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Supplemental material, sj-pdf-1-ppo-10.1177_07439156221103852 for Disinformation and Echo Chambers: How Disinformation Circulates on Social Media Through Identity-Driven Controversies by Carlos Diaz Ruiz and Tomas Nilsson in Journal of Public Policy & Marketing

Denna studie grundades dels i observationer i klasser i Naturvetenskapsprogrammet (NA) och teknikprogrammet (TE) där oväntade och oförklarliga skillnader mellan grupperna av studenter märktes, och dels i skillnader i statistiken som täcker dessa två program. Könsfördelningen är den mest uttalade skillnaden, där det är ungefär jämn fördelning på NA men med en betydande manlig överrepresentation på TE. Men det finns också skillnader i kulturell och utbildningsmässig bakgrund mellan de två grupperna av elever. Det är uppenbart att dessa skillnader inte uppstår under gymnasieskolan utan då eleverna väljer sitt program. Syftet med denna studie är därför att undersöka orsakerna till varför elever väljer som de gör, mellan dessa två program. De uppställda forskningsfrågorna är "På vad baserar sig elevernas val av natur/teknik?", "Vilken inställning har elever på de båda programmen till dessa när de väljer?" och "Finns det skillnader i hur elever på de två programmen fattar och motiverar sitt val?". Dessa frågor undersöks genom en intervjustudie där några studenter som just börjat på gymnasieskolan har fått berätta om sin erfarenhet från att välja program. Intervjuerna genomfördes under de första två veckorna på gymnasiet och inkluderade fem elever från NA och sex elever från TE. Eleverna intervjuades individuellt, vardera i ungefär en halvtimme, i ett semistrukturerat upplägg. Intervjuerna delades upp i två delar, där den första fokuserade på deras val och det valda programmet, och den andra tog upp det program som inte valdes. Intervjuerna analyserades utifrån en bred teoribas, inom områdena valprocess och motivering, begränsande zoner, och valteori. Resultaten av intervjuerna visar att eleverna i första hand väljer program baserat på vilka ämnen de är mest intresserade av, där eleverna på NA föredrar biologi och eleverna på TE föredrar teknik. Studien visar emellertid också att det finns skillnader mellan personligheten hos de elever som väljer de två programmen. Studien pekar på att elever som väljer NA generellt sett är bestämda i sitt val, de överväger endast i låg grad andra alternativ och bedömdes vara socialt starkare. Eleverna som väljer TE är, generellt, mer analyserande i sitt val och har tänkt igenom sitt val grundligt men bedömdes vara mindre socialt starka. This study was motivated by both observations in upper secondary school classes in the Swedish programs natural science programme (NA) and technology programme (TE), where unexpected and unexplained differences between the groups of students were seen, and by differences found in statistics covering these two programs. The gender distribution is the most pronounced difference, where this is about equal in NA but with a significant male overrepresentation in TE, but there are differences also in cultural and educational backgrounds among the two groups of students. It is obvious that these differences do not occur during education in upper secondary school but is established at the point when the students choose their program. The purpose of this study is therefore to investigate the causes and rationale for why students choose as they do, among these two programs. The scientific questions formed are 'On what are the students choice of NA/TE based?', 'What attitude do students have toward the programs when they choose?' and 'Are there any differences in how students at the two programs make and motivate their decisions?'. These questions are investigated through an interview study where some students who had just started at their upper secondary studies were asked to recount their experience from choosing program. The interviews were conducted during the first two weeks after the start of the semester and included five students from NA and six students from TE. The students were interviewed individually, each for about half an hour, according to a semi-structured scheme. The interviews were split into two parts, where the first focused on their choice and their selected program and the second brought up the program which was not selected. The interviews were analyzed according to several scientific theories, in the areas of processes and motifs, comfort zones and choice theory. The results of the interviews indicate that the students primarily choose programs based on the subjects they are most interested in, where the students at NA prefer biology and the students at TE prefer technology. However, the study also shows that there are differences between the personalities of the students who choose the two programs. The study shows that, in general, NA students are determined in their choice, they only make a limited consideration of other options and are considered to be socially stronger. The students at TE are more analytical in their selection and have thought their choices through thoroughly but were considered to be less socially competent.

Examensarbetet är en undersökning på hur det går att integrera Linux i en Microsoft AD-miljö. Detta genom att gå igenom de nödvändiga delarna för en lyckad autentisering. Arbetet tittar även på vissa skillnader mellan en Microsoft AD-miljö och en Samba AD-miljö vilket kan göra integreringen genomförbar eller inte. Undersökningen har gjorts med att ha Linux som klient mot en Microsoft AD-miljö men även att ha en Windows klient mot en Linux server installerad med Samba och dess AD-struktur. Tjänsterna som har inkluderats är de grundläggande tjänsterna så som inloggning och behörigheter gällande fildelning.

The transmissions of present heavy wheel loaders are in general based on torque converters. The characteristics of this component suits these machines, especially in that it enables thrust from zero vehicle speed without risk of stalling the engine, without active control. Unfortunately, the component also causes losses which might become large compared to the transmitted power. One approach for mitigating these losses is to switch to a continuously variable transmission. Changing to such a system greatly increases the possibility, and the need, for actively selecting the engine speed, and here a conflict emerges. A low engine speed is desired for high efficiency but a high speed is required for high power. Heavy wheel loaders often operate according to a common repeating pattern known as the short loading cycle. This cycle is extremely transient, which makes the choice of engine operating point both important and difficult. At the same time, the repeating pattern in the operation enables a rough prediction of the future operation. One way to use the uncertain prediction is to use optimization techniques for selecting the best control actions. This requires a method for detecting the operational pattern and producing a prediction from this, to formulate a manageable optimization problem, and for solving this, and finally to actually control the machine according to the optimization results. This problem is treated in the four papers that are included in this dissertation. The first paper describes a method for automatically detecting when the machine is operating according to any of several predefined patterns. The detector uses events and automata descriptions of the cycles, which makes the method simple yet powerful. In the evaluations over 90% of the actual cycles are detected and correctly identified. The detector also enables a quick analysis of large datasets. In several of the following papers this is used to condense measured data sequences into statistical cycles for the control optimization. In the second paper dynamic programming and Pontryagin’s maximum principle is applied to a simplified system consisting of a diesel engine and a generator. Methods are developed based on the maximum principle analysis, for finding the fuel optimal trajectories at output power steps, and the simplicity of the system enables a deeper analysis of these solutions. The methods are used to examine and visualize the mechanisms behind the solutions at power transients, and the models form the basis for the models in the following papers. The third paper describes two different concepts for implementing dynamic programming based optimal control of a hydrostatic transmission. In this system one load component forms a stochastic state constraint, and the concepts present two different strategies for handling this constraint. The controller concepts are evaluated through simulations, in terms of implementability, robustness against uncertainties in the prediction and fuel savings. The fourth paper describes the implementation and testing of a predictive controller, based on stochastic dynamic programming, for the engine and generator in a diesel electric powertrain. The controller is evaluated through both simulations and field tests, with several drivers, at a realistic work site, thus including all relevant disturbances and uncertainties. The evaluations indicate a ∼ 5% fuel benefit of utilizing a cycle prediction in the controller.

Recent development has renewed the interest in drivetrain concepts which gives a higher degree offreedom by disconnecting the engine and vehicle speeds. This freedom raises the demand for activecontrol, which especially during transients is not trivial, but of which the quality is crucial for the successof the drivetrain concept. In this work the fuel optimal engine operating point trajectories for a naturallyaspirated and a turbocharged diesel engine, connected to a load which does not restrict the engine speed,is derived, analysed and utilized for finding a suboptimal operating point trajectory. The analysis andoptimization is made with dynamic programming, Pontryagin’s maximum principle and a suboptimalstrategy based on the static optimal operating points. Methods are derived for using Pontryagin’smaximum principle for finding the optimal operating point trajectories, for simple load cases. The timeneeded for computation is reduced a factor 1000−100, depending on engine layout, compared to dynamicprogramming. These methods are only applicable to very simple load cases though. Finally, a suboptimalcalculation method which reduce the time needed for computation a factor > 1000 compared to dynamicprogramming, while showing a < 5% increase in fuel consumption compared to the optimal, is presented.

I denna studie används en kvantitativ metod i form av enkätstudie som är till för att ta reda på karaktärsämneslärares och kärnämneslärares undervisningsmetoder. Studien har genomförts på gymnasieskolan där författarna arbetar. För att få ut mer av enkätmetoden så ges de responderade möjlighet till att kommentera kring sina tankar på varje fråga. Syftet med studien var att ta reda på eventuella skillnader och likheter mellan karaktärsämneslärarna och kärnämneslärarna på skolan. I litteraturgenomgången redovisas centrala begrepp, tidigare forskning, förhållanden som styr inlärningen och olika undervisningsmetoder. Resultatet visar att de största skillnaderna är tid som avsätts till grupparbeten, antal studiebesök som görs, hur ofta gästföreläsare används, hur många muntliga redovisningar som görs, hur ofta eleverna får uppgifter som ger mening för andra att lösa och sist hur läraren betygsbedömer kursen. Några likheter som kom fram är att grupper blandas, kollegors material används mycket lite, infärgning av kurser samt infärgning av ämnen gör de flesta och de flesta lärare förklarar nya begrepp och metoder muntligt för eleverna. Det kom även fram punkter som verkar vara helt oberoende av lärartyp. Slutsatsen som vi kom fram till var att karaktärsämneslärarna och kärnämneslärarna har vissa skillnader mellan varandra men som de kan använda till att lära av varandra i den egna undervisningen.

Throughout the vehicular industry there is a drive for increased fuel efficiency. This is the case also for heavy equipment like wheel loaders. The operation of such machines is characterized by its highly transient nature, the episodes of high tractive effort at low speed and that power is used by both the transmission and the working hydraulics. The present transmission is well suited for this operation, though the efficiency is low in some modes of operation. Both operational advantages and efficiency drawbacks are highly related to the use of a torque converter. Continuously variable transmissions (CVTs) may hold a potential for achieving similar operability with reduced fuel consumption, though such devices increase the demand for, and importance of, active control. Common wheel loader operation is readily described in a framework of loading cycles. The general loading cycle is described, and a transmission oriented cycle description is introduced, in deterministic and stochastic forms, and a description is made on how such cycles are created from measurements. A loading cycle identifier is used for detecting cycles in a set of measured data, and a stochastic cycle is formed from statistics on the detected cycles. CVTs increase the possibility for active control, since a degree of freedom is introduced in the engine operating point. Optimal operating point trajectories are derived, using dynamic programming (DP), for naturally aspirated (NA) and turbocharged (TC) engines. The NA-engine solution is analyzed with Pontryagin’s maximum principle (PMP). This analysis is used for deriving PMP based methods for finding the optimal solutions for both engines. Experience show that these methods are 100 times faster than DP, but since the restrictions on the applicable load cases are severe, the main contribution from these is in the pedagogic visualization of optimization. Methods for deriving suboptimal operating point trajectories for both the NA and the TC engines are also developed, based on the optimization results. The methods are a factor >1000 faster than DP while producing feasible trajectories with less than 5% increase in fuel consumption compared to the optimal. Multi-mode CVTs provide the possibility of even higher efficiency than single mode devices. At the same time, the added complexity makes control development increasingly time consuming and costly, while the quality of the control is decisive for the success of the system. It is therefore important to be able to evaluate the potential of transmission concepts before control development commence. Stochastic dynamic programming is used and evaluated as a tool for control independent comparing of the present transmission and a hydrostatic multi-mode CVT concept. The introduction of a stochastic load complicates the optimization, especially in the feasible choice of states for the optimization. The results show that the multi-mode CVT has at least 15% lower minimum fuel consumption than the present transmission, and that this difference is not sensitive to prediction uncertainties.

Optimizing the configuration of a wheel loader to customer needs can lead to a significant increase in efficiency with respect to fuel economy, cost, component dimensioning etc. Experience show that even modest customer adaptation can save around 20% of fuel cost. A key motivator for this work is that wheel loader manufacturers in general does not have full information about customer usage of the machine and the main objective here is to develop an algorithm that automatically, using only production sensors, extracts information about the usage of a machine at a specific customer site. Two main challenges are that sensors are not located with respect to this task and the significant usage disturbances that typically occur during operation. The proposed solution is a robust method, based on a mix of techniques using basic signal processing, state automaton techniques, and parameter estimation algorithms. A key property of the method is the method of combining, individually very simple, basic techniques in a scheme where robustness are introduced. The approach is evaluated on measured data of a wheel loader loading gravel and shot rock.