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The main purpose for an aggressive investor is to maximize the return in theinvestments. But in order to do so the risk should be taken into consideration.In this thesis, we utilize Markowitz portfolio theory, one of the standard modelsfor maximizing return while considering risk. The model allows the investorto balance risk tolerance and expected return on the stock market based onhistorical data. Simply put, the goal is to allocate capital to stocks in a mannerthat maximizes expected return while considering risk. The tested cases involvedmodels utilizing historical data from five and ten years ago, respectively. Theresulting allocation distribution of these portfolios depended on the varianceconstraint and, to a large extent, on how many years of historical data were used.These results emphasize the significance of data in portfolio optimization.

The situation in Sweden in regards to school libraries has been extensively discussed under quite some time. The discussion intensified when the school library got mentioned in the Swedish education act in 2011 stating that all pupils in Swedish schools should have access to a school library. However, it is far from the case in Sweden today. The aim of this study is to create and contribute knowledge about school district managers perception of the Swedish education act regarding the school library and how they work to implement this in the schools in their district. In order to do this, five semi-structured interviews were conducted with five school district managers in five Swedish municipalities. The transcript from these interviews were analyzed using qualitative content analysis structured by concept from implementation theory. These concepts focus on the design of the intervention (the education act), the executor (the school district managers) and the context. These concepts is further analyzed with aspect of the school districts managers will, understanding and ability to implement the educational act. The result shows that the school district managers find the educational act indistinct regarding what is meant with” access to” and” school library”. It also shows that this indistinctness allows the school district managers to form their own picture of what is meant with these words and that these pictures form how they work to implement the educational act and what their role is in the implementation.

In this work, we demonstrate the offline FPGA realization of both recurrent and feedforward neural network (NN)-based equalizers for nonlinearity compensation in coherent optical transmission systems. First, we present a realization pipeline showing the conversion of the models from Python libraries to the FPGA chip synthesis and implementation. Then, we review the main alternatives for the hardware implementation of nonlinear activation functions. The main results are divided into three parts: a performance comparison, an analysis of how activation functions are implemented, and a report on the complexity of the hardware. The performance in Q-factor is presented for the cases of bidirectional long-short-term memory coupled with convolutional NN (biLSTM + CNN) equalizer, CNN equalizer, and standard 1-StpS digital back-propagation (DBP) for the simulation and experiment propagation of a single channel dual-polarization (SC-DP) 16QAM at 34 GBd along 17×70 km of LEAF. The biLSTM+CNN equalizer provides a similar result to DBP and a 1.7 dB Q-factor gain compared with the chromatic dispersion compensation baseline in the experimental dataset. After that, we assess the Q-factor and the impact of hardware utilization when approximating the activation functions of NN using Taylor series, piecewise linear, and look-up table (LUT) approximations. We also show how to mitigate the approximation errors with extra training and provide some insights into possible gradient problems in the LUT approximation. Finally, to evaluate the complexity of hardware implementation to achieve 200 G and 400 G throughput, fixed-point NN-based equalizers with approximated activation functions are developed and implemented in an FPGA.

Under mitt tredje och sista år på kandidatutbildningen med musikinriktning har jag valt att fokusera på att bli bättre på att komponera solon utförda på elbas. Detta gav mig tillfället att verkligen fördjupa mig i stycken som jag tycker om och som samtidigt kunde ge mig en bättre förståelse för elbasens språk och roll som solist. Detta har även bidragit till att göra mig till en bättre musiker. Syftet med detta examensarbtete är att uppnå en fördjupad förståelse för vilka beståndsdelar som finns i ett musikaliskt övertygande solo för att sedan kunna applicera denna förståelse på elbasen och ge dem en personlig form. Jag har valt att analysera tre solon av tre olika musiker varav två av dem är improviserade solon som är utförda på elbas och ett av dom är ett skrivet solo som är utfört på synth. Jag har delat upp dessa solons analyser i takter om fyra eller två där jag har kollat in parametrar som till exempel: register, rytm, skalor som används, underdelning m.m. Målet var sedan att försöka skriva varsitt solo i samma anda som de solon jag analyserat men samtidigt krydda dessa på mitt eget sätt. Detta arbete har resulterat i tre egenkomponerade solon av olika karaktär med inspiration taget från de tre analyserade solona. Jag har börjat se nya vägar i mitt basspel och blivit mycket mer medveten om vikten av att ha en bra melodi. Min främsta utveckling har varit att jag börjat fokusera på mer på ackordstoner och gått ifrån att bara spela pentan, börjat jobba mer med fras-upprepning samt att använda mig av hela basens register.

This study aims to provide an increased understanding of sustainability in general and recycling as well as re-use in particular. The study revolves around a literature study, a case study and an interview study. The literature study paints a background, the interview study provides a situational picture and the case study an illustration of possible environmental savings. In the background, the global goals are highlighted together with the Sustainable Development Goals (Agenda 2030), as well as how these can be linked to the EU's taxonomy. The taxonomy provides certain requirements, which if met can provide beneficial financing. The taxonomy can be seen as a tool to prioritize sustainable development. After this, the work narrows to Sweden's own goals and ambitions. One way to achieve these goals is to reduce the construction and real estate sector's climate impact. One way forward to do this is to increase the progression on recycling and re-use of building materials, as well as building parts. The literature study presents a method for a re-use inventory. Also, how the work to promote re-using can look like in the various stages of construction. In the interview study, relevant actors are given space to give their views on issues concerning challenges, costs, collaborations, and materials within the framework of sustainability, re-using and recycling. The materials that the study examines are selected with the reference object in mind. The parts studied are the building’s facade and frame, since these are where the large volumes of material lie. The facade of the reference object consists of brick and the frame is of concrete. A background and description of the properties of these materials are reported. Under the calculation part, the volumes of the reference object and its CO2-eq emissions are reported in kg. A comparison is made between a scenario without recycled and re-used material and a scenario with recycled and re-used material. Everything is ended wit

Few-mode fibers and coupled-core multi-core fibers are attractive transmission media for space-division multiplexed transmission systems as they enable a high spatial channel multiplicity whilst sustaining the current standard cladding diameter. This paper compares space-division multiplexed recirculating loop transmission using either a 3-mode few-mode fiber or a 3-core coupled-core multi-core fiber. After analyzing the spectral attenuation properties of both fibers, we investigate the wavelength and transmission distance dependence of the transmission channel characteristics. We find that the channel memory length is shorter and mode-dependent loss is lower in the coupled-core multi-core fiber, which can be attributed to the fundamental mode-structure differences between the two fiber types. This leads to a higher data rate at similar transmission distance for the coupled-core multi-core fiber.

We investigate high-throughput, multi-band transmission in a 4-core multi-core fiber (MCF) with the same 125 mu m cladding diameter of standard single-mode fiber (SMF). A single wideband comb source is used to transmit up to 561 wavelength channels with 25 GHz spacing over a 120 nm bandwidth in S, C, and L bands. We demonstrate a maximum decoded throughput of 610 Tb/s in PDM-256QAM and PDM-64QAM signals over a 54 km fiber, transmitting more than 155 Tb/s in a single core and measuring a per-core average throughput exceeding record transmission demonstrations in SMF. In addition, we use noise loading measurements to characterize the achievable signal quality across the wideband transmitter. These results show that a single comb source can enable high-spectral efficiency modulation over wide bandwidths and further that low-core count homogeneous MCF technology can offer the same transmission performance as single-mode fibers without sacrificing mechanical reliability, and still offering the benefits of shared resources and greater efficiency that drives SDM technologies., QC 20210330

We demonstrate transmission of 368-WDM-38-core-3-mode x 24.5-GBaud 64- and 256-QAM signals over 13 km. Record data-rate and spectral-efficiency of 1158.7 b/s/Hz were enabled by a low DMD 38-core-3-mode fiber with high uniformity amongst cores., SyskonpostNot duplicate with DiVA 1592493QC 20201203

We demonstrate 596.4 Tb/s over a standard cladding diameter fiber with 4 single-mode cores, using a single wideband optical comb source to provide 25 GHz spaced carriers over 120 nm range across S, C and L bands. OFC 2020, QC 20201112

We describe a series of optical transmission experiments based around single-mode, multi-core fiber (MCF) amplified with 19-core, C+L band erbium-doped fiber amplifier (EDFA). The cladding-pumped amplifier uses two multi-mode pumps in each of C and L band to provide gain bandwidth over more than 75 nm. For recirculating transmission of PDM-16QAM signals on 345 wavelength carriers between 1530.52 nm and 1605.52 nm, we measure 0.715 Pb/s transmission over a distance of 2009 km (64 recirculations), equivalent to a throughput-distance product of 1.44 exabit/s x km. Next, using PDM-QPSK modulation, we investigate trans-oceanic transmission distances, measuring throughputs of 18.6 Tb/s and 14.5 Tb/s in 2 cores after 255 recirculations, a distance of 8007 km. Further, we evaluate the combined EDFA and fiber crosstalk penalties showing a core and wavelength dependence in agreement with previous MCF crosstalk measurements. These results demonstrate the potential of high core-count EDFAs to combine both high capacity transmission over transoceanic distances with benefits of SDM integration., QC 20200330