Multiple Loop Self-Triggered Model Predictive Control for Network Scheduling and Control

We present an algorithm for controlling and scheduling multiple linear time-invariant processes on a shared bandwidth limited communication network using adaptive sampling intervals. The controller is centralized and computes at every sampling instant not only the new control command for a process, but also decides the time interval to wait until taking the next sample. The approach relies on model predictive control ideas, where the cost function penalizes the state and control effort as well as the time interval until the next sample is taken. The latter is introduced in order to generate an adaptive sampling scheme for the overall system such that the sampling time increases as the norm of the system state goes to zero. The paper presents a method for synthesizing such a predictive controller and gives explicit sufficient conditions for when it is stabilizing. Further explicit conditions are given which guarantee conflict free transmissions on the network. It is shown that the optimization problem may be solved off-line and that the controller can be implemented as a lookup table of state feedback gains. Simulation studies which compare the proposed algorithm to periodic sampling illustrate potential performance gains.Comment: Accepted for publication in IEEE Transactions on Control Systems Technolog

A dynamic capabilities approach

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Cycles of Innovation and Alignment in Digital Transformation: Investigating the Dynamics of Resource Recombination in a Construction Firm

The generative nature of digital technology implies that during digital transformation (DT), organizations traverse multiple cycles of innovation and resource alignment. Still, extant research mainly chronicles DT as linear and contained phenomenon occurring in response to a dramatic environmental change event. How new resources align with previous ones into novel combinations, the work that supports continuous organizational capability building, and the temporal relationships between cycles of change in DT has received scant attention. Drawing on dynamic capability theory, we analyze innovation and resource alignment cycles driving DT at Lundqvist Trävaru AB, a small Swedish construction firm. Our study has at least two contributions. First, the analysis reveals three types of dynamic capabilities that shape resource generation and alignment in DT. Second, we provide a process model outlining the innovation and alignment cycles that fuel DT as they scale in the focal firm

Lessons from the Regulation of E-scooters through the MDS Standard: Policy Lessons for Connected Vehicles

Connected vehicles generate new data streams that present promising opportunities for policymakers to monitor and learn from events and behavior. To explore what we can learn from how public entities leverage ubiquitous data streams for policy development and enforcement, we draw on a case study of the standard Mobility Data Specification (MDS) and its use by cities to regulate E-scooter operators. Our findings suggest that (1) the richness of real-time data changes the speed of policy revision, (2) data access enables moving some micro-decisions to the edge, and (3) policy will be formulated as fixed or flexible with different amendment rules

Identification of Outflows and Candidate Dual Active Galactic Nuclei in SDSS Quasars at z=0.8-1.6

We present a sample of 131 quasars from the Sloan Digital Sky Survey at redshifts 0.8<z<1.6 with double peaks in either of the high-ionization narrow emission lines [NeV]3426 or [NeIII]3869. These sources were selected with the intention of identifying high-redshift analogs of the z<0.8 active galactic nuclei (AGN) with double-peaked [OIII]5007 lines, which might represent AGN outflows or dual AGN. Lines of high-ionization potential are believed to originate in the inner, highly photoionized portion of the narrow line region (NLR), and we exploit this assumption to investigate the possible kinematic origins of the double-peaked lines. For comparison, we measure the [NeV]3426 and [NeIII]3869 double peaks in low-redshift (z<0.8) [OIII]-selected sources. We find that [NeV]3426 and [NeIII]3869 show a correlation between line-splitting and line-width similar to that of [OIII]5007 in other studies; and the velocity-splittings are correlated with the quasar Eddington ratio. These results suggest an outflow origin for at least a subset of the double-peaks, allowing us to study the high-ionization gas kinematics around quasars. However, we find that a non-neligible fraction of our sample show no evidence for an ionization stratification. For these sources, the outflow scenario is less compelling, leaving the dual AGN scenario as a viable possibility. Finally, we find that our sample shows an anti-correlation between the velocity-offset ratio and luminosity ratio of the components, which is a potential dynamical argument for the presence of dual AGN. Therefore, this study serves as a first attempt at extending the selection of candidate dual AGN to higher redshifts.Comment: 19 pages, 12 figures, accepted for publication in The Astrophysical Journa

The robot and other grass cutting machinery development and future potential in the home garden

Detta arbete har undersökt om gräsmatteskötsel kan förenklas genom modern teknik i form av robotgräsklippare. Idén till uppsatsen bottnar i hur trädgårdsägare skall kunna förenkla arbetet i trädgården. Istället för att lägga ner massor av tid och arbete på gräsklippning ska man kunna ha sin trädgård mera som rekreation. Uppsatsen trycker även på hur gräskvaliteten skall bli den bästa med minsta möjliga ansträngning. Utöver detta nämns även gräsmattans historia, gräsarter och hur den framtida utvecklingen av robotgräsklippare skulle kunna se ut. Idag används olika gräsklipparprodukter beroende på hur stor yta som behöver klippas. Till de större ytorna (2000 m2) används idag ofta åkgräsklippare. Marknaden har också börjat erbjuda robotgräsklippare som sägs sköta gräsmattan utan tillsyn. Hur bra är dessa? Kan de konkurrera med de traditionella gräsklipparna? Det är en del av vad detta arbete kommer att ta upp. Målet med detta arbete är att utvidga kunskapen om hur gräset kan skötas på ett så extensivt sätt som möjligt med bra kvalitet, miljövänlighet och ekonomisk hållbarhet. De besvaras på tre olika sätt: genom litteraturstudie, en ekonomidel och en visuell bedömning innehållande en intervju. En återblick har även gjorts vid tidigare tester från oberoende tidskriftsföretag Råd och rön, Smartson och Aftonbladet (Härligt hemma). Då ett flertal robotgräsklippare jämförts med traditionella gräsklippare går det genom denna studie att säga att flera villaägare anser att robotgräsklippare är något för framtiden. Robotgräsklipparen sköter arbetet med att klippa gräset för de som inte har ork och för de om inte har tid. Samtidigt bidrar de till att hålla efter gräsmattan. Troligtvis bättre än traditionella klippare, genom att de skapar en konstant mullhalt i jorden vilken förbättrar mikrolivet som i sin tur stärker gräset. Då robotgräsklipparens marknad bara under de senaste åren har exploderat med många nya modeller och konsumenternas behov och efterfrågan är väldigt stor visar detta på att robotgräsklippare troligtvis är det som gäller i framtiden för hemträdgården.This work tries to explain how lawn care can be simplified by using modern technology in the form of robotic mowers. The idea for the thesis stems from how the garden owners will be able to simplify the work in the garden. Instead of spending lots of time and effort in mowing, should it be able to have the garden more like recreation. The thesis also shows how the grass quality will be the best with the least possible effort. Today the lawn mowing products which use is depending on the surface area that needs mowed. To the larger surfaces (2000 m2) are rider often used. The market has also begun to offer robotic lawnmower that is said to take care of the lawn unattended. How good are these? Can they compete with the traditional mowers? That is a part of what this work will take up. The goal of this work is to extend our knowledge of how the grass can be managed in the most extensive way possible with good quality, environmental and economic sustainability. They answered in three different ways: through literature study, an economy section and a visual assessment containing an interview. A review was also made at the previous tests from independent magazine business advice and knowledge, Råd och rön, Smartson and Aftonbladet (Härligt hemma). When a plurality of robotic mowers compared with a traditional mower goes through this study, shows that many homeowners find that robotic lawnmower is something for the future. The robotic lawn mower handles the work of cutting the grass for those who do not have the energy, and for those who do not have time. At the same time, they help to keep after the lawn. Probably better than traditional clippers, by creating a constant humus content in the soil, which improves the micro-life, which in turn strengthens the grass. When the robotic mower market only in recent years has exploded with many new models and consumer, needs and demand is very large. This shows that the robotic mower is probably that thing of the future in the home garden

Progression of RNA-sequencing to single-cell applications

New methods enable new discoveries. My time as a PhD student has run in parallel with the maturation of the RNA-seq method, and I have used it to discover basic properties of gene expression and transcriptomes. My part has been bioinformatics – the computer analysis of biological data. RNA-seq quantifies gene expression for all genes in one experiment, allowing discoveries without prior knowledge, as opposed to single-gene hypothesis testing. When I started my PhD, this was done by microarray followed by qRT-PCR validation, which can be arduous. In contrast to microarrays, RNA-seq quantifies expression with little ambiguity of which gene each expression value corresponds to, and in absolute terms. But at the time, data analysis of RNA-seq was full of unknowns and there were little software available. Nowadays, partly the result of my work, the data analysis is much less complicated, and RNA-seq can be performed on diminutive samples, down to single cells, which was not viable using microarrays. My first study (Paper I) used one of the very first RNA-seq datasets to study general features of transcriptomes, such as mean mRNA length (~1,500 nt) and the number of genes expressed per tissue (~13,000). I also found special features of some tissues: the liver transcriptome is dominated by a few highly expressed gene, brain expresses especially long mRNAs and testis expresses many more genes than other tissues. Following this tissue RNA-seq study, I evaluated a new library preparation method for single-cell RNA-seq (Paper III), developed before the prevalence of single-cell RNA-seq. I used technical replicates to show that the method was accurate and reliable for the more highly expressed genes at single-cell RNA levels, and with input RNA amounts corresponding to >50 cells it produced as good quality data as bulk RNA-seq. Then the method was applied on melanoma cells isolated from human blood, and I listed surface antigen genes that distinguished these circulating tumour cells from other cells in the blood. This single-cell RNA-seq method was then applied on pre-implantation embryo cells (Paper IV). Using first-generation crosses between two mouse strains, I could separate the expression from the maternal and the paternal copies of the genes. I found that 12-24% of the genes express only one of their two copies in any given cell, in a random manner that affects almost all the expressed genes. I also found that the two copies are expressed independently from each other. Finally, I studied Sox transcription factors during neural development (Paper II), combining RNA-seq and microarray data for different cell types with ChIP-seq data for transcription factor binding and histone modifications. I found that Sox proteins bind to the enhancers active in the stem cells where the Sox proteins are active, but also to enhancers specific to subsequent cells in ii development. I also found that different Sox factors bind to much the same enhancers, and that they can induce histone modifications. In conclusion, my work has advanced the RNA-seq method and increased the understanding of transcriptional regulation and output