większe zastosowanie w dziedzinie inżynierii chemicznej, z powodu coraz większego zapotrzebowania na tworzenie racjonalnych i zrównoważonych procesów technologicznych. Inżynier procesowy, dzięki nowoczesnym modelom obliczeniowym, może z powodzeniem zaimplementować planowanie eksperymentu już na wczesnym etapie prac z zakresu badań i rozwoju oraz optymalizacji całych procesów technologicznych, uzyskując założone cele w znacznie krótszym czasie. Przedstawiono zarys kryteriów postępowania przy planowaniu i optymalizacji procesów oraz opis powszechnie stosowanych modeli optymalizacyjnych wraz z ich porównaniem.

EN

The methods of designing expts. and optimization of unit operations were presented. The criteria that should be followed in the design and optimization of expts. and processes were discussed. Commonly used optimization models such as full factor design, fractional factor design, central composite design, optimal design, Taguchi design, Box-Behnken method and optimal planning models were described and compared.

7

Using metamodeling and fluid-structure interaction analysis in multi-objective optimization of a butterfly valve

Pałys Laura, Mrzygłód Mirosław W.

Computer Assisted Methods in Engineering and Science

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2021

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Vol. 28, no. 1

17--38

EN

Along with the increase in computing power, new possibilities for the use of parametriccoupled analysis of fluid flow machines and metamodeling for many branches of industryand medicine have appeared. In this paper, the use of a new methodology for multi-objective optimization of a butterfly valve with the application of the fluid-structure interaction metamodel is presented. The optimization objective functions were to increasethe value of the KV valve’s flow coefficient while reducing the disk mass. Moreover, theequivalent von Mises stress was accepted as an additional constraint. The centred composite designs were used to plan the measuring point. Full second-order polynomials, non-parametric regression, Kriging metamodeling techniques were implemented. The optimization process was carried out using the multi-objectives genetic algorithm. For eachmetamodel, one of the optimization candidates was selected to verify its results. The besteffect was obtained using the Kriging method. Optimization allowed to improve the KVvalue by 37.6%. The metamodeling process allows for the coupled analysis of the fluidflow machines in a shorter time, although its main application is geometry optimization.

8

Effect of hydrogen peroxide and lead(II) nitrate on gold cyanide leaching of Malaysian mesothermal deposit gold ore

Baharun Norlia, Ling Ong Pek, Ardani Mohammad Rezaei, Ariffin Kamar Shah

Physicochemical Problems of Mineral Processing

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2020

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Vol. 56, iss. 5

905--918

EN

The gold extraction from Malaysian mesothermal lode gold ore through the cyanidation method was performed. The effect of hydrogen peroxide (H2O2) and lead nitrate Pb(NO3)2 were investigated on the percentage of gold recovery. The statistical analysis method using a response surface design-central composite design was applied to find the optimum condition for gold extraction. The studied parameters were NaCN concentration (300-500 ppm), H2O2 concentration (205-410 ppm), and Pb(NO3)2 concentration (50-150 ppm). It was found that increasing the amount of NaCN and H2O2 as well as decreasing the amount of Pb(NO3)2 in the studied range, increased the gold recovery. The analysis of variance suggested the linear model for the gold extraction with the optimum condition at 467.3 ppm NaCN, 94.96 ppm Pb(NO3)2, and 340 ppm H2O2. The gold extracted from the ore at the optimum condition was 88.97% as compared to 62.02% from conventional cyanidation. The characterization study of the gold ore indicated that the finely gold particles interlocked in the aluminosilicate phase (grain size of ~10.0 μm). The Van’t Hoff differential method justified that the cyanidation was of second order with a specific reaction rate of 0.0501/hour.

9

Praktyczne aspekty niskotemperaturowego utleniania materiałów ogniotrwałych typu MgO–C

Zelik Wiesław, Lech Ryszard

Materiały Ceramiczne

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2020

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T. 72, nr 2

77--90

PL

Niskotemperaturowe utlenianie wyrobów ogniotrwałych MgO-C jest jednym z czynników wpływających na czas pracy kadzi głównej stalowniczej. Utlenianie ma miejsce podczas eksploatacji urządzenia w temperaturach poniżej 1200 °C w okresach gotowości urządzenia do pracy. W tym czasie utrzymuje się wymaganą temperaturę wyłożenia roboczego, a mieszanina gazów zawierająca tlen, wypełniająca wnętrze kadzi, oddziałuje korozyjnie na część węglową materiałów ogniotrwałych. Badania odwęglania przeprowadzono na formowanych mechanicznie kształtkach z wybranego materiału magnezjowo-węglowego o składzie typowym dla zastosowań w strefach żużla kadzi głównych. Odporność materiału na niskotemperaturowe utlenianie badano w piecu oporowym w zależności od czasu utleniania, temperatury utleniania oraz ciśnienia formowania, od którego zależy porowatość otwarta materiału kształtek. W badaniach użyto dwóch grafitów płatkowych różniących się uziarnieniem i czystością. Badania przeprowadzono według trójpoziomowego planu całkowitego typu 3S, umożliwiającego statystyczną analizę nieliniowej charakterystyki zastępczej odporności materiału na niskotemperaturowe utlenianie. Uzyskane wyniki pozwalają na ocenę wpływu temperatury utleniania, czasu utleniania i porowatości otwartej wykorzystanych materiałów na utlenianie nisko-temperaturowe. Wyniki pracy są praktyczną wskazówką dla użytkowników kadzi głównych.

EN

Low-temperature oxidation of MgO-C refractory materials is one of the factors influencing the length of service of a steel ladle. Oxidation occurs during the ladle’s operation at temperatures below 1200 °C, in the periods when it is kept on standby. At this time, the required temperature of the working lining is maintained, and the mixture of oxygen-containing gases inside the ladle has a corrosive effect on the carbon part of the refractory materials. Investigations of decarburization were conducted on mechanically formed shapes made of a selected magnesia-carbon material with a composition typical for applications in ladle slag zones. The material’s resistance to low-temperature oxidation was tested in resistance furnaces versus time, temperature, and moulding pressure, which determines the open porosity of the shapes’ material. In the investigations, two flake graphites, differing in grain size distribution and cleanness, were used. The tests were carried out according to a three-level full factorial design type 3S, which enables conducting a statistical analysis of the nonlinear substitute characteristics of the material’s resistance to low-temperature oxidation. The obtained results allow evaluating the effect of temperature, time, and open porosity on the process of material’s low-temperature oxidation. The results of work can provide a practical indication for steel ladle users.

10

The analysis of EDM electrodes wear in corners and edges

Mouralova K., Bednar J., Benes L., Hrabec P., Kalivoda M., Fries J.

Archives of Civil and Mechanical Engineering

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2020

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Vol. 20, no. 4

484--497

EN

Die-sinking electrical discharge machining is an unconventional technology that allows to machine all at least minimally electrically conductive materials regardless of their physical and mechanical properties. Despite the fact that it is not a conventional technology, the tool gets also worn out, which is a tool electrode. The wear of the electrode does not only mean its loss but also the degradation of the shapes that are transferred to the resulting workpiece. For this reason, a design of experiments was conducted with 6 input factors, 2 were categorical: the electrode material (copper, graphite) and workpiece material (steel 1.2363 and steel 1.2343ESR) and 4 were numerical: Open-voltage, Pulse current, Pulse on-time, and Pulse off-time. In the framework of this design of experiments, the wear of the used graphite and copper electrodes at their corners and edges was evaluated, which was made possible by the use of electron microscopy and the use of approximation circles. Furthermore, the eroding speed, the topography of the machined samples, and the morphology of the surfaces of the used electrodes were investigated. It has been recognized that the use of a graphite electrode will allow for more accurate workpiece shapes and less wear.

11

Prediction of the optimum tensile – shear strength through the experimental results of similar and dissimilar spot welding joints

Mahmood Najmuldeen Yousif

Archive of Mechanical Engineering

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2020

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LXVII, nr 2

197--210

EN

Resistance spot welding is the most significant joining technique utilized in various industries, like automotive, boilers, vessels, etc., that are commonly subjected to variable tensile-shear forces due to the unsuitable use of the input spot welding variables, which mainly cause the welded joints failure during the service life of the welded assembly. So, in order to avoid such failures, the welding quality of some materials like aluminum must be improved taking into consideration the performance and weight saving of the welded structure. Thus, the need for optimizing the used welding parameters becomes essential for predicting a good welded joint. Accordingly, this study aims at investigating the influence of the spot welding variables, including the squeeze time, welding time, and current on the tensile-shear force of the similar and dissimilar lap joints for aluminum and steel sheets. It was concluded that the use of Taguchi design can improve the welded joints strength through designing the experiments according to the used levels of the input parameters in order to obtain their optimal values that give the optimum tensile-shear force as the response. As a consequence of the present work, the optimal spot welding parameters were successfully obtained.

12

Approximating curve by a single segment of B-Spline or Bézier curve directly in CAD environment

Sobolak Mariusz, Połowniak Piotr, Marciniec Adam, Jagiełowicz Patrycja Ewa

Advances in Manufacturing Science and Technology

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2020

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Vol. 44, nr 3

84--92

EN

The paper presents the method of approximating curves with a single segment of the B-Spline and Bézier curves. The method for determining a single curve segment using the optimization methods in the CATIA environment is shown. The algorithms of simulated annealing and design of experiment are used for optimization. For the same purpose, a new original procedure for determining the distance between the given curves using explicit parameters in the CATIA environment was also used. This approximation of the cyclic curves results in the curve oscillation as shown in the examples. The results show that the approximation method with Bézier curve using control points as “free” points can be applied to obtain the best results of approximation.

13

A statistical approach to simulate instances of archeological findings fragments

Renno Fabrizio, Lanzotti Antonio, Papa Stefano

Journal of Automation Mobile Robotics and Intelligent Systems

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2019

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Vol. 13, No. 1

46--64

EN

First aim of this paper is to describe a methodology developed to create virtual fragments of archeological archetypes in CAD (Computer Aided Design) environment. A simple Reverse Engineering (RE) technique was adopted to reconstruct the shape of vases allowing the archeologists, and so the CAD inexpert personnel, to use it. Moreover, another relevant aspect is the definition of a procedure to simulate shape errors on the virtual prototypes to make more realistic the results. The characteristics of the fragments to be reproduced were selected by means of Design of Experiment (DOE) techniques. So, an algorithm was implemented to simulate the shape error, related to the working operations, that represents the typical noise for the feature recognition of archeological findings. Furthermore, this algorithm can make more complex the hypotheses related to the Gaussian model of simulation of the error and can adapt the value of the shape error (i.e. increasing it) according to the data gathered in archaeological excavation. The case study was based on the definition of a catalogue of archetypes of the black Campanian vases studied and classified by the archeologist J.P. Morel. The procedure conceived was applied to five (among one hundred) vases of the virtual catalogue obtaining forty instances of fragments affected by errors and so creating virtual mock-ups of typical pieces which may be found in the archeological site considered for the case study.

14

The study of novel light stabilizer enhance UV filtering in waterborne UV-curable coatings

Yung-Chi Yang, Yin-Ting Lai, Yu-Shu Sung, Chung-Han Lu, Miles Hsieh, Yao-Hsing Huang

Farby i Lakiery

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2019

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nr 2

22--29

EN

Waterborne Ultra Violet (UV-curable coatings) have been developed to replace conventional UV-curable coatings with higher VOC content. Due to fast-drying and short processing time UV-curable coating are widely used in various industries. However, there are 2 major challenges: the first one is discoloration after long-term exposure to sunlight; the other is to keep the ability of UV filtering ability since waterborne UV-curable coatings are usually applied to the surface as a protection top coat. The novel light stabilizer (NLS) is developed specifically for waterborne UV-curable coatings. Design of Experiment (DOE) was used in the study. Test data showed that the designed NLS would not interfere the curing speed of the tested clear waterborne UV-curable coating system. Moreover, the results confirmed that by increasing the concentration of NLS could enhance the UV filtering ability and weatherability of the tested clear top coat more effectively than by increasing the coating thickness: at 365nm wavelength, the effect factor of NLS is 62.5%, while DFT (dry film thickness) is 20.9%; at 380nm, the effect factor of NLS is 47.7%, while DFT is only 27.4%. For NLS, the effect of reducing yellowing is 76.8%. For film thickness, the effect is only 7.7%.Our test results confirmed the designed NLS could block the UV light without compromising the UV-curing speed, and is suitable for enhancing the weatherability and protection ability of the clear waterborne UV-curable coatings.

PL

Powłoki wodorozcieńczalne utwardzane UV zostały opracowane w celu zastąpienia konwencjonalnych powłok utwardzalnych promieniowaniem UV o większej zawartości LZO. Dzięki szybkiemu schnięciu i krótkiemu czasowi obróbki, powłoki utwardzane promieniowaniem UV są szeroko stosowane w różnych gałęziach przemysłu. Istnieją jednak dwa główne wyzwania: pierwszy to przebarwienia po długotrwałej ekspozycji na światło słoneczne; drugim jest utrzymanie zdolności filtrowania UV, ponieważ wodorozcieńczalne powłoki UV są zwykle nakładane na powierzchnię jako wierzchnia warstwa ochronna. Nowy stabilizator światła (NLS) został opracowany specjalnie do zastosowania w wodorozcieńczalnych wyrobach utwardzanych promieniowaniem UV. W badaniu wykorzystano projektowanie eksperymentu. Wyniki badań wykazały, że zaprojektowany NLS nie zakłóca szybkości utwardzania testowanego transparentnego, wodorozcieńczalnego systemu powłokowego UV. Ponadto wyniki potwierdziły, że poprzez zwiększenie stężenia NLS możliwe jest zwiększenie zdolności filtrowania UV i odporności na warunki atmosferyczne badanej powłoki skuteczniej niż przez zwiększenie grubości powłoki: przy długości fali 365 nm, współczynnik efektu NLS wynosi 62.5%, podczas gdy DFT (grubość suchej powłoki) wynosi 20.9%; przy 380 nm współczynnik efektu NLS wynosi 47.7%, podczas gdy DFT wynosi tylko 27.4%. W przypadku NLS efekt zmniejszenia żółknięcia wynosi 76.8%. Wyniki badań potwierdziły, że opracowane NLS mogą blokować światło UV bez pogarszania szybkości utwardzania UV i są odpowiednie do zwiększenia odporności na warunki atmosferyczne i zdolności do ochrony transparentnych, wodorozcieńczalnych powłok utwardzanych promieniowaniem UV.

15

Parametric analysis of the sensitivity of a prestressed concrete beam using the DOE simulation technique

Woliński Sz., Pytlowany T.

Archives of Civil Engineering

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2019

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Vol. 65, nr 4

97--112

EN

The paper presents the method of simplified parametric analysis of the sensitivity of a pre-tensioned concrete beam. The presented approach is based on the DOE (design of experiments) data collection which is simulation technique allowing for identification of variables deciding about the effectiveness and costs of designed structures. Additionally, application of the hyper-surface of the construction response allows designers to the development of multi-dimensional trade-off graphs to facilitate, the assessment of the scope of changes in random state variables permitted due to the adequate criteria and selection of their values close to optimum. Design basics, procedures and results of the presented considerations of sensitivity assessment and reliability of the structure has been shown on the example of a pre-stressed concrete beam designed in accordance with the requirements and procedures of Eurocode 2.

PL

W artykule przedstawiono metodę analizy wpływu zmiennych wejściowych na parametry charakteryzujące stan konstrukcji sprężonych w początkowej i trwałej sytuacji obliczeniowej, opartą na symulacjach komputerowych i technice zbierania informacji DOE (Design Of Experiments). Założenia, procedury i wyniki zastosowania techniki DOE przedstawiono na przykładzie belki strunobetonowej zaprojektowanej zgodnie z wymaganiami Eurokodu 2. Przeprowadzono analizę typu „what-if” wpływu wartości obciążenia i siły sprężającej w poszczególnych cięgnach (uwzględniając straty wynikające z relaksacji stali sprężającej) oraz modułu sprężystości podłużnej betonu na nośność graniczną i maksymalne ugięcie belki.

16

The Response Surface Methodology revisited – comparison of analytical and non-parametric approaches

Osocha P.

Production Engineering Archives

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2018

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Vol. 20

49--53

EN

Since G.E.P. Box introduced central composite designs in early fifties of 20th century, the classic design of experiments (DoE) utilizes response surface models (RSM), however usually limited to the simple form of low-degree polynomials. In the case of small size datasets, the conformity with the normal distribution has very weak reliability and it leads to very uncertain assessment of a parameter statistical significance. The bootstrap approach appears to be better solution than – theoretically proved but only asymptotically equal – t distribution based evaluation. The authors presents the comparison of the RSM model evaluated by a classic method and bootstrap approach.

17

The outline of the expert system for the design of experiment

Dwornicka R., Pietraszek J.

Production Engineering Archives

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2018

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Vol. 20

43--48

EN

The design of experiment (DoE) is a methodology originated from early 1920s when Fisher’s papers created the analysis of variance and first known experimental designs: latin squares. It is focused on a construction of empirical models based on measurements obtained from specifically structured and driven experiments. Its development resulted in the constitution of four distinctive branches recognized by the industry: factorials (full or fractional), Taguchi’s robust design, Shainin’s Red-X® and a response surface methodology (RSM). On one hand, the well-known success stories of this methodology implementations promise great benefits, while on other hand, the mathematical complexity of mathematical and statistical assumptions very often lead to improper use and wrong inferences. The possible solution to avoid such mistakes is the expert system supporting the design of experiments and subsequently the analysis of obtained data. The authors propose the outline of such system and provides the general analysis of the ontology and related inference rules.

18

Evaluation of outsourcing transportation contract using simulation and design of experiment

Setamanit S.

Polish Journal of Management Studies

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2018

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Vol. 18, No. 2

300--310

EN

This paper aims to develop an approach to identify optimal fleet size under uncertainty and to identify important factors affecting transportation performance. The methodologies used in this paper are two folded. The first methodology is to develop a simulation model that allows manager to evaluate the impact of having different number of trailers on delivery and cost in order to identify the optimal fleet size. The second methodology is to use a Design of experiment (DOE) together with the simulation model to identify important factors that affect transportation performances. The result shows that the company should hire 16 trailers, which will reduce the delivery delay from 14% to 0.02%. Furthermore, it is found that variation in demand has a strong impact on late delivery and cost. There is also an interaction between demand variation and transportation time variation.

PL

Niniejszy dokument ma na celu opracowanie podejścia do określania optymalnej wielkości floty w warunkach niepewności oraz określenie ważnych czynników wpływających na wydajność transportu. Metodologie stosowane w tym artykule są złożone. Pierwszą metodologią jest opracowanie modelu symulacyjnego, który umożliwi menedżerowi ocenę wpływu posiadania różnych przyczep i kosztów w celu określenia optymalnego rozmiaru floty. Drugą metodologią jest wykorzystanie projektu eksperymentu (DOE) wraz z modelem symulacyjnym w celu zidentyfikowania ważnych czynników wpływających na wydajność transportu. Wynik pokazuje, że firma powinna wynająć 16 przyczep, co zmniejszy opóźnienie dostawy z 14% do 0.02%. Ponadto stwierdzono, że zróżnicowanie popytu ma duży wpływ na opóźnienia w dostawie i koszty. Istnieje również interakcja między zmiennością popytu a zmiennością czasu transportu.

19

Identyfikacja modelu konstrukcji wsporczej linii napowietrznej z zastosowaniem techniki planowania eksperymentu

Szopa K.

Modelowanie Inżynierskie

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2018

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T. 36, nr 67

67--74

PL

W artykule przedstawiono proces identyfikacji numerycznego modelu konstrukcji prętowej o złożonej geometrii i wielu stopniach swobody, na podstawie dynamicznej odpowiedzi obiektu. Przedmiotem badań jest uproszczony model fizyczny kratowego słupa linii napowietrznej, dla którego przeprowadzono eksperymentalną analizę modalną, wyznaczając parametry modalne dla sześciu postaci drgań własnych w 72 stopniach swobody. Z wykorzystaniem techniki planowania eksperymentu wyznaczono powierzchnie odpowiedzi, przeprowadzono optymalizację i dokonano estymacji poszukiwanych parametrów modelu numerycznego. Na koniec zweryfikowano zidentyfikowany model numeryczny, porównując jego własności dynamiczne z modelem eksperymentalnym.

EN

The article presents the process of identifying a numerical model of a rod structure with complex geometry and multiple degrees of freedom, on the basis of dynamic response of the object. The subject of the research is a simplified physical model of a lattice supporting structure of overhead power line for which experimental modal analysis was carried out, determining modal parameters for 6 modes at 72 degrees of freedom. Using the design of experiment technique response surfaces were determined, the optimization was conducted and the parameters of the numerical model were estimated. Finally, the identified numerical model was verified by comparing its dynamic properties with the experimental model.

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Planning experiment for laboratory tests on rock abrasivity

Mucha K., Krauze K.

Mining – Informatics, Automation and Electrical Engineering

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2018

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R. 56, nr 3

17--24

EN

The physical and mechanical properties of rocks (i.e., compressive strength, tensile strength, workability, or compactness) are often taken into account during the selection of a mining method and type of mining machine as well as the mining tools themselves. However, one of the main reasons for the abrasive wear of mining picks is the abrasiveness of rocks, which is seldom taken into consideration because there is lack of unambiguous and proven methods for its determination. The article presents the research plan and methodology, the stand for testing the abrasivity of rocks, the course of conducting preliminary tests as well as the statistical treatment of the results using the Statistica program, and determining the final values of the input variables in the basic research. The method has been developed taking into account rock abrasivity when selecting and forecasting the wear of mining tools.