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Modern Portfolio Theory Combined With Magic Formula : A study on how Modern Portfolio Theory can improve an established investment strategy.Ljungberg, Axel, Högstedt, Anton January 2021 (has links)
This study examines whether modern portfolio theory can be used to improve the Magic Formula investment strategy. With the assets picked by the investment strategy we modify the portfolios by weighting the portfolios in accordance with modern portfolio theory. Through the process of creating efficient frontiers and weighting the portfolios differently we create two alternative portfolios each year. One portfolio that aimsfor maximum Sharpe ratio and one that aims for minimum variance. These weighted portfolios produce higher risk-adjusted returns consistently during the examined period of 2010-2020. We conclude that the Magic Formula can be improved by using modern portfolio theory.
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Development of a reliable and time-efficient digital production process of encrypted intelligent keys : Embedded systems and software developmentAlmario Strömblad, Fredrik, Svensson, Primus January 2022 (has links)
Smart keys are increasing in popularity due to the many benefits they bring. Access control and overview have never been more efficient than it is today. This thesis project automates the digital production of a new line of keys. Automating this production process improves the production in scalability, reliability, and efficiency. This report includes background research on critical components, methodologies to solve presented subproblems, the results of this project, and a discussion providing insight into the possible benefits of using an automated development line. This automation’s core elements are an integrated circuit holding a microcontroller, hardware components, and a graphical user interface. This project results in an automated production process capable of producing smart keys more efficiently than today. A report containing the most common errors using this production process and suggestions to improve scalability, reliability, and efficiency further. / De många fördelar smarta nycklar bidrar med gör att de snabbt ökar i popularitet. Åtkomst och översikt över tillgång har aldrig varit så effektivt som det är idag. Detta examensarbete automatiserar den digitala produktionen av en ny serie elektroniska nycklar. Genom att automatisera den här processen kommer produktionens skalbarhet, pålitlighet och effektivitet att öka. Den här rapporten innehåller bakgrundsundersökningar gällande kritiska områden för utvecklingen, metoder för att lösa problemställningar, projektets resultat samt en diskussion gällande möjliga fördelar av produktionsautomatisering. Grundelementen i den här automatiseringen är ett kretskort med en mikrokontroller, hårdvarukomponenter samt ett grafiskt användargränssnitt. Projektet resulterar i en produktionsprocess kapabel att producera elektroniska nycklar effektivare än tidigare möjligt samt en rapport innehållande de mest förekommande produktionsfelen relaterade till den automatiserade processen. Rapporten innehåller även förslag på förbättringar för att ytterligare öka skalbarhet, pålitlighet och effektivitet.
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Control Strategy for Energy Efficient Fluid Power Actuators : Utilizing Individual MeteringEriksson, Björn January 2007 (has links)
This thesis presents a solution enabling lower losses in hydraulic actuator systems. A mobile fluid power system often contains several different actuators supplied with a single load sensing pump. One of the main advantages is the need of only one system pump. This makes the fluid power system compact and cost-effective. A hydraulic load often consists of two ports, e.g. motors and cylinders. Such loads have traditionally been controlled by a valve that controls these ports by one single control signal, namely the position of the spool in a control valve. In this kind of valve, the inlet (meter-in) and outlet (meter-out) orifices are mechanically connected. The mechanical connection makes the system robust and easy to control, at the same time as the system lacks flexibility. Some of the main drawbacks are The fixed relation between the inlet and outlet orifices in most applications produce too much throttling at the outlet orifice under most operating conditions. This makes the system inefficient. The flow directions are fixed for a given spool position; therefore, no energy recuperation and/or regeneration ability is available. In this thesis a novel system idea enabling, for example, recuperation and regeneration is presented. Recuperation is when flow is taken from a tank, pressurized by external loads, and then fed back into the pump line. Regeneration is when either cylinder chambers (or motor ports) are connected to the pump line. Only one system pump is needed. Pressure compensated (load independent), bidirectional, poppet valves are proposed and utilized. The novel system presented in this thesis needs only a position sensor on each compensator spool. This simple sensor is also suitable for identification of mode switches, e.g. between normal, differential and regenerative modes. Patent pending. The balance of where to put the functionality (hardware and/or software) makes it possible to manoeuvre the system with maintained speed control in the case of sensor failure. The main reason is that the novel system does not need pressure transducers for flow determination. Some features of the novel system: Mode switches The mode switches are accomplished without knowledge about the pressures in the system Throttle losses With the new system approach, choice of control and measure signals, the throttle losses at the control valves are reduced Smooth mode switches The system will switch to regenerative mode automatically in a smooth manner when possible Use energy stored in the loads The load, e.g. a cylinder, is able to be used as a motor when possible, enabling the system to recuperate overrun loads The system and its components are described together with the control algorithms that enable energy efficient operation. Measurements from a real application are also presented in the thesis.
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Energy Modelling and Fairness for Efficient Mobile CommunicationVergara Alonso, Ekhiotz Jon January 2016 (has links)
Energy consumption and its management have been clearly identified as a challenge in computing and communication system design, where energy economy is obviously of paramount importance for battery powered devices. This thesis addresses the energy efficiency of mobile communication at the user end in the context of cellular networks. We argue that energy efficiency starts by energy awareness and propose EnergyBox, a parametrised tool that enables accurate and repeatable energy quantification at the user end using real data traffic traces as input. EnergyBox offers an abstraction of the underlying states for operation of the wireless interfaces and allows to estimate the energy consumption for different operator settings and device characteristics. The tool is used throughout the thesis to quantify and reveal inefficient data communication patterns of widely used mobile applications. We consider two different perspectives in the search of energy-efficient solutions. From the application perspective, we show that systematically quantifying the energy consumption of design choices (e.g., communication patterns, protocols, and data formats) contributes to a significantly smaller energy footprint. From the system perspective, we devise a cross-layer solution that schedules packet transmissions based on the knowledge of the network parameters that impact the energy consumption of the handset. These attempts show that application level decisions require a better understanding of possible energy apportionment policies at system level. Finally, we study the generic problem of determining the contribution of an entity (e.g., application) to the total energy consumption of a given system (e.g., mobile device). We compare the state-of-the-art policies in terms of fairness leveraging cooperative game theory and analyse their required information and computational complexity. We show that providing incentives to reduce the total energy consumption of the system (as part of fairness) is tightly coupled to the policy selection. Our study provides guidelines to select an appropriate policy depending on the characteristics of the system.
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A testbed implementation of energy efficient wireless sensor network routing protocols / Joubert George Jacobus KrigeKrige, Joubert George Jacobus January 2014 (has links)
Wireless Sensor Networks (WSNs) consist of Sensor Nodes (SNs) spatially removed
from one another, that can monitor a variety of environmental conditions. SNs then
collaboratively communicate the collected information to a central location, by passing
along the data in a multi-hop fashion. SN energy resources are limited and energy
monitoring and preservation in WSNs are therefore very important. Since multi-hop
communication takes place, the routing protocol used may have a significant effect on
the balanced use and preservation of energy in the WSN.
A significant amount of research has been performed on energy efficient routing in
WSNs, but the majority of these studies were only implemented in simulation. The
simulation engines used to perform these studies do not take into account all of the
relevant environmental factors affecting energy efficiency. In order to comment on the
feasibility of a routing protocol meant to improve the energy efficiency of a WSN, it is
important to test the routing scheme in a realistic environment.
In this study, a SN specifically designed to be used in an energy consumption ascertaining
WSN testbed was developed. This SN has a unique set of features which makes
it ideal for this application. Each SN is capable of recording its own power consumption.
The design also features a lithium battery charging circuit which improves the
reusability of the SN. Each node has a detachable sensor module and transceiver module
which enables the researcher to conduct experiments using various transceivers
and sensors. Twenty of these SNs were then used to form an energy consumption
ascertaining WSN testbed.
This testbed was used to compare the energy consumption of a Minimum Total Transmission
Power Routing (MTTPR) scheme to a shortest hop path routing scheme. The
results show that each SN’s transmission power setting dependant efficiency has a significant
effect on the overall performance of the MTTPR scheme. The MTTPR scheme
might in some cases use more energy than a shortest hop path routing scheme because
the transmission power setting dependant efficiency of the transceiver is not taken into account. The MTTPR scheme as well as other similar routing schemes can
be improved by taking the transceiver efficiency at different transmission power settings
into account. Simulation environments used to evaluate these routing schemes
can also be improved by considering the transceiver efficiency at different transmission
power settings. / MIng (Computer and Electronic Engineering), North-West University, Potchefstroom Campus, 2014
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A testbed implementation of energy efficient wireless sensor network routing protocols / Joubert George Jacobus KrigeKrige, Joubert George Jacobus January 2014 (has links)
Wireless Sensor Networks (WSNs) consist of Sensor Nodes (SNs) spatially removed
from one another, that can monitor a variety of environmental conditions. SNs then
collaboratively communicate the collected information to a central location, by passing
along the data in a multi-hop fashion. SN energy resources are limited and energy
monitoring and preservation in WSNs are therefore very important. Since multi-hop
communication takes place, the routing protocol used may have a significant effect on
the balanced use and preservation of energy in the WSN.
A significant amount of research has been performed on energy efficient routing in
WSNs, but the majority of these studies were only implemented in simulation. The
simulation engines used to perform these studies do not take into account all of the
relevant environmental factors affecting energy efficiency. In order to comment on the
feasibility of a routing protocol meant to improve the energy efficiency of a WSN, it is
important to test the routing scheme in a realistic environment.
In this study, a SN specifically designed to be used in an energy consumption ascertaining
WSN testbed was developed. This SN has a unique set of features which makes
it ideal for this application. Each SN is capable of recording its own power consumption.
The design also features a lithium battery charging circuit which improves the
reusability of the SN. Each node has a detachable sensor module and transceiver module
which enables the researcher to conduct experiments using various transceivers
and sensors. Twenty of these SNs were then used to form an energy consumption
ascertaining WSN testbed.
This testbed was used to compare the energy consumption of a Minimum Total Transmission
Power Routing (MTTPR) scheme to a shortest hop path routing scheme. The
results show that each SN’s transmission power setting dependant efficiency has a significant
effect on the overall performance of the MTTPR scheme. The MTTPR scheme
might in some cases use more energy than a shortest hop path routing scheme because
the transmission power setting dependant efficiency of the transceiver is not taken into account. The MTTPR scheme as well as other similar routing schemes can
be improved by taking the transceiver efficiency at different transmission power settings
into account. Simulation environments used to evaluate these routing schemes
can also be improved by considering the transceiver efficiency at different transmission
power settings. / MIng (Computer and Electronic Engineering), North-West University, Potchefstroom Campus, 2014
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Modular Field Programmable Gate Array Implementation of a MIMO TransmitterShekhar, Richa 10 1900 (has links)
ITC/USA 2010 Conference Proceedings / The Forty-Sixth Annual International Telemetering Conference and Technical Exhibition / October 25-28, 2010 / Town and Country Resort & Convention Center, San Diego, California / Multiple-Input Multiple-Output (MIMO) systems have at least two transmitting antennas, each generating unique signals. However some applications may require three, four, or more transmitting devices to achieve the desired system performance. This paper describes the design of a scalable MIMO transmitter, based on field programmable gate array (FPGA) technology. Each module contains a FPGA, and associated digital-to-analog converters, I/Q modulators, and RF amplifiers needed to power one of the MIMO transmitters. The system was designed to handle up to a 10 Mbps data rate, and transmit signals in the unlicensed 2.4 GHz ISM band.
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Cash vs. Stock Deals: Bidders' Performance in Tech and Non-tech M&A : Evidence from Mergers and Acquisitions in SwedenWulandari, Febi, Wang, Ji January 2015 (has links)
This paper researches the effects of choice of payment (cash and stock) and M&A type (technological and non-technological) on bidders’ performance. We investigate 500 events in Swedish market between 2005 and 2015. Moreover, we also control the size of firms and the value of takeovers. In this paper, we conduct an event study in order to generate abnormal returns for the bidders at and around the M&A announcement. This research generates statistically significant and positive abnormal returns for the bidders especially when deals are financed by shares. Moreover, we also find that the technological M&A brings about lower abnormal returns than non-technological M&A. When we control for payment choice in technological M&A, the result shows that technological M&A paid for in shares generates higher abnormal returns than technological M&A paid for in cash.
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Inomhusmiljö i miljöcertifierade skolbyggnader : En jämförande studie av upplevd inomhusmiljö i två miljöcertifierade och två konventionella skolbyggnaderSundström, Viktoria January 2016 (has links)
The purpose of this report was to find out if there were any differences in how the indoor environment was experienced in environmentally certified school buildings compared with similar conventional buildings. For that two certified school buildings, Vegaskolan in Vännäs and Hedlunda preschool in Umeå was compared with two conventional preschools in Umeå, Solbacken and Skattelden, in terms of how the indoor environment was experienced. This was done using a questionnaire and interviews. The results of the survey showed that Vegaskolan had the lowest percentage among the staff that was bothered by various environmental factors, while Hedlunda preschool had the largest share. Hedlunda also had the highest percentage amongst the staff with health problems. All four buildings surveyed, however, had smaller percentages who were disturbed by noise than preschools in general, and the environmentally certified buildings had an even lower percentage. If this is due to the certification is however difficult to say. Since there were more differences between the two certified buildings, it is difficult to draw general conclusions depending on the building type. Most of the differences showed in this study do not depend on the certification of the buildings, but of other causes. However the environmentally certified buildings are more complex than the conventional buildings, with more things that can go wrong. Therefore it requires more monitoring of the indoor environment after the building is put into use, as well as more information to operators and users in order to prevent adverse health effects, which seems to be the case at Hedlunda.
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Resource management in IP networksWahabi, Abdoul Rassaki 12 1900 (has links)
Thesis (MSc)--University of Stellenbosch, 2001. / ENGLISH ABSTRACT: lP networks offer scalability and flexibility for rapid deployment of value added lP
services. However, with the increased demand and explosive growth of the Internet,
carriers require a network infrastructure that is dependable, predictable, and offers
consistent network performance.
This thesis examines the functionality, performance and implementation aspects of
the MPLS mechanisms to minimize the expected packet delay in MPLS networks.
Optimal path selection and the assignment of bandwidth to those paths for minimizing
the average packet delay are investigated.
We present an efficient flow deviation algorithm (EFDA) which assigns a small amount
of flow from a set of routes connecting each OD pair to the shortest path connecting
the OD pair in the network. The flow is assigned in such a way that the network
average packet delay is minimized. Bellman's algorithm is used to find the shortest
routes between all OD pairs. The thesis studies the problem of determining the routes
between an OD pair and assigning capacities to those routes.
The EFDA algorithm iteratively determines the global minimum of the objective function.
We also use the optimal flows to compute the optimal link capacities in both single
and multirate networks. The algorithm has been applied to several examples and to
different models of networks. The results are used to evaluate the performance of the
EFDA algorithm and compare the optimal solutions obtained with different starting
topologies and different techniques. They all fall within a close cost-performance range.
They are all within the same range from the optimal solution as well. / AFRIKAANSE OPSOMMING: lP-netwerke voorsien die skaleerbaarheid en buigsaamheid vir die vinnige ontplooing
van toegevoegde-waarde lP-dienste. Die vergrote aanvraag en eksplosiewe uitbreiding
van die Internet benodig betroubare, voorspelbare en bestendige netwerkprestasie.
Hierdie tesis ondersoek die funksionaliteit, prestasie en implementering van die MPLS(multiprotokoletiketskakel)-
meganismes om die verwagte pakketvertraging te minimeer.
Ons bespreek 'n doeltreffende algoritme vir vloei-afwyking (EFDA) wat 'n klein hoeveelheid
vloei toewys uit die versameling van roetes wat elke OT(oorsprong-teiken)-
paar verbind aan die kortste pad wat die OT-paar koppel. Die vloei word toegewys
sodanig dat die netwerk se gemiddelde pakketvertraging geminimeer word. Bellman se
algoritme word gebruik om die kortste roetes tussen alle OT-pare te bepaal. Die tesis
bespreek die probleem van die bepaling van roetes tussen 'n OT-paar en die toewysing
van kapasiteite aan sulke roetes.
Die EFDA-algoritme bepaal die globale minimum iteratief. Ons gebruik ook optimale
vloeie vir die berekening van die optimale skakelkapasiteite in beide enkel- en multikoers
netwerke. Die algoritme is toegepas op verskeie voorbeelde en op verskillende
netwerkmodelle. Die skakelkapasiteite word aangewend om die prestasie van die EFDAalgoritme
te evalueer en dit te vergelyk met die optimale oplossings verkry met verskillende
aanvangstopologieë en tegnieke. Die resultate val binne klein koste-prestasie
perke wat ook na aan die optimale oplossing lê.
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