Magazine et Edition

Volume 28 (2022): Edition 3 (September 2022)

Volume 28 (2022): Edition 2 (June 2022)

Volume 28 (2022): Edition 1 (March 2022)

Volume 27 (2021): Edition 4 (December 2021)

Volume 27 (2021): Edition 3 (September 2021)

Volume 27 (2021): Edition 2 (June 2021)

Volume 27 (2021): Edition 1 (March 2021)

Volume 26 (2020): Edition 4 (December 2020)

Volume 26 (2020): Edition 3 (September 2020)

Volume 26 (2020): Edition 2 (June 2020)

Volume 26 (2020): Edition 1 (March 2020)

Volume 25 (2019): Edition 25 (December 2019)

Volume 24 (2019): Edition 24 (September 2019)

Volume 23 (2019): Edition 23 (June 2019)

Volume 22 (2019): Edition 22 (March 2019)

Volume 21 (2018): Edition 21 (December 2018)

Volume 20 (2018): Edition 20 (September 2018)

Volume 19 (2018): Edition 19 (June 2018)

Volume 18 (2018): Edition 18 (March 2018)

Volume 17 (2017): Edition 17 (December 2017)

Volume 16 (2017): Edition 16 (September 2017)

Volume 15 (2017): Edition 15 (June 2017)

Volume 14 (2017): Edition 14 (March 2017)

Détails du magazine
Format
Magazine
eISSN
2353-7779
Première publication
30 Mar 2018
Période de publication
4 fois par an
Langues
Anglais

Chercher

Volume 26 (2020): Edition 2 (June 2020)

Détails du magazine
Format
Magazine
eISSN
2353-7779
Première publication
30 Mar 2018
Période de publication
4 fois par an
Langues
Anglais

Chercher

8 Articles
Accès libre

Building decision trees based on production knowledge as support in decision-making process

Publié en ligne: 25 Jun 2020
Pages: 36 - 40

Résumé

Abstract

The article presents sources of production knowledge and thoroughly describes its identification which on the construction of decision trees, and on the construction of knowledge bases for production processes. The problems that arise during the technical preparation of production are briefly characterized and the advanced algorithm with which decision trees can be built is described in detail. A decision tree was built based on real data from the manufacturing company. Decision trees are presented as a method of knowledge representation.

Mots clés

  • decision trees
  • knowledge identification
  • production engineering
  • production knowledge
  • production processes
Accès libre

Microstructure and residual stress analysis of Strenx 700 MC welded joint

Publié en ligne: 25 Jun 2020
Pages: 41 - 44

Résumé

Abstract

High strength low alloy (HSLA) steels are a new generation of plain carbon steels with significantly improved mechanical properties while maintaining good weldability with common commercial techniques. Residual stress and microstructural analysis of welded HSLA Strenx 700 MC was carried out in this research. Results have shown that the welding process causes significant grain coarsening in the heat affected zone. The microstructural changes are also accompanied with creation of tensile residual stress field in the weld metal and heat affected zone, reaching up-to depth of 4 mm. Tensile residual stresses are well known for acceleration of fatigue crack initiation and together with coarse grains can lead to significant decrease of the fatigue properties of the welded structure.

Mots clés

  • Residual stress
  • High strength steel
  • Welding
  • Microstructure
  • Grain coarsening
Accès libre

Identification of health risks from harmful chemical agents – review concerning bisphenol A in workplace

Publié en ligne: 25 Jun 2020
Pages: 45 - 49

Résumé

Abstract

Bisphenol A (BPA) is an industrial chemical used as an additive in conventional point-of-sale thermal paper receipts, in the production of many polycarbonate plastics, and epoxy resins lignin for food. BPA is xenoestrogen, a foreign compound that is not naturally produced in living organisms, but which acts similarly to natural 17-ß estradiol (natural estrogen). Due to its weak estrogenic activities, BPA exposure may influence multiple endocrine-related pathway, and is associated with prostate and breast cancer, neurobehavioral deficits, heart disease, and obesity. Furthermore, BPA may act as a DNA methylation agent and cause altered gene expression in the brain. Human exposure to bisphenol A is a matter of controversy. This review shows a potential risks in workplace resulting from contact with bisphenol A. The work presents the contribution of BPA exposure levels via dermal contact and the relationship between BPA exposure level and oxidative DNA damage.

Mots clés

  • bisphenol A
  • health risk
  • harmful chemical agents
  • human exposure
  • DNA oxidative damage
Accès libre

Quality management and safety of food in HACCP system aspect

Publié en ligne: 25 Jun 2020
Pages: 50 - 53

Résumé

Abstract

The practical implementation of hazard analysis and critical control point (HACCP) and in particular the definition of the critical control points (CCPs) in the food industry is usually a complex structured task. This is particularly the case of food enterprise, where quality/safety manager ability, knowledge of the production processes and ‘‘sensitiveness’’ is usually the discriminate for the proper identification and prioritization of risks. The same applies for the definition of causes which may lead to food safety hazards. This paper addresses the issues of how quality/safety managers can objectively and automatically implement the HACCP principles of hazard analysis in the application of HACCP, which is the identification of risk priorities and of the related CCPs. The proposed methodology combines decision tree analysis approach for the analytical decomposition of the relevant steps in the manufacturing process of ice cream.

Mots clés

  • quality
  • HACCP system
  • safety of food
  • quality systems
  • competition
Accès libre

Thermal fracture characteristics of an interface crack subjected to temperature variations

Publié en ligne: 25 Jun 2020
Pages: 54 - 59

Résumé

Abstract

Thermal fracture characteristics – the thermal energy release rate and thermal stress intensity factor of a semi-infinite crack at an interface between the two elastic isotropic materials, subjected to the temperature variations, are considered in this paper. Those characteristics are determined based on application of the linear elastic fracture mechanics (LEFM) concept. Expressions for obtained theoretical solutions are compared to solutions from literature and they are found to be more concise. Influence of the materials change on these two thermal fracture properties were observed, as well as the influence of the thickness ratio of the two layers constituting the interface.

Mots clés

  • Interface crack
  • Two-layered sample
  • Temperature variation
  • Fracture properties
  • LEFM concept
Accès libre

Cost-quantitative analysis of non-compliance in the internal logistics process

Publié en ligne: 25 Jun 2020
Pages: 60 - 66

Résumé

Abstract

Internal logistics is a key element of a production process as it specifies product quality, timeliness and value of orders. The purpose of the research was to determine the amount of non-compliance in the selected production process caused by internal logistics operations. The analysis covers both the quantity and type of non-compliance as well as the cost of non-compliance. One of the basic quality management tools was used in the research - Parteo-Lorenz analysis. An attempt was made to identify potential causes of non-compliance. The significant impact of non-compliance arising in internal logistics operations in production costs was pointed out.

Mots clés

  • quality
  • cost
  • internal logistics process
  • Parteo-Lorenz analysis
Accès libre

Non-uniform corrosion of steel rebar and its influence on reinforced concrete elements` reliability

Publié en ligne: 25 Jun 2020
Pages: 67 - 72

Résumé

Abstract

Remarkable place of reinforced concrete structures in construction field has been noted in wide number of recent researches. Subsequently, their degradation due to aggressive environment has become the topical problem nowadays. Therefore, the formulation of reliable technique for corroded element strength decrement is of great importance, and could be achieved only with the use of complex experimental and theoretical analysis. In this article an attempt is made to propose the mathematical approach to corrosive process modelling, taking into consideration the specifics of its development. According to thorough literature review on existing studies, main specifics of the process were indicated for further suppositions and assumptions formulation. Accordingly, the complex theoretical investigation with corresponding mathematical computations was conducted and results of analytical modelling were discussed. As the initial data for analytical modelling results of previously conducted experiments were used. Analysis of the obtained results shows rather high correspondence with the real conditions of structural element exploitation, taking into consideration material anisotropy and complexity of the corroded zone spread along the rebar cross-section. Proposed methodology for limit force decrease evaluation in general demonstrates reliable results and could be used for further evaluation of corrosion impacts on reinforced concrete elements bearing capacity.

Mots clés

  • corrosion
  • steel rebar
  • material anisotropy
  • mathematical modelling
Accès libre

Standardization of human activities as the component of a workflow efficiency model – a research experiment from a meat producing plant

Publié en ligne: 25 Jun 2020
Pages: 73 - 77

Résumé

Abstract

The aim of the following research it to provide assumptions for creating workflow efficiency model that can be implemented in repeatable production workstations. One of the main components of this model are human activities and their interactions with other elements of working environment: human and artefacts. Recognition of patterns of human behaviours within working processes gives the opportunity to find critical points that influence workflow efficiency.

The subject of research is a working process existing in meat producing plant. The main method used for recognizing human activity patterns was observation and qualitative and quantitative assessments of operational activities based on video registration. Particularly, human activities were analyzed under ergonomics criteria in order to proof dependencies between process efficiency and specific ergonomic factors forming working conditions at meat plant.

Mots clés

  • workflow
  • standardization
  • ergonomics
  • patterns of activities
  • efficiency
8 Articles
Accès libre

Building decision trees based on production knowledge as support in decision-making process

Publié en ligne: 25 Jun 2020
Pages: 36 - 40

Résumé

Abstract

The article presents sources of production knowledge and thoroughly describes its identification which on the construction of decision trees, and on the construction of knowledge bases for production processes. The problems that arise during the technical preparation of production are briefly characterized and the advanced algorithm with which decision trees can be built is described in detail. A decision tree was built based on real data from the manufacturing company. Decision trees are presented as a method of knowledge representation.

Mots clés

  • decision trees
  • knowledge identification
  • production engineering
  • production knowledge
  • production processes
Accès libre

Microstructure and residual stress analysis of Strenx 700 MC welded joint

Publié en ligne: 25 Jun 2020
Pages: 41 - 44

Résumé

Abstract

High strength low alloy (HSLA) steels are a new generation of plain carbon steels with significantly improved mechanical properties while maintaining good weldability with common commercial techniques. Residual stress and microstructural analysis of welded HSLA Strenx 700 MC was carried out in this research. Results have shown that the welding process causes significant grain coarsening in the heat affected zone. The microstructural changes are also accompanied with creation of tensile residual stress field in the weld metal and heat affected zone, reaching up-to depth of 4 mm. Tensile residual stresses are well known for acceleration of fatigue crack initiation and together with coarse grains can lead to significant decrease of the fatigue properties of the welded structure.

Mots clés

  • Residual stress
  • High strength steel
  • Welding
  • Microstructure
  • Grain coarsening
Accès libre

Identification of health risks from harmful chemical agents – review concerning bisphenol A in workplace

Publié en ligne: 25 Jun 2020
Pages: 45 - 49

Résumé

Abstract

Bisphenol A (BPA) is an industrial chemical used as an additive in conventional point-of-sale thermal paper receipts, in the production of many polycarbonate plastics, and epoxy resins lignin for food. BPA is xenoestrogen, a foreign compound that is not naturally produced in living organisms, but which acts similarly to natural 17-ß estradiol (natural estrogen). Due to its weak estrogenic activities, BPA exposure may influence multiple endocrine-related pathway, and is associated with prostate and breast cancer, neurobehavioral deficits, heart disease, and obesity. Furthermore, BPA may act as a DNA methylation agent and cause altered gene expression in the brain. Human exposure to bisphenol A is a matter of controversy. This review shows a potential risks in workplace resulting from contact with bisphenol A. The work presents the contribution of BPA exposure levels via dermal contact and the relationship between BPA exposure level and oxidative DNA damage.

Mots clés

  • bisphenol A
  • health risk
  • harmful chemical agents
  • human exposure
  • DNA oxidative damage
Accès libre

Quality management and safety of food in HACCP system aspect

Publié en ligne: 25 Jun 2020
Pages: 50 - 53

Résumé

Abstract

The practical implementation of hazard analysis and critical control point (HACCP) and in particular the definition of the critical control points (CCPs) in the food industry is usually a complex structured task. This is particularly the case of food enterprise, where quality/safety manager ability, knowledge of the production processes and ‘‘sensitiveness’’ is usually the discriminate for the proper identification and prioritization of risks. The same applies for the definition of causes which may lead to food safety hazards. This paper addresses the issues of how quality/safety managers can objectively and automatically implement the HACCP principles of hazard analysis in the application of HACCP, which is the identification of risk priorities and of the related CCPs. The proposed methodology combines decision tree analysis approach for the analytical decomposition of the relevant steps in the manufacturing process of ice cream.

Mots clés

  • quality
  • HACCP system
  • safety of food
  • quality systems
  • competition
Accès libre

Thermal fracture characteristics of an interface crack subjected to temperature variations

Publié en ligne: 25 Jun 2020
Pages: 54 - 59

Résumé

Abstract

Thermal fracture characteristics – the thermal energy release rate and thermal stress intensity factor of a semi-infinite crack at an interface between the two elastic isotropic materials, subjected to the temperature variations, are considered in this paper. Those characteristics are determined based on application of the linear elastic fracture mechanics (LEFM) concept. Expressions for obtained theoretical solutions are compared to solutions from literature and they are found to be more concise. Influence of the materials change on these two thermal fracture properties were observed, as well as the influence of the thickness ratio of the two layers constituting the interface.

Mots clés

  • Interface crack
  • Two-layered sample
  • Temperature variation
  • Fracture properties
  • LEFM concept
Accès libre

Cost-quantitative analysis of non-compliance in the internal logistics process

Publié en ligne: 25 Jun 2020
Pages: 60 - 66

Résumé

Abstract

Internal logistics is a key element of a production process as it specifies product quality, timeliness and value of orders. The purpose of the research was to determine the amount of non-compliance in the selected production process caused by internal logistics operations. The analysis covers both the quantity and type of non-compliance as well as the cost of non-compliance. One of the basic quality management tools was used in the research - Parteo-Lorenz analysis. An attempt was made to identify potential causes of non-compliance. The significant impact of non-compliance arising in internal logistics operations in production costs was pointed out.

Mots clés

  • quality
  • cost
  • internal logistics process
  • Parteo-Lorenz analysis
Accès libre

Non-uniform corrosion of steel rebar and its influence on reinforced concrete elements` reliability

Publié en ligne: 25 Jun 2020
Pages: 67 - 72

Résumé

Abstract

Remarkable place of reinforced concrete structures in construction field has been noted in wide number of recent researches. Subsequently, their degradation due to aggressive environment has become the topical problem nowadays. Therefore, the formulation of reliable technique for corroded element strength decrement is of great importance, and could be achieved only with the use of complex experimental and theoretical analysis. In this article an attempt is made to propose the mathematical approach to corrosive process modelling, taking into consideration the specifics of its development. According to thorough literature review on existing studies, main specifics of the process were indicated for further suppositions and assumptions formulation. Accordingly, the complex theoretical investigation with corresponding mathematical computations was conducted and results of analytical modelling were discussed. As the initial data for analytical modelling results of previously conducted experiments were used. Analysis of the obtained results shows rather high correspondence with the real conditions of structural element exploitation, taking into consideration material anisotropy and complexity of the corroded zone spread along the rebar cross-section. Proposed methodology for limit force decrease evaluation in general demonstrates reliable results and could be used for further evaluation of corrosion impacts on reinforced concrete elements bearing capacity.

Mots clés

  • corrosion
  • steel rebar
  • material anisotropy
  • mathematical modelling
Accès libre

Standardization of human activities as the component of a workflow efficiency model – a research experiment from a meat producing plant

Publié en ligne: 25 Jun 2020
Pages: 73 - 77

Résumé

Abstract

The aim of the following research it to provide assumptions for creating workflow efficiency model that can be implemented in repeatable production workstations. One of the main components of this model are human activities and their interactions with other elements of working environment: human and artefacts. Recognition of patterns of human behaviours within working processes gives the opportunity to find critical points that influence workflow efficiency.

The subject of research is a working process existing in meat producing plant. The main method used for recognizing human activity patterns was observation and qualitative and quantitative assessments of operational activities based on video registration. Particularly, human activities were analyzed under ergonomics criteria in order to proof dependencies between process efficiency and specific ergonomic factors forming working conditions at meat plant.

Mots clés

  • workflow
  • standardization
  • ergonomics
  • patterns of activities
  • efficiency

Planifiez votre conférence à distance avec Sciendo