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Number of results: 16
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Abstract

The aim of this article is substantially devoted to explore which factors have, and have had, an impact on the way history is actually explained. The main topics are: - The fundamental passage from a monological interpretation of history to a "plurality of voices", linked to post-modern culture. The complex debate about Post-modern culture is significantly marked by the disappearance of the monology (a great cultural uniting discourse) and by the emergence of different interpretations and visions. This process has a clear influence on the way history is now explained and the way the "official history" has been substituted by different narratives. The meaning of collective memory. The role of collective memory has acquired a renewed significance today, scholars belonging to different disciplines have underlined its importance in the nation-building processes or in the re-affirmation of identity. For example, ten years after the fall of the Berlin Wall, the passing of time is producing peculiar interpretations and alterations about the recent history of the former socialist countries. The history of these new democratic societies has been re-written, not in the oriented and "orwellian" way, followed by the previous regimes, but through the subtle, complex and spontaneous work of the collective memory. The political and ideological action oriented to "create" or to "erase" historical events, which can be functional to the elites legitimisation. Elites need a symbolic background to support their political action and to maintain the consensus of society. They are able both to create new myths or partisan visions that can undermine the legitimacy of a political system and to support real democratic societies.
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Authors and Affiliations

Antonella Pocecco
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Abstract

Multiple historians as well as sociologists gradually recognize the multiple parallels joining their disciplines. This is a reason for the Authors of the paper to launch a concept of the "History-Sociology" as a new, matrix discipline in humanities.
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Authors and Affiliations

Janusz Goćkowski
Anna Woźniak
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Abstract

The article presents a comparative analysis of various classifi cations of both sciences’ and management sciences’ paradigms in terms of their pragmatism and adequacy regarding organization research. Furthermore, the aim of the article is also to justify the thesis about the high usefulness of research model proposed by Keneth D. Strang. Strang’s model, based on the concept of researcher’s socio-cultural philosophy, allows on the one hand to overcome the theoretical incommensurability and on the other hand makes it possible for representatives of various paradigms to cooperate with each other. The article contains also refl ections on the paradigm as a key factor affecting both the development of management sciences and the practice of management. The choice of a specifi c paradigm, i.e. research ideology, has a decisive impact on the results of research, as well as the generalization of practice. The paradigm defi nes the research strategy, selection of research methods and inference rules. Furthermore, it infl uences the education process, and thus has an impact on shaping the worldview of scientists, entrepreneurs as well as managers.

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Authors and Affiliations

Bronisław Bombała
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Abstract

Basing on the first and second law of thermodynamics the fundamental trends in the Polish energy policy are analysed, including the aspects of environmental protection. The thermodynamical improvement of real processes (reduction of exergy losses) is the main way leading to an improvement of the effectivity of energy consumption. If the exergy loss is economically not justified, we have to do with an error from the viewpoint of the second law analysis. The paper contains a thermodynamical analysis of the ratio of final and primary energy, as well as the analysis of the thermo-ecological cost and index of sustainable development concerning primary energy. Analyses of thermo-ecological costs concerning electricity and centralized heat production have been also carried out. The effect of increasing the share of high-efficiency cogeneration has been analyzed, too. Attention has been paid to an improved efficiency of the transmission and distribution of electricity, which is of special importance from the viewpoint of the second law analysis. The improvement of the energy effectivity in industry was analyzed on the example of physical recuperation, being of special importance from the point of view of exergy analysis.
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Authors and Affiliations

Andrzej Ziębik
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Abstract

Technology advancements entail a necessity to remove huge amounts of heat produced by today’s electronic devices based on highly integrated circuits, major generators of heat. Heat transfer to boiling liquid flowing through narrow minichannels is a modern solution to the problem of heat transfer enhancement. The study was conducted for FC-72 boiling in a rectangular, vertical and asymmetrically heated minichannel that had depths of 0.5-1.5 mm, a width of 20 mm and a length of 360 mm. The heat flux increased and decreased within the range of 58.3-132.0 kWm−2, the absolute pressure ranged from 0.116 to 0.184 MPa and the mass flux was 185-1139.2 kgm−2s−1. The boiling process took place on a flat vertical heating surface made of Haynes-230 0.1 mm thick acid-proof rolled plate with the surface roughness of 121 μm.

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Authors and Affiliations

Robert Kaniowski
Mieczysław Poniewski
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Abstract

In this study, the influences of different parameters at performance two-phase closed thermosiphon (TPCT) was presented. It has been confirmed that the working fluid, as well as operating parameters and fill ratio, are very important factors in the performance of TPCT. The article shows characteristics of gravitational tube geometries, as well as the technical characteristic of the most important system components, i.e., the evaporator/condenser. The experiment’s plan and the results of it for the two-phase thermosiphon for both evaluated geometries with varying thermal and fluid flow parameters are presented. Experiments were performed for the most perspective working fluids, namely: water, R134a, SES36, ethanol and HFE7100. Obtained research proves the possibility to use TPCT for heat recovery from the industrial waste water.

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Authors and Affiliations

Rafał Andrzejczyk
Tomasz Muszyński
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Abstract

Heat exchangers of different types find application in power systems based on solid oxide fuel cells (SOFC). Compact plate fin heat exchangers are typically found to perfectly fit systems with power output under 5 kWel. Micro-combined heat and power (micro-CHP) units with solid oxide fuel cells can exhibit high electrical and overall efficiencies, exceeding 85%, respectively. These values can be achieved only when high thermal integration of a system is assured. Selection and sizing of heat exchangers play a crucial role and should be done with caution. Moreover, performance of heat exchangers under variable operating conditions can strongly influence efficiency of the complete system. For that reason, it becomes important to develop high fidelity mathematical models allowing evaluation of heat exchangers under modified operating conditions, in high temperature regimes. Prediction of pressure and temperatures drops at the exit of cold and hot sides are important for system-level studies. Paper presents dedicated mathematical model used for evaluation of a plate fin heat exchanger, operating as a part of micro-CHP unit with solid oxide fuel cells.

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Authors and Affiliations

Jakub Kupecki
Krzysztof Badyda
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Abstract

Cold-formed structure connections utilizing gusset plates are usually semi-rigid. This paper investigates the behaviours of rectangular gusset plates in cold-formed connections of elements whose columns and beams are made with lipped back-to-back C-sections. Methods of calculating strength and stiffness are necessary for such semi-rigid joints. The main task of this paper is to determine a method capable of calculating these characteristics. The proposed analytical method could then be easily adapted to the component method that is described in part 1993-1-8 of the Eurocode. This method allows us to calculate both the strength and stiffness of rectangular gusset plates, assuming that the joint deforms only in plane. This method of design moment resistance calculation was presented taking into account that an entire cross-section shall reach its yield stress. A technique of stiffness calculation was presented investigating the sum of deformations acquired at the bending moment and from shear forces which are transmitted from each beam bolt group. Calculation results according to the suggested method show good agreement of laboratory experimental results of specimens with numerical simulations. Two specimens of beam-to-column connections were tested in the laboratory. Lateral supports were used on the specimens to prevent lateral displacements in order to better investigate the behaviour of the rectangular gusset plate in plane. Experiments were simulated by modelling rectangular gusset plates using standard finite element software ANSYS Workbench 14.0. Three-dimensional solid elements were used for modelling and both geometric and material nonlinear analysis was performed.

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Authors and Affiliations

Ž Bučmys
A. Daniūnas
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Abstract

The present paper consists of two parts. The first part presents theoretical foundations of Msplit, estimation with reference to the previous author's paper (Wiśniewski, 2009). This time, some probabilistic assumptions are described in detail. A new quantity called f-information is also introduced to formulate the split potential in more general way. The main aim of this part of the paper is to generalize the target function of Msplit estimation that is the basis for a new formulation of the optimization problem. Such problem itself as well as its solution are presented in this part of the paper. The second part of the paper presents some special case of Mspli, estimation called squared Mspli, estimation (also with reference to the mentioned above paper of the author). That part presents a new solution and development in the theory of this version of M,plit estimation and some numerical examples that show properties of the method and its application scope.
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Authors and Affiliations

Zbigniew Wiśniewski
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Abstract

The article presents the results of numerical and analytical investigations of the influence of raw liquid natural gas (LNG) composition on parameters characterizing the combustion process. The high content of higher hydrocarbons influences the thermodynamic combustion process described with parameters like the adiabatic flame temperature, laminar flame speed and ignition delay time. A numerical study of the impact of LNG fuels on emission characteristics using the Cantera code has been performed. Results have shown that the change of grid natural gas to some types of liquid natural gas can result in an incomplete combustion process and an increase of emission of toxic compounds such as carbon monoxide and unburned hydrocarbons. For all investigated fuels the laminar flame speed rises by about 10% compared to natural gas, while the adiabatic flame temperature is nearly the same. The ignition delay time is decreased with an increase of ethane share in the fuel. The analysis of chemical pathways has shown that hydrogen cyanide and hydrogen formation is present, particularly in the high temperature combustion regimes, which results in an increase of nitric oxide molar fraction in flue gases by even 10% compared to natural gas. To summarize, for some applications, liquid natural gases cannot be directly used as interchangeable fuels in an industry sector, even if they meet the legal requirements.
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Authors and Affiliations

Paweł Czyżewski
1
Rafał Ślefarski
1
Joanna Jójka
1

  1. Poznan University of Technology, Institute of Thermal Energy, Piotrowo 3a, 60-965, Poznan, Poland
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Abstract

The emission of dust from power and industrial sources introduces a lot of contaminants into the air, including compounds of trace clements contained in fuels and raw materials. They arc contained in rcspirablc dust particles, creating hazard to human health. The results of investigations into the occurrence of selected trace clements in PM1, PM25 and PM10 fractions of dust emitted from coal-fired boilers equipped with air protection devices such as cyclone, clectrofiltcr, wet and dry-scrubbing FGD plant have been presented. Dust emitted from a coke battery (battery heating) and rotary kiln for cement manufacture was also subjected to research. The research material was taken by means of a cascade impactor, enabling a fraction or different grain size dust to be separated from a stream of dust collected in an elcctrofiltcr. The ICP-AES method (of atomic emission spectrometry (AES) with plasma excitation) was used to determine the trace clements alter prior mineralization of samples by microwave method. The results of measurements and analyses were presented by determining the ranges of trace elements occurrence in flue dust and emission factors in PM,s It was found out that big utility boilers and rotary kilns in the cement industry which are equipped with air protection devices meeting BAT requirements do not contaminate the air with dust and dust-related trace elements in the amounts that could create hazard. Excessive emission of dust, including a resp i rabie fraction is still observed in the case of municipal heating plants equipped solely with mechanical dust separators (cyclones). Coke battery heating docs not pose danger due to small range of influence.
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Authors and Affiliations

Jan Konieczyński
Katarzyna Stec
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Abstract

Per- and polyfl uoroalkyl substances (PFASs) are human-invented chemicals that were created in the middle of the 20th century. They were synthesized for the fi rst time in 1949, and because of their exceptional surfactant properties, they have been widely used in many industrial applications and daily life products. The common use of PFASs resulted in their worldwide dissemination in natural environment. PFASs are reported to be ubiquitous in surface and drinking waters, but also may be present in soils, animals, milk and milk-products, plants, food. Contaminated drinking water and food are the most signifi cant exposure sources to these chemicals. Ingested PFASs are bio-accumulative and have adverse eff ect on health of humans as well as animal organisms. This paper reviews the most signifi cant information on the origin, properties, distribution, environmental fate, human exposure, health eff ects, and the environmental regulations on PFASs and summarizes the latest advances in the development of novel methods for the eff ective removal of these chemicals from the aqueous environment. Recognized (reverse osmosis, adsorption on activated carbon) and most promising developing removal methods such as adsorption on biomaterials (plant proteins, chitosan beds), mineral adsorbents (LDHs, hydrotalcite), ionexchange resins, and photocatalytic degradation have been emphasized.

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Authors and Affiliations

Mariusz Grabda
1
Sylwia Oleszek
2
Michiaki Matsumoto
3

  1. General Tadeusz Kosciuszko Military University of Land Forces, Wroclaw, Poland
  2. Department of Environmental Engineering, Kyoto University, Kyoto, Japan
  3. Department of Chemical Engineering and Materials Science, Doshisha University, Kyoto, Japan
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Abstract

This study is focused on the image analysis of motionless hydraulic mixing process, for which pressure changes were the driving force. To improve the understanding of hydraulic mixing, mixing efficiency was assessed with dye introduction, which resulted in certain challenges. In order to overcome them, the framework and methodology consisting of three main steps were proposed and applied to an experimental case study. The experiments were recorded using a camera and then processed according to the proposed framework and methodology. The main outputs from the methodology which were based only on the recorded movie were liquid heights and colour changes during the process time. In addition, considerable attention has also been given to issues related to other colour systems and the hydrodynamic description of the process.
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Authors and Affiliations

Aleksandra Golczak
1
Waldemar Szaferski
1
ORCID: ORCID
Szymon Woziwodzki
1
Piotr T. Mitkowski
1
ORCID: ORCID

  1. Poznan University of Technology, Department of Chemical Engineering and Equipment, Berdychowo 4, 60-965 Poznan, Poland
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Abstract

Whatever the type of surgery related to inner organs, traditional or robotic, the contact with them during surgery is a key moment for pursuing the intervention. Contacts by means of surgery instruments namely scalpels, staples, clamps, graspers, etc. are decisive moments. False, and erroneous touching and manoeuvring of organs operated on can cause irreversible damage as regard morphological aspects (outer impact) and physiological aspects (inner impact). The topic is a great challenge in the effort to measure and characterize damages. In general, electrical instruments for surgery employ the following technologies: ultrasound, radiofrequency (monopolar, and bipolar), and laser. They all result in thermal damages difficult to evaluate. The article proposes a method for a pre-screening of organ features during robotic surgery sessions by pointing out mechanical and thermal stresses. A dedicated modelling has been developed based on experimental activities during surgery session. The idea is to model tissue behaviour from real images to help surgeons to be aware of handling during surgery. This is the first step for generalization by considering the type of organ. The measurement acquisitions have been performed by means of an advanced external camera located over the surgery quadrant. The modelling and testing have been carried out on kidneys. The modelling, carried out through Comsol Multiphysics, is based on the bioheat approach. A further comparative technique has been implemented. It is based on computer vision for robotics. The findings of human tissue behavior exhibit reliable results.
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Authors and Affiliations

Aimé Lay-Ekuakille
1
Moise Avoci Ugwiri
2
Consolatina Liguori
2
Satya P. Singh
3
Md Zia Uhr Rahman
4
Domenico Veneziano
5

  1. University of Salento, Department of Innovation Engineering, Via Monteroni sn, 73100 Lecce, Italy
  2. University of Salerno, Department of Industrial Engineering, Via Giovanni Paolo II n.132, 84084 Fisciano, Italy
  3. Nanyang Technological University, School of Computer Science and Engineering, 50 Nangyang Ave, Singapore 639798
  4. K L University, Department of Electronics & Communication Engineering, Green Fields, Vaddeswaram, Guntur-522502, India
  5. Asl Reggio Calabria, Hospital “Bianchi-Melacrino-Morelli”, Via Giuseppe Melacrino n.21, 89124 Reggio Calabria, Italy
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Abstract

Taking debates on the historiography of Quebec as the base of his considerations, the Author presents various reflections and postulates concerning comparative historiography. In particular His attention is drawn to the various types and aspects of historical identity. The awareness of those is necessary for the correct comparative analysis.
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Authors and Affiliations

Chris Lorenz
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Abstract

Samples for the study were collected from, known from the literature, outcrop profiles in Zarzecze, Radymno, Dybawka, Tarnawce and Pikulice-Nehrybka, situated at the Carpathian border, in the vicinity of the Przemyśl town, close to the San River valley (SE Poland). They represent the Vistulian loess-palaeosol sequences. Carbonates occur mainly in the loesses representing OIS 2 and 3. Pollen analysis, carried out for two profiles (Tarnawce, Radymno), throws light on palaeoecological conditions of loess cover formation and transformation.Isotopic analysis of authigenic carbonates was carried out on carbonate cemented bodies dispersed throughout the loess in forms of nodule, rhizolith and rhizocretion and on bioclasts, mainly snail shells, ostracod valves, and sparse globules (probably the internal shells of the naked snails).In the successions studied, the upper Vistulian loess deposited in environment with poor vegetation, contains rhizo- liths and rhizocretions mainly, while in the middle and lower Vistulian loess with well developed soils, gley horizons, and intercalations of subaqueous sediments, remains of snail shells and ostracod valves prevail. The two main forms of carbonates differ markedly in isotopic composition from one another. These differences seem to be more important than those between samples of one form of carbonates along particular sections. That is the result of numerous factors affecting the fractionation of carbon and, in particular, oxygen stable isotopes in the environment of precipitation of authigenic calcite. The isotopic composition of carbonates cementing sediments is controlled mainly by biominerali- zation of organic matter and local climatic parameters which were rather slightly differentiated during the formation of the studied sediments. The d13C values for bioclasts vary in a broader range than for calcitic cements. Usually the snail shell carbonate is more enriched with heavier carbon isotope than that from ostracod valves, resulting from the isotopic equilibrium with precipitation and with surface waters, respectively. Basing on our study we can conclude that fluctuations of isotope composition of authigenic carbonates make it hard to apply as a paleoclimatic indicator. However, the general trend of d18O variation in analysed carbonate fractions from leoss-palaeosol sequences displays some connections with climatic fluctuations.

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Authors and Affiliations

Bożena Łącka
Maria Łanczont
Maryna Komar
Teresa Madeyska

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