Wyniki wyszukiwania dla: WEAR AND TEAR PROCESSES - MOST Wiedzy

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Wyniki wyszukiwania dla: WEAR AND TEAR PROCESSES

Wyniki wyszukiwania dla: WEAR AND TEAR PROCESSES

  • Natalia Sokół dr inż.

    BACKGROUND       Master of Science in Light and Lighting (2008-2009/11) The UCL Bartlett School of Graduate Studies, Faculty of the Built Environment, London, UK, www.bartlett.ucl.ac.uk       MA Degree in Interior Architecture (1999-2004), The Academy of Fine Arts, Poznan, Poland, www.uap.edu.pl       MA Degree in Art Education (1997-2002), Academy of Fine Arts, Poznan, Poland, www.uap.edu.pl MAIN RESEARCH AREAS ·         ...

  • Understanding the formation of metastable furan dication in collisions with ions

    Publikacja
    • E. Erdmann
    • S. Indrajith
    • J. Chiarinelli
    • S. Díaz-Tendero
    • N. F. Aguirre
    • M. Alcamí
    • A. Domaracka
    • P. Rousseau
    • B. A. Huber
    • P. Bolognesi... i 2 innych

    - Journal of Physics : Conference Series - Rok 2020

    This work relies on complementary theoretical and experimental studies of the processes induced by ion-furan collisions. Results of the Molecular Dynamics simulations and exploration of the energy profiles combined with coincidence mass spectrometry provide complete picture of the fragmentation of furan dication.

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  • Grzegorz Zieliński dr inż.

    Autor ponad 100 publikacji naukowych (zarówno w języku polskim, jak i angielskim) z zakresu zarządzania działalnością usługową, doskonalenia podmiotów, w tym podmiotów leczniczych. Zainteresowania naukowo-badawcze obejmują obszary związane z dojrzałością i doskonałością przedsiębiorstw w różnych aspektach ich działalności. Uczestniczył w projektach badawczych Narodowego Centrum Nauki oraz projektach realizowanych przez międzynarodowe...

  • A review on gasification and pyrolysis of waste plastics

    Publikacja

    - Rok 2023

    Gasification and pyrolysis are thermal processes for converting carbonaceous substances into tar, ash, coke, char, and gas. Pyrolysis produces products such as char, tar, and gas, while gasification transforms carbon-containing products (e.g., the products from pyrolysis) into a primarily gaseous product. The composition of the products and their relative quantities are highly dependent on the configuration of the overall process...

  • A Strategy for Managing the Operation of Technical Infrastructure Based on the Analysis of “Bad Actors”—A Case Study of LOTOS Group S.A.

    Publikacja

    - Sustainability - Rok 2022

    The article covers issues related to the selection of a management strategy for the operation of technical infrastructure. It contains the approaches, methodology and a general model of the system of operation of the Maintenance Services of the LOTOS Group production company, which is an example of a large oil concern. Nowadays, an increasing aspect is put on the efficiency of individual repair processes, as well as the operation...

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  • The Multiplatform Environment for Simulation and Features Estimation of Mixed-Signal Devices

    Publikacja

    - Rok 2019

    The use of simulation laboratories is gaining popularity in thedomains of engineering programs. However, the experience in teaching showsthat the simulation itself is not very effective in didactic processes. Teachingprocesses in thefield of specialist subjects, designed for students of technicaluniversities, should be based on direct operations performed by the student onreal devices. At the same time, at the later stages of didactic...

  • Piotr Grudowski dr hab. inż.

    Dr hab. inż. Piotr Grudowski, profesor w Politechnice Gdańskiej karierę naukową rozpoczynał na Wydziale Mechanicznym Technologicznym Politechniki Gdańskiej w zespole „Inżynierii Jakości i Metrologii”. Stopień doktora nauk technicznych w dyscyplinie budowa i eksploatacja maszyn uzyskał w roku 1993 na Wydziale Mechanicznym PG a stopień doktora habilitowanego nauk ekonomicznych, w dyscyplinie nauk o zarządzaniu, w 2008 roku na Wydziale...

  • THE CASE OF MANAGEMENT CONCEPTS IN CIVIL AVIATION BUSINESS.

    Publikacja

    The article presents the changes in management concepts used in civil aviation business in last 25 years. There is a need to make prognosis and support decision-making processes with different models but each model is adapted to current management concept. This article will present the changes and possible future trends in management concepts with the description of strengths and weaknesses of each of them. These might be used...

  • Employees’ self-expansion as a mediator between perceived work conditions and work engagement and productive behaviors

    Publikacja

    - Rok 2019

    There has been increasing scientific interest in the relationships between self-perception and group identity development processes as well as the behavioural implications of these processes in organizational contexts. Recently, the concept of workplace self-expansion has been introduced to work and organizational psychology. That is, the self-expanding characteristics of work and the workplace have been related to job satisfaction...

  • Application of the near-infrared spectroscopy in the pharmaceutical technology

    Near-infrared (NIR) spectroscopy is currently the fastest-growing and the most versatile analytical method not only in the pharmaceutical sciences but also in the industry. This review focuses on recent NIR applications in the pharmaceutical technology. This article covers monitoring, by NIR, of many manufacturing processes, such as granulation, mixing or drying, in order to determine the end-point of these processes. In this...

  • Balancing Energy Inputs/Outputs and GHG Emissions for Sustainable Wastewater Treatment – a Case Study

    Publikacja

    - Rok 2017

    The aim of the study is a model-based evaluation of the selected operating modes and technological upgrades on the energy balance and greenhouse gas (GHG) emissions in a large wastewater treatment plant in the city of Slupsk (northern Poland). The considered scenarios focus on energy savings for aeration, increasing energy recovery via biogas cogeneration and reduction of the CO2 equivalent emission from both direct processes (related...

  • The role of epigenetics in regeneration

    Publikacja

    Complex changes in chromatin structure and at the transcriptional level occur from the creation of a single parental gamete throughout fertilization, embryo development and the life of an adult organism. Epigenetic changes, such as methylation and hydroxymethylation of DNA or histone methylation and acetylation, are an important part of these processes. Epigenetic regulation has an essential influence on gene expression level. DNA...

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  • Turbulence models impact on the flow and thermal analyses of jet impingement

    Publikacja
    • T. Kura
    • E. Fornalik-Wajs
    • J. Wajs
    • S. Kenjeres

    - MATEC Web of Conferences - Rok 2018

    Accurate numerical reconstruction of heat and mass transfer processes in particular applications, such a jet impingement, is difficult to obtain even with the use of modern computational methods. In the proposed paper, the flow and thermal phenomena occurring during single minijet impingement on the flat, concave and convex, heated surfaces were considered. Problem of impingement on non-flat surface, still not common and purely...

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  • Deregulation of the labour markets in the countries of Central and Eastern Europe — selected issues

    The countries of Central and Eastern Europe in the 1990s pursued the transformation processes which were to result in introducing systemic changes and building market economies. It was a process requiring adjustment of the regulatory and system framework to the requirements of the EU. One of the areas covered by the changes was the labour market. The reforms related to the functioning of national labour markets necessitated taking...

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  • Smart Innovation Engineering: Toward Intelligent Industries of the Future

    Publikacja

    - CYBERNETICS AND SYSTEMS - Rok 2018

    Knowledge-based Engineering Systems are founded upon integration of knowledge into computer systems and are one of the core requirements for the future Industry 4.0. This paper presents a system called Smart Innovation Engineering (SIE) capable of facilitating product innovation process semi-automatically. It enhances decision-making processes by using the explicit knowledge of formal decision events. The SIE system carries the...

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  • How can analysts use multicriteria decision analysis?

    Proper decision making in multifacitated situation is very challenging task. It is especially difficult if there are many alternatives and criteria that are often contradictory. Analytical chemistry and related sciences involve many situations where decisions on complex problems are made. The support tools may be the use of MCDA (Multi-criteria Decision Analysis) algorithms. They formalize the decision process, make it transparent...

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  • Nina Rizun dr

    Nina Rizun jest adiunktem na Wydziale Zarządzania i Ekonomii Politechniki Gdańskiej. W  październiku 1999 r. uzyskała stopień doktora nauk technicznych za specjalizacją Gospodarka przedsiębiorstwa i organizacja produkcji. W latach 1993–2000 pracowała na Wydziale Informatyki Ekonomicznej w Akademji Metalurgicznej, Dnipro, Ukraina. W latach 2000–2016 – na Wydziale Cybernetyki Ekonomicznej i Metod Matematycznych na Uniwersytecie Alfreda...

  • Janusz Kozak prof. dr hab. inż.

    Dr hab. inż. Janusz Kozak Dziekan Wydziału Oceanotechniki i Okrętownictwa Politechniki Gdańskiej   Urodzony: 04.07.1953 w Pucku Absolwent Technikum Budowy Okrętów „Conradinum” w Gdańsku, 1973. Absolwent Instytutu Okrętowego PG, 1978.   Po ukończeniu studiów praca w Stoczni Gdynia, a od roku 1980 w Katedrze Technologii Okrętów Instytutu Okrętowego a później Wydziału Oceanotechniki i Okrętownictwa Politechniki Gdańskiej kolejno na...

  • Równolegle przebiegające procesy separacji pianowej jonów Al(III), Cu(II) i Zn(II) z roztworów ich mieszanin

    Publikacja

    - Rok 2015

    Metody flotacji jonowej i precypitacyjnej należą do procesów separacji pianowej, wykorzystujących zdolność selektywnej adsorpcji niektórych składników roztworu na powierzchni międzyfazowej gaz – ciecz. Do zalet separacji pianowej zalicza się m.in. niewysokie koszty inwestycyjne i eksploatacyjne oraz wysoką skuteczność w obróbce roztworów rozcieńczonych. Celem pracy jest ocena wpływu kluczowych parametrów na wydajność i przebieg...

  • DLC coating doped with W in ring-on-ring sliding with saline solution (0.9% wt.) lubrication 20MPa/0.1m/s

    Dane Badawcze

    Wear tests in sliding friction of 1% W (tungsten) doped DLC coating on 1.4021 (EN 10088-1) heat treated stainless steel. Ring - on - ring contact in unidirectional sliding, DLC-W over DLC-W. Mean contact stress: 20MPa. Sliding velocity: 0,1 m/s. Mean friction radius: 9.5mm. Lubricant: SALINE SOLUTION (0.9% wt.). Tribometer: PT-3. Overall test time >15h....

  • DLC coating doped with W in ring-on-ring sliding with saline solution (0.9% wt.) lubrication 10MPa/0.1m/s

    Dane Badawcze

    Wear tests in sliding friction of 1% W (tungsten) doped DLC coating on 1.4021 (EN 10088-1) heat treated stainless steel. Ring - on - ring contact in unidirectional sliding, DLC-W over DLC-W. Mean contact stress: 10MPa. Sliding velocity: 0,1 m/s. Mean friction radius: 9.5mm. Lubricant: SALINE SOLUTION (0.9% wt.). Tribometer: PT-3. Overall test time >15h....

  • Statistics of AFM current-voltage curves

    Dane Badawcze

    Mapping surface electrical conductivity offers enormous cognitive possibilities regarding the structure and properties of modern materials. The technique invented for this purpose (Conductive AFM) by Murrel's team and colleagues allows independent monitoring of the local conductivity of materials in correlation with the topographic profile. The mentioned...

  • Selected issues on inovativeness of enterprises in Poland

    The article presents the issue of innovative activities in company processes. The forms of innovative activity important from the point of view of industrial, trade and service enterprises were described. The influence of different types of implemented innovations on the possible benefits obtained by enterprises was also described.

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  • High-performance activation of ozone by sonocavitation for BTEX degradation in water

    Publikacja

    This work presents a novel advanced oxidation process (AOP) for degradation of emerging organic pollutants – benzene, toluene, ethylbenzene and xylenes (BTEXs) in water. A comparative study was performed for sonocavitation assisted ozonation under 40–120 kHz and 80–200 kHz dual frequency ultrasounds (DFUS). Based on the obtained results, the combination of 40–120 kHz i.e., low-frequency US (LFDUS) with O3 exhibited excellent oxidation...

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  • The concept of stream and system reliability on the example of the bakery industry

    Publikacja

    This article presents a new concept of technological system reliability based on the analysis of the relationship of associations of elements of energy streams, matter, information, time and finance. The method of stream specification and the method of determining the reliability values of significant and supporting relationships are given. Relevant relationships between elements of system streams were defined as having one-time...

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  • The chemistry of river–lake systems in the context of permafrost occurrence (Mongolia, Valley of the Lakes). Part I. Analysis of ion and trace metal concentrations

    Publikacja

    - SEDIMENTARY GEOLOGY - Rok 2016

    This study provides a description of water chemistry in river–lake systems located in central Mongolia, at the borderline of permafrost occurrence. The analysis involved water samples collected from two river–lake systems: Baydrag River–Böön Tsagaan Lake system, and Shargalyuut/Tuyn Rivers–Orog Lake system. In the water samples, ions and trace elements were detected and quantified. Additionally, the parameters of pH, electrical...

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  • Advanced Supervisory Control System Implemented at Full-Scale WWTP—A Case Study of Optimization and Energy Balance Improvement

    Publikacja

    - Water - Rok 2019

    In modern and cost-eective Wastewater Treatment Plants (WWTPs), processes such as aeration, chemical feeds and sludge pumping are usually controlled by an operating system integrated with online sensors. The proper verification of these data-driven measurements and the control of different unit operations at the same time has a strong influence on better understanding and accurately optimizing the biochemical processes at WWTP—especially...

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  • KM Challenges in Small KIBS Companies: Multi-case Analysis in Two Countries

    Publikacja

    - Rok 2023

    Knowledge Intensive Business Services (KIBS) – i.e. companies like e.g. computer services, consulting, engineering, business communication, and R&D support - are key players in the modern economies. They stimulate the innovativeness of businesses and societies. Their competitiveness is based on knowledge, which is their key production factor and also the kind of “goods” they sell. The large majority of KIBS companies have a small...

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  • Sieć sensorowa do rejestracji drgań górnej sieci trakcyjnej w celach diagnostyki eksploatacyjnej

    Wraz ze wzrostem prędkości kolejowych pojazdów elektrycznych zwiększają się wymagania utrzymania sieci trakcyjnej w odpowiednim stanie technicznym. Ciągły monitoring i diagnostyka pozwalają wykrywać pogarszającą się jakość odbioru prądu z sieci jezdnej. Jedną z metod jest umieszczenie czujników przyspieszenia na przewodzie jezdnym. Analiza przebiegu przyspieszenia pozwala określić jakość współpracy sieci jezdnej z pantografem....

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  • Tensile curve of E grade steel for shipbuilding

    Dane Badawcze
    open access

    In the shipbuilding industry, the risk of brittle fractures developing in constructions is limited by employing certified materials of specific impact strength, determined using the Charpy method (for a given design temperature) and by exercising control over the welding processes (technology qualification, supervision of production, tests of non-destructive...

  • Piotr Zawadzki mgr inż.

    Osoby

    Piotr Zawadzki w 2018 r. ukończył studia na Wydziale Energetyki i Inżynierii Środowiska Politechniki Śląskiej w Gliwicach. Obecnie pracuje w Zakładzie Ochrony Wód w Laboratorium Technologii Wody i Ścieków, Głównego Instytutu Górnictwa. Jego zainteresowania badawcze obejmują eliminację mikrozanieczyszczeń ze środowiska człowieka z wykorzystaniem napędzanych światłem widzialnym zaawansowanych procesów utleniania, w tym z rodników...

  • Polymer journal bearings behaviour research under limited lubrication and cooling conditions conducted on high torque test rig

    Publikacja

    Polymer journal bearings are frequently used as a water-lubricated bearings of small marine units’ propeller shafts . Choice of these bearings is based on their simple construction and relatively low purchase and maintenance costs. Although properly designed and installed water lubricated bearings may well last for over a decade, rapid wear or failure of these bearings can be observed...

  • Effects of the Origin and Deacetylation Degree of Chitosan on Properties of Its Coatings on Titanium

    Publikacja

    The properties of chitosan coatings on titanium surfaces may be influenced by a variety of factors, including their chemical characteristics and the deposition method. The aim of this research was to determine the influence of a chitosan’s origin (a type of shrimp) and deacetylation degree (DD), when deposited on a very smooth titanium surface, on adhesion and biological behavior. The tests were performed using chitosan of a degree...

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  • Bibliometric analysis and literature review of ultrasound-assisted degradation of organic pollutants

    Publikacja

    - SCIENCE OF THE TOTAL ENVIRONMENT - Rok 2023

    Ultrasound as a clean, efficient, and cheap technique gains special attention in wastewater treatment. Ultrasound alone or coupled with hybrid processes have been widely studied for the treatment of pollutants in wastewater. Thus, it is essential to conduct a review about the research development and trends on this emerging technique. This work presents a bibliometric analysis of the topic associated with multiple tools such as...

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  • Marta Kuc-Czarnecka dr

    Marta Kuc-Czarnecka jest zastępczynią kierownika Katedry Statystyki i Ekonomii na Wydziale Zarządzania i Ekonomii Politechniki Gdańskiej. Pełni również funkcję pełnomocniczki Dziekana ds. akredytacji AMBA. Jest współzałożycielką Rethinking Economics Gdańsk oraz członkinią Fundacji im. Edwarda Lipińskiego na rzecz promocji pluralizmu w naukach ekonomicznych. W latach 2018-2022 była ekspertką Europejskiej Fundacji na Rzecz Poprawy...

  • Modeling energy consumption of parallel applications

    The paper presents modeling and simulation of energy consumption of two types of parallel applications: geometric Single Program Multiple Data (SPMD) and divide-and-conquer (DAC). Simulation is performed in a new MERPSYS environment. Model of an application uses the Java language with extension representing message exchange between processes working in parallel. Simulation is performed by running threads representing distinct process...

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  • Laser reflectance interferometry system with a 405 nm laser diode for in-situ measurement of CVD diamond thickness

    In situ monitoring of the thickness of thin diamond films during technological processes is important because it allows better control of deposition time and deeper understanding of deposition kinetics. One of the widely used techniques is laser reflectance interferometry (LRI) which enables non-contact measurement during CVD deposition. The authors have built a novel LRI system with a 405 nm laser diode which achieves better...

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  • Crank–Nicolson FDTD Method in Media Described by Time-Fractional Constitutive Relations

    Publikacja

    - Rok 2024

    In this contribution, we present the Crank-Nicolson finite-difference time-domain (CN-FDTD) method, implemented for simulations of wave propagation in media described by time-fractional (TF) constitutive relations. That is, the considered constitutive relations involve fractional-order (FO) derivatives based on the Grünwald-Letnikov definition, allowing for description of hereditary properties and memory effects of media and processes....

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  • Integration of natural and artificial intelligence in production systems

    Publikacja

    - Rok 2011

    Integration processes play an increasingly important role in modern economy, and seriously co-decide about the effectiveness of the company. Integration phase occurs in the system life cycle by preceding the final stages of its implementation and activation. In turn, used in software engineering (SE) iteration-evolutionary models, such as spiral model make that the integration activities can occur in varying degrees in all phases...

  • Occurrence and Determination of Volatile Fatty Acids in Landfill Leachate and Gas

    Publikacja

    In landfills containing biological matter volatile fatty acids (VFAs) are generated at high rate at the early stage of waste disposal and their content in leachate is high as compared to the leachate from old parts of landfill since they are converted to methane gas. Monitoring of the leachate for the content of VFAs can help determine the processes occurring in waste and possible effect of the leachate on the environment in the...

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  • Occurrence and Determination of Volatile Fatty Acids in Landfill Leachate and Gas

    Publikacja

    In landfills containing biological matter volatile fatty acids (VFAs) are generated at high rate at the early stage of waste disposal and their content in leachate is high as compared to the leachate from old parts of landfill since they are converted to methane gas. Monitoring of the leachate for the content of VFAs can help determine the processes occurring in waste and possible effect of the leachate on the environment in the...

  • A new diagnostic method for evaluation of cardiosurgery wound healing

    Publikacja

    One of important and still unsolved problems in medicine is the question of objective and quantitative evaluation of post-surgery wound healing. The aim of this research is to analyse possibility and value of using the newly elaborated infrared imaging procedure – Active Dynamic Thermography (ADT) – for quantitative description of wound healing processes in cardiosurgery. Both, classical thermal figures of merit as well as ADT...

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  • Effect of pine impregnation and feed speed on sound level and cutting power in wood sawing

    The sound levels along with the cutting power registered during the sawing process of the impregnated and non-impregnated pine wood at two feed speeds are shown and compared in this paper. Statistically significant differences in the acoustic signals occurred at the lower feed rate. The differences became smaller with an increase in the feed speed. In contrast to the sound signal, the differences...

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  • Dynamics of Chains as a Tool to Study Thermomechanical Properties of Proteins.

    Publikacja

    - Rok 2021

    Polymer dynamics can be formulated on different levels of detail. One approach eliminates microscopic degrees of freedom and a polymer molecule is represented by a simplified structure—a chain. In the simplest case monomers of ideal chain have fixed length, and their orientation is independent of the orientations and positions of neighbouring monomers. This is reason that two monomers can co-exist at the same place. Ideal chain...

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  • Food Bioactive Ingredients Processing Using Membrane Distillation

    Publikacja

    Separation processes are an important part of today’s food industries, especially in the case of specific bioactive components due to their health benefits. In general, processing of bioactive food ingredients assumes the introduction of integrated system directed to their separation, fractionation, and recovery. Recently, membrane distillation (MD) has been considered as an alternative membrane-based separation and concentration...

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  • Electrical properties of organic and perovskite systems used in solar cells

    Publikacja

    - Rok 2019

    Nowadays, a great progress in the areas of molecular and hybrid photovoltaics is observed. The devices based on organic and perovskite materials are getting attention mostly due to their low cost production process. However, their efficiency and stability are still lower than for inorganic materials which make them less popular. Therefore, a detailed understanding of the device physics is fundamental for organic and perovskite...

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  • Detection, identification and determination of chiral pharmaceutical residues in wastewater: Problems and challenges

    Chiral pharmaceuticals (CPs) are widely used in different areas of human life, thus they are frequentlydetected in different ecosystems. However, before CPs reach the environment, wastewater is subjected todifferent treatment processes in order to remove them. Nevertheless, such processes may affect thechirality of CPs, thus it is very important to monitor CP levels during the wastewater treatment.This review addresses the present...

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  • Utilization of Gaseous Carbon Dioxide and Industrial Ca-rich Waste for Calcium Carbonate Precipitation: A Review

    Publikacja

    Technologies for the management of various types of waste and the production of useful products from them are currently widely studied. Both carbon dioxide and calcium-rich waste from various production processes are problematic wastes that can be used to produce calcium carbonate. Therefore, the purpose of this paper is to provide an overview about the state of the development of processes that use these two wastes...

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  • Model based evaluation of plant improvement at a large wastewater treatment plant (WWTP)

    In this work, the effect of the improvement carried out at a large-scale wastewater treatment plant (WWTP) was evaluated, by means of modelling works, with the aim to determine the influence of the modernization over the process performance. After modernization, the energy consumption due to the aeration decreased about a 20% maintaining the effluent quality. In order to double-check the good effluent quality, modelling works were...

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  • Creative sprints: an unplanned broad agile evaluation and redesign process.

    Publikacja

    - Rok 2014

    We report how a request for routine usability work rapidly evolved into a novel agile process for evaluation and redesign. This process is described and then analysed to identify reasons for success. This analysis supports realistic knowledge transfer between User Experience professionals by outlining how similar future processes could succeed.

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