In this dissertation I investigate and compare the impairments of long-lived operating assets under US Generally Accepted Accounting Principles (US GAAP) and International Financial Reporting Standards (IFRS) from different perspective, including the informativeness, determinants, and market valuation of asset impairments. A firm invests in long-lived operating assets with the expectation of generating future benefit. The decision or recognition of asset impairments implies such future benefit is expected to be lower than originally estimated. US GAAP and IFRS both require the recognition of impairment losses but their standards and accounting approaches are different in several ways. These distinctions raise the question whether the reported long-lived asset impairments under US GAAP and IFRS are comparable and motivate this dissertation. I investigate the predictive ability of reported asset write-offs for firms' future performance and find negative associations suggesting the informativeness of impairment losses. But such informativeness depends on the type of assets impaired, the accounting standards adopted, and the institutional characteristics. In general, aggregate impairments are persistently associated with future performance under IFRS but not US GAAP. The impairments of tangible assets have more predictive ability than those of intangibles. For IFRS adopters, enforcement takes a more important role in determining the informativeness of asset impairments than legal origins. I also examine the determinants and attributes of asset impairments under US GAAP and IFRS. I find both of them reflect certain economic factors and reporting incentives. Under US GAAP asset impairments strongly reflect GDP growth, unemployment rate, industry-trend and reporting incentives, including taking a big bath and income smoothing. Under IFRS the impairments reflect most economic factors but less reporting incentives. However, when enforcement is low in IFRS countries, firms tend to manage earnings through asset write-offs. I further address the market valuation of asset write-offs under US GAAP and IFRS. The reporting of asset impairments improves the explanatory power of accounting information for equity prices under IFRS but not US GAAP, especially when enforcement is high. The associations between asset write-offs and equity prices under IFRS in high enforcement countries are significantly different from those under US GAAP, implying investors weigh reported impairments under IFRS. I also use stock returns as an alternative metric of market valuation. Under US GAAP, asset write-offs are negatively associated with past, current, and future stock returns. Under IFRS in high enforcement countries the effects of impairment loss concentrate on past and current stock returns. The results of comparisons suggest asset write-offs under US GAAP and IFRS are not totally comparable from a market perspective. This dissertation contributes to literature on special items, impairment accounting, and reporting under IFRS. It is also related to the comparability of financial reporting under US GAAP and IFRS. While studies have compared overall properties of the two standards, examining the differences in a specific accounting area is also important as U.S. SEC express concern about the convergence of different accounting standards and whether U.S. should incorporate IFRS into its financial reporting systems. / Business Administration/Accounting

The layer-by-layer nature of additive manufacturing (AM) allows for access to the entire build volume of a component during manufacture including the internal structure. Voids are accessible during the build process and allow for components to be embedded and sealed with subsequently printed layers. This process, in conjunction with direct write (DW) of conductive materials, enables the direct manufacture of parts featuring embedded electronics, including interconnects and sensors. The scope of previous works in which DW and AM processes are combined has been limited to single material AM processes. The PolyJet process is assessed for hybridization with DW because of its multi-material capabilities. The PolyJet process is capable of simultaneously depositing different materials, including rigid and elastomeric photopolymers, which enables the design of flexible features such as membranes and joints. In this work, extrusion-based DW is integrated with PolyJet AM technology to explore opportunities for embedding conductive materials on rigid and elastomeric polymer substrates. Experiments are conducted to broaden the understanding of how silver-loaded conductive inks behave on PolyJet material surfaces. Traces of DuPont 5021 conductive ink as small as 750?m wide and 28?m tall are deposited on VeroWhite+ and TangoBlack+ PolyJet material using a Nordson EFD high-precision fluid dispenser. Heated drying at 55°C is found to accelerate material drying with no significant effect on the conductor's geometry or conductivity. Contact angles of the conductive ink on PolyJet substrates are measured and exhibit a hydrophilic interaction, indicating good adhesion. Encapsulation is found to negatively impact conductivity of directly written conductors when compared to traces deposited on the surface. Strain sensing components are designed to demonstrate potential and future applications. / Master of Science

NAND flash-based Solid State Devices (SSDs) provide high performance and energy efficiency and at the same time their capacity continues to grow at an unprecedented rate. As a result, SSDs are increasingly being used in high end computing systems such as supercomputing clusters. However, one of the biggest impediments to large scale deployments is the limited erase cycles in flash devices. The natural skewness in I/O workloads can results in Wear imbalance which has a significant impact on the reliability, performance as well as lifetime of the cluster. Current load balancers for storage systems are designed with a critical goal to optimize performance. Data migration techniques are used to handle wear balancing but they suffer from a huge metadata overhead and extra erasures. To overcome these problems, we propose an endurance-aware write off-loading technique (EWO) for balancing the wear across different flash-based servers with minimal extra cost. Extant wear leveling algorithms are designed for a single flash device. With the use of flash devices in enterprise server storage, the wear leveling algorithms need to take into account the variance of the wear at the cluster level. EWO exploits the out-of-place update feature of flash memory by off- loading the writes across flash servers instead of moving data across flash servers to mitigate extra-wear cost. To evenly distribute erasures to flash servers, EWO off-loads writes from the flash servers with high erase cycles to the ones with low erase cycles by first quantitatively calculating the amount of writes based on the frequency of garbage collection. To reduce metadata overhead caused by write off-loading, EWO employs a hot-slice off-loading policy to explore the trade-offs between extra-wear cost and metadata overhead. Evaluation on a 50 to 200 node SSD cluster shows that EWO outperforms data migration based wear balancing techniques, reducing up to 70% aggregate extra erase cycles while improving the write performance by up to 20% compared to data migration. / Master of Science

I dagens samhälle är det av stor vikt att kunna läsa och skriva då texter finns i olika former överallt, mycket på grund av den tekniska utvecklingen i samhället. Vägen till att "knäcka koden" ser olika ut för barn. I studien har vi valt att fokusera elever med läs- och skrivsvårigheter samt hur tekniken kan fungera som stöd i undervisningen. Syftet med studien är att undersöka hur lärare beskriver sin undervisning i förhållande till läs- och skrivsvårigheter. Vidare är syftet att undersöka hur elever med läs- och skrivsvårigheter upplever sin undervisning. Studien har sin utgångspunkt i den sociokulturella teorin. Empirin till studien är skapad genom semistrukturerade intervjuer med lärare och elever. Materialet har sedan analyserats och presenteras i resultatet. Resultatet av studien indikerar på att undervisning och stödstrukturer inom ASL stödjer elever med läs- och skrivsvårigheter i sin läs- och skrivinlärning genom att de får höra och se sambandet mellan ljud och bokstav. / In today's society it's important to be able to read and write because there are texts everywhere, and also as the technology has made a bigger impact in the society. For some children it can be difficult to learn how to write and read. Because of this we have chosen to focus on pupils with disabilities in the read- and writing process. We also want to see how the technology can support pupils in their learning. The aim of this study is therefore to investigate how teachers describe their teaching in relation to reading and writing disabilities. The study also aims to investigate how pupils with reading and writing disabilities describe their education. The sociocultural theory is the base of this study. The empirics to this study is created by interviews with pupils and teachers. The empirics has been analyzed and presented in the result. The result of this study shows that the method "write to read" supports pupils with writing and reading disabilities in their writing and reading education because the link between letter and sound clarifieds for the pupils.

There currently does not exist a way for creating digital twins’information and transferring it between networks , but container-basedvirtualization could be a possible solution. One of those techniques isDocker, which is an engine to isolate a software and can bring benefits toimprove the workflow of software development. Making changes withDocker is very fast as it uses the copy-on-write model, it can containerizeapplications in minutes. This study will design a scenario with twodevices sending a data packet between each other to simulate theproblem. The results from the study is further investigate and analyze toanswer the question of whether the container-based virtualization can bea possible solution for creating digital twins. The result from the scenariois Docker works equal or worse when used with a low-cost computinghardware compared to a computing hardware. It is speculated that theresources used in the images is a factor that can affect the performance,but the hardware is also another factor that can affect it. / Det finns för närvarande inget sätt att skapa digitala tvillingar ochöverföra den mellan nätverk, men containerbaserad virtualisering kanvara en möjlig lösning. En av containerbaserad virtualisering tekniker ärDocker, som är en motor för att isolera en programvara och kanframbringa fördelar för att förbättra arbetsflödet för programutveckling.Att göra ändringar med Docker är mycket snabbt tack vare användningav copy-on-write-modellen. Denna studie kommer att utforma ettscenario med två enheter som skickar ett datapaket mellan varandra fratt simulera överföringsprocessen. Mätresultat från studien bliranalyserad för att besvara frågan om containerbaserad virtualisering kanvara en möjlig lösning för att skapa och skicka digitala tvillingar.Resultatet från scenariot är att Docker fungerar lika eller sämre när detanvänds med en låg kostnad datorhårdvara jämfört med endatorhårdvara. Det spekuleras att resurserna som används i datapaketetär en faktor som kan påverka prestandan, men hårdvaran är också enannan faktor som påverkar det.

Syftet med studien är att undersöka hur lärare beskriver möjligheter och hinder med traditionell skrivinlärning respektive digital skrivinlärning genom metoden ASL. Målet är att bidra med kunskap om hur metoderna kan användas i undervisningen. Fyra forskningsfrågor ställdes utifrån syftet: Hur beskriver lärare att de arbetar med traditionell skrivinlärning? Hur beskriver lärare att de arbetar med ASL? Vilka fördelar finns det med metoderna anser lärare? Vilka nackdelar finns det med metoderna anser lärare? Studien har sin utgångspunkt i det sociokulturella perspektivet. En kvalitativ metod har använts för att genom semistrukturerade intervjuer samla in data. Respondetnerna bestod av fem lärare, yrkesverksamma i grundskolans lägre åldrar. Studiens empiri analyserades genom en tematisk analysmetod där materialet färgkodades med utgångspunkt i hur studiens forskningsfrågor besvarades. Resultatet visar hur fem lärare undervisar traditionell skrivinlärning och digital skrivinlärning samt vad det finns för möjligheter och hinder med de båda metoderna. / The purpose of the study is to investigate how teachers describe opportunities and barriers with traditional writing acquisition through WTR. The goal is to provide knowledge about how the methods can be used in teaching. Four research questions were asked based on the aim: How do teachers describe that they work with traditional writing acquisition? How do teachers describe that they work with WTR? What are the advantages of the methodes according to teachers? What are the disadvantages of the methodes according to teachers? The study is based on the socio-cultural perspective. A qualitative method has been used to collect data through semi-structured interviews. The respondents were of five teachers who work in primary schools. The collected material was analyzed with the help of a thematic analysis method in which the collected material was color-coded according to how it respondse to the questions of the study. The findings shows how teachers work with traditional writing and digital writing in school, as well as what there are for opportunities and barriers there are in connection with the two methodes.

Compared to traditional hard-disk drives (HDDs), non-volatile (NV) memory technologies offer significant performance advantages on one hand, but also incur significant cost and asymmetric write-performance on the other. A common strategy to manage such cost- and performance-differentials is to use hierarchies such that a small, but intensely accessed, working set is staged in the NV storage (selective caching). However, when this working set includes write-heavy data, the low write-lifetime of NV storage necessitates significant over-provisioning to maintain required lifespans (e.g., storage lifespan must match or exceed 3 year server lifespan). One may think that employing DRAM-based write-buffers can filter writes that trickle through to the NV storage and thus alleviate the write-pressure felt at the NV storage. Unfortunately, selective caches, when used with common recency-based or frequency-based replacement, have access patterns that require large write buffers (e.g., 100MB+ relative to a 12GB cache) to filter writes adequately. Further, these large DRAM write-buffers also require backup-power to ensure the durability of disk writes. More sophisticated replacement policies that combine recency and frequency can reduce the size of the DRAM buffer (while preserving write-filtering), but are so computationally-expensive that they can limit the I/O rate, especially for simple controllers (e.g., RAID controller). <br>My first contribution is the design and implementation of WriteGuard– a self-tuning sieving write-buffer algorithm that filters writes as well as the highly-effective (but computationally-expensive) algorithms while requiring lightweight computation comparable to a simple LRU-based write-buffer. While WriteGuard reduces the capacity needed for DRAM buffering (to approx. 64 MB), it does not eliminate the need for DRAM buffers (and corresponding power backup).<br>For my second thrust, I identify two specific application characteristics – (1) the vast majority of the write-buffer’s contents is composed of write-dominant blocks, and (2) the vast majority of blocks in the write-buffer are overwritten within a period of 28 hours. I show that these characteristics help enable a high-density, optimized STT-MRAM as a replacement for DRAM, which enables durable write-buffers (thus eliminating the cost of power backup for the write-buffer). My optimized STT-MRAM-based write buffer achieves higher density by (a) trading off superfluous durability by exploiting characteristic (2), and (b) deoptimizing the read-performance of STT-MRAM by leveraging characteristic (1). Together, the techniques increase the density of STT-MRAM by 20% with low or no impact on write-buffer performance.<br>

This report discusses the design of read/write assist circuits which are used in a SRAM cell’s design to overcome the cell’s variations. It also explains the variability problems in a SRAM bit-cell and many approaches to address them. The basic operations, SNM concept, and write margin of an SRAM are described theoretically as well as measured in simulation. The write assisted circuit, the Negative Bit-line Voltage Bias scheme, is discussed and implemented at transistor level using a six-transistor (6T) SRAM cell. With the write assisted circuit, the implemented memory array successfully performs a write operation at 0.6V and -25°C, the condition in which the same operation would fail without the write assisted circuit. During the simulation, this write assisted circuit helps to achieve the negative bias voltage of -70mV on the SRAM’s bit-lines. The cost overhead includes chip area, power consumption, and current leakage when this Negative Bit-line Voltage scheme is implemented. / text

A wide variety of tunable physio-chemical properties make ZnO nanowires a promising candidate for functional device applications. Although bottom-up grown nanowires are producible in volume, their high-throughput device integration requires control over dimensions and, more importantly, of precise placement. Thus development of top-down fabrication routes with accurate device positioning is imperative and hence pursued in this thesis. ZnO thin film transistors (TFT) were fabricated using solution based precursor zinc neodecanoate. A range of ZnO thin films were prepared by varying process parameters, such as precursor concentrations and annealing temperatures, and then analysed for their optical and electrical characteristics. ZnO TFTs prepared from a 15 % precursor concentration and annealing at 700 $^\circ$C exhibited best device performance with a saturation mobility of 0.1 cm$^2$/V.s and an on/off ratio of 10$^7$. Trap limited conduction (TLC) transport was found to be dominant in these devices. A direct-write electron beam lithography (EBL) process was developed using zinc naphthenate and zinc neodecanoate precursors for the top-down synthesis of ZnO nanowires. Nanoscale ZnO patterns with a resolution of 50 nm and lengths up to 25 $\mu$m were fabricated. A linear mobility of 0.5 cm$^2$/V.s and an on/off ratio of $\sim$10$^5$ was achieved in the micro-FETs with 50 $\mu$m channel width. Interestingly, on scaling down the ZnO channel width down to 100 nm, almost two orders of magnitude enhancement in the linear mobility was observed, which reached $\sim$33.75 cm$^2$/V.s. Such increment in the device performance was attributed to the formation of larger grains and thus reduction in the grain-boundary scattering. Six volatile organic compounds (VOCs) were sensed at room temperature using the direct-write EBL fabricated ZnO devices under UV sensitisation. As the surface-to-volume ratio increases with the decreasing channel width (from 50 $\mu$m to 100 nm), sensing response of the ZnO devices becomes more significant. Ppm level detection of various VOCs was observed; with a 25 ppm level Anisole detection being the lowest concentration. Additionally, using 100 nm device, detection of 10 ppm NO$_2$ was achieved at room temperature. The sensing response towards NO$_2$ was found to be increased with UV illumination and sensor temperature. This led to exhibit $\sim$171 % sensing response for a 2.5 ppm level of NO$_2$.

Researchers have tried to demonstrate the effectiveness of written teacher feedback over the course of the last sixty years, and the results are inconclusive. Many studies point to improvement on subsequent drafts as evidence of student improvement; however, this only indicates students' abilities to follow directions. It is not an indication of autonomous writing ability. This study demonstrates that with proper curriculum support high school students can develop intentional transferability (the autonomous, intentional transferring of writing skills to varied rhetorical situations) throughout the course of one academic year without receiving any teacher written feedback.