1. The external bias-dependent electric field at hole-injecting electrode/[alpha]-NPD junction and its relationship to Gaussian disordered interface statesBruno Cvikl, 2019, original scientific article Abstract: An alternative interpretation of two different sets of published temperature-dependent current-voltage a-NPD (i.e. N,N'-Di(1-naphthyl)-N,N'-diphenyl-(1,11-biphenyl)-4,4'-diamine) organic semiconductor data is presented. The measurements are described in terms of the hole drift current density expressed with two parameters: the electric field at the hole-injecting interface, Eint, and, ?max, the hole mobility determined by the measured current density at the maximum value of the externally applied electric field, Ea, in a given experiment. The former parameter, depending on the contact résistance, may be a function of Ea but the latter is Ea independent, The fixed value of Eint signifies the occurrence of the space charge limited current, SCLC, within the electrode/a-NPD structures and the contact is ohmic. Then, the calculated weak bias-dependent hole drift mobility, a function of Eint, equals the well%known exponential bias-dependent mobility, and saturates. The data not displaying SCLC characteristics are used for the calculation of Eint dependence on the applied field, Ea. It is shown that the quasi-ohmic contacts cause Eint to become a strong double-valued function of the externally applied electric field, Ea, described in terms of the distorted, inverted, high order parabola. The corresponding bias-dependent hole drift mobility is non-exponential and evolves on a considerably lower level than in SCLC cases. It is found that a sufficiently increased Ea alters the quasi-ohmic contact/a-NPD region into the ohmic one. A simple model of a thin, net hole charged, electrode/a-NPD interface enables the relationship between the deduced interfacial electric field, Eint, and the Ea dependent Gaussian width, as well as the energy shift of its peak along the negative binding energy is to be investigated. The currentvoltage method appears to be a helpful expedient for the investigation of the electric field at hole-injecting electrode/organic interfaces. Keywords: electrode/organic electric field, contact affected hole mobility, organic interface disorder parameters Published in DKUM: 22.12.2023; Views: 572; Downloads: 7 Full text (1004,22 KB) This document has many files! More... |
2. Determination of produced and consumed electricity of a residential building using a graphical user interfaceEva Simonič, Iztok Brinovar, Sebastijan Seme, Klemen Sredenšek, 2021, professional article Abstract: The primary objective of this paper is to present a graphical user interface for the calculation of electricity produced by a photovoltaic system and electricity consumed by a heat pump. The produced electricity is determined by a multi-year average of measurements of the global and diffuse power density of solar radiation for several places in Slovenia, while consumed electricity is determined based on the required heat for heating a residential building and domestic water. The calculation of produced and consumed electricity is validated by measurements on a real system. The developed graphical user interface enables simple user inputs of the photovoltaic system, heat pump, and the considered residential building, and provides a comprehensive technical analysis for installing both systems at the same location. Keywords: graphical user interface, photovoltaic system, heat pump, production of electricity, consumption of electricity Published in DKUM: 13.11.2023; Views: 278; Downloads: 13 Full text (2,75 MB) This document has many files! More... |
3. User Experience and Interface Design for a Digital Platform to Support Pet Adoption From Animal Shelters and Animal Rescue Organisations in Europe : magistrsko deloŠpela Bricman, 2023, master's thesis Abstract: This thesis used design thinking to create a user-friendly digital platform named PetScout for adopting animals from European shelters and rescue groups. We conducted user interviews and an online survey and designed personas, empathy maps, and scenarios to understand user needs. As part of the design process, we defined the platform’s requirements and developed the information architecture. We identified two viable solutions for the project based on research findings: a web-based and a mobile-based solution. To visualize these ideas effectively, we developed prototypes at two different fidelities – low and high fidelity. The prototypes were tested in usability testing using the thinking-aloud method, which measured effectiveness, efficiency, and satisfaction. The usability testing results showed that our platform is visually appealing, user-friendly, intuitive, and easy to use. A vital finding was the platform’s effectiveness, as high-fidelity prototypes achieved a task completion rate of 100%. Moreover, the concept proved highly efficient since participants, on average, needed 166 seconds to finish vital tasks. Additionally, the SUS score of 97, supported by the positive qualitative user feedback, signifies outstanding user satisfaction and a high level of usability. Finally, this study highlights the importance of knowing and understanding user needs in design, and it provides recommendations to improve usability and potentially increase the number of successful adoptions on similar platforms. Keywords: user experience design, user interface design, design thinking, user research, usability testing Published in DKUM: 13.10.2023; Views: 505; Downloads: 36 Full text (7,91 MB) |
4. User Experience of Croatian National & Nature Parks’ Website – A Comparison : a comparisonMihaela Franjić, 2022, master's thesis Abstract: We are not saying that tourism is a dynamic area for no reason, as the COVID–19 pandemic has shown us. Tourism is influenced by many external factors, and one of them is the development of digital technology, which must be monitored in parallel. We are currently in a historical period that is characterized by the fact that without the Internet there is no expansion into other markets. Digital technology covers all pores and activities of modern society, enables new ways for sales, development, distribution in the tourist market, which is full of opportunities and obstacles. Websites have evolved largely because they help, especially small and medium–sized organizations reduce costs, time, and help them market and present themselves to users.
In this paper, we will deal with Croatian national and natural parks, which are a national treasure of exceptional importance for Croatian tourism, and which annually attract around 3.5 million tourists. For the first time, in 2017, the parks of Croatia integrated all the parks on one website through the PARCS project, as a basis for better informing users and promoting the parks as a brand on the tourist market. Precisely for this reason, we are interested in how users view the website www.parkovihrvatske.hr, since the appearance of the site has not been renewed since 2017. It is extremely important to know the opinion of potential users, because more than half of the time they plan and book their trip via the Internet with the help of a computer. This is one more reason to check the current situation and opinion of foreign and domestic citizens. The research enabled us to compare respondents, connect expectations and evaluations, and at the end provide an additional opinion of the respondents. In order to improve and improve the user experience according to the respondents, the website should work on its design, security, include all park offers together with tickets and update its information. Based on the analysis, we will try to present guidelines for upgrading the website if they want to be trendy, competitive and expand into the tourist market overwhelmed by digital transformation. Keywords: Digital Tourism, Digital Transformation, User Interface, User Experience, Croatian National and Natural parks Published in DKUM: 24.10.2022; Views: 828; Downloads: 138 Full text (3,09 MB) |
5. AI for optimizing analog RF parameters on NFC frontends : magistrsko deloMatej Žnidarič, 2022, master's thesis Abstract: In this Master’s thesis, we study in detail NFC technology, NFC standardization, Artificial intelligence and GUI topics.Our goal is to optimize the measurement process of the FeliCa listener phase window in order to define the best analog parameters for the NFC IC. Namely, by combining machine learning and test automation, we want to achieve a faster validation time of the NFC IC under test. Firstly, we introduce the main topics related to NFC and present the thesis alongside specific goals. Next, we present the NFC technology on a fewuse cases. We also cover international standards, emphasizing sections that directly affect our validation and, therefore, the understanding of our solution. The NFC coverage is described alongside data representation used to interpret data used in proprietary software. Artificial intelligence is integrated into this software for multidimensional data interpolation task. We also cover the basics of deep neural networks and the most common architectures used in the DL field. The neural network training process is also covered to understand how we can optimize neural network global minimum convergence. In the last part of the thesis, we also explain how proprietary software tool actually works and how it can outperform previous processes. In the end, specific solutions related to the tool are described in more detail to understand our software development decisions better. Finally, we present measurement results and evaluate our goals. Keywords: NFC wireless communication, artificial intelligence, test coverage, FeliCa, graphical user interface, analog parameter extraction Published in DKUM: 08.06.2022; Views: 1172; Downloads: 0 |
6. Implementation and verification of a geosynthetic-soil interface constitutive model in the Geogrid element of FLAC$^{3D}$Wu Haimin, Shu Yiming, Dai Linjun, Teng Zhaoming, 2015, original scientific article Abstract: Due to the complexity of geosynthetic-soil interactions, the simple interface constitutive models embedded in the geosynthetic elements of general computing software cannot satisfy the requirements for a numerical simulation of different geosynthetic-soil interface behaviours. Based on the direct shear test results of a composite geomembrane (CGM) and polyurethane (PUR) mixed crushed stones interface, a nonlinear elastic, perfectly plastic model was used to describe the interface behaviours. The method of incorporating an interface constitutive model into the Geogrid element of a fast Lagrange analysis of continua in three dimensions (FLAC3D) procedure was presented in detail through a user-defined program in the FISH environment. Then the incorporated model of the Geogrid element was used to simulate the direct tests of the CGM-PUR mixed crushed stones interface. The results of the numerical tests confirmed the validity and reliability of the incorporated model. The method and program flowchart for implementing the nonlinear elastic, perfectly plastic interface constitutive model into the Geogrid element can provide a reference for users who want to simulate other geosynthetic-soil interface behaviours with FLAC3D. Keywords: geosynthetic-soil interface, constitutive model, numerical modelling, FLAC3D, geogrid element Published in DKUM: 14.06.2018; Views: 1558; Downloads: 74 Full text (269,05 KB) This document has many files! More... |
7. The Bosnian-Croatian-Serbian adnominal possessive dative at the syntax-pragmatics interfaceJames Joshua Pennington, 2012, original scientific article Abstract: In Bosnian, Croatian, and Serbian, the adnominal possessive dative (APD) construction is used alongside the nominal adjectival construction to express possession. APD usage is double-edged – i.e., there are both issues of sociolinguistics/perceptual dialectology involved as well as more formal syntactic- pragmatic ones. My respondents consistently labeled APD usage as “archaic,” “old-fashioned,” “characteristic of the uneducated,” or “country-talk”. However, judging by very similar acceptance levels of APDs in particular contexts in all dialects, it appears that semantic role of the possessor and the level of contextual effects and processing load involved in interpreting possessive constructions weigh heavily on their acceptance. Therefore, I offer a model that attempts to capture APD usage in terms of a set of hierarchical relationships between the “possessor” and the “possessed”. Keywords: sociolinguistics, adnominal possessive dative, perceptual dialectology, dialect geography, syntax-pragmatic interface Published in DKUM: 13.02.2018; Views: 1371; Downloads: 433 Full text (805,16 KB) This document has many files! More... |
8. Vpliv uporabnika na spletno marketinško platformoSlavica Šuman, 2017, master's thesis Abstract: As a part of the Master thesis, we wanted to improve user experience, user interface and usability of Forsikringsportalen platform. Based on literature review and case studies conducted from the same or similar area of research, we redesigned certain elements of the platform. The performance of the redesigned elements was measured with Preference and Question tests as well as gathering of statistical data. With gathered results, we formed a conclusion that will help the company to engage users more. With the implemented improvements and increased percentage of first-time logins, the company can focus on the engagement after the login. Keywords: Forsikringsportalen, usability, user experience, user interface, online platform Published in DKUM: 06.10.2017; Views: 1759; Downloads: 47 Full text (3,87 MB) |
9. Materials design for language m-learningDejan Pukšič, Melita Zemljak Jontes, Marjan Krašna, 2015, original scientific article Abstract: Today's smart phones are versatile multimedia devices. Their processing power is incredible compared to decades-old personal computers (PCs), and the time is right to use them in education. The touch screen has provided a haptic user interface that cannot be considered as merely another mouse. The design of m-learning materials therefore needs to follow a special set of rules to maximize the efficiency of constraints posed by the devices and the user interface. In the article the design considerations are presented in the context of a practical application for using mobile devices in language learning with the application BlaBla$^{TM}$. Keywords: m-learning, design, mobile assisted language learning, haptic user interface Published in DKUM: 21.09.2017; Views: 1358; Downloads: 160 Full text (729,26 KB) This document has many files! More... |
10. EFFECT OF GELATINE SCAFFOLDS FABRICATION AS POLYPROPYLENE MESH COAT ON IMPLANT BIOCOMPATIBILITYSelestina Gorgieva, 2014, doctoral dissertation Abstract: This work presents the methodological study, processing and optimization of novel, technologically acceptable procedure for in situ coating of polypropylene (PP) mesh (used for hernia treatment) with physico-chemically, mechanically and micro-structurally different gelatin (GEL) scaffolds to assess implant composite biocompatibility impact. In order to systematically follow the experimental work progress and respective achievements, whole research path is subdivided into three main sections.
In the first section, the procedure for fabrication of gradiently micro-porous GELscaffolds on the cryo-unit’s cooling plate surface, using spatiotemporal and temperature- controlled gelation and freezing, followed by lyophylizaton was studied. Subsequently, cross-linking procedure using different molarities of reagents (EDC and NHS) and reaction media (100% PBS or 20/80% PBS/EtOH mixture) was performed for variable time extensions (1-24 h), rendering scaffolds physico-chemical properties. In this way, scaffolds with micro-structures having porosity gradient from 100 µm to 1000 µm and pores with rounded to ellipsoid morphology were formed, which, in combination with ethanol (EtOH) addition in cross-linking media modulates the swelling capacity towards twice lower percentages (~600%) comparing with scaffolds cross-linked in 100% PBS. Whilst the presence of EtOH reduce the cross-linking kinetic by retaining the scaffolds’ micro-structure formed during freezing, the 100% PBS and higher EDC molarity resulted in 40% cross-linking degree, being expressed as a thermal resistance up to 73 °C. The presented integral fabrication procedure was shown to allow tuning of both, the physical and micro-structural properties of scaffold, utilized in preparation of materials for specific biomedical applications.
In the second part, the complex relation between surface and interface-related physico-chemical properties and gradient micro-structuring of 3D GELscaffolds, being fabricated by simultaneous temperature- controlled freeze-thawing cycles and in situ cross-linking using variable conditions (pH and molarity of carbodiimide reagent) and fibroblast cells viability (by tracking of their spreading and morphology) was established. Rarely- populated cells with rounded morphology and small elongations were observed on scaffolds with apparently negatively- charged surface with a lower cross-linking degree (CD) and consequently higher molecular mobility and availability of cell-recognition sequences, in comparison with the prominently- elongated and densely- populated cells on a scaffold’s with positively- charged surface, higher CD and lower mobility. Surface micro-structure effect was demonstrated by cell’s vacuolization and their pure inter-communication being present on scaffold’s bottom side with smaller pores (25±19 µm) and thinner pore walls (9±5 µm), over the air- exposed side with twice bigger pores (56±38 µm) and slightly thicker pore walls (12±6 µm). Strong correlation of preparation conditions (pH and reagents molarity) with CD (r2=0.96) and moderate correlation with local molecular mobility (r2 =-0.44), as well as micro-structure features being related to temperature gradient, imply on possibility to modulate scaffold’s properties in a direction to guide cell’s viability and most likely its genotype development.
The third part presents an innovative strategy for the fabrication of bio-active PPmesh-GELscaffold composites with a potential for abdominal hernia treatment, where mesothelial cells in-growth have to be stimulated together with fibroblasts on-site proliferation, while formation of fibrin-developing, viscera-to-abdominal wall adhesions should be reduced, together with bacteria- related infections. In this respect, the plasma pre-activated PPmesh was coated with micro-structured GELscaffold, with pore size in 50 µm to 100 µm range at the upper-side and loosely- porous network at the composite bottom side, being modulated by sample thickness and freezing end- temperature applied. Simultaneously, the Keywords: gelatin, targeted cross-linking, controlled freezing, gradiental micro-porosity, scaffold, surface and interface chemistry, physico-mechanical properties, polypropylene mesh, composite, biocompatibility. Published in DKUM: 07.05.2014; Views: 2355; Downloads: 177 Full text (4,98 MB) |