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On the influence of the acceleration recording time on the calculation of impact severity indexes
PublicationThe paper concerns with the analysis of normative requirements pertaining to experimental setup of a crash test and its numerical modelling. An overview of parameters describing the collision of a vehicle with a road restraining system is presented. A short description of a concrete road safety barrier is presented. A brief description of numerical modelling procedures for crash tests is given as well. The parametric influence...
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Ship Dynamic Positioning Based on Nonlinear Model Predictive Control
PublicationThe presented work explores the simulation test results of using nonlinear model predictive control algorithm for ship dynamic positioning. In the optimization task, a goal function with a penalty was proposed with a variable prediction step. The results of the proposed control algorithm were compared with backstepping and PID. The effect of estimation accuracy on the control quality with the implemented algorithms was investigated....
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Prediction of flow boiling heat transfer coefficient for carbon dioxide in minichannels and conventional channels
PublicationIn the paper are presented the results of calculations using authors own model to predict heat transfer coefficient during flow boiling for carbon dioxide. The experimental data from various researches were scrutinised conducted for a full range of quality variation and wide range of mass velocity. The aim of the study was to test the sensitivity of the in-house model. The work shows the importance of taking into account surface...
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Zero-visibility cops and robber and the pathwidth of a graph
PublicationWe examine the zero-visibility cops and robber graph searching model, which differs from the classical cops and robber game in one way: the robber is invisible. We show that this model is not monotonic. We show that the zero-visibility copnumber of a graph is bounded above by its pathwidth and cannot be bounded below by any nontrivial function of the pathwidth. As well, we define a monotonic version of this game and show that the...
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Equivalent standard manoeuvres for pod-driven ships
PublicationProcedures for carrying out the manoeuvring tests presented in International Maritime Organisation (IMO) resolution MSC.137(76) are based on the capabilities of ships with conventional steering-propulsion systems. Therefore they do not correspond to ships with other steering-propulsion devices, like pod drives. IMO is aware of this shortcoming and for ships with non-conventional steering and propulsion system may permit the use...
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Evaluation of possibilities in identification and susceptibility testing for Candida glabrata clinical isolates with the Integral System Yeast Plus (ISYP)
PublicationThe aim of this study was to evaluate possibilities of correct identification and susceptibility testing of C. glabrata clinical isolates with Integral System Yeast Plus (ISYP). For species identification, as the reference method, API Candida test and species-specific PCR reactions were used. The potential of antifungal susceptibility testing by the ISYP test was compared with the Sensititre Yeast One. Whilst the reference methods...
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Realization, programming and controlling of the Stewart-Gough platform
PublicationThis paper presents realizaon, programming, and controlling of a low cost Stewart-Gough plaorm (SGP) with rotary actuators. The realized SGP is applied in a ball & plate control system. Developed dedicated software consists of embedded and applicaon soware for both the SGP posioning system and the ball & plate control. system. A ball posion is being obtained using computer vision. The paper contains tests results for both an SGP...
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Depth Determination Accuracy of the Modified Prony Method in a Swath Mapping Application
PublicationThis article presents the performance of the modified Prony method in a swath mapping application. Depth determination accuracy is assessed by processing raw signal acquired by an EdgeTech 6205 swath bathymetry system over flat seafloor. An updated version of the method, proposed previously by the authors, is used to determine the number of signal echoes. The number of signal echoes is essential for performing the low-rank approximation...
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TRAVELLING WAVES FOR LOW–GRADE GLIOMA GROWTH AND RESPONSE TO A CHEMOTHERAPY MODEL
PublicationLow-grade gliomas (LGGs) are primary brain tumours which evolve very slowly in time, but inevitably cause patient death. In this paper, we consider a PDE version of the previously proposed ODE model that describes the changes in the densities of functionally alive LGGs cells and cells that are irreversibly damaged by chemotherapy treatment. Besides the basic mathematical properties of the model, we study the possibility of the...
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An Improvement of Global Complex Roots and Poles Finding Algorithm for Propagation and Radiation Problems
PublicationAn improvement of the recently developed global roots finding algorithm has been proposed. The modification allows to shorten the computational time by reducing the number of function calls. Moreover, both versions of the algorithms (standard and modified) have been tested for numerically defined functions obtained from spectral domain approach and field matching method. The tests have been performed for three simple microwave...
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Pomoszcz Ministerstwa Inostrannych del Polszy Armenji, Azerbejdzżany i Gruzji = Polish Development Assistance for Armenia, Azerbaijan and Georgia
PublicationGeorgia has been one of the priority areas of development assistance of Polish Ministry of Foreign Affairs from 2004, because it plays a important role in Polish forsign policy in the framework of the Eastern Partnership. The largest amounts of development aid supporting the transformation were allocated for this country. Since founding the Eastern Partnership initiative in 2009 also Azerbaijan and Armenia have been included to...
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Evolutionary Ship Track Planning within Traffic Separation Schemes – Evaluation of Individuals
PublicationThe paper presents an extended version of the author’s Evolutionary Sets of Safe Ship Trajectories method. The method plans safe tracks of all ships involved in an encounter including speed reduction manoeuvres, if necessary, and taking into account Rule 10 of COLREGS, which specifies ships’ behaviour within Traffic Separation Schemes governed by IMO. The paper focuses on the evaluation phase of the evolutionary process and shows...
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Implementation of magnitude calculation of complex numbers using improved alpha max plus beta min algorithm
PublicationThe paper presents the hardware implementation of the improved alpha max plus beta min algorithm for calculating the magnitude of complex numbers. This version of the algorithm requires the general division which is performed using a noniterative multiplicative division algorithm. We analyze in detail the division algorithm, its error and the impact of finite word-length signal representations on the assumed total computation error....
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Shaft friction from the DMT and direct shear interface tests
PublicationThe article presents preliminary attempt to create tri-linear transfer curves for describing pile behaviour under axial loading. Transfer curves would use the parameter measured in dilatometer test, particularly a constrained modulus MDMT. The proposed method is based on concrete rough and smooth interface tests performed in a direct shear apparatus. Based on the obtained mobilization curves, relationships were created between...
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Performance of Coherent Modulation Scheme Used in Acoustic Underwater Communication System
PublicationThe development of an acoustic underwater communication system for shallow waters is still a big scientificand construction challenge. Currently, non-coherent modulations in combination with strong channel coding are used to achieve reliable communication with low rate in such a channel. To obtain transmission with a higher transmission rate, it is required to use coherent modulation. This paper presents the assumptions of such...
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Adapting Agile Practices to Security Context – Practitioners’ Perspective
PublicationIn this paper we explore the problem of introducing agile practices to projects dealing with systems with high security requirements. We also propose an approach based on AgileSafe method and OWASP ASVS guidelines, that could support such introduction. What is more, we present the results of two surveys aimed at analyzing IT practitioners’ views on applying agile methods to security reliant systems as well as evaluating the set...
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Audio-visual aspect of the Lombard effect and comparison with recordings depicting emotional states.
PublicationIn this paper an analysis of audio-visual recordings of the Lombard effect is shown. First, audio signal is analyzed indicating the presence of this phenomenon in the recorded sessions. The principal aim, however, was to discuss problems related to extracting differences caused by the Lombard effect, present in the video , i.e. visible as tension and work of facial muscles aligned to an increase in the intensity of the articulated...
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Teleportation of geometric structures in 3D
PublicationThe simplest quantum teleportation algorithms can be represented in geometric terms in spaces of dimensions 3 (for real state vectors) and 4 (for complex state vectors). The geometric representation is based on geometric-algebra coding, a geometric alternative to the tensor-product coding typical of quantum mechanics. We discuss all the elementary ingredients of the geometric version of the algorithm: geometric analogs of states...
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Displacement control in PWK-type pumps
PublicationThe most important, strategic goal however is creation of the variable displacement version of the new pump PWK. Thanks to full discharge of it's commutation mechanism from hydrostatic forces the variable pump can be directly controlled by low-energy actuator like proportional electromagnet or stepping motor. It means that costly and complicated hydraulic servomechanism (applied in all present variable displacement pumps) is no...
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FPGA computation of magnitude of complex numbers using modified CORDIC algorithm
PublicationIn this work we present computation of the magnitude of complex numbers using a modified version of the CORDIC algorithm that uses only five iterations. The relationship between the computation error and the number of CORDIC iterations are presented for floating-point and integer arithmetics. The proposed modification of CORDIC for integer arithmetic relies upon the introduction of correction once basic computations are performed...
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FPGA realization of an improved alpha max plus beta min algorithm
PublicationThe generalized improved version of the alpha max plus beta min square-rooting algorithm and its realization in the Field Programmable Gate Array (FPGA) are presented. The algorithm computes the square root to calculate the approximate magnitude of a complex sample. It is especially useful for pipelined calculations in the DSP. In case of four approximation regions it is possible to reduce the peak error form 3.95% to 0.33%. This...
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On a design of a torque sensor for the iCub humanoid robot
PublicationThe paper presents the evaluation process of a first version of the one axis torque sensor designed for the iCub humanoid robot. Newly designed strain gauges equipped sensor was found to show a significant readouts hysteresis, therefore several tests were run to define the reason of the hysteresis. Some of the design issues met while testing the new sensor are discussed including the screws connection and relative rigidity of the...
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Identification of Bodner-Partom Viscoplastic Model Parameters for Some Aluminum Alloys at Elevated Temperature
PublicationThe paper presents the identification process of inelastic (viscoplastic) properties for two aluminum alloys at a temperature of 120°C. The material parameters are calculated on the basis of uniaxial tension tests. Twelve tests at elevated temperature for each alloy have been performed—three tests for four different strain rates. The main purpose of the paper is to identify the Bodner-Partom viscoplastic model parameters for two...
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Stability of an imperfect truss loaded by wind
PublicationThe present paper is devoted to the numerical research of stability of a truss loaded by wind and stiffened by elastic supports located at the top chord. The lateral braces or lateral and torsional braces were taken into account. In this paper, the linear buckling analysis re- sults for the beam and shell model were presented. Two different shapes of initial geometric imperfections were considered in the non-linear static analysis...
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Evolutionary Sets of Safe Ship Trajectories: problem dedicated operators
PublicationThe paper presents the optimization process of the evolutionary sets of safe ship trajectories method, with a focus on its problem-dedicated operators. The method utilizes a customized evolutionary algorithm to solve a constrained optimization problem. This problem is defined as finding a set of cooperating trajectories (a set is an evolutionary individual) of all the ships involved in the encounter situation. The resulting trajectories...
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Geometric Algebra Model of Distributed Representations
PublicationFormalism based on GA is an alternative to distributed representation models developed so far-Smolensky's tensor product, Holographic Reduced Representations (HRR) and Binary Spatter Code (BSC). Convolutions are replaced by geometric products, interpretable in terms of geometry which seems to be the most natural language for visualization of higher concepts. This paper recalls the main ideas behind the GA model and investigates...
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Experiments on Preserving Pieces of Information in a Given Order in Holographic Reduced Representations and the Continuous Geometric Algebra Model
PublicationGeometric Analogues of Holographic Reduced Representations (GAc, which is the continuous version of the previously developed discrete GA model) employ role-filler binding based on geometric products.Atomic objects are real-valued vectors in n-dimensional Euclidean space and complex statements belong to a hierarchy of multivectors. The property of GAc and HRR studied here is the ability to store pieces of information in a given...
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Roof over PGE Arena in Gdansk. Review of structure and monitoring system
PublicationThis paper presents general structural assumptions of the steel construction designed for a newfootball stadium to be built for UEFA Championship 2012 in the city of Gdańsk. The superstructureis founded directly on the modified abutment. The facade and the roof are collected from 82 steelgirders made of tube profiles. The girders are braced by circular beams and X tension rods. All thiscreates a quasi - dome covered by polycarbonate...
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Bringing Bathymetry LiDAR to Coastal Zone Assessment: A Case Study in the Southern Baltic
PublicationOne of the major tasks in environmental protection is monitoring the coast for negative impacts due to climate change and anthropopressure. Remote sensing techniques are often used in studies of impact assessment. Topographic and bathymetric procedures are treated as separate measurement methods, while methods that combine coastal zone analysis with underwater impacts are rarely used in geotechnical analyses. This study presents...
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Wire Arc Additive Manufactured Mild Steel and Austenitic Stainless Steel Components: Microstructure, Mechanical Properties and Residual Stresses
PublicationWire arc additive manufacturing (WAAM) is an additive manufacturing process based on the arc welding process in which wire is melted by an electric arc and deposited layer by layer. Due to the cost and rate benefits over powder-based additive manufacturing technologies and other alternative heat sources such as laser and electron beams, the process is currently receiving much attention in the industrial production sector. The gas...
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A comparison of geometric analogues of holographic reduced representations, original holographic reduced representations and binary spatter codes
PublicationGeometric Analogues of Holographic Reduced Representations (GA HRR) employ role-filler binding based on geometric products. Atomic objects are real-valued vectors in n-dimensional Euclidean space and complex statements belong to a hierarchy of multivectors. The paper reports a battery of tests aimed at comparison of GA HRR with Holographic Reduced Representation (HRR) and Binary Spatter Codes (BSC). Firstly, we perform a test of...
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Synthesis, Chemical Characterization and Multiscale Biological Evaluation of a dimericcRGD Peptide for Targeted Imaging of αVβ3 Integrin Activity
PublicationCyclic peptides containing the Arg-Gly-Asp (RGD) sequence have been shown to specifically bind the angiogenesis biomarker α V β3 integrin. We report the synthesis, chemical characterization, and biological evaluation of two novel dimeric cyclic RGD-based molecular probes for the targeted imaging of α V β3 activity (a radiolabeled version, 64Cu-NOTA-PEG4-cRGD2, for PET imaging, and a fluorescent version, FITC-PEG4-cRGD2, for in...
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NEW EXPERIENCES IN DIKE CONSTRUCTION WITH SOIL-ASH COMPOSITESAND FINE-GRAINED DREDGED MATERIALS
PublicationThe supporting structure inside a coastal dike is often made of dredged non-uniform sand with good compaction proper-ties. Due to the shortage of natural construction material for both coastal and river dikes and the surplus of different processed mate-rials, new experiments were made with sand-ash mixtures and fine-grained dredged materials to replace both dike core and dikecover materials resulting in economical, environmentally...
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Investigating the Effects of Geometrical Parameters of Re-Entrant Cells of Aluminum 7075-T651 Auxetic Structures on Fatigue Life
PublicationIn this study, the effects of two geometrical parameters of the re-entrant auxetic cells, namely, internal cell angle (θ) and H/L ratio in which H is the cell height, and L is the cell length, have been studied on the variations of Poisson’s ratio and fatigue life of Aluminum 7075-T6 auxetic structures. Five different values of both the H/L ratio and angle θ were selected. Numerical simulations and fatigue life predictions have...
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KONCEPCJA WSPÓŁPRACY SYSTEMU STRUMIENIOWEJ TRANSMISJI DANYCH CZASU RZECZYWISTEGO STRADAR Z EUROPEJSKIM SYSTEMEM EUROSUR
PublicationPrzedstawiono koncepcję współpracy systemów STRADAR i EUROSUR, w celu wymiany informacji związanych z ochroną granic UE. Opisano cechy zrealizowanego demonstratora STRADAR i zasady komunikacji oraz bezpieczeństwa wymiany informacji w systemie EUROSUR. Opisano warianty wymiany infor-macji pomiędzy systemami STRADAR i EUROSUR, od najprostszych, możliwych do zastosowania w obecnej wersji STRADAR, do zautomatyzowanych, wymagających...
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Measurements of acoustic crosstalk cancellation efficiency in mobile listening conditions
PublicationThe cancellation of acoustic crosstalk is employed to enhance the stereo image in mobile listening conditions. The implementation of the crosstalk cancellation algorithm in Matlab is introduced. The measurement signals and equipment are described. A practical setup employing a mobile computer and a head and torso simulator is employed. The results of the measurements provided conclusions regarding the employment of acoustic crosstalk...
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Improving the Performance of Ontological Querying by using a Contextual Approach
PublicationIn the paper we present the results of experiment we performed to determine whether a contextual approach may be used to increase the performance of querying a knowledge base. For the experiments we have used a unique setting where we put much effort in developing a contextual and a non-contextual ontology which are as much close counterparts as possible. To achieve this we created a contextual version...
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EXPERIMENTAL AND NUMERICAL VALIDATION OF THE IMPROVED VORTEX METHOD APPLIED TO CP745 MARINE PROPELLER MODEL
PublicationThe article presents a numerical analysis of the CP745 marine propeller model by means of the improved vortex method and CFD simulations. Both numerical approaches are validated experimentally by comparing with open water characteristics of the propeller. The introduced modification of the vortex method couples the lifting surface approach for the propeller blades and the boundary element method for the hub. What is more, a...
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Airborne and mobile laser scanning in measurements of sea cliffs on the southern Baltic
PublicationMeasurements of sea cliffs performed using periodic surveying based on laser scanning is currently one of the fastest and most accurate solutions. Supported with the technology of satellite measurements using GNSS (Global Navigation Satellite System) positioning and photographic measurements with the use of aerial vehicle, they enable an effective monitoring of the sea cliffs affected by the erosion. In case of the coast of southern...
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Coastal Cliffs Monitoring and Prediction of Displacements Using Terrestial Laser Scanning
PublicationCoastal cliffs are very sensitive to degradation caused by erosion and abrasion. Thus, it is very important to monitor susceptibility of the cliffs in terms of slope angles and ground fall resulting from vertical morphology of the cliffs. The results could be used for example to establish the boundaries of the safe investments zone or retreat infrastructure buildings in case of real threat such as degradation of the objects of...
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Style Transfer for Detecting Vehicles with Thermal Camera
PublicationIn this work we focus on nighttime vehicle detection for intelligent traffic monitoring from the thermal camera. To train a Convolutional Neural Network (CNN) detector we create a stylized version of COCO (Common Objects in Context) dataset using Style Transfer technique that imitates images obtained from thermal cameras. This new dataset is further used for fine-tuning of the model and as a result detection accuracy on images...
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Convergence of rational multistep methods of of Adams-Padé type
PublicationRational generalizations of multistep schemes, where the linear stiff part of a given problem is treated by an A-stable rational approximation, have been proposed by several authors, but a reasonable convergence analysis for stiff problems has not been provided so far. In this paper we directly relate this approach to exponential multistep methods, a subclass of the increasingly popular class of exponential integrators. This natural,...
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Evolutionary Sets of Safe Ship Trajectories: Evaluation of Individuals
PublicationThe paper presents a description of the evaluation phase of the Evolutionary Sets of Safe Ship Trajectories method. In general, the Evolutionary Sets of Safe Ship Trajectories method combines some of the assumptions of game theory with evolutionary programming and finds an optimal set of cooperating trajectories of all ships involved in an encounter situation. While developing a new version of this method, the authors decided to...
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Outlet Flow Velocity In Circular Culvert
PublicationThe outlet flow velocity in the end section of the culvert barrel depends in most cases on the culvert geometry, including the barrel slope, as well as on upstream and downstream channel parameters. Flowing water can create pressure flow or free surface flow in the culvert barrel. In the case of an unsubmerged barrel outlet, the free-surface flow is more frequent than the full flow. Increased velocities can cause channel bed scour...
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(R,R)-1-Acetyl-1'-(2,4,6-trinitrophenyl)-2,2'-bipyrrolidine
Publication(R,R)-1-Acetyl-1'-(2,4,6-trinitrophenyl)-2,2'-bipyrrolidine has been synthesized and its rentgenostructure has been determined. The structure of the title molecule, C16H19N5O7, is mainly determined by the steric effect of a bulky 2,4,6-trinitrophenyl group attached to the N atom of a pyrrolidine ring. Both pyrrolidine rings adopt an envelope conformation, with one of the methylene C atoms as the flap in each case, and the N-C-C-N...
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BODIPY‐Perylene Charge Transfer Compounds; Sensitizers for Triplet‐Triplet Annihilation Up‐conversion
PublicationBODIPY heterochromophores, asymmetrically substituted with perylene and/or iodine at the 2 and 6 positions were prepared and investigated as sensitizers for triplet-triplet annihilation up conversion (TTA-UC). Single-crystal X-ray crystallographic analyses show that the torsion angle between BODIPY and perylene units lie between 73.54 and 74.51, though they are not orthogonal. Both compounds show intense, charge transfer absorption...
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Application of surface active amino acid ionic liquids as phase-transfer catalyst
PublicationFive structurally related morpholinium derived ionic liquids containing N-acetyl-glycinate anion were synthesized and their thermal stability, surface properties and activity as phase transfer catalysts investigated. The thermal properties were studied by differential scanning calorimetry, while the adsorption at the air/water interface and micellization behavior was analyzed by surface tension measurements, conductometry and isothermal...
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Awaria ściany szczelinowej stanowiącej obudowę wykopu głębokiego
PublicationW artykule przedstawiono awarię ściany szczelinowej stanowiącej obudowę wykopu głębokiego. Omówiono warunki geologiczne, hydrogeologiczne i geotechniczne podłoża. Przeprowadzono analizę rozwiązań konstrukcyjnych w kolejnych oszczędnościowych modyfikacjach projektu oraz zrealizowanej wersji. Wykonano obliczenia porównawcze. Wskazano przyczyny wystąpienia awarii. In the paper a failure of diaphragm wall protecting deep excavation...
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Navigating the complexities of altruistic helping in Nonprofit Organizations: An analysis of Benefits, Burdens and managerial challenges
PublicationWe investigate how individuals cope with side effects of altruistic behaviour at work, i.e. genuine helping behaviour which is not part of any job description, and what role the organizational context plays in these dynamics. Employing simultaneous dyadic interviews, we show how employees of non-profit organizations cope with undesired effects of altruistic help. Our data provides evidence of unintended outcomes for the individual...
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Evolutionary Sets of Safe Ship Trajectories: Evaluation of Individuals
PublicationThe paper presents a description of the evaluation phase of the Evolutionary Sets of Safe Ship Trajectories method. In general, the Evolutionary Sets of Safe Ship Trajectories method combines some of the assumptions of game theory with evolutionary programming and finds an optimal set of cooperating trajectories of all ships involved in an encounter situation. While developing a new version of this method, the au-thors decided...