This thesis examines the initial and long-term market reactions following reversed profit warnings on the Nordic markets. Furthermore, it investigates if firm size and trading volume can explain the magnitude of the market reaction. The study is based on 118 reversed profit warnings announced on the Nordic markets during 2010-2019 applying an event study approach, measuring abnormal returns. To examine if firm size and trading volume affects the market reaction, this study uses a regression analysis to complement the event study. Results show a significant initial market reaction, confirming that the market is genuinely surprised by a profit warning. In accordance with the efficient market hypothesis, the market is also seen to correct its expectations based on the new information. The initial reaction is more substantial for smaller firms and higher trading volume is seen to increase abnormal returns. Our long-term results show a significant reversal in share price, indicating that there is an overreaction to reversed profit warnings. The long-term regression results show that neither firm size nor trading volume explain the reversal in share price.

Tropical forests are amongst the most important ecosystems in the world. It is also the biome estimated to experience the most rapid losses of habitats in the next 50 years, mainly due to anthropogenic exploitation. The Kakamega forest, western Kenya, is important both for conservation and human livelihood and is essential for peoples’ survival. The main threat to the forest’s subsistence is collection of firewood used for cooking. Energy-efficient cookstoves, with almost 50 % lower demand for firewood compared to traditional 3-stone-stoves, have been installed to ease the pressure on the forest. The present study evaluates the effect of utilizing energy-efficient cookstoves, installed during the project Stoves for Life (years 2010-2019), on the forest structure of the Kakamega forest, Kenya. This was done by quantifying forest structural and compositional differences, as well as occurrence of human made damage, within the Kakamega forest. Sampling was made in 59 plot locations, with varying numbers of energy-efficient cookstoves in the surrounding area. Results indicate that the stoves 1) promote recruitment of both pioneer and climax trees and 2) increase survival of fast-growing pioneer trees, 3) ease the pressure on preferred species used as firewood and 4) preserve important structural components such as woody debris found on the forest floor. Additionally, the growth of pioneer trees is potentially creating a climate suitable for later successional species to thrive and establish, potentially leading to forest maturation. However, future comparative studies should be conducted before any statement about the stoves’ effect on forest structure is made.

A Wireless Sensor Network (WSN) is a collection of tiny devices called sensor nodes which are deployed in an area to be monitored. Each node has one or more sensors with which they can measure the characteristics of their surroundings. In a typical WSN, the data gathered by each node is sent wirelessly through the network from one node to the next towards a central base station. Each node typically has a very limited energy supply. Therefore, in order for WSNs to have acceptable lifetimes, energy efficiency is a design goal that is of utmost importance and must be kept in mind at all levels of a WSN system. The main consumer of energy on a node is the wireless transceiver and therefore, the communications that occur between nodes should be carefully controlled so as not to waste energy. The Medium Access Control (MAC) protocol is directly in charge of managing the transceiver of a node. It determines when the transceiver is on/off and synchronizes the data exchanges among neighbouring nodes so as to prevent collisions etc., enabling useful communications to occur. The MAC protocol thus has a big impact on the overall energy efficiency of a node. Many WSN MAC protocols have been proposed in the literature but it was found that most were not optimized for the group of WSNs displaying very low volumes of traffic in the network. In low traffic WSNs, a major problem faced in the communications process is clock drift, which causes nodes to become unsynchronized. The MAC protocol must overcome this and other problems while expending as little energy as possible. Many useful WSN applications show low traffic characteristics and thus a new MAC protocol was developed which is aimed at this category of WSNs. The new protocol, Dynamic Preamble Sampling MAC (DPS-MAC) builds on the family of preamble sampling protocols which were found to be most suitable for low traffic WSNs. In contrast to the most energy efficient existing preamble sampling protocols, DPS-MAC does not cater for the worst case clock drift that can occur between two nodes. Rather, it dynamically learns the actual clock drift experienced between any two nodes and then adjusts its operation accordingly. By simulation it was shown that DPS-MAC requires less protocol overhead during the communication process and thus performs more energy efficiently than its predecessors under various network operating conditions. Furthermore, DPS-MAC is less prone to become overloaded or unstable in conditions of high traffic load and high contention levels respectively. These improvements cause the use of DPS-MAC to lead to longer node and network lifetimes, thus making low traffic WSNs more feasible. / Dissertation (MEng)--University of Pretoria, 2008. / Electrical, Electronic and Computer Engineering / MEng / Unrestricted

At present, an important task for Chinese governments at all levels is to save energy and reduce pollutant emissions. The task of buildings energy efficiency accounts for 21% in the 12th Five Year Plan which from 2011 to 2015. With the development of social economy，the energy shortage is serious day by day．The energy-conservation of buildings is a high relevant issue in China．There are a large capacity and a wide range of existing buildings in Qingdao among which the overwhelming majority is the non-energy-efficient buildings and the operate energy consumption are enormous．At Present, according to the related statistic，the energy efficient building area only accounts for 3% to 5% of the total building area newly increased in our country every year, while in such existing buildings in Qingdao ，most of them are highly energy-consuming, the energy consumption in buildings is about 100-350 kWh for each floor area of the whole year，which is 2 to 3 times of the energy consumption of the same area of energy efficient buildings．So we can say that whether could we promote the effective use of resources and energy in buildings is very important，which will finally determine whether could we and take the road to sustainable development． In respect of the application of the complicated systematic scientific conclusions，the thesis carries out the analysis of geographic and climate characteristics in Qingdao area and the research of current energy consumption． Based on the quantitative model analysis of environmental and economic benefits of implementation of energy efficient buildings in Qingdao in scenario k, promotion and implementation of energy efficient buildings can substantially reduce the current high environmental cost associated with energy consumption for heating and cooling in buildings in Qingdao. Emission including carbon dioxides, sulfur oxide, nitrogen oxides and ash can be reduced, it means that under the scenario k energy efficient buildings has an idea performance on reducing pollutant gas. At the same time, companied by the great environmental benefits, there are also substantial economic benefits. Barriers to energy efficiency in buildings in Qingdao, including political, economic, social and technological barriers are discussed in this thesis. According to the investigation and analysis about the present situation and factors affecting the implementation of energy efficient buildings in Qingdao, this thesis put forward recommendations from the aspects of environment, politics, economy, society and technology to improving energy efficient buildings in Qingdao.

The notion of the networked society is more than ever true nowadays. The Internet has a big impact on our daily lives. Network operators provide the underlying infrastructure and continuously deploy services in order to meet customer demands. The amount of data transported through operator networks is also increasing with the introduction of new high band width services and over the network content. That being said, operators, most often deploy or operate networks to meet these demands without any regard to energy-efficiency. As the price of electricity continues to grow,  tends to become a problem with serious implications. To solve this problem a trend towards more energy efficient networks has emerged. In this thesis, we investigate a way to facilitate the introduction of new energy efficiency paradigms for fixed networks. Towards this end, we investigate the energy efficiency schemes proposed up to now and select one that we believe is more realistic to deploy. Furthermore, we specify the inputs required for the selected “green” routing approach. Moreover, we study existing and new protocols that can provide basic network monitoring functionality that enables the acquirement of these inputs. In the end, a Software Defined Networking (SDN) approach is proposed to facilitate the development of energy-efficient aware networks. The details of a basic SDN monitoring application are presented from an abstract architectural point of view and three designs stemming from this basic architecture are discussed. The three designs are namely All_Flow, First_Switch and Port_FlowRemoved. The first two were implemented as steps towards understanding the full capabilities of performing monitoring in SDN enabled networks and provided useful input towards realizing the third one as a proof of concept. Their usage and faults are discussed as they can provide useful insight for possible future implementations. The Port_FlowRemoved is the design and implementation that is suggested as providing the most fitting results for the monitoring purpose at hand. This purpose is to retrieve the identified inputs for the selected “green” networking approach. The differentiation factor among the three designs is how they collect the required inputs from the network. A fast-prototype is created as a proof of concept in order to validate the proposed architecture and thus empower the validity of the idea.

The efficient portfolios for the period 1993 – 2010 based on IPD data have a major portfolio weight in residential properties in the three largest regions Stockholm, Gothenburg and Malmo. The portfolio with the highest risk adjusted return (measured as the highest Sharpe-ratio) combines a large portfolio weight in residential properties with a small weight in industrial properties. During the time period of 2005 – 2010 a majority of the listed real estate companies held a real estate portfolio far below the efficient frontier based on the corresponding IPD data. These companies can increase their total return without taking on any more risk by using the concept of diversification. When including all available diversification categories two out of seven companies can be said to have an efficient real estate portfolio. When we excluded the outperforming residential asset class, however, none of the companies’ portfolios were in fact efficient. The real estate market is inefficient and thus results in the IPD data being less useful as it is based on transactions occurring in this inefficient market. Investors can, in this market, easily find properties with another risk and return profile than what IPD indicates is the market risk and return for a particular property type in a certain region. The inefficiency of the market, together with the IPD data being less useful, thus makes it difficult for the companies to focus on diversification in their investment strategy. Moreover, there are several reasons that explain the discrepancy between the actually held listed real estate portfolios and the optimal portfolio based on IPD data. Since each property is heterogeneous and possesses unique risks, investors are not able to accurately quantify the risk of each investment and thus rely more on their gut feeling. This also results in investors focusing on single investment opportunities rather than looking at all investments from a portfolio perspective.

In a world that is slipping towards a global energy crisis as a result of a heavy dependence on depleting fossil-based fuels, investment in projects that promote energy efficiency will have a strong return on investment not only economically but also socially & environmentally. Firms will directly save significant amounts of money on their energy bills and besides, contribute to slowing down the environmental degradation & global warming by diminishing their carbon footprint. In the global contest to achieve high levels of energy efficiency, IT sector is no exception and telecommunication companies have developed new approaches on how to develop more efficient data centers and cooling systems in the past decades. This paper describes an ambitious project carried out by TeliaSonera to develop a highly-energy-efficient cooling approach for data centers called "Green Room". It is important to realize that Green Room approach is not specifically limited to data centers. It is designed to support any sort of “technical site” in need of an efficient cooling system. As a result, the word “datacenter” repeatedly used in this paper is expandable to a huger category of technical sites. As the hypothesis, Green Room was expected to generate appropriate temperature level accompanied with effectual steady air flow inside the room while using considerably lower amount of electricity compared with other cooling methods in the market. To begin with, an introduction is given to familiarize the readers with the concept of "data center" and immediately preceded a concise discussion in Chapter 2 providing convincing reasons to promote energy-efficient projects like Green Room from economic, social and environmental points of view. The chapter is complemented by a comprehensive part attached to this paper as Appendix I. In Chapter 3, the different cooling approaches currently available for datacenters is looked into. Chapter 4 describes how it is possible to assess the efficiency of a data center cooling system by introducing critical values such as PUE (power usage effectiveness) and COP (Coefficient of performance). Understandably, it is of great significance to determine how accurate the measurements carried out in this project are. Chapter 5 provides useful information on measurements and describes uncertainty estimation of the obtained results. Chapter 6 explains the test methodology and continues by touching on the components of Green Room and their technical specifications. Subsequently, it compares the Green Room approach to other cooling systems and identifies five major differences making the Green Room a distinctive cooling method. Chapter 7 explains the measurement requirements from the point of view of sensors, discusses the calibration process and finally represents the uncertainty calculations and their results. Chapter 8 broadly describes the five different categories of 25 independent tests carried out within a period of almost two weeks. It provides the readers with all the necessary details for each test and includes thorough description of conditions, numerical results, calculations, tables, charts, graphs, pictures and some thermal images. Ultimately, the last two chapters summarize the results of this project and assess its degree of success based on the hypothesis of this paper. Consequently, a number of questions have been raised and relevant suggestions made to modify this approach and improve the results. Surprisingly, the values obtained for efficiency of this cooling system are as expected. However, some part of calculations to achieve the total power load of the whole cooling production system is based on estimations acquired from software simulations. Overall, this is considered as a successful project fulfilling the primary expectations of the founders.

A Monte Carlo light transport simulation is used in scattering-aware color 3D printing pipeline (Elek et al. [2017], Sumin et al. [2019]) to drive an iterative optimization loop. Its purpose is to find a material arrangement that yields the closest match in terms of surface appearance towards a target. As the light transport prediction takes up about 90% of the time it poses a significant bottleneck towards a practical application of this technology. The dense volumetric textures also require a lot of memory. Explicitly simulating every light interaction is particularly challenging in the setting of 3D printouts due to the heterogeneity, high density and high albedo of the media. In this thesis, we explore existing volumetric rendering techniques (Křivánek et al. [2014], Herholz et al. [2019]) and finally engineer a customized estimator for our setting, improving the performance considerably. Additionally, we investigate various storage solutions for the volumetric data and successfully reduce the memory footprint. All the algorithms are available in the form of Mitsuba renderer plugins.

The focus of this thesis is to analyze the management of supplier relationships in a supply chain and develop cost-effective processes for manufacturing of a finished product at a global company in Sweden. The study was initiated when the application of literature was of interest to one of the company's products that is under development. So far, the company's great focus has been on developing the product and getting as close to the finished product as possible. Equal focus has not yet been focused on managing suppliers and on defining the processes that arise after the finished product. The intention has been to facilitate decision-making in supplier management and manufacturing that will arise when the prototype will become a finished product and will be launched on the market. The aim for this study is to analyze the value chain in order to develop and check various production facilities to create opportunities for cost savings. -          RQ1. How does a good manufacturing strategy help in developing cost efficient products? -          RQ2. What are the challenges in developing a value chain containing several external suppliers? The approach applied in the study has been a review of scientific literature that provides a basis for answering the purpose and the questions that have been created. Data collected from the literature have been critically reviewed and adapted based on the purpose of the work and the empirical findings collected from the company. Data collected from the company in the form of interviews and observations have been regularly analyzed. The differences and similarities that exist between the empirical data and the literature have been elucidated by adapting the analysis to a pattern. The analysis provided a basis for the results where the development of two different concepts that can be used as an approach in the future could be created. The concepts were created and analyzed based on the company's prerequisites for applicable solutions. The results from the analysis were then summarized in results and recommendations with the categories: Value Stream Map, Hypothetical Production Line and Recommendations related to the modules of the product. These categories will facilitate decision-making regarding the choice of production in the future. Concepts that will facilitate decision-making for economic factors and process factors have also been developed as a “guideline” for approaches to supplier management and management of financial aspects.

In this thesis the relationship between company performance and top management stock ownership in the Swedish market was examined. As well as conducting research on the influence real earnings management has on company performance, and how real earnings management relates to the top management stock ownership. The study was based on a quantitative approach with secondary data that was retrieved from Eikon Refinitiv database, where the data stretched back from 2018-2020. This research found no clear relationship between the main concepts under investigation, that is stock ownership of top management and stock returns. The authors explain this by the sampling method in this research only include companies with share holdings. Furthermore, compared to other studies looking this research considers multiple market capitalizations who may operate differently. Finally, there is a suspicion in the field of research that the relationship between the two is not of a linear nature as such a linear methodology will not find any clear results. In conclusion, this research could be added to the list that does not find a relationship between the above stated variables to the literature which could further be applied to the Swedish market. In terms of real earnings management, a strong negative influence was found on share returns. The authors suggest that this finding can be used as a basis to form investment strategies through monitoring the occurrence of REM to predict when insiders are going to buy and sell. Through pursuing this strategy, it may be possible to create superior return as this study found support for the semi-strong form of market efficiency. Unfortunately, this study found no clear guidance of resolving agency issues. Rather it was concluded that shareholdings in the top management does not resolve agency problems given the occurrence of REM. The management most likely benefit from this through trading the company stock. However, further investigation on the topic should be conducted as it seems that alignment using holdings become more or less effective at certain levels of management share ownership. Furthermore, the notion that American ways of agency alignment may not be appropriate in the Swedish market was considered but no clear conclusion could be made in this research.