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Cache-Oblivious Searching and Sorting in MultisetsFarzan, Arash January 2004 (has links)
We study three problems related to searching and sorting in multisets in the cache-oblivious model: Finding the most frequent element (the mode), duplicate elimination and finally multi-sorting. We are interested in minimizing the cache complexity (or number of cache misses) of algorithms for these problems in the context under which the cache size and block size are unknown.
We start by showing the lower bounds in the comparison model. Then we present the lower bounds in the cache-aware model, which are also the lower bounds in the cache-oblivious model. We consider the input multiset of size <i>N</i> with multiplicities <i>N</i><sub>1</sub>,. . . , <i>N<sub>k</sub></i>. The lower bound for the cache complexity of determining the mode is Ω({<i>N</i> over <i>B</i>} log {<i>M</i> over <i>B</i>} {<i>N</i> over <i>fB</i>}) where ƒ is the frequency of the mode and <i>M</i>, <i>B</i> are the cache size and block size respectively. Cache complexities of duplicate removal and multi-sorting have lower bounds of Ω({<i>N</i> over <i>B</i>} log {<i>M</i> over <i>B</i>} {<i>N</i> over <i>B</i>} - £{<i>k</i> over <i>i</i>}=1{<i>N<sub>i</sub></i> over <i>B</i>}log {<i>M</i> over <i>B</i>} {<i>N<sub>i</sub></i> over <i>B</i>}).
We present two deterministic approaches to give algorithms: selection and distribution. The algorithms with these deterministic approaches differ from the lower bounds by at most an additive term of {<i>N</i> over <i>B</i>} loglog <i>M</i>. However, since loglog <i>M</i> is very small in real applications, the gap is tiny. Nevertheless, the ideas of our deterministic algorithms can be used to design cache-aware algorithms for these problems. The algorithms turn out to be simpler than the previously-known cache-aware algorithms for these problems.
Another approach to design algorithms for these problems is the probabilistic approach. In contrast to the deterministic algorithms, our randomized cache-oblivious algorithms are all optimal and their cache complexities exactly match the lower bounds.
All of our algorithms are within a constant factor of optimal in terms of the number of comparisons they perform.
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Neuropsychology of Semantic Memory: Theories, Models, and TestsLaurila, Linda January 2007 (has links)
<p>Semantic memory is part of the long-term memory system, and there are several theories concerning this type of memory. Some of these will be described in this essay. There are also several types of neuropsychological semantic memory deficits. For example, test results have shown that patients tend to have more difficulties naming living than nonliving things, and one probable explanation is that living things are more dependent on sensory than on functional features. Description of concrete concepts is a new test of semantic memory, in which cueing is used, both to capture the maximum performance of patients, and to give insight into the access versus storage problem. The theoretical ideas and empirical results relating to this new test will be described in detail. Furthermore, other tests of semantic memory that have been commonly used will also be briefly described. In conclusion semantic memory is a complex cognitive system that needs to be studied further.</p>
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The benefits of advertising status : what conspicuous consumption buys women / What conspicuous consumption buys womenCloud, Jaime Marie 18 July 2012 (has links)
The primary objectives of the current research were to (1) test the effectiveness of conspicuous consumption as a status-enhancement tactic and (2) examine access to material resources as an interpersonal benefit that incentivizes status striving behavior. The studies that follow investigated the status striving motivations of both men and women; however, this research endeavor was primarily designed to address the paucity of research on female status. In Study 1, a nation-wide sample of participants perceived target women to be higher status when they were depicted conspicuously consuming than when not. Several individual difference variables that predict conspicuous consumption were also identified, many of which related to the attainment of high status. In Studies 2 and 3, conspicuous consumption was shown to increase perceptions of status in face-to-face interactions, further supporting the status signaling function of conspicuous consumption. Study 3 utilized a Dictator Game methodology to test the prediction that participants would share more of a monetary allotment with confederates who were conspicuously consuming than with those who were not. Results indicated that conspicuous consumption did not increase generosity except in male participants who shared more of a monetary allotment with conspicuous consumers, particularly those of the same sex. This sex-specific result is discussed in light of the possibility that conspicuous consumption signals a type of status that is particularly relevant to men (i.e., economic status). In conclusion, I consider the different pathways by which high status individuals receive increased access to resources. / text
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En studie om förutsättningar för ledarskap i kunskapsintensiva verksamheter / A study about conditions for leadership in knowledge-intensive firmsEkström, Cecilia, Sandberg, Niklas January 2013 (has links)
Title: A study about conditions for leadership in knowledge-intensive firms. Authors: Cecilia Ekström and Niklas Sandberg Keywords: Leadership, knowledge-intensive firm, hierarchies, followers. Background: Leadership is becoming one of our greatest social myths and is considered a total solution for many problems that occur in an organization. The view of leadership is usually from a top-down perspective, which contributes to an often underestimated view of the follower. Just as it is important to understand the leader's view of leadership, it is important to understand how employees view the structure from which the leader derives its legitimacy. The existing conditions in knowledge-intensive firms, such as autonomy, place special demands on the formal leadership. Purpose: The purpose of this study takes an employee perspective, to understand what the conditions are for formal leadership in knowledge-intensive firms. Method: A qualitative research method was used and empirical material was collected through interviews with employees in knowledge-intensive firms. The empirical material was analyzed by the respondents’ mental images which were set against the theoretical framework of the thesis. Conclusions: The conditions for formal leadership in knowledge-intensive firms make it advantageous to have a leader with a withdrawn role. It is about taking advantage of the employees’ cutting edge knowledge of the work and to support and develop the employees. The leader needs to be aware that it is important for employees to be heard and that questioning is a way to develop the organization. The leader also needs to be aware that even employees in knowledge-intensive firms, which seemingly are very independent, need frameworks to relate to that distributes roles and responsibilities. / Titel: En studie om förutsättningar för ledarskap i kunskapsintensiva verksamheter. Författare: Cecilia Ekström och Niklas Sandberg Nyckelord: Ledarskap, kunskapsintensiva verksamheter, hierarkier, följare. Bakgrund: Ledarskap håller på att växa till en av vår tids största sociala myter och anses som en helhetslösning för många problem som uppstår i en organisation. Synen på ledarskap utgår oftast ifrån ett uppifrån-och-ner perspektiv vilket bidrar till att följarnas roll ofta undervärderas. På samma sätt som det är viktigt att förstå ledarens syn på ledarskap är det viktigt att förstå hur medarbetarna ser på den struktur varifrån ledaren hämtar sin legitimitet. De förutsättningar som finns i kunskapsintensiva verksamheter, till exempel autonomi, ställer särskilda krav på det formella ledarskapet. Syfte: Syftet med uppsatsen är att genom ett medarbetarperspektiv skapa förståelse för vilka förutsättningar som finns för formellt ledarskap i kunskapsintensiva verksamheter. Metod: En kvalitativ forskningsmetod har använts och empirimaterialet samlades in genom intervjuer med anställda i kunskapsintensiva verksamheter. Empirimaterialet har analyserats genom att respondenternas mentala bilder har ställts mot uppsatsens teoretiska referensram. Slutsatser: Förutsättningarna för formellt ledarskap i kunskapsintensiva verksamheter gör det fördelaktigt att ledaren har en tillbakadragen roll. Det handlar om att ta vara på medarbetarnas spetskunskaper i arbetet samt stötta och utveckla medarbetarna. Ledaren behöver vara medveten om att det är viktigt för medarbetarna att få komma till tals och att ifrågasättande är ett sätt att utveckla organisationen. Ledaren behöver dessutom vara medveten om att även medarbetare i kunskapsintensiva verksamheter, som till synes är väldigt självständiga behöver ramar att förhålla sig till som är till för att fördela roller och ansvar.
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The Effects of Mycorrhizae and Soil Biota Feedback on the Outcome of Plant CompetitionStanescu, Sabina 05 September 2012 (has links)
The difference in the ability of plants to obtain resources has been used to predict the competition outcomes. Competitive interactions between plants can be influenced by trophic interactions. If mycorrhizae increase the growth of inferior competitors, then it can prevent competitive exclusion. I examined the effect of mycorrhizae on competitive interactions and found that inferior competitors had slow growth in the absence of mycorrhizae, but greater growth with mycorrhizae. By providing greater growth responses to inferior versus superior competitors, mycorrhizae promoted coexistence. In a separate experiment, I looked at the effects of whole soil biota on competitive ability. Coexistence can occur if dominant competitors experience negative feedback and or if inferior competitors experience positive feedback. I examined Plantago lanceolata L. specific feedback effects on competitive ability of 21 co-occurring species. I found that feedback effects did not affect hierarchies, and that positive feedback did not improve species competitive ability. / NSERC (Natural Science and Engineering Research Council), University of Guelph, Queen Elizabeth II Graduate Scholarship for Science and Technology
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Kvinnans rättigheter i rätten : Om våldtäktsdefinitionen i svensk sexualbrottslagstiftningwikblom, Ida January 2015 (has links)
During the past 10 years Sweden has updated its penal code for sexual crimes twice. Despite this few are convicted for the crime of rape in Sweden. As the majority of perpetrators being male, this is a problem concerning women’s rights to respect for their bodies and personal integrity. A possible explanation, and this study’s point of departure is a potential discrepancy between the intention of the law and the interpretation of the same as the Swedish legal system rests on a foundation of legal positivism. Hence focus of this study has been the motives behind the definition of rape in the law and the interpretation of the same. The purpose has been to establish the development of the rape law and its political motives, how the judicial system has interpreted the legal text in actual cases and if this is in alignment. As to explain why so few are convicted for the crime of rape and to critically examine how this affects women’s rights as well as how the interpretation of the definition of rape can be carried out in a more legally secure way for the victims. This has been done firstly by examining the states public investigations and state bills before the update of the penal codes definition of rape in 2005 and 2013. Secondly by an analysis of arguments used by the Swedish courts, mainly the district courts, in two rape convictions and three verdicts of acquittal. Arguments used by the courts have then been compared to the motives behind the legal definition of rape to see if the perceived discrepancy between the intended meaning of the law and the interpretation of the same existed. Thirdly, the judicial systems legal basis for interpretation was criticised from the two theoretical perspectives of the study; a criticism to legal positivism and a gender hierarchical perspective. The analysis shows that the updates of the rape law are clearly morally motivated and women’s rights based. In contrast to the legal positivistic judicial system interpretations, avoiding morally based argumentation relying on the systems foundation solely. The critical investigation shows that both a the perceived gender neutral system as well as legal positivistic tradition of sidestepping moral argumentation in courts result in lack of questioning the system and how it comes to its decisions. Hence the discrepancy between the two systems can be a part of the explanation why women’s rights are not secured in Sweden.
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Filtering of Segmentation Hierarchies for Improved Region-to-Region MatchingWalzer, Oliver 26 October 2011 (has links)
The representation and manipulation of visual content in a computer vision system requires a suitable abstraction of raw visual content such as pixels in an image. In this thesis, we study region-based feature representations and in particular, hierarchical segmentations because they do make no assumptions about region granularity. Hierarchical segmentations create a large feature space that increases the cost of subsequent processing in computer vision systems.
We introduce a segment filter to reduce the feature space of hierarchical segmentations by identifying unique regions in the images. The filter uses appearance-based properties of the regions and the structure of the segmentation for the selection of a small set of descriptive regions. The filter works in two phases: selection with a criteria based on relative region size and a sorting based on a variational criteria. The filter is applicable to any hierarchical segmentation algorithm, in particular to bottom-up and region growing approaches. We evaluate the filter's performance against an extensive set of ground-truth regions from a dataset containing image sequences with scenes of different complexity.
We demonstrate a novel region-to-region image matching approach as a possible application of our segment filter. A reduced segmentation tree is reconstructed based on the set of regions provided by the filtering. The reduction of the feature space by the segment filter simplifies our region-to-region matching approach. The correspondences between regions from two different images is established by a similarity measure. We use a modified mutual information measurement to compute the similarity of regions. The identified region correspondences are refined using the reduced segmentation tree. Our region-to-region matching approach is evaluated with an extensive set of ground-truth correspondences. This evaluation shows the large potential of both, our filtering and our matching approach.
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Multiple Versions and Overlap in Digital TextDesmond Schmidt Unknown Date (has links)
This thesis is unusual in that it tries to solve a problem that exists between two widely separated disciplines: the humanities (and to some extent also linguistics) on the one hand and information science on the other. Chapter 1 explains why it is essential to strike a balance between study of the solution and problem domains. Chapter 2 surveys the various models of cultural heritage text, starting in the remote past, through the coming of the digital era to the present. It establishes why current models are outdated and need to be revised, and also what significance such a revision would have. Chapter 3 examines the history of markup in an attempt to trace how inadequacies of representation arose. It then examines two major problems in cultural heritage and lin- guistics digital texts: overlapping hierarchies and textual variation. It assesses previously proposed solutions to both problems and explains why they are all inadequate. It argues that overlapping hierarchies is a subset of the textual variation problem, and also why markup cannot be the solution to either problem. Chapter 4 develops a new data model for representing cultural heritage and linguistics texts, called a ‘variant graph’, which separates the natural overlapping structures from the content. It develops a simplified list-form of the graph that scales well as the number of versions increases. It also describes the main operations that need to be performed on the graph and explores their algorithmic complexities. Chapter 5 draws on research in bioinformatics and text processing to develop a greedy algorithm that aligns n versions with non-overlapping block transpositions in O(M N ) time in the worst case, where M is the size of the graph and N is the length of the new version being added or updated. It shows how this algorithm can be applied to texts in corpus linguistics and the humanities, and tests an implementation of the algorithm on a variety of real-world texts.
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Insights from the use of a standard taxonomy for remote sensing analysisKari, Swapna. January 2004 (has links)
Thesis (M. S.) -- Mississippi State University. Department of Electrical and Computer Engineering. / Title from title screen. Includes bibliographical references.
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Applications of wireless communication in traffic networks using a hierarchical hybrid system modelLiu, Yiting, January 2007 (has links)
Thesis (Ph. D.)--Ohio State University, 2007. / Title from first page of PDF file. Includes bibliographical references (p. 171-182).
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