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1

The effect of selected wedm parameters on cut surface quality of 2017A aluminum

Jamróz Konrad, Gałda Lidia

Technologia i Automatyzacja Montażu

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2024

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nr 1

3--9

EN

With the wire electrical discharge machining (WEDM), good quality machined surfaces can be achieved. The WEDM is worth considering for machining fasteners used in assembly processes. This paper presents a study of the WEDM cutting process of aluminum 2017A using an WEDM machine of the FR 400 type. After applying different cutting speeds, the characteristics of the cut surface were evaluated. Despite some differences in the shape of surface profiles and surface morphology noted after WEDM cutting at different speeds, the analysis of variance concluded that the WEDM cutting speed in the studied variation range of 23-125 μm/s has no significant effect on surface roughness. At the highest speed studied, machining efficiency can be increased, affecting cost and energy reduction, while maintaining an acceptable and comparable level of surface quality after WEDM cutting.

PL

Dzięki obróbce elektroerozyjnej można uzyskać dobrą jakość obrabianych powierzchni. Warto rozważyć zastosowanie obróbki elektroerozyjnej do obróbki elementów złącznych wykorzystywanych w procesach montażowych. W artykule przedstawiono badania procesu cięcia elektroerozyjnego aluminium 2017A z zastosowaniem elektrodrążarki typ FR 400. Po zastosowaniu zróżnicowanej prędkości obróbki poddano ocenie stan powierzchni cięcia. Pomimo zauważonych pewnych różnic w kształcie profili powierzchni i morfologii powierzchni po cięciu elektroerozyjnym z różnymi prędkościami, to w wyniku analizy wariancji stwierdzono, że prędkość cięcia poprzez elektrodrążenie w badanym zakresie zmienności 23-125 μm/s nie wywiera istotnego wpływu na chropowatość powierzchni. Przy największej badanej prędkości można zwiększyć wydajność obróbki, wpływając na zmniejszenie kosztów i energii, zachowując akceptowalny i porównywalny poziom jakości powierzchni po cięciu elektroerozyjnym.

2

Workload control in flow shops with bottleneck shifting and process time variability

Prabhu Aruna, Raghunandana K, Yogesh Pai P

Production Engineering Archives

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2024

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Vol. 30, Iss. 1

48--56

EN

Manufacturing industries struggle to devise precise planning and scheduling solutions due to unpredictable business situations. Additionally, uncertainties in production such as machine breakdowns, labour absenteeism, cycle time deviations, etc., would further deteriorate production plans and lead to uncertainty in decision-making processes. Flow shops with bottlenecks are particularly susceptible to these disturbances. Moreover, the random variations in cycle time variations can cause the bottleneck to shift between different stages. Literature indicates that conventional job release methods are ineffective in addressing these difficulties. In contrast, workload control methods would provide better solutions. Hence, a flow shop model has been developed and simulated using the variables like process time variations and bottleneck shifting on the discrete-event simulation software. The flow shop model incorporates realistic shop characteristics which are subjected to random process time variations, so as to assess the performance. The outcomes of the experimentation demonstrate that order release methods play a pivotal role in improving the performance of flow shops in more volatile situations.

3

Experimental investigation and machining analysis of Mg/TiC composites during EDM

Dash Dharmeswar, Devarajaiah Devarasiddappa, Dash Santosh Kumar, Samanta Sutanu, Rai Ram Naresh

Composites Theory and Practice

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2024

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R. 24, nr 1

9--16

EN

Electrical discharge machining (EDM) is one of the prominent non-conventional machining processes used to machine metal matrix composites. Mg/TiC composites are found in many industrial applications and conventional machining of the same is highly challenging. This paper aims to study the machinability analysis of Mg/TiC composites using EDM with pulseon time (Ton), pulse-off time (Toff) and input current (I) as the process variables with the material removal rate (MRR) and surface roughness (SR) as the performance measures. Stir cast Mg-alloy reinforced with TiC (0, 5, 10, 15 and 20) by weight was used as the workpiece. The EDM experiments were conducted as per L25 orthogonal array (OA) and the results were analyzed to study the effect of the process variables on MRR and SR. The parametric study showed that SR increases linearly with Ton and is attributed to larger craters produced at a higher pulse energy. MRR was also observed to grows with the rise in Ton as more material melts due to high-intensity pulses. As per the ANOVA results, Ton was found to be the most influential process variable affecting SR and MRR with a 79% and 34% contribution, respectively. Surface morphology investigations using SEM micrographs revealed the presence of globules and sphere-shaped metal deposits and were found responsible for increased SR.

4

Effect of floating-plug drawing process parameters on surface finish of inner and outer surfaces of AISI 321 stainless steel thin-walled tubes

Żaba Krzysztof, Szpunar Marcin

Advances in Mechanical and Materials Engineering

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2024

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Vol. 41, nr 1

27-37

EN

This article presents the results of the analysis of changes in the surface topography of AISI 321 (1.4541) thin-walled stainless steel tubes in single-pass Floating-Plug Drawing (FPD) process. Experimental tests were carried out with variable drawing speed (1, 2, 3, 4, 6, and 10 m/min) and different angles of floating plug (11.3°, 13° and 14°). Wisura DSO7010 (Fuchs Oil) lubricant was used in the experiments. Mean roughness Ra and ten point height of irregularities Rz were adopted as surface quality indicators. Roughness parameters were measured independently on the inner and outer surfaces of thin-walled tubes. Analysis of variance was used to analyse the relationship between process parameters (drawing speed and angle of floating plug) and surface roughness of tubes. A decrease in the values of both analyzed roughness parameters was observed as a result of the drawing process. The FPD process significantly improves the inner surface quality of AISI 321 thin-walled stainless steel tubes. The mean roughness value tends to increase with increasing drawing speed, while the angle of the floating-plug has no significant effect on the mean roughness Ra.

PL

W artykule przedstawiono wyniki analizy zmian topografii powierzchni rur cienkościennych ze stali nierdzewnej AISI 321 po procesie ciągnienia na korku swobodnym. Badania eksperymentalne przeprowadzono w jednym przejściu, ze zmienną prędkością ciągnienia (1, 2, 3, 4, 6, and 10 m/min) oraz różnymi kątami β korka swobodnego (11.3°, 13° and 14°). W badaniach eksperymentalnych wykorzystano smar Wisura DSO7010 (Fuchs Oil). Jako wskaźniki jakości powierzchni przyjęto średnie arytmetyczne odchylenie rzędnych profilu Ra oraz wysokość chropowatości według 10 punktów Rz. Parametry chropowatości mierzono niezależnie na wewnętrznej i zewnętrznej powierzchni rur cienkościennych. Do analizy związków pomiędzy parametrami procesu ciągnienia (prędkość ciągnienia i kąt korka swobodnego) wykorzystano analizę wariancji. Zaobserwowano zmniejszenie wartości obydwu analizowanych parametrów chropowatości w wyniku procesu ciągnienia. Proces ciągnienia na korku swobodnym znacznie poprawia jakość wewnętrznej powierzchni cienkościennych rur ze stali nierdzewnej AISI 321. Zaobserwowano tendencję do zwiększania się parametru Ra wraz ze wzrostem prędkości ciągnienia, podczas gdy kąt β korka swobodnego nie miał znaczącego wpływu na średnią chropowatość Ra.

5

A survey of applications of the Kruskal Wallis test in wind power generation

Mbuli Nhlanhla, Diya Mthobisi

Przegląd Elektrotechniczny

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2023

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R. 99, nr 4

140--144

EN

The authors present the results of a survey on the use of the Kruskal Wallis test in wind power generation research. An overall assessment of the qualifying publications suggested that they could be categorized into 4 logical application areas. The time series of the annual number of publications indicated a steady trend in the numbers produced annually and most publications were in the category of environmental issues. The survey contributes to the body of knowledge on wind power generation and also creates a depository of references in one source.

PL

e. Autorzy przedstawiają wyniki ankiety dotyczącej wykorzystania testu Kruskala Wallisa w badaniach energetyki wiatrowej. Ogólna ocena kwalifikujących się publikacji sugeruje, że można je podzielić na 4 logiczne obszary zastosowań. Szeregi czasowe rocznej liczby publikacji wskazywały na stały trend w liczbach wydawanych rocznie, a większość publikacji dotyczyła kwestii środowiskowych. Ankieta wzbogaca wiedzę o energetyce wiatrowej, a także tworzy depozyt referencji w jednym źródle.

6

Assessment of the tribological performance of bio-based lubricants using analysis of variance

Szewczyk Marek, Szwajka Krzysztof

Advances in Mechanical and Materials Engineering

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2023

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Vol. 40, nr 1

31--38

EN

The purpose of this article is to determine the coefficient of friction of a DC04 steel sheet using a specially designed flat-die strip drawing test. Four different bio-based lubricants, edible (sunflower and rape-seed) and non-edible (karanja and moringa) were used in the study. The experiments were carried out for different contact pressure values. The as-received specimens were pre-strained with strains of 7, 14, and 21%. The values of the coefficient of friction as a ratio of the friction force to the normal force were determined. The influence of the viscosity of the lubricant and the contact pressure on the value of the coefficient of friction has been investigated using ANOVA. A tendency to a decrease in the coefficient of friction with increasing contact pressure was observed. Significance results obtained after the ANOVA analysis confirmed the influence of normal pressure and oil viscosity on the value of the coefficient of friction. At the same time, the hypothesis about the influence of the sheet pre-straining on the value of the coefficient of friction was not confirmed by the significant interactions.

PL

Celem artykułu jest wyznaczenie współczynnika tarcia blachy stalowej DC04 za pomocą specjalnego przyrządu do realizacji testu przeciągania pasa blachy. W badaniach wykorzystano cztery różne smary pochodzenia naturalnego: jadalne (oleje słonecznikowy i rzepakowy) oraz niejadalne (karanja i moringa). Eksperymenty przeprowadzono dla różnych wartości nacisku. Próbki w postaci pasów blachy wstępnie odkształcono do wartości 7, 14 i 21%. Wartości współczynnika tarcia wyznaczono jako stosunek siły tarcia do siły normalnej. Wpływ lepkości środka smarnego i nacisku kontaktowego na wartość współczynnika tarcia określono za pomocą analizy ANOVA. Zaobserwowano tendencję do zmniejszania się współczynnika tarcia wraz ze wzrostem nacisku. Wyniki istotności otrzymane po przeprowadzonej analizie ANOVA, potwierdziły zależność współczynnika tarcia od nacisku normalnego i lepkości oleju, jednocześnie zaprzeczając hipotezę o wpływie odkształcenia wstępnego na wartość współczynnika tarcia oraz możliwość wystąpienia istotnych interakcji.

7

Influence of the production direction of European Union farms on the level of financial liabilities

Firlej Krzysztof, Kubala Sebastian

Zeszyty Naukowe. Organizacja i Zarządzanie / Politechnika Śląska

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2022

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z. 158

163--173

EN

Purpose: The main purpose of the study was to investigate the relationship between the direction of production of farms in the European Union and the level of their liabilities. Design/methodology/approach: The study period includes the years 2005-2019. Data relating to eight types of farming identified in the FADN database were used to illustrate the directions of production. The conducted research focuses on the following types of liabilities: total, incurred for a period longer than one year and incurred for a period of less than one year with outstanding cash payments. One-way ANOVA variance was used to achieve the research objective. Findings: The conducted research showed that the most common differences in the level of liabilities are between the type of granivores and the types of farms focused on plant production and other permanent crops with farms focused on field crops, horticulture and livestock production. Relatively few differences can be observed in the case of farms targeting the same source of food origin (except for other permanent crops). Originality/value: The obtained results indicate a significant differentiation in the level of liabilities in farms focused on plant and livestock production, which results from the different specificity of their production.

8

Catalytic Debenzylation of 2,4,6,8,10,12-Hexabenzyl-2,4,6,8,10,12-hexaazatetracyclo [5.5.0.0.3,1105,9] Dodecane with Pd(OH)2/Al2O)3 in a Batch Suspension Reactor and Optimization of the Reaction Parameters via the Taguchi Method

Bayat Yadollah, Azizkhani Vahid

Central European Journal of Energetic Materials

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2022

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Vol. 19, no. 3

231--247

EN

In this paper, the Taguchi method was used for the optimization of the reaction parameters for the synthesis of 2,6,8,12-tetraacetyl-4,10-dibenzyl-2,4,6,8,10,12-hexaazatetracyclo[5,5,0,03,11,05,9]dodecane in the presence of Pd(OH)2/Al2O)3 catalyst in a batch suspension reactor. In order to achieve optimal conditions for this reaction, the experimental studies were conducted under varying reaction parameters, such as temperature, pressure, catalyst to substrate weight ratio, reaction time, and co-catalyst amount. The setting of the reaction parameters was determined in Qualitek-4 (Nutek®) software using the Taguchi experimental design method. Identification of the significant factors and their attributed levels in the Taguchi method were statistically performed via the analysis of variance (ANOVA) technique.

9

The impact of the direction of production of the European Union agricultural enterprises at the level of total farming overheads

Kubala Sebastian

Zeszyty Naukowe. Organizacja i Zarządzanie / Politechnika Śląska

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2021

|

z. 151

299--310

EN

Purpose: The main aim of the study is to analyse the relationship between the production direction of the European Union agricultural enterprises and the different types of total farming overheads incurred by these agricultural enterprises. Additionally, the achieved results are to present how the direction of production of the European Union agricultural enterprises influences on the incurred total farming overheads relating to the functioning of the agricultural enterprises. Design/methodology/approach: The one-way analysis of variance ANOVA was used to realise the aim of the study. To present the production directions the data relating to the eight agricultural types listed in the FADN base were used. The conducted studies have been focused on the four types of total farming overheads relating to the performed production activities. The study covers all European Union member countries from the period from 2005 to 2017. Findings: The most frequent differences in bearing the different types of total farming overheads are evident between the type of horticulture, wine and permanent crops and the types of agricultural enterprises focused on livestock production. The several differences may be observed in case of the agricultural enterprises oriented on the same food sources Originality/value: There are significant differences in the level of the incurred total farming overheads between the agricultural enterprises oriented on crop production and livestock production. The much higher costs may be observed in the agricultural enterprises oriented on crop production, in particular in case of horticulture, wine and permanent crops.

10

Impact of logistics information systems on supply chain optimization: Case of Group Bachir Rachid

Belkacem Bouzida Ismahane, Merzoug Slimane

Journal of Sustainable Development of Transport and Logistics

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2021

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Vol. 6, No. 2

60--80

EN

Purpose: This paper aims to check the contribution of Logistics Information Systems - LIS to supply chain optimization in the steel industry group of Bachir Rachid. This group that owns eight independent companies and numerous points of sale and warehouses, has to be connected by such advanced systems to ensure effectiveness and profitability. Methodology: A questionnaire was distributed among a group of employees, and the collected data was later analyzed by SPSS 25 and complemented by further structured and unstructured interviews. We have realized an analysis of variance to evaluate the impact of LIS on logistics activities, supply chain management, and integration as well as optimization. The test of Kruskal-Wallis H was chosen due to the non-linearity of the data. Results: This work proves that Logistics Information Systems contribute to the performance of logistics activities, supply chain integration, and supply chain optimization through the enhancement of the efficiency of supply chain management and by the reduction of supply chain costs. The theoretical contribution: The contribution made to the theory of logistics and supply chain management lies in confirming previous findings on the contribution of LIS to logistics and supply chain optimization in Algeria, and more specifically, in the steel industry.

11

Design of a Taguchi-GRA optimized PID and adaptive PID controllers for speed control of DC motor

George Mary Ann, Kamat Dattaguru V.

Archives of Electrical Engineering

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2021

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Vol. 70, nr 4

759--775

EN

DC motors have wide acceptance in industries due to their high efficiency, low costs, and flexibility. The paper presents the unique design concept of a multi-objective optimized proportional-integral-derivative (PID) controller and Model Reference Adaptive Control (MRAC) based controllers for effective speed control of the DC motor system. The study aims to optimize PID parameters for speed control of a DC motor, emphasizing minimizing both settling time (Ts )and % overshoot (% OS) of the closed-loop response. The PID controller is designed using the Ziegler Nichols (ZN) method primarily subjected to Taguchi-grey relational analysis to handle multiple quality characteristics. Here, the Taguchi L9 orthogonal array is defined to find the process parameters that affect Ts and % OS. The analysis of variance shows that the most significant factor affecting Ts and % OS is the derivative gain term. The result also demonstrates that the proposed Taguchi- GRA optimized controller reduces Ts and % OS drastically compared to the ZN-tuned PID controller. This study also uses MRAC schemes using the MIT rule, Lyapunov rule, and a modified MIT rule. The DC motor speed tracking performance is analyzed by varying the adaptation gain and reference signal amplitude. The results also revealed that the proposed MRAC schemes provide desired closed-loop performance in real-time in the presence of disturbance and varying plant parameters. The study provides additional insights into using a modified MIT rule and the Lyapunov rule in protecting the response from signal amplitude dependence and the assurance of a stable adaptive controller, respectively.

12

Hybrid GRA-PCA and modified weighted TOPSIS coupled with Taguchi for multi-response process parameter optimization in turning AISI 1040 steel

Mst. Nazma Sultana, Nikhil Ranjan Dhar

Archive of Mechanical Engineering

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2021

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LXVIII, nr 1

23--49

EN

The objective of the present study is to optimize multiple process parameters in turning for achieving minimum chip-tool interface temperature, surface roughness and specific cutting energy by using numerical models. The proposed optimization models are offline conventional methods, namely hybrid Taguchi-GRA-PCA and Taguchi integrated modified weighted TOPSIS. For evaluating the effects of input process parameters both models use ANOVA as a supplementary tool. Moreover, simple linear regression analysis has been performed for establishing mathematical relationship between input factors and responses. A total of eighteen experiments have been conducted in dry and cryogenic cooling conditions based on Taguchi L18 orthogonal array. The optimization results achieved by hybrid Taguchi-GRA-PCA and modified weighted TOPSIS manifest that turning at a cutting speed of 144 m/min and a feed rate of 0.16 mm/rev in cryogenic cooling condition optimizes the multi-responses concurrently. The prediction accuracy of the modified weighted TOPSIS method is found better than hybrid Taguchi-GRA-PCA using regression analysis.

13

A Statistical Analysis of Evaporative Pattern Casting Process Parameters for the Production of Aluminum Alloy Components

Omidiji Babatunde Victor

Journal of Casting & Materials Engineering

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2020

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Vol. 4, no. 3

41--47

EN

Four process parameters were investigated with the aim of determining their influence on the mechanical properties of some test castings, bars, cylinders and plates. The influence was quantified in terms of percentage contribution. Analysis of variance (ANOVA), regression, main effects and interaction effects plots were employed to carry out the statistical analysis. As regards the tensile strength of the test castings, the geometry of components (GOC) dominated, contributing 90.83% and the pouring temperature (PT) contributed 91.90% influence on the hardness property. These dominating potentials of these two parameters limited the interaction of the parameters studied in the research. statistical analysis. As regards the tensile strength of the test castings, the geometry of components (GOC) dominated, contributing 90.83% and the pouring temperature (PT) contributed 91.90% influence on the hardness property. These dominating potentials of these two parameters limited the interaction of the parameters studied in the research.

14

Statistical Evaluation of Variation of the River Bug Water Chemical Contamination

Rymuza Katarzyna, Radzka Elżbieta

Rocznik Ochrona Środowiska

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2019

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Tom 21, cz. 1

672--690

EN

The work presents analysis of chemical condition of the water of the River Bug stretch extending from Kiryłowo to Krzyszew. The analysis was preformed based on data of monitoring of surface water quality available on the website of Voivodeship Inspectorate of Environmental Protection in Lublin (WIOŚ) spanning the years 2015-2017. Eight measurement points and the following months were considered: February, April, June, August, October and December. Analysis of variance and Kruskal-Wallis test were used to analyse the effect of localities and months on selected chemical indicators. The concentrations of nearly all the parameters (excluding BOD) were found to be influenced by the localities. Phosphorus content, sulphates and chlorides increased along the course of the river. Also, the analysis revealed that the concentration of ammonium ions, dissolved oxygen, sulphates and chlorides increased in winter. Multidimensional analysis demonstrated that differences in chemical conditions between the localities were predominantly due to nitrogen compound content, total phosphorus content and chlorides. Cluster analysis showed that in nearly all the months (excluding August) the tested stretch of the River Bug could be divided into two parts with different chemical composition parameters. The first part, characterised by higher average values of ammonium nitrogen content, dissolved oxygen content and total phosphorus content, included the following measurement points: Krzyszew, Kukuryki, Włodawa and Kuzawka. The second part was formed by the following localities: Kryłów, Zosin and Horodło, all with higher average BOD values, sulphates and chlorides.

PL

W pracy przedstawiano analizę chemicznego stanu wód rzeki Bug na odcinku od Kryłowa do Krzyszewa. Analizy tej dokonano na podstawie danych pochodzących z monitoringu jakości wód powierzchniowych zamieszczonych na stronie Wojewódzkiego Inspektoratu Ochrony Środowiska w Lublinie (WIOŚ) z lat 2015-2017. Pod uwagę wzięto dane z lutego, kwietnia, czerwca, sierpnia, października i grudnia z 8 punktów pomiarowych. Przy pomocy analizy wariancji oraz testu Kruskala-Wallisa przeanalizowano wpływ miejscowości oraz miesięcy na zawartość wybranych wskaźników chemicznych. Stwierdzono, że zawartość prawie wszystkich parametrów (poza BZT5) różnicowana była przez miejscowości. Wraz z biegiem rzeki zmniejszała się zawartość fosforu, siarczanów i chlorków. Analiza wykazała ponadto, że zimą rosło stężenie jonów amonowych, zawartość tlenu rozpuszczonego, siarczanów i chlorków. Wielowymiarowa analiza natomiast dowiodła, że różnice stanu chemicznego pomiędzy miejscowościami związane były głównie z zawartością związków azotu, fosforu ogólnego oraz chlorków. Na podstawie analizy skupień prawie we wszystkich miesiącach (poza sierpniem) odcinek rzeki Bug pod względem stanu chemicznego można podzielić na dwie części. Pierwszą grupę stanowi odcinek rzeki z punktami pomiarowymi w Krzyszewie, Kukurykach, Włodawie i Kuzawce o większych średnich zawartościach azotu amonowego, tlenu rozpuszczalnego i fosforu ogólnego. Drugą grupę utworzyły miejscowości: Kryłów, Zosin i Horodło o wyższych średnich stężeniach BTZ5, siarczanów i chlorków.

15

Comparison of information on sleep apnoea contained in two symmetric EEG recordings

Prucnal Monika A., Polak Adam G.

Metrology and Measurement Systems

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2019

|

Vol. 26, nr 2

229--239

EN

Electroencephalogram (EEG) is one of biomedical signals measured during all-night polysomnography to diagnose sleep disorders, including sleep apnoea. Usually two central EEG channels (C3-A2 and C4-A1) are recorded, but typically only one of them are used. The purpose of this work was to compare discriminative features characterizing normal breathing, as well as obstructive and central sleep apneas derived from these central EEG channels. The same methodology of feature extraction and selection was applied separately for the both synchronous signals. The features were extracted by combined discrete wavelet and Hilbert transforms. Afterwards, the statistical indexes were calculated and the features were selected using the analysis of variance and multivariate regression. According to the obtained results, there is a partial difference in information contained in the EEG signals carried by C3-A2 and C4-A1 EEG channels, so data from the both channels should be preferably used together for automatic sleep apnoea detection and differentiation.

16

Statistical analysis of impact of visual impairment on postural stability

Jureczko M., Jureczko P.

Modelowanie Inżynierskie

|

2018

|

T. 38, nr 69

37--42

EN

The main aim of the presented research was assessment of postural stability in patients with various degree of visual impairment. The article contains basic explanation and requirements for stabilography research. Statistical analysis of impact of degree of visual impairment on postural stability opposed to people perfectly sighted was also conducted. The studies were conducted on 45 patients with various degree of visual impairment and 15 patients perfectly sighted. Postural stability was tested using diagnostic platform Zebris. The test results showed relationship between postural stability and degree of impairment and in line with them it can be stated that visual control has a significant impact on stability.

PL

Głównym celem przeprowadzonych badań była ocena stabilności postawy u pacjentów z różnym stopniem niepełnosprawności wzrokowej. Artykuł zawiera podstawowe wyjaśnienia i wymagania dotyczące badań nad stabilografią. Przeprowadzono analizę statystyczną wpływu stopnia upośledzenia wzroku na stabilność postawy w stosunku do osób doskonale widzących. Badania przeprowadzono na 45 pacjentach z różnym stopniem zaburzeń widzenia i 15 doskonale widzących. Stabilność postawy testowano przy użyciu urządzenia diagnostycznego firmy Zebris. Przeprowadzone badania dały wyniki pokazujące wpływ stopnia upośledzenia wzroku na stabilność postawy człowieka. Badania wykazały, że kontrola wizualna ma znaczący wpływ na stabilność człowieka.

17

Investigation of surface roughness and material removal rate on machining of TiB2 reinforced aluminum 6063 composites: A Taguchi's approach

Emmanual L., Karthikeyan T.

Mechanics and Mechanical Engineering

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2018

|

Vol. 22, nr 4

1319--1327

EN

The utilization of TiB2 particles reinforced aluminum (Al6063) metal matrix composite materials in many different engineering fields has undergone a tremendous increase. Accordingly, the need of accurate machining of composites has increased enormously; an attempt has been made to assess the factors influencing surface roughness and material removal rate on machining the composite. The orthogonal array, the signal-to-noise ratio, and analysis of variance were employed to study the performance characteristics in turning operations of 5 and 10 wt. % TiB2 particles reinforced aluminum (Al6063) metal matrix composites. Taguchi method was used to find the optimal cutting factors for surface roughness (Ra) and material removal rate (MRR). Three cutting factors namely speed; feed and depth of cut were optimized with considerations of Ra and MRR. The experimental plan and analysis was based on the Taguchi L27 orthogonal array with three cutting factors using carbide tool (K20). The optimal parametric combination for K20 carbide insert was found to be feed, speed and depth of cut. The analysis of variance (ANOVA) result shows that feed the most significant process parameter on surface roughness followed by speed. For MRR result show that the speed and the feed are the significant parameters followed by the composition of composite material.

18

Dynamika zmian cen za dostawę wody i odprowadzanie ścieków w Polsce w latach 2013-2017

Burszta-Adamiak E., Juszczyk M.

Instal

|

2018

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nr 6

50--55

PL

W artykule przedstawiono wyniki analiz poziomu oraz tempa zmian cen naliczanych w latach 2013-2017 przez przedsiębiorstwa wodociągowo-kanalizacyjne na terenie kraju za zbiorowe zaopatrzenie w wodę i odprowadzanie ścieków bytowych oraz opadowych i roztopowych. Wysokości cen porównano z uwzględnieniem analizowanych lat, liczby ludności w miastach oraz podziału terytorialnego (miasta wojewódzkie). Do oceny wpływu wielkości miasta na kształtowanie się cen za wodę i ścieki wykorzystano jednoczynnikową analizę wariancji (ANOVA). Wyniki badań wykazują, że w analizowanym okresie tempo wzrostu stawek za ścieki było większe niż za wodę. Największa dynamika cen w każdym rodzaju medium zachodziła w latach 2014-2016. Przebieg tych zmian w kolejnych latach rozliczeniowych (po 2017 roku) będzie uzależniony nie tylko od sytuacji organizacyjnej i ekonomicznej w przedsiębiorstwach, ale także od stopnia realizacji zapisów znowelizowanych aktów prawnych.

EN

The paper presents the results of analyses of price rates, charged by water and sewage companies in Poland, for collective water supply and disposal of domestic wastewater, rainwater and snowmelt in the period of 2013-2017. Price comparisons were made taking into account the analyzed years, population in cities and territorial division (voivodship cities). As part of the analysis, a one-way analysis of variance (ANOVA) was used to assess the impact of city size on the prices of water and sewage. The results show that the price increase rate of wastewater disposal was higher than the one of water supply services. The greatest rate of change for both utilities was noted in 2014- 2016. Organizational and economic structures of companies and the progress of implementing amended new regulations will influence on the course of price changes in forthcoming years (after 2017).

19

Surface quality by human inspection

Dekomien K., Huxol A., Riegel A., Ravichandran S., Wagenführ A.

Farby i Lakiery

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2018

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nr 3

42--52

EN

Quality plays a vital role for satisfying the customers and for measuring the reliability of the product. Looking at high gloss surfaces gives an idea of the difficulties in quality inspection. While common measurement techniques like gloss or color measurement are widely used in industry for quality assessment of furniture high gloss surfaces, they indicate only a weak correlation to the quality perceived by the customer. Thus different methods for measurement and sensory evaluation need to be qualified for the application on high gloss surfaces. This report shows how the surface quality of high gloss coated wooden products can be evaluated by means of visual inspection. The evaluation quality is controlled by a developed topography based measuring system. It is possible to find out the reproducibility and repeatability of the operators by implementing six sigma tools such as Analysis of Variance (ANOVA) and Measurement System Analysis (MSA). This method will be highly helpful in the wooden industries since the quality cannot be totally measured, is assessed based on required parameters and it also uses a Hedonic scale for calculating the results, which is quite easier and faster than other methods.

PL

Jakość odgrywa istotną rolę w zaspokajaniu potrzeb klientów i oceny niezawodności produktu. Patrząc na powierzchnie o wysokim połysku mamy wyobrażenie o trudnościach w ich kontroli jakości. Powszechne techniki pomiarowe, takie jak pomiar połysku lub barwy, są szeroko stosowane w przemyśle do oceny jakości powierzchni o wysokim połysku. Wykazują one jednak jedynie słabą korelację z jakością postrzeganą przez klienta. Dlatego też do oceny powierzchni o wysokim połysku muszą być stosowane różne metody pomiaru i oceny sensorycznej. W artykule przedstawiono, w jaki sposób jakość powierzchni drewnianych, powlekanych produktów o wysokim połysku można zbadać za pomocą oceny wizualnej. Jakość oceny jest kontrolowana przez opracowany system pomiaru oparty na topografii. Możliwe jest ustalenie odtwarzalności i powtarzalności operatorów za pomocą narzędzi Six Sigma, takich jak analiza wariancji (ANOVA) i analiza systemu pomiarowego (MSA). Metoda ta będzie bardzo pomocna w przemyśle drzewnym, ponieważ jakość nie może być w pełni zmierzona. Jest ona oceniana na podstawie wymaganych parametrów, a do obliczenia wyników stosuje się skalę hedoniczną, która jest znacznie łatwiejsza i szybsza niż w przypadku innych metod.

20

Analiza wariancji prędkości statków na Zatoce Pomorskiej w wybranych okresach

Kasyk L., Bugajski G.

Autobusy : technika, eksploatacja, systemy transportowe

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2017

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R. 18, nr 12

946--949, CD

PL

W artykule przedstawiono jednoczynnikową analizę wariancji prędkości statków na Zatoce Pomorskiej w kolejnych tygodniach stycznia i lutego 2017 roku. Zweryfikowano hipotezę o równości przeciętnych prędkości statków w poszczególnych tygodniach, sprawdzając najpierw założenia niezbędne do przeprowadzenia testu ANOVA. Do sprawdzenia normalności rozkładów wykorzystano testy Cramera von Misesa i Andersona-Darlinga, a do oceny jednorodności wariancji posłużył test Lavene’a.

EN

In this paper one-factor, fixed-effects completely randomized design of analysis of variance for vessel speed on the Pomeranian Bay has been presented. The hypothesis on the equality of the vessel speed means in nine weeks in January and February 2017 has been verified. To verify normality of distributions tests Cramer von Mises and Anderson-Darling have been used. To assess the equality of variances Levene’s test has been used.