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Keeping Higher Education Aligned with the Requirements and Expectations of the Knowledge-Based Economy

Abstract

Paper describes the procedure for developing academic programs which are properly aligned to the requirements of the knowledge-based economy. The paper also addresses the continuous quality improvement (CQI) process with the CQI loop closing on the program level and the course level. This process is needed to make continuous adjustments to an academic program, so that the program is always aligned to the constantly-changing needs of the economy. Paper also discusses the system of mutual dependency between the academic program and external partnership like local industry, secondary schools, local government, local community, regional business incubator center, other educational institutions, alumni and industrial advisory council. The ongoing collaboration with external partners allows the program to prosper and grow.

Open access
LEAN Production issues in the organization of the company - the first stage

Abstract

Today’s market determinants and most importantly, very dynamically changing customer requirements significantly shortened the product life cycle. This situation reflects in companies by common extension of the assortment offered and personalised serial production. The result of a flexible approach to market changes is the implementation of LEAN concept, which, both in terms of management and production aims to develop efficiency within an organisation, which will then enable quick and dynamic response to changes in the environment. The popularity of LEAN concept (in management and production) among managers comes from its universality and a wide range of instruments used to maximise the use of existing potential. The main assumptions of LEAN concept are aimed at the maximum use of an organisation’s resources, defining the activities necessary to execute an order and identifying the areas generating losses and then minimising them and eventually eliminating. LEAN concept is based on flagship-main tools for identification and modernisation of processes, the difficulty in using them results from the need to recognise and select the most effective ones that meet the expectations of a given organisation. The article presents issues related to the first stage of implementing LEAN concept in a company’s structures, i.e. identification of opportunities and selection of appropriate tools.

Open access
Level and Structure of Inputs in Specialist Farms

Abstract

The objective of the paper is to determine the size of human and objectified labour in selected specialist vegetable farms. The paper covered studies carried out in the area of southern Poland in 50 organic vegetable farms. Based on the detailed studies, the size and structure of work, and energy inputs used in the production process were determined. The highest inputs of labour per a unit of the production area and 1 tonne of a product were incurred in production of Cucurbita vegetables – 1883.1 and 547.74 man-hour, while the lowest of Solanacea vegetables – 342.8 and 7.11 man-hour. From among all analysed groups of plants, the highest energy inputs were incurred in cultivation of root and onion vegetables and they were three times higher than in traditional farms. Contrary, the lowest inputs were incurred in cultivation of brassica and Solanaceae vegetables.

Open access
Modal Competition and Complementarity: Cost Optimization at End-User Level

Abstract

The paper aims to identify possible methods for balancing the allocation of transport flow on modal subsystems in order to efficiently use the infrastructures and reduce the negative effects of today’s unbalance. The aspects of intermodal competition are reviewed, considering the economic concepts regarding the substitutability of transportation services, conformation degree to the perfect competition model and the nature of cross elasticity demand.

A top-down analysis over the whole infrastructure assembly is performed. The results, under the presumption of valid work hypothesis, indicated that for further analysis the set of networks transferring material flows can be assumed as disconnected from the other networks sets transferring energy, informational and values flows.

The second part of the paper develops, for that disconnected networks, a generalized cost optimization model for multimodal transportation, where the comfort and safety are accounted. Thus, the performance of the existing algorithms based only on trip length, trip duration and energy consumption can be significantly improved. Additionally, the author proposes three new independent types of modal analysis that allow end-users and companies involved in transport organization to optimize their modal choice and the whole transport process organization.

Open access
Numerical and experimental analyses of non-energy absorbing lighting poles

Abstract

Apart from the strength requirements, modern lighting pole designs have to meet a number of safety requirements in the event of collisions. The paper compares the experimental tests performed at the collision test track according to EN 12767 with the results of the numerical analysis carried out in Ansys LS-DYNA. The objective of the work is to prepare a new structure of a thin-walled lighting pole of steel which minimizes absorption of the kinetic energy of the vehicle and, simultaneously, its production costs are comparable to those of a standard pole. The tests were carried out at an impact speed of 100 km/h.

Open access
Performance Evaluation of African Breadfruit (Treculia Africana) Seed Dehuller

Abstract

This paper reports the effect of the parboiling time on dehulled kernel out-turns (DKO) of African breadfruit seeds, and the most recent effort to upgrade an existing dehuller and its performance. Two common and readily available varieties – Treculia var. africana and var. inverse were used in the study. The seeds were parboiled for 0 (control), 2, 5, 8, 11 and 14 minutes and then dehulled. The result revealed that the parboiling time had a significant effect on the DKO of the two varieties of the seed. The DKO increased from 0 to 5 min of the treatment, after which it decreased considerably up to 14 min of the parboiling time. The obtained data were used to develop a non-linear quadratic regression model to predict the DKO as a function of the parboiling time. The performance evaluation of the breadfruit seeds dehuller revealed that it was significantly influenced by the variety.

Open access
Preliminary Studies to Use Textile Fibers Obtained from Recycled Tires to Reinforce Asphalt Mixtures

Abstract

The use of crumb rubber in the modification of asphalt has occurred because of the problems related to disposal of scrap tires. However, the use of scrap tires in asphalt pavements, known as asphalt rubber pavements, can minimize environmental impacts and maximize conservation of natural resources. The textile fibers from recycled tires are typically disposed of in landfills or used in energetic valorization, but similar to other fibers, they can be used as a valuable resource in the reinforcement of engineering materials such as asphalt mixtures. Thus, this work aims at studying the use of textile fibers recycled from ground tires in the reinforcement of conventional asphalt mixtures. The application of textile fibers from ground tires was evaluated through laboratory tests on specimens extracted from slabs produced in the laboratory. Indirect tensile tests were performed on a series of nine asphalt mixtures with different fiber and asphalt contents and compared with a conventional mixture. The results obtained from a 50/70 pen asphalt were used to define three asphalt mixture configurations to be used with 35/50 pen asphalt. The results indicate that the textile fibers recycled from used tires can be a valuable resource in the reinforcement of asphalt mixtures.

Open access
Problems of Polish enterprises in the field of innovation

Abstract

Innovative activity of enterprises in Poland is mostly generated by European funds that concern boosting European regions based on its significant resources and new technologies. Polish enterprises development within innovations is based mainly on accumulating new products and new technologies that improve organization and increase sale of products and services. Papers presents research findings that concern problems resulting from the innovations implementing in Polish enterprises comparing with European results. There is presented European Innovation Index providing a comparative assessment of the innovation performance at the country level of the EU Member States and the Regional Innovation Scoreboard (RIS) that presents results of innovative activity in Polish and European enterprises including regional data from the Community Innovation Survey (CIS).

Open access
Propulsion System Modelling for Multi-Satellite Missions Performed by Nanosatellites

Abstract

Progress in miniaturization of satellite components allows complex missions to be performed by small spacecraft. Growing interest in the small satellite sector has led to development of standards such as CubeSat, contributing to lower costs of satellite development and increasing their service competitiveness. Small satellites are seen now as a prospective replacement for conventional sized satellites in the future, providing also services for demanding users. New paradigms of multi-satellite missions such as fractionation and federalization also open up new prospects for applications of small platforms.

To perform a comprehensive simulation and analysis of future nanosatellite missions, an adequate propulsion system model must be used. Such model should account for propulsion solutions which can be implemented on nanosatellites and used in multi-satellite missions.

In the paper, concepts of distributed satellite systems (constellations, formations, fractionated and federated) are described with a survey of past, on-going and planned multi-satellite nanosatellites missions. Currently developed propulsion systems are discussed and the models of propulsion systems embedded in the WUT satellite simulation model are presented.

Open access
Prospects for Production and Consumption of Second Generation Biofuels in Ukraine

Abstract

The article analyzes the current state of production of second generation biofuels in the world and evaluates the possibility of launching such production in Ukraine. The work is topical due to the fact that liquid biofuels can replace a certain share of motor fuels consumed in Ukraine, thus contributing to the strengthening of the country’s energy independence. The purpose of the study is to assess feasibility of a project on the production of second generation bioethanol in Ukraine; the task is to carry out a preliminary feasibility study for such a project. The analysis of the study of pure co-substrate fermentation and as a supplement for cattle manure proves that the maximum biogas yield obtained using alcohol stillage in a ratio of 40-80% increased compared to fermentation of pure cattle manure. The use of pure bards compared to the bard and the slurry mixture increases the maximum yield of biogas. It was found that the biogas obtained from the use of alcohol stillage is a high con-sumption of biogas with the methane content of between 70 and 78%.

Open access