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A Balance between Testing and Inspections : An Extended Experiment Replication on Code Verification / Balans mellan Testning och InspektionerScott, Hanna E.T. January 2004 (has links)
An experiment replication comparing the performance of traditional structural code testing with inspection meeting preparation using scenario based reading. Original experiment was conducted by Per Runeson and Anneliese Andrews in 2003 at Washington State University. / En experiment-replikering där traditionell strukturell kod-testning jämförs med inspektionsmötesförberedelse användandes scenario-baserad kodläsning. Det ursprungliga experimentet utfördes av Per Runeson och Anneliese Andrews på Washington State University år 2003.
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Användarfall ur ett spårbarhetsperspektivThunberg, Hans January 2000 (has links)
I detta arbete har en undersökning genomförts angående hur spårbarhet upprätthålls vid användning av användarfall. Rapporten behandlar spårbarhet och användarfall separat för att belysa viktiga fakta inom båda områdena. Syftet med arbetet var att ta reda på hur olika tillvägagångssätt för att representera användarfall upprätthöll spårbarhet mellan olika krav, och mellan krav och dess ursprung. Informationen inom problemområdet samlades in genom en litteraturstudie. I undersökningen identifierades flera olika typer av spårbarhet, vilka sedan låg till underlag för identifiering av spårbarhet i användarfall. Undersökningen visade också att det finns flera olika sätt att representera användarfall, i allt från naturligt språk till formella diagram. Resultatet av undersökningen visade även att användningen av ett modelleringsspråk som Unified Modeling Language (UML), med inbyggda relationer och namnkonventioner, gjorde att spårbarhet kunde upprätthållas mellan olika krav, och mellan krav och dess ursprung. En begränsad spåbarhet identifierades i samband med att mindre formella representationer av användarfall använts.
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Scenario thinking and stochastic modelling for strategic and policy decisions in agricultureStrauss, P.G. (Petrus Gerhardus) 06 June 2010 (has links)
In 1985, Pierre Wack, arguably the father of modern scenario thinking, wrote the following: “Forecasts often work because the world does not always change. But sooner or later forecasts will fail when they are needed most: in anticipating major shifts…” (Wack, 1985: 73). The truth of this statement have again become apparent, first as the “food price crisis” played out during 2007 and 2008, and secondly as the current financial and economic crisis are playing out. Respected market commentators and analysts, both internationally and within South Africa, made all sorts of “informed predictions” on topics ranging from oil prices, interest rates, and economic growth rates to input costs and food prices. The problem is that none of these “respected views” and “informed predictions and estimates” became true within the period that was assigned to these predictions. In fact, just the opposite occurred: the unexpected implosion of the global economy and hence commodity markets. The result of the experts “getting it so wrong”, is that questions are being asked about the reliability of risk and uncertainty analysis. Even though the experts used highly advanced analytical techniques in analyzing the risks and uncertainties in order to formulate predictions and outlooks, both the “food price crisis” and the economic implosion were totally unanticipated. The same questions need to be asked in terms of risk and uncertainty analyses in agricultural economics. With agriculture experiencing a period of fundamental changes causing significant uncertainty, risk and uncertainty analyses in agriculture will need to move to the next level in order to ensure that policies and business strategies are robust enough to withstand these newly arising uncertainties. The proposed solution to this problem and therefore the hypothesis offered and tested by this thesis is to work with two techniques in conjunction without combining it when developing a view of the future. The two techniques used, namely intuitive scenario thinking and stochastic modelling are based on two fundamentally different hypotheses namely: the future is like the past and present (stochastic modelling), and the future is not like the past and present but is a result of combining current and unexpectedly new forces or factors (intuitive scenario thinking). The idea behind this stems from the philosophy of Socrates, whereby he postulated that the truth can never be fully known and therefore, when working with the truth, one needs to work with multi-hypotheses about the truth until all but one hypothesis can be discarded. This will then bring one closer to the truth, but never lead you to know the truth in full, since the truth can’t be known in full. Applying this idea means conjunctively using two techniques which are based on the two hypotheses about the future. From a literature review it was realised that two such techniques existed, namely, stochastic modelling and scenario thinking. Stochastic modelling, by its very nature, is based on the assumption that the future is like the past and present since historical data, historical inter-relationships, experience, and modelling techniques are used to develop the model, apply it, and to interpret its results. Scenario thinking on the other hand, and specifically intuitive logics scenario thinking, is based on the notion that the future is not like the past or present, but is rather a combination of existing and new and unknown factors and forces. At first the perceived problem with this idea was thought to exist in the problem of using both techniques in combination, since the two techniques are fundamentally different because of the fundamentally different assumptions on which they are based. The question and challenge was therefore whether these two techniques could be used in combination, and how? However, the solution to this problem was more elementary than what was initially thought. As the two techniques are fundamentally different, it implies that the two techniques can’t be combined because the two underlying assumptions can’t be combined. However, what is possible is to use it in conjunction without adjusting either technique. Rather, one would allow each technique to run its course, which at the same time leads to cross-pollination in terms of ideas and perspectives, where possible and applicable. The cross-pollination of ideas and perspectives will then create a process whereby ideas regarding the two basic assumptions on the future are crystallised and refined through a learning process, hence resulting in clearer perspectives on both hypotheses about whether the future will be like the past and present, or whether the future will be a combination of existing and new but unknown factors and forces. These clearer perspectives provide a framework to the decision-maker whereby the two basic hypotheses on the future can be applied simultaneously to develop strategies and policies that are likely robust enough to be successful in both instances. It also provides a framework whereby reality can be interpreted as it unfolds, which signals to the decision-maker which of the two hypotheses is playing out. This will assist the decision-maker in better perceiving what is in fact happening, hence what the newly perceived truth is in terms of the future, and therefore what needs to be done in order to survive and grow within this newly developing future, reality, or truth. The presentation of three case studies assists in testing the hypothesis of this thesis as presented in chapter one, and concludes that the hypothesis can’t be rejected. Hence, through the presentation of the case studies it is found that using scenario thinking in conjunction with stochastic modelling does indeed facilitate a more complete understanding of the risks and uncertainties pertaining to policy and strategic business decisions in agricultural commodity markets, through fostering a more complete learning experience. It therefore does facilitate better decision-making in an increasingly turbulent and uncertain environment. / Thesis (PhD)--University of Pretoria, 2010. / Agricultural Economics, Extension and Rural Development / unrestricted
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A Quality Guaranteed Video Dissemination Protocol over Urban Vehicular Ad Hoc NetworksLi, Yang January 2014 (has links)
Video dissemination over Vehicular Ad Hoc Networks (VANETs) is an attractive technology which supports many novel applications. Hence, the merit of this thesis has twofold. Firstly, we evaluate and compare three routing techniques and two error resilience techniques. We select a sender-based routing technique called SUV and compare it with the other two selected receiver-based routing techniques named REACT-DIS and CDS. The results, more specifically, show that the receiver-based solutions outperform the sender-based solution. In addition, only CDS method fulfils the general quality requirements as it is the best that reduces redundancy packets and covers the whole topology. The results also indicate that the video coding scheme, Interleaving, can fix the multiple consecutive packet losses and guarantee reliable video qualities over VANETs. Network Coding, however, fails to provide satisfactory video quality for urban scenarios. This study next combines the selected receiver based routing techniques and the two error resilience techniques. We find the best combination is Interleaving over CDS. Secondly, we design a quality guaranteed video dissemination protocol for urban VANETs scenarios. Based on our comparison result, our protocol selects the CDS and Interleaving as the routing and error resilient techniques. To fix the single packet loses caused by the topology’s intermittent disconnection and collisions, we propose a store-carry-broadcast scheme for the nodes to re-transmit the local buffer saved packets. The results, when compared to the selected techniques and combinations, show that our proposed protocol is the most efficient one in terms of packet delivery, delay, overhead and video quality.
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Life cycle environmental and economic sustainability assessment of micro-generation technologies in the UK domestic sectorGreening, Benjamin Paul January 2014 (has links)
This research has assessed the environmental and economic sustainability of domestic micro-generation technologies under UK conditions as both individual technologies and as part of a range of future energy supply scenarios for the domestic sector extending to 2050. A life cycle approach has been used for both environmental and economic assessment considering the relevant sustainability impacts, which include global warming potential, the depletion of fossil fuels, human toxicity and life cycle cost. The micro-generation technologies studied were selected on the basis of their ability to contribute to current and future energy supply and also their suitability under UK conditions. These technologies were micro-wind, solar photovoltaics, micro-combined heat and power, heat pumps and solar thermal water heating. The technologies were compared with one another and with the incumbent technologies, which were grid electricity and natural gas condensing boilers. Three journal papers have been published as a result of this research. The evaluation of micro-generation technologies on a life cycle basis indicated that despite reducing certain environmental impacts, all technologies increased at least one and as many as eight environmental impacts compared to their current fossil-fuel alternatives. All micro-generation technologies would reduce global warming and fossil fuel depletion compared to conventional technologies, highlighting their potential to contribute to energy policy goals. However, they cannot currently compete with conventional technologies for capital cost, although their life cycle costs – taking into account incentives from schemes such as Feed-in Tariffs – can be competitive. Considering both environmental and economic implications suggested that Stirling engine micro-combined heat and power is one of the most sustainable options for heat and electricity generation. The results also suggested that heat pumps should not be receiving incentives from the Government due to their poor environmental performance. Four potential future energy supply scenarios for the UK domestic sector were studied extending to 2050. The scenarios varied in terms of the level of effort made to improve the environmental and economic sustainability of the sector. Scenario 1 involved no further implementation of micro-generation beyond 2009, increasing energy demand and a grid electricity dominated by fossil fuels. In contrast, Scenario 4 portrayed a future where there is 1 micro-generation technology per dwelling, a 50% reduction in demand and almost complete decarbonisation of the grid mix. The results indicated that a huge transformation of the sector is required to achieve the 80% reduction in CO2 emissions by 2050. This would include halving energy demand, almost complete decarbonisation of grid electricity and the installation of a micro-generation unit in every dwelling. To conclude, despite the level of interest micro-generation is currently receiving, this work suggested their usage may not necessarily be as beneficial as some believe. Their use does reduce greenhouse gas emissions and fossil fuel consumption; however, to have any influence on energy policy goals this use would have to be widespread. Furthermore, reduced emissions will come at the expense of other environmental impacts. Finally, with a number of the technologies not yet cost competitive – even with incentives – the Government focus on measures to reduce demand and decarbonise the grid may prove to be a better option as this work suggested that energy policy goals could be achieved without high penetration of micro-generation.
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Scenario Development for the City of Stockholm Towards a Fossil Fuel Free City by 2050Giagkalos, Panagiotis January 2012 (has links)
The City of Stockholm’s energy and climate goals are analyzed and projected in several scenarios. Using the year 2015 as the baseline year, a database covering the energy performance and fuel use within the City is created. This starting point is used to project the performance of the City until the year 2050. The projection is made with the use of scenarios and the simulation software LEAP by formulating scenarios that combine ongoing, planned and conceivable measures. All these scenarios aim to the reduction of emissions with the long term aim to set the City of Stockholm a fossil fuel free city by 2050. Various paths can be followed towards that goal and these are analyzed and classified based on cost and applicability. According to the simulation of scenarios, the immediate action and the long-term planning are shown to play an essential role in achieving the City’s goals. In addition, the significance of policy, the behavioral aspect and the continuous gradual development are found to be three basic pillars towards the target that the City has set. Specifically, the City should focus on energy efficiency in both generation and utilization. Available technology can help to this direction at an affordable cost and with remarkable potential. However, in order to achieve the target of an entirely fossil fuel free city by the year 2050, the City of Stockholm needs to support a shift of transportation modes towards public transport. Currently, the transportation sector has a low share of clean fuels and is likely going to be the most challenging sector to affect. Among the challenges in the transportation sector comes the fact that there is always a given risk when trying to introduce a new dominant fuel, based on assumptions of future car fleets and volatility of markets. Biofuels may for instance lead to a shortage in the market with higher biofuel and food prices as a result while changing the entire vehicle fleet takes 20 years on average. The best possible scenario does demonstrate one possible path toward a fossil fuel free City of Stockholm 2050 by taking a number of aggressive actions. This does not account for possible new technologies nor changes in the economy at large.
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Risks and scenarios in the Swedish income-based pension systemvon Mentzer, Simon January 2015 (has links)
In this master thesis the risks and scenarios in the Swedish income-based pension system are investigated. To investigate the risks one has chosen to look at a vector autoregressive (VAR) model for three variables (AP-fund returns, average wage returns and inflation). Bootstrap is used to simulate the VAR model. When the simulated values are received they are put back in equations that describes real average wage return, real return from the AP-funds, average wage and income index. Lastly the pension balance is calculated with the simulated data. Scenarios are created by changing one variable at the time in the VAR model. Then it is investigated how different scenarios affect the indexation and pension balance. The result show a cross correlation structure between average wage return and inflation in the VAR model, but AP-fund returns can simply be modelled as an exogenous white noise random variable. In the scenario when average wage return is altered, one can see the largest changes in indexation and pension balance. / I det här examensarbetet (”Risker och scenarion i Sveriges inkomstgrundande allmänna pensionssystem) undersöks risker och scenarier i inkomstpensionssystemet. För att kunna undersöka riskerna har en vector autoregressive (VAR) modell valts för tre variabler (AP-fonds avkastning, medelinkomst avkastning och inflation). Bootstrap används för att simulera VAR modellen. När värden från simuleringarna erhållits kan dessa sättas in i ekvationer som beskriver real medelinkomst avkastning, real avkastning från AP-fonderna och inkomst index. Slutligen beräknas pensionsbehållning med simulerad data. Scenarierna utförs genom att en variabel i taget i VAR modellen störs. Sedan utreds hur denna störning påverkar resterande parametrar som beräknas. Detta görs för olika scenarion. I VAR modellen finns korrelationer mellan medelinkomst avkastning och inflation, men AP-fonds avkastning kan ses som vitt brus. De scenarier som har störst påverkan på indexeringen ¨ar då medelinkomst avkastningen ¨andras.
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A Comparative Study on Aggregation Schemes in Heterogeneous Federated Learning ScenariosBakambekova, Adilya 03 1900 (has links)
The rapid development of Machine Learning algorithms and a growing range of its applications, as well as an increasing number of Edge Computing devices, created a need for a new paradigm that would benefit from both fields. Federated Learning, which emerged as an answer to this need, is a technique that also solves privacy-related issues arising when large amounts of information are collected on many individual devices and being used for a Machine Learning model by sending only the local updates and keeping the data.
At the same time, Federated Learning heavily relies on the computational and communicational capabilities of the devices that calculate the updates and send them to the main server to be integrated into a global model using one or the other Aggregation Scheme, which is one of the most important aspects of the Federated Learning. Carefully choosing how to aggregate local updates can diminish the impacts present from a huge variety of devices.
Therefore, this thesis work presents a thorough investigation of the Aggregation Schemes and analyzes their behaviors in heterogeneous Federated Learning scenarios. It provides an extensive description of the main features of schemes studied, defines the evaluation criteria, presents the resource costs associated with computational and communicational resources of the devices, and shows a fair assessment.
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Layoff Characteristics and Layoff Agents' Cognitions: An Experimental StudyLin, Chia-Jung 01 May 2009 (has links) (PDF)
Organizational downsizing is a prevalent, cost-reduction corporate strategy that executives often use to deal with dynamic competitive environments. Several studies have examined the financial implications of downsizing by evaluating the relationship between downsizing strategies and organizational performance and/or profitability. Other researchers have focused upon the responses and behaviors of layoff victims, survivors, and managers as a result of downsizing. Relatively few studies however, have investigated the impacts of layoff characteristics on the cognitions of the managers who plan and implement organizational downsizing. It has been argued that the process of layoff implementation potentially generates dissonance for the layoff agents as a result of the requirement to perform actions that are inconsistent with their cognitions and beliefs concerning workplace norms and behaviors (Margolis & Molinsky, 2008; Parker & McKinley, 2008; Sronce & McKinley, 2006). This study builds upon Festinger's (1957) cognitive dissonance theory that individuals experiencing cognitive dissonance have motivation to adopt dissonance reduction strategies, such as changing their behaviors or their cognitions, in order to balance the conflict between their beliefs in managerial role and actions of implementing layoffs. Four hypotheses are proposed to compare responses among participants facing different layoff characteristics. More specifically, drawing upon the free-choice paradigm (Brehm, 1956) of cognitive dissonance theory (Festinger, 1957), I anticipate that the subjects who make a more difficult layoff decision under certain layoff circumstances will experience more cognitive dissonance and will be motivated to adopt more positive perceptions of downsizing as a dissonance-reduction method than those who make an easier layoff decision. To evaluate the above relationships, a two-by-two factorial between-subjects experiment with various layoff conditions was carried out to investigate the impacts of layoff attributes on layoff agency-induced cognitive dissonance and layoff agents' perceptions of downsizing. Multivariate Analysis of Covariance (MANCOVA) methods were performed with gender and family layoff victimhood as control variables. The analyses found supports for hypothesis 1 and 3. Namely, individuals who make more difficult layoff decisions tend to experience more cognitive dissonance. The results of this study draw attention to how different layoff attributes affect layoff agents' responses especially in terms of their cognitions.
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Personlighetsdragens benägenhet att sätta ett högt första pris i en förhandling.Bertilsson, Filip, Johansson, Elias January 2023 (has links)
Abstract Title: The tendency of personality traits to set a high first price in a negotiation. Level: Bachelor’s degree thesis, final assignment for bachelor’s degree in business administration. Authors: Filip Bertilsson and Elias Johansson. Supervisor: Lars-Johan Åge. Date: 2023 - June. Aim: The purpose of the study is to investigate the tendency of different personality traits to set a high first price in a negotiation, based on the five-factor model and the anchoring effect. Method: The study has been carried out using scenario-based interviews and a personality test. Each individual respondent was then interviewed individually using a semi-structured interview based on one question, as well as follow-up questions based on what the respondents answered. Result and conclusion: The study shows the tendency of different personality types to start high in a negotiation. The study resulted in people with extra low neuroticism being the personality trait that has the greatest tendency to start high in a negotiation. The extra low neurotic respondents had SEK 11,000 as the average value of their first price in the negotiation, which is a significant difference from the study's total average value of SEK 10,137.5. Contribution of the thesis: The study contributes to greater understanding of the correlation between the anchoring effect in negotiations and the personality types in the five-factor theory. The study contributes to an opportunity for a fairer negotiation situation for both parties. This applies if knowledge about the other party's personality traits can be suspected. Suggestions for future research: The main further research needed in the subject is a study with more respondents, as there were few respondents in this study and all levels within the personality traits were not represented. A suggestion for further research is that the studies focus on the influence of age. For example, a study on age range to see the difference, even minors could be included in that study. Future studies could also include more information regarding low anchors in negotiation. Key words: The anchoring effect, the big five theory, negotiation, interview, scenario
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