An Thanh Hong Nguyen and Tuan Van Nguyen
This paper examines the relationship between working capital management and corporate profitability of Vietnamese listed firms. We propose a different interpretation of the empirical evidence that takes into account the dependency of collection and payment decisions. This helps establish the causal relationship between working capital management and firm profitability, which made the interpretation of the empirical results more meaningful and consistent with the real practice of firms. The analysis results based on a sample of 374 Vietnamese listed firms in the period from 2008 to 2014 show that working capital management positively affects the performance of Vietnamese listed companies. However, the results also indicate that Vietnamese firms do not intentionally use trade credit policy to enhance firms’ performance and the observed relationship between trade credit and profitability, though significant, is just by coincidence.
Ivana Cechova, Joanna Bartnicka and Luboslav Dulina
Musculoskeletal complaints represent a common occupational problem for health care workers throughout the world. This study provides shortened results of review by Nordic Questionnaire, which was modified for review reasons. The aim of the study is verification of work-related load Slovak and Polish nurses in their work and mutual comparison of the results. Comparison of statistical sample of Slovak nurses (468) and Polish nurses (48 for this moment) points to certain common features in the field of pain and the determination of their causes. Verification of the knowledge base of nurses in the field of ergonomics, principles of manipulation of load and kinestetika shows slightly better results for Polish nurses. The study will continue to compare larger statistical samples, identify the most common pains and their causes to the reason prevent them.
Dorota Klimecka-Tatar and Katarzyna Kapustka
The visual management technique used in process improvement, i.e. value stream mapping (VSM) has been presented in the paper. Value stream mapping is one of the basic management tools in the context of Lean Management or Lean Production. It allows to visualize the flow of decision, information, material and their connections in the full production cycle (from the order, through planning, production, to shipping to the customer). VSM is a lean tool that gives the ability to create flows in the process before implementing changes. In this paper, the possibilities of changes planning based on the current and future status maps have been discussed. On the basis of the current state map (CSM), the areas requiring improvement and operations which efficiency is decisive and for the process have been designated. Particular attention has been paid to the possibilities of using VSM in unit production processes. In the paper has been proposed the two possibilities for company development in terms of the improvement technique in line with the Kaizen philosophy as well as the implementation of process innovations. Which means balanced development through the improvement of the existing process or an acute development strategy through the implementation of process innovations (which involves significant costs).
The article describes a method for analyzing and solving problem situations with the use of Su-Field models and 76 inventive standards. These tools are part of the “Theory of Inventive Problem Solving”. The author has presented the basic concepts of Su-Field models, including in the compilation of the most commonly used substances their fields and types of interactions in Su-Field models. The inventive standards have also been presented and grouped. Attempts have been made to solve two undesirable situations that occur during the operation of a complex technical system, which is the fuel injector of the self-ignition engine. Problem situations related to insufficient impact were modelled - too low tightening of the injector spring, and negative (harmful) interaction - erosive wear of the holes in the atomizer nozzle. Using the inventive standards of Class-1 and Class-2, general solutions to these problems have been found. After the transformation, exemplary detailed ways of solving the aforementioned problems have been presented in order to improve the design of the injector for these models. A summary and comments on the applicability of the presented methodology, regarding such complex technical systems, have also been presented.
The increase of energy efficiency in autonomous marine generating sets improves the overall efficiency of the ship’s propulsion. One of the methods to increase the efficiency of generating sets is the use of synchronous machines with permanent magnets in sets as generators (PMSG). The use of PMSG in connected with the need to install power converters in order to maintain constant parameters of the supply voltage and the possibility of reactive power’s distribution between generating sets that work in parallel. The article presents the possibility of using transformer multi-level inverters in parallel operation of marine generating sets with PMSG. On the basis of the results of simulation tests, the theoretical assumptions for the possibilities of active and passive power adjustment in the parallel operation of generating sets were confirmed.
Kinga Stecuła and Mikheil Chikhradze
The article presents a proposal of use a decision table to support the decision-making process in scope of maintenance management in mining companies. In particular, it refers to decisions related to evaluation and improvement of mining machinery use in the mining production process. The article presents the theoretical foundations of decision tables building and characteristics of the most important stages of creating this table. This whole process was tried to refer specifically the mining industry. For this reason, during construction of the decision tables, the results of research on the effectiveness of the selected mining machines were used. The conducted research provided a lot of data, information and knowledge on the work of the particular mining machines, especially regarding the number and reasons for unplanned breaks during the machines’ work. The developed decision table will consist of conditions, rules and actions whose purpose is to define the recommendations for the particular groups of participants in the mining production process. The obtained results will form the basis for the development of the recommendations and proposals of actions to improve the level of use of mining machines. The authors focused mainly on the practical use of tables to support the decision-making process regarding maintenance and improvement of effectiveness of mining machines. The obtained results confirm the validity of the adopted assumptions. Decision tables can become an important tool that supports the decision-making process within mining companies.
Aneta Włodarczyk and Marta Kadłubek
Tightening the environmental norms that result from the priorities of the EU 2030 Energy and Climate Package and the reform of the EU ETS have caused the necessity to implement an effective system of managing the risk of carbon dioxide emission and integrate it with the existing enterprise management system. Evaluation of the direction and strength of correlation between EUA price changes and energy companies stock price returns is crucial from point of view the managerial staff making proper decisions about the use of the CO2 emission permits by energy companies. It is an important stage of carbon emission risk management process. The aim of this paper is to verify the possibility of use the multifactor models with GARCH structure as a tool supporting the carbon emission management process in energy companies. Empirical analysis is connected with the estimation of multifactor models with GARCH structure in the Phase II and Phase III of the EU ETS functioning for two groups of Polish energy companies: group of the Respect Index companies and others. Such an approach allows to check whether the Respect Index companies are more robust than others on the carbon emission risk, in particular the EUA price risk associated with the intensification works on modifying the EU ETS functioning. We found that the impact of EUA price changes on energy companies stock returns and their volatility is statistically insignificant in case of all Respect Index companies.
In pursuit of higher energy savings and de-carbonization, greater fuel diversity and lower pollutant emission is possible by production processes through energy-savings opportunities and associated environmentally-benign technologies. Current production processes represents the biggest consumption of energy, and the greatest amount of emissions emitted to the environment. Improvement in energy efficiency is considered as the basic principle in realizing energy-saving, bringing cost-effective benefits and reduction of greenhouse emissions. Hence, this study proposes a framework to assess alternative sustainability of cogeneration systems, integrating the economic, environmental, and social indicators. The results showed that the cogeneration system with a new boiler with a 600 PSIG pressure and a new turbine seems to be a cost-efficient solution compared to the baseline scenario saving energy at the level of 1,823,072 kWh/yr (63%) against the baseline scenario. In the case study, the implemented solution in the plant improved the overall sustainability degree of technology by 53% (from 46% as baseline to 97%).
The dynamics of demographic changes manifested in the processes of an ageing population affect Poland.In response to the situation, gerontechnology is emerging as an interdisciplinary field of scientific research in which technology is directed towards the aspirations and opportunities of the older persons. One of the examples of technologies that will be able to support the ageing population in the future are humanoids, that is, robots resembling a human being and equipped with artificial intelligence. The purpose of this article was to examine relationships between trust in the use of humanoids to care for the older people, the usefulness of technology, the ease of use, perceived threats, general trust and trust in science and technology. A survey method was used to collect data for research. The electronic questionnaire survey was disseminated among members of the Polish society. 643 filled questionnaires were received.