Search results for: open data - Bridge of Knowledge

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Search results for: open data

Search results for: open data

  • Thin-walled frames and grids - statics and dynamics

    Publication

    Frames and grids assembled with thin-walled beams of open cross-section are widely applied in various civil engineering and vehicle or machine structures. Static and dynamic analysis of theses structures may be carried out by means of different models, startingfrom the classical models made of beam elements undergoing the Kirchhoff assumptions to the FE discretization of whole frame into plane elements. The former model is very...

  • The IPV6 Deployment - Best practices

    Publication

    - Year 2011

    The new Internet Protocol IPv6 has been regarded for quite a long time as the only option to ensure uninterrupted operation for the Internet service providers andend-users in the current Internet. The article presents important faets about the IPv6, including current statistics of the IPv4 usage, the IPv6 statistics for Poland comparing to the whole Internet. Moreover, this paper shows important aspeets of migration from IPv4 towards...

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  • Canonical switched capacitor converters. Comments, complements, and refinements

    Publication

    - Year 2017

    Switched Capacitor Converters (SCC) form useful blocks in low/medium power applications as they are suitable for integration, both as off-chip and on-chip IC realizations. However, the problem with SCC is that their voltage conversion ratio is topology-dependent. By changing the SC circuit configuration, we can gain control over voltage conversion but the available ratio remains of a discrete nature, i.e. it maps into a countable...

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  • Energy-Aware High-Performance Computing: Survey of State-of-the-Art Tools, Techniques, and Environments

    The paper presents state of the art of energy-aware high-performance computing (HPC), in particular identification and classification of approaches by system and device types, optimization metrics, and energy/power control methods. System types include single device, clusters, grids, and clouds while considered device types include CPUs, GPUs, multiprocessor, and hybrid systems. Optimization goals include various combinations of...

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  • Carsharing - Opportunities and Threats for Cities: Proposals of Solutions for Urban Policy

    Publication

    The carsharing of a current generation is a short-term car renting service with a capability to find in the nearest surrounding a fleet car parked anywhere in the public space where the previous user left it, as well as to book, open, rent and pay of, with the use of a dedicated mobile application. Nowadays, only a minority of municipalities is considering implementing the carsharing in their policies. The lack of awareness of...

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  • On local buckling of cold-formed channel members

    Publication

    The paper deals with local buckling of the compressed flanges of cold-formed thin-walled channel beams subjected to pure bending or axially compressed columns. Arbitrarily shaped flanges of open cross-sections and the web-flange interactions are taken into account. Buckling deformation of a beam flange is described by displacement related to torsion of the flange about the line of its connection with the web. Total potential energy...

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  • Techniczne aspekty niezawodnej chmury obliczeniowej

    Publication

    Powszechnie wykorzystuje się przetwarzanie w chmurze ze względu na redukcję kosztów zakupu sprzętu oraz łatwość zarządzania środowiskiem. W artykule zaproponowano architekturę prywatnej chmury obliczeniowej opracowanej i uruchomionej na Politechnice Gdańskiej, w ramach której wdrożono nowy portal MOST Wiedzy. Technologia wykorzystana do budowy zarówno chmury, jak i portalu wykorzystuje jedynie rozwiązania open source. Omówiono...

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  • Reshaping the Gdańsk Shipyard—The Birthplace of the Solidarity Movement. The Complexity of Adaptive Reuse in the Heritage Context

    Publication

    The Gdańsk Shipyard—the birthplace of the Solidarity movement—is host to a unique example of a multi-layered brownfield redevelopment project, an area that is burdened by a complex history, overlapping heritage, and multiple memories. These circumstances require an integrated yet differentiated approach to the site’s heritage and make the creation of one homogeneous narration of its future impossible. At the same time, the size...

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  • New Challenges in Management and Economics in 21st century. Selected studies and examples

    Publication

    - Year 2020

    In Chapter 1 authors describe the method used to assess the level of readiness of an organization to introduce the Lean Six Sigma concept supporting the Quality 4.0 assumptions, which is gaining more and more interest not only in large organizations, but also in the SME sector. Its use will be illustrated by the example of a small service company. Chapter 2 presents the characteristics of blockchain technology applications in the...

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  • Non-standard contact conditions in generalized continua: microblock contact model for a Cosserat body

    Generalized continuum theories involve non-standard boundary conditions that are associated with the additional kinematic variables introduced in those theories, e.g., higher gradients of the displacement field or additional kinematic degrees of freedom. Accordingly, formulation of a contact problem for such a continuum necessarily requires that adequate contact conditions are formulated for the additional kinematic variables and/or...

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  • Cops, a fast robber and defensive domination on interval graphs

    Publication

    - THEORETICAL COMPUTER SCIENCE - Year 2019

    The game of Cops and ∞-fast Robber is played by two players, one controlling c cops, the other one robber. The players alternate in turns: all the cops move at once to distance at most one each, the robber moves along any cop-free path. Cops win by sharing a vertex with the robber, the robber by avoiding capture indefinitely. The game was proposed with bounded robber speed by Fomin et al. in “Pursuing a fast robber on a graph”,...

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  • Analysis of Failure Mechanism in Joints with Positive Eccentricity in CFS Truss

    The paper presents studies concerning the load-bearing capacity of truss joints with a positive eccentricity resulting from the arrangement of geometric members and the failure mechanisms observed in the joints. Based on the previously conducted experimental study, a numerical model of the tested fragment of the CFS truss with eccentricity in the joint was created and validated. All structural details of the tested truss and the...

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  • Automatic Emotion Recognition in Children with Autism: A Systematic Literature Review

    Publication

    - SENSORS - Year 2022

    The automatic emotion recognition domain brings new methods and technologies that might be used to enhance therapy of children with autism. The paper aims at the exploration of methods and tools used to recognize emotions in children. It presents a literature review study that was performed using a systematic approach and PRISMA methodology for reporting quantitative and qualitative results. Diverse observation channels and modalities...

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  • Aleksander Orłowski dr hab. inż.

    Dr hab. inż. Aleksander Orłowski, profesor PG w Katedrze Zarządzania Wydziału Zarządzania i Ekonomii Politechniki Gdańskiej, v-ce prezes Forum Rozwoju Aglomeracji Gdańskiej. Zawodowo zajmuje się badaniem i rozwojem koncepcji Smart Cities, współautor (2016-2017) badań gotowości do Smart City dziesięciu czołowych polskich urzędów miejskich, autor książki: Model gotowości procesowej urzędu miejskiego dojścia do Smart City (2019)....

  • Silent Signals The Covert Network Shaping the Future

    Publication

    - Year 2007

    Silent Signals The Covert Network Shaping the Future In a world dominated by information flow and rapid technological advancements, the existence of hidden networks and unseen influences has never been more relevant. "Silent Signals: The Covert Network Shaping the Future" delves deep into the mysterious and often opaque world of covert communication networks. This influential work sheds light on the silent...

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  • Verification and Benchmarking in MPA Coprocessor Design Process

    Publication

    - Year 2022

    This paper presents verification and benchmarking required for the development of a coprocessor digital circuit for integer multiple-precision arithmetic (MPA). Its code is developed, with the use of very high speed integrated circuit hardware description language (VHDL), as an intellectual property core. Therefore, it can be used by a final user within their own computing system based on field-programmable gate arrays (FPGAs)....

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  • Constant-Factor Approximation Algorithm for Binary Search in Trees with Monotonic Query Times

    Publication

    - Year 2022

    We consider a generalization of binary search in linear orders to the domain of weighted trees. The goal is to design an adaptive search strategy whose aim is to locate an unknown target vertex of a given tree. Each query to a vertex v incurs a non-negative cost ω(v) (that can be interpreted as the duration of the query) and returns a feedback that either v is the target or the edge incident to v is given that is on the path towards...

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  • Digital Public Service Innovation: Framework Proposal

    Publication

    - Year 2016

    This paper proposes the Digital Public Service Innovation Framework that extends the "standard" provision of digital public services according to the emerging, enhanced, transactional and connected stages underpinning the United Nations Global e-Government Survey, with seven example "innovations" in digital public service delivery -- transparent, participatory, anticipatory, personalized, co-created, context-aware and context-smart....

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  • Quantum metrology: Heisenberg limit with bound entanglement

    Publication

    - PHYSICAL REVIEW A - Year 2015

    Quantum entanglement may provide a huge boost in the precision of parameter estimation. However, quantum metrology seems to be extremely sensitive to noise in the probe state. There is an important still open question: What type of entanglement is useful as a resource in quantum metrology? Here we raise this question in relation to entanglement distillation. We provide a counterintuitive example of a family of bound entangled states...

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  • The complexity of minimum-length path decompositions

    Publication

    - JOURNAL OF COMPUTER AND SYSTEM SCIENCES - Year 2015

    We consider a bi-criteria generalization of the pathwidth problem, where, for given integers k, l and a graph G, we ask whether there exists a path decomposition P of G such that the width of P is at most k and the number of bags in P, i.e., the length of P, is at most l. We provide a complete complexity classification of the problem in terms of k and l for general graphs. Contrary to the original pathwidth problem, which is fixed-parameter...

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  • The electronic structure of p-xylylene and its reactivity with vinyl molecules

    Publication

    The electronic states of p-xylylene molecule were described at the multi-configurational CASSCF/MRMP2 level of theory. The closed-shell singlet state representing the quinoidal p-xylylene molecule was pre-dicted to be the ground electronic state whereas the triplet (benzoidal) and the singlet open-shell states were found to be much higher in energy (by 159 and 423 kJ/mol, respectively, as found at the CASSCF(8,8)/6-31+G(d) level)....

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  • Modelling of FloodWave Propagation with Wet-dry Front by One-dimensional Diffusive Wave Equation

    A full dynamic model in the form of the shallow water equations (SWE) is often useful for reproducing the unsteady flow in open channels, as well as over a floodplain. However, most of the numerical algorithms applied to the solution of the SWE fail when flood wave propagation over an initially dry area is simulated. The main problems are related to the very small or negative values of water depths occurring in the vicinity of...

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  • Energy-Aware Scheduling for High-Performance Computing Systems: A Survey

    Publication

    High-performance computing (HPC), according to its name, is traditionally oriented toward performance, especially the execution time and scalability of the computations. However, due to the high cost and environmental issues, energy consumption has already become a very important factor that needs to be considered. The paper presents a survey of energy-aware scheduling methods used in a modern HPC environment, starting with the...

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  • Theoretical designing of selenium heterocyclic non-fullerene acceptors with enhanced power conversion efficiency for organic solar cells: a DFT/TD-DFT-based prediction and understanding

    In this study, we have designed and explored a new series of non-fullerene acceptors for possible applications in organic solar cells. We have designed four molecules named as APH1 to APH4 after end-capped modification of recently synthesized Y6-Se-4Cl molecule. Density functional theory and time dependent-density functional theory have been employed for computing geometric and photovoltaic parameters of the designed molecules....

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  • Inverse Flood Routing Using Simplified Flow Equations

    Publication

    - WATER RESOURCES MANAGEMENT - Year 2022

    The paper considers the problem of inverse flood routing in reservoir operation strategy. The aim of the work is to investigate the possibility of determining the hydrograph at the upstream end based on the hydrograph required at the downstream end using simplified open channel flow models. To accomplish this, the linear kinematic wave equation, the diffusive wave equation and the linear Muskingum equation are considered. To achieve...

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  • Medical Image Segmentation Using Deep Semantic-based Methods: A Review of Techniques, Applications and Emerging Trends

    Publication

    - Information Fusion - Year 2022

    Semantic-based segmentation (Semseg) methods play an essential part in medical imaging analysis to improve the diagnostic process. In Semseg technique, every pixel of an image is classified into an instance, where each class is corresponded by an instance. In particular, the semantic segmentation can be used by many medical experts in the domain of radiology, ophthalmologists, dermatologist, and image-guided radiotherapy. The authors...

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  • Commonly Accessible Web Service Platform - Wiki-WS

    Publication

    - Year 2012

    Web Service technology on the basis had to supply complete and reliable system components. Nowadays this technology is commonly used by companies providing results of their work to end users and hiding implementation details. This paper presents a SOA-enabled platform - Wiki-WS - that empowers users to deploy, modify, discover and invoke web services. Moreover it discusses concepts and functionalities of this open source management...

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  • Szeregowanie zadań dwuprocesorowych w systemach otwartych

    W pracy rozważany jest problem szeregowania zadań dwuoperacyjnych w systemie otwartym (open-shop), z kryterium minimalizacji długości harmonogramu oraz sumy czasów zakończenia wszystkich zadań. Zakładając jednostkowe czasy wykonywania operacji można stosować efektywne metody chromatyczne rozwiązywania problemu, poprzez sprowadzenie go do modelu grafowego oraz zastosowanie w nim wybranego modelu kolorowania, które pozwala uzyskać...

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  • A Geometrically Simple Compact Wideband Circularly Polarized Antenna

    Publication

    A compact broadband wide-slot circular polarization (CP) antenna is proposed. An inverted L-shape parasitic strip at the open end of a microstrip line extension and a slot modification is applied to attain wideband CP. The advantage of this technique is simplicity which makes it readily re-designable for different frequency bands. To demonstrate the concept, three designs working at different frequencies are obtained. The redesign...

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  • A Broadband Circularly Polarized Wide-Slot Antenna with a Miniaturized Footprint

    Publication

    This letter presents a novel and simple feeding technique for exciting orthogonal components in a wide-slot antenna. In this technique, a rectangular bracket-shape parasitic strip is placed at the open end of the straight microstrip line to excite the fundamental horizontal and vertical components of the circular polarization (CP). The proposed technique—when employed in conjunction with the asymmetrical geometry of coplanar waveguide...

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  • Ship domain applied to determining distances for collision avoidance manoeuvres in give-way situations

    Ship domain is often used in marine navigation and marine traffic engineering as a safety condition. The basic idea behind those applications is that an encounter of two or more ships can be considered safe if neither of ship domains is intruded by other ships. Research utilising this approach has been documented in numerous works, including publications on optimising collision avoidance manoeuvres performed to fulfil domain-based...

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  • The potential of imogolite nanotubes as (co-)photocatalysts: a linear-scaling density functional theory study

    Publication
    • E. Poli
    • J. Elliott
    • L. Ratcliff
    • L. Andrinopoulos
    • J. Dziedzic
    • N. Hine
    • A. Mostofi
    • C. Skylaris
    • P. Haynes
    • G. Teobaldi

    - JOURNAL OF PHYSICS-CONDENSED MATTER - Year 2016

    We report a linear-scaling density functional theory (DFT) study of the structure, wall-polarization absolute band-alignment and optical absorption of several, recently synthesized, open-ended imogolite (Imo) nanotubes (NTs), namely single-walled (SW) aluminosilicate (AlSi), SW aluminogermanate (AlGe), SW methylated aluminosilicate (AlSi-Me), and double-walled (DW) AlGe NTs. Simulations with three different semi-local and dispersion-corrected...

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  • Preparation and Characterization of Microsphere ZnO ALD Coating Dedicated for the Fiber-Optic Refractive Index Sensor

    Publication

    - Nanomaterials - Year 2019

    We report the fabrication of a novel fiber-optic sensor device, based on the use of a microsphere conformally coated with a thin layer of zinc oxide (ZnO) by atomic layer deposition (ALD), and its use as a refractive index sensor. The microsphere was prepared on the tip of a single-mode optical fiber, on which a conformal ZnO thin film of 200 nm was deposited using an ALD process based on diethyl zinc (DEZ) and water at 100 °C....

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  • Sustainable Use of the Catenary by Trolleybuses with Auxiliary Power Sources on the Example of Gdynia

    Publication

    - Infrastructures - Year 2021

    The current developments in onboard power source technology, in particular, traction batteries, open up new potential in trolleybus transport and also make it possible to introduce electric buses. Thus far, trolleybus transport has required the presence of overhead lines (OHL). Introducing trolleybuses with onboard batteries makes it possible to grow the zero-emissions transport network in places with limited power supply capabilities...

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  • Infrared techniques for natural convection investigations in channels between two vertical, parallel, isothermal and symmetrically heated plates

    The effect of the gap width between two symmetrically heated vertical, parallel, isothermal plates on intensity of natural convective heat transfer in a gas (Pr = 0.71) was experimentally studied using the balance and gradient methods. In the former method heat fluxes were determined based on measurements of the voltage and electric current supplying the heaters placed inside the walls. In the latter, heat fluxes were calculated...

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  • Role of surface recombination in perovskite solar cells at the interface of HTL/CH3NH3PbI3

    Publication

    - Nano Energy - Year 2020

    In order to achieve the highest performance of organometal trihalide perovskite solar cells, it is required to recognize the dominant mechanisms which play a key role in a perovskite material. In the following studies, we have focused on the interfacial recombination between the hole transporting layer (HTL) and the perovskite CH3NH3PbI3 in solar cell devices with p–i–n architecture. It has been shown that Cu:NiOx : used as HTL...

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  • Shaping the City Responding to Climate Change – Concept of Development of the Right Bank of the Vistula River in Toruń, Poland,

    Publication

    The problems of cities of the 21st century are caused by anthropogenic oppression of the environment, through the growth of economic activity and continuous urbanisation, and taking away ecologically important open areas and biologically active areas. Increasingly frequent and sudden rains, strong winds, turbulence and rising world water levels are some of the consequences of climate change that have a direct impact on the functioning...

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  • Synthesis and Physicochemical Characteristics of Chitosan-Based Polyurethane Flexible Foams

    Publication

    - Processes - Year 2021

    The use of shrimp waste to obtain chitosan (Ch) is an essential issue, considering a circular economy, waste management, and its application to environmentally friendly materials. In this study, northern prawn shells were utilized to obtain Ch, which could then be used for synthesizing chitosan-based polyurethane (PUR+Ch) foams with different Ch concentration. The chemical structure, morphology, hardness, thermal properties, viscoelastic...

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  • Hydrodynamic reanalysis of ice conditions in the Baltic Sea using the PM3D model

    The dataset contains the results of numerical modeling of sea ice in the Baltic Sea since 1998. A long-term reanalysis was performed using the three-dimensional hydrodynamic model PM3D (Kowalewski and Kowalewska-Kalkowska, 2017), a new version of the M3D model (Kowalewski, 1997). A numerical dynamic-thermodynamic model of sea ice (Herman et al. 2011)...

  • Evolutionary Sets of Safe Ship Trajectories: simulation results

    Publication

    The Evolutionary Sets of Safe Ship Trajectories is a method solving multi-ship encounter situations. For given positions and motion parameters the method finds a near optimal set of safe trajectories of all ships involved in an encounter. The paper briefly presents foundations of the method and focuses on simulation results for selected test cases based on the Baltic Basin. The computer simulations cover both open waters and restricted...

  • Improving the prediction of biochar production from various biomass sources through the implementation of eXplainable machine learning approaches

    Publication
    • V. G. Nguyen
    • P. Sharma
    • Ü. Ağbulut
    • H. S. Le
    • D. N. Cao
    • M. Dzida
    • S. M. Osman
    • H. C. Le
    • V. D. Tran

    - International Journal of Green Energy - Year 2024

    Examining the game-changing possibilities of explainable machine learning techniques, this study explores the fast-growing area of biochar production prediction. The paper demonstrates how recent advances in sensitivity analysis methodology, optimization of training hyperparameters, and state-of-the-art ensemble techniques have greatly simplified and enhanced the forecasting of biochar output and composition from various biomass...

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  • Restrained differential of a graph

    Publication

    - Discussiones Mathematicae Graph Theory - Year 2023

    Given a graph $G=(V(G), E(G))$ and a vertex $v\in V(G)$, the {open neighbourhood} of $v$ is defined to be $N(v)=\{u\in V(G) :\, uv\in E(G)\}$. The {external neighbourhood} of a set $S\subseteq V(G)$ is defined as $S_e=\left(\cup_{v\in S}N(v)\right)\setminus S$, while the \emph{restrained external neighbourhood} of $S$ is defined as $S_r=\{v\in S_e : N(v)\cap S_e\neq \varnothing\}$. The restrained differential of a graph $G$ is...

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  • Dimensional Synthesis of Coupled-Resonator Pseudoelliptic Microwave Bandpass Filters with Constant and Dispersive Couplings

    In this paper, we propose a novel technique for the dimensional synthesis of coupled-resonator pseudoelliptic microwave filters with constant and dispersive couplings. The proposed technique is based on numerical simulations of small structures, involving up to two adjacent resonators, and it accounts for a loading effect from other resonators by replacing them with terminations coupled through appropriately scaled inverters. The...

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  • Time for temporariness! Temporary architecture - whim or necessity?

    Publication

    - Year 2016

    What are the qualities of temporary architectural objects that make them helpful instruments for evolving the image of contemporary urban space? Six hypotheses provide rationales for why current temporary architecture seems to be a remedy for dysfunctional city structures. The research was limited to the temporary architectural objects constructed in open-air city zones, including the architecture of events. The temporary objects'...

  • Evolutionary Sets of Safe Ship Trajectories Within Traffic Separation Schemes

    Publication

    The paper presents the continuation of the author's research on Evolutionary Sets of Safe Ship Trajectories (ESoSST) methodology. In an earlier paper (Szlapczynski, 2011) the author described the foundations of this methodology, which used Evolutionary Algorithms (EA) to search for an optimal set of safe trajectories for all the ships involved in an encounter. The methodology was originally designed for open waters or restricted...

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  • Bridging challenges of clinical decision support systems with a semantic approach. A case study on breast cancer

    Publication

    - PATTERN RECOGNITION LETTERS - Year 2013

    The integration of Clinical Decision Support Systems (CDSS) in nowadays clinical environments has not been fully achieved yet. Although numerous approaches and technologies have been proposed since 1960, there are still open gaps that need to be bridged. In this work we present advances from the established state of the art, overcoming some of the most notorious reported difficulties in: (i) automating CDSS, (ii) clinical workflow...

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  • Modified GAPI (MoGAPI) Tool and Software for the Assessment of Method Greenness: Case Studies and Applications

    Publication

    - Analytica - Year 2024

    The green analytical procedure index (GAPI) has been widely used to assess the greenness of different steps in analytical methodology. In the GAPI index, the different stages of the chemical analysis process are depicted using five pentagrams divided in subsections, labeled green, yellow, or red according to the degree of greenness. This GAPI tool provides a quick overview of the environmental impact and safety of the procedure....

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  • Ultra-Compact Self-Quadruplexing Microfluidically Frequency Reconfigurable Slot Antenna Using Half-Mode SIW

    In this brief, the design of an ultra-compact self-quadruplexing frequency reconfigurable antenna (SQFRA) utilizing a half-mode substrate-integrated waveguide (HMSIW) and microfluidic channels is discussed. Four HMSIW cavities fed by four microstrip lines and slots are used to construct a highly compact antenna. The microstrip feedings to the HMSIW cavities are applied in such a way that the proposed antenna exhibits self-quadruplexing...

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  • Blue applicability grade index (BAGI) and software: a new tool for the evaluation of method practicality

    Publication

    - GREEN CHEMISTRY - Year 2023

    In this work, blue applicability grade index (BAGI) is proposed as a new metric tool for evaluating the practicality of an analytical method. BAGI can be considered complementary to the well-established green metrics, and it is mainly focused on the practical aspects of White Analytical Chemistry. This tool evaluates ten main attributes including the type of analysis, the number of analytes that are simultaneously determined, the...

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  • Student Perspectives on the 2017 ESA Concurrent Engineering Challenge

    Publication
    • K. Doerksen
    • T. van‘t Klooster
    • W. Ferguson
    • S. Pepper
    • D. van Paridon
    • R. Amorim
    • R. Chotalal
    • K. Ciechowska
    • A. Dąbrowski
    • V. Kunbrger... and 4 others

    - Year 2018

    In September 2017, the first ESA Academy’s Concurrent Engineering Challenge (CEC) was held, giving 88 Master’s and PhD-level students from twelve ESA Member and Associate States a powerful platform to experience system engineering in an intense, fast paced, and real-world environment. Within four days, teams of physics and engineering students in Concurrent Design Facilities (CDF) located in Politecnico di Torino, Universidad Polit´ecnica...

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