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Number of results: 11
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Abstract

Most often sewage treatment and sludge disposal are handled as two separate technological parts of treatment plants. Attempts are made to change the practice. Keeping the standards of treated sewage is the primary objective, and sewage sludge is a by-product which has to he get rid of. The environmental consequences of various procedures of sludge disposal are rarely considered. On the other hand, incorporation of sludge handling procedures in the processes of sewage treatment can result in cost savings and be environmentally friendly. In the presented paper, suggestions arc given on possibilities of closer integration of sewage and sludge treatment, based on experiments. Research aimed at sewage sludge quantity minimization and quality upgrading, recovery of phosphorous and efficient nitrogen removal. Appearing occasionally scum floating over biological sewage treatment units was shown to be considered as an integrated part or sewage treatment and sludge handling at EBNRP's.
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Authors and Affiliations

Jan Suschka
Eligiusz Kowalski
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Abstract

This paper presents an experimental study on Cochineal Red A dye adsorptive removal by yeast. Batch equilibrium and kinetic tests were conducted in constant temperature of 30 ◦C for the dye’s initial concentration range of 0.02–0.50 g/L (pH = 3 and 10) and 0.02–0.35 g/L (pH = 7:6). The equilibrium was reached after 105–120 min. Yeast demonstrated the adsorption capacity of 10.16 mg/g for acidic environment (pH = 3) and slightly lower values (8.13 mg/g and 8.38 mg/g respectively) for neutral (pH = 7:6) and alkaline environment (pH = 10). The experimental equilibrium results were fitted with Langmuir, Freundlich, Sips and Toth isotherm models. Most of them (Freundlich model being the exception) were proven sufficient for the experimental data correlation. The adsorption kinetic studies showed that the pseudo-second order model fits better the experimental data than the pseudo-first- order model. Results achieved from intra-particle diffusion model indicate that powdered yeast are a nonporous adsorbent. The percentage of solution discoloration reached a maximum value of 75% at pH = 3 for an initial dye concentration of 0.02 g/L.

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Authors and Affiliations

Martyna Borysiak
Elżbieta Gabruś
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Abstract

The paper presents comparative analysis of the results of low- cycle fatigue experiments on specimens made of 45 steel under uniaxial loading and bending. The analysis involves, among other things, the cyclic properties and the fatigue life of the specimens in a wide range of loading conditions. The experimental techniques used during bending enabled us to estimate the influence of strain distribution on fatigue life. The materials data obtained under the loading conditions mentioned above were employed to estimate the fatigue life of the structural elements. The results of experiments and calculations are presented in the form of fatigue curves. They also show the influence of axial loading and bending on the accuracy of the calculations.
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Authors and Affiliations

Stanisław Mroziński
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Abstract

The rapid development of digital technologies have created unprecedented opportunities for the industrial world. Enterprises, especially small and medium sized companies, struggle to successfully implement these technologies, and there is scant literature to support this endeavor. The authors hypothesize that ERP (Enterprise Resource Management) implementation, being a mature field, can guide digital technology implementation, taking into considerations the similarities. A systematic literature review was conducted to determine the critical success factors (CSF) of ERP implementation in SMEs that were used to derive guidelines for digital technology implementation case study. The results of the case study is another list of CSF that more correctly mirror the digital technology implementation needs. They are: “digitalization strategic plan”; “project sponsor/leader”; “commitment to the workplace”; “involvement of top management”; “reasonable project scope”; “compatibility with existing processes/systems”; “progressing with small steps”; “use of correct competencies”; and “involving the users”.
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Authors and Affiliations

Dan Palade
1
ORCID: ORCID
Charles Møller
1
ORCID: ORCID

  1. Materials and Production, Aalborg University, Denmark
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Abstract

This study was carried out to evaluate the effect of steel slag (SS) as a by-product as an additive on the geotechnical properties of expansive soil. A series of laboratory tests were conducted on natural and stabilized soils. Steel slag (SS) was added at a rate of 0, 5, 10, 15, 20, and 25% to the soil. The conducted tests are consistency limits, specific gravity, grain size analysis, modified Proctor compaction, free swell, unconfined compression strength, and California Bearing Ratio. The Atterberg limit test result shows that the liquid limit decreases from 90.8 to 65.2%, the plastic limit decreases from 60.3 to 42.5%, and the plasticity index decreases from 30.5 to 22.7% as the steel slag of 25% was added to expansive soil. With 25% steel slag content, specific gravity increases from 2.67 to 3.05. The free swell value decreased from 104.6 to 58.2%. From the Standard Proctor compaction test, maximum dry density increases from 1.504 to 1.69 g/cm3 and optimum moisture content decreases from 19.77 to 12.01 %. Unconfined compressive strength tests reveal that the addition of steel slag of 25% to expansive soil increases the unconfined compressive strength of the soil from 94.3 to 260.6 kPa. The California Bearing Ratio test also shows that the addition of steel slag by 25% increases the California Bearing ratio value from 3.64 to 6.82%. Hence, steel slag was found to be successfully improving the geotechnical properties of expansive soil.
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Authors and Affiliations

Worku Firomsa Kabeta
1 2
ORCID: ORCID

  1. Gdansk University of Technology, Faculty of Civil and Environmental Engineering, Gabriela Narutowicza 11/12, 80-233, Gdansk, Poland
  2. Jimma University, Faculty of Civil and Environmental Engineering, Jimma saris, 378, Jimma, Ethiopia
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Abstract

The article presents the concept of intelligent city. Cities are unquestionably central to many topics in economics and regional science: the business location, the driving forces for business, the economic growth factors, externalities and amenities, knowledge spillovers and knowledge hubs. But what, exactly, is city in this context. This paper argues that today city should be seen more as an intelligent economic system allowing the utilisation of economic and public value than a technology- rich and smartly managed place. Thinking about cities through this particular lens allows insights from a variety of fields – including public services analysis in urban economics, regional science studies and business studies in economic geography – to be applied. This opens new approaches to issues such as institutional and territorial origins of governance processes.

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Authors and Affiliations

Artur Ochojski
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Abstract

The article presents a method for 3D point cloud segmentation. The point cloud comes from a FARO LS scanner – the device creates a dense point cloud, where 3D points are organized in the 2D table. The input data set consists of millions of 3D points – it makes widely known RANSAC algorithms unusable. We add some modifi cations to use RANSAC for such big data sets.

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Authors and Affiliations

Leszek Luchowski
Przemysław Kowalski
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Abstract

Technical and operational energy efficiency measures for ships, such as the energy efficiency design index (EEDI) and ship energy efficiency management plan (SEEMP), aim to improve the energy efficiency of international shipping. Studies show that absolute emissions from international shipping will increase despite their mandatory application. For this reason, it is important to assess the impact on the effectiveness of the application of mandatory efficiency measures on future emissions. Further measures are being developed at the International Maritime Organization to control emissions from ships, in particular greenhouse gases (GHG) that contribute to climate change. In January 2019, a system of collecting fuel consumption data by ships (Ship Fuel Oil Consumption Database) was introduced.

Energy efficiency measures promoted by the IMO Maritime Environment Protection Committee, initially as facultative, then as mandatory, show strong preventive character. The mandatory use of energy efficiency measures by ships as well as the development of energy efficiency management policies by shipping companies contributes to climate protection and adaptation to climate change.

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Authors and Affiliations

Dorota Pyć
ORCID: ORCID
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Abstract

The purpose of this article is to establish a frame for arranging and classifying observations relating to the indigenous knowledge and oral traditions of the San people of southern Africa, mainly in Namibia. Oral literature of the San people serve, therefore, as a valuable source for re-constructing and reinforcing a positive collective identity of their history and cultural diversity. Several forms of expression such as folklore, poems, plants' names and personal narratives will be provided.

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Authors and Affiliations

Patrycja Kozieł
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Abstract

The Author presents several methodological aspects referring to photographs as historical sources. In this article it is viewed as an iconographic source. The problem of photographs as iconographic sources is discussed in the context of historical semantics and theory of historical presence.
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Authors and Affiliations

Agata Barzycka
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Abstract

In the Moorish Hall of Kórnik Castle there is a group of 12 stucco coats of arms, situated according to the programme developed by Tytus Działyński, owner of the residence. Another 34 coats of arms painted on canvas were meant to be put on the northern wall of the hall. This article contains a new, much improved in comparison to the previous ones, description of the whole set, as well as an attempt to reconstruct the process of its creation and analyze the ideas standing behind its design. Thanks to the research it was possible to identify the graphics used as models by Działyński, describe the various stages of his work, point out what was never finished and above all to propose a new and in-depth interpretation of the ideological message embedded in the whole set. It seems that Działyński intended to depict the history of Poland in its golden age by the use of the coats of arms. Those 34 missing coats of arms of the voivodeships of the Polish-Lithuanian Commonwealth were meant to be the most important of all and their absence makes it impossible to understand Działyński’s intentions.

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Authors and Affiliations

Aleksandra Losik-Sidorska

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