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Ledarskap i tv-såpans värld : tre hierarkiska nivåer i Rederiet / Leadership in the world of soapoperas : three hierarchical levels in RederietLund, Malin, Lundgren, Åsa January 2003 (has links)
Background: The description of different characters in soapoperas are often exaggerated to catch the viewers interest and to present an exiting content. The phenomenon that takes place in soapoperas can often relates to every-day- life-situations. The viewers should recognise them selves in the content, the imaginary situations and the characters should be normal but at the same time exaggerated and twisted to catch the viewers attention. This means that the characters in Rederiet should have connections to the real world and this makes it interesting to study how the different styels of leadership are descibed. Purpose: The purpose is to analyse and compare three choosen characters in the soapopera Rederiet, from existing leadership thoeries. To identify leadership on three hierarchical levels – head of machinery, superintendent and captain – and to analyse how leadership are descibed in the soapopera. Realization: The study is based on videotaped episodes of the soapopera Rederiet. Conclusion: The mediate illustrations can be compared to the scientific theories. The three managers are different from eachother. Leadership depends on the managers acting, in the soapopera and in real life. The mediate illustrations shows that leadership are different and dependent on personality and hierarchical position. This holds for Rederiet and for real organizations.
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Embodied Evolution of Learning AbilityElfwing, Stefan January 2007 (has links)
Embodied evolution is a methodology for evolutionary robotics that mimics the distributed, asynchronous, and autonomous properties of biological evolution. The evaluation, selection, and reproduction are carried out by cooperation and competition of the robots, without any need for human intervention. An embodied evolution framework is therefore well suited to study the adaptive learning mechanisms for artificial agents that share the same fundamental constraints as biological agents: self-preservation and self-reproduction. The main goal of the research in this thesis has been to develop a framework for performing embodied evolution with a limited number of robots, by utilizing time-sharing of subpopulations of virtual agents inside each robot. The framework integrates reproduction as a directed autonomous behavior, and allows for learning of basic behaviors for survival by reinforcement learning. The purpose of the evolution is to evolve the learning ability of the agents, by optimizing meta-properties in reinforcement learning, such as the selection of basic behaviors, meta-parameters that modulate the efficiency of the learning, and additional and richer reward signals that guides the learning in the form of shaping rewards. The realization of the embodied evolution framework has been a cumulative research process in three steps: 1) investigation of the learning of a cooperative mating behavior for directed autonomous reproduction; 2) development of an embodied evolution framework, in which the selection of pre-learned basic behaviors and the optimization of battery recharging are evolved; and 3) development of an embodied evolution framework that includes meta-learning of basic reinforcement learning behaviors for survival, and in which the individuals are evaluated by an implicit and biologically inspired fitness function that promotes reproductive ability. The proposed embodied evolution methods have been validated in a simulation environment of the Cyber Rodent robot, a robotic platform developed for embodied evolution purposes. The evolutionarily obtained solutions have also been transferred to the real robotic platform. The evolutionary approach to meta-learning has also been applied for automatic design of task hierarchies in hierarchical reinforcement learning, and for co-evolving meta-parameters and potential-based shaping rewards to accelerate reinforcement learning, both in regards to finding initial solutions and in regards to convergence to robust policies. / QC 20100706
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Från manskap till befäl : en studie om att ta steget inom samma verksamhetBrandt, Henry, Andersson, Gustav January 2013 (has links)
The aim of this work was to investigate how it is to move in hierarchy from crew to officer within the seafaring profession and how to be affected by this. How you are perceived by the crew when going from to represent a part of a system to represent a different part of the same system and if you are ready to assume the responsibilities of the new role entails? This is relevant and interesting as we will soon is facing at this transition. The work is based on a qualitative approach. The choice of this method gave the information needed for a perfect result. Interviews were conducted through personal meetings with active officers which also provided the opportunity to ask follow-up questions and the respondents were given the opportunity to share their experiences. The results showed that the transition from crew to command seems to be something individual from person to person but consistently has been the feeling that it is a major challenge of excitement and some nervousness. The largest portion prior to having been men from before is that it felt familiar with the safety procedures on board and to have a basic sense of security regarding departures and mooring, loading and unloading. Most felt that it was difficult to give orders to his old sailor colleagues but afterwards it felt more natural.
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Dynamic Cooperative Secondary Access inHierarchical Spectrum Sharing NetworksWang, Liping, Fodor, Viktoria Unknown Date (has links)
We consider a hierarchical spectrum sharing network consisting of a primary and a cognitive secondary transmitter-receiver pair, with non-backlogged traffic. The secondary transmitter may utilize cooperative transmission techniques to relay primary traffic while superimposing its own information, or transmit opportunistically when the primary user is idle. The secondary user meets a dilemma in this scenario. Choosing cooperation it can transmit a packet immediately even if the primary queue is not empty, but it has to bear the additional cost of relaying, since the primary performance needs to be guaranteed. To solve this dilemma we propose dynamic cooperative secondary access control that takes the state of the spectrum sharing network into account. We formulate the problem as a Markov Decision Process (MDP) and prove the existence of a stationary policy that is average cost optimal. Then we consider the scenario when the traffic and link statistics are not known at the secondary user, and propose to find the optimal transmission strategy using reinforcement learning. With extensive numerical evaluation, we demonstrate that dynamic cooperation with state aware sequential decision is very efficient in spectrum sharing systems with stochastic traffic, and show that dynamic cooperation is necessary for the secondary system to be able to adapt to changing load conditions or to changing available energy resource. Our results show, that learning based access control, with or without known primary buffer state, has close to optimal performance. / <p>QS 2013</p>
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Load reduction and invasive mussel effects on eutrophication dynamics in Saginaw Bay, Lake HuronCha, Yoon Kyung January 2011 (has links)
<p>Phosphorus load reduction and dreissenid invasion are the two most important factors that influence europhication dynamics in the Great Lakes. The 1978 amendments to the Great Lakes Water Quality Agreement (GLWQA) between the United States and Canada established target phosphorus loads for the lakes, leading to reductions in external phosphorus loading to the Great Lakes. With diminished phosphorus levels, further nutrient management was a minor concern until the proliferation of invasive dreissenid mussels. Dreissenid mussels were first documented in the Laurentian Great Lakes in the late 1980s. Zebra mussels (<italic>Dreissena polymorpha</italic>) spread quickly into shallow, hard-substrate areas; quagga mussels (<italic>Dreissena rostriformis bugensis</italic>) spread more slowly and are currently colonizing deep, offshore areas. These mussels have the potential to modify biogeochemical processes and food web structure, altering nutrient cycling and availability. Following the mussel invasion, cyanobacterial blooms and nuisance benthic algal growth have reappeared in many nearshore areas of the Great Lakes.</p><p>This dissertation characterizes long-term patterns of phosphorus loading and mussel populations for Saginaw Bay, and estimates the effects of load reductions and dreissenid invasion on several aspects of pelagic water quality, focusing on phosphorus flux and cycling in Saginaw Bay. Bayesian approaches were used to quantify the impacts of load reduction and mussel invasion, while at the same time addressing model parameter uncertainty and prediction uncertainty associated with long-term observational data. Annual total phosphorus load estimates suggest a decreasing trend until the late 1970s to early 1980s, reflecting the effectiveness of point source controls implemented pursuant to GLWQA. Despite the decrease, however, the annual loads have not likely met the 440 tonne yr-1 target established for Saginaw Bay. In 1990 zebra mussels were discovered in the bay and by 1992 they were widespread and peaked with densities of >30,000 m<super>-2</super>. Following the peak, mean densities dropped and modeling results predict that the density will reach equilibria at ~600 m<super>-2</super>. When mussels appeared, the proportion of tributary phosphorus retained in Saginaw Bay increased from ~0.5 to ~0.7, reducing phosphorus export to the main body of Lake Huron. The combined effects of increased phosphorus retention and decreased phosphorus loading have caused an ~60% decrease in phosphorus export from Saginaw Bay to Lake Huron. The analysis of long-term patterns of pelagic water quality highlights the sustained effects of mussel invasion on altering water quality parameters in Saginaw Bay; there was a consistent decrease in chlorophyll concentrations by ~46%, and total phosphorus concentrations by ~25%, and an increase in secchi depths by ~15% over ~20 year invasion of mussels. A comparison of chlorophyll-phospohrus relationship between pre- and post-invasion periods suggest the reduced chlorophyll yield for a given phosphorus concentration after the mussel invasion. Further, decreases in both total phosphorus and chlorophyll concentrations were found in the majority of 24 mussel-invaded US lakes in addition to Saginaw Bay, and modeling results predict less chlorophyll yields per unit phosphorus level that ranges from oligo- to mesotrophic conditions. All lines of evidence presented in the dissertation point to the important roles of load reductions and invasive mussels affecting eutrophication dynamics in lake ecosystems.</p> / Dissertation
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Haptic Image ExplorationLareau, David 12 January 2012 (has links)
The haptic exploration of 2-D images is a challenging problem in computer haptics. Research on the topic has primarily been focused on the exploration of maps and curves. This thesis describes the design and implementation of a system for the haptic exploration of photographs. The system builds on various research directions related to assistive technology, computer haptics, and image segmentation. An object-level segmentation hierarchy is generated from the source photograph to be rendered haptically as a contour image at multiple levels-of-detail. A tool for the authoring of object-level hierarchies was developed, as well as an innovative type of user interaction by region selection for accurate and efficient image segmentation. According to an objective benchmark measuring how the new method compares with other interactive image segmentation algorithms shows that our region selection interaction is a viable alternative to marker-based interaction. The hierarchy authoring tool combined with precise algorithms for image segmentation can build contour images of the quality necessary for the images to be understood by touch with our system. The system was evaluated with a user study of 24 sighted participants divided in different groups. The first part of the study had participants explore images using haptics and answer questions about them. The second part of the study asked the participants to identify images visually after haptic exploration. Results show that using a segmentation hierarchy supporting multiple levels-of-detail of the same image is beneficial to haptic exploration. As the system gains maturity, it is our goal to make it available to blind users.
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The Cognitive-affective and Behavioural Impact of Emotionally Focused Couple TherapyBurgess Moser, Melissa 21 August 2012 (has links)
Emotionally Focused Couple Therapy (EFT; Johnson, 2004) addresses relationship distress by facilitating the development of new patterns of interaction between partners. These new patterns of interaction are based on partners' vulnerable acknowledgement and expression of attachment needs. Partners' engagement in these new patterns of interaction is thought to improve their relationship-specific attachment bond. Although previous studies have shown EFT to result in excellent relationship satisfaction outcomes (Johnson, Hunsley, Greenberg & Schindler, 1999), research had yet clearly to demonstrate if and how EFT facilitates increases in partners' relationship-specific models attachment security over the course of therapy. To address this research gap, the current study employed Hierarchical Linear Modelling (HLM; Singer & Willet, 2003) to investigate the pattern of change in couples' (n=32) self-reported relationship satisfaction and relationship-specific attachment over the course of EFT. Couples reported significant linear increases in their relationship satisfaction and significant linear decreases in their relationship-specific attachment avoidance over the course of therapy. Couples who completed the blamer-softening therapeutic change event (n=16) demonstrated significant linear decreases in their relationship-specific attachment anxiety after completing this event. Decreases in relationship-specific attachment anxiety predicted increases in couples' relationship satisfaction over the course of therapy. Couples also demonstrated significant increases in the security of their pre-post-therapy relationship-specific attachment behaviour, as coded Secure Base Scoring System (Crowell, Treboux, Gao, Fyffe, Pan & Waters, 2002). The current study also used HLM (Singer & Willet, 2003) to examine how the completion of blamer-softening impacted softened couples' relationship-specific attachment anxiety, and whether the completion of blamer-softening had a similar impact on softened couples' relationship-specific attachment avoidance and relationship satisfaction. Softened couples reported an immediate increase in relationship satisfaction and immediate decrease relationship-specific attachment avoidance at the softening session. Further, softened couples' post-softening decreases in relationship-specific attachment anxiety were initially preceded by an increase at the softening session. These results provided an understanding of how EFT leads to increases in couples' relationship-specific attachment security. These results provide support for the use of attachment theory in the treatment of relationship distress, and also provide an illustration of how attachment can shift over the course of a therapeutic intervention.
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Efficient Virtual Network Embedding onto A Hierarchical-Based Substrate Network FrameworkGhazar, Tay 12 March 2013 (has links)
The current Internet architecture presents a barrier to accommodate the vigorous arising
demand for deploying new network services and applications. The next-generation architecture views the network virtualization as the gateway to overcome this limitation. Network virtualization promises to run efficiently and securely multiple dedicated virtual networks (VNs) over a shared physical infrastructure. Each VN is tailored to host a unique application based on the user’s preferences.
This thesis addresses the problem of the efficient embedding of multiple VNs onto a
shared substrate network (SN). The contribution of this thesis are twofold: First, a novel hierarchical SN management framework is proposed that efficiently selects the optimum VN mapping scheme for the requested VN from more than one proposed VN mapping candidates obtained in parallel. In order to accommodate the arbitrary architecture
of the VNs, the proposed scheme divides the VN request into smaller subgraphs, and
individually maps them on the SN using a variation of the exact subgraph matching
techniques.
Second, the physical resources pricing policy is introduced that is based on time-ofuse,
that reflects the effect of resource congestion introduced by VN users. The preferences of the VN users are first represented through corresponding demand-utility functions that quantify the sensitivity of the applications hosted by the VNs to resource consumption and time-of-use. A novel model of time-varying VNs is presented, where users are allowed to up- or down-scale the requested resources to continuously maximize their utility while minimizing the VNs embedding cost.
In contrast to existing solutions, the proposed work does not impose any limitations
on the size or topology of the VN requests. Instead, the search is customized according
to the VN size and the associated utility. Extensive simulations are then conducted to
demonstrate the improvement achieved through the proposed work in terms of network
utilization, the ratio of accepted VN requests and the SP profits.
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Examining Predictors of Change in Emotionally Focused Couples TherapyDalgleish, Tracy L. 05 April 2013 (has links)
Emotionally Focused Couple Therapy (EFT; Johnson, 2004) is an empirically validated approach to couple therapy that uses attachment theory to understand the needs and emotions of romantic partners. In EFT, relationship distress is conceptualized as resulting from negative affect, emotional disconnection, and unmet attachment needs. Although EFT is recognized as one of the most researched and effective approaches to couple therapy, little research has examined theoretically related characteristics of couples to changes in marital satisfaction throughout EFT. The present doctoral thesis examined this area of literature. Thirty-two couples were provided approximately 21 sessions of EFT. The goal of the first study was to identify intake characteristics related to change in marital satisfaction over the course of EFT. Couples completed self-report measures of marital satisfaction, attachment security, relationship trust, and emotional control at pre- and post-therapy and after each therapy session. Individuals higher on self-report attachment anxiety and higher levels of emotional control had greater change in marital satisfaction over the course of EFT. The goal of the second study was to examine intake levels of attachment security and its relationship to the occurrence of the blamer-softening event, a key change event in EFT, and changes in marital satisfaction. Results indicated that the occurrence of a blamer-softening event significantly predicted positive changes in marital satisfaction. Results also suggested that the occurrence of a softening event significantly moderated the relationship between attachment avoidance at intake and change in marital satisfaction from pre- to post-therapy. For couples who completed a blamer-softening event, partners with lower levels of attachment avoidance were more likely to have positive changes in marital satisfaction. However, this relationship was not evident for attachment anxiety. Overall, results from this thesis suggest that attachment security is a key characteristic of couple partners for therapists to consider when implementing EFT. Therapists may benefit from assessing attachment security at the start of therapy to help inform them of the emotion regulating strategies used by couple partners. This information may help therapists to tailor specific interventions such that couples may begin to develop more secure attachment bonds.
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Social Cohesion Analysis of Networks: A Novel Method for Identifying Cohesive Subgroups in Social HypertextChin, Alvin Yung Chian 23 September 2009 (has links)
Finding subgroups within social networks is important for understanding and possibly
influencing the formation and evolution of online communities. This thesis addresses
the problem of finding cohesive subgroups within social networks inferred from online
interactions. The dissertation begins with a review of relevant literature and identifies
existing methods for finding cohesive subgroups. This is followed by the introduction of the SCAN method for identifying subgroups in online interaction. The SCAN (Social Cohesion Analysis of Networks) methodology involves three steps: selecting the possible members (Select), collecting those members into possible subgroups (Collect) and choosing
the cohesive subgroups over time (Choose). Social network analysis, clustering and
partitioning, and similarity measurement are then used to implement each of the steps.
Two further case studies are presented, one involving the TorCamp Google group and the
other involving YouTube vaccination videos, to demonstrate how the methodology works
in practice. Behavioural measures of Sense of Community and the Social Network Questionnaire are correlated with the SCAN method to demonstrate that the SCAN approach
can find meaningful subgroups. Additional empirical findings are reported. Betweenness
centrality appears to be a useful filter for screening potential subgroup members,
and members of cohesive subgroups have stronger community membership and influence
than others. Subgroups identified using weighted average hierarchical clustering are consistent with the subgroups identified using the more computationally expensive k-plex analysis. The value of similarity measurement in assessing subgroup cohesion over time is demonstrated, and possible problems with the use of Q modularity to identify cohesive subgroups are noted. Applications of this research to marketing, expertise location, and information search are also discussed.
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