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Search results for: climate%20change
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Disciplines and measures of information resilience
PublicationCommunication networks have become a fundamental part of many critical infrastructures, playing an important role in information delivery in various failure scenarios triggered e.g., by forces of nature (including earthquakes, tornados, fires, etc.), technology-related disasters (for instance due to power blackout), or malicious human activities. A number of recovery schemes have been defined in the context of network resilience...
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The performance of ETFs on developed and emerging markets with consideration of regional diversity
PublicationThis study evaluates the performance of Exchange-Traded Funds (ETFs) by using various tracking error calculation approaches. The aim of the paper is, on the one hand, an evaluation of the performance of ETFs relative to their benchmarking indexes and, on the other, an endeavour to specify any relationship between this performance and both geographical location and the degree of market development. The research was conducted on...
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System architecture of an INSPIRE-compliant green cadastre system for the EU Member State of Poland
PublicationIn response to the need for a sustainable agricultural policy, which would support activities such as decision making in precise agriculture and mitigation of crop threats, a concept agricultural information system was developed for the area of Poland. This innovative concept, called Green Cadastre (GC), proposes to create a uniform system designed for use on a national scale by both state administration as well as local farmers....
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Trendy w e-usługach
PublicationW artykule przedstawiono trendy w sektorze e-biznesu pokazujące perspektywy zmian w usługach. Zwrócono uwagę jak zmienia się podejście do samego procesu usługi, jak zmienia się sposób świadczenia samej usługi. Autor przedstawia trendy nie tylko związane z zastosowaniem nowoczesnych technologii, ale również związane z otwieraniem nowych segmentów rynku jakimi są np. społeczności. W wyniku analizy przytoczonych przykładów wykorzystania...
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A review of design approaches for the implementation of low-frequency noise measurement systems
PublicationElectronic noise has its roots in the fundamental physical interactions between matter and charged particles, carrying information about the phenomena that occur at the microscopic level. Therefore, Low-Frequency Noise Measurements (LFNM) are a well-established technique for the characterization of electron devices and materials and, compared to other techniques, they offer the advantage of being non-destructive and of providing...
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Thermal degradation of polylactic acid (PLA)/polyhydroxybutyrate (PHB) blends: A systematic review
PublicationPolylactic acid (PLA) and polyhydroxybutyrate (PHB) are two biopolyesters obtained from renewable resources like corn or sugar under bacterial fermentation. PLA is the most widely used biopolymer in diverse applications. Addition of PHB to PLA can improves the crystallinity of PLA, and thereby its mechanical strength. However, both PLA and PHB suffer from poor thermal stability, which limits their potential industrial application....
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Thermo-Mechanical Simulation of Underwater Friction Stir Welding of Low Carbon Steel
PublicationThis article investigates the flow of materials and weld formation during underwater friction stir welding (UFSW) of low carbon steel. A thermo-mechanical model is used to understand the relation between frictional heat phenomena during the welding and weld properties. To better understand the effects of the water environment, the simulation and experimental results were compared with the sample prepared by the traditional friction...
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Hydrologiczna analiza odpływu wód opadowych ze zlewni potoku Strzyża w Gdańsku
PublicationNa podstawie Umowy z dnia 02.01.2017r. zawartej pomiędzy Politechniką Gdańską, ul. G. Narutowicza 11/12, 80-233 Gdańsk, a ECE PROJEKTMANAGEMENT POLSKA Sp. z o.o. w Warszawie, ul. Fabryczna 5A, 00-446 Warszawa, została wykonana praca polegające na: przygotowaniu modelu hydrologicznego i hydraulicznego zlewni potoku Strzyża w Gdańsku na rzecz wykonania wielowariantowych obliczeń odpływu wody w przekrojach charakterystycznych dla...
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The early failure of the gamma nail and the dynamic hip screw in femurs with a wide medullary canal. A biomechanical study of intertrochanteric fractures
PublicationBackground: Intertrochanteric fractures may occur in a bone with a wide medullary canal that may lead to significant mobility of a intramedullary nail, contrary to an extramedullary device. This study evaluates the Dynamic Hip Screw and the gamma nail in AO 31.A2.1 fractures in these circumstances. Methods: Synthetic femora with canals drilled to 18 mm were used. Five fixation types were examined: a 2 - hole and a 4 – hole Dynamic...
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Comparative Study of the Mechanical Behaviour of Bitumen- and Cement-Dominated Mixtures with Reclaimed Asphalt
PublicationThe bitumen emulsion-based recycling is a commonly used maintenance treatment in the rehabilitation of low-and medium-volume roads in Europe. Nevertheless, the wide range of climatic conditions across the continent resulted in the variety of mixture concepts and the requirements being adopted for various local conditions. In this regard, the most commonly used parameter to distinguish between the main mixture concepts is bitumen...
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Modeling and optimization of chemical-treated torrefaction of wheat straw to improve energy density by response surface methodology
PublicationToday, torrefaction is important technique for extending the potential of biomass for improvement of energy density. The independent variables investigated for torrefaction study were temperature, retention time, acid concentration, and particle size. The experiment was designed by central composite design (CCD) method using design expert (version 11). The three dependent variables were higher heating value (HHV), energy enhancement...
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Progress towards a unified approach to entanglement distribution
PublicationEntanglement distribution is key to the success of secure communication schemes based on quantum mechanics, and there is a strong need for an ultimate architecture able to overcome the limitations of recent proposals such as those based on entanglement percolation or quantum repeaters. In this work we provide a broad theoretical background for the development of such technologies. In particular, we investigate the question of whether...
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Inwestycja w złoto – bezpieczna przystań, zabezpieczenie czy źródło dywersyfikacji dla polskiego inwestora
PublicationW artykule scharakteryzowano pojęcie inwestycji zabezpieczającej, dywersyfikującej oraz inwestycji określanej jako bezpieczna przystań. Celem opracowania jest zbadanie, czy występują powiązania między stopami zwrotu osiąganymi na polskim rynku akcji a stopami zwrotu z inwestycji w złoto. W pracy zweryfikowano hipotezę: stopa zwrotu z inwestycji w złoto spełnia funkcję inwestycji zabezpieczającej w długim okresie w stosunku do inwestycji...
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Tworzenie wartości dla akcjonariuszy w świetle nadzoru korporacyjnego
PublicationDuży odsetek spółek publicznych w Polsce nie tworzy wartości dla akcjonariuszy. Zaprezento-wano wyniki badań dotyczących wpływu struktur własności na efektywność działania spółek pu-blicznych. Badania te nie były w stanie wyjaśnić w wystarczającym stopniu zjawiska destrukcji warto-ści. Starano się wykazać, że jedną z przyczyn tego zjawiska jest transfer wartości. Zalicza się go do głównych problemów nadzoru korporacyjnego. Szczególna...
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Model of management of knowledge bases in the information technology evaluation environment
PublicationThe paper presents the model of management of knowledge bases in multi-agent system for evaluation of information technologies (IT_MAS). Such system is being developed in Gdansk Uni-versity of Technology by Information Technology Management Team. Multi-agent system is supposed to support manager level specialists during decision processes when there is identified need to buy or change any information technology. The main goal of...
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Fractional neutron point kinetics equations for nuclear reactor dynamics – Numerical solution investigations
PublicationThis paper presents results concerning numerical solutions to a fractional neutron point kinetics model for a nuclear reactor. The paper discusses and expands on results presented in (Espinosa-Paredes et al., 2011). The fractional neutron point kinetics model with six groups of delayed neutron precursors was developed and a numerical solution using the Edwards’ method was proposed (Edwards et al., 2002). The mathematical model...
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Microwave Ring Resonator Based Pressure Sensor
PublicationThis paper demonstrates a microwave pressure sensor, which is based on microstrip line-fed ring resonators. The first ring resonator is loaded with the concentric cylindrical shafts, while the same number of the hollow shanks as the shafts are mounted on the second ring resonator. The arrangement of the cylindrical shaft and hollow shank allows for mechanical movement between two substrates while maintaining electrical contact....
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UK travel agents’ evaluation of eLearning courses offered by destinations: an exploratory study.
PublicationThis study aims to develop an understanding of the use of e-learning courses created for travel agents by Destination Management Organizations (DMOs). It explores agents’ perceptions of such courses. The research examines the views of 304 UK-based travel agents using online survey and investigates whether age, sex, type of agency, work experience, and educational level have influence on e-learning uptake. The satisfaction of travel...
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ADAPTIVE IDENTIFICATION OF TIME-VARYING IMPULSE RESPONSE OF UNDERWATER ACOUSTIC COMMUNICATION CHANNEL
PublicationThe transmission properties of underwater acoustic communication channel can change dynamically due to the movement of acoustic system transmitter and receiver or underwater objects reflecting transmitted signal. The time-varying impulse response measurement and estimation are necessary to match the physical layer of data transmission to instantaneous channel propagation conditions. Using the correlative measurement method, impulse...
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Positive solutions to fractional differential equations involving Stieltjes integral conditions
PublicationIn this paper, we investigate nonlocal boundary value problems for fractional differential equations with dependence on the first-order derivatives and deviating arguments. Sufficient conditions which guarantee the existence of at least three positive solutions are new and obtained by using the Avery–Peterson theorem. We discuss problems (1) and (2) when argument b can change the character on [0, 1], so in some subinterval I of...
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Challenges in providing support for management of evidence-based arguments
PublicationThe paper considers selected challenges related to the application of evidence based arguments and maps them on the tool support level. In particular, we consider: communication and teamwork, handling large arguments, evidence management and integration, argument assessment and communication, change control and reporting, evidence reuse, user data security and argument portfolio management. Then we explain how these challenges...
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Effect of shallow traps on admittance spectra of the system carrying SCLC and on values of charge carrier mobility extracted from susceptance
PublicationThe work concerns small-signal spectra of space-charge-limited current below threshold frequency (ft) of shallow traps. It is shown that below ft the small-signal concentration of trapped charge carriers is proportional to and in phase with small-signal concentration of free charge carriers, so there is no room for “slow shallow traps”. Conductance can be reduced by the traps, however no change in the range of real capacitance...
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Experimental study of boiling heat transfer in the stagnation point of water microjet
PublicationIn the paper presented is a comparison of computational model with experimental data. Numerical model of liquid film with phase change in the stagnation zone due to impingement of the microjet is more widely presented in authors previous work. The radius on which theevaporation process is taking place can be determined from the energy balance on the element of the plate. That radius has also been confirmed experimentally in the...
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High Dynamic Range Microwave Displacement and Rotation Sensors Based on the Phase of Transmission in Groove Gap Waveguide Technology
PublicationThis research is focused on the design and realization of displacement sensors in gap waveguide technology. It is shown that with a small but fundamental change in the structure of a conventional gap waveguide, a linear displacement can be sensed. To this end, a unique feature of gap waveguides, i.e. the fact that no electrical connection between the top and bottom parts of the gap waveguide is required, is used. It is further shown...
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The analysis of temperature changes of the saliva traces left on the fur during laboratory rats social contacts
PublicationAutomatic analysis of complex rodent social be- havior, especially aggressive ones, is of important scientific interest. In this paper we analyze the properties of the data created as a result of aggressive rodent social behavior. Detec- tion of specific aggressive behaviors is based on the event of leaving traces of saliva on the fur of the attacked individual, which are clearly visible in the thermal imaging. The traces change...
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The effect of laser on metal surfaces for multidisciplinary usage in material and thermal engineering
PublicationThe subject of heat transfer and cooling systems is still a matter of contention in many different fields of science and industry. Infrigidation is much more difficult than warming, and so, much more needed in more and more different devices, starting from massive industrial machinery and air conditioning in commercial buildings, up to micro and nano-surgery tools. In fact, the size of many cooling systems is still a problem. It...
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Wavelet Transform Analysis of Temperature Modulated Gas Sensor Response
PublicationThe aim of the study was to evaluate whether it is possible to extract the information about the gas concentration despite the influence of humidity. Commercial semiconductor sensor response was examined under the application of a periodic temperature change. The data was collected using measurement protocol for different concentrations of ammonia at specified levels of relative humidity. In this work we focused on the evaluation...
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Determinants of the surface quality, density and dimensional correctness in selective laser melting of the Ti-13Zr-13Nb alloy
PublicationSelective laser melting is widely used for custom-designed elements. Successful manufacturing depends on laser treatment parameters and material features. This research aimed to determine the effects of laser power, scan time and hatch distance on surface quality, relative density and dimensional precision for cuboids made of the Ti-13Zr-13Nb alloy. The influence of energy density, energy flux and pre-heating was seen to be decisive...
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Impact of new, navigable canal through the Vistula spit on the hydrologic balance of the Vistula lagoon (Baltic Sea)
PublicationThe object of research - the Vistula Lagoon is one of the two lagoons on the Polish coast, which is of great importance not only from an economic point of view, but also an environmental one. The purpose of the paper is to provide calculations on the current water balance for the Vistula Lagoon, before and after construction of a canal through the Vistula Spit. This is important because the construction of a new connection between...
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Intelligent Knowledge-Base Model for IT Support Organization Evolution
PublicationThe goal of the paper is building the knowledge-based model for predicting the state of the IT support organization. These organizations, critical for development of various business sectors, are facing the problem of their transformation. It is the result of the fundamental change in the role of the IT organizations in the current economy. The complexity of the processes, the difficulty adjusting the operations and limited ability...
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Charge density wave and crystalline electric field effects in TmNiC2
PublicationSingle crystals of TmNiC2 were grown by the optical floating-zone technique and were investigated by x-ray diffraction (XRD), thermal expansion, electrical resistivity, specific heat, and magnetic susceptibility measurements. Single-crystal XRD reveals the formation of a commensurate charge density wave (CDW) characterized by a CDW modulation vector q2c = (0.5, 0.5, 0.5), which is accompanied by a symmetry change from the orthorhombic...
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Visible light photoactivity of TiO2loaded with monometallic(Au or Pt) and bimetallic (Au/Pt) nanoparticles
PublicationTiO2modified with monometallic (Au or Pt) and bimetallic (Au/Pt) nanoparticles have been preparedusing a water-in-oil microemulsion system (water/AOT/cyclohexane) followed by calcination step. Theeffect of metal ratio, reducing agent type (NaBH4or N2H4), TiO2matrix type (P-25, ST-01, TiO-5, TiO2nano-tubes or TiO2obtained by TIP hydrolysis) as well as calcination temperature (from 350 to 650◦C) weresystematically investigated. Obtained...
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Interactive and Media Architecture – From Social Encounters to City Planning Strategies
PublicationThe paper searches into the potential of media and interactive projects to support participation and generate social encounters in public spaces. Moreover, it proposes implementation of media and interactive projects into city planning processes. On the basis of theoretical approaches, case studies and interdisciplinary surveys the paper gives insight how interactive and media architecture can engage people in activities in urban...
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One Year Evaluation of Material Properties Changes of Polylactide Parts in Various Hydrolytic Degradation Conditions
PublicationBiodegradable biocompatible materials are widely used in medical applications. Determining the possibility of using biodegradable materials depends on determining the changes in their parameters over time due to degradation. The current scientific research on biodegradable materials has presented results based on research methods characterized by the different geometry and cross-section size of the specimen, type of degradation...
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Experimental Investigations on the Influence of Coil Arrangement on Melting/Solidification Processes
PublicationThe latent heat thermal energy storage units are very popular because of their high energy density and almost close to constant temperature during the charging/discharging. In the present study has been proposed new shell-and-coil geometry with a shifted coil position to enhance the performance of phase change thermal magazine. The experimental investigations have been performed both for the melting and solidification process of...
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Genotoxicity of selected pharmaceuticals, their binary mixtures, and varying environmental conditions – study with human adenocarcinoma cancer HT29 cell line
PublicationPharmaceutical residues are present in the environment in mixtures and their adverse effects may also result from interactions that occur between compounds. Studies presented in this work focus on genotoxicity of pharmaceuticals from different therapeutic groups in mixtures and in individual solutions impacted with different environmental conditions assessed using comet assay (alkaline approach). Binary mixtures of pharmaceuticals...
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Fabrication methods of smart composite coatings - review
PublicationPostoperative bacterial infections are one of the main reasons for unsuccessful implantation of long-term implants. The development of bacterial infection requires antibiotic therapy, in extreme cases a reimplantation procedure is necessary. In order to provide materials for implants with antibacterial properties, they are subjected to modifications to create a coating that will release the drug substance, when the inflammation...
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The Changing Nature of In‐Between Spaces in the Transformation Process of Cities
PublicationIn the in‐between spaces of cities, there are many problems of various nature and scale: functional, spatial, economic, environmental, visual, and social. There are also some hidden potentials that can be activated. The aim of the article is to explore the possibilities of solving existing problems and to show the possibilities of using the potentials of in‐between spaces with regard to the changing nature of a city. The article,...
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Influence of the low ambient temperature on the start-up process of hydraulic pumps
PublicationStarting hydraulic pumps in low ambient temperatures may cause: decreased hydraulic-mechanical efficiency, larger vibration of hydraulic installation, faster wear and more frequent damage to the elements of pumps, change of material properties of elements, increase of pressure drop. As a result of pressure drop in the suction pipe, large underpressure may be experienced, causing incomplete filling of pump working chambers with...
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Small Hydropower Plants in Pomerania: The Example of Evolution of Modern Industrial Brick Architecture
PublicationModernism is usually recognized and associated with the aesthetics of the International Style, represented by white-plastered, horizontally articulated architecture with skimpy decoration, where function was the main imperative of the architects’ ambitions. The brick face of Modernism in Northern Europe reflected, in fact, the complexity of the modern change, breaking ties with the historic styles of the 19th century and being...
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Experimental study and numerical simulation on porosity dependent direct reducibility of high-grade iron oxide pellets in hydrogen
PublicationThe transition to more environmentally friendly steel production methods has intensified research into hydrogen-based direct reduction (HyDR) of iron oxide pellets. The aim of this study is to systematically investigate the kinetics of the reduction process, the evolution of porosity and the resulting microstructural changes on the reduction behavior of high-quality pellets during HyDR of iron ore at different temperatures. A modified...
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Komunikacja między komputerem a procesorem sygnałowym z zastosowaniem protokołu RTDX. Zastosowanie Komputerów w Nauce i Technice. XIII cykl seminariów zorganizowanych przez PTETiS, Oddział Gdańsk.
PublicationW artykule opisano możliwości realizacji komunikacji między komputerem osobistym a procesorem sygnałowym TMS320C6711 firmy Texas Instruments. Scharakteryzowano własności karty uruchomieniowej ze zmiennoprzecinkowym procesorem sygnałowym TMS320C6711 pod kątem zastosowań dydaktyczno-naukowych. Przedstawiono przykłady praktycznych rozwiązań procedur komunikacyjnych, utworzonych w środowiskach programistycznych Visual C++ oraz LabView,...
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Capturing semantics of semi-structured data using partial-order trees
PublicationW artykule zaprezentowano nowe podejście do problemu klasyfikacji danych semistrukturalnych. Kryteria klasyfikacji bazują na strukturze danych (zwanej typem danych) oraz na ich usytuowaniu w grafir danych (zwanym rolą danych). Zastosowano model OEM (Object Exchange Model) do reprezentacji nazy danych semistrukturalnych. Bazując na tej reprezentacji, definiuje się typy i role obiektów semistrukturalnych i organizuje się je w struktury...
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Exploring the Benefits, Challenges, and Opportunities of Collaborative Business Intelligence
PublicationIn traditional business intelligence (BI) settings, the collective decision-making process is often hindered by the absence of knowledge and expertise exchange among various stakeholders, as well as lack of information sharing. The study delves into the concept of Collaborative BI, which aims to overcome these limitations by promoting collaboration, business networking, knowledge sharing, and improved communication among stakeholders....
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Using Synchronously Registered Biosignals Dataset for Teaching Basics of Medical Data Analysis – Case Study
PublicationMedical data analysis and processing strongly relies on the data quality itself. The correct data registration allows many unnecessary steps in data processing to be avoided. Moreover, it takes a certain amount of experience to acquire data that can produce replicable results. Because consistency is crucial in the teaching process, students have access to pre-recorded real data without the necessity of using additional equipment...
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JUST CULTURE MATURITY QUESTIONNAIRE VALIDATION IN A POLISH HOSPITAL
PublicationPurpose: (To present the results of the statistical validation of just culture maturity questionnaire (JCMQ), used to recognize the maturity level of JC among nurses in the hospital in Poland. Methodology: (The case study and 5-stage research with the use of a 5-point Likert scale questionnaire with 28 statements, distributed among nurses. The results were statistically processed with Statistica 13.1 software. Findings: We confirmed...
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Stock price reactions to an arrangement approval in restructuring proceedings – the case of Poland
PublicationThe study aims to empirically analyze the reaction of stock prices to the information about the conclusion and acceptance of a debtor–creditor arrangement under restructuring proceedings of companies listed on the stock exchange in Poland. The following main research hypothesis was verified: public disclosure of information about an arrangement conclusion and acceptance in restructuring proceedings...
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Comparison of the coordination geometries of Zn(II) and Cd(II) ions in complexes with water, methanol and bulky aryloxysilanethiolate ligands
PublicationZinc and cadmium complexes containing silanethiolate anions and methanol or water were synthesized and characterized by X-ray diffraction, FT-IR and NMR spectroscopy, and DFT calculations. Contrary to zinc, the cadmium ion utilizes very weak donors to complete its coordination sphere; it forms contacts to phenyl rings of the silanethiolate ligand. Two zinc analogs of the general formula [Zn{SSi(OAr)3}2(L)2] where L = CH3OH (2)...
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Modeling energy consumption of parallel applications
PublicationThe 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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Security Information Sharing for the Polish Power System
PublicationThe Polish Power System is becoming increasingly more dependent on Information and Communication Technologies which results in its exposure to cyberattacks, including the evolved and highly sophisticated threats such as Advanced Persistent Threats or Distributed Denial of Service attacks. The most exposed components are SCADA systems in substations and Distributed Control Systems in power plants. When addressing this situation...