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  • Author: Adam Wojciechowski x
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Abstract

The article presents the results of an attempt to use high-resolution X-ray micro-computed tomography (micro-CT) to model the thermal insulation of clothing as one of the most important parameters affecting the heat balance between a human and his/her surroundings. Cotton knitted fabric applied in functional clothing for newborns and aramid woven fabric used in multilayer protective clothing for firefighters were the tested materials. The 3D models of real textiles based on micro-CT images were developed. Next, the models were applied to heat transfer simulations using the finite volume method. The usefulness of the models was experimentally verified using thermography with real textiles. The simulation results were consistent with the measurement results and confirmed the relationship between the thermal insulation and geometry of the textiles on the one hand and the physical parameters of the raw materials from which they were made on the other hand.

Abstract

The article presents an analysis of the need to introduce pro-ecological solutions at the fuel sector of industry, resulting from dynamic economic development, and environment protection requirements. The forecasts on the number of vehicles in the world and the subsequent growth of interest in alternative fuels are presented. The advantages of using these fuels as compared to petroleum fuels and electricity are described. The presented analysis emphasizes the context of EU legislation on environmental requirements. At the same time, it was pointed out the need to obtain the required technical and energy characteristics of alternative fuels, the competitive costs of their production, and important environmental aspects. Taking into account these premises and the principle of circular economy closed circuit, alternative fuels from organic waste, in particular from enormous amounts of organic non-biodegradable wastes (packaging, multi-material fabric, rubber, tires) were proposed. It has been shown that thermal decomposition by thermolysis, described briefly in the article, can be a method suitable for a wide economic application within the alternative fuel production system. Based on literature data and own experience, it has been found that the quality of fuels (oil, gas) obtained from the thermal decomposition of organic and mixed waste is not different from the requirements for the best quality raw materials used in the production of petrol and may even exceed the properties of petroleum. Introduction of the system of regional production and distribution of alternative fuels from waste could be remarkable driver of small towns and rural areas revitalization and development, while supporting build up and improvement of local communities.

Abstract

Content-based image retrieval methods develop rapidly with a growing scale of image repositories. They are usually based on comparing and indexing some image features. We developed a new algorithm for finding objects in images by traversing their edges. Moreover, we describe the objects by histograms of local features and angles. We use such a description to retrieve similar images fast. We performed extensive experiments on three established image datasets proving the effectiveness of the proposed method.

Internet shopping optimization problem

A high number of Internet shops makes it difficult for a customer to review manually all the available offers and select optimal outlets for shopping. A partial solution to the problem is brought by price comparators which produce price rankings from collected offers. However, their possibilities are limited to a comparison of offers for a single product requested by the customer. The issue we investigate in this paper is a multiple-item multiple-shop optimization problem, in which total expenses of a customer to buy a given set of items should be minimized over all available offers. In this paper, the Internet Shopping Optimization Problem (ISOP) is defined in a formal way and a proof of its strong NP-hardness is provided. We also describe polynomial time algorithms for special cases of the problem.

Fieldwork results of wader research stations working in Poland in 2002-2003