The thesis deals with the issue of stability of voltage reference based on LTZ1000(A) integrated circuit. At the beginning are specified main parameters of voltage references in terms of stability. The work presents distribution references by architecture and by method of connection to the circuit. Work compares some references of Analog Devices and Linear Technology companies. In work is described voltage reference LTZ1000(A) and its circuits from datasheet. Listed are the main factor that influence the stability of reference, such as temperature, PCB design, Zener diode bias current, airflow and choice of circuit components. Given the description of a design module with the 7 V, 5 V and 10 V output. Made was three samples of PCB. Listed are results from long-term drift and temperature drift measures.

Post earnings announcement drift (PEAD) är den första erkända avvikelsen mot den effektiva marknadshypotesen och innebär att aktier tenderar att utvecklas i samma riktning som en resultatöverraskning. Denna studie undersöker förekomsten av PEAD för små bolag på First North och Stockholmsbörsen under perioden 2016–2022. Studien har genomförts som två eventstudier där daglig avkastning för små bolag på First North och Stockholmsbörsen har undersökts efter publicering av kvartalsrapport. Vår studie finner att First North uppvisar omvänd drift för upp till 60 handelsdagar efter kvartalsrapporter, vilket innebär att aktiekurser tenderar att utvecklas i motsatt riktning som kursreaktionen vid resultatöverraskningen. Vi fann ingen signifikant PEAD på Stockholmsbörsen, varken PEAD eller omvänd drift. Resultaten tyder på att First North överreagerar i samband med resultatöverraskningar, vilket sedan följs av en priskorrigering i efterföljande period. Detta indikerar att små bolag på First North har mindre effektiv prissättning än bolag med motsvarande storlek på Stockholmsbörsen.

ITC/USA 2007 Conference Proceedings / The Forty-Third Annual International Telemetering Conference and Technical Exhibition / October 22-25, 2007 / Riviera Hotel & Convention Center, Las Vegas, Nevada / As a vehicle reenters or flies at hypersonic speed through the atmosphere, the surrounding air is shock heated and becomes weakly ionized. The plasma layer thus formed causes a communication problem known as ‘radio blackout’. At sufficiently dense plasma conditions, the plasma layer either reflects or attenuates radio wave communications to and from the vehicle. In this paper, we propose an electromagnetic field configuration as a method to allow communication through the plasma layer. Theoretical models show that this may address the blackout problem under a range of conditions. Preliminary experimental results are also presented.

Denna rapport är skriven på och om Ringhals. Den beskriver i stora drag hur Ringhals jobbar för att hålla säkerheten på en hög nivå och hur de jobbar med miljön i fokus, som med t ex avfalls-och utsläppshanteringen. I rapporten kan man även läsa om underhållets och driftens organisation. På teknikavdelningen Nuclear teknik instrumentation analys (NTIA) pågår ett projekt där alla skrivare som sitter i kontrollrummen (KR) ska inventeras. Dessa skrivare ritar trender, från normalt ett flertal olika mätvärden, på papper. Inventeringen görs för att sammanställa information som status, fabrikat, placering och vilken information respektive skrivare presenterar. Det ska också undersökas om informationen som skrivarna presenterar finns tillgänglig i andra system. För att förstå var informationen eventuellt skulle kunna hämtas någonstans så beskrivs i rapporten system som blockdator (BUR), vibrationsdator, reaktorövervakningssystem (RÖS), turbinsystemet 800xA och processinformationssystem (PIS). Huvudsyftet är att detta arbete ska vara en del av det underlag som ingår i ”R34 Målkontrollrum”. ”R34 Målkontrollrum” ska i sin tur vara vägledande gällande hur anläggningarna ska kunna vidmakthållas till en effektiv kostnad. Resultatet av denna rapport visade att det inte var speciellt många mätvärden som kunde fås från de andra systemen utöver pappersskrivarna. Det ligger nu i övriga projektmedlemmars händer att med hjälp av denna inventering besluta vilka skrivare som kan plockas bort och vilka som bör bytas ut till s.k. Loggers.

Ventilationssystem tar ofta mycket plats och kan beroende på utformning påverka bygghöjden. Studentbostäder kräver låga hyror och därmed låga produktionskostnader. Examensarbetet visar hur ventilationssystemet kan byggas in i ett innovativt installationsbjälklag och på så sätt spara bygghöjd. Lägre bygghöjd leder till lägre kostnader.

We theoretically investigate the fluid mechanics of self-propelled (or swimming) bodies. An important factor concerning the hydrodynamics of locomotion concerns the relative strength of inertial to viscous forces experienced by the swimmer, the ratio of which is quantified by the Reynolds number, Re. Particular attention is given to the regime where Re is intermediate, where viscous and inertial forces are both relevant to fluid motion. We study two broad classes of swimmers: ‘pushers’ and ‘pullers’. Pushers produce thrust from the rear of their body, while pullers generate thrust from the front. We first investigate the near-field flow due to pushers and pullers by numerically solving the Navier-Stokes equations for Re of 0.01–1000. We show that, although the locomotion of pushers and pullers is similar at small Re, drastic differences due to fluid inertia arise as Re is increased. Most remarkably, flow instabilities develop at much smaller Re for a puller than a pusher. Further, we investigate the large scale fluid transport induced by a swimmer as a function of Re in the context of the induced ‘drift volume’. The drift volume quantifies the volume of fluid swept out by a ‘dyed’ fluid plane that is initially perpendicular to the body’s path. However, we first address the previously unsolved problem of the drift volume due to a body that is towed by an external force at finite Re. While the drift volume is comparable to the body volume in inviscid flow (Re ! 1), it is much larger when Re is finite due to viscous effects. The drift volume due to a swimmer is smaller than that due to a towed body because swimmers generate a weaker far-field flow. However, it is still potentially large compared to the volume of the swimmer’s body in the viscously dominated small-Re regime. However, the drift volume of a swimmer quickly diminishes as Re is increased.

The term hydropeaking refers to anthropogenically induced, short-duration, high-magnitude discharge pulses that are generated in lotic systems for electricity production. The practice of hydropeaking produces the largest source of renewable energy worldwide, and its use is projected to increase through the year 2040. The primary objective of this work was to evaluate the effects of hydropeaking on benthic macroinvertebrate assemblages, which are important components of lotic ecosystems. Results of this work show that, across a wide range of impacted systems worldwide, the consistently observed patterns of elevated benthic macroinvertebrate drift in response to hydropeaking pulses are primarily related to the rate at which discharge is increased (i.e., ramping rate) and secondarily to the time between pulses. In addition, it was shown that taxa inhabiting depositional habitat patches (i.e. fine substrates and slow water velocities) were most susceptible to peaking-induced drift, and that these taxa were also those most prevalent in hydropeaking-impacted systems. Collectively, these results suggest that increased pulse ramping rate and the resulting elevated macroinvertebrate drift may be positive selective forces, which benefit populations adapted for life in hydropeaking-impacted lotic ecosystems. These results provide a greater understanding of the factors that are most important for governing the effects of hydropeaking on benthic assemblages.

Purpose: The introduction of median divided carriageways, MDC, has brought difficulties to the performing of maintenance tasks and operational improvements without disrupting traffic or compromising work safety. Meanwhile, cyclists have suffered deteriorating conditions along these roads. The aim of this study was to investigate whether the operational and maintenance tasks on this road type can be facilitated by the use of a parallel road, which can also be used for bicycle traffic. Method: The work is mostly based on qualitative semi-structured interviews with both operating entrepreneurs and representatives from the client side. Alongside this, some literaturestudy has been made. Findings: Work safety is a concern when working at MDC. For major planned actions, redirecting traffic is always the first option, but it can be difficult to find suitable diversion routes. It is more expensive to operate MDC than conventional carriageways, but there are no key formulas that tell you how much more expensive. Along some difficult stretches, especially 1 + 1 sections, some measures may be withheld or delayed. The benefits of a parallel road are many, especially for rerouting traffic. Some operations could also be conducted from a parallel road if it is close enough to the main road. If the parallel road is to be used for operation and maintenance as well as bicycle traffic, the road cannot be converted into cycling way as other vehicles can be expected to appear. Implications: The benefit of a parallel road is primarily the ability to reroute traffic. Diversion will probably become even more relevant in the future, with more narrow median divided carriageways sections combined with increased focus on work safety. The tasks that can be conducted from the parallel road makes such demands on the placement of the parallel road, that the benefits in relation to this are probably limited. The combined use for traffic redirection and cycling can be a good alternative, but this must be looked at from a project-specific perspective as the conditions are so different. Limitations: Conditions differ hugely in all projects. This report is intended for general application and can be viewed as a tool where one or more solutions can be applicable to the project. The financial aspect is not considered in this project. Maximum improvement for cyclists has not been studied in this project, operational and maintenance aspects have been prioritised. / Syfte: Införandet av mötesfria landsvägar, MLV, har inneburit svårigheter att utföra drift- och underhållsarbeten utan att störa trafiken eller äventyra arbetsmiljön. Samtidigt har cyklisterna ofta fått försämrade förutsättningar längs dessa vägar. Målet med detta examensarbete var att utreda hur drift och underhåll av MLV kan underlättas av en parallellväg som även kan användas för cykeltrafiken. Metod: Arbetet bygger till stor del på kvalitativa undersökningar i form av semistrukturerade intervjuer med både driftsentreprenörer och representanter från beställarsidan. Vid sidan om detta har litteraturstudier gjorts. Resultat: Arbetsmiljön är ett bekymmer vid arbete på MLV. Vid större planerade åtgärder är alltid omledning av trafiken första alternativet, men det kan vara svårt att finna lämpliga omledningsvägar. Det är dyrare att sköta MLV än vanlig motsvarande väg, men man har inga nyckeltal som talar om hur mycket dyrare. Längs vissa komplicerade sträckor, i synnerhet med 1+1-sektion, kan vissa drift- och underhållsåtgärder utebli eller försenas. Nyttan av en parallellväg är stor, framför allt för omledning av trafiken. Vissa arbetsmoment skulle också kunna utföras från parallellvägen om den ligger tillräckligt nära huvudvägen. För att samnyttja parallellvägen för drift, underhåll och cykeltrafik kan vägen inte antas som cykelväg i vägplan då även andra trafikslag kan förväntas förekomma. Konsekvenser: Nyttan av en parallellväg är framförallt möjligheten att leda om trafiken. Omledning kommer antagligen bli än mer aktuellt framöver, med fler smala MLV-sektioner i kombination med ökat fokus på arbetsmiljön. De arbeten som kan göras från parallellvägen ställer sådana krav på placeringen av vägen att nyttan i förhållande till detta antagligen är begränsad. Att samnyttja omledningstrafiken med cykeltrafik kan vara ett gott alternativ, men detta måste ses ur ett projektspecifikt perspektiv då förutsättningarna är så olika. Begränsningar: Förutsättningarna är så olika i alla projekt. Rapporten är skriven för att gälla generellt och kan ses som en verktygslåda där en eller flera lösningar är applicerbara i projektet. Den ekonomiska aspekten är inte beaktad i detta projekt. Vad som innebär hög måluppfyllelse för cyklister har inte studerats i detta projekt, drift- och underhållsaspekten har prioriterats.

In this thesis, learning refers to the intelligent computational extraction of knowledge from data. Supervised learning tasks require data to be annotated with labels, whereas for unsupervised learning, data is not labelled. Semi-supervised learning deals with data sets that are partially labelled. A major issue with supervised and semi-supervised learning of data streams is late-arriving or missing class labels. Assuming that correctly labelled data will always be available and timely is often unfeasible, and, as such, supervised methods are not directly applicable in the real world. Therefore, real-world problems usually require the use of semi-supervised or unsupervised learning techniques. For instance, when considering a spam detection task, it is not reasonable to assume that all spam will be identified (correctly labelled) prior to learning. Additionally, in semi-supervised learning, "the instances having the highest [predictive] confidence are not necessarily the most useful ones" [41]. We investigate how self-training performs without its selective heuristic in a streaming setting. This leads us to our contributions. We extend an existing concept drift detector to operate without any labelled data, by using a sliding window of our ensemble's prediction confidence, instead of a boolean indicating whether the ensemble's predictions are correct. We also extend selective self-training, a semi-supervised learning method, by using all predictions, and not only those with high predictive confidence. Finally, we introduce a novel windowing type for ensembles, as sliding windows are very time consuming and regular tumbling windows are not a suitable replacement. Our windowing technique can be considered a hybrid of the two: we train each sub-classifier in the ensemble with tumbling windows, but delay training in such a way that only one sub-classifier can update its model per iteration. We found, through statistical significance tests, that our framework is (roughly 160 times) faster than current state of the art techniques, and achieves comparable predictive accuracy. That being said, more research is needed to further reduce the quantity of labelled data used for training, while also increasing its predictive accuracy.

Enterprise Resource Planning (ERP) systems are information systems that integrate organizational activities across geographical and functional divisions. Being enterprise-wide systems, they are used within an organization in order to standardise its data and streamline its business processes. However, the envisaged benefits of installing an ERP system, such as better control over the company’s operations and seamless integration and data exchange, often fail to materialize. Although the literature has looked into the factors affecting a successful ERP implementation and adoption, it has largely overlooked the actual use of the system. However, as ERP systems have become widespread in many organizations, it is important to examine the use of such systems and their organizational consequences in-situ. This research is particularly concerned with the impact of the use of ERP systems on organizational control and drift. The main argument is that there are contextual factors, in the form of existing organizational control and drift, which influence the use of the ERP system by its users. The actual use of the ERP system can then also lead to organizational control or drift itself. This depends on the way the system is used by its users, as well as the affordances of the system. The former is characterized as human agency in this thesis, while the latter is characterized as machine agency. An interpretive case study approach is adopted to examine those issues. A main case study is examined in depth, aided by four auxiliary case studies. The main contribution of this research is the provision of rich insights regarding the use of ERP systems and their organizational consequences.