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The purpose of this paper is to investigate the effect of remelting each layer on the homogeneity of nickel-titanium (NiTi) parts fabricated from elemental nickel and titanium powders using laser powder bed fusion (LPBF). In addition, the influence of manufacturing parameters and different melting strategies, including multiple cycles of remelting, on printability and macro defects, such as pore and crack formation, have been investigated.

An LPBF process was used to manufacture NiTi alloy from elementally blended powders and was evaluated with the use of a remelting scanning strategy to improve the homogeneity of fabricated specimens. Furthermore, both single melt and up to two remeltings were used.

The results indicate that remelting can be beneficial for density improvement as well as chemical and phase composition homogenization. Backscattered electron mode in scanning electron microscope showed a reduction in the presence of unmixed Ni and Ti elemental powders in response to increasing the number of remelts. The microhardness values of NiTi parts for the different numbers of melts studied were similar and ranged from 487 to 495 HV. Nevertheless, it was observed that measurement error decreases as the number of remelts increases, suggesting an increase in chemical and phase composition homogeneity. However, X-ray diffraction analysis revealed the presence of multiple phases regardless of the number of melt runs.

For the first time, to the best of the authors’ knowledge, elementally blended NiTi powders were fabricated via LPBF using remelting scanning strategies.

The purpose of this paper is to evaluate the eating habits of students in the field of management and engineering of food products compared to students from faculties not related to food science. Furthermore, another aim is to conduct gender-wise assessment to determine the type of eating habit, i.e., careful or binge eating.

The research involved 400 students from all years of study. The survey was conducted in 2017–2018 and the selection of the sample was intentional. The research used a questionnaire form. Additionally, χ² test was performed to assess the statistical independence of characteristics.

It is found that most students who pledge proper nutrition are women. The majority of respondents ate 3–4 meals in day and regular consumption of breakfast was declared among 42 percent of respondents. The consumption of sweet snacks between meals is reaffirmed by the half of the respondents. Students of the food sciences more often than others believed that they eat healthier and more regularly, although students of non-food directions most often declared intake of five or more meals a day.

An important limitation of the conducted study is a relatively small research sample. It consisted of university students from one of the largest academic centers in Poland. The results cannot be generalized to all students in this country. In the future, a similar survey should be conducted on a larger scale and cover all similar fields of management and engineering of food products in Poland. In addition, it would be worth expanding the research and examine graduates who found employment in the food industry.

The results of the conducted research are a good source of information on the differences in the way of feeding studying women and men. While such studies are not very revealing, the comparison between students in food and non-food fields can be considered a novelty. The described results can be used by the students themselves, but above all, by the authorities of universities conducting food science programs.

The students do not eat properly which can lead to nutritional deficiencies and can deteriorate mental and physical endurance damaging overall health.

The described research is important due to the observed deteriorating eating habits and growing overweight of young adults in developed countries like Poland. They show that education of food technologists, even at the academic level, does not always allow to avoid mistakes in their own nutrition.

The purpose of this paper is to present the varied roles played by the University of Lódz (UL) in maintaining and restoring the natural capital of a city as a driver for sustainable city development. The higher education institution can be perceived as visionary, originator and executor of natural capital projects.

The paper analyses three cases performed by the Faculty of Biology and Environmental Protection, UL, in the city of Lódz. The activities are based on different scales ranging from city-wide to local, e.g. river and green infrastructure, and which vary in character from policy planning to implementation.

Natural capital projects influence city development on different levels: by the initiation of legal protection, by the implementation of rehabilitation concepts for rivers and by influencing the strategic documents for mid-term and long-term urban development.

The university has the potential for multidisciplinary engagement in the development of urban sustainability. In large-scale projects, academics play a more conceptual role, in capacity building and knowledge transfer, while in local-scale implementations, their role includes innovation, know-how and technology transfer. Moreover, it may act as a reinforcement hub, by safeguarding and strengthening the natural capital of the city.

The bid/no-bid decision is critical to the success of construction contractors. The factors affecting the bid/no-bid decision are either qualitative or quantitative. Previous studies on modeling the bidding decision have not extensively focused on distinguishing qualitative and quantitative factors. Thus, the purpose of this paper is to improve the bidding decision in construction projects by developing tools that consider both qualitative and quantitative factors affecting the bidding decision.

This study proposes a mixed qualitative-quantitative approach to deal with both qualitative and quantitative factors. The mixed qualitative-quantitative approach is developed by combining a rule-based expert system and fuzzy-based expert system. The rule-based expert system is used to evaluate the project based on qualitative factors and the fuzzy expert system is used to evaluate the project based on the quantitative factors in order to reach the comprehensive bid/no-bid decision.

Three real bidding projects are used to investigate the applicability and functionality of the proposed mixed approach and are tested with experts of a construction company in Alberta, Canada. The results demonstrate that the mixed approach provides a more reliable, accurate and practical tool that can assist decision-makers involved in the bid/no-bid decision.

This study contributes theoretically to the body of knowledge by (1) proposing a novel approach capable of modeling all types of factors (either qualitative or quantitative) affecting the bidding decision, and (2) providing means to acquire, store and reuse expert knowledge. Practical contribution of this paper is to provide decision-makers with a comprehensive model that mimics the decision-making process and stores experts' knowledge in the form of rules. Therefore, the model reduces the administrative burden on the decision-makers, saves time and effort and reduces bias and human errors during the bidding process.

Cost overrun in infrastructure projects is a constant concern, with a need for a proper solution. The current estimation practice needs improvement to reduce cost overruns. This study aimed to find possible statistical modelling techniques that could be used to develop cost models to produce more reliable cost estimates.

A bibliographic literature review was conducted using a two-stage selection method to compile the relevant publications from Scopus. Then, Visualisation of Similarities (VOS)-Viewer was used to develop the visualisation maps for co-occurrence keyword analysis and yearly trends in research topics.

The study found seven primary techniques used as cost models in construction projects: regression analysis (RA), artificial neural network (ANN), case-based reasoning (CBR), fuzzy logic, Monte-Carlo simulation (MCS), support vector machine (SVM) and reference class forecasting (RCF). RA, ANN and CBR were the most researched techniques. Furthermore, it was observed that the model's performance could be improved by combining two or more techniques into one model.

The research was limited to the findings from the bibliometric literature review.

The findings provided an assessment of statistical techniques that the industry can adopt to improve the traditional estimation practice of infrastructure projects.

This study mapped the research carried out on cost-modelling techniques and analysed the trends. It also reviewed the performance of the models developed for infrastructure projects. The findings could be used to further research to develop more reliable cost models using statistical modelling techniques with better performance.

This paper aims to determine whether local governments (LGs) use non-consolidated municipally owned companies (MOCs), excluded from public sector entities and, consequently, from sub-national debt to avoid fiscal debt limits. This paper contributes to the literature by analysing the fiscal debt rule’s impact on the off-budget municipal activities in total and separate in different types of local government units.

This paper uses difference-in-differences and the system general method of moments model with the Blundell–Bond estimator for dynamic panel data analysis of MOCs owned by 866 Polish municipalities in 2010–2018.

This paper shows that the MOCs’ revenues support limited local public debt capacity by indebtedness restrictions imposed on municipalities in 2014. As a result, less indebted municipalities have higher off-budget revenues. The tightening of fiscal rules related to sub-sovereign indebtedness increased off-budget activities, but that effect is much stronger in rural and rural–urban municipalities than in urban municipalities and big cities.

This paper contributes to the literature by exploring the fiscal debt rule’s impact on the off-budget municipal activities in total and separate in different types of local government units. In this paper, the authors combine theories relating to private and public finance; this is a novel approach and one that is also necessary – as, in fact, the worlds of public and private actors intersect – as exemplified by the existence of MOC.

This chapter provides an overview of the social policy development and assessment in East Asia. Our study shows that social policy assessment in this region is still relying on objective indicators and interviews, even though most of the regional governments have implemented the Regulatory Impact Assessment for improving regulation quality. General approaches to measuring social value such as Cost–Benefit Analysis, Cost-Effectiveness Analysis and Social Return on Investment are not commonly used in the formulation of social policies. We compare the features of these approaches and provide suggestions about how to embed social value assessment tools into social policy and strategy development process.

This study aims to draw attention to consumers' behaviours which are changing on account of the COVID-19 pandemic, provide an understanding of the factors influencing these behaviours and emphasise their importance in building contemporary business models for the restaurant industry. The article is a case study of the Polish restaurant sector based on a comparison with the worldwide literature.

A study of the current literature on the subject pertaining to the issues discussed, an analysis of them, mainly by examining trade reports, with a special focus on the following databases (BDL GUS, CBOS, IGGP PKD) and foreign references, as well as Internet sources, using the systematic (structured) literature review (SLR) method. The authors searched the databases between May 2020 and May 2022, paying attention to the following keywords: COVID-19, consumer behaviours, food services, market segmentation, Poland.

The analysis allowed the authors to identify the most important factors influencing consumer behaviour under the influence of the COVID-19 pandemic. This in turn enabled them to verify a hypothesis concerning the significant impact of the COVID-19 pandemic on consumers’ behaviours on the food service market. Results from an analysis of trade reports and from a literature review confirm the hypothesis proposed, leading to the conclusion that the contemporary reality in Poland currently requires businesses to continuously monitor consumers’ behaviours in a turbulent and uncertain environment.

The systematic identification of changes taking place in consumers’ behaviours will make it possible to adapt a portfolio of services to changes observed in this regard.

The analysis conducted by the authors in 2021 to examine trends in consumer behaviours proved that changes affecting their thinking were undoubtedly accelerated by the pandemic of a contagious disease – COVID-19.

Some consumer trends that appear to be a response to limits and restrictions may be observed for a longer period of time. Therefore, those restaurant owners who want to successfully go through the stage of adaptation to the new reality will have to focus, in the short term, on actions designed to identify their customers’ needs and expectations anew and tailor their business models and offer accordingly.