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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
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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
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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
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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
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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: 178
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