The Professor's Cube is the 5×5×5 variant of the Rubik's Cube. The reduction method sets the Professor's Cube in a state where the problem of solving it is reduced to the problem of solving the Rubik's Cube. Two variations of the reduction method were compared to see which reduces the Professor's Cube in the fewest moves: one in which the edge pieces are assembled in the right orientation and one where they may be assembled in the wrong orientation and are later corrected. The results indicate that the former method is the more effective, but may not be reliable due to the implementation of the solver.

The purpose of this study was to investigate the efficiency of double-decked elevators in a skyscraper environment. This was done by simulating elevator activity using different elevator types and elevator control algorithms. The results gained from the simulation suggested that double-decked elevators always provide better performance over using regular single-decked elevators. Some control algorithms proved to have up to ten times better efficiency compared to others using double-decked elevators.

This thesis is aimed to cover how boolean satisfiability solvers can be used on integer factorization problems and to compare them with already established integer factorization solvers. The integer factorization problem is believed to be hard and is used in modern day cryptoalgorithms such as RSA. This thesis is also aimed to explore how well different solvers can solve different types of semiprimes and if there is any notable difference between them. This report covers three different boolean satisfiability solvers as well as three of the integer factorization solvers. The results from the thesis show that boolean satisfiability solvers cannot be used as a replacement of already established integer factorization solvers. The thesis also shows that the type of semiprime does affect how fast the solvers are able to factorize the semiprime. The boolean satisfiability solvers had favorable results toward asymmetrical semiprimes and disfavorable results toward prime powers. / Denna avhandlings mål är att undersöka hur lösare för booleska satisfierbarhetsproblemet kan användas för att lösa primtalsfaktoriseringsproblem och jämföra dem med redan etablerade lösare för primtalsfaktorisering. Primtalsfaktorisering tros vara svårt och används i flera moderna krypteringsalgoritmer som RSA. Denna avhandling undersöker även hur väl olika lösare kan lösa olika typer av semiprimtal och om det finns någon noterbar skillnad mellan dem. Rapporten täcker tre olika lösare för booleska satisfierbarhetsproblem och tre olika primtalsfaktoriseringslösare. Resultaten från denna avhandling visar att lösare för booleska satisfierbarhetsproblem inte kan används som ersättning för redan etablerade primtalsfaktoriseringslösare. Avhandlingen visar även att typen av semiprimtal påverkar hur snabbt lösarna faktoriserar semiprimtalet. Lösarna för boolesk satisfierbarhet visade fördelaktiga resultat mot asymmetriska semiprimtal och ofördelaktiga resultat mot primtalspotenser.

Rendering transparent geometry is problematic in real-time graphics as the most function for blending transparent geometry together requires perfect sorting of all geometry. This can be extremely problematic, especially for intersecting geometry where it might be impossible to correctly sort it. Therefore, a number of new algorithms that attempt to approximate or reproduce the result of sorted blending in an order-independent manner has been developed lately. Fourier Opacity Mapped Order-Independent Transparency (FOMOIT) is a new algorithm which constructs an approximated visibility function for each pixel and stores it using Fourier series. It then uses these functions to calculate a weighted sum of colors for each pixel. Neither the visibility function nor the weighted sum requires the geometry to be sorted. FOMOIT has better quality compared to Weighted Blended Order-Independent Transparency (WBOIT). Compared to Adaptive Order-Independent Transparency (AOIT), Fourier Opacity Mapped Order-Independent Transparency has a number of advantages. FOMOIT uses hardware functions that are more widely available, and can easily be tweaked to have better performance and memory usage at minimal quality loss. It can therefore be especially useful on older and/or weaker computers. FOMOIT suffers from a few limitations and artifacts in certain cases. The first problem lies in the dependence on a tight depth range of the scene. This makes FOMOIT unfit for certain types of real-time graphics that require a wide depth range. The second problem is self-occlusion of geometry, which can cause incorrect weights to be calculated, resulting in color bleeding. We propose a workaround for this problem, but further research is encouraged in this area. Our conclusion is that FOMOIT can, as long as the limitations of the algorithm are respected, produce higher quality results than AOIT while providing better hardware compatibility, performance and memory usage, and even in cases where AOIT provides better visual quality, FOMOIT can be used as a lower quality fallback for older and weaker computers.

Det arbete som har utförts under våren och sommaren 1999 på Siemens Elema och som behandlas i denna rapport, hade som mål att implementera säkerhetsfunktioner i ett dokumenthanteringssystem för patientjournaler. Arbetet baseras på ett testsystem bestående av en applet och en servlet som i princip hade samma funktionalitet som det tilltänkta dokumenthanteringssystemet (loggade in användare, hämtade en fil från server, möjliggjorde för användaren att ändra i filen och till slut sparade filen på servern). Följande säkerhetsfunktioner implementerades: - Säker inloggning med dubbel, stark autentisering med certifikatsystem. Inloggningsproceduren undviker att skicka användarens lösenord över nätet. - Säker, krypterad dataöverföring med SSL - Digitala signaturer som ger positivt bevis av att ett sparat dokument på servern har skickats in av en viss användare. Hela systemet implementerades i Java 1.2 med standardkomponenter, som är fritt tillgängliga utan kostnad.  Beslutet att använda Java 1.2 som utvecklingsplattform medförde att flera problem uppstod p.g.a. att säkerhetsfunktionaliteten i Java 1.2 (senare kallad Java 2) är relativt ny, oprövad och stödet för den är ännu inte fullt implementerat i de webbläsare som är mest vanliga (Netscape Communicator och InternetExplorer4). Dessa problem är delvis lösta eller kan kringgås och systemet kan nu installeras och köras på en vanlig PC, via en vanlig webbläsare. / The work carried out during the spring and summer of 1999 at Siemens Elema and covered in this report, aimed to implement security features in a document management system for patient records. The work is based on a test system consisting of an applet or a servlet which basically had the same functionality as the intended document management system (logged in users, downloaded a file from the server, allowing the user to modify the file, and finally saved the file on the server). The following features were implemented: - Secure login with double, strong authentication with certificate system. The logon procedure avoids sending the user's password over the network. - Secure, encrypted data transfer with SSL - Digital signatures that provide positive evidence of a saved document on the server are submitted by a particular user. The whole system was implemented in Java 1.2 with standard components, which is freely available at no cost. The decision to use Java 1.2 as development platform resulted in several problems arose due to security functions in Java 1.2 (later called Java 2) is relatively new, untested and the support for it is not yet fully implemented in the browsers that are most common (Netscape Communicator and InternetExplorer4). This problem is partly solved or can be circumvented and the system can now be installed and run on a standard PC, via a standard Web browser.

Rekursion inom SQL är ett relativt nytt begrepp som introducerades i standarden SQL:1999 eftersom man insåg att det fanns ett behov av att skriva mer kraftfulla frågor i SQL. De flesta som arbetar inom eller har kunskap om IT känner i stor utsträckning till SQL. Trots detta ansåg författarna av denna rapport att kunskapen inom området för rekursion var tämligen begränsad. I rapporten undersökts hur kraftfull rekursion inom SQL är genom att rekursionstyper först identifieras och sedan implementerats i SQL-satser vilka körts och prestanda mäts på körningarna. Detta gjordes med Postgresql, databasen vilken rapporten i stort fokuserar på. Huruvida samma möjligheter eller begränsningar existerar i andra implementationer av SQL undersöks inte i denna rapport.Undersökningen visar att endast linjär rekursion är möjligt att använda i Postgreqsls implementation, precis som det står definierat i SQL:1999. Detta i sig är en stor begränsning då icke-linjära rekursionsfrågor ej är möjliga att ställa. Undersökningen visar dessutom att det som kallas rekursion inom både Postgresql och SQL:1999 inte egentligen är riktig rekursion i den bemärkelse som programmerare normalt använder, utan är mer likt iteration som i t.ex. en while-loop. Prestandan i Postgresql visar sig vara mycket god på de mycket stora testfall som rapporten behandlar. Rapporten går även igenom vissa sätt att komma runt detta problem med, som exempelvis dynamisk programmering. Rapporten utvärderar även olika sätt att förhindra evig körning av rekursiva frågor, som t.ex. då en oändlig loop förhindrar att frågan termineras.

This essay expands on the problem of human attention detection in computer vision. This is achieved by providing a method for annotating existing face datasets with attention labels through the use of human intelligence. The work described in this essay is justified by a lack of human performance attention datasets and the potential uses of the developed method. Several images of crowds were generated using the Labeled Faces in the Wild dataset of images depicting faces. Thus enabling evaluation of the level of attention of the depicted subjects as part of a crowd. The data collection methodology was carefully designed to maximise reliability and usability of the resulting dataset. The crowd images were evaluated by workers on the crowdsourcing platform CrowdFlower, which yielded human performance attention labels. Analysis of the results showed that the submissions from workers on the crowdsourcing platform displayed a high level of consistency and reliability. Hence, the developed method, although not fully optimised, was deemed to be a valid process for creating a representation of human attention in a dataset. / Denna uppsats behandlar problemet med att upptäcka mänsklig uppmärksamhet, vilket är ett problem inom datorseende. För att göra framsteg mot att lösa problemet utvecklades en metod för att skapa uppmärksamhetsmärkningar till dataset av ansiktsbilder. Märkningarna utgör ett mått av den uppfattade uppmärksamhetsnivån hos personerna i bilderna. Arbetet i denna uppsats motiveras av avsaknaden av dataset med uppmärksamhetsmärkningar och den potentiella användbarheten av den framtagna metoden. Metoden konstruerades med fokus på att maximera tillförlitligheten och användbarheten av insamlad data och det resulterande datasetet. Som ett första steg i metodutvecklingen genererades bilder på folkmassor genom att använda datasetet Labeled Faces in the Wild. Evaluering av uppmärksamhetsnivån hos personerna i bilderna, som individer i en folkmassa, blev då möjligt. Denna egenskap utvärderades av arbetare på crowdsourcing-plattformen CrowdFlower. Svaren analyserades och kombinerades för att beräkna ett uppmärksamhetsmått med mänsklig prestanda för varje individ i bilderna. Resultatanalysen visade att svaren från arbetarna på CrowdFlower var tillförlitliga med hög intern konsistens. Den framtagna metoden ansågs vara ett giltigt tillvägagångssätt för att skapa uppmärksamhetsmärkningar. Möjliga förbättringar identifierades i flera delar av metoden och redovisas som del av uppsatsens huvudresultat.

Two of the most common elevator algorithms, FS4 and FSO, are discussed in this thesis. Their pros and cons regarding passenger waiting time and energy consumption are compared to find which of the algorithms perform best and what factors affect this. These topics are of interest for owners of modern building.By developing a simulation program the behavior of elevators controlled by these algorithms were simulated. Passenger pattern in the simulation was meant to emulate the pattern that occurs in office buildings at lunch hour.The conclusion is that due to differences in sector usage and specific rules for each algorithm they have different strengths concerning waiting time and energy consumption, but overall the FS4 is the stronger choice.

Elevator systems have been quite similar for more than a hundred years and it has only quite recently become more feasible to have elevators being able to switch shafts allowing the construction of a system with more than two elevator cars in a single shaft. Such a system is to be constructed and tested during 2016 and functions using magnetic levitation technology. This new system calls for new algorithms to schedule the assignment of the passengers’ calls. Different strategies based on the collective control algorithm were developed to schedule the maglev system. The strategies were tested in a simulation of a twenty-five floor building and compared to a traditional system of one elevator car per shaft using the collective control scheduling strategy. The results show that in two out of the three scenarios simulated the maglev system performs better than the traditional system when average waiting time and average traveling time are compared. The traditional system beats the maglev system by a lot under the interfloor traffic scenario and adding more elevator cars improved the maglev systems performance but not enough to be as good as the tradition system. The conclusions drawn are that it is hard to schedule the maglev system to spread the cars out. It is also clear that the maglev system requires more elevator cars or improved scheduling to perform as well as the traditional system during the interfloor traffic scenario but is performing equally well or better during the up and down-peak scenarios. Further simulations are required to confirm these conclusions as the schedulers used are quite simple.

In 1950 Alan Turing introduced the famous “Turing test” which tests if a machine can be as intelligent as a human by testing if it can communicate with a person in a “human” way. Inspired by this test, numerous so called chatbots, in the form of computer programs, that manage a written dialogue have been created. A so called commonsensedatabase consists of data that most humans would know andconsider as common knowledge, something that computers generally do not know very muchabout. This report describes the process of an attempt to implement a simple chatbot using the common-sense database ConceptNet. The behaviour, or the human-likeness, of this chatbot was then compared to that of the classic chatbot ELIZA and the 2008 Loebner prize winning chatbot Elbot, through a series of user tests. The results indicate that using a common-sense database for a chatbot shows some promisefor further investigation.