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The eastern Nearctic fauna of Blepharicera Macquart (Diptera: Blephariceridae) is revised to include twenty-three species, six of which are new to science. Descriptions of the larvae, pupae, and adults of B. amnicula n. sp., B. conifera n. sp., B. crista n. sp., B. enoristera n. sp., B. hillabee n. sp., and B. opistera n. sp. are presented. Keys to instar IV larvae, pupae, and adults of all eastern Blepharicera (except B. caudata Courtney) are provided. Phylogenetic studies were conducted to determine the relationships between eastern and western Nearctic Blepharicera and among species within these groups. Larvae, pupae, and adults were available for all known Nearctic species except B. caudata and B. micheneri Alexander. Molecular data acquired from two genes and morphological data for 44 characters were used to test previous phylogenetic hypotheses on the historical relationships and biogeography of Nearctic Blepharicera. Analyses using maximum parsimony, maximum likelihood, and Bayesian inference were conducted. Resulting phylogenies support monophyly of the B. tenuipes and B. micheneri groups and suggest that multiple species complexes may exist within the B. tenuipes group.

Farmers are always looking for ways to increase yields and profits and no-tillage may be a way to achieve this goal. However, a comprehensive study of the performance of no-tillage yields relative to conventional tillage yields and their net returns is lacking. This study evaluated the potential factors that influence differences in conventional tillage and no-tillage yields and net returns as explained by such factors as time, crop, precipitation, soil texture and geographic region. Data were collected from 442 paired tillage experiments growing corn, soybeans, cotton, oats, wheat and sorghum published in three refereed journals. Data were evaluated using a mixed model and logit model respectively, to evaluate differences in mean yields and downside risk with no-tillage compared to tillage. Sorghum and wheat were found to have higher no-tillage yields relative to tillage. No-tillage was also found to outperform conventional tillage in the southern United States with just the opposite occurring in the northern U.S. A silty soil was also found to reduce no-tillage yields. Several factors were found to decrease the chance of downside risk with no-tillage, they were sorghum, sandy soil, Northern Crescent, Northern Great Plains, Prairie Gateway and Southern Seaboard regions. Two factors that increased the chance of lowered no-tillage yields were increased rainfall and length of use of no-tillage. Differences in mean net returns and downside risk were evaluated using a mixed model and logit model. Results showed that no-tillage was more profitable than conventional tillage in the Mississippi Portal region, but less profitable in the Prairie Gateway. Net returns were lower for no-tillage wheat and soybeans when produced in a clay soil. Cotton grown in sand had higher no-till net returns, but increased rainfall decreased cotton net returns. A logit model showed certain factors decreased the probability of lower no-tillage net returns. There was less downside risk with wheat grown under no-tillage as well as less downside risk in the Southern Seaboard region and when no-tillage was used on a clay soil. There were factors that increased the probability of lower no-tillage net returns; increased precipitation, Northern Great Plains, Prairie Gateway and Basin & Range regions.

La mise en forme de l'alliage d'aluminium de corroyage 7075 de pièces fonctionnelles à géométrie complexe se fait la plupart du temps par usinage. Pour un nombre de pièces important, le coût peut être réduit en réalisant une ébauche par forgeage. Il est cependant plus intéressant de réaliser une ébauche proche des dimensions finales pour limiter l'usinage (aspect near-net-shape). Pour mettre en forme une pièce à géométrie complexe en une seule étape, la résistance à la déformation de la matière doit être suffisamment faible. Cette faible déformation nécessite la génération d'une phase liquide, ce qui introduit des défauts dans l'alliage de corroyage tels que la fissuration à chaud, porosité, retassure, retrait important, macroségrégation solide-liquide. L'apparition de ces défauts peut être réduite en limitant la fraction volumique de la phase liquide à 0.1. AA 7075 étant particulièrement sensible à la fissuration à chaud, un faible retrait est un atout. Nous choisirons le procédé RAP pour obtenir une matière globulaire semi-solide. Ce procédé utilise la recristallisation d'une matière extrudée pour réaliser une matière qui a un comportement rhéofluidifiant-thixotrope. Le procédé de mise en forme de cette matière semi-solide globulaire à faible phase liquide est le thixoforgeage. Des essais de chauffage de la matière extrudée et de filage permettront d'étudier l'influence des divers paramètres du procédé sur l'effort de mise en forme et sur la qualité des pièces produites. Nous adapterons les paramètres de chauffage et de mise en forme sur un outillage spécialement conçu pour le thixoforgeage pour des pièces à géométrie simple et pour des pièces à géométrie complexe. Une étude de l'influence des paramètres sur les caractéristiques mécaniques et sur la qualité des pièces a montré le très bon potentiel de mise en forme de AA 7075 par thixoforgeage.

It is a research of the move trajectory of the ciliates while feeding the food, in order to estimate, differentiate from the movement behavior under different environments. First, discuss the differently distinguish with the single indicator. Second, discuss with integrate four kinds of indicator whether can distinguish differently. Finally, combine the indicator data and through different analysis technology look out the features of movement behavior, expect to be able to look out suitable information and knowledge from the indicator data. After deal with analytical technology, the result of decision tree is most suitable for predicted and have credibilities. If according to energy of biological, the analysis result is similar to optimal foraging theory. And learn from result under different condition, the movement behavior of the ciliates similar to the optimal foraging theory. In the matter of the result of analysis technology, data of the density of low food similar to data of the density of extremely high food. Besides, data of medium food and high food are analogous. The rule of decision tree can distinguish the density of different food, and can offer follow-up study to distinguish the environmental conditions. Those models are evaluated by predicting accuracies, and rules extracted from decision tree models are also of great help to prediction as well.

Vår undersökning utgick från de vetenskapliga frågeställningarna ” Vad styr utrikeskorrespondenternas utformning av nyhetsnätet?” och ”Vilka konsekvenser har relationen till hemmaredaktionen för arbetsrutinerna och nyhetsnätet?” Vi stödjer oss på Gaye Tuchmans teori om news net, nyhetsnätet. Teorin går i korta ordalag ut på att man som journalist behöver en systematiserad nyhetsinsamling, ett nyhetsnät, för att på bästa sätt bedriva journalistiskt arbete. Varför är detta intressant? Bakgrunden till vår uppsats är att vi tror att utrikeskorrespondenter har ett för reportrar annorlunda arbetssätt till följd av deras förutsättningar (verksamma i ett annat land, samhälle etc.) Frågeställningen kring relationen till hemmaredaktionen är relevant eftersom utrikeskorrespondenten får antas ha ett kunskapsövertag gentemot hemmaredaktionen vad gäller det geografiska området korrespondenten är satt att bevaka. Vi har utfört kvalitativa forskningsintervjuer med ett urval av utrikeskorrespondenter som alla representerar europeisk tryckt press, och som alla är baserade i Stockholm. Resultatet av studien visar att rikstäckande tryckt press styr utformningen av utrikeskorrespondenternas nyhetsnät när de letar efter uppslag till artiklar. Ytterligare en central fråga var hur deras värdering av offentliga källor och kontakter kontra personliga såg ut. Den slutsats vi dragit är att det i stor utsträckning är den specifika uppdragsgivarens läsekrets och resurser som styr hur korrespondenterna värderar offentliga respektive personliga källor. Relationen till hemmaredaktionen visade sig bygga på en relativ balans där korrespondenten sågs som expertis på området och regionen. Detta gör i sin tur att det i första hand är korrespondenten som hör av sig till redaktionen, i och med att hen har ”exklusiv” kunskap om vad det är som är värt att skriva om.

The survivability concerns the service continuity when the components of a system are damaged. This concept is especially useful in the emergency management of the system, as often emergencies involve accidents or incident disasters which more or less damage the system. The overall objective of this thesis study is to develop a quantitative management approach to the emergency management of a wireless cellular telecommunication system in light of its service continuity in emergency situations namely the survivability of the system. A particular wireless cellular telecommunication system, WCDMA, is taken as an example to ground this research.<p>The thesis proposes an ontology-based paradigm for service management such that the management system contains three models: (1) the work domain model, (2) the dynamic model, and (3) the reconfiguration model. A powerful work domain modeling tool called Function-Behavior-Structure (FBS) is employed for developing the work domain model of the WCDMA system. Petri-Net theory, as well as its formalization, is applied to develop the dynamic model of the WCDMA system. A concept in engineering design called the general and specific function concept is applied to develop a new approach to system reconfiguration for the high survivability of the system. These models are implemented along with a user-interface which can be used by emergency management personnel. A demonstration of the effectiveness of this study approach is included.<p>There are a couple of contributions with this thesis study. First, the proposed approach can be added to contemporary telecommunication management systems. Second, the Petri Net model of the WCDMA system is more comprehensive than any dynamic model of the telecommunication systems in literature. Furthermore, this model can be extended to any other telecommunication system. Third, the proposed system reconfiguration approach, based on the general and specific function concept, offers a unique way for the survivability of any service provider system.<p>In conclusion, the ontology-based paradigm for a service system management provides a total solution to service continuity as well as its emergency management. This paradigm makes the complex mathematical modeling of the system transparent to the manager or managerial personnel and provides a feasible scenario of the human-in-the-loop management.

The purpose of this qualitative study is to advance an understanding of trust and perceived intrusiveness in online advertising. The theoretical framework in this thesis is based upon theories about trust and intrusiveness that derives from previous research. The theory of psychological reactance is a further constituent. These concepts and theories are defined and discussed. and possible models are introduced. Semi-structured interviews with eight individuals of the Net Generation have been conducted to gather empirical data. The recordings from these interviews have thereafter been transcribed. in order to analyse the collected data, we have adopted a thematic analysis consisting of six phases. We coded the data and created themes that were detected during the different phases. The empirical data has been gathered by conduction of eight semi-structured interviews with individuals of the Net Generation. These interview have thereafter been transcribed and its content coded as a first step of the analysis. Three global themes derived from the empirical data analysis; trust, intrusiveness and observed relations, and many basic themes defined and analysed and discussed. We conclude our study advancing our findings about an understanding of trust and perceived intrusiveness in online advertising, as well as some observed relations noticed during the analysis. We finish our thesis with some managerial implications about the importance for managers and advertisers to take into account trust and intrusiveness, as well as leads for further studies, including the testing of our developed research model through a quantitative strategy.

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No description available.