The objective of this work was investigation of the growth dynamics of proteolytic bacteria and the enzymatic activity in soil for the cultivation of maize (Zea mays L.), as well as the maize yield under application of some selected organic fertilizers. Intensity and the direction of the developed changes in the soil depended on the type of applied organic fertilizer, the size of its dose introduced into the soil and on the developmental phase of the grown plant (maize). On the basis of obtained results it was found that all tested organic substances stimulated the activity of proteases. Yields ofmaize as raw material for silages obtained from soil fertilized with sewage sludge were similar to those obtained after the application of pig slurry and they exceeded maize yields harvested from other ferti I ization objects.

The paper presents the results of an experiment with sugar-industry waste (molasses) as an organic carbon source for denitrification. The investigations concern the influence of untreated molasses and molasses after pretreatment (hydrolyzed molasses) and variable COD/N ratio (6.0: 5.0: 4.0) on denitrification efficiency and kinetics. Moreover, sludge production, in dependence on tested carbon source, was estimated. Al COD/N ratio 6 and 5, regardless or applied organic carbon source (untreated molasses. hydrolyzed molasses), the denitrification efficiency was over 98%,. However. from kinetic analysis it results that a kind or carbon source and COD/N ratio have an effect on denitrification rate. The highest nitrate removal rate - 9.5 mg N,0/(dm-1-h) was obtained al COD/N = 6 in the reactor with hydrolyzed molasses as a carbon source and the lowest - 5.14 mg N,0J(dm1-h) in reactor with untreated molasses at COD/N = 5.0. The lowering or COD/N ratio to 4 caused decrease otthe process efficiency to 27.6% (untreated molasses) and 44.3% (hydrolyzed molasses). Hydrolyzed molasses as a carbon source caused higher production of activated sludge. In reactors with untreated molasses Y equals 0.40 mg VSS/rng COD at COD/N ratio 6 and 0.31 111g VSS/111g COD at COD/N ratio 5. In reactors with molasses alter hydrolysis Y, were 1.35-lolcl and 1.5-lold higher, respectively. Since, the molasses hydrolysis results in rising costs of wastewater treatment and cause higher sludge production, untreated molasses seems to be a more suitable carbon source for dcniuification.

The aim of the study was to estimate the effect otthe composting process in the container technology Kneer on E. coli inactivation. The bacteria placed in the special carriers were introduced into the composted material. The elimination rate of E. coli differed depending on both the carriers· location in the biomass and the thermal conditions. The most effective hygienization, nr the material was noticed in summer - after 48 h in the middle layer, 6 days in the top layer and 10 days in the bottom layer. In spring and autumn, the bacteria survived the longest in the bottom layer - 85 and 45 days, respectively. Apart from the high temperature, the research points out the action of other factors such as competition, antagonism and antibiosis.

One of the most popular heuristics used to solve the permutation flowshop scheduling problem (PFSP) is the NEH algorithm. The reasons for the NEH popularity are its simplicity, short calculation time, and good-quality approximations of the optimal solution for a wide range of PFSP instances. Since its development, many works have been published analysing various aspects of its performance and proposing its improvements. The NEH algorithm includes, however, one unspecified and unexamined feature that is related to the order of jobs with equal values of total processing time in an initial sequence. We examined this NEH aspect using all instances from Taillard’s and VRF benchmark sets. As presented in this paper, the sorting operation has a significant impact on the results obtained by the NEH algorithm. The reason for this is primarily the input sequence of jobs, but also the sorting algorithm itself. Following this observation, we have proposed two modifications of the original NEH algorithm dealing with sequencing of jobs with equal total processing time. Unfortunately, the simple procedures used did not always give better results than the classical NEH algorithm, which means that the problem of sequencing jobs with equal total processing time needs a smart approach and this is one of the promising directions for further research.

This study is aimed at investigating the functionality of Visual Performance Management (VPM), along with determining the necessary features such a method should demonstrate to be an effective and meaningful tool for the development of Lean Management in an organisation. Based on the analysis of a case study in a large manufacturing organisation, a crosscutting assessment of such a system was made, a literature review proves the lack of such a comprehensive study. Six critical features of VPM were identified, they are very practical and giving many interesting insights into studied Lean method. The view emerged from empirical investigated shows VPM as of the wider functionality then only visual information exchange methodology. The VPM serves as cascade information exchange system and has substantial potential to support employee’s participation.

The paper considers the negative pandemic-type demand shocks in the mean-variance newsvendor problem. It extends the previous results to investigate the case when the actual additive demand may attain negative values due to high prices or considerable, negative demand shocks. The results indicate that the general optimal solution may differ to the solution corresponding exclusively to the non-negative realizations of demand.

The new industrial era, industry 4.0, leans on Cyber Physical Systems CPS. It is an emergent approach of Production System design that consists of the intimate integration between physical processes and information computation and communication systems. The CPSs redefine the decision-making process in shop floor level to reach an intelligent shop floor control. The scheduling is one of the most important shop floor control functions. In this paper, we propose a cooperative scheduling based on multi-agents modelling for Cyber Physical Production Systems. To validate this approach, we describe a use case in which we implement a scheduling module within a flexible machining cell control tool.

Since the beginning of the Fourth Industrial Revolution, enterprises have been promising the main advantages and benefits of implementing the Industry 4.0 technologies. However, the perception of new Industry 4.0 technologies may vary between different types of enterprises. The paper focuses on the main advantages of Industry 4.0 technologies for manufacturing enterprises. We analyze the difference of enterprise size and technological intensity in enterprise managers’ perception. The research was conducted based on a questionnaire survey that participated 217 enterprises from the Czech Republic. Statistical analysis showed that higher productivity and production volume are the main advantages of Industry 4.0. The present results show differences between enterprises according to their size. However, differences related to the technological complexity of enterprises have not been confirmed as an essential factor.

The consumption of various forms of primary and secondary energy is one of the main sources of greenhouse gas emissions to the atmosphere. Also, the increase in the prices of energy resources is an important factor affecting the economic profitability of running a business organization. Legal requirements in the European Union also affect the need to implement appropriate solutions aimed at increasing energy efficiency, which translates into the need of implementing Energy Management Systems, based the ISO 50001 standard, in many enterprises.. In the case study presented in the article, which is based on a company from the energy industry in Poland, the most important Energy Performance Indexes and the impact of the quality of their information on the results obtained were reviewed. In the analyzed example, the main process used only 28% of the total energy consumption in the organization. Insufficient attention to auxiliary processes led to an undercut of Energy Performance by nearly 11% in the first year of operation. It is partic-ularly important to properly collect data on auxiliary processes, which are very often omitted or treated in general in companies, and as shown may constitute a significant share in the total amount of energy consumed.

Horizontal Directional Drilling (HDD) is a very complex technology. Although the installation of pipelines by means of this technology is often successful, examples of unsuccessful projects are also known. Due to the complexity of the technology, with the interaction of multiple processes, risks related to uncertainties in these processes play important role. These risks are related to the variability of underground strata, changing natural environment, changes in economic environment, as well as limitations of the equipment, technical disruptions and human factors. This paper describes the risk evaluation results of the FMEA and a Pareto– Lorenz analysis for 14 external risk factors (8 natural or environmental risk factors as well as 6 economic risk factors) in HDD technology. In the proposed approach not only the probability of the external risk factor occurrence was considered, but also its consequences and the ability to detect faults, which were not plainly separated and taken into account in the literature so far. Such an approach has shown the relationship between occurrence, severity and detection for the analysed external failures. Moreover, 40 detection possibilities for the external risks in HDD technology were identified. The calculated risk priority numbers enabled ranking HDD external failures and identified the most critical risks for which the suggested detection options were unsatisfactory and insufficient, and therefore other types of risk response actions need to be explored.

The aim of the work was to develop a prioritizing and scheduling method to be followed in small and medium-sized companies operating under conditions of non-rhythmic and nonrepeatable production. A system in which make to stock, make to order and engineer to order (MTS, MTO and ETO) tasks are carried out concurrently, referred to as a non-homogenous system, has been considered. Particular types of tasks have different priority indicators. Processes involved in the implementation of these tasks are dependent processes, which compete for access to resources. The work is based on the assumption that the developed procedure should be a universal tool that can be easily used by planners. It should also eliminate the intuitive manner of prioritizing tasks while providing a fast and easy to calculate way of obtaining an answer, i.e. a ready plan or schedule. As orders enter the system on an ongoing basis, the created plan and schedule should enable fast analysis of the result and make it possible to implement subsequent orders appearing in the system. The investigations were based on data from the non-homogenous production system functioning at the Experimental Plant of the Łukasiewicz Research Network – Institute of Ceramics and Building Materials, Refractory Materials Division – ICIMB. The developed procedure includes the following steps: 1 – Initial estimation of resource availability, 2 – MTS tasks planning, 3 – Production system capacity analysis, 4 – ETO tasks planning, 5 – MTO orders planning, 6 – Evaluation of the obtained schedule. The scheduling procedure is supported by KbRS (Knowledge-based Rescheduling System), which has been modified in functional terms for the needs of this work assumption.

The automotive industry is a highly competitive sector. Manufacturers must effectively control highly complex production processes in order to fulfil all customer orders for customized cars on time, on budget and to the required quality. In this paper, the authors focus on improving the flow time of asynchronous automotive assembly lines by reducing the buffer time. A simulation-search heuristic procedure was developed and confirmed in a 5 workstations asynchronous assembly line installed in an automotive company. The proposed procedure identifies optimal performing buffer profiles for each storage level which guarantees lowest flow time while keeping the same throughput level. Experiments results show that our new algorithm significantly outperforms existing results, especially for large scale problems.

The purpose of servitization is to provide new business opportunities mainly to manufacturing companies. Companies strive to develop new services through utilizing servitization models, which are required to be applicable in several servitization scenarios. The main objective of this study is to propose a servitization model, known as “end-to-end servitization model” suitable for servitization purposes in companies. The model was developed based on several validated and commonly utilized service design models. Moreover, testing the validity of the model was implemented with the usability survey (usefulness, ease to use, easy of learning and satisfaction) with the Master’s level students, while they were developing new services by utilizing the proposed model. The results of this study indicate that the proposed servitization model can be utilized in different organizations to provide new services. Furthermore, the model can be concluded as useful, easy to use, easy to learn and it is at a satisfactory level based on the empirical evidence.