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Number of results: 14
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Abstract

W artykule opisano spory wokół sposobów zbierania danych na temat smogu w Polsce. Ramą teoretyczną analizy są studia nad nauką i technologią, a w szczególności badania nad rolą infrastruktur, standardów i danych. W części opisowej przedstawiono rolę infrastruktury pomiarowej w kształtowaniu relacji pomiędzy różnymi podmiotami zajmujący się pomiarem jakości powietrza, a następnie zanalizowano dwa wymiary konfliktu. Pierwszy z nich dotyczy kwestii metodologicznych i związany jest z rzetelnością pomiaru. Drugi natomiast – ontologii smogu, to znaczy odmiennego ujmowania problemu zanieczyszczenia przez ekspertów i obywateli, co ma przełożenie na praktyki społeczne.

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Authors and Affiliations

Michał Wróblewski
Wojciech Goszczyński
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Abstract

The aim of this study is to find the cost design of RC tension with varying conditions using the Artificial Neural Network. Design constraints were used to cover all reliable design parameters, such as limiting cross sectional dimensions and; their reinforcement ratio and even the beahviour of optimally designed sections. The design of the RC tension members were made using Indian and European standard specifications which were discussed. The designed tension members according to both codes satisfy the strength and serviceability criteria. While no literature is available on the optimal design of RC tension members, the cross-sectional dimensions of the tension membersfor different grades of concrete and steel, and area of formwork are considered as the variables in the present optimum design model. A design example is explained and the results are presented. It is concluded that the proposed optimum design model yields rational, reliable, and practical designs.

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Authors and Affiliations

N. Karthiga Shenbagam
N. Arunachalam
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Abstract

For a very long period of time, Polish waste management was based mainly on landfilling at landfills, which had a negative impact on the surrounding environment. The EU requirements for the Member States have led to a revolution in Polish legislation on waste management and local governments have become responsible for creating local waste management systems that will affect the achievement of EU targets. One of the solutions undertaken by several municipalities is the construction and operation of a municipal waste thermal treatment installation, which not only reduced the amount of waste deposited, but also supported the local power industry by generating electricity and heat. The emission standards for installations producing energy from waste, as in the case of conventional power plants and combined heat and power plants, are very strict, therefore, the continuous monitoring of emitted pollutants is carried out, and waste gas treatment systems are developed based on the best available techniques (BAT). The article presents emission standards applicable to waste incineration plants, including duties in the field of the environment, as well as issues related to the installation as a source of energy. In addition, the currently functioning waste incineration plants in Poland have been briefly characterized, and development plans in this area in the country have been described.

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Authors and Affiliations

Jagoda Gołek-Schild
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Abstract

Longitudinal and shear ultrasonic wave velocities were measured versus temperature in the viscosity standards of Paragon S8000S, N30000S and Cannon N2700000. The measurements were performed by the through-transmission method at the frequency of 2 MHz. Ultrasonic pulses were sent via polymethyl methacrylate (PMMA) waveguides between the tips of which a small amount of the particular standard liquid was placed. The velocities of longitudinal and shear waves were determined to depend on the viscosity of the liquid and increase with the viscosity.
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Authors and Affiliations

Rymantas Kazys
Algirdas Voleisis
Reimondas Sliteris
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Abstract

In the text the author makes a critical assessment of legal solutions regulating the education of teachers in Poland. In the realms of argument, he refers to his own experiences as a member of the Polish Accreditation Committee. The presentation of those experiences reveals areas of omissions, irregularities, and even pathologies in the process of conferring teaching qualifications on graduates of schools of higher education. The author derives the sources of the status quo from imperfections or contradictions in the documents regulating the same areas of education, as well as from the struggle of schools of higher education to survive in the market, leading to a dramatic reduction in the quality of education. The text ends in demands for necessary modifications of the standards of teacher education and changes in legislation.

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Authors and Affiliations

Amadeusz Krause
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Abstract

Obligation to use the best available technology (BAT) in the protection of the environment is envisaged in many international treaties. It is not only legal, but also moral obligation. Treaties concluded under the auspices of the International Maritime Organization (IMO) that aim at the protection of the environment and the prevention of pollution from ships, enshrine the precautionary principle which encompasses the obligation to use the best available technology. Many IMO treaties consider technological development, some of them even drive it, however, not all standards are based on the best and the newest solutions. The discussion at the IMO’s Marine Environment Protection Committee regarding the energy efficiency design index demonstrates the impact of political and economic interests on the text of adopted standards. The Initial IMO strategy on the reduction of greenhouse gas emissions from ships identifies levels of ambitions consistent with the Paris Agreement. In the shipping industry this will be achieved, if the adopted standards were based on the best available technology.
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Authors and Affiliations

Dorota Lost-Siemińska
1
ORCID: ORCID

  1. zastępca dyrektora departamentu prawnego i stosunków zewnętrznych, szefowa biura prawnego, Międzynarodowa Organizacja Morska
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Abstract

Stepped spillway is hydraulic structure designed to dissipate the excess in kinetic energy at the downstream of dams and can reduce the size of stilling basin at the toe of the spillway or chute. The flow on a stepped spillway is characterisedby the large aeration that can prevent or reduce the cavitation damage. The air entrainment starts where the boundary layer attains the free surface of flow; this point is called “point of inception”. Within this work the inception point is determined by using software Ansys Fluent where the volume of fluid (VOF) model is used as a tool to track the free surface thereby the turbulence closure is derived in the k – ε turbulence standard model. This research aims to find new formulas for de-scribe the variation of water depth at step edge and the positions of the inception point, at the same time the contour map ofvelocity, turbulent kinetic energy and strain rate are presented. The found numerical results agree well with experimental results like the values of computed and measured water depth at the inception point and the numerical and experimental inception point locations. Also, the dimensionless water depth profile obtained by numerical method agrees well with that of measurement. This study confirmed that the Ansys Fluent is a robust software for simulating air entrainment and explor-ing more characteristics of flow over stepped spillways.

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Authors and Affiliations

Chakib Bentalha
Mohammed Habi
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Abstract

In the paper an application of differential evolution algorithm to design digital filters with non-standard amplitude characteristics is presented. Three filters with characteristics: linearly growing, linearly falling, and non-linearly growing are designed with the use of the proposed method. The digital filters obtained using this method are stable, and their amplitude characteristics fulfill all design assumptions.

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Authors and Affiliations

A. Słowik
M. Białko
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Abstract

Hard turning is a machining process that is widely used in the precision mechanical industry. The characterization of the functional surface texture by the ISO 13565 standard holds a key role in automotive mechanics. Until now, the impact of cutting conditions during hard turning operation on the bearing area curve parameters has not been studied (ISO 13565). The three parameters Rpk , Rk and Rvk illustrate the ability of the surface texture to resist friction. In this work, the main objective is to study the impact of cutting conditions (Vc, f and ap) of the hard turning on three parameters of the bearing area curve. The statistical study based on response surface methodology (RSM), analysis of variance (ANOVA) and quadratic regression were performed to model the three output parameters and optimize the input parameters. The experimental design used in this study is the Taguchi L25 orthogonal array. The results obtained show that the cutting speed has a greater effect on the bearing ratio curve (Rpk , Rk and Rvk ) parameters with a percentage contribution of 37.68%, 37.65% and 36.91%, respectively. The second significant parameter is the feed rate and the other parameter is significant only in relation to Rpk and Rk parameters.

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Authors and Affiliations

Amine Hamdi
1 2
Sidi Mohammed Merghache
2
Toufik Aliouane
1

  1. Laboratory of Applied Optics (LAO), Institute of Optics and Precision Mechanics, University Ferhat Abbas Setif 1, 19000, Algeria.
  2. Institute of Sciences & Technology, University Center of Tissemsilt, 38000, Algeria.
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Abstract

The aim of the paper is to shed light on the theoretical background of the inclusion of health in the standard of living studies, and the use of two of its specifi c measures — life expectancy at birth and body height. Hence, the article describes the idea of capabilities and functionings developed by Amartya Sen as a proposed solution to the limitations of the classic measurement of the standard of living.

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Authors and Affiliations

Bartosz Ogórek
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Abstract

The present study has been taken up to emphasize the role of the hybridization process for optimizing a given reinforced concrete (RC) frame. Although various primary techniques have been hybrid in the past with varying degree of success, the effect of hybridization of enhanced versions of standard optimization techniques has found little attention. The focus of the current study is to see if it is possible to maintain and carry the positive effects of enhanced versions of two different techniques while using their hybrid algorithms. For this purpose, enhanced versions of standard particle swarm optimization (PSO) and a standard gravitational search algorithm (GSA), were considered for optimizing an RC frame. The enhanced version of PSO involves its democratization by considering all good and bad experiences of the particles, whereas the enhanced version of the GSA is made self-adaptive by considering a specific range for certain parameters, like the gravitational constant and a set of agents with the best fitness values. The optimization process, being iterative in nature, has been coded in C++. The analysis and design procedure is based on the specifications of Indian codes. Two distinct advantages of enhanced versions of standard PSO and GSA, namely, better capability to escape from local optima and a faster convergence rate, have been tested for the hybrid algorithm. The entire formulation for optimal cost design of a frame includes the cost of beams and columns. The variables of each element of structural frame have been considered as continuous and rounded off appropriately to consider practical limitations. An example has also been considered to emphasize the validity of this optimum design procedure.

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Authors and Affiliations

Sonia Chutani
Jagbir Singh
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Abstract

The article raised issues related to the design and execution of low-energy objects in Polish conditions. Based on the designed single-family house, adapted to the requirements of the National Fund for Environmental Protection and Water Management ("NF40" standard), the tools to assist investment decisions by investors were shown. An economic analysis and a multi-criteria analysis were performed using AHP method which had provided an answer to the question whether it is worthwhile to bear higher investment costs in order to adjust to the standards of energy-efficient buildings that fulfil a minimal energy consumption's requirements contained in Polish law. In addition, the variant of object that had optimal characteristics due to the different preferences of investors was indicated. This paper includes analysis and observations on the attempts to unify that part of the building sector, which so far is considered to be personalized, and objects in accordance with the corresponding idea are designed as "custom-made".

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Authors and Affiliations

K. Tomczak
O. Kinash

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