rss_2.0Engineering FeedSciendo RSS Feed for Engineeringhttps://www.sciendo.com/subject/ENhttps://www.sciendo.comEngineering Feedhttps://www.sciendo.com/subjectImages/Engineering.jpg700700Remarks on bipolar cubic fuzzy graphs and its chemical applicationshttps://sciendo.com/article/10.2478/ijmce-2023-0001<abstract>
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<p>In theoretical chemistry, fuzzy molecular graphs can be used to model chemical molecular structures with uncertainty information, where the vertex membership function and edge membership function describe the uncertainty of atoms and chemical bonds respectively. This paper studies chemical topological index of bipolar cubic fuzzy graphs. The new concepts and theorems are given in terms of graph theory and fuzzy set theory approaches, and several theoretical conclusions on bipolar Wiener index of bipolar cubic fuzzy graphs are determined. Furthermore, we apply it in chemical science, and calculate the bipolar Wiener index of dimethyltryptamine and hallucinogen which are modelled by bipolar cubic fuzzy graphs.</p>
</abstract>ARTICLEtruehttps://sciendo.com/article/10.2478/ijmce-2023-00012023-03-28T00:00:00.000+00:00Global trends of the research on COVID-19 risks effect in sustainable facility management fields: a bibliometric analysishttps://sciendo.com/article/10.2478/emj-2023-0002<abstract>
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<p>This study used bibliometric analysis to investigate global research trends regarding the effect of COVID-19 risks in sustainable facility management fields. Between 2019 and 2021, the Scopus database published 208 studies regarding the effect of COVID-19 risks on sustainable facility control fields. VOSviewer software was used to analyse the co-occurrence of all keywords, and Biblioshiny software allowed getting the most relevant affiliation using the three-field plot. The results show the contribution by authors from 51 countries, and 73 keywords were identified and organised into six clusters, such as the effect of COVID-19 risks on human health, supply chain in construction projects and industry, disaster risk management in a changing climate, sustainable supply chain benchmarking, facility management and quality control, and, finally, sensitivity analysis & decision-making.</p>
</abstract>ARTICLEtruehttps://sciendo.com/article/10.2478/emj-2023-00022023-03-29T00:00:00.000+00:00IT reliability as a source of sustainability for organisations operating during the COVID-19 pandemichttps://sciendo.com/article/10.2478/emj-2023-0003<abstract>
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<p>The article aims to show that reliable IT support was crucial for the survival and sustainability of organisations during the COVID-19 pandemic. The article considers the negative effect of the crisis caused by the COVID-19 pandemic on the organisational sustainability of an organisation (i.e., organisational performance through employee job performance). It explores the role of IT reliability in mitigating such a negative effect. To verify the hypotheses, the empirical studies were performed during the COVID-19 crisis with 1160 organisations operating in Poland, Italy and the USA. The data were analysed using multiple linear regression models with mediators and moderators. The results confirmed that due to the ability to limit the severity of a crisis-induced negative effect on employee job performance (influencing organisational performance), IT reliability could be considered a mitigator for the negative effect of the COVID-19 crisis on the sustainability of organisations. The results indicate that IT reliability should be fostered among organisations operating during the COVID-19 pandemic to maintain sustainability.</p>
</abstract>ARTICLEtruehttps://sciendo.com/article/10.2478/emj-2023-00032023-03-29T00:00:00.000+00:00Exploring the usability and user experience of social media apps through a text mining approachhttps://sciendo.com/article/10.2478/emj-2023-0007<abstract>
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<p>This study aims to evaluate the applicability of a text mining approach for extracting UUX-related issues from a dataset of user comments and not to evaluate the Instagram (IG) app. This study analyses textual data mined from reviews in English written by IG mobile application users. The article’s authors used text mining (based on the LDA algorithm) to identify the main UUX-related topics. Next, they mapped the identified topics with known theoretical constructs to place them in their nomological network relevant to the usability (the 5Es framework by Quesenbery) and UX (the Honeycomb model by Morville). Finally, to expand the study with an emotional diagnosis, sentiment analysis was performed on two levels: (i) for each recognised topic, and (ii) for the full dataset to uncover general insights into users’ emotions within all reviews. The case study of the IG app confirms the usefulness of user feedback data for software development and points out that the review data have the potential for the early detection of frustration and negative feelings introduced during the use of the application. Conducting conventional UUX evaluations with users is problematic since they are remotely located, and the user-generated content of a social app undergoes continuous and frequent changes. Thus, the consecutive stages of the proposed methodology, based on text mining algorithms, constitute a proposed framework for examining the user-perceived quality projection of applications from user feedback, and they are the main contribution of this article. The used approach can be valuable for helping developers, designers and researchers to reveal user problems and fulfil user satisfaction regarding UUX aspects for specific software features.</p>
</abstract>ARTICLEtruehttps://sciendo.com/article/10.2478/emj-2023-00072023-03-29T00:00:00.000+00:00Characterising project management of lean initiatives in industrial companies — crossing perspectives based on case studieshttps://sciendo.com/article/10.2478/emj-2023-0005<abstract>
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<p>The paper mainly aims to characterise project management (PM) practices of industrial Lean initiatives by analysing and comparing three main topics: PM approaches, PM teams, and project alignment with the company’s strategy. This research encompasses two exploratory industrial case studies with an extensive literature review. Key professionals were interviewed to obtain an in-depth vision of the field. The study results allowed characterising project management practices of industrial Lean initiatives in industrial companies based on the following dimensions: 1. Understand the needs; 2. Find a suitable team; 3. Use visual tools; 4. Apply a continuous improvement (CI) approach; 5. Identify KPIs for the context; 6. Get support from the top management. This work fills a gap related to studying the PM practices applied during the implementation of Lean initiatives, proposing a schematic representation of PM variables and actors in industrial Lean initiatives. Identifying the main variables and actors that industrial companies use to develop Lean initiatives can be insightful for Lean practitioners in the context of project management.</p>
</abstract>ARTICLEtruehttps://sciendo.com/article/10.2478/emj-2023-00052023-03-29T00:00:00.000+00:00Impact of cash flow variation on project performance: contractors’ perspectivehttps://sciendo.com/article/10.2478/emj-2023-0006<abstract>
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<p>This study aims to determine the impact of cash flow variation in Jordanian construction projects from contractors’ perspective and its relationship with project performance. An online questionnaire was developed and distributed to a selective sample. The respondents were project managers from contracting companies working in Jordan, around 340 construction companies. The sample frame was a form of non-probability sampling of 181 project managers. The collected data were analysed using the Statistical Package of the Social Sciences (SPSS) version 25. The study results showed a positive statistically significant effect at the significance level (α ≤0.05) of cash flow variation on project performance in Jordanian construction projects. In addition, respondents indicated a high level of agreement on the impact of cash flow variation on projects’ performance, with a mean of 4.01 and a standard deviation of .546. However, on the project performance dimensions’ level, Quality came first, with a mean of 4.11 and at a high level, followed by Safety, with a mean of 4.01 and at a high level, while Final Cost ranked third with a mean of 3.96 and at a high level. Finally, Project Final Duration ranked fourth with a mean of 3.95. The researchers recommended the necessity of more efforts for a better understanding of the importance of cash flow by contractors to schedule project activities correctly and efficiently to maintain a steady state of the project cash flow.</p>
</abstract>ARTICLEtruehttps://sciendo.com/article/10.2478/emj-2023-00062023-03-29T00:00:00.000+00:00Exploring the critical success factors of a resilient supply chainhttps://sciendo.com/article/10.2478/emj-2023-0004<abstract>
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<p>This study aims to identify and analyse critical success factors (CSFs) for an organisation aiming for a resilient supply chain. The methodology followed is the systematic analysis of big databases, such as Emerald, Science Direct, and Taylor & Francis, by using a specific set of keywords for filtering. The systematic literature review leads the author to the exploration of several CSFs, followed by their prioritisation by using principal component analysis. The paper highlighted eleven vital CSFs: top management commitment, development of an effective SCM strategy, logistics synchronisation, use of modern technologies, robust information and communication technology, information sharing with SC members, collaborative partnership, improved forecasting, trust development in SC partners, collaborative partnership, strategic partnership, development of reliable suppliers, continuous improvement in the preparedness and response practices, capacity building and training and staff development. The CSFs highlighted in the paper relate to all small and medium-sized enterprises (SMEs). This paper identifies the CSFs for developing a resilient supply chain that is comprehensive and has the potential to address uncertain circumstances. This work is the first of its kind on CSF assessment and categorisation in resilient supply chains.</p>
</abstract>ARTICLEtruehttps://sciendo.com/article/10.2478/emj-2023-00042023-03-29T00:00:00.000+00:00Teleworking and sustainable behaviour in the context of COVID-19: the case of Lithuaniahttps://sciendo.com/article/10.2478/emj-2023-0001<abstract>
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<p>COVID-19 played a significant role in the spread of telework worldwide, changing people’s lives and behaviour. The paper aims to identify how teleworking affected the sustainable behaviour of employees during the COVID-19 pandemic. The research design applies a multi-method approach, combining systematic and comparative scientific literature analysis and a semi-structured interview. The authors of the paper present the theoretical conceptual model, which illustrates links between teleworking during the COVID-19 pandemic and the sustainable behaviour of employees. The results of empirical research revealed that teleworking during the COVID-19 pandemic changed employee behaviour in economic, environmental and social dimensions. Positive changes were identified due to reduced commuting and shopping; decreased costs for transport, food, clothing, and beauty services; better access to healthy and nutritious food; better opportunities for professional development. On the contrary, costs for home energy and household waste increased. Adverse effects on employees’ physical and mental health have been identified due to teleworking and COVID-19. Despite the identified negative effects, employees would like to continue teleworking even after the pandemic.</p>
</abstract>ARTICLEtruehttps://sciendo.com/article/10.2478/emj-2023-00012023-03-29T00:00:00.000+00:00Numerical and Experimental Investigation of Bonding Evolution of Bi-Metal Al/Br Laminates Fabricated Via Asymmetric Roll Bondinghttps://sciendo.com/article/10.2478/ata-2023-0008<abstract>
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<p>Materials and alloys usually possess distinct properties. In contrast to conventional materials, employment of bi-metal laminates allows achievement of better performance in various properties, such as light density, high strength, high corrosion and wear resistances. Moreover, considering the agriculture machinery and equipment, there is a growing demand for utilization of advanced materials with improved mechanical properties and durability. Bonding (RB) process is one of the new novel methods for production of bi-metal laminates. The study presented explores the asymmetric roll bonding for the purposes of fabrication of bi-metal Al/Br laminates with thickness reduction ratios 10–30% with mismatch speed ratios of 1 : 1.05, 1 : 1.1 and 1 : 1.15. Furthermore, finite element simulation of roll bonding process was investigated using ABAQUS software. Additionally, to improve the bonding strength, the effect of mismatch speed ratios was investigated. Finally, utilizing the scanning electron microscopy (SEM), the bonding surface morphology of samples was studied.</p>
</abstract>ARTICLEtruehttps://sciendo.com/article/10.2478/ata-2023-00082023-03-27T00:00:00.000+00:00Influence of Agrotechnical Practices and Sowing Time in Various Weather on Soybean Yieldhttps://sciendo.com/article/10.2478/ata-2023-0002<abstract>
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<p>For seed germination and the formation of a good soybean crop, significant reserves of soil moisture are required, which depends on the autumn-winter soil preparation, weather conditions and planting dates. The purpose of this study is to identify the impact of the main tillage technology on its agrophysical properties and conditions for the growth and development of soybean plants. Experimental crop rotation: soybean – winter wheat was carried out under favourable (hydrothermal coefficient 1.46) and dry (hydrothermal coefficient 0.66–0.87) weather conditions. The main tillage was carried out with a stratifier PRSM-5 to a depth of 15–17 cm or a chisel plough PCh-2.5 to a depth of 25–27 cm, with additional pre-sowing or post-sowing rolling with a ring-spur roller KKSH. Sowing was carried out at a depth of 10 cm with stable heating of the soil in three periods: the first at 8–10 °С, the second at 10–12 °С, and the third at 12–14 °С. As a result of evaluating the influence of various factors, it was found that under favourable conditions, the highest seed productivity of soybean plants (1.91–1.96 t·ha<sup>−1</sup>) was formed after treatment with the stratifier PRSM-5 at the first sowing period and at the second sowing period after chisel ploughing with additional soil compaction. In dry weather conditions, pre-sowing treatment with a stratifier PRSM-5 had an advantage in seed productivity by 7–12% compared to ploughing with a chisel plough PCH-2.5.</p>
</abstract>ARTICLEtruehttps://sciendo.com/article/10.2478/ata-2023-00022023-03-27T00:00:00.000+00:00Modelling of Impulse Functions of Ultrasonic Sensors When Tilt Angle of Reflecting Surface is Changedhttps://sciendo.com/article/10.2478/ata-2023-0001<abstract>
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<p>Increasing the accuracy of position measurement is an intensively addressed issue in engineering practice. Indirect methods provide satisfactory distance information. For more accurate identification of surface geometry or tilt, systems based on image processing are frequently employed, however, these are more expensive in contrast to devices operating on the basis of acoustic principle. This paper deals with the modelling of the impulse functions of ultrasonic sensors under known geometrical conditions of their distribution. The reflecting surface is a metallic surface. Based on the results, a statistically significant non-linear correlation between the complex integral of the impulse function and the front time of the transient characteristic is shown. The change from the parallel to the perpendicular case of the longitudinal axis of ultrasonic transducer distribution due to the change in the tilt angle of reflected surface is also included in the study. The interval of change in the tilt angle of reflecting surface was from 0° to 30°.</p>
</abstract>ARTICLEtruehttps://sciendo.com/article/10.2478/ata-2023-00012023-03-27T00:00:00.000+00:00Possibilities of Noise Load Elimination in Productionhttps://sciendo.com/article/10.2478/ata-2023-0006<abstract>
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<p>In a pleasant and healthy work environment, employees are able to fully devote themselves to work, which is reflected in their work performance and a positive approach to work. This research paper focuses on changing the management approach of a selected company to physical factors of the work environment. The focus was targeted at looking for possibilities to change the work environment, which would create wellbeing for its employees, as well as to the exposure of a worker to noise in the work environment and the possibility of its elimination in a particular manufacturing plant. Based on measurements it was found out that the noise exposure values on the machinery had been exceeded. Based on the findings, two corrective technical measures were proposed to reduce noise in the workplace. The first technical measure was to cover the ultrasonic welders with acoustic covers; the second was to cover the fixture itself. However, the fixture covering was removed due to several negative effects on labour productivity and increased costs. After the implementation of technical measures, the measurements were taken once again and based on the results, the organizational measures were proposed.</p>
</abstract>ARTICLEtruehttps://sciendo.com/article/10.2478/ata-2023-00062023-03-27T00:00:00.000+00:00The Crop Coefficient of Ginger ( var. ) during Vegetative Growth in Eastern Indonesiahttps://sciendo.com/article/10.2478/ata-2023-0005<abstract>
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<p>Ginger (<italic>Zingiber officinale</italic> var. <italic>rubrum</italic>) is a rhizome plant that can benefit health, fitness and be used as a spice. The content contained in ginger can prevent and treat various diseases and act as an antioxidant and anti-inflammatory agent. The cultivation of ginger plants requires adequate nutrients and water for development and growth. Crop water requirements are influenced by crop coefficients which vary according to the plant growth stage. The crop coefficient values are needed for irrigation management and increasing irrigation efficiency. The main objective of the current study was to investigate the crop coefficient value of ginger by lysimeter. Lysimeter is a water balance device with the principle of mass conservation, where the input is rainfall and irrigation while the output is percolation and evapotranspiration. The rainfall during the investigated period was 0–62.82 mm·day<sup>−1</sup>, humidity 70.7–89.4%, and air temperature 23.7–32.9 °C. The crop coefficient of ginger increased during the vegetative growth period, i.e., 0.997 in the seedling stage, 1.072 in the tiller stage, and 1.138 in the advanced vegetative stage. The crop coefficient of red ginger was determined using a lysimeter quite accurately, with a coefficient of determination value (<italic>R</italic><sup>2</sup>) 0.950 and a significant value of <italic>F</italic> less than 0.05.</p>
</abstract>ARTICLEtruehttps://sciendo.com/article/10.2478/ata-2023-00052023-03-27T00:00:00.000+00:00Life Cycle Assessment of a Hybrid Self-Power Diesel Enginehttps://sciendo.com/article/10.2478/ata-2023-0003<abstract>
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<p>In the present study, an attempt was made to simulate the hybrid self-power generation process from a diesel engine and propose sustainable power-share management for this self-power hybrid electrical-diesel platform from the viewpoints of environmental and economic aspects (life cycle perspective). This concept means that when the engine works at part-load condition, we need to bring the engine operating conditions to optimal load, and along with doing the necessary work, in parallel, the rest of the power be used to generate electricity to be stored in the battery for more consumption in addition to reducing pollution and reducing fuel consumption by moving towards sustainable energy production. This case study examines the differences between using a diesel engine at idle and maximum load conditions when less engine power is required and if using a diesel engine in a diesel-electricity hybrid cycle. According to the obtained results, it can be concluded that to achieve the most negligible environmental impact, a lower share of generating power can be allocated to electricity generation in higher cycles than the share of generating electrical power in lower cycles. In other words, by increasing the engine speed, the amount of power consumption used to generate electricity relative to the power required from the diesel engine should be reduced so that the system suffers the most negligible environmental impact.</p>
</abstract>ARTICLEtruehttps://sciendo.com/article/10.2478/ata-2023-00032023-03-27T00:00:00.000+00:00The Effect of Tillage Method on the Nutrient Regime of Soil during the Growing of https://sciendo.com/article/10.2478/ata-2023-0004<abstract>
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<p>The article presents the results of studying the influence of tillage methods on the number of bacteria and fungi in the arable soil layer, nutrient indicators, and, consequently, the yield of <italic>Trifolium pratense</italic>. The purpose of the study is to determine how tillage affects the feeding regime and yield of <italic>Trifolium pratense</italic>. The research was conducted at the experimental field of the Educational and Scientific Research Center of Lviv National Environmental University. For the study of microorganisms in the arocenosis of meadow clover, soil samples were taken using a cylindrical drill from arable (0–20 cm) and sub-soil (20–40 cm) layers with an average weight of an individual sample of 300 g. For microbiological analysis, average samples from five individual samples were prepared. The isolation of the main agronomically useful groups of microorganisms from the soil was carried out by the method of microbiological sowing of soil extracts on solid nutrient media: for fungi – wort-agar, for bacteria – meat-peptone agar (MPA). The dilution of the soil extract for fungi and bacteria was, respectively, 1 : 1000; 1 : 100000. Microbiological seeding was performed in triplicate. The calculation of the total number of microorganisms in the soil was carried out by Tepper´s method. The yield of crops and the results of laboratory studies were processed by the method of variance analysis. The application of a tiered tillage allowed to increase the yield of <italic>Trifolium pratense</italic> green mass by 4.5 t·ha<sup>−1</sup> (+17.0%) compared to the control (conventional plowing). It is established that tier ploughing with the PYA-4-40 plough promotes uniform distribution of nutrients in the arable soil layer and formation of homogeneous soil fertility. In such a soil environment, much more favorable conditions are created for the development of microflora and more intensive microbiological processes compared to the options of chisel and conventional (control) tillage, and, consequently, the formation of high yields of green <italic>Trifolium pratense</italic>.</p>
</abstract>ARTICLEtruehttps://sciendo.com/article/10.2478/ata-2023-00042023-03-27T00:00:00.000+00:00Theoretical and Experimental Investigations of the Second Serve of Root Crop Pile Componentshttps://sciendo.com/article/10.2478/ata-2023-0007<abstract>
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<p>Fodder beet root crops in the autumn-winter period are one of the main types of juicy fodder for dairy livestock. Mechanized harvesting of fodder beet roots is a rather complex and energy-consuming technological process. The criteria that meet the requirements for the operation of root-harvesting machines are first of all the quality of digging and separation of impurities from root crops. The purpose of the work was improvement of the process of mechanized digging of fodder beets by an adapted digging-transport combined working body based on analytical and empirical research of the second feeds of constituent components of the dug pile of root crops. Based on the results of experimental studies, empirical regression equations were developed, which functionally describe the change in the second supply of the excavated components of the pile of root crops, depending on the speed of the root-harvesting machine and the rotation frequency of the drive shaft of the adapted digging-transport combined working body. Based on the comparative analysis, it was found that the discrepancy between the theoretical and approximated experimental values of second feeds is 5–10%. The results of the study are a further step in improving the method of optimizing the parameters of working bodies for digging and cleaning root crops from impurities.</p>
</abstract>ARTICLEtruehttps://sciendo.com/article/10.2478/ata-2023-00072023-03-27T00:00:00.000+00:00Simulation Time Reduction with 2.5D FEM Analysis for Axial Flux Machineshttps://sciendo.com/article/10.2478/pead-2023-0008<abstract>
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<p>In this paper, an approach for a two-and-half-dimensional (2.5D) finite element method (FEM)-based analysis, or quasi-three-dimensional (3D) FEM analysis, of an axial flux machine is discussed. By cutting the 3D model laterally and thereby creating cylindrical surface cuts, the 3D model can be split into several cylindrical surfaces. Transforming those cylindrical cuts into planes leads to a layer-based two-dimensional (2D) model with different radii for each layer. By integrating over all lateral surface cuts, the results for the entire axial flux machine can be determined. In comparison to the simulation of a full 3D FEM model, the simulation of the proposed 2.5D model is much faster. To validate the approach, the two main types of axial flux machines are simulated with both 3D-FEM-based model and 2.5D-FEM-based approach, and the results are presented in this paper.</p>
</abstract>ARTICLEtruehttps://sciendo.com/article/10.2478/pead-2023-00082023-03-26T00:00:00.000+00:00Clustering of Data Represented by Pairwise Comparisonshttps://sciendo.com/article/10.2478/candc-2022-0021<abstract>
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<p>In this paper, experimental data, given in the form of pairwise comparisons, such as distances or similarities, are considered. Clustering algorithms for processing such data are developed based on the well-known k-means procedure. Relations to factor analysis are shown. The problems of improving clustering quality and of finding the proper number of clusters in the case of pairwise comparisons are considered. Illustrative examples are provided.</p>
</abstract>ARTICLEtruehttps://sciendo.com/article/10.2478/candc-2022-00212023-03-22T00:00:00.000+00:00Readiness of Low Complexity ERP for Continuous Auditing in SMEs: The Brazilian Case Studyhttps://sciendo.com/article/10.2478/candc-2022-0022<abstract>
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<p>The continuous auditing technology assures integrity of accounting systems and consequently improves the decision-making process of the small and medium-sized enterprises (SMEs) that implement it. Considering that SMEs located in developing countries function within a more risk prone environment and do not have resources to implement all layers of customized corporate functions in information systems, one argues for their reliance on the features of low complexity of enterprise resource planning (ERP) software to benefit from continuous auditing (CA). The purpose of this study is to relate the understanding of the CA demands and low complexity ERP systems’ technical functionalities in SMEs. Thus, to fulfill this objective, a conceptual model has been drawn to integrate the key concepts related to CA. Four pillars are the core of this model, namely: segregation of duties (SoD) with role-based access control centered on process-based approach (PBA); internal checkpoints; audit trails; and the level of integration of the continuous auditing software. This model was validated through the benchmarking of the implementation of the pillars in three cases of low complexity ERP systems adopted by SMEs in a developing country. The benchmarking/results of the study show significant differences between operational mechanisms of the three ERP software. Namely, the role-based access control exists in the two of the ERP_LC but not in the Brazilian one. Also, there is no check-point in the Brazilian ERP_LC and it does not integrate with continuous audit features. This study distinguishes between the low complexity ERP’s functionalities and the features of a more complex environment, thus bringing an important contribution to the study of low complexity ERP’s readiness for continuous monitoring in SME’s internal auditing processes.</p>
</abstract>ARTICLEtruehttps://sciendo.com/article/10.2478/candc-2022-00222023-03-22T00:00:00.000+00:00Necessary and Sufficient Conditions for Constant Prices in a Sraffa’s Modelhttps://sciendo.com/article/10.2478/candc-2022-0020<abstract>
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<p>We give a simple and direct proof of necessary and sufficient conditions to have constant equilibrium prices in a simple Sraffa’s production model. We make some remarks on the linearity of the relation between profit rate and wage rate.</p>
</abstract>ARTICLEtruehttps://sciendo.com/article/10.2478/candc-2022-00202023-03-22T00:00:00.000+00:00en-us-1