During implementation of construction projects, durations of activities are affected by various factors. Because of this, both during the planning phase of the project as well as the construction phase, managers try to estimate, or predict, the length of any delays that may occur. Such estimates allow for the ability to take appropriate action in terms of planning and management during the execution of construction works. This paper presents the use of the non-deterministic concept for describing the uncertainty of estimating works duration. The concept uses the theory of fuzzy sets. The author describes a method for fuzzy estimations of construction works duration based on the fact that uncertain data is an inherent factor in the conditions of construction projects. An example application of the method is presented. The author shows a fuzzy estimation for the duration of an activity, taking into consideration the distorting influence caused by malfunctioning construction equipment and delivery delays of construction materials.
For the construction company, tendering is the most popular way of acquiring contracts. The decision to participate in the tender needs to be made carefully, as it affects the condition of the company and is an important aspect in its quest for success. The bid/no bid decision making is a complex process involving a number of factors. The research carried out so far has mainly concerned the identification of the various kinds of influences on contractors’ bidding decisions. The researchers, on the basis of contractors’ opinions, created rank lists in an attempt to categorize the factors. In this paper the author employs factor analysis which belongs to basic methods of multi-dimensional data analysis. The paper’s aim is first to depict an output set of observed variables, that is bid/no bid factors, in terms of a smaller set of latent variables which cannot be directly observed and then to interpret the dependencies between them.
In these considerations, I undertake a polemic with thinking based on the assumption that the value of scientific achievements can be measured with almost mathematical accuracy and give fully reliable point indicators for them. It is not only part of those who introduce the current reform of higher education and science in Poland, but also experts who support them, as well as some representatives of science and natural sciences. This thinking was called point syndrome and expert syndrome. Although it was diagnosed as a manifestation of academic disease a few years ago, it still not only finds its supporters, but also translates into activities, which in some scholars cause astonishment, in others indignation, and still strong opposition in others.
The aim of the article is to present international economic integration as one of the mega trends that infl uence on the redefi nition of the factors of socio-economic development. The research procedure includes three stages. In the fi rst stage, the most important modern mega trends of socio-economic changes are organized in a synthetic way. In the second step, the genesis and changes of the process of international economic integration are elaborated. In the third stage, the infl uence of international economic integration on the changes of factors of socio-economic development is systematized. This study is being carried out as part of the FORSED research project (http://www.forsed.amu.edu.pl) fi nanced by the National Science Center as part of OPUS competition 10 – 2015/19/B/HS5/00012: New challenges of regional policy in shaping the socio-economic development factors of less developed regions.
This paper presents the innovative activity of enterprises as a process that is risky but necessary for the survival of a company in a competitive market, and as a way to maximize the long-term value for the owners. Risks and benefits were analysed, and the possible sources of added value in innovative projects were identified in the context of the capital market equilibrium and the budgeting of investments. Innovative projects become a source of added value for investors if the financial effects such as changes in the residual cash flow and higher growth rate outweigh the combined impact on the risk generated by two factors: increase of systematic risk and emerging specific risks.
A review is presented of the history of ‘impact factor’ since its introduction in 1955 by Eugene Garfield for assessing scientific periodicals to its present degeneration in the hands of science administrators who enforce its use to classify scientists. Arguments are presented against that procedure. Recently there has been an increase of resistance among scientists and the editors of periodicals who call for replacing bibliometric parameters by peer review assessment of publications.
The results of the application and evaluation of the r.sun model for calculation of the total solar radiation for the Wedel Jarlsberg Land (SW Spitsbergen) are presented. Linke Turbidity Factor (LTF), which is the obligatory parameter for direct and diffused radiation calculations with the r.sun model, is derived here with the empirical formula and meteoro− logical measurements. Few different approaches for calculation of LTF are presented and tested. The r.sun model results, calculated with these various LTF, are evaluated through comparison with total solar radiation measurements gathered at Polish Polar Station. The r.sun model is found to be in good agreement with the measurements for clear sky condi− tions, with the explained variance (R2) close to 0.9. Overall, the model slightly underesti− mates the measured total radiation. Reasonable results were calculated for the cloudiness condition up to 2 octas, and for these r.sun model can be considered as a reliable and flexible tool providing spatial data on solar radiation for the study area.
The aim of the study was to evaluate the combined effect of noise exposure and additional risk factors on permanent hearing threshold shift. Three additional risk factors were: exposure to organic solvents, smoking and elevated blood pressure. The data on exposure and health status of employees were collected in 24 factories. The study group comprised of 3741 noise male exposed workers of: mean age 39±8 years, mean tenure 16±7 years and LEX,8h = 86 ± 5 dB. For each subject, hearing level was measured with pure tone audiometry, blood pressure and noise exposure were assessed from the records of local occupational health care and obligatory noise measurements performed by employers. Smoking and solvent exposure were assessed with questionnaire. The study group was divided into subgroups with respect to the considered risk factors. In the analysis, the distribution of hearing level of each subgroup was compared to the predicted one which the standard calculation method described in ISO 1999:1990. For each of the considered risk factors, the difference between measured and calculated hearing level distribution was used to establish, by the least square method, a noise dose related correction square function for the standard method. The considered risk factors: solvent exposure, smoking and elevated blood pressure combined with noise exposure, may increase degree of hearing loss.
In order to prepare a coal company for the development of future events, it is important to predict how can evolve the key environmental factors. This article presents the most important factors influencing the hard coal demand in Poland. They have been used as explanatory variables during the creation of a mathematical model of coal sales. In order to build the coal sales forecast, the authors used the ARMAX model. Its validation was performed based on such accuracy measures as: RMSE, MAPE and Theil’s index. The conducted studies have allowed the statistically significant factors out of all factors taken into account to be identified. They also enabled the creation of the forecast of coal sales volume in Poland in the coming years. To maintain the predictability of the forecast, the mining company should continually control the macro environment. The proper demand forecast allows for the flexible and dynamic adjustment of production or stock levels to market changes. It also makes it possible to adapt the product range to the customer’s requirements and expectations, which, in turn, translates into increased sales, the release of funds, reduced operating costs and increased financial liquidity of the coal company. Creating a forecast is the first step in planning a hard coal mining strategy. Knowing the future needs, we are able to plan the necessary level of production factors in advance. The right strategy, tailored to the environment, will allow the company to eliminate unnecessary costs and to optimize employment. It will also help the company to fully use machines and equipment and production capacity. Thanks to these efforts, the company will be able to reduce production costs and increase operating profit, thus survive in a turbulent environment.
The multidisciplinary journal Polish Polar Research is bibliometrically analysed as a medium of international scientific communication in light of current citation data from SCI Ex 1996 -2002. Despite its world-wide distribution and distinctive visibility in the polar society, the journal 's two-years impact factor is invariably not very high (below 0.35) because the cited papers are mostly from the 1980s. The increasing participation of foreign (co)authors in the Polish quarterly, paired with the slowly growing number of citing articles in SCI Ex are already promising steps to the immediate information transfer and subsequently improved brief-term journal impact. Citation links with polar investigators from Germany,and also from Great Britain, Spain and the USA are clearly manifested, especially in fields of marine Antarctic ecology and biology. Even if Polish Polar Research may successfully compete with several low-rated journals from different countries indexed in SCI Ex in related categories, its continuing internationalization is urgently required.
In this paper, the recent ice regime variations in the Kara Sea have been described and quantified based on the high-resolution remote sensing database from 2003 to 2017. In general, the Kara Sea is fully covered with thicker sea ice in winter, but sea ice cover is continuously declining during the summer. The year 2003 was the year with the most severe ice conditions, while 2012 and 2016 were the least severe. The extensive sea ice begins to break up before May and becomes completely frozen at the end of December again. The duration of ice melting is approximately twice than that of the freezing. Since 2007, the minimum ice coverage has always been below 5%, resulting in wide open-waters in summer. Furthermore, the relevant local driving factors of external atmospheric forcing on ice conditions have been quantitatively calculated and analyzed. Winter accumulated surface air temperature has been playing a primary role on the ice concentration and thickness condition in winter and determining ice coverage index in the following melt-freeze stage. Correlation coefficients between winter accumulated temperature and ice thickness anomaly index, the ice coverage anomaly index, duration of melt-freeze stage can approach -0.72, -0.83 and 0.80, respectively. In summer, meridional winds contribute closely to summer ice coverage anomaly index, with correlation coefficient exceeding 0.80 since 2007 and 0.90 since 2010.
The subject of the study are strategies for the development of 9 cities, which are among the strongest centres outside the current capitals of regions (in Polish: voivodeships) in the least-developed Polish regions. These cities can give the chance to activate their surroundings. Good strategies that increase the competitiveness of cities and stimulate development can contribute to this. The aim of the research was to fi nd answers to the questions whether and to what extent the studied strategies: (1) are in line with the definition and methodology of strategic planning; (2) recognize and use specific combinations of developmental factors; (3) can contribute to the development of their surroundings. The research method involved the analysis of the strategic plans in the light of the above questions. The strategies studied are not fully in line with the strategy defi nition. They contain errors and methodological flaws commonly encountered in other strategies. They use the specificity of developmental factors, but without conscious, methodical recognition of their combinations and without exposing them. The author signals methodical problems specific to the strategic planning in territorial units and makes suggestions for planning practice.
The subject of research was urban and urban-rural communes in the peripheral areas of voivodships, that is outside the functional areas of their capitals and outside the Silesian agglomerations. The aim of the research was to: (1) recognize the most economically developed entities in the studied areas, (2) recognize how development factors and their combinations that can create territorial capital are perceived and used in municipal strategies. The methods included: (1) analysis of indicators (2) analysis of texts of 10 strategies of entities with a high level of development. It was found, that there was deficiency of specific factors of development and recognition of their combination as well as the lack of using them to create a competitive advantage.
In the article problems related to human labor and factors affecting the increasing use of industrial robots are discussed. Since human factors affect the production processes stability, robots are preferred to apply. The application of robots is characterized by higher performance and reliability comparing to human labor. The problem is how to determine the real difference in work efficiency between human operator and robot. The aim of the study is to develop a method that allows clearly definition of productivity growth associated with the replacement of human labor by industrial robots. Another aim of the paper is how to model robotized and manual operated workstation in a computer simulation software. Analysis of the productivity and reliability of the hydraulic press workstation operated by the human operator or an industrial robot, are presented. Simulation models have been developed taking into account the availability and reliability of the machine, operator and robot. We apply OEE (Overall Equipment Effectiveness) indicator to present how availability and reliability parameters influence over performance of the workstation, in the longer time. Simplified financial analysis is presented considering different labor costs in EU countries.
Introduction: Clostridium difficile (C. difficile) is a Gram-positive, anaerobic rod-shaped bacteria, widely spread in the human environment. In the last decade, the frequency and severity of Clostridium difficile infection (CDI) have been increasing, making this particular disease one of the most significant nosocomial infections. The aim of our study was an analysis of CDI risk factors, its course and consequences. Materials and Methods: Medical documentation of the patients treated for CDI in the University Hospital in Cracow and St Anne’s Hospital in Miechów has been analysed. The analysis focused on epidemiological data, blood parameters, comorbidities, recurrence rate, and complication rate (deaths included). As part of risk factors analysis, antibiotic use or hospitalisation in a period of 3 months before the episode of infection was considered relevant. Blood tests have been performed using routinely employed, standard methods. Results: We evaluated data of 168 people infected with C. difficile, out of which there were 102 women (61%) and 66 men (39%). Th e median age of the patients was 74 years for the entire population with 76 years for women and 71 years for male patients. One hundred thirteen people (67%) had been previously hospitalised, and 5 person was a pensioner of a nursing home. 99 people (59%) were treated with antibiotics within 3 months before the first episode of infection. An average length of the hospital stay because of CDI was 11 days. One hundred thirty persons (77%) experienced only 1 episode whereas 38 people (23%) had more than 1 episode of infection. The person with the largest number of recurrences had 9 of them. Conclusions: The development of CDI is an increasing problem in a group of hospitalised persons, particularly of an old age. The general use of beta-lactam antibiotics is the cause of a larger number of infections with C. diffi cile. Vast majority of patients have had at least one typical risk factor of CDI development.
This chapter provides a quantitative analysis to identify weak regions that have changed the innovation model. The analysis was carried out at the beginning of the project, in 2015, when only data on GDP per capita for the EU regions was available until 2011. It was designed to identify regions that have changed the innovation model for their in-depth qualitative research, that is to prepare case studies. To indicate the development paths of European regions, a comparative analysis of means was prepared. Innovation models and their change were indicated by clusters analysis. In addition, an econometric analysis of growth factors in the EU regions covering data on GDP per capita in the EU regions in 2014 was carried out in 2017.
The aim of this research was to assess the content and composition of the pollutants emitted by domestic central heating boilers equipped with an automatic underfeed fuel delivery system for the combustion chamber. The comparative research was conducted. It concerned fuel properties, flue gas parameters, contents of dust (fl y ash) and gaseous substances polluting the air in the flue gases emitted from a domestic CH boiler burning bituminous coal, pellets from coniferous wood, cereal straw, miscanthus, and sunflower husks, coniferous tree bark, and oats and barley grain. The emission factors for dust and gaseous air pollutants were established as they are helpful to assess the contribution of such boilers in the atmospheric air pollution. When assessing the researched boiler, it was found out that despite the development in design and construction, flue gases contained fly ash with a significant EC content, which affected the air quality.
The accumulation and translocation of trace metals in soil and in sugarcane crop irrigated with treated effluents from sugar industry compared to soil and sugarcane crop irrigated with bore-well water were determined. In the present study the impact of irrigation with treated effluent from the sugar industry on the trace metal contamination of sugarcane juice was assessed. It revealed that the mean concentrations of Cd, Pb, Cu, Mn and Zn in the soil of fields irrigated with effluent and in juice from sugarcane grown on such fields were higher than those from bore-well water irrigated fields. The concentrations of trace metals in treated effluent exceeded the permissible limits of the Indian standards (Central Pollution Control Board-2000). The concentrations of Cd, Pb, Cu and Zn in juice of sugarcane grown on fields irrigated with effluent also exceeded the permissible limits of Indian standards and WHO/FAO expert committee recommendations. Their concentrations in juice of sugarcane grown in fields irrigated with bore-well water were within the limits of safety, except for Cd. The transfer factor for Zn was considerably higher than those of the other trace metals. The metal concentrations of sugarcane juice showed significant correlations with those of soil, which was not the case when bore well water was used for irrigation.
Root associated bacteria were isolated from Suaeda nudiflora and two isolates were selected for this study: rhizospheric Bacillus megaterium and endophytic Pseudomonas aeruginosa. These isolates were inoculated into maize variety Narmada Moti during its germination. TTC (2, 3, 5-triphenyl tetrazolium chloride) staining was used to confirm the association of the isolates with the maize root. The effects of these root associated bacteria were tested alone and in combinations for cell wall reinforcement and the induction of defense enzymes such as phenylalanine ammonia lyase (PAL) and β-1,3-glucanase in the presence of fungal pathogen Aspergillus niger in maize. The results indicated that the rhizospheric bacteria had a greater fight response to fungal infection than the endophhytic bacteria due to cell wall lignification as well as the rapid induction of higher concentrations of defense related enzymes.