Neste trabalho, estudamos o problema de corte bidimensional multiperíodo com sobras aproveitáveis, que consiste em cortar objetos grandes visando a produção de um conjunto de itens menores. Supomos um horizonte de planejamento finito com uma quantidade finita de períodos entre os tempos inicial e final. Primeiramente consideramos uma versão determinística em que conhecemos, à priori, os itens solicitados em uma ordem de trabalho e o custo dos objetos a cada período. Algumas das sobras geradas durante o processo de corte dos itens solicitados em um período podem ser utilizadas como objetos no futuro. As sobras que podem ser usadas no futuro são denominadas sobras aproveitáveis. De forma geral, uma sobra é considerada aproveitável se possui dimensões iguais ou superiores as de algum item de uma lista pré-definida para o período. O objetivo é minimizar o custo total dos objetos utilizados para satisfazer a ordem de trabalho dos itens solicitados de todo o horizonte considerado. Havendo soluções com o mesmo custo, desejamos encontrar aquela que, no fim do horizonte de tempo considerado, maximize o valor das sobras aproveitáveis remanescentes. Apresentamos uma modelagem matemática do problema usando uma formulação em dois níveis, que é transformada em um modelo de programação linear inteira mista, devido às características do problema. Considerando a dificuldade em resolver o modelo desenvolvido, apresentamos uma proposta de uma abordagem heurística baseada em Programação Dinâmica Aproximada (PDA) para lidar com o problema proposto. Outras opções baseadas em estratégias do tipo horizonte rolante e relax-and-fix também são consideradas. Consideramos também o cenário onde não conhecemos de antemão os itens da ordem de trabalho e o custo dos objetos, mas temos informações das distribuições de probabilidade de ambos. Nesse caso, apresentamos uma abordagem baseada em programação dinâmica aproximada para estimar a melhor estratégia a ser seguida em cada período. Comparamos os resultados obtidos pela PDA com os resultados encontrados por um método guloso. Em cenários adequados, os resultados mostram que a PDA consegue soluções superiores ao método guloso. / In this research, we study the multi-period two-dimensional cutting problem with usable leftover, which consists of cutting objects to produce a set of items. We assume a finite planning horizon with a finite amount of periods between the initial and final times. First we consider a deterministic version in which we know, a priori, the set of ordered items and the cost of the objects at each period. Some of the leftovers generated during the cutting process of the ordered items in a period may be used as objects in the future. The leftovers that can be used in the future are called usable leftovers. In general, a leftover is considered usable if it has dimensions equal to or greater than that of some item from a predefined list for the period. The goal is to minimize the total cost of the objects used to cut the set of ordered items of the entire considered horizon. If there are solutions with the same cost, we wish to find one that, at the end of the considered time horizon, maximizes the value of the remaining usable leftovers. We present a mathematical model of the problem using a bilevel formulation, which is transformed into a mixed integer linear programming model, due to the characteristics of the problem. Considering the difficulty in solving the developed model, we propose a heuristic approach based on approximate dynamic programming (ADP) to deal with the proposed problem. Other options based on the rolling horizon and relax-and-fix strategies are also considered. We also consider the scenario where we do not know in advance the set of ordered items and the cost of the objects, but we have information about the probability distributions of both. In this case, we present an approach based on approximate dynamic programming to estimate the best strategy to be followed at each period. We compared the results obtained by the ADP with the results found by a greedy method. In suitable scenarios, the results show that the ADP achieves superior solutions to the greedy method.

Personal data is often disclosed with every registration, sharing, or request of an online service. With the increased usage of things connected to the Internet, users' information being collected and stored, the risks related to unknowingly sharing personal data increases. Sharing of personal information is a sensitive subject and can hurt people’s assets, dignity, personal integrity and other social aspects. In general, users’ concerns have grown regarding protecting their personal information which has led to the development of multiple privacy-oriented systems. In scenarios where users are logging onto a website or system, they rarely notice, understand or have desire to read the conditions to which they are implicitly agreeing. These systems are often referred to as identity management systems or single sign-on systems. Recent studies have shown that users are not aware of what data transactions take place by using various authentication solutions. It is critical for these types of system dealing with privacy that researchers examine users' understanding of the concepts through interface design. The purpose of this study is to investigate the usability and user awareness of data transactions for identity management systems on mobile devices by constructing and evaluating different design concepts. Therefore, four different mobile prototypes were designed (called CREDENTIAL Wallet) and explored to measure the usability and also the user awareness of users’ disclosures. 20 usability tests were conducted per prototype. Multiple conclusions can be drawn from this study. The findings showed that the drag-and-drop prototype scored a high user awareness score in terms of participants remembering their shared data and having a good idea of them not sharing more data than they had actually shared. Consequently, the drag-and-drop prototype achieved the highest usability result. A prototype that utilized swiping was created to fit the mobile medium. The prototype showed the highest user awareness score in the context of participants stating what data they had shared. However, people using the swiping prototype thought they were sharing more data than they actually were. Data show that users have an incorrect mental model of the sharing of their fingerprint pattern. Finally, the writing concerns recommendations and challenges of identity management systems – e.g. the importance of tutorial screens. Future studies within the CREDENTIAL project are already underway concerning users' incorrect mental model of sharing fingerprint to the service provider side. / CREDENTIAL

The diploma thesis addresses the influence of building work carried out on the family house and the comparison of this influence in various localities. The theoretical part defines the basic terms from professional literature and legislation. A family house prior to reconstruction in the town of Bolera-dice was selected and then two other similar sites of the municipality of Hostěradice and the town of Koryčany. In the practical part, the customary prices were calculated before reconstruction. The reconstruction of the house was projected and the costs of construction work were calculated using an itemised budget. By means of a database of real estate properties after reconstruction, the prices of similar real estate properties after the reconstruction were established. The conclusion of the the-sis presents a comparison and analysis of the results at individual sites, and thus fulfils the objective of the thesis by determining the impact of construction work on the family house and comparing this in different locations.

This master´s thesis is focused on detterminations of the difference between the standard price of a detached passive house and selected detached houses in Chomutov and its surroundings. The theoretical part of the thesis describes the basic terms used in real estate valuation. The main task of this thesis is in Chomutov establish the standard price of houses with regard to their implementation, to evaluate land forming their accessories and assess standart value house without land, in order to eliminate the influence of land price to the price of the property. For valuation has been selected 10 houses from the Ústecký kraj of 3 districts (Chomutov, Louny and Most).

The object of thesis is estimation of the normal price for property type of apartment in Hradec Králové, including finding of the extent to which is the normal price influenced by the type of supporting structure. A partial task is valuation of selected apartments using different valuation methods. The solution task were used the price regulation methods – cost method and comparative method and market valuation methods – yield method and the direct comparison method of valuation, which is estimated market value. Finally the thesis contain a recapitulation of prices and analysis of detected differences.

The study aims to investigate the current process for vacation exchange at Karlstad municipality to elicit system requirements for a future system. The investigation includes creating an understanding of the vacation exchange process, the roles involved, and their tasks performed in the process. Further, the limitations, the information used, and the decisions made in the vacation exchange process were also a part of the investigation. The investigation of the vacation exchange process is performed by analyzing an internal document from Karlstad municipality and interviews conducted with the three roles involved in the process. The interviews are transcribed, summarized, and modeled by process models using 2c8 Modeling Tool to explain the vacation exchange process, inputs, and outputs, and the tasks each role performs. The findings showed three specific categories in the vacation exchange process that should be improved when a future system is designed and developed to support the process. The three found categories were: lack of information, information flow, and distribution of responsibilities. In conclusion, the future system should have a function to notify the roles involved. Information used in the vacation exchange process should be gathered and easily accessible in the future system. Further, the future system should support communication between the roles involved in the vacation exchange process, as well as include functions for back-up, digital sending of documents, and facilitate rarely performed tasks. Lastly, the future system should define the responsibilities for each role to balance the tasks each role performs in the process.

<p dir="ltr">This thesis details the development of a multidisciplinary design analysis (MDA) framework intended to evaluate a rocket-powered, reusable hypersonic vehicle. In particular, the analysis framework computes the design closure of a coupled system resembling Stratolaunch Systems’ Talon-A reusable hypersonic test vehicle. The resulting analysis framework differs from available literature due to its focus upon payload-related design considerations. The presented framework, too, avoids the use of proprietary technical information and/or export-controlled analysis tools. The framework’s geometric analysis, for example, employs a reverse-engineered geometry resembling Talon-A. An open-source aerothermal package, too, was selected to evaluate the vehicle’s aerothermodynamic characteristics. Quick-to-implement methods were prioritized to expedite the development of the MDA framework. Notably, a regression-based structural analysis model was used, as well as an interpolative thermal protection system (TPS) sizing procedure. A quasi-steady trajectory model, too, was implemented within the MDA framework, to determine the vehicle’s mission performance. The resulting analysis takes the form of a six-discipline MDA framework that can calculate, among other parameters, the vehicle’s cruise duration. Initial design closure results for a vehicle resembling Talon-A, using an assumed TPS size, are currently available. These results report an estimated total vehicle mass within thirty percent of Talon-A’s true gross mass, as well as a cruise duration of approximately 445 seconds. These design closure results were also evaluated under a perturbed specific impulse of ±10%, with a resulting change in cruise duration of ±12.3%. Results for a cruise-condition design exploration procedure were also obtained within a simplified, sequential analysis chain. These design exploration results report a maximum cruise lift-to-drag ratio of approximately four. Future work has been identified, too, including the integration of more rigorous analysis tools for use within future iterations of the MDA framework. Notably, these tools include an open-source optimal control library, as well as a physics-based TPS sizing tool</p>

A key challenge of the learning sciences is moving research results into practice. Educators on the front lines perceive little value in the outputs of education research and demand more “usable knowledge”. This work explores the potential instead of usable artifacts to translate knowledge into practice, adding scientists as stakeholders in an interaction design process. The contributions are two effective systems, the scientific and contextual principles in their design, and a research model for scientific research through interaction design. College student study practices are the domain chosen for the development of these methods. Iterative ethnographic fieldwork identified two systems that would be likely to advance both learning in practice and knowledge for applying the employed theories in general. Nudge was designed to improve students’ study time management by regularly emailing students with explicit recommended study activities. It reconceptualizes the syllabus into an interactive guide that fits into modern students' attention streams. Examplify was designed to improve how students learn from worked example problems by modularizing them into steps and scaffolding their metacognitive behaviors though problem-solving and self-explanation prompts. It combines these techniques in a way that is exceedingly easy to author, using existing answer keys and students' self-evaluations. Nudge and Examplify were evaluated experimentally over a full semester of a lecture-based introductory chemistry course. Nudge messages increased students’ sense of achievement and interacted with students’ existing time management skills to improve exam grades for poorer students. Among students who could choose whether to receive them, 80% did. Students with access to Examplify had higher exam scores (d=0.26), especially on delayed measures of learning (d=0.40). A key design decision in Examplify was not clearly resolvable by existing theory and so was tested experimentally by comparing two variants, one without prompts to solve the steps. The variant without problem solving was less effective (d=0.77) and less used, while usage rates of the variant with problem solving increased over time. These results support the use of the design methods employed and provide specific empirical recommendations for future designs of these and similar systems for implementing theory in practice.

The proliferation of the internet and associated online activities exposes users to numerous information security (InfoSec) threats. Such online activities attract a variety of online users who include novice computer users with no basic InfoSec awareness knowledge. Information systems that collect and use sensitive and confidential personal information of users need to provide reliable protection mechanisms to safeguard this information. Given the constant user involvement in these systems and the notion of users being the weakest link in the InfoSec chain, technical solutions alone are insufficient. The usability of online InfoSec systems can play an integral role in making sure that users use the applications effectively, thereby improving the overall security of the applications. The development of online InfoSec systems calls for addressing the InfoSec problem as a social problem, and such development must seek to find a balance between technical and social aspects. The research addressed the problem of usable security in online InfoSec applications by using an approach that enabled the consideration of both InfoSec and usability in viewing the system as a socio-technical system with technical and social sub-systems. Therefore, the research proposed a socio-technical framework that promotes the development of usable security for online information systems using online banking as a case study. Using a convergent mixed methods research (MMR) design, the research collected data from online banking users through a survey and obtained the views of online banking developers through unstructured interviews. The findings from the two research methods contributed to the selection of 12 usable security design principles proposed in the sociotechnical information security (STInfoSec) framework. The research contributed to online InfoSec systems theory by developing a validated STInfoSec framework that went through an evaluation process by seven field experts. Although intended for online banking, the framework can be applied to other similar online InfoSec applications, with minimum adaptation. The STInfoSec framework provides checklist items that allow for easy application during the development process. The checklist items can also be used to evaluate existing online banking websites to identify possible usable security problems. / Computer Science / D. Phil. (Computer Science)

Användbarhet är en term som används för att bedöma kvaliteten hos ett gränssnitt. God användbarhet är viktig då den ger en ökad produktivitet och andra affärsfördelar i form av färre misstag och bättre kvalitet på slutprodukten. Användbarhet är en viktig designprincip men är en svår egenskap att uppfylla hos applikationer. Studien behandlar användbarhet ur olika perspektiv, dels det teoretiska genom litteraturgenomgång, dels det praktiska genom intervjuer och observationer. Syftet var att förklara vad användbarhet är, hur det bedöms och vad man kan göra för att bygga in egenskapen i applikationer man utvecklar. För att exemplifiera och finna verklig förankring har jag valt att observera hur användare interagerar med ett existerande gränssnitt för bibliotek, Horizon. Slutsatser kring studien är att Horizon inte används till allt den var tänkt att användas till, vilket i princip är ett dåligt betyg för en applikation. Samtidigt är detta inget större problem då den negativa verkan på verksamheten kan i det här fallet vara en definitionsfråga: är studenternas produktivitet när det gäller att söka och beställa litteratur kritisk? När det gäller användbarhet i utvecklingsskedet kan man konstatera att även om intentionerna varit goda så har användbarhetsarbetet kring Horizon inte infriat förväntningarna. Vad som gått fel är varken sensationellt eller ovanligt; det har handlat om avsaknaden av slutanvändarens perspektiv, organisatoriska problem och möjligen också bristande kunskap om användbarhet i en eller annan form. En betydelsefull insikt som inte nämns i litteraturen men som togs upp är att beakta leverantörens marknadsställning när man ska köpa ett system. Trots bristerna, som ofta relaterar till brott mot designkonventioner, upplevs Horizon som ett bra och ändamålsenligt verktyg av sina användare. / Usability denotes the quality of a user interface. Even though usability is an important design principle, efforts to incorporate this quality in applications often fail. In this paper I study usability from a theoretical and a practical perspective. The goal is to explain usability and how to incorporate usability in applications. In order to exemplify, I study usability within the context of the library application Horizon. This study shows that Horizon is only partially utilized by its users which in principle is a bad grade for an application. Partial use is however in this case, not a serious problem since the negative effects partial use imply could very well be a matter of definition: is the productivity of students, when it comes to searching and ordering library material, critical for the organization? When it comes to usability in the development phases of a project, once again one can conclude that good intentions exist but efforts fail all the same and Horizon is no exception. This time we can attribute failure to the lack of the end users’ perspective, organizational problems and perhaps also unsufficient knowledge of usability in one form or another. An important conclusion, which has not been mentioned in the literature, is the importance of considering the market position of a presumptive vendor when buying a generic system. Despite the flaws (often related to violations of well established design principles) presented in this paper, Horizon is considered a good, effective and efficient application by its users.